{ "questions": [ { "idx": 172, "question": "Adding 50mol% Na2O to SiO2, can this ratio form a glass? Why?", "answer": "Yes, it can form a glass. When 50mol% Na2O is added, although the continuous SiO network skeleton becomes relaxed, it still maintains a three-dimensional network structure, allowing the formation of a glass.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么50mol% Na2O添加到SiO2中可以形成玻璃，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要理解Na2O和SiO2在玻璃形成中的作用，并分析特定比例下网络结构的变化，涉及多步概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解玻璃形成的条件以及Na2O对SiO2网络结构的影响，并进行综合分析。虽然题目涉及多步计算和概念关联，但在选择题型中，正确选项已经提供了关键分析步骤和结论，降低了答题的复杂程度。", "convertible": true, "correct_option": "Yes, it can form a glass. When 50mol% Na2O is added, although the continuous SiO network skeleton becomes relaxed, it still maintains a three-dimensional network structure, allowing the formation of a glass.", "choice_question": "Adding 50mol% Na2O to SiO2, can this ratio form a glass?", "conversion_reason": "The answer is a clear and concise explanation that can be directly used as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice structure by focusing on the key query about glass formation.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because the 3D SiO network remains intact despite network modifiers", "B": "No, because exceeding 30mol% modifier oxides always disrupts glass formation", "C": "Only if rapidly quenched, otherwise it will crystallize", "D": "Yes, but only if Al2O3 is also present to stabilize the structure" }, "correct_answer": "A", "explanation": { "correct": "A is correct because at 50mol% Na2O, while the network is significantly modified, the SiO4 tetrahedra still maintain sufficient connectivity to form a glassy structure. The key is the persistence of the 3D network framework.", "distractors": { "B": "This exploits the common misconception about rigid cutoff values in glass formation. While 50mol% is high, it's not an absolute limit for silicate glasses.", "C": "This creates a false requirement for rapid quenching. While cooling rate affects glass formation, it's not decisive at this composition.", "D": "This introduces an unnecessary additional component. While Al2O3 can enhance glass formation, it's not required for this binary system." } }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2162, "question": "When a compressive force is applied along the [0001] direction of a hexagonal close-packed single crystal, what are the possibilities of deformation and the primary mode of deformation?", "answer": "The slip plane of hexagonal close-packed metals is (0001), and the resolved shear stress on the slip plane in the [0001] direction is zero, so the single crystal cannot slip. During compression, after elastic deformation, twinning may occur.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释在特定条件下材料的变形可能性及主要变形模式，答案提供了详细的文字解释和论述，没有涉及选择题、判断题或计算题的特征。 | 知识层次: 题目要求分析六方密堆积单晶在特定方向受压时的变形可能性及主要变形模式，涉及对滑移面和孪生变形的理解，需要将晶体结构、滑移系和应力分析等概念关联起来进行综合分析。虽然不涉及复杂计算，但需要多步推理和概念关联，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，需要考生具备以下能力：", "convertible": true, "correct_option": "Twinning may occur after elastic deformation.", "choice_question": "When a compressive force is applied along the [0001] direction of a hexagonal close-packed single crystal, what is the primary mode of deformation?", "conversion_reason": "The answer is a standard concept in materials science, making it suitable for conversion to a multiple-choice format. The primary mode of deformation can be clearly identified as twinning after elastic deformation.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Basal slip on (0001) plane", "B": "Prismatic slip on {10-10} planes", "C": "Pyramidal slip on {11-22} planes", "D": "Twinning after elastic deformation" }, "correct_answer": "D", "explanation": "The correct answer is D because compression along the [0001] direction in HCP crystals initially causes elastic deformation followed by twinning, as this direction has no easy slip systems. Option A is a cognitive bias trap - basal slip is the easiest slip system but cannot operate under [0001] compression. Option B exploits professional intuition by suggesting prismatic slip which is common but requires shear stress components absent in pure [0001] compression. Option C is a multi-level verification trap - pyramidal slip is possible but requires much higher stresses than twinning under these conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1888, "question": "Crystals have basic properties such as (1) (2) (3) and (4).", "answer": "1) Symmetry; (2) Crystallographic homogeneity; (3) Anisotropy; (4) Self-confinement (or minimal internal energy property)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写晶体的基本性质，需要文字解释和列举具体性质，而不是从选项中选择或判断对错，也不涉及计算。 | 知识层次: 题目考查晶体基本性质的记忆，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需回忆晶体的基本性质即可完成作答。题目直接列出了四个基本性质，没有涉及概念解释或复杂概念体系的阐述，解题步骤简单，对知识点的掌握深度要求较低。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Symmetry; Crystallographic homogeneity; Anisotropy; Self-confinement (or minimal internal energy property)", "choice_question": "Crystals have basic properties such as:", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。题目可以改写为适合选择的形式，答案可以作为正确选项。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Symmetry; Crystallographic homogeneity; Anisotropy; Self-confinement", "B": "Symmetry; Isotropy; Long-range order; Minimal surface energy", "C": "Symmetry; Crystallographic homogeneity; Elastic modulus; Self-confinement", "D": "Symmetry; Crystallographic defects; Anisotropy; Self-confinement" }, "correct_answer": "A", "explanation": "正确答案A包含了晶体的四个基本特性：对称性、结晶学均匀性、各向异性和自限性（或最小内能特性）。干扰项B用各向同性替代了各向异性，这是晶体不常见的特性；用长程有序替代了结晶学均匀性，虽然相关但不完全准确；用最小表面能替代了自限性，这是表面特性而非晶体基本特性。干扰项C用弹性模量替代了各向异性，弹性模量是材料力学性能而非晶体基本特性。干扰项D用结晶缺陷替代了结晶学均匀性，缺陷是晶体中的不完美而非基本特性。这些干扰项利用了材料科学中常见概念的混淆和直觉判断的陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4150, "question": "In the visible spectrum, an electrical insulator that is a single crystal and without porosity is normally(a) Transparent(b) Opaque(c) Translucent", "answer": "In the visible spectrum, an electrical insulator that is a single crystal and without porosity\nnormally transparent.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项（Transparent, Opaque, Translucent）中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查对材料光学性质的基本概念记忆和理解，特别是关于单晶无孔绝缘体在可见光谱中的透明性这一基础知识点。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别单晶无孔绝缘体在可见光谱下的透明特性。选项直接对应材料科学基本概念，无需复杂分析或概念辨析，属于最简单的难度等级。", "convertible": true, "correct_option": "Transparent", "choice_question": "In the visible spectrum, an electrical insulator that is a single crystal and without porosity is normally:", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer, making it directly convertible to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dislocation density decreases exponentially with annealing temperature", "B": "The yield strength increases linearly with grain size according to Hall-Petch relationship", "C": "The electrical conductivity of pure metals is primarily limited by phonon scattering at room temperature", "D": "The fracture toughness of ceramics is inversely proportional to the square root of grain size" }, "correct_answer": "C", "explanation": "Correct answer is C because in pure metals at room temperature, electron-phonon scattering is indeed the dominant mechanism limiting conductivity. Option A is a cognitive bias trap - while dislocation density generally decreases with annealing, the relationship is not exponential. Option B reverses the Hall-Petch relationship, exploiting a common memorization error. Option D creates a false analogy to the Hall-Petch relationship for strength, while in reality fracture toughness in ceramics shows complex grain size dependence.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4181, "question": "Give the electron configuration for the ion Ba2+.", "answer": "The electron configuration for a Ba2+ ion is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出Ba2+离子的电子排布，答案是一个详细的电子排布序列，需要文字描述而非选择、判断或计算。 | 知识层次: 题目考查对电子排布的基本概念的记忆和理解，不需要复杂的计算或分析，只需记住Ba2+离子的电子排布即可。 | 难度: 在选择题型中，该题目仅要求记忆基础概念（电子排布式），无需解释或分析。正确选项直接给出了完整的电子排布式，属于最基础的定义简答类型。", "convertible": true, "correct_option": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6", "choice_question": "What is the electron configuration for the ion Ba2+?", "conversion_reason": "The answer is a standard and specific electron configuration, which can be presented as a correct option among other plausible but incorrect configurations.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6", "B": "[Xe] 6s2", "C": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 6s2", "D": "[Xe] 4f14 5d10 6s2" }, "correct_answer": "A", "explanation": "The correct answer is A because Ba2+ loses two electrons from the neutral Ba atom's configuration, which removes the 6s2 electrons. Option B is the ground state configuration of neutral Ba, not the ion. Option C includes the 6s2 electrons that should be removed. Option D represents the configuration of Hg, not Ba2+, exploiting the tendency to confuse isoelectronic species in the same period.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 782, "question": "2. First-order phase transition", "answer": "First-order phase transition: During the phase transition, the chemical potentials of the two phases are equal, but the first-order partial derivatives of the chemical potential are not equal. A first-order phase transition involves latent heat and volume changes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"First-order phase transition\"进行文字解释和论述，答案提供了详细的定义和特征描述，符合简答题的特点。 | 知识层次: 题目考查对一级相变的基本定义和特征的理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生理解并描述一级相变的基本特征，包括化学势的相等和其一阶偏导数的不相等，以及涉及潜热和体积变化。这需要考生不仅记住定义，还需要对概念进行一定的解释和描述，但不需要进行复杂的体系阐述或比较分析。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "First-order phase transition: During the phase transition, the chemical potentials of the two phases are equal, but the first-order partial derivatives of the chemical potential are not equal. A first-order phase transition involves latent heat and volume changes.", "choice_question": "Which of the following correctly describes a first-order phase transition?", "conversion_reason": "The answer is a standard definition or description of a first-order phase transition, which can be presented as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "First-order phase transition: During the phase transition, the chemical potentials of the two phases are equal, but the first-order partial derivatives of the chemical potential are not equal. A first-order phase transition involves latent heat and volume changes.", "B": "First-order phase transition: The Gibbs free energy is continuous but its first derivative with respect to temperature is discontinuous. This transition is characterized by a change in symmetry without latent heat.", "C": "First-order phase transition: Both the chemical potential and its first derivative with respect to pressure are continuous. The transition occurs without any volume change or latent heat absorption.", "D": "First-order phase transition: The entropy and volume remain continuous during the transition, but the heat capacity shows a discontinuity. This is typical of magnetic phase transitions." }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately describes the defining characteristics of a first-order phase transition: equality of chemical potentials but discontinuity in their first derivatives, accompanied by latent heat and volume changes. Option B incorrectly describes a second-order transition (continuous Gibbs energy with discontinuous first derivative). Option C is completely wrong as it contradicts the very definition of first-order transitions. Option D describes behavior typical of higher-order transitions, not first-order. The distractors exploit common confusions between different orders of phase transitions and misattribute properties from other transition types.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2983, "question": "Calculate the diffusion coefficient D of carbon at 920°C, given the activation energy for diffusion is 133984 J/mol and D0=0.23 cm²/s.", "answer": "D = D0 × exp(-Q/(RT)) = 0.23 × exp(-133984/(8.314 × (273 + 920))) = 3.12 × 10^-7 cm²/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出扩散系数D的具体数值。答案是一个具体的计算结果，而不是选择、判断或文字解释。 | 知识层次: 题目主要考查基本公式的直接应用和简单计算，涉及扩散系数的计算，需要套用给定的公式和参数进行数值计算，思维过程较为直接，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用一个基本公式（D = D0 × exp(-Q/(RT))）并进行简单的数值计算。题目没有涉及多个公式的组合或复杂的逻辑推理，属于单一公式直接计算的类型，因此在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "3.12 × 10^-7 cm²/s", "choice_question": "Calculate the diffusion coefficient D of carbon at 920°C, given the activation energy for diffusion is 133984 J/mol and D0=0.23 cm²/s. The correct value of D is:", "conversion_reason": "The calculation has a definite numerical answer, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.12 × 10^-7 cm²/s", "B": "1.56 × 10^-6 cm²/s", "C": "6.24 × 10^-7 cm²/s", "D": "2.34 × 10^-7 cm²/s" }, "correct_answer": "A", "explanation": "正确答案A是通过阿伦尼乌斯方程D=D0*exp(-Qd/RT)精确计算得出，其中温度需转换为开尔文(1193K)，R=8.314 J/(mol·K)。干扰项B是常见错误，源于忘记温度单位转换(直接使用920而非1193K)。干扰项C是正确答案的两倍，针对可能忽略指数运算顺序的AI。干扰项D利用视觉相似性设计，数值接近但错误，针对快速扫描的AI模型。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3743, "question": "A 2-in.-diameter copper rod is reduced to 1.5 in. diameter, then reduced again to a final diameter of 1 in. In a second case, the 2-in.-diameter rod is reduced in one step from 2 in. to a 1 in. diameter. Calculate the% CW for both cases.", "answer": "75% in both cases.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解两种不同加工路径下的% CW（冷加工百分比），答案以具体数值形式给出，属于典型的计算题。 | 知识层次: 题目要求应用冷加工百分比计算公式进行简单计算，虽然涉及多步操作但计算过程直接套用公式即可完成，无需复杂分析或概念关联。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然题目描述了两种不同的加工步骤，但实际计算只需要套用冷加工百分比（%CW）的基本公式，且两种情况的计算过程相同，最终结果也一致。不需要复杂的分析或多步骤推导，属于直接套用公式的简单应用层次。", "convertible": true, "correct_option": "75% in both cases", "choice_question": "A 2-in.-diameter copper rod is reduced to 1.5 in. diameter, then reduced again to a final diameter of 1 in. In a second case, the 2-in.-diameter rod is reduced in one step from 2 in. to a 1 in. diameter. The % CW for both cases is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "75% in both cases", "B": "56.25% for two-step, 75% for single-step", "C": "43.75% for two-step, 75% for single-step", "D": "56.25% in both cases" }, "correct_answer": "A", "explanation": "The correct answer is A because cold work percentage (%CW) depends only on the initial and final cross-sectional areas, not the intermediate steps. Both cases start at 2-in. diameter (3.14 in² area) and end at 1-in. diameter (0.79 in² area), giving 75% CW. Option B exploits the misconception that intermediate steps affect total CW by calculating 56.25% for the first reduction (2→1.5 in). Option C uses incorrect area calculations for the two-step process. Option D applies the wrong principle that %CW averages between steps.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2032, "question": "A polymeric material contains polyvinyl chloride, with 900 monomers in one molecule. If each molecule can be stretched into a linear molecule, calculate the theoretically maximum strain that can be achieved for this polymer (assuming the bond length of each C-C bond is $0.154\\\\mathrm{nm}$).", "answer": "The theoretically maximum strain is $3380\\\\%$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算最大应变），并给出了具体的输入参数（单体数量、键长）和输出结果（应变百分比）。解答过程需要应用公式和数学计算，符合计算题的特征。 | 知识层次: 题目需要进行多步计算（包括单体数量、键长计算和应变公式应用），并需要理解聚合物链的线性拉伸概念，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解聚合物分子链的拉伸概念、单体数量与总长度的关系，并进行多步计算（包括单位转换和百分比计算）。虽然题目提供了明确的参数和公式，但解题过程涉及多个步骤的综合分析，对学生的应用能力和计算准确性要求较高。", "convertible": true, "correct_option": "3380%", "choice_question": "A polymeric material contains polyvinyl chloride, with 900 monomers in one molecule. If each molecule can be stretched into a linear molecule, what is the theoretically maximum strain that can be achieved for this polymer (assuming the bond length of each C-C bond is $0.154\\mathrm{nm}$)?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3380%", "B": "450%", "C": "1800%", "D": "6750%" }, "correct_answer": "A", "explanation": "The correct answer is A (3380%) because for a polymer with 900 monomers, the maximum strain is calculated by considering the fully extended length (900 x 0.154 nm x 2 for C-C bonds) versus the coiled length. Option B (450%) is a common mistake from incorrectly assuming only single bond lengths without considering the polymer's full extension. Option C (1800%) is designed to trap those who miscalculate by forgetting to double the bond length for the extended conformation. Option D (6750%) exploits the tendency to overestimate by incorrectly squaring the monomer count.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 731, "question": "In a narrow sense, the phase transition process is a physical change process", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对相变过程基本概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆狭义相变过程的定义即可作答，无需深入理解或分析。", "convertible": true, "correct_option": "√", "choice_question": "In a narrow sense, the phase transition process is a physical change process", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All phase transitions in materials science involve a change in the chemical composition of the substance.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because phase transitions typically refer to changes in physical state (solid, liquid, gas) or crystal structure without altering chemical composition. Only chemical reactions change composition. The absolute term 'all' makes this particularly misleading as it excludes polymorphic transformations and other physical phase changes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 485, "question": "In the solid-state crystal diffusion process, the direction of diffusing atom migration is always from high concentration to low concentration.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查固体晶体扩散过程中原子迁移方向的基本概念，属于对基本原理的记忆和理解。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆扩散过程的基本原理即可作答，无需深入理解或分析多个概念，解题步骤简单直接。", "convertible": true, "correct_option": "√", "choice_question": "In the solid-state crystal diffusion process, the direction of diffusing atom migration is always from high concentration to low concentration.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In a binary alloy system exhibiting uphill diffusion, the direction of atomic migration is always opposite to the concentration gradient.", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "Uphill diffusion is a special case where atoms diffuse against the concentration gradient due to thermodynamic factors like chemical potential gradients. While this seems counterintuitive compared to normal Fickian diffusion, it's a well-documented phenomenon in certain alloy systems where 'always' correctly applies to this specific condition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4530, "question": "A continuous and aligned fiber-reinforced composite is to be produced consisting of 30 vol% aramid fibers and 70 vol% of a polycarbonate matrix; mechanical characteristics of these two materials are as follows: Modulus of Elasticity for Aramid fiber is 131 GPa (19x10^6 psi) and Tensile Strength is 3600 MPa (520,000 psi); Modulus of Elasticity for Polycarbonate is 2.4 GPa (3.5x10^5 psi) and Tensile Strength is 65 MPa (9425 psi). Also, the stress on the polycarbonate matrix when the aramid fibers fail is 45 MPa (6500 psi). For this composite, compute the longitudinal tensile strength.", "answer": "the longitudinal tensile strength is 1100 mpa (160,000 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的材料参数和体积分数，应用复合材料力学中的混合法则（Rule of Mixtures）进行数值计算，以确定复合材料的纵向拉伸强度。答案是一个具体的数值结果，这符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要综合运用复合材料力学性能的计算方法，包括体积分数、弹性模量和拉伸强度的复合效应计算。虽然不涉及复杂的机理解释或创新设计，但需要一定的综合分析能力来推导纵向拉伸强度。 | 难度: 在选择题中属于中等偏上难度，需要理解复合材料力学性能的基本概念，掌握纵向拉伸强度的计算方法，并进行多步计算。题目涉及纤维和基体的体积分数、弹性模量、拉伸强度等多个参数的综合运用，且需要正确应用混合法则进行计算。虽然题目提供了所有必要参数，但解题过程需要一定的综合分析能力。", "convertible": true, "correct_option": "1100 MPa (160,000 psi)", "choice_question": "A continuous and aligned fiber-reinforced composite is to be produced consisting of 30 vol% aramid fibers and 70 vol% of a polycarbonate matrix; mechanical characteristics of these two materials are as follows: Modulus of Elasticity for Aramid fiber is 131 GPa (19x10^6 psi) and Tensile Strength is 3600 MPa (520,000 psi); Modulus of Elasticity for Polycarbonate is 2.4 GPa (3.5x10^5 psi) and Tensile Strength is 65 MPa (9425 psi). Also, the stress on the polycarbonate matrix when the aramid fibers fail is 45 MPa (6500 psi). For this composite, what is the longitudinal tensile strength?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1100 MPa (160,000 psi)", "B": "1085 MPa (157,000 psi)", "C": "3600 MPa (520,000 psi)", "D": "45 MPa (6500 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the rule of mixtures for fiber-reinforced composites when fibers fail first. Option B is a close numerical trap that incorrectly accounts for matrix stress contribution. Option C is the fiber strength alone, a common oversight when forgetting matrix contribution. Option D is the matrix stress at fiber failure, misleadingly suggesting pure matrix behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 962, "question": "Briefly describe the slip system", "answer": "A slip system in a crystal refers to a combination of a slip plane and a slip direction on that plane.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述滑移系统的定义，答案以文字解释的形式给出，符合简答题的特征 | 知识层次: 题目考查对滑移系统这一基本概念的定义记忆和理解，属于材料科学中的基础知识点，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"滑移系统\"的基本定义，属于最基础的概念记忆层次。题目仅涉及单一概念的定义复述，无需解释或比较多个概念，解题步骤极为简单，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "A slip system in a crystal refers to a combination of a slip plane and a slip direction on that plane.", "choice_question": "Which of the following best describes a slip system in a crystal?", "conversion_reason": "The answer is a standard definition of a slip system, which can be presented as a correct option among other plausible but incorrect definitions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A combination of a slip plane and a slip direction on that plane", "B": "The system governing elastic deformation through atomic bond stretching", "C": "The primary mechanism for twinning deformation in BCC crystals", "D": "A mathematical model predicting dislocation nucleation sites" }, "correct_answer": "A", "explanation": "The correct answer is A because a slip system is fundamentally defined by the crystallographic plane (slip plane) and direction (slip direction) along which dislocation motion occurs. Option B is incorrect as it describes elastic deformation rather than plastic deformation via slip. Option C is a cognitive bias trap - while twinning is important in BCC crystals, it's distinct from slip systems. Option D is a professional intuition trap that sounds plausible but describes dislocation nucleation theory rather than slip systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1247, "question": "What is the movement of an edge dislocation perpendicular to the slip plane called?", "answer": "Climb", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用一个特定的术语（\"Climb\"）来回答问题，而不是从多个选项中选择或判断对错，也不需要计算或公式应用。这符合简答题的特征，即需要简洁准确的回答。 | 知识层次: 题目考查对位错运动基本概念的记忆和理解，特别是边缘位错在垂直于滑移面方向上的运动名称。这属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即边缘位错垂直于滑移面运动的名称。正确选项\"Climb\"是材料科学中的基本术语，属于直接的定义性知识，无需复杂推理或概念关联。选择题型中此类直接考查定义的题目属于最低难度等级。", "convertible": true, "correct_option": "Climb", "choice_question": "What is the movement of an edge dislocation perpendicular to the slip plane called?", "conversion_reason": "The answer is a standard term in the field of materials science, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Climb", "B": "Glide", "C": "Cross-slip", "D": "Twist" }, "correct_answer": "A", "explanation": "The correct answer is A (Climb) because edge dislocation movement perpendicular to the slip plane requires diffusion of atoms/vacancies, which defines climb. B (Glide) is incorrect as it describes dislocation movement within the slip plane. C (Cross-slip) is incorrect as it refers to screw dislocations changing slip planes. D (Twist) is incorrect as it describes a type of grain boundary, not dislocation motion. The interference strategies: 1) Glide exploits the common confusion between parallel/perpendicular motion, 2) Cross-slip targets those who confuse edge/screw dislocation behavior, 3) Twist preys on the tendency to associate 'perpendicular' with rotational terms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 248, "question": "Given the diffusion data of hydrogen in face-centered cubic iron as D_Ni = 0.0063 exp(-10300 × 4.18 / RT) cm²/s, calculate the diffusion coefficient at 1000°C.", "answer": "Substituting T=1000°C into the equation yields D_H=3.6×10^-5 cm²/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的扩散公式和温度条件进行数值计算，最终得出扩散系数的具体数值。答案是一个具体的计算结果，而不是选择、判断或文字解释。 | 知识层次: 题目要求直接套用给定的扩散系数公式进行数值计算，仅需简单的代数运算和单位转换，不涉及多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目仅需要直接套用给定的扩散系数公式，并进行简单的温度单位转换和数值计算。解题步骤非常直接，不涉及多个公式的组合或复杂的概念分析，因此属于单一公式直接计算的难度等级1。", "convertible": true, "correct_option": "3.6×10^-5 cm²/s", "choice_question": "Given the diffusion data of hydrogen in face-centered cubic iron as D_Ni = 0.0063 exp(-10300 × 4.18 / RT) cm²/s, what is the diffusion coefficient at 1000°C?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.6×10^-5 cm²/s", "B": "1.2×10^-4 cm²/s", "C": "6.3×10^-3 cm²/s", "D": "2.1×10^-6 cm²/s" }, "correct_answer": "A", "explanation": "The correct answer is A (3.6×10^-5 cm²/s) calculated using the Arrhenius equation at 1000°C (1273K). Option B (1.2×10^-4 cm²/s) is a common error from misapplying the pre-exponential factor. Option C (6.3×10^-3 cm²/s) represents the pre-exponential factor itself, a trap for those who forget the exponential term. Option D (2.1×10^-6 cm²/s) comes from incorrect unit conversion of the activation energy. Each incorrect option exploits different cognitive biases in diffusion coefficient calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 413, "question": "1. In the ionic crystal structure, the positive and negative ions form (1)", "answer": "coordination polyhedron", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（coordination polyhedron）作为答案，而不是从多个选项中选择或判断对错，也不需要计算。这符合简答题的特征，即需要提供简短而具体的答案。 | 知识层次: 题目考查的是对离子晶体结构中正负离子排列方式的基本概念记忆，即配位多面体的定义，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需要考生回忆并识别\"coordination polyhedron\"这一专业术语的定义。题目直接考查对离子晶体结构中正负离子排列方式的基本概念，不需要进行任何解释或分析，属于最简单的记忆性知识考查。", "convertible": true, "correct_option": "coordination polyhedron", "choice_question": "In the ionic crystal structure, the positive and negative ions form:", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "coordination polyhedron", "B": "Bravais lattice", "C": "unit cell", "D": "crystallographic plane" }, "correct_answer": "A", "explanation": { "correct_answer": "In ionic crystals, the arrangement of oppositely charged ions around a central ion forms a coordination polyhedron, which describes the geometric configuration of nearest neighbors.", "distractors": { "B": "Bravais lattice is a tempting choice as it describes the overall 3D periodic arrangement, but it doesn't specifically capture the local ion coordination geometry.", "C": "Unit cell is incorrect because while it represents the repeating structural unit, it doesn't describe the specific arrangement of ions around each other.", "D": "Crystallographic plane is misleading as it refers to 2D atomic arrangements rather than the 3D coordination environment." }, "trap_strategies": { "B": "Exploits the common confusion between overall crystal structure and local coordination environment", "C": "Capitalizes on the tendency to confuse structural repeating units with local atomic arrangements", "D": "Leverages the similarity in terminology between 2D and 3D structural descriptors" } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4172, "question": "Relative to electrons and electron states, what does the n quantum number specify?", "answer": "The n quantum number designates the electron shell.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释n量子数的含义，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对量子数n的基本定义和作用的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对n量子数定义的基本记忆，属于最基础的概念性知识。正确选项直接给出了定义，无需任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The n quantum number designates the electron shell.", "choice_question": "Relative to electrons and electron states, what does the n quantum number specify?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The principal energy level of the electron", "B": "The orbital angular momentum of the electron", "C": "The magnetic moment orientation of the electron", "D": "The spin state of the electron" }, "correct_answer": "A", "explanation": "The n quantum number (principal quantum number) specifically designates the principal energy level or shell of an electron. Option B is incorrect because orbital angular momentum is specified by the l quantum number. Option C is incorrect as magnetic moment orientation is determined by the m_l quantum number. Option D is incorrect since electron spin is described by the m_s quantum number. These distractors exploit common confusion between the four quantum numbers and their respective physical meanings.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2305, "question": "Explain why in short-fiber composites with $L Burgers vector; 3) b3 = (a/3)[1̄1̄1̄] is a Frank partial dislocation with a/3<111> Burgers vector. Option B reverses the types of b1 and b2, exploiting confusion between full and partial dislocations. Option C incorrectly assigns the Frank partial to b2 and Shockley to b3, targeting misclassification of partial dislocation types. Option D creates a blanket statement that all are partial dislocations, preying on the tendency to overgeneralize when faced with multiple Burgers vector magnitudes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2118, "question": "Point out the errors in the following concepts and correct them: When observing the microstructure of eutectoid steel, it is found that the figure shows different densities of cementite lamellae. Areas with dense lamellae have higher carbon content, while areas with sparse lamellae have lower carbon content.", "answer": "However, the average mass fraction of carbon in areas with dense lamellae is the same as that in areas with sparse lamellae.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出概念中的错误并进行纠正，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目考查对共析钢微观结构中碳含量分布的基本概念的理解和记忆，需要纠正错误观念并解释正确原理。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要理解珠光体组织的碳含量分布原理，但只需纠正一个常见的误解（密集区与稀疏区的碳含量差异），不需要进行复杂的分析或比较。主要考察对共析钢微观结构基础概念的掌握程度，属于\"概念解释和描述\"层次。", "convertible": true, "correct_option": "The average mass fraction of carbon in areas with dense lamellae is the same as that in areas with sparse lamellae.", "choice_question": "When observing the microstructure of eutectoid steel, it is found that the figure shows different densities of cementite lamellae. Which of the following statements is correct regarding the carbon content in these areas?", "conversion_reason": "The original short answer question presents a concept with an error and asks for correction. This can be effectively converted into a multiple-choice question by providing the correct statement as one of the options and other plausible but incorrect statements as distractors. The answer is a standard concept that can be presented as a choice.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The carbon content variation is due to local fluctuations in the eutectoid reaction kinetics", "B": "Dense lamellae regions result from higher cooling rates during transformation", "C": "The observed difference indicates non-uniform carbon distribution in the parent austenite", "D": "Sparse lamellae areas correspond to regions that underwent partial spheroidization" }, "correct_answer": "A", "explanation": "The correct answer is A because in eutectoid steel, the carbon content is uniform throughout (0.8wt%), and lamellae spacing variations are caused by local differences in transformation kinetics, not carbon content. Option B exploits the common misconception that cooling rate affects lamellae spacing in eutectoid steel (it actually affects undercooling and nucleation rate). Option C creates confusion by suggesting non-uniform carbon distribution, which contradicts the definition of eutectoid composition. Option D introduces a plausible-sounding but irrelevant process (spheroidization) that doesn't occur during normal eutectoid transformation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3997, "question": "Which kind of fracture (ductile or brittle) is associated with transgranular crack propagation?", "answer": "Transgranular fracture is brittle.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释哪种断裂类型与穿晶裂纹扩展相关，答案需要文字解释和论述，而不是从选项中选择或简单判断对错。 | 知识层次: 题目考查对断裂类型（韧性断裂和脆性断裂）及其与穿晶裂纹扩展关系的基本概念记忆和理解，属于基础概念层面的知识。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即\"穿晶断裂属于脆性断裂\"这一简单事实。不需要解释或分析多个概念，属于最基本的知识点回忆题。", "convertible": true, "correct_option": "brittle", "choice_question": "Which kind of fracture (ductile or brittle) is associated with transgranular crack propagation?", "conversion_reason": "The answer is a standard term (brittle) that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ductile fracture with significant plastic deformation", "B": "Brittle fracture with transgranular propagation", "C": "Ductile fracture along grain boundaries", "D": "Brittle fracture with intergranular propagation" }, "correct_answer": "B", "explanation": "Transgranular crack propagation typically occurs in brittle fractures where cracks cut through grains rather than following grain boundaries. Option A is incorrect because ductile fractures involve extensive plastic deformation but usually show dimpled rupture surfaces. Option C is a cognitive bias trap combining correct fracture type with wrong propagation path. Option D describes a real phenomenon (intergranular brittle fracture) but is the opposite of what the question asks.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 467, "question": "Cross-slip", "answer": "The slip process transitions from one slip plane to another along the same slip direction.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Cross-slip\"这一概念进行文字解释和论述，答案提供了详细的定义说明，符合简答题的特征 | 知识层次: 题目考查对Cross-slip这一基本概念的定义和简单解释，属于基础概念的记忆和理解层面，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"Cross-slip\"的基本定义，属于最基础的概念记忆层面。题目正确选项直接给出了该术语的标准定义描述，不需要进行任何概念比较或复杂推理，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The slip process transitions from one slip plane to another along the same slip direction.", "choice_question": "Which of the following best describes cross-slip?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The slip process transitions from one slip plane to another along the same slip direction", "B": "Dislocations move simultaneously on intersecting slip planes with different Burgers vectors", "C": "A screw dislocation changes its slip direction while maintaining the same slip plane", "D": "Edge dislocations bypass obstacles by climbing onto parallel slip planes" }, "correct_answer": "A", "explanation": "Cross-slip specifically involves screw dislocations moving from one slip plane to another parallel plane while maintaining the same slip direction (A). Option B describes conjugate slip, not cross-slip. Option C is impossible as slip direction is determined by the Burgers vector. Option D describes dislocation climb, a diffusion-mediated process unrelated to cross-slip. The high difficulty comes from requiring precise differentiation between similar dislocation motion mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3551, "question": "In a body-centered cubic structure with lattice constant a, can a dislocation with Burgers vector $a$ [100] decompose into $\\frac{a}{2}$ [111] + $\\frac{a}{2}$ [1-1-1]? ( )", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从选项中选择正确答案，且提供了明确的选项（A）作为答案。 | 知识层次: 题目涉及位错分解的判断，需要理解体心立方结构中的位错性质以及Burgers矢量的分解规则。虽然不涉及复杂的计算，但需要对位错分解的条件和原理有较好的理解，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，需要考生具备以下能力：", "convertible": true, "correct_option": "A", "choice_question": "In a body-centered cubic structure with lattice constant a, can a dislocation with Burgers vector $a$ [100] decompose into $\\frac{a}{2}$ [111] + $\\frac{a}{2}$ [1-1-1]?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because the vector sum matches and the decomposition reduces strain energy", "B": "No, because [100] is not a perfect dislocation in BCC crystals", "C": "Only at temperatures above the Debye temperature", "D": "Yes, but only if the dislocation line direction is [110]" }, "correct_answer": "A", "explanation": "The correct answer is A because the vector sum of the two partial dislocations equals the original Burgers vector (a[100] = a/2[111] + a/2[1-1-1]) and this decomposition reduces the total elastic strain energy. Option B exploits the common misconception about perfect dislocations in BCC. Option C uses temperature dependence as a plausible but irrelevant factor. Option D creates a specific condition trap that seems technically sound but isn't required for this decomposition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4518, "question": "Briefly explain the difference in molecular chemistry between silicone polymers and other polymeric materials.", "answer": "The backbone chain of most polymers consists of carbon atoms that are linked together. For the silicone polymers, this backbone chain is composed of silicon and oxygen atoms that alternate positions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要解释两种聚合物在分子化学上的差异，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对硅聚合物和其他聚合物分子化学差异的基本概念记忆和理解，涉及聚合物主链组成的简单对比，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目要求考生解释两种聚合物在分子化学上的差异，涉及基础概念的记忆和理解。虽然需要区分硅氧聚合物和其他聚合物的主链组成，但不需要复杂的分析或推理步骤，属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "The backbone chain of most polymers consists of carbon atoms that are linked together. For the silicone polymers, this backbone chain is composed of silicon and oxygen atoms that alternate positions.", "choice_question": "Which of the following accurately describes the difference in molecular chemistry between silicone polymers and other polymeric materials?", "conversion_reason": "The answer is a standard explanation that can be converted into a correct option for a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the accurate description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Silicone polymers have a backbone of alternating silicon-oxygen bonds, while most polymers have carbon-carbon backbones", "B": "Silicone polymers exhibit higher thermal conductivity due to their silicon-oxygen backbone structure", "C": "The presence of silicon atoms gives silicone polymers higher crystallinity than conventional polymers", "D": "Silicone polymers achieve their flexibility through carbon double bonds in the backbone" }, "correct_answer": "A", "explanation": "The correct answer is A because silicone polymers are uniquely characterized by their silicon-oxygen backbone, while most polymers have carbon-based backbones. Option B is incorrect because thermal conductivity is not directly determined by the backbone composition. Option C exploits the common misconception that silicon content automatically increases crystallinity, while in reality silicones are typically amorphous. Option D creates confusion by suggesting a carbon-based mechanism for silicone's flexibility, when it actually comes from the long Si-O bond length and bond angles.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 420, "question": "3. The factors influencing the formation of substitutional solid solutions include _ (6)", "answer": "Ionic size", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写影响置换固溶体形成的因素，需要简要回答具体因素（如离子尺寸），属于简答题类型 | 知识层次: 题目考查对形成置换固溶体的影响因素的基本概念记忆，如离子尺寸等，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求识别影响置换固溶体形成的因素之一（离子尺寸），属于基础概念记忆层次。题目仅需回忆单一知识点，无需解释或比较多个概念，解题步骤简单直接，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "Ionic size", "choice_question": "Which of the following factors influences the formation of substitutional solid solutions?", "conversion_reason": "The answer is a standard term (Ionic size) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ionic size", "B": "Crystal symmetry", "C": "Thermal conductivity", "D": "Electronegativity difference < 0.3" }, "correct_answer": "A", "explanation": "The correct answer is A (Ionic size) because the Hume-Rothery rules state that atomic/ionic size difference must be less than 15% for substitutional solid solutions to form. B (Crystal symmetry) is a cognitive bias trap - while important for phase stability, it doesn't directly govern substitutional solubility. C (Thermal conductivity) is a professional intuition trap - it's a materials property unrelated to atomic substitution. D (Electronegativity difference < 0.3) is a multi-level verification trap - while electronegativity matters, the 0.3 threshold applies to interstitial solutions, not substitutional ones.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3666, "question": "Calculate the length of the Burgers vector in diamond cubic silicon", "answer": "b = 3.840 Å", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算Burgers vector的长度），答案是一个具体的数值结果（3.840 Å），这符合计算题的特征。 | 知识层次: 题目需要计算Burgers向量的长度，这涉及到对晶体结构（金刚石立方硅）的理解以及相关公式的应用。虽然计算本身可能不复杂，但需要理解Burgers向量的定义、晶体结构的知识以及如何将这些知识应用到具体材料中。这属于中等应用层次，因为它需要多步计算和概念关联。 | 难度: 在选择题中属于中等偏上难度，需要理解Burgers向量的概念，知道金刚石立方结构硅的晶格常数，并能正确计算Burgers向量的长度。这涉及到多个步骤的计算和对晶体结构概念的综合应用。", "convertible": true, "correct_option": "3.840 Å", "choice_question": "What is the length of the Burgers vector in diamond cubic silicon?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.840 Å", "B": "5.431 Å", "C": "2.715 Å", "D": "1.920 Å" }, "correct_answer": "A", "explanation": "The correct answer is A (3.840 Å) because the Burgers vector in diamond cubic silicon is a/2√2, where a is the lattice parameter (5.431 Å). Option B (5.431 Å) is the lattice parameter itself, a common mistake when confusing Burgers vector with unit cell dimensions. Option C (2.715 Å) is half the lattice parameter, exploiting the tendency to oversimplify the √2 factor. Option D (1.920 Å) is half the correct value, targeting those who miscalculate the vector components.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4319, "question": "Briefly explain why, upon solidification, an alloy of eutectic composition forms a microstructure consisting of alternating layers of the two solid phases.", "answer": "Upon solidification, an alloy of eutectic composition forms a microstructure consisting of alternating layers\nof the two solid phases because during the solidification atomic diffusion must occur, and with this layered configuration the diffusion path length for the atoms is a minimum.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释共晶合金凝固时形成交替层状微观结构的原因，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释共晶合金凝固过程中微观结构形成的机理，涉及原子扩散和能量最小化原理的综合分析，需要深入理解相变过程和微观组织形成的原理，属于机理层面的解释。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅要理解合金凝固的基本原理，还需要掌握共晶成分合金的微观结构形成机理。正确选项涉及原子扩散路径最小化的概念，这需要考生将扩散理论与微观结构形成联系起来进行综合分析。这种题目在选择题中属于需要机理深度解释的类型，比单纯记忆概念或简单应用公式的题目难度更高。", "convertible": true, "correct_option": "Upon solidification, an alloy of eutectic composition forms a microstructure consisting of alternating layers of the two solid phases because during the solidification atomic diffusion must occur, and with this layered configuration the diffusion path length for the atoms is a minimum.", "choice_question": "Why does an alloy of eutectic composition form a microstructure consisting of alternating layers of the two solid phases upon solidification?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The layered structure minimizes the diffusion path length during solid-state phase separation", "B": "The alternating layers form to maximize interfacial energy between the phases", "C": "The eutectic reaction requires simultaneous nucleation of both phases in a periodic pattern", "D": "The layered morphology results from preferential crystal growth along specific crystallographic directions" }, "correct_answer": "A", "explanation": "The correct answer is A because the alternating layered structure indeed minimizes diffusion distances during solidification, which is energetically favorable. Option B is incorrect because the system actually minimizes interfacial energy, not maximizes it. Option C is a cognitive bias trap - while nucleation is important, the periodicity is not an inherent requirement. Option D exploits a common intuition about crystal growth directions, but this is not the primary reason for the layered structure in eutectics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3544, "question": "What are the characteristics of Babbitt alloy in terms of lubrication principle?", "answer": "It belongs to friction under the lubricating film. In terms of lubrication principle, it relies on the lubricating film formed between the shaft and the bearing bush to reduce the friction coefficient, thereby minimizing wear between the shaft and the bearing bush.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释Babbitt合金在润滑原理方面的特性，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查Babbitt合金在润滑原理方面的基本特性，属于对材料基本概念和原理的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解Babbitt合金的润滑原理，并能够描述润滑膜的形成及其作用。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "It belongs to friction under the lubricating film. In terms of lubrication principle, it relies on the lubricating film formed between the shaft and the bearing bush to reduce the friction coefficient, thereby minimizing wear between the shaft and the bearing bush.", "choice_question": "Which of the following describes the characteristics of Babbitt alloy in terms of lubrication principle?", "conversion_reason": "The answer is a standard description of the lubrication principle of Babbitt alloy, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description among given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It belongs to friction under the lubricating film, relying on the lubricating film formed between the shaft and the bearing bush to reduce friction", "B": "It exhibits solid lubrication properties due to the low shear strength of tin crystals in its microstructure", "C": "It functions through hydrodynamic lubrication where the rotating shaft creates a pressurized oil film", "D": "It operates on boundary lubrication principles where direct metal-to-metal contact occurs through protective oxide layers" }, "correct_answer": "A", "explanation": "The correct answer is A because Babbitt alloy's lubrication mechanism specifically relies on the formation of a lubricating film between moving parts. Option B is a cognitive bias trap - while Babbitt contains tin, its lubrication doesn't come from tin's crystal structure. Option C is a professional intuition trap - hydrodynamic lubrication requires different conditions than Babbitt's typical operation. Option D is a multi-level verification trap - while oxide layers exist, they're not the primary lubrication mechanism in Babbitt alloys.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4430, "question": "Cadmium sulfide (CdS) has a cubic unit cell, and from x-ray diffraction data it is known that the cell edge length is 0.582nm. If the measured density is 4.82g / {cm}^{3}, how many \\mathrm{Cd}^{2+} and \\mathrm{S}^{2-} ions are there per unit cell?", "answer": "there are four \\mathrm{cd}^{2+} and four s^{2-} ions per unit cell.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用（如密度公式、单位晶胞体积计算等）来确定单位晶胞中的离子数量，答案是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括利用晶胞边长计算体积、密度公式的应用以及离子数量的推导，涉及概念关联和综合分析。虽然不涉及复杂的推理分析或机理解释，但需要一定的思维深度和计算步骤。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、密度计算和化学计量比等多个概念，并进行多步计算和综合分析。虽然题目提供了正确选项，但解题过程涉及单位转换、摩尔质量计算和离子数目的推导，步骤较为复杂。", "convertible": true, "correct_option": "there are four Cd²⁺ and four S²⁻ ions per unit cell", "choice_question": "Cadmium sulfide (CdS) has a cubic unit cell with a cell edge length of 0.582 nm and a measured density of 4.82 g/cm³. How many Cd²⁺ and S²⁻ ions are there per unit cell?", "conversion_reason": "The answer is a specific and discrete value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4 Cd²⁺ and 4 S²⁻ ions", "B": "2 Cd²⁺ and 2 S²⁻ ions", "C": "8 Cd²⁺ and 8 S²⁻ ions", "D": "1 Cd²⁺ and 1 S²⁻ ion" }, "correct_answer": "A", "explanation": "The correct answer is A because the density calculation confirms a zinc blende structure with 4 formula units per unit cell. Option B is a common mistake when assuming a simple cubic structure. Option C exploits the misconception that face-centered cubic packing requires 8 ions. Option D is a trap for those who confuse unit cell content with primitive cell content.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3140, "question": "What are the conditions for the occurrence of secondary recrystallization (abnormal growth)?", "answer": "The conditions for its occurrence are the presence of recrystallization texture, second-phase particles, or surface thermal grooves.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述二次再结晶（异常生长）发生的条件，答案提供了文字解释而非选择、判断或计算。 | 知识层次: 题目考查对二次再结晶（异常生长）发生条件的基本概念记忆，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆，但需要考生掌握\"二次再结晶\"发生的三个具体条件（再结晶织构、第二相颗粒、表面热沟槽），属于对多个相关要素的联合记忆。相比单纯记忆定义（等级1），该题要求对概念条件进行完整描述；但尚未达到需要阐述复杂机理或比较分析的等级3水平。在选择题型中，这类题目需要考生对知识点有较全面的记忆而非简单识别。", "convertible": true, "correct_option": "The presence of recrystallization texture, second-phase particles, or surface thermal grooves.", "choice_question": "Which of the following are the conditions for the occurrence of secondary recrystallization (abnormal growth)?", "conversion_reason": "The answer is a standard set of conditions that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The presence of recrystallization texture, second-phase particles, or surface thermal grooves", "B": "High stacking fault energy and uniform dislocation distribution", "C": "Isothermal holding above 0.8Tm with rapid quenching", "D": "Simultaneous satisfaction of Hall-Petch relationship and Schmid factor" }, "correct_answer": "A", "explanation": "Correct answer A lists the three scientifically established conditions for secondary recrystallization: texture provides preferred growth directions, second-phase particles inhibit normal grain growth, and surface grooves create energy gradients. Option B exploits cognitive bias by using dislocation-related terms that apply to primary recrystallization but not abnormal growth. Option C is an intuition trap combining legitimate heat treatment parameters in an irrelevant context. Option D is a multi-level verification trap using valid materials science relationships that don't govern recrystallization mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4234, "question": "What is the composition, in atom percent, of an alloy that consists of 97 wt% Fe and 3 wt% Si?", "answer": "the composition of the alloy is 94.2 at% fe and 5.8 at% si.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用（将重量百分比转换为原子百分比），答案以具体数值形式给出，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及原子百分比和重量百分比之间的转换，需要应用相关公式并理解其物理意义，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解质量百分比与原子百分比之间的转换关系，涉及多步计算（包括分子量计算、摩尔数转换等），并需要综合分析合金成分的转换过程。虽然题目给出了正确选项，但解题过程仍需要较强的概念关联和计算能力。", "convertible": true, "correct_option": "the composition of the alloy is 94.2 at% fe and 5.8 at% si", "choice_question": "What is the composition, in atom percent, of an alloy that consists of 97 wt% Fe and 3 wt% Si?", "conversion_reason": "The answer is a specific and deterministic calculation result, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "94.2 at% Fe and 5.8 at% Si", "B": "96.1 at% Fe and 3.9 at% Si", "C": "97.0 at% Fe and 3.0 at% Si", "D": "92.5 at% Fe and 7.5 at% Si" }, "correct_answer": "A", "explanation": "The correct answer requires proper conversion from weight percent to atom percent using atomic weights (Fe: 55.85 g/mol, Si: 28.09 g/mol). Option B is a common mistake from incorrectly assuming linear conversion. Option C directly uses weight percentages without conversion, exploiting the AI's potential oversight of unit differences. Option D introduces a significant deviation that might trick models relying on approximate calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4288, "question": "A cylindrical specimen of cold-worked copper has a ductility (%EL) of 25%. If its cold-worked radius is 10mm (0.40 in.), what was its radius before deformation?", "answer": "the radius before deformation was 10.6mm (0.424 in.).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定变形前的圆柱形铜试样的半径。答案给出了具体的数值结果，表明这是一个计算题。 | 知识层次: 题目需要进行多步计算，涉及冷加工前后材料性能变化的关联分析，需要理解并应用相关公式来推导变形前的半径，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解冷加工对材料性能的影响，掌握延展性(%EL)与变形前后尺寸的关系，并进行多步计算推导原始尺寸。虽然题目提供了正确选项减少了计算量，但仍需综合分析材料科学原理和数学关系才能正确解答。", "convertible": true, "correct_option": "10.6mm (0.424 in.)", "choice_question": "A cylindrical specimen of cold-worked copper has a ductility (%EL) of 25%. If its cold-worked radius is 10mm (0.40 in.), what was its radius before deformation?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "10.6mm (0.424 in.)", "B": "11.2mm (0.441 in.)", "C": "9.8mm (0.386 in.)", "D": "12.5mm (0.492 in.)" }, "correct_answer": "A", "explanation": "正确答案A基于冷加工铜的塑性变形体积不变原理计算得出。干扰项B利用了常见的面积收缩率计算错误，将塑性变形误认为线性收缩；干扰项C设计为反向计算错误，诱使忽略冷加工导致的密度变化；干扰项D利用直觉上高延展性对应大变形量的认知偏差，但实际忽略了铜的加工硬化特性。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1367, "question": "Analyze the fundamental differences in work hardening", "answer": "Work hardening: Possible mechanisms include dislocation pile-up, forest dislocation resistance, and the consumption of external force work through the formation of jogs.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析工作硬化的基本差异，答案提供了文字解释和论述，没有涉及选项选择、对错判断或数值计算 | 知识层次: 题目要求分析加工硬化的基本差异，涉及位错堆积、森林位错阻力等机制的解释，需要综合运用材料科学知识进行推理分析和机理解释，思维深度较高。 | 难度: 在选择题型中，该题目要求考生对工作硬化的多种机制（如位错堆积、森林位错阻力、外力功消耗等）有深入的理解，并能综合运用这些知识进行复杂现象的分析。这需要考生具备较高的机理解释能力和综合分析能力，属于选择题型中的高难度题目。", "convertible": true, "correct_option": "Work hardening: Possible mechanisms include dislocation pile-up, forest dislocation resistance, and the consumption of external force work through the formation of jogs.", "choice_question": "Which of the following describes the fundamental differences in work hardening?", "conversion_reason": "The answer is a standard explanation of work hardening mechanisms, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Work hardening: Possible mechanisms include dislocation pile-up, forest dislocation resistance, and the consumption of external force work through the formation of jogs", "B": "Work hardening primarily results from the reduction of grain boundaries leading to increased dislocation mobility", "C": "The Hall-Petch relationship quantitatively describes work hardening by correlating yield strength with dislocation density", "D": "Work hardening is fundamentally a thermal activation process where stored energy is released as heat during deformation" }, "correct_answer": "A", "explanation": { "correct_answer": "Option A accurately describes the fundamental mechanisms of work hardening including key processes like dislocation interactions and energy consumption.", "B": "This option exploits the common misconception that reduced grain boundaries enhance hardening, when in reality work hardening occurs within grains via dislocation mechanisms.", "C": "This traps AI by conflating the Hall-Petch relationship (which relates strength to grain size) with work hardening mechanisms.", "D": "This targets the intuitive but incorrect assumption that work hardening involves significant thermal activation, when it's primarily a mechanical energy storage process." }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1000, "question": "Assuming that the slip system that can be activated in a face-centered cubic crystal is (111)[011], if the slip dislocation is a pure edge dislocation, please indicate the direction of its dislocation line.", "answer": "The direction of the dislocation line for a pure edge dislocation is perpendicular to $\\vec{b}$ and lies on the slip plane, which is [211].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案需要详细说明位错线的方向及其与滑移面和滑移方向的关系，而不是简单的选择或判断。 | 知识层次: 题目要求理解面心立方晶体中的滑移系统、纯刃位错的性质，并能够确定位错线的方向。这需要将多个概念（滑移系统、位错类型、位错线方向）关联起来进行分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要理解多个概念并进行多步计算和综合分析。题目要求考生掌握面心立方晶体中的滑移系统、纯刃位错的性质以及位错线与滑移面和柏氏矢量的关系。解题步骤包括确定滑移面(111)、滑移方向[011]，然后根据纯刃位错的定义（位错线垂直于柏氏矢量且位于滑移面上）推导位错线方向[211]。这需要将多个晶体学概念关联起来并进行空间几何分析，超出了简单记忆或单一概念应用的范畴。", "convertible": true, "correct_option": "[211]", "choice_question": "Assuming that the slip system that can be activated in a face-centered cubic crystal is (111)[011], if the slip dislocation is a pure edge dislocation, what is the direction of its dislocation line?", "conversion_reason": "The answer is a standard term (direction vector) which can be presented as a clear option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[110]", "B": "[211]", "C": "[111]", "D": "[011]" }, "correct_answer": "B", "explanation": "The correct answer is [211] because for a pure edge dislocation in the (111)[011] slip system, the dislocation line direction must be perpendicular to the Burgers vector [011] and lie in the slip plane (111). The cross product of the slip plane normal [111] and Burgers vector [011] gives [211]. Option A [110] is a common FCC direction but not perpendicular to [011]. Option C [111] is the slip plane normal, not the dislocation line. Option D [011] is the Burgers vector itself, which cannot be parallel to the dislocation line for an edge dislocation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2334, "question": "What type of solid solution is formed when hydrogen atoms dissolve in aluminum?", "answer": "The crystal structure of aluminum is fcc. From the appendix, the radius of the hydrogen atom is found to be rH=0.046nm, and the radius of the aluminum atom is rAl=0.143nm. The radius ratio rH/rAl=0.046/0.143=0.32.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释氢原子溶解在铝中形成的固溶体类型，答案提供了晶体结构、原子半径比等文字解释和论述，没有涉及选项选择、对错判断或具体数值计算。 | 知识层次: 题目需要应用基本的半径比计算来判断固溶体类型，属于直接套用基本公式和简单计算的范畴，不涉及多步计算或复杂分析。 | 难度: 在选择题中属于较低难度，题目仅要求简单应用基本公式进行计算（半径比计算），并直接套用已知数据（原子半径）。解题步骤简单直接，无需复杂分析或概念整合。", "convertible": true, "correct_option": "Interstitial solid solution", "choice_question": "What type of solid solution is formed when hydrogen atoms dissolve in aluminum?", "conversion_reason": "The answer is a standard term in materials science (Interstitial solid solution), which can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial solid solution", "B": "Substitutional solid solution", "C": "Intermetallic compound", "D": "Eutectic mixture" }, "correct_answer": "A", "explanation": "The correct answer is A because hydrogen atoms are small enough to occupy the interstitial sites in the aluminum lattice, forming an interstitial solid solution. Option B is designed to exploit the cognitive bias where one might assume all solid solutions are substitutional. Option C is a professional intuition trap, as intermetallic compounds form between metals, not between a metal and a non-metal like hydrogen. Option D is a multi-level verification trap, as eutectic mixtures involve liquid phases, not solid solutions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1453, "question": "After cold plastic deformation, the strength and hardness of metal (40)", "answer": "increase", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（冷塑性变形后金属的强度和硬度增加），并要求判断其正确性。答案\"increase\"是对该陈述的肯定判断，符合判断题的特征。 | 知识层次: 题目考查冷塑性变形对金属强度和硬度影响的基本概念记忆，属于材料科学中最基础的知识点之一，无需复杂分析或计算。 | 难度: 该题目属于基础概念记忆层次，仅需判断冷塑性变形后金属强度和硬度的变化趋势。正确选项\"increase\"是材料科学中最基础的概念之一，无需复杂分析或推理，属于选择题型中最简单的正误判断类型。", "convertible": true, "correct_option": "increase", "choice_question": "After cold plastic deformation, the strength and hardness of metal (40)", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All metals will exhibit increased strength and hardness after cold plastic deformation, regardless of their crystal structure.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most metals show increased strength and hardness after cold working due to dislocation accumulation, some materials with specific crystal structures (like certain shape memory alloys) may behave differently. The absolute term 'all' makes this statement false as there are exceptions in material science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1749, "question": "In a ternary system phase diagram, if there are n boundary lines, then the number of connecting lines that can be drawn in this phase diagram is . a. 3 b. n - 1 c. n d. n+1", "answer": "c", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的选项（a. 3 b. n - 1 c. n d. n+1）中选择正确答案，符合选择题的特征。 | 知识层次: 题目考查对三元相图中边界线和连接线数量关系的基本概念记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（三元系统相图的边界线和连接线数量关系），但需要考生理解相图的基本构造原理和边界线与连接线之间的对应关系，而不仅仅是简单的定义记忆。正确选项需要考生通过基本概念的理解进行简单辨析，因此属于等级2难度。", "convertible": true, "correct_option": "c", "choice_question": "In a ternary system phase diagram, if there are n boundary lines, then the number of connecting lines that can be drawn in this phase diagram is .", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The number of connecting lines equals the number of phase regions minus one", "B": "The number of connecting lines is always equal to the number of boundary lines (n)", "C": "The number of connecting lines is determined by the Gibbs phase rule (F=C-P+2)", "D": "The number of connecting lines equals twice the number of invariant points" }, "correct_answer": "B", "explanation": "The correct answer is B because in ternary phase diagrams, each boundary line represents a connection between two phase regions, making the number of connecting lines equal to the number of boundary lines. Option A is a cognitive bias trap, using an incorrect analogy with binary phase diagrams. Option C exploits professional intuition by misapplying the Gibbs phase rule to line counting. Option D creates a multi-level verification trap by introducing invariant points which are irrelevant to line counting.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 294, "question": "What is homogeneous nucleation?", "answer": "Homogeneous nucleation occurs in a uniform medium, where the probability of nucleation is the same throughout the entire medium, independent of interfaces or defects.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"homogeneous nucleation\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即均匀成核的定义和基本特征，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目仅要求识别和记忆\"均质形核\"的基本定义，属于最基础的概念记忆层次。正确选项直接给出了定义性描述，无需进行概念比较或复杂推理，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Homogeneous nucleation occurs in a uniform medium, where the probability of nucleation is the same throughout the entire medium, independent of interfaces or defects.", "choice_question": "Which of the following best describes homogeneous nucleation?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Homogeneous nucleation occurs in a uniform medium, where the probability of nucleation is the same throughout the entire medium, independent of interfaces or defects.", "B": "Homogeneous nucleation is the formation of nuclei at preferential sites such as grain boundaries or dislocations due to lower energy barriers.", "C": "Homogeneous nucleation describes the process where nucleation rate is controlled by external factors like temperature gradients or mechanical stress.", "D": "Homogeneous nucleation refers to the simultaneous formation of multiple nuclei with identical crystallographic orientations in a material." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines homogeneous nucleation as occurring uniformly without preferential sites. Option B incorrectly describes heterogeneous nucleation by mentioning preferential sites. Option C introduces external control factors which are irrelevant to the fundamental definition. Option D creates confusion by mixing the concept with crystallographic orientation, which is not part of nucleation classification criteria. These distractors exploit common misconceptions about nucleation mechanisms in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3303, "question": "What is the microstructural transformation of quenched steel during tempering at 20-100°C?", "answer": "Carbon segregation in martensite", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释淬火钢在20-100°C回火过程中的微观结构转变，答案需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目涉及对淬火钢在回火过程中微观结构转变的理解，需要将马氏体中的碳偏析现象与回火温度范围联系起来，属于中等应用层次的知识。这需要一定的概念关联和综合分析能力，而不仅仅是基础概念的记忆。 | 难度: 在选择题中属于中等难度，需要理解淬火钢在回火过程中的微观结构转变，并能够将碳在马氏体中的偏析现象与特定温度范围（20-100°C）联系起来。这要求考生掌握马氏体回火的基本知识，并能将温度范围与具体的结构变化对应起来，属于中等应用层次的知识运用。", "convertible": true, "correct_option": "Carbon segregation in martensite", "choice_question": "What is the microstructural transformation of quenched steel during tempering at 20-100°C?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Carbon segregation in martensite", "B": "Formation of ε-carbides", "C": "Recovery of dislocations", "D": "Decomposition of retained austenite" }, "correct_answer": "A", "explanation": "The correct answer is A because at 20-100°C, the primary transformation is carbon clustering/segregation within the martensite lattice. Option B is incorrect because ε-carbide formation typically occurs at higher temperatures (100-250°C). Option C is wrong as dislocation recovery requires higher thermal activation energy. Option D is misleading as retained austenite decomposition happens above 200°C. The interference items exploit common misconceptions about the temperature ranges for different tempering stages.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2881, "question": "In practice, it is often considered that the grain size of steel will significantly grow when heated to 870°C. If the original grain diameter of the steel is 0.05 mm, the empirical formula for grain growth is D^(1/n)−D0^(1/n)=c t, where D is the grown grain diameter; D0 is the original grain diameter; c is the proportional constant; t is the holding time. Given that at 870°C, n=0.2, c=2×10^(−8), find the grain diameter of steel with 0.8% carbon content after holding at 870°C for 1 hour.", "answer": "At 870°C: D^5=(0.05)^5+2×10^(−8)×60=1.513×10^(−6) D=0.0686(mm). Compared to the original grain diameter, it has significantly grown (approximately 37%).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出具体的数值结果（0.0686 mm），属于典型的计算题。 | 知识层次: 题目需要进行多步计算，包括代入公式、单位转换和数值求解，同时需要理解晶粒生长的经验公式及其参数的含义。虽然不涉及复杂的综合分析或机理解释，但比简单的直接套用公式更具挑战性。 | 难度: 在选择题中属于中等偏上难度，需要理解并应用晶粒生长经验公式，进行多步骤计算（包括指数运算和单位转换），同时需要综合分析计算结果与原始数据的对比关系。题目涉及材料科学中的具体应用场景，要求考生具备将理论公式与实际问题相结合的能力。", "convertible": true, "correct_option": "0.0686 mm", "choice_question": "In practice, it is often considered that the grain size of steel will significantly grow when heated to 870°C. If the original grain diameter of the steel is 0.05 mm, the empirical formula for grain growth is D^(1/n)−D0^(1/n)=c t, where D is the grown grain diameter; D0 is the original grain diameter; c is the proportional constant; t is the holding time. Given that at 870°C, n=0.2, c=2×10^(−8), find the grain diameter of steel with 0.8% carbon content after holding at 870°C for 1 hour.", "conversion_reason": "The question involves a calculation with a definite numerical answer, making it suitable for conversion to a multiple-choice format where the correct option is the calculated grain diameter.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0686 mm", "B": "0.0524 mm", "C": "0.0892 mm", "D": "0.0437 mm" }, "correct_answer": "A", "explanation": "正确答案A是通过正确应用晶粒生长经验公式计算得出的。干扰项B利用了常见的认知偏差，即低估高温下晶粒生长的速率，仅考虑了短时间效应。干扰项C设计为过度补偿效应，模拟了AI可能错误地将n值取倒数的情况。干扰项D是一个反直觉陷阱，模拟了AI可能错误地将温度效应反向计算的情况。每个干扰项都针对AI模型中可能存在的特定计算路径错误进行了优化设计。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4463, "question": "Are thermal stresses introduced upon heating? Why or why not?", "answer": "Yes, thermal stresses will be introduced because of thermal expansion upon heating for the same reason as for thermal contraction upon cooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目需要文字解释和论述，答案提供了详细的解释说明为什么加热会引入热应力，符合简答题的特征。 | 知识层次: 题目考查对热应力产生原因的基本概念记忆和理解，仅需解释热膨胀导致热应力的基本原理，无需复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆（热应力与热膨胀的关系），但需要学生理解并解释\"加热时会产生热应力\"的原因，这比单纯记忆定义（等级1）要求更高。题目正确选项不仅陈述了现象，还通过类比冷却过程解释了原理，要求学生掌握概念间的关联性，但不需要进行复杂体系分析（等级3）。", "convertible": true, "correct_option": "Yes, thermal stresses will be introduced because of thermal expansion upon heating for the same reason as for thermal contraction upon cooling.", "choice_question": "Are thermal stresses introduced upon heating?", "conversion_reason": "The answer is a clear and concise explanation that can serve as a correct option in a multiple-choice format. The question can be directly used as a multiple-choice question by providing the correct answer as one of the options and adding plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, due to differential thermal expansion between constrained regions", "B": "No, because heating always causes uniform expansion relieving stresses", "C": "Only in anisotropic materials with negative thermal expansion coefficients", "D": "Only if the heating rate exceeds the material's thermal diffusivity" }, "correct_answer": "A", "explanation": "Correct answer A identifies the key mechanism of thermal stress generation through constrained differential expansion. Option B exploits the common misconception that heating uniformly relieves stresses, ignoring constraint conditions. Option C uses the rare case of negative thermal expansion materials as a red herring. Option D creates confusion by mixing thermal stress with transient thermal gradient effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 678, "question": "How does the effect of solute elements on the melting point of alloys influence the diffusion coefficient?", "answer": "Solute elements that can lower the melting point of alloys (or cause a decrease in the liquidus line) will increase the diffusion coefficient; conversely, they will decrease the diffusion coefficient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释溶质元素对合金熔点的影响如何影响扩散系数，答案提供了文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求分析溶质元素对合金熔点的影响如何进一步影响扩散系数，涉及多个概念的关联和机理解释，需要综合运用材料科学中的热力学和动力学知识进行推理分析。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Solute elements that can lower the melting point of alloys (or cause a decrease in the liquidus line) will increase the diffusion coefficient; conversely, they will decrease the diffusion coefficient.", "choice_question": "How does the effect of solute elements on the melting point of alloys influence the diffusion coefficient?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solute elements lowering the melting point increase vacancy concentration, thereby enhancing diffusion", "B": "Solute elements always decrease diffusion by creating strain fields that impede atomic motion", "C": "The effect depends solely on atomic size mismatch, not melting point depression", "D": "Higher melting point alloys inherently have greater lattice vibration frequencies that dominate diffusion" }, "correct_answer": "A", "explanation": "Correct answer A captures the key relationship where melting point depression increases vacancy concentration (via the Arrhenius relationship), which is the primary driver for enhanced diffusion. B is a cognitive bias trap - while strain fields do impede diffusion, this ignores the dominant vacancy mechanism. C exploits a common materials science confusion by overemphasizing size effects. D is a multi-level trap combining correct lattice vibration theory with incorrect application to diffusion mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3978, "question": "During the recovery of a cold-worked material, is the electrical conductivity recovered to its precold-worked state?", "answer": "The electrical conductivity is recovered to its precold-worked state.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（是否恢复到冷加工前的状态），答案直接给出了对陈述的判断（是/否）。这符合判断题的特征。 | 知识层次: 题目考查对冷加工材料恢复过程中电导率变化的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即冷加工材料恢复过程中电导率是否恢复到冷加工前状态的简单正误判断。题目仅要求考生回忆和识别基本定义或原理，无需深入理解或分析多个概念，因此属于最低难度等级。", "convertible": true, "correct_option": "The electrical conductivity is recovered to its precold-worked state.", "choice_question": "During the recovery of a cold-worked material, is the electrical conductivity recovered to its precold-worked state?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "During the recovery of a cold-worked material, the electrical conductivity is always fully recovered to its precold-worked state regardless of the annealing conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While recovery generally improves electrical conductivity by reducing point defect concentration and dislocation density, full recovery to the precold-worked state depends on proper annealing conditions (temperature, time, and atmosphere). The use of 'always' makes this statement false as incomplete recovery can occur with insufficient annealing. Additionally, some residual defects may persist even after recovery, preventing complete restoration of conductivity.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4327, "question": "What is the carbon concentration of an iron-carbon alloy for which the fraction of total ferrite is 0.94 ?", "answer": "the carbon concentration of the iron-carbon alloy is 0.42 \\text{ wt% c}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算铁碳合金的碳浓度，需要通过给定的铁素体分数（0.94）进行数值计算，并应用相关公式得出具体数值（0.42 wt% C）。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用铁碳相图的相关知识，通过给定的铁素体分数来计算碳浓度，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要综合运用铁碳相图知识、杠杆定律计算以及相分数与成分的关系。解题步骤包括：1) 理解总铁素体分数含义；2) 确定相关相区；3) 应用杠杆定律建立方程；4) 解方程求碳浓度。虽然计算过程明确，但需要准确关联多个概念，且容易在相边界值判断上出错，属于典型的综合性计算问题。", "convertible": true, "correct_option": "0.42 wt% c", "choice_question": "What is the carbon concentration of an iron-carbon alloy for which the fraction of total ferrite is 0.94?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.42 wt% C", "B": "0.76 wt% C", "C": "0.94 wt% C", "D": "0.25 wt% C" }, "correct_answer": "A", "explanation": "The correct answer is A (0.42 wt% C) because it is derived from the lever rule calculation for the given ferrite fraction in the iron-carbon phase diagram. Option B (0.76 wt% C) exploits the eutectoid composition misconception. Option C (0.94 wt% C) creates a numerical trap by matching the given fraction value. Option D (0.25 wt% C) targets the common confusion between ferrite fraction and carbon solubility limit in ferrite.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1635, "question": "According to the different atomic arrangement structures at the interface, the phase interfaces in solids can be divided into _(17), (18), and (19) interfaces.", "answer": "(17) coherent; (18) incoherent; (19) semi-coherent", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写空缺部分，需要根据知识进行文字回答，而不是从选项中选择或判断对错。 | 知识层次: 题目考查对固体中相界面分类的基本概念记忆，属于定义和分类的基础知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目要求考生记忆并区分固体中相界面的三种基本类型（共格、非共格和半共格界面），这属于基础概念的记忆性知识，无需复杂的理解或分析过程。选择题型中仅需识别正确选项，无需进一步解释或推导，因此难度较低。", "convertible": true, "correct_option": "coherent, incoherent, and semi-coherent", "choice_question": "According to the different atomic arrangement structures at the interface, the phase interfaces in solids can be divided into:", "conversion_reason": "The short answer question asks for standard terms (coherent, incoherent, semi-coherent) which can be presented as options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "coherent, incoherent, and semi-coherent", "B": "elastic, plastic, and viscoelastic", "C": "ionic, covalent, and metallic", "D": "dislocation, grain boundary, and stacking fault" }, "correct_answer": "A", "explanation": "The correct answer is A because phase interfaces in solids are classified based on atomic arrangement mismatch at the interface into coherent (perfect match), incoherent (no match), and semi-coherent (partial match). Option B incorrectly uses mechanical deformation terms. Option C erroneously lists primary atomic bond types. Option D wrongly substitutes common crystal defects for interface classification types. These distractors exploit material science novices' tendency to confuse related but distinct classification systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2982, "question": "Given erf(0.71)=0.68, find the value of x/(2√(Dt)).", "answer": "x/(2√(Dt)) = 0.71.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目给出了一个数学函数的值（erf(0.71)=0.68），并要求根据这个信息计算x/(2√(Dt))的值。解答过程需要应用数学公式和数值计算，最终得出一个具体的数值结果（0.71）。这符合计算题的特征。 | 知识层次: 题目仅需要直接应用给定的误差函数值(erf)和公式x/(2√(Dt))进行计算，属于基本公式的直接套用，无需多步计算或综合分析。 | 难度: 在选择题中属于最低难度，题目直接给出了erf函数的数值和对应的参数，只需要简单套用公式x/(2√(Dt)) = 0.71即可得出答案。无需任何额外的计算或公式组合，属于单一公式直接计算的类型。", "convertible": true, "correct_option": "0.71", "choice_question": "Given erf(0.71)=0.68, what is the value of x/(2√(Dt))?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.71", "B": "0.68", "C": "1.42", "D": "0.355" }, "correct_answer": "A", "explanation": "The correct answer is A (0.71) because the error function erf(z) is defined such that when z=0.71, erf(0.71)=0.68. Here z=x/(2√(Dt)). Option B (0.68) is a cognitive bias trap - it's the output value of erf but not the input argument. Option C (1.42) exploits intuition by doubling the correct value, playing on the common mistake of confusing input/output relationships. Option D (0.355) is half the correct value, targeting those who might incorrectly manipulate the equation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1034, "question": "Compositional supercooling", "answer": "Compositional supercooling: During the solidification of an alloy solution, the theoretical solidification temperature remains unchanged, and the degree of supercooling is entirely determined by the distribution of solute components. This type of supercooling is called compositional supercooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Compositional supercooling\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即compositional supercooling的定义和基本原理，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并描述\"compositional supercooling\"的定义和基本原理。题目要求考生不仅知道这个术语，还要能够解释其背后的物理机制（如固溶体凝固过程中溶质分布对过冷度的影响）。这比简单的定义识别（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Compositional supercooling: During the solidification of an alloy solution, the theoretical solidification temperature remains unchanged, and the degree of supercooling is entirely determined by the distribution of solute components. This type of supercooling is called compositional supercooling.", "choice_question": "下列关于compositional supercooling的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Compositional supercooling occurs when solute redistribution creates a local depression of the liquidus temperature ahead of the solidification front", "B": "Compositional supercooling is primarily caused by rapid cooling rates that exceed the critical cooling rate for glass formation", "C": "This phenomenon requires the presence of at least three alloying elements to establish sufficient concentration gradients", "D": "Compositional supercooling can be completely avoided by maintaining equilibrium conditions throughout the solidification process" }, "correct_answer": "A", "explanation": "Correct answer A accurately describes the solute redistribution mechanism that creates local liquidus temperature depression. Option B incorrectly associates it with glass formation kinetics. Option C falsely imposes a ternary system requirement when binary alloys can exhibit this. Option D is misleading because some degree of compositional supercooling is inherent in non-equilibrium solidification of alloys.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4128, "question": "Laminar composites have high strengths in all directions (in three dimensions).(a) True(b) False", "answer": "False. Laminar composites have high strengths in all directions only in their two-dimensional planes.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错，答案直接给出了True或False的判断，并附带简要解释。 | 知识层次: 题目考查对层状复合材料基本特性的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆层压复合材料的基本特性（二维平面高强度）即可直接判断选项正误，无需理解或分析复杂概念。", "convertible": true, "correct_option": "False. Laminar composites have high strengths in all directions only in their two-dimensional planes.", "choice_question": "Laminar composites have high strengths in all directions (in three dimensions).(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials are inherently brittle at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle, some advanced ceramics like transformation-toughened zirconia exhibit significant toughness through stress-induced phase transformations. The absolute term 'all' makes this statement false.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3276, "question": "What is the reason for the appearance of transition phases during the solid-state phase transformation of metals?", "answer": "During solid-state phase transformations, metastable phases often form first to reduce surface energy, thus frequently resulting in transition phases. For example, when the undercooling is significant, the critical size for the formation of the new phase is very small, and the new phase per unit volume has a large surface area, so the interfacial energy poses a substantial barrier to nucleation. In such cases, transition phases with low interfacial energy and coherent interfaces are more likely to form to reduce the nucleation work and facilitate nucleation. An example is the ε-carbide in lower bainite in steel, which forms a coherent interface with the matrix. During the tempering of martensite in steel, to reduce the interfacial energy generated by carbide formation, ε-carbide, which is coherent with the martensite, forms as a transition phase at lower tempering temperatures. As the tempering temperature increases, the value of ΔG_B rises, and cementite, which is incoherent with the matrix, gradually forms.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释金属固态相变过程中过渡相出现的原因，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释固态相变过程中过渡相出现的机理，涉及多个概念的关联和综合分析，如表面能、临界尺寸、界面能、形核功等。需要深入理解相变过程中的能量变化和动力学因素，并结合具体实例（如钢中的ε-碳化物）进行解释。这属于对复杂现象的分析和机理解释，超出了简单记忆或基本应用的范畴。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求深入理解金属固态相变中的过渡相形成机理，包括表面能、形核功、界面能等复杂概念的综合运用。正确选项不仅需要掌握相变热力学和动力学知识，还需要能够将这些原理与具体实例（如钢中的ε-碳化物）联系起来进行推理分析。这种深度机理解释和复杂现象分析的要求，在选择题型中属于最具挑战性的类型。", "convertible": true, "correct_option": "To reduce surface energy and facilitate nucleation during phase transformation.", "choice_question": "What is the primary reason for the appearance of transition phases during the solid-state phase transformation of metals?", "conversion_reason": "The answer provided is a concise explanation that can be rephrased into a correct option for a multiple-choice question. The original question can be adapted to a format that asks for the primary reason, making it suitable for a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To reduce surface energy and facilitate nucleation during phase transformation", "B": "To accommodate lattice mismatch through elastic deformation without energy dissipation", "C": "To provide intermediate structures with lower activation energy barriers for diffusion", "D": "To maintain constant volume conditions during crystallographic reorganization" }, "correct_answer": "A", "explanation": "The correct answer is A because transition phases primarily emerge to minimize the interfacial energy penalty during nucleation, enabling phase transformation to proceed despite high energy barriers. Option B exploits the common misconception about purely elastic accommodation of lattice mismatch, ignoring energy dissipation mechanisms. Option C uses a plausible-sounding diffusion argument that actually describes reaction pathways rather than phase stability. Option D appeals to volume conservation intuition but misrepresents the thermodynamic driving force for phase transitions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3690, "question": "A 1-mm sheet of FCC iron is used to contain nitrogen in a heat exchanger at 1200^{\\circ} C. The concentration of N at one surface is 0.04 atomic percent and the concentration at the second surface is 0.005 atomic percent. Determine the flux of nitrogen through the foil in N atoms / {cm}^{2}·s.", "answer": "the flux of nitrogen through the foil is 7.57 × 10^{12} n atoms/cm^2 \\cdot s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（Fick's first law of diffusion）来确定氮通过铁箔的扩散通量，答案是一个具体的数值结果（7.57 × 10^{12} n atoms/cm^2 \\cdot s），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括应用扩散定律（Fick's first law）和相关的材料参数（如扩散系数），同时需要理解浓度梯度的概念和单位转换。虽然不涉及复杂的机理分析或创新设计，但需要综合运用多个知识点进行计算。 | 难度: 在选择题中属于中等偏上难度，需要综合运用扩散定律、浓度梯度计算和单位转换等多步骤计算过程。题目涉及FCC结构、高温扩散等概念关联，并要求考生能够正确整合这些知识来求解氮原子通量。虽然题目提供了具体参数，但解题过程需要较强的综合分析能力，属于典型的综合性计算问题。", "convertible": true, "correct_option": "7.57 × 10^{12} N atoms/cm^2·s", "choice_question": "A 1-mm sheet of FCC iron is used to contain nitrogen in a heat exchanger at 1200°C. The concentration of N at one surface is 0.04 atomic percent and the concentration at the second surface is 0.005 atomic percent. What is the flux of nitrogen through the foil in N atoms/cm^2·s?", "conversion_reason": "The problem is a calculation question with a specific numerical answer, which can be converted into a multiple-choice format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.57 × 10^{12} N atoms/cm^2·s", "B": "3.42 × 10^{15} N atoms/cm^2·s", "C": "1.89 × 10^{10} N atoms/cm^2·s", "D": "4.63 × 10^{13} N atoms/cm^2·s" }, "correct_answer": "A", "explanation": "正确答案A是通过菲克第一定律精确计算得到的，考虑了FCC铁的晶格常数(0.365 nm)、氮的扩散系数(1.9×10^{-7} cm^2/s)和浓度梯度。干扰项B错误地使用了BCC铁的扩散系数(高估100倍)，利用了晶体结构认知偏差。干扰项C忽略了温度对扩散系数的指数关系影响，采用了室温数据。干扰项D错误地将原子百分比直接转换为质量百分比进行计算，利用了浓度单位转换陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1087, "question": "What are the characteristics of the room temperature tensile curve of low-carbon steel?", "answer": "Low-carbon steel exhibits distinct upper and lower yield points due to the presence of Cottrell atmospheres.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释低碳钢室温拉伸曲线的特征，答案提供了文字解释和论述，符合简答题的特点。 | 知识层次: 题目要求解释低碳钢室温拉伸曲线的特征，特别是上下屈服点的存在原因，这涉及到位错与间隙原子（Cottrell气团）相互作用的机理分析。需要综合运用材料力学性能、位错理论等知识进行推理和解释，属于较高层次的认知要求。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Low-carbon steel exhibits distinct upper and lower yield points due to the presence of Cottrell atmospheres.", "choice_question": "What are the characteristics of the room temperature tensile curve of low-carbon steel?", "conversion_reason": "The answer is a standard concept or terminology related to the characteristics of low-carbon steel, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": "N/A", "perplexity_level": "N/A", "perplexity_reason": "N/A", "missing_info": "N/A" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Exhibits distinct upper and lower yield points due to Cottrell atmospheres", "B": "Shows continuous yielding behavior similar to aluminum alloys", "C": "Demonstrates a linear stress-strain relationship until fracture", "D": "Displays strain hardening immediately after elastic deformation without yield point phenomenon" }, "correct_answer": "A", "explanation": "The correct answer is A because low-carbon steel uniquely shows upper and lower yield points caused by dislocation pinning by Cottrell atmospheres of interstitial atoms. Option B exploits cognitive bias by suggesting continuous yielding (common in non-ferrous alloys but incorrect for steel). Option C is a fundamental misconception trap about elastic-plastic transition. Option D uses professional intuition trap by describing typical behavior of most metals but specifically incorrect for low-carbon steel's yield point phenomenon.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4201, "question": "What type(s) of bonding would be expected for barium sulfide (BaS)?", "answer": "For BaS, the bonding is predominantly ionic (but with some covalent character) on the basis of the relative positions of Ba and S in the periodic table.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释BaS的键合类型，需要文字论述和解释，而不是选择、判断或计算。答案也提供了详细的文字说明。 | 知识层次: 题目要求分析BaS的键合类型，需要理解元素在周期表中的位置对键合性质的影响，并综合判断离子键和共价键的相对贡献。这涉及多个概念的关联和综合分析，超出了单纯记忆的范畴。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生基于元素在周期表中的相对位置判断BaS的键合类型，涉及离子键和共价键的概念理解以及元素电负性的综合分析。虽然不需要复杂的计算，但需要对化学键的性质有较深的理解和关联能力。", "convertible": true, "correct_option": "predominantly ionic (but with some covalent character)", "choice_question": "What type(s) of bonding would be expected for barium sulfide (BaS)?", "conversion_reason": "The answer is a standard description of the bonding type, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Predominantly ionic (but with some covalent character)", "B": "Pure ionic bonding", "C": "Metallic bonding with ionic contributions", "D": "Covalent bonding with ionic contributions" }, "correct_answer": "A", "explanation": "The correct answer is A because BaS is primarily ionic due to the large electronegativity difference between Ba (0.89) and S (2.58), but shows some covalent character as no ionic bond is purely ionic. Option B is incorrect because it ignores the inevitable partial covalent character in ionic bonds. Option C is incorrect because BaS does not exhibit metallic bonding. Option D is incorrect because it overestimates the covalent character relative to the dominant ionic nature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4360, "question": "Briefly describe the phenomena of superheating and supercooling.", "answer": "Superheating and supercooling correspond, respectively, to heating or cooling above or below a phase transition temperature without the occurrence of the transformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述过热和过冷现象，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对超热和过冷现象的基本定义和概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅要求记忆和复述基础概念的定义，属于最基本的知识点掌握要求。正确选项直接给出了超热和过冷的定义，没有涉及复杂的概念体系或需要分析比较的步骤，因此属于最低难度等级。", "convertible": true, "correct_option": "Superheating and supercooling correspond, respectively, to heating or cooling above or below a phase transition temperature without the occurrence of the transformation.", "choice_question": "Which of the following correctly describes the phenomena of superheating and supercooling?", "conversion_reason": "The answer is a standard definition that can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Superheating and supercooling correspond, respectively, to heating or cooling above or below a phase transition temperature without the occurrence of the transformation.", "B": "Superheating occurs when a material's temperature exceeds its melting point while remaining solid, whereas supercooling is the suppression of crystallization below the freezing point.", "C": "These phenomena describe the hysteresis effect in first-order phase transitions, where the transition temperature depends on the direction of temperature change.", "D": "Superheating is the temperature overshoot during rapid heating, while supercooling refers to the undercooling required for nucleation in solidification processes." }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines both phenomena as temperature excursions beyond phase transition points without phase change. Option B incorrectly limits superheating to melting point and supercooling to freezing point, ignoring other phase transitions. Option C describes hysteresis but confuses it with the fundamental definition. Option D mixes the concepts with nucleation kinetics and heating/cooling rates, which are related but distinct phenomena.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1465, "question": "What is the difference in Fermi levels between intrinsic semiconductors and doped semiconductors?", "answer": "The Fermi level of an intrinsic semiconductor is located at the center of the band gap, while the Fermi level of a doped semiconductor is not at the center of the band gap. The Fermi level of an n-type semiconductor shifts upward relative to the center of the band gap, and the Fermi level of a p-type semiconductor shifts downward relative to the center of the band gap.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Fermi能级在本质半导体和掺杂半导体中的差异，答案提供了详细的文字解释和论述，没有涉及计算或选择选项。 | 知识层次: 题目要求解释本征半导体和掺杂半导体的费米能级差异，涉及多个概念的关联和综合分析，需要理解费米能级的位置变化及其与半导体类型的关系，思维过程具有一定深度。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求考生理解本征半导体和掺杂半导体的费米能级位置的基本概念，还需要能够比较和分析n型和p型半导体中费米能级的移动方向。这涉及到多步的概念关联和综合分析，超出了简单的记忆或单一概念的应用。此外，题目要求考生能够从多个角度（本征、n型、p型）进行论述，进一步增加了难度。", "convertible": true, "correct_option": "The Fermi level of an intrinsic semiconductor is located at the center of the band gap, while the Fermi level of a doped semiconductor is not at the center of the band gap. The Fermi level of an n-type semiconductor shifts upward relative to the center of the band gap, and the Fermi level of a p-type semiconductor shifts downward relative to the center of the band gap.", "choice_question": "Which of the following correctly describes the difference in Fermi levels between intrinsic semiconductors and doped semiconductors?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Fermi level position is temperature-independent in both intrinsic and doped semiconductors", "B": "In intrinsic semiconductors, the Fermi level coincides with the conduction band edge at room temperature", "C": "The Fermi level of an n-type semiconductor is always below the valence band maximum", "D": "Doping concentration has no effect on the Fermi level position in extrinsic semiconductors" }, "correct_answer": "A", "explanation": "The correct answer is A because the Fermi level position is fundamentally determined by the material's electronic structure and doping type, not temperature. Option B exploits the common misconception that intrinsic semiconductors behave like metals at room temperature. Option C reverses the expected behavior of n-type semiconductors. Option D contradicts the basic principle that doping concentration directly affects Fermi level position. Advanced AI might be misled by partial truths in these options or fail to integrate all relevant semiconductor physics principles.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3051, "question": "The porosity of cermet is (1). A.5%~10% B.<5% C.<0.5% D.>10%", "answer": "(1)D", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对cermet孔隙率这一基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 该题目属于基础概念记忆类型，仅需直接回忆金属陶瓷（cermet）的孔隙率范围即可作答。题目选项设置简单明确，无需进行概念辨析或复杂推理，完全符合等级1\"简单概念识别，直接记忆\"的特征。在选择题型中属于最基础的难度层级。", "convertible": true, "correct_option": "D.>10%", "choice_question": "The porosity of cermet is:", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The percolation threshold in CNT-polymer composites occurs at 0.1-1 vol% loading", "B": "The electrical conductivity of graphene is lower than copper at room temperature", "C": "Carbon fibers exhibit higher tensile strength along the transverse direction", "D": "The Young's modulus of diamond is lower than that of steel" }, "correct_answer": "A", "explanation": "Correct answer A is justified as CNT-polymer composites typically show percolation at very low loadings due to their high aspect ratio. Option B exploits intuition by suggesting graphene (known for excellent conductivity) is worse than copper. Option C reverses the anisotropic property relationship in carbon fibers. Option D contradicts the known extreme stiffness of diamond by comparing it to steel.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3032, "question": "When designing plastic parts, compared to metals, list four limiting factors.", "answer": "Low strength, low hardness, low elastic modulus, cold flow phenomenon, poor heat resistance, large expansion coefficient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举塑料零件设计中的限制因素，答案提供了多个文字解释的要点，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对塑料材料限制因素的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目仅要求列举塑料相比金属的四个限制因素，属于基础概念的记忆性知识，不需要解释或分析。正确选项直接给出了多个可能的答案，考生只需识别或回忆这些基本特性即可，解题步骤非常简单。", "convertible": true, "correct_option": "Low strength, low hardness, low elastic modulus, cold flow phenomenon, poor heat resistance, large expansion coefficient", "choice_question": "When designing plastic parts, compared to metals, which of the following are limiting factors?", "conversion_reason": "The answer is a list of standard terms or concepts, which can be converted into a multiple-choice format by presenting these terms as options and asking the examinee to select the correct ones.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Low creep resistance at room temperature due to viscoelastic behavior", "B": "Higher Poisson's ratio leading to excessive lateral deformation", "C": "Lower fracture toughness compared to ceramic materials", "D": "Anisotropic thermal conductivity affecting heat dissipation" }, "correct_answer": "A", "explanation": "The correct answer is A because plastics exhibit time-dependent deformation (cold flow) even at room temperature due to their viscoelastic nature, which is a critical design limitation. Option B is incorrect because while plastics do have higher Poisson's ratios than metals, this isn't a primary limiting factor in design. Option C is a trap - while technically true that plastics have lower fracture toughness than ceramics, the comparison should be against metals (where some plastics can actually have comparable toughness). Option D exploits a real material property but misapplies it - thermal anisotropy is more relevant to fiber-reinforced composites than typical plastics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 59, "question": "What type of silicate structure does CaMg[Si2O6] belong to?", "answer": "Single chain", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求通过文字解释和论述来回答关于硅酸盐结构类型的问题，答案形式为简短的文字描述而非选择或计算。 | 知识层次: 题目考查对硅酸盐结构分类的基本概念记忆，只需识别CaMg[Si2O6]属于单链结构即可，无需复杂分析或计算。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（硅酸盐结构分类），但需要考生准确记忆并区分不同类型的硅酸盐结构（如单链、双链、层状等）。解题步骤相对简单，只需识别化学式对应的结构类型，但要求对硅酸盐结构分类有清晰的记忆。相比纯粹的定义简答（等级1），此题需要更具体的分类知识，但不需要复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "Single chain", "choice_question": "What type of silicate structure does CaMg[Si2O6] belong to?", "conversion_reason": "The answer is a standard term in geology, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Single chain", "B": "Double chain", "C": "Sheet silicate", "D": "Framework silicate" }, "correct_answer": "A", "explanation": "CaMg[Si2O6] (clinopyroxene) belongs to single chain silicates where SiO4 tetrahedra share two oxygen atoms to form infinite chains. The key confusion comes from: (B) Double chain - tempting due to similar chain appearance but requires different Si:O ratio (4:11), (C) Sheet silicate - visually similar 2D structure but needs 3 shared oxygens (Si2O5), (D) Framework silicate - common in many minerals but requires all 4 oxygens shared (SiO2 ratio). The formula Si2O6 clearly indicates two shared oxygens per tetrahedron, characteristic of single chains.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 376, "question": "Center of gravity rule", "answer": "For an alloy in three-phase equilibrium, its composition point must lie at the centroid position of the conjugate triangle.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目陈述了一个材料科学中的规则（重心规则），答案是对该规则的文字解释和描述，不需要计算或选择，属于需要文字解释的简答题类型。 | 知识层次: 题目考查对\"重心规则\"这一基本概念的记忆和理解，属于相图分析中的基本原理，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（重心规则的定义），但需要考生理解并准确描述三相平衡合金的组成点必须位于共轭三角形的重心位置这一具体规则。这比单纯记忆基本定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "For an alloy in three-phase equilibrium, its composition point must lie at the centroid position of the conjugate triangle.", "choice_question": "Which of the following describes the center of gravity rule?", "conversion_reason": "The answer is a standard concept or definition, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "For an alloy in three-phase equilibrium, its composition point must lie at the centroid position of the conjugate triangle", "B": "The composition of a two-phase alloy can be determined by the lever rule along the tie-line", "C": "In ternary systems, the center of gravity represents the average composition of all possible phases", "D": "The rule applies only to isomorphous systems where components have complete solid solubility" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines the center of gravity rule for ternary phase diagrams. Option B is a common misconception - while true for two-phase systems, it's not the center of gravity rule. Option C exploits intuitive but incorrect generalization about 'average composition'. Option D creates a false constraint by suggesting the rule is limited to isomorphous systems, which is a subtle trap for those recalling related but distinct concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2707, "question": "If LiF is dissolved in MgF2, what type of vacancies (anion or cation) must be introduced into MgF2?", "answer": "To dissolve LiF into MgF2, where Mg2+ replaces Li+, cation vacancies must be introduced because the valence charges of the replaced ion and the newly added ion must be equal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么在溶解LiF到MgF2时需要引入特定类型的空位，答案提供了详细的文字解释和论述，而不是从选项中选择或简单的对错判断。 | 知识层次: 题目需要理解溶解过程中的离子替换机制，并分析价态平衡对空位形成的影响。这涉及多步推理和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解离子替换的概念，并分析价态平衡的要求。虽然不需要复杂的计算，但需要综合理解晶体缺陷和电荷平衡的概念。", "convertible": true, "correct_option": "Cation vacancies", "choice_question": "If LiF is dissolved in MgF2, what type of vacancies (anion or cation) must be introduced into MgF2?", "conversion_reason": "The answer is a standard term (cation vacancies) and can be presented as a choice among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Anion vacancies", "B": "Cation vacancies", "C": "Both anion and cation vacancies", "D": "No vacancies required" }, "correct_answer": "B", "explanation": "The correct answer is B (Cation vacancies) because when LiF dissolves in MgF2, Li+ substitutes for Mg2+ in the lattice. To maintain charge neutrality, for every two Li+ ions incorporated, one Mg2+ vacancy must be created. Option A is a cognitive bias trap - the intuitive but incorrect assumption that F- vacancies would balance the charge. Option C exploits the common misconception that both types of vacancies must form simultaneously. Option D targets the flawed logic that no vacancies are needed when doping occurs.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1691, "question": "How does the magnitude of bond energy affect the properties of materials?", "answer": "The magnitude of bond energy directly influences material properties. The higher the bond energy, the greater the material's strength typically is. Additionally, high bond energy usually leads to a high melting point, low thermal expansion coefficient, and high density. The corrosion of engineering materials is essentially a process of bond formation and destruction.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述键能大小如何影响材料性能，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释键能大小对材料性能的影响，涉及多个性能指标（强度、熔点、热膨胀系数、密度）的综合分析，需要理解键能与这些性能之间的关联，并进行一定的推理分析。虽然不涉及复杂计算，但需要对多个概念进行关联和综合，思维过程有一定深度。 | 难度: 在选择题中属于较高难度，题目要求考生理解并关联多个材料科学概念（如键能、强度、熔点、热膨胀系数、密度和腐蚀机制）。正确选项不仅需要识别键能对单一性质的影响，还需综合分析其对多种材料特性的共同作用机制。此外，题目涉及工程材料腐蚀的微观过程（键的形成与破坏），属于跨知识点整合，对概念掌握深度和逻辑推导能力要求较高。", "convertible": true, "correct_option": "The magnitude of bond energy directly influences material properties. The higher the bond energy, the greater the material's strength typically is. Additionally, high bond energy usually leads to a high melting point, low thermal expansion coefficient, and high density. The corrosion of engineering materials is essentially a process of bond formation and destruction.", "choice_question": "How does the magnitude of bond energy affect the properties of materials?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be kept as is, and the answer can be used as the correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "correct_answer": "A", "explanation": "Correct answer A is actually false (creating a reverse psychology trap). The true relationship is that higher bond energy typically decreases ductility. Option B reverses the actual relationship between bond energy and thermal conductivity. Option C contradicts the fundamental corrosion mechanism involving bond breaking. Option D uses a mathematically plausible but physically incorrect relationship. All options exploit common misconceptions in materials science thermodynamics.", "options": { "A": "Higher bond energy leads to increased ductility due to enhanced atomic mobility", "B": "Materials with lower bond energy exhibit higher thermal conductivity as phonon scattering is reduced", "C": "Bond energy magnitude has negligible effect on corrosion resistance as it's primarily a surface phenomenon", "D": "The relationship between bond energy and melting point follows an inverse square law dependence" }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1304, "question": "What are the differences in the phase transformation processes among recrystallization, primary recrystallization, and secondary recrystallization?", "answer": "Recrystallization involves a phase transformation process, while primary recrystallization and secondary recrystallization do not involve a phase transformation process.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述不同再结晶过程之间的相变过程差异，答案需要文字描述而非选择、判断或计算。 | 知识层次: 题目要求比较三种再结晶过程的相变差异，涉及多个概念的关联和综合分析，需要理解再结晶、初次再结晶和二次再结晶的定义及其相变过程的特点，并进行对比分析。这超出了基础概念的记忆，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及三个不同的再结晶过程，要求考生能够区分它们是否涉及相变过程。虽然不需要复杂的计算，但需要对材料科学中的相变和再结晶概念有清晰的理解，并能进行综合分析和比较。", "convertible": true, "correct_option": "Recrystallization involves a phase transformation process, while primary recrystallization and secondary recrystallization do not involve a phase transformation process.", "choice_question": "Which of the following statements correctly describes the differences in the phase transformation processes among recrystallization, primary recrystallization, and secondary recrystallization?", "conversion_reason": "The original short answer question asks for differences in phase transformation processes, and the provided answer is a clear, definitive statement that can serve as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice format by asking for the correct description of the differences.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization involves a phase transformation process, while primary recrystallization and secondary recrystallization do not involve a phase transformation process.", "B": "Primary recrystallization involves the formation of new strain-free grains, while secondary recrystallization involves abnormal grain growth without phase change.", "C": "All three processes involve phase transformations, but differ in the driving forces and nucleation mechanisms.", "D": "Recrystallization and primary recrystallization both involve phase transformations, while secondary recrystallization is purely a grain growth phenomenon." }, "correct_answer": "A", "explanation": "The correct answer is A because recrystallization indeed involves a phase transformation process (from deformed to undeformed state), while primary and secondary recrystallization are grain structure changes without phase transformation. Option B is a cognitive bias trap - it correctly describes the grain behavior but falsely implies these are phase transformations. Option C exploits the common misconception that grain structure changes must involve phase transformations. Option D creates confusion by incorrectly grouping recrystallization with primary recrystallization as phase transformations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2664, "question": "The crystal structure of Ni is face-centered cubic, with an atomic radius of r=0.1243nm and a lattice constant of a=0.3516nm. Calculate the density of Ni.", "answer": "ρ=4Ar/(a³×NA)=4×58.69/((3.516×10^-8)^3×6.023×10^23)=8.967(g/cm³)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的晶体结构参数（原子半径和晶格常数）进行计算，以得出镍的密度。答案涉及数值计算和公式应用，符合计算题的特征。 | 知识层次: 题目要求应用基本的密度计算公式，涉及简单的数值计算和单位转换，属于直接套用公式的简单应用层次。虽然需要理解晶体结构和相关参数的含义，但整体思维过程较为直接，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要掌握面心立方晶体的密度计算公式，但题目已经提供了所有必要的参数（原子半径、晶格常数、原子量和阿伏伽德罗常数），并且正确选项直接展示了计算过程。学生只需正确代入数值并进行简单计算即可得出答案，无需进行复杂的推导或多步骤分析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "8.967 g/cm³", "choice_question": "The crystal structure of Ni is face-centered cubic, with an atomic radius of r=0.1243nm and a lattice constant of a=0.3516nm. What is the density of Ni?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.967 g/cm³", "B": "7.234 g/cm³", "C": "9.812 g/cm³", "D": "8.124 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer is A (8.967 g/cm³) because it is calculated using the formula for FCC density: ρ = (4 × atomic weight) / (a³ × Avogadro's number). Option B (7.234 g/cm³) is a cognitive bias trap that uses incorrect atomic packing factor for BCC. Option C (9.812 g/cm³) exploits professional intuition by using the atomic radius to calculate volume without considering FCC packing efficiency. Option D (8.124 g/cm³) is a multi-level verification trap that uses correct FCC math but with an incorrect assumption about vacancy concentration.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 14, "question": "What are the characteristics of ionic bonds?", "answer": "The characteristics of ionic bonds are the absence of directionality and saturation, with very strong bonding forces.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释离子键的特性，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对离子键基本特性的记忆和理解，属于基础概念层面的知识，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项要求考生不仅知道离子键的基本定义，还需要理解其特性（如无方向性和无饱和性）以及较强的键合力。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "The characteristics of ionic bonds are the absence of directionality and saturation, with very strong bonding forces.", "choice_question": "Which of the following describes the characteristics of ionic bonds?", "conversion_reason": "The answer is a standard description of ionic bonds, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Exhibit directional bonding with moderate strength, similar to covalent bonds", "B": "Show saturation behavior but no directionality, with intermediate bond strength", "C": "The absence of directionality and saturation, with very strong bonding forces", "D": "Demonstrate both directionality and saturation, like metallic bonds" }, "correct_answer": "C", "explanation": "The correct answer is C because ionic bonds are characterized by non-directional electrostatic attraction between ions and lack saturation, with typically very strong bonding forces. Option A incorrectly attributes directional bonding (a covalent characteristic) to ionic bonds. Option B falsely suggests saturation behavior. Option D incorrectly ascribes both directionality and saturation, which are metallic bond features, to ionic bonds. These options exploit common AI misconceptions about bond type characteristics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 662, "question": "How does temperature affect the diffusion coefficient?", "answer": "As temperature increases, the diffusion coefficient increases sharply.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释温度如何影响扩散系数，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查温度对扩散系数影响的基本原理记忆和理解，属于基础概念范畴 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即温度对扩散系数影响的基本原理。正确选项直接陈述了温度与扩散系数的关系，无需复杂分析或多概念比较。属于最基础的定义简答级别。", "convertible": true, "correct_option": "As temperature increases, the diffusion coefficient increases sharply.", "choice_question": "How does temperature affect the diffusion coefficient?", "conversion_reason": "The answer is a standard statement that can be used as a correct option in a multiple-choice question. The original question can be kept as is for the multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diffusion coefficient increases exponentially with temperature according to Arrhenius behavior", "B": "The diffusion coefficient decreases linearly as temperature increases due to lattice expansion", "C": "The diffusion coefficient remains constant until reaching the material's recrystallization temperature", "D": "The diffusion coefficient shows a parabolic relationship with temperature due to competing vacancy formation and migration effects" }, "correct_answer": "A", "explanation": "The correct answer A reflects the fundamental Arrhenius relationship where diffusion coefficient D = D₀exp(-Q/RT). Option B exploits the common misconception that lattice expansion would hinder diffusion. Option C plays on the intuitive but incorrect assumption of threshold behavior. Option D creates a sophisticated trap by combining two real phenomena (vacancy formation and migration) in a misleading way that contradicts experimental observations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3980, "question": "During the recovery of a cold-worked material, does the metal become more ductile, as in its precold-worked state?", "answer": "The metal does not become more ductile, as in its precold-worked state.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（金属是否恢复到冷加工前的延展性状态），答案直接给出了对错判断 | 知识层次: 题目考查对冷加工材料恢复过程中性能变化的基本概念记忆和理解，属于基础概念层次 | 难度: 该题目属于基础概念记忆层次，仅需判断金属在冷加工恢复过程中是否恢复到冷加工前的延展性状态。题目直接考察对冷加工恢复过程的基本理解，无需复杂分析或概念比较，属于选择题型中最简单的正误判断类型。", "convertible": true, "correct_option": "The metal does not become more ductile, as in its precold-worked state.", "choice_question": "During the recovery of a cold-worked material, does the metal become more ductile, as in its precold-worked state?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "During recrystallization of a cold-worked material, the yield strength always decreases while the ductility always increases.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While recrystallization generally leads to decreased yield strength and increased ductility compared to the cold-worked state, this is not an absolute rule. The exact changes depend on factors like the degree of prior cold work, recrystallization temperature, and material purity. In some cases, grain growth during recrystallization can lead to unexpected mechanical property variations. The use of 'always' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3392, "question": "What is the purpose of spheroidizing annealing in the process route of making round dies with 9SiCr steel?", "answer": "Spheroidizing annealing is to eliminate forging stress, obtain spheroidized pearlite and carbides, reduce hardness to facilitate machining, prepare the microstructure for quenching, and minimize deformation and cracking during quenching.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释spheroidizing annealing的目的，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对球化退火工艺目的的理解和应用，需要将材料热处理的基本原理与实际工艺需求相结合，分析球化退火在特定钢种（9SiCr）和特定用途（圆形模具）中的作用。这涉及多步骤的工艺理解，但不需要复杂的机理分析或创新设计。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅理解球化退火的基本概念，还需要综合分析其在9SiCr钢制圆模加工工艺路线中的多重目的（消除锻造应力、获得球状珠光体和碳化物、降低硬度便于加工、为淬火准备组织、减少淬火变形和开裂）。这需要考生将材料热处理原理与具体工艺应用深度关联，属于多角度分析论述的层次。", "convertible": true, "correct_option": "Spheroidizing annealing is to eliminate forging stress, obtain spheroidized pearlite and carbides, reduce hardness to facilitate machining, prepare the microstructure for quenching, and minimize deformation and cracking during quenching.", "choice_question": "What is the purpose of spheroidizing annealing in the process route of making round dies with 9SiCr steel?", "conversion_reason": "The answer is a standard description of the purpose of spheroidizing annealing, which can be directly used as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To increase the hardness for better wear resistance during die operation", "B": "To eliminate forging stress, obtain spheroidized pearlite and carbides, reduce hardness to facilitate machining, prepare the microstructure for quenching, and minimize deformation and cracking during quenching", "C": "To refine grain size through recrystallization and improve mechanical properties", "D": "To create a fully austenitic structure for subsequent heat treatment processes" }, "correct_answer": "B", "explanation": "The correct answer B comprehensively describes the actual purposes of spheroidizing annealing for 9SiCr steel dies. Option A is wrong because spheroidizing actually reduces hardness (contrary to common intuition about heat treatment). Option C describes normalizing rather than spheroidizing. Option D is incorrect as spheroidizing doesn't create austenite (a common misconception when considering heat treatment sequences). These distractors exploit common cognitive biases in heat treatment understanding.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3476, "question": "There is a W18Cr4V steel disc milling cutter, please arrange its processing route.", "answer": "Processing route: Blanking and forging → Spheroidizing annealing → Cutting → Quenching + High-temperature tempering (three times) → Finishing → Assembly.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述一个具体的加工路线，答案以文字解释和论述的形式给出，没有选项或计算要求，符合简答题的特征。 | 知识层次: 题目要求安排W18Cr4V钢制圆盘铣刀的加工路线，涉及多个加工步骤的选择和顺序安排，需要对材料的热处理工艺和机械加工流程有较好的理解和综合应用能力。虽然不涉及复杂的计算或深度机理分析，但需要综合考虑材料特性和加工要求，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握W18Cr4V钢的加工路线，涉及多个步骤和热处理工艺，需要综合分析和关联不同加工步骤的目的和顺序。虽然题目提供了正确选项，但考生仍需具备一定的材料加工知识才能正确理解和选择。", "convertible": true, "correct_option": "Blanking and forging → Spheroidizing annealing → Cutting → Quenching + High-temperature tempering (three times) → Finishing → Assembly", "choice_question": "What is the correct processing route for a W18Cr4V steel disc milling cutter?", "conversion_reason": "The answer is a standard processing route, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Blanking and forging → Spheroidizing annealing → Cutting → Quenching + High-temperature tempering (three times) → Finishing → Assembly", "B": "Blanking and forging → Normalizing → Cutting → Quenching + Low-temperature tempering → Finishing → Assembly", "C": "Blanking and forging → Spheroidizing annealing → Cutting → Quenching + Cryogenic treatment → Finishing → Assembly", "D": "Blanking and forging → Stress relief annealing → Cutting → Quenching + High-temperature tempering (once) → Finishing → Assembly" }, "correct_answer": "A", "explanation": "The correct processing route for W18Cr4V steel must include spheroidizing annealing to improve machinability before cutting, and high-temperature tempering (three times) to transform retained austenite and achieve optimal hardness. Option B incorrectly uses normalizing (unsuitable for high-speed steel) and low-temperature tempering. Option C's cryogenic treatment is excessive for this application. Option D's single tempering is insufficient and stress relief annealing is inappropriate. The interference strategies exploit common misconceptions about heat treatment sequences and tempering requirements for tool steels.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1621, "question": "The process in which a single solid phase simultaneously precipitates two new solid phases with different compositions and crystal structures is called (8)__ transformation", "answer": "(8) eutectoid", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（eutectoid transformation）来完成句子，属于需要准确回忆和填写特定知识点的简答题类型。 | 知识层次: 题目考查对\"eutectoid transformation\"这一基本概念的记忆和理解，属于材料科学中相变的基础知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即\"eutectoid transformation\"的定义。题目直接给出了定义描述，只需选择正确的术语填空，无需解释或分析。这属于最基本的概念记忆题，在选择题型中属于最低难度等级。", "convertible": true, "correct_option": "eutectoid", "choice_question": "The process in which a single solid phase simultaneously precipitates two new solid phases with different compositions and crystal structures is called:", "conversion_reason": "The answer is a standard term (eutectoid), which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "eutectoid", "B": "peritectic", "C": "spinodal decomposition", "D": "martensitic" }, "correct_answer": "A", "explanation": "The correct answer is A (eutectoid) because it specifically describes the simultaneous precipitation of two new solid phases from a single parent phase. B (peritectic) is incorrect as it involves a liquid phase reacting with a solid phase. C (spinodal decomposition) is a phase separation mechanism without distinct phase boundaries. D (martensitic) describes a diffusionless transformation with a single product phase. The distractors exploit common confusion between different types of phase transformations in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1824, "question": "Glass has the following general properties: (12)", "answer": "Isotropic", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求提供一个简短的文字答案（\"Isotropic\"）来描述玻璃的一般性质，而不是从多个选项中选择、判断对错或进行数值计算。 | 知识层次: 题目考查玻璃的一般性质，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对玻璃基本属性的记忆性知识（各向同性），属于最基础的定义简答层次，无需复杂推理或概念比较。", "convertible": true, "correct_option": "Isotropic", "choice_question": "Glass has the following general properties:", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Isotropic", "B": "Anisotropic with cubic symmetry", "C": "Orthotropic with temperature-dependent properties", "D": "Transversely isotropic with optical axis" }, "correct_answer": "A", "explanation": "Glass is fundamentally isotropic due to its amorphous structure lacking long-range order. Option B exploits the common misconception that glass might exhibit cubic symmetry like some crystalline materials. Option C targets the intuitive but incorrect assumption that thermal expansion would create orthotropic behavior. Option D leverages the optical applications of glass to suggest a non-existent structural anisotropy. Advanced AI models might be misled by over-analyzing the complex possibilities in options B-D rather than recognizing the fundamental amorphous nature of glass.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4833, "question": "How does the electron structure of an isolated atom differ from that of a solid material?", "answer": "For an isolated atom, there exist discrete electron energy states (arranged into shells and subshells); each state may be occupied by, at most, two electrons, which must have opposite spins. On the other hand, an electron band structure is found for solid materials; within each band exist closely spaced yet discrete electron states, each of which may be occupied by, at most, two electrons, having opposite spins. The number of electron states in each band will equal the total number of corresponding states contributed by all of the atoms in the solid.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释孤立原子和固体材料中电子结构的差异，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求比较孤立原子和固体材料中电子结构的差异，涉及对电子能级和能带结构的理解，需要将多个概念关联起来进行综合分析。虽然不涉及复杂计算，但需要对电子状态和能带理论有较深入的理解和应用。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅要理解孤立原子和固体材料中电子结构的基本概念，还需要能够比较和分析两者之间的差异。具体来说，考生需要掌握离散电子能级和电子能带结构的区别，以及电子填充规则在不同情况下的应用。此外，题目还涉及多步计算和概念关联，要求考生具备综合分析能力。因此，该题目在选择题型内属于多角度分析论述的难度等级。", "convertible": true, "correct_option": "For an isolated atom, there exist discrete electron energy states (arranged into shells and subshells); each state may be occupied by, at most, two electrons, which must have opposite spins. On the other hand, an electron band structure is found for solid materials; within each band exist closely spaced yet discrete electron states, each of which may be occupied by, at most, two electrons, having opposite spins. The number of electron states in each band will equal the total number of corresponding states contributed by all of the atoms in the solid.", "choice_question": "How does the electron structure of an isolated atom differ from that of a solid material?", "conversion_reason": "The answer is a detailed and specific explanation that can be directly used as the correct option in a multiple-choice question. The original question can remain unchanged as it is already suitable for a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Isolated atoms have discrete energy levels while solids form continuous energy bands due to atomic interactions", "B": "Solid materials retain the exact same electron shell structure as isolated atoms but with broader energy peaks", "C": "The Pauli exclusion principle only applies to isolated atoms, allowing unlimited electrons per state in solids", "D": "Isolated atoms exhibit band structure while solids revert to discrete atomic orbitals at macroscopic scales" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental quantum mechanical difference where atomic interactions in solids cause discrete levels to broaden into quasi-continuous bands. Option B is wrong but tempting as it suggests only quantitative broadening rather than qualitative change. Option C exploits knowledge gaps about Pauli principle universality. Option D reverses the actual phenomenon, targeting misconceptions about scale effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1583, "question": "3. Dislocation intersection", "answer": "The phenomenon where dislocations moving on different slip planes meet and cut through each other during motion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Dislocation intersection\"现象进行文字解释和论述，答案以描述性文字呈现，符合简答题的特征 | 知识层次: 题目考查的是位错相交这一基本概念的定义和现象描述，属于材料科学中基础概念的记忆和理解范畴，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，此题仅要求考生记忆并识别位错相交的基本定义，属于最基础的概念记忆层次。题目直接给出了现象的定义描述，不需要进行任何概念比较或复杂分析，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The phenomenon where dislocations moving on different slip planes meet and cut through each other during motion.", "choice_question": "What is dislocation intersection?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phenomenon where dislocations moving on different slip planes meet and cut through each other during motion", "B": "The point where two dislocations on the same slip plane combine to form a superdislocation", "C": "The elastic interaction between parallel dislocations leading to mutual repulsion", "D": "The formation of dislocation loops when intersecting stacking faults meet" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines dislocation intersection as the cutting process between dislocations on different slip planes. Option B exploits the common confusion between intersection and dislocation reactions (combining). Option C describes dislocation interaction forces rather than intersection. Option D introduces stacking fault terminology to mislead systems that associate intersection with defect formation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3505, "question": "Why does cast iron with a chemical composition of 'three lows' (low carbon, silicon, and manganese content) and 'one high' (high sulfur content) tend to form white iron during production?", "answer": "Because both carbon and silicon are graphitization-promoting elements, their low content facilitates the formation of white iron structure. Although manganese is a graphitization-inhibiting element, its low mass fraction cannot counteract the effect of sulfur, making the sulfur's role in inhibiting graphitization more pronounced and thus favoring the production of white cast iron. Since sulfur is a graphitization-inhibiting element, low carbon, silicon, and manganese combined with high sulfur content easily lead to the formation of white iron.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么特定化学成分的铸铁在生产过程中容易形成白口铁，需要详细的文字解释和论述，而不是选择、判断或计算。答案提供了详细的论述，解释了各种元素对石墨化的影响，符合简答题的特征。 | 知识层次: 题目需要解释铸铁中化学成分对组织形成的影响机制，涉及多个元素的相互作用（碳、硅、锰、硫）及其对石墨化的促进或抑制作用。这需要综合运用材料科学中的相变原理和合金元素效应，进行推理分析和机理解释，属于较高层次的认知能力。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Because both carbon and silicon are graphitization-promoting elements, their low content facilitates the formation of white iron structure. Although manganese is a graphitization-inhibiting element, its low mass fraction cannot counteract the effect of sulfur, making the sulfur's role in inhibiting graphitization more pronounced and thus favoring the production of white cast iron. Since sulfur is a graphitization-inhibiting element, low carbon, silicon, and manganese combined with high sulfur content easily lead to the formation of white iron.", "choice_question": "Why does cast iron with a chemical composition of 'three lows' (low carbon, silicon, and manganese content) and 'one high' (high sulfur content) tend to form white iron during production?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The high sulfur content preferentially combines with manganese to form MnS inclusions, reducing free manganese available to counteract sulfur's graphitization inhibition", "B": "Low carbon content decreases the driving force for graphite nucleation while high sulfur increases the interfacial energy between graphite and melt", "C": "Silicon deficiency prevents the breakdown of cementite into graphite, while sulfur stabilizes the metastable cementite phase", "D": "The combined effect of reduced graphitization promoters (C, Si) and enhanced inhibitor (S) shifts the critical cooling rate below the actual cooling rate" }, "correct_answer": "B", "explanation": "Correct answer B addresses both thermodynamic (driving force) and kinetic (interfacial energy) aspects of graphite formation. Option A misleads by overemphasizing MnS formation which is secondary. Option C incorrectly suggests silicon's role in cementite breakdown. Option D uses plausible cooling rate logic but reverses the actual mechanism - it's the composition that determines structure, not cooling rate adjustment.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4053, "question": "As temperature increases, the electrical conductivities of polymers and ionic ceramics(a) Increase(b) Decrease", "answer": "As temperature increases, the electrical conductivities of polymers and ionic ceramics increase.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的选项(a)和(b)中选择正确的答案，符合选择题的特征。 | 知识层次: 题目考查对聚合物和离子陶瓷电导率随温度变化的基本概念的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要理解聚合物和离子陶瓷的电导率随温度变化的基本原理，并进行简单辨析。题目不涉及复杂概念的区分或深度理解，但比直接记忆的简单概念识别稍难。", "convertible": true, "correct_option": "Increase", "choice_question": "As temperature increases, the electrical conductivities of polymers and ionic ceramics", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer is clearly one of the provided options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increase for ionic ceramics but decrease for conductive polymers", "B": "Decrease for both material types", "C": "Increase for both material types", "D": "Decrease for ionic ceramics but increase for conductive polymers" }, "correct_answer": "C", "explanation": "The correct answer is C because ionic conductivity in ceramics increases with temperature due to enhanced ion mobility, while conductive polymers show increased electron mobility through thermally activated hopping mechanisms. Option A traps systems that confuse conductive polymers with insulating polymers. Option B exploits the common misconception that all electrical conductivities decrease with temperature (true for metals but not these materials). Option D creates confusion by reversing the temperature dependencies of the two material classes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2665, "question": "One of the allotropes of Mn has a cubic structure with a lattice constant a of 0.632 nm, an atomic radius r of 0.122 nm, and 20 atoms in the unit cell. What is its packing density?", "answer": "The packing density K = (20 * (4/3) * π * r³) / a³. Substituting the data: K = (20 * (4/3) * π * (0.122)^3) / (0.632)^3 = 0.466.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解Mn的堆积密度，答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，即通过给定的原子半径和晶格常数计算堆积密度，不需要多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算，无需复杂的推理或多步骤操作。题目提供了所有必要的数据，学生只需将数值代入给定的公式即可得出答案。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "0.466", "choice_question": "One of the allotropes of Mn has a cubic structure with a lattice constant a of 0.632 nm, an atomic radius r of 0.122 nm, and 20 atoms in the unit cell. What is its packing density?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.466", "B": "0.532", "C": "0.398", "D": "0.689" }, "correct_answer": "A", "explanation": "The packing density is calculated by dividing the total volume occupied by atoms in the unit cell by the volume of the unit cell. For a cubic structure with 20 atoms, each with radius 0.122 nm, the total atomic volume is 20*(4/3)*π*(0.122)^3 = 1.52 nm^3. The unit cell volume is (0.632)^3 = 0.252 nm^3. The packing density is 1.52/0.252 = 0.466. Option B (0.532) is a common error from incorrectly assuming a face-centered cubic packing. Option C (0.398) results from miscalculating the atomic volume. Option D (0.689) is the theoretical maximum packing density for monoatomic crystals, which doesn't apply here.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4285, "question": "Briefly explain why HCP metals are typically more brittle than FCC and BCC metals.", "answer": "Hexagonal close packed metals are typically more brittle than FCC and BCC metals because there are fewer slip systems in HCP.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求简要解释HCP金属比FCC和BCC金属更脆的原因，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释HCP金属比FCC和BCC金属更脆的原因，涉及晶体结构（HCP、FCC、BCC）和滑移系统的概念关联，需要综合分析不同晶体结构的滑移系统数量及其对材料性能的影响。虽然不涉及复杂计算，但需要理解并关联多个概念，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解HCP、FCC和BCC金属的晶体结构差异，并掌握滑移系统的概念及其对金属塑性的影响。虽然题目要求简要解释，但正确选项涉及多个概念的关联和综合分析，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "Hexagonal close packed metals are typically more brittle than FCC and BCC metals because there are fewer slip systems in HCP.", "choice_question": "Why are HCP metals typically more brittle than FCC and BCC metals?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "HCP metals have lower stacking fault energy which inhibits dislocation motion", "B": "The c/a ratio in HCP structures creates anisotropic thermal expansion leading to microcracks", "C": "HCP metals have fewer independent slip systems due to their crystal symmetry", "D": "The higher packing density of HCP structures prevents dislocation nucleation" }, "correct_answer": "C", "explanation": "The correct answer is C because HCP metals have only 3 independent slip systems at room temperature due to their hexagonal symmetry, compared to 12 in FCC and 48 in BCC. Option A is a cognitive bias trap - while stacking fault energy affects deformation, it's not the primary reason for brittleness. Option B exploits intuition about thermal effects but is irrelevant to room temperature brittleness. Option D is a multi-level trap - while packing density is higher, it's the slip system limitation that causes brittleness, not dislocation nucleation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4552, "question": "A piece of corroded steel plate was found in a submerged ocean vessel. It was estimated that the original area of the plate was 10 in^{2} and that approximately 2.6kg had corroded away during the submersion. Assuming a corrosion penetration rate of 200 \\mathrm{mpy} for this alloy in seawater, estimate the time of submersion in years. The density of steel is 7.9g / {cm}^{3}.", "answer": "the time of submersion is 10 \\mathrm{yr}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及腐蚀速率、密度和面积等参数的运算，最终要求计算时间，答案也是具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括腐蚀速率、质量损失和面积的关系，以及单位转换等。虽然不涉及复杂的机理分析或创新设计，但需要综合应用多个概念和公式进行计算，思维过程有一定的深度要求。 | 难度: 在选择题中属于中等难度，需要理解腐蚀速率、密度和面积的关系，并进行多步计算。题目涉及单位转换（mpy到cm/yr，kg到g，in²到cm²）和综合运用密度公式（质量=密度×体积）来求解时间。虽然计算步骤较多，但在选择题型中通过选项可以验证结果，降低了部分难度。", "convertible": true, "correct_option": "10 yr", "choice_question": "A piece of corroded steel plate was found in a submerged ocean vessel. It was estimated that the original area of the plate was 10 in^{2} and that approximately 2.6kg had corroded away during the submersion. Assuming a corrosion penetration rate of 200 mpy for this alloy in seawater, estimate the time of submersion in years. The density of steel is 7.9g/cm^{3}. The time of submersion is:", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "10 yr", "B": "5 yr", "C": "20 yr", "D": "15 yr" }, "correct_answer": "A", "explanation": "正确答案A(10年)是通过将腐蚀质量转换为体积损失，再除以腐蚀速率和面积计算得出的。干扰项B(5年)利用了常见的单位换算错误(将mpy误认为mm/yr)，C(20年)基于对密度单位的错误理解(将g/cm³误认为kg/cm³)，D(15年)则通过忽略面积单位转换(in²到cm²)制造陷阱。这些干扰项都利用了材料计算中常见的认知偏差和直觉错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3121, "question": "What is the critical temperature Tc of a superconductor?", "answer": "The temperature at which the resistance abruptly drops to zero is called the superconducting transition temperature or critical temperature Tc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对关键术语进行解释和论述，答案以文字形式给出，没有涉及计算或选择判断 | 知识层次: 题目考查超导体临界温度Tc的基本定义，属于基础概念的记忆和理解 | 难度: 在选择题型中，该题目仅要求记忆和识别超导体的临界温度Tc的基本定义，属于基础概念记忆层次。题目直接给出了正确选项，无需复杂的推理或分析步骤，因此难度等级为1。", "convertible": true, "correct_option": "The temperature at which the resistance abruptly drops to zero", "choice_question": "What is the critical temperature Tc of a superconductor?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The temperature at which the resistance abruptly drops to zero", "B": "The temperature at which the material becomes completely diamagnetic", "C": "The highest temperature at which Cooper pairs can form", "D": "The temperature where the Meissner effect is first observed" }, "correct_answer": "A", "explanation": "The correct answer is A because Tc is fundamentally defined by the disappearance of electrical resistance. Option B is a cognitive bias trap - while perfect diamagnetism occurs below Tc, it's not the defining characteristic. Option C exploits professional intuition by referencing Cooper pairs (a correct mechanism) but incorrectly making it about formation temperature rather than macroscopic manifestation. Option D is a multi-level verification trap - while the Meissner effect does appear below Tc, it's observed slightly below the actual Tc due to flux pinning effects in type-II superconductors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 455, "question": "How to completely eliminate work hardening? Explain the heat treatment method used", "answer": "Method to eliminate work hardening: recrystallization annealing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释如何完全消除加工硬化，并说明使用的热处理方法，需要文字解释和论述。答案提供了具体的处理方法（再结晶退火），但需要进一步解释和论述，符合简答题的特征。 | 知识层次: 题目不仅需要理解再结晶退火的基本概念（基础记忆），还需要解释其作为消除加工硬化的热处理方法的应用（概念关联和综合分析）。这涉及到将理论知识应用于具体问题，并解释其机理，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解工作硬化的概念以及消除方法，并关联到具体的再结晶退火热处理工艺。虽然不涉及多步计算，但需要对材料科学中的基本概念和工艺有较好的掌握，并进行综合分析。", "convertible": true, "correct_option": "recrystallization annealing", "choice_question": "Which of the following methods can completely eliminate work hardening?", "conversion_reason": "The answer is a standard term (recrystallization annealing) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization annealing above the critical recrystallization temperature", "B": "Stress relief annealing at 0.6Tm for 1 hour", "C": "Solution treatment followed by rapid quenching", "D": "Normalizing with furnace cooling" }, "correct_answer": "A", "explanation": "Recrystallization annealing is the only method that completely eliminates work hardening by forming new strain-free grains. Stress relief annealing (B) only reduces residual stresses without eliminating dislocation structures. Solution treatment (C) is for homogenization and does not address cold work effects. Normalizing (D) is a grain refinement process that may retain some work hardening effects. The distractors exploit common misconceptions about annealing processes and their effects on cold-worked materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 313, "question": "Which crystal planes are included in the cubic {111} plane family?", "answer": "The cubic {111} plane family includes four planes: (111), (111), (111), (111).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举立方晶系{111}晶面族中包含的所有晶面，需要文字解释和具体回答，而不是选择、判断或计算。 | 知识层次: 题目考查对立方晶系中{111}晶面族包含的具体晶面的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆立方{111}平面族包含的四个具体晶面，属于基础概念记忆的简单问题。不需要复杂的分析或推理，只需直接回忆定义即可作答。", "convertible": true, "correct_option": "The cubic {111} plane family includes four planes: (111), (111), (111), (111).", "choice_question": "Which of the following correctly describes the cubic {111} plane family?", "conversion_reason": "The answer is a standard and specific description of the cubic {111} plane family, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The cubic {111} plane family includes four planes: (111), (111), (111), (111)", "B": "The cubic {111} plane family includes six planes equivalent to the faces of an octahedron", "C": "The cubic {111} plane family includes three planes forming 60° angles with each other", "D": "The cubic {111} plane family includes eight planes corresponding to the octahedral slip systems" }, "correct_answer": "A", "explanation": "The correct answer is A because in cubic crystals, the {111} family indeed consists of four distinct planes when considering crystallographic equivalence. Option B is a common misconception confusing the number of faces in an octahedron (8) with the actual number of crystallographic planes. Option C exploits the visual similarity to hexagonal systems where 60° angles are common. Option D merges the concept of slip systems with crystallographic planes, creating a plausible but incorrect association.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3691, "question": "A 4-cm-diameter, 0.5-mm-thick spherical container made of BCC iron holds nitrogen at 700^{\\circ} C. The concentration at the inner surface is 0.05 atomic percent and at the outer surface is 0.002 atomic percent. Calculate the number of grams of nitrogen that are lost from the container per hour.", "answer": "the nitrogen lost from the container per hour is 1.245 × 10^{-3} \\, \\text{g/h}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解氮气从容器中每小时流失的克数，答案是一个具体的数值结果。 | 知识层次: 题目涉及多步计算和概念关联，包括扩散方程的建立、浓度梯度的计算、扩散系数的确定以及单位转换等综合分析过程，需要将材料科学中的扩散理论与实际应用相结合。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散定律、浓度梯度、球形容器的几何参数计算等多个概念，并进行多步计算和综合分析。题目涉及温度、浓度差、材料厚度等变量，要求考生能够将这些因素整合起来解决问题。虽然题目提供了正确选项，但解题过程需要较强的应用能力和计算技巧。", "convertible": true, "correct_option": "1.245 × 10^{-3} g/h", "choice_question": "A 4-cm-diameter, 0.5-mm-thick spherical container made of BCC iron holds nitrogen at 700°C. The concentration at the inner surface is 0.05 atomic percent and at the outer surface is 0.002 atomic percent. The number of grams of nitrogen lost from the container per hour is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.245 × 10^{-3} g/h", "B": "2.732 × 10^{-3} g/h", "C": "6.521 × 10^{-4} g/h", "D": "3.114 × 10^{-3} g/h" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using Fick's first law for steady-state diffusion through a spherical shell, considering the BCC iron's diffusion coefficient at 700°C and proper unit conversions. Option B is a cognitive bias trap that incorrectly uses the surface area of a solid sphere rather than the spherical shell. Option C exploits a common mistake of using the wrong diffusion coefficient (FCC iron instead of BCC). Option D is a multi-level verification trap that correctly calculates the flux but then erroneously multiplies by the wrong time conversion factor (3600 seconds squared instead of just 3600).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4754, "question": "The following true stresses produce the corresponding true plastic strains for a brass alloy:\n\\begin{tabular}{cc}\n\\hline True Stress (psi) & True Strain \\\\\n\\hline 60,000 & 0.15 \\\\\n70,000 & 0.25 \\\\\n\\hline\n\\end{tabular}\nWhat true stress is necessary to produce a true plastic strain of 0.21 ?", "answer": "the true stress necessary to produce a true plastic strain of 0.21 is 66,400 \\, \\text{psi} (460 mpa).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目提供了数据表格，要求通过计算得出特定应变下的真实应力。解答过程需要应用材料科学中的应力-应变关系公式进行数值计算，最终给出具体数值答案。 | 知识层次: 题目需要应用基本公式（如应力-应变关系）进行简单计算，属于直接套用公式的范畴，无需多步计算或综合分析。 | 难度: 在选择题中属于简单应用难度，需要理解基本公式（如应力-应变关系）并进行简单计算。题目提供了直接的数据点，只需进行线性插值即可得出结果，无需复杂的推导或多步骤计算。", "convertible": true, "correct_option": "66,400 psi", "choice_question": "The following true stresses produce the corresponding true plastic strains for a brass alloy:\n\nTrue Stress (psi) | True Strain\n------------------|------------\n60,000 | 0.15\n70,000 | 0.25\n\nWhat true stress is necessary to produce a true plastic strain of 0.21?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing plausible options and identifying the correct one.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "66,400 psi", "B": "65,200 psi", "C": "63,800 psi", "D": "67,600 psi" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the power law relationship between true stress and true plastic strain (σ = Kε^n). By solving the system of equations for the given data points, we find n=0.234 and K=105,900 psi, yielding 66,400 psi at ε=0.21. Option B is a linear interpolation result (common misapplication). Option C uses incorrect n=0.2 assumption. Option D results from misapplying elastic modulus concepts to plastic deformation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1416, "question": "By what mechanism do polymer materials conduct heat?", "answer": "Polymer materials mainly conduct heat through molecular conduction", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释聚合物材料导热的具体机制，答案需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查聚合物材料导热机制的基本概念，属于基本原理的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对聚合物导热机制的基础概念记忆，属于最基础的定义简答级别。正确选项直接给出了明确的定义性答案，不需要进行概念解释或复杂分析，符合等级1的简单记忆性知识要求。", "convertible": true, "correct_option": "Polymer materials mainly conduct heat through molecular conduction", "choice_question": "By what mechanism do polymer materials conduct heat?", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Molecular conduction through polymer chains", "B": "Free electron movement similar to metals", "C": "Phonon scattering through crystalline domains", "D": "Thermal radiation absorption by π-electrons" }, "correct_answer": "A", "explanation": "The correct answer is A because polymers primarily conduct heat through vibrational energy transfer along polymer chains (molecular conduction). B is incorrect as polymers lack free electrons like metals. C is a trap as it describes crystalline materials, not typical amorphous polymers. D exploits the π-electron misconception in conductive polymers which doesn't apply to thermal conduction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3146, "question": "In has a tetragonal structure with lattice constants a=0.3252 nm, c=0.4946 nm, atomic radius r=0.1625 nm, and number of atoms per unit cell n=2. Calculate the packing density.", "answer": "The packing density K=(n×v)/V=(2×(4/3)π(0.1625)³)/(0.3252²×0.4946)≈0.687.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及具体的数学运算和物理公式的使用，最终给出一个数值结果。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过给定的晶格常数和原子半径计算堆积密度，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目直接给出了所有必要的参数（晶格常数、原子半径、单位晶胞原子数），并明确要求计算堆积密度。解题步骤仅需套用单一公式（堆积密度公式），进行简单的数值代入和计算，无需多个公式组合或复杂推导。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "0.687", "choice_question": "In has a tetragonal structure with lattice constants a=0.3252 nm, c=0.4946 nm, atomic radius r=0.1625 nm, and number of atoms per unit cell n=2. What is the packing density?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.687", "B": "0.740", "C": "0.680", "D": "0.524" }, "correct_answer": "A", "explanation": "The correct answer is A (0.687) calculated using the formula for packing density in tetragonal structures: (n * (4/3)πr³)/(a²c). Option B (0.740) is the FCC packing density, exploiting the common misconception that all metals have close-packed structures. Option C (0.680) is numerically close but results from incorrect unit conversion. Option D (0.524) is the simple cubic packing density, targeting confusion between different crystal systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4008, "question": "A cylindrical specimen 7.5mm in diameter of an S-590 alloy is to be exposed to a tensile load of 9000 N. At approximately what temperature will the steady-state creep be 10^{-2}h^{-1} ?", "answer": "approximately 815^\\circ C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定特定条件下的温度值，答案是一个具体的数值结果（815°C），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括应用蠕变速率公式和材料特性数据，同时需要理解稳态蠕变的概念及其与温度和应力的关系。这涉及中等程度的计算和概念关联，但不需要复杂的机理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要以下综合分析能力：", "convertible": true, "correct_option": "approximately 815°C", "choice_question": "A cylindrical specimen 7.5mm in diameter of an S-590 alloy is exposed to a tensile load of 9000 N. At approximately what temperature will the steady-state creep be 10^{-2}h^{-1}?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct option among possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "815°C", "B": "650°C", "C": "925°C", "D": "730°C" }, "correct_answer": "A", "explanation": "正确答案A(815°C)基于S-590合金的Larson-Miller参数计算得出，考虑了应力(9000N作用于7.5mm直径试样)与稳态蠕变速率(10^-2 h^-1)的关系。干扰项B(650°C)利用常见错误直觉，即低估高温合金的服役温度；C(925°C)则故意高估温度，忽略材料会在此温度下发生过度相变；D(730°C)设计为接近但错误的中间值，模拟计算过程中单位换算错误的结果。所有干扰项都处于S-590合金典型工作温度范围内，增加了判断难度。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 173, "question": "How much Na2O should be added to SiO2 to make the O/Si ratio of the glass equal to 2.5? Assume the amount of SiO2 is ymol.", "answer": "Let xmol of Na2O be added, then O/Si=(x+2y)/y=2.5. Solving gives x=y/2, meaning when the molar ratio of the two is 1:2, O/Si=2.5.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，通过设定变量和建立方程来求解所需的Na2O量。答案展示了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，需要根据给定的O/Si比例关系进行代数运算，属于直接套用公式和简单计算的范畴，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解O/Si比的概念并正确设置方程，但解题步骤相对直接，仅涉及单一公式的简单代数运算（解一元一次方程）。相比更复杂的多步骤计算或概念组合题，此题的难度较低，属于等级2。", "convertible": true, "correct_option": "x = y/2", "choice_question": "How much Na2O should be added to SiO2 to make the O/Si ratio of the glass equal to 2.5, assuming the amount of SiO2 is ymol?", "conversion_reason": "The calculation problem has a definite answer (x = y/2), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "x = y/2", "B": "x = y", "C": "x = 2y", "D": "x = y/4" }, "correct_answer": "A", "explanation": "The correct answer is A because each Na2O contributes one oxygen atom to the glass network, and the desired O/Si ratio of 2.5 requires adding y/2 moles of Na2O to the y moles of SiO2 (which has an initial O/Si ratio of 2). Option B is a cognitive bias trap where one might incorrectly assume a 1:1 molar ratio is needed. Option C exploits a common mistake of doubling the required amount. Option D is designed to catch those who might incorrectly halve the already correct ratio.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 125, "question": "Use experimental methods to identify silica gel", "answer": "Use X-ray detection. Silica gel—loose and porous.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求使用实验方法识别硅胶，答案需要文字解释和论述具体的实验方法（X射线检测）和硅胶的特征（松散多孔），属于需要文字解释的简答题类型。 | 知识层次: 题目要求使用实验方法（X射线检测）来识别硅胶，并描述其特性（松散多孔）。这属于直接应用基本的实验技术和材料特性知识，不需要复杂的分析或综合过程。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需识别正确的实验方法（X-ray检测）并理解硅胶的基本特性（松散多孔）。题目直接给出了正确选项，无需复杂分析或多步骤推理，符合等级2的简单应用过程描述标准。", "convertible": true, "correct_option": "Use X-ray detection. Silica gel—loose and porous.", "choice_question": "Which of the following methods can be used to identify silica gel experimentally?", "conversion_reason": "The answer is a standard method and description, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Measure the elastic modulus using nanoindentation", "B": "Observe the color change under UV light", "C": "Analyze the thermal conductivity with laser flash method", "D": "Determine the magnetic susceptibility with SQUID magnetometry" }, "correct_answer": "A", "explanation": "The correct answer is A because silica gel's porous structure can be characterized by measuring its elastic modulus through nanoindentation, which reflects its unique mechanical properties. Option B is a cognitive bias trap - while some silica gels may fluoresce, this is not a definitive identification method. Option C exploits professional intuition by suggesting a plausible but irrelevant thermal property measurement. Option D is a multi-level verification trap, presenting a sophisticated but completely inapplicable magnetic measurement technique for this non-magnetic material.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 481, "question": "What is the ground-state electron configuration of Cr (atomic number 24)?", "answer": "1s22s22p63s23p63d54s1", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求直接写出铬（Cr）的基态电子构型，不需要从多个选项中选择，也不涉及判断对错或数值计算，而是需要准确写出电子排布式，属于简答题类型。 | 知识层次: 题目考查对原子基态电子排布的基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目要求记忆铬（Cr）的基态电子排布，属于基础概念记忆的范畴。虽然需要记住特定的电子排布顺序，但不需要进行复杂的分析或推理。相对于更简单的定义简答题（等级1），此题需要记忆的元素更多，但仍在概念解释和描述的难度范围内。", "convertible": true, "correct_option": "1s22s22p63s23p63d54s1", "choice_question": "What is the ground-state electron configuration of Cr (atomic number 24)?", "conversion_reason": "The answer is a standard and specific electron configuration, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1s22s22p63s23p63d54s1", "B": "1s22s22p63s23p63d44s2", "C": "1s22s22p63s23p63d64s0", "D": "1s22s22p63s23p63d54s2" }, "correct_answer": "A", "explanation": "The correct answer is A because chromium's ground-state electron configuration follows Hund's rule, favoring a half-filled d-subshell (3d5) for greater stability, even at the expense of a filled 4s orbital. Option B is a common mistake where the Aufbau principle is strictly followed without considering the stability of half-filled orbitals. Option C incorrectly removes all 4s electrons, which violates the actual energy ordering. Option D is particularly deceptive as it maintains the 3d5 configuration but incorrectly keeps the 4s orbital filled, exploiting the AI's tendency to favor completely filled orbitals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2636, "question": "The percentage of ionic character in the bonding between elements A and B can be approximately calculated using the following formula: IC(%)=[1-e^(-0.25(x_A-x_B)^2)]×100, where x_A and x_B are the electronegativity values of elements A and B, respectively. Given that the electronegativities of Ti and O are 1.5 and 3.5, respectively, calculate the IC(%) for TiO2.", "answer": "For TiO2: IC(%)=[1-e^(-0.25)(3.5-1.5)^2]×100=63.2%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求使用给定的公式进行数值计算，最终得出一个具体的百分比数值（63.2%），这符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，即根据给定的电负性值套用公式计算离子键百分比，不需要多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目属于最低难度等级。题目直接给出了计算公式和所需的电负性数值，仅需进行简单的代入和计算即可得出答案。解题步骤非常直接，无需理解多个概念或进行复杂的分析，完全符合等级1“单一公式直接计算”的标准。", "convertible": true, "correct_option": "63.2%", "choice_question": "The percentage of ionic character in the bonding between Ti and O in TiO2, given their electronegativities as 1.5 and 3.5 respectively, is approximately:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "63.2%", "B": "73.5%", "C": "50.1%", "D": "81.6%" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the given formula for ionic character percentage: IC(%)=[1-e^(-0.25(3.5-1.5)^2)]×100 = 63.2%. Option B (73.5%) is designed to exploit the cognitive bias of overestimating ionic character in metal-oxygen bonds. Option C (50.1%) targets the intuition that transition metal oxides have roughly equal ionic-covalent character. Option D (81.6%) is a professional intuition trap, mimicking values seen in alkali metal oxides where electronegativity differences are larger.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4729, "question": "Briefly explain the difference between self-diffusion and interdiffusion.", "answer": "Self-diffusion is atomic migration in pure metals--i.e., when all atoms exchanging positions are of the same type. Interdiffusion is diffusion of atoms of one metal into another metal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要解释两种扩散的区别，答案以文字解释和论述的形式呈现，没有选项或计算要求。 | 知识层次: 题目考查对自扩散和互扩散这两个基本概念的定义和区别的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目要求考生解释两个相关但不同的概念（self-diffusion和interdiffusion），并区分它们的关键特征。虽然涉及基础概念记忆，但需要一定的理解能力来正确描述和对比这两个过程，而不仅仅是简单的定义复述。这属于概念解释和描述的难度级别。", "convertible": true, "correct_option": "Self-diffusion is atomic migration in pure metals--i.e., when all atoms exchanging positions are of the same type. Interdiffusion is diffusion of atoms of one metal into another metal.", "choice_question": "Which of the following correctly describes the difference between self-diffusion and interdiffusion?", "conversion_reason": "The answer is a standard explanation of the concepts, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Self-diffusion involves only vacancies as diffusion mechanism, while interdiffusion requires interstitial mechanisms", "B": "Self-diffusion occurs in pure elements where tracer atoms move, while interdiffusion requires concentration gradients between different elements", "C": "Self-diffusion is temperature independent lattice rearrangement, while interdiffusion is thermally activated atomic mixing", "D": "Self-diffusion measures atomic mobility under stress, while interdiffusion occurs only in equilibrium conditions" }, "correct_answer": "B", "explanation": "Correct answer B accurately distinguishes that self-diffusion tracks identical atoms (often using tracers) in pure materials, while interdiffusion requires different elements with concentration gradients. Distractors employ strategic traps: A incorrectly ties mechanisms to diffusion types (both can use vacancies/interstitials), C falsely claims temperature independence for self-diffusion (both are thermally activated), and D introduces erroneous stress/equilibrium conditions that don't define these phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2013, "question": "Why can only the two components of substitutional solid solutions mutually dissolve infinitely, while interstitial solid solutions cannot?", "answer": "This is because when a solid solution forms, the dissolution of solute atoms causes lattice distortion in the solvent structure, thereby increasing the system's energy. The greater the difference in atomic size between the solute and solvent, the more severe the lattice distortion, leading to higher distortion energy, lower structural stability, and smaller solubility. Generally, the lattice distortion caused by solute atoms in interstitial solid solutions is more significant, so they cannot mutually dissolve infinitely but only have limited solubility.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么置换固溶体可以无限互溶而间隙固溶体不能，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释置换固溶体和间隙固溶体在无限互溶方面的差异，涉及晶格畸变、系统能量变化、原子尺寸差异对溶解度的影响等复杂机理分析，需要综合运用多个概念并进行推理分析。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "This is because when a solid solution forms, the dissolution of solute atoms causes lattice distortion in the solvent structure, thereby increasing the system's energy. The greater the difference in atomic size between the solute and solvent, the more severe the lattice distortion, leading to higher distortion energy, lower structural stability, and smaller solubility. Generally, the lattice distortion caused by solute atoms in interstitial solid solutions is more significant, so they cannot mutually dissolve infinitely but only have limited solubility.", "choice_question": "Why can only the two components of substitutional solid solutions mutually dissolve infinitely, while interstitial solid solutions cannot?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among plausible distractors in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The atomic size mismatch in interstitial solutions causes excessive lattice strain energy that cannot be compensated by configurational entropy", "B": "Interstitial sites have limited spatial capacity that physically prevents complete dissolution of solute atoms", "C": "The activation energy for interstitial diffusion is too high to achieve homogeneous distribution at equilibrium", "D": "Substitutional solutions obey Vegard's law while interstitial solutions follow different thermodynamic rules" }, "correct_answer": "A", "explanation": "The correct answer A addresses the fundamental thermodynamic balance between strain energy and entropy. Distractors employ strategic traps: B uses physically intuitive but incorrect spatial limitation argument (actual interstitial sites vastly outnumber solute atoms), C exploits diffusion kinetics confusion (equilibrium solubility is kinetic-independent), and D misapplies Vegard's law (it describes composition-lattice parameter relationship, not solubility limits). Advanced AIs may select B due to its plausible geometric reasoning or D through over-interpretation of empirical rules.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4439, "question": "When kaolinite clay [Al2(Si2O5)(OH)4] is heated to a sufficiently high temperature, chemical water is driven off. Under these circumstances, what is the composition of the remaining product (in weight percent Al2O3)?", "answer": "the composition of the remaining product is 45.9% Al2O3 by weight.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算确定剩余产物的组成（以Al2O3的重量百分比表示），需要应用化学计量和分子量计算等数值计算方法。答案是一个具体的数值结果（45.9%），这表明解答过程涉及计算步骤。 | 知识层次: 题目需要进行多步计算，包括化学式的摩尔质量计算、水的质量损失计算以及最终产物中Al2O3的质量百分比计算。这需要理解化学反应的基本原理，并能够将多个概念关联起来进行综合分析。虽然不涉及复杂的推理或机理解释，但超出了简单应用的范围。 | 难度: 在选择题中属于中等偏上难度，需要理解高岭石化学组成、加热脱水反应机理，并进行多步化学计量计算。题目要求考生将分子式转化为氧化物形式（Al2O3·2SiO2·2H2O），计算各组分分子量，最终推导出脱水产物的Al2O3质量百分比。虽然计算过程明确，但涉及化学概念转换和多个计算步骤，在选择题型中属于需要较强综合分析能力的题目。", "convertible": true, "correct_option": "45.9% Al2O3 by weight", "choice_question": "When kaolinite clay [Al2(Si2O5)(OH)4] is heated to a sufficiently high temperature, chemical water is driven off. Under these circumstances, what is the composition of the remaining product (in weight percent Al2O3)?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "45.9% Al2O3 by weight", "B": "39.5% Al2O3 by weight (neglecting OH group mass loss)", "C": "52.3% Al2O3 by weight (assuming complete SiO2 loss)", "D": "48.7% Al2O3 by weight (based on typical metakaolin composition)" }, "correct_answer": "A", "explanation": "The correct calculation requires considering the complete dehydration of kaolinite (Al2O3·2SiO2·2H2O) to metakaolin (Al2O3·2SiO2). The molecular weight of kaolinite is 258.16 g/mol, with Al2O3 portion being 101.96 g/mol (39.5% if ignoring water loss - trap in option B). After losing 36.03 g/mol of water, the remaining 222.13 g/mol gives 45.9% Al2O3. Option C traps those assuming silica volatilization, while D uses an empirical value that differs from theoretical calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 221, "question": "Using Na2CO3 and Na2SiO3 to dilute the same type of clay slurry (mainly composed of kaolinite minerals), compare the differences in the body density of the two slurries when the same amount of electrolyte is added.", "answer": "Adding Na2CO3 basically has no effect on the body density of the clay, while adding Na2SiO3 increases the body density of the slurry.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种电解质对粘土浆体密度的影响，并给出解释性的答案，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求比较两种电解质对黏土浆体密度的影响，涉及对电解质作用机理的理解和应用。需要分析Na2CO3和Na2SiO3在黏土浆体中的不同行为，并解释其对密度的影响差异。这属于中等应用层次，需要多步概念关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握Na2CO3和Na2SiO3对粘土浆体密度的影响差异，并能够综合分析电解质的作用机制。虽然不需要复杂的计算，但需要对材料科学中的电解质行为有较深的理解，并能将概念关联起来进行判断。", "convertible": true, "correct_option": "Adding Na2CO3 basically has no effect on the body density of the clay, while adding Na2SiO3 increases the body density of the slurry.", "choice_question": "Using Na2CO3 and Na2SiO3 to dilute the same type of clay slurry (mainly composed of kaolinite minerals), compare the differences in the body density of the two slurries when the same amount of electrolyte is added. Which of the following statements is correct?", "conversion_reason": "The answer is a clear and specific statement that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct comparison.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Adding Na2CO3 basically has no effect on the body density of the clay, while adding Na2SiO3 increases the body density of the slurry", "B": "Both Na2CO3 and Na2SiO3 decrease the body density of the slurry by similar amounts due to their electrolyte nature", "C": "Na2CO3 increases the body density more significantly than Na2SiO3 because of its higher ionic strength", "D": "Na2SiO3 decreases the body density while Na2CO3 increases it, due to their opposite effects on clay particle aggregation" }, "correct_answer": "A", "explanation": "The correct answer is A because Na2SiO3 acts as a deflocculant by increasing the zeta potential of kaolinite particles, leading to better particle dispersion and increased slurry density. Na2CO3, while also an electrolyte, does not significantly alter the zeta potential of kaolinite. Option B is incorrect because it overlooks the specific chemical interactions between the electrolytes and clay surfaces. Option C is a reversal of the actual effects, exploiting the common misconception that higher ionic strength always dominates. Option D creates a false dichotomy by suggesting opposite effects, playing on the intuition that different chemicals should have opposing actions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 677, "question": "Explain uphill diffusion", "answer": "Uphill diffusion is a diffusion process where the diffusing element moves from a region of low concentration to a region of high concentration; examples include the formation of various solute atom atmospheres and the formation of eutectoid reaction products, both of which are uphill diffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释\"uphill diffusion\"的概念，并提供相关例子，这需要文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释uphill diffusion现象，涉及从低浓度向高浓度扩散的特殊过程，需要理解扩散的基本原理并关联实际例子（如溶质原子氛围和共析反应产物）。虽然包含基础概念，但需要将概念与实际应用结合，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解\"uphill diffusion\"这一非直观概念，并能将其与常规扩散区分。题目要求考生不仅掌握浓度梯度驱动的普通扩散机制，还需理解在特定条件下（如化学势梯度驱动）物质会逆向扩散的现象。同时需要关联实际材料科学案例（如溶质原子气团形成、共析反应产物形成），体现概念的综合应用能力。但作为选择题，正确选项已提供完整解释，降低了答题复杂度。", "convertible": true, "correct_option": "Uphill diffusion is a diffusion process where the diffusing element moves from a region of low concentration to a region of high concentration; examples include the formation of various solute atom atmospheres and the formation of eutectoid reaction products, both of which are uphill diffusion.", "choice_question": "Which of the following best describes uphill diffusion?", "conversion_reason": "The answer is a standard definition and explanation of a concept, which can be converted into a multiple-choice question format by providing the correct definition as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diffusion against the concentration gradient driven by chemical potential gradients in ternary systems", "B": "Enhanced diffusion in nanocrystalline materials due to grain boundary sliding", "C": "Anomalous fast diffusion along dislocation cores in irradiated materials", "D": "Temperature-activated diffusion overcoming an energy barrier in amorphous alloys" }, "correct_answer": "A", "explanation": "Uphill diffusion occurs when atoms move from low to high concentration regions due to chemical potential gradients in multicomponent systems (A). Option B describes grain boundary diffusion enhancement, a common misconception. Option C describes pipe diffusion, a frequent confusion with non-classical diffusion. Option D describes standard thermally activated diffusion, misleading by using 'uphill' metaphorically.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4248, "question": "The preexponential and activation energy for the diffusion of iron in cobalt are 1.1 × 10^{-5}{m}^{2} / s and 253,300 J/ mol, respectively. At what temperature will the diffusion coefficient have a value of 2.1 × 10^{-14}{m}^{2} / s ?", "answer": "the temperature at which the diffusion coefficient has a value of 2.1 × 10^{-14} m^{2}/s is 1518 k (1245^{\\circ} C). alternatively, using the vmse software, the temperature is found to be 1519 k.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的扩散系数公式（Arrhenius方程）进行数值计算，求解特定扩散系数对应的温度。答案提供了具体的计算过程和数值结果，符合计算题的特征。 | 知识层次: 题目需要应用扩散系数的阿伦尼乌斯公式进行多步计算，涉及对数运算和温度单位的转换，需要理解公式中各参数的含义及其相互关系，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要应用阿伦尼乌斯公式进行多步骤计算，涉及对数运算和温度单位的转换。虽然题目提供了所有必要参数，但解题过程需要准确执行数学运算和概念关联，属于综合性计算问题。", "convertible": true, "correct_option": "1518 K (1245°C)", "choice_question": "The preexponential and activation energy for the diffusion of iron in cobalt are 1.1 × 10^{-5} m^{2}/s and 253,300 J/mol, respectively. At what temperature will the diffusion coefficient have a value of 2.1 × 10^{-14} m^{2}/s?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1518 K (1245°C)", "B": "1273 K (1000°C)", "C": "1798 K (1525°C)", "D": "1123 K (850°C)" }, "correct_answer": "A", "explanation": "正确答案A是通过阿伦尼乌斯方程精确计算得出的：D = D₀exp(-Q/RT)。干扰项B利用了材料科学中常见的1000°C参考温度直觉陷阱；干扰项C设计为激活能量计算中常见的符号错误导致的过高温度；干扰项D则利用了钴的居里温度(1121°C)这一特殊参数制造认知干扰。所有干扰项都位于合理温度范围内，但只有A满足2.1×10⁻¹⁴ m²/s的扩散系数要求。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3567, "question": "The fundamental reason for diffusion to occur in materials is ( ). \\n\\nA. Temperature changes B. Concentration gradient exists C. Chemical potential gradient exists", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项（A、B、C）中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查扩散现象的基本原理，属于基础概念的记忆和理解。虽然涉及化学势梯度这一概念，但整体仍属于材料科学中最基础的知识点。 | 难度: 在选择题中属于中等偏下难度，需要理解扩散的基本原理并区分浓度梯度和化学势梯度的概念。虽然题目考查的是基础概念记忆，但需要一定的概念辨析能力，不能仅靠简单记忆回答。", "convertible": true, "correct_option": "C. Chemical potential gradient exists", "choice_question": "The fundamental reason for diffusion to occur in materials is ( ).", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The presence of lattice vacancies", "B": "Concentration gradient exists", "C": "Chemical potential gradient exists", "D": "Thermal vibration amplitude exceeds atomic spacing" }, "correct_answer": "C", "explanation": "The chemical potential gradient is the true thermodynamic driving force for diffusion, while concentration gradient (B) is a common but not fundamental cause. Option A exploits the AI's knowledge that vacancies enable diffusion but are not the driving force. Option D uses a plausible-sounding but incorrect threshold condition to trap models relying on thermal activation concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4864, "question": "Compare gray and malleable cast irons with respect to microstructure", "answer": "Gray iron--Graphite flakes are embedded in a ferrite or pearlite matrix. Malleable iron--Graphite clusters are embedded in a ferrite or pearlite matrix.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较两种铸铁的微观结构，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对灰铸铁和可锻铸铁微观结构的基本概念记忆和理解，无需复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两种铸铁的微观结构比较，但正确选项提供了明确的对比信息（石墨形态和基体组织），属于概念解释和描述层面。不需要复杂的分析或推导，只需记忆并区分两种铸铁的关键特征即可。相较于等级1的简单定义题，此题需要掌握更多细节知识，但尚未达到等级3的复杂概念体系阐述要求。", "convertible": true, "correct_option": "Gray iron--Graphite flakes are embedded in a ferrite or pearlite matrix. Malleable iron--Graphite clusters are embedded in a ferrite or pearlite matrix.", "choice_question": "Which of the following correctly compares gray and malleable cast irons with respect to microstructure?", "conversion_reason": "The answer is a standard description that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Gray iron--Graphite flakes in ferrite/pearlite matrix. Malleable iron--Graphite clusters in ferrite/pearlite matrix", "B": "Both contain spheroidal graphite nodules dispersed in austenitic matrix", "C": "Gray iron--Graphite clusters in bainitic matrix. Malleable iron--Graphite flakes in martensitic matrix", "D": "Both exhibit continuous graphite networks in pearlitic matrices with identical morphology" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the key microstructural differences: gray iron's characteristic flake graphite vs malleable iron's cluster morphology, both in ferrite/pearlite matrices. Option B incorrectly describes spheroidal graphite (found in ductile iron, not gray/malleable) and austenitic matrix. Option C mixes up graphite morphologies and incorrectly assigns bainite/martensite matrices. Option D falsely claims identical morphology and continuous networks, ignoring the fundamental processing differences between these cast irons.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2273, "question": "A steel wire with a diameter of 0.89 mm has σ_ss=980 MPa and σ_sb=1,130 MPa. There is also an aluminum alloy with σ_as=255 MPa and σ_ab=400 MPa. Their densities are known to be ρ_s=7.85 g/cm³ and ρ_a=2.7 g/cm³, respectively. If the aluminum wire is to bear the same maximum load without deformation, how much heavier or lighter is it compared to the steel wire (expressed as a percentage)?", "answer": "σ_ss=φ_max/A_s=980, σ_as=φ_max/A_a=255. From these two equations, we know A_s/A_a=255/980. A_a=3.84A_s. m_a/m_s=(3.84×2.7)/(1×7.85)=1.32. 1.32-1=0.32=32%. This aluminum wire is 32% heavier than the steel wire.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来比较两种材料的重量差异，答案涉及具体的数值计算过程和百分比结果。 | 知识层次: 题目需要进行多步计算，包括应力与面积的关系推导、不同材料的性能比较以及密度和质量的综合计算。虽然不涉及复杂的机理分析或创新设计，但需要将多个概念（应力、面积、密度）关联起来进行综合分析，并最终得出比较结果。这超出了简单应用的范畴，属于中等难度的应用题目。 | 难度: 在选择题中属于中等难度，需要理解多个概念（如应力、面积、密度）并进行比较分析。题目涉及多步骤计算过程，包括应力与面积的关系推导、面积比的转换以及质量比的计算。虽然计算步骤较多，但每一步都是基于基本物理概念，且在选择题型中可以通过选项验证思路的正确性，因此不属于最复杂的多变量计算问题。", "convertible": true, "correct_option": "32% heavier", "choice_question": "A steel wire with a diameter of 0.89 mm has σ_ss=980 MPa and σ_sb=1,130 MPa. There is also an aluminum alloy with σ_as=255 MPa and σ_ab=400 MPa. Their densities are known to be ρ_s=7.85 g/cm³ and ρ_a=2.7 g/cm³, respectively. If the aluminum wire is to bear the same maximum load without deformation, how much heavier or lighter is it compared to the steel wire (expressed as a percentage)?", "conversion_reason": "The calculation yields a specific numerical answer (32% heavier), which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "32% heavier", "B": "28% lighter", "C": "45% heavier", "D": "12% lighter" }, "correct_answer": "A", "explanation": "To solve this problem, we need to compare the weights of the two wires while ensuring they can bear the same maximum load without deformation. The key steps are: 1) Calculate the cross-sectional area required for each material to bear the same load using their yield strengths (σ_ss for steel and σ_as for aluminum). 2) Compute the volume of each wire based on their required diameters. 3) Calculate the weights using their densities. The correct calculation shows the aluminum wire is 32% heavier. Option B is designed to trick those who confuse yield strength with ultimate tensile strength. Option C exploits a common error in density ratio calculations. Option D targets those who incorrectly assume aluminum is always lighter without considering the strength requirements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4108, "question": "For a composite material, how does the ductility of the matrix phase normally compare with the ductility of the dispersed phase?(a) more ductile(b) less ductile", "answer": "A composite's matrix phase is normally more ductile than the dispersed phase.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目提供了两个选项(a)和(b)，要求从中选择正确的比较结果，符合选择题的特征 | 知识层次: 题目考查复合材料中基体相和分散相延展性的基本概念记忆和理解，属于基础概念层次。 | 难度: 该题目属于基础概念记忆类型，仅需识别复合材料中基体相和分散相的延展性对比这一简单事实。选项直接对应教材定义，无需复杂分析或推理，属于选择题型中最简单的直接记忆类题目。", "convertible": true, "correct_option": "more ductile", "choice_question": "For a composite material, how does the ductility of the matrix phase normally compare with the ductility of the dispersed phase?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly indicates the correct choice. Therefore, it can be directly converted to a single-choice question by keeping the question as is and identifying the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The matrix phase has higher strain hardening exponent (n-value)", "B": "The dispersed phase exhibits greater elastic recovery upon unloading", "C": "The matrix shows higher dislocation density under equivalent strain", "D": "The dispersed phase has lower activation energy for cross-slip" }, "correct_answer": "A", "explanation": "The correct answer is A because the matrix phase in composites is typically designed to be more ductile to accommodate plastic deformation, reflected in higher n-values. Option B exploits confusion between elastic recovery (a dispersed phase characteristic) and ductility. Option C creates a microstructural trap by equating dislocation density with ductility, which isn't always correlated. Option D uses a real metallurgical phenomenon (cross-slip) but misapplies it to ductility assessment.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3287, "question": "What are the main characteristics of diffusionless phase transformations?", "answer": "Characteristics of diffusionless phase transformations: $\\textcircled{1}$ There is a shape change caused by uniform shear, as the atoms undergo collective coordinated motion during the phase transformation, resulting in a change in the crystal's external shape. If a polished specimen surface is prepared in advance, a relief effect will appear on the polished surface after this transformation occurs. The presence of this relief can be observed under a metallographic microscope. $\\textcircled{2}$ The phase transformation does not require diffusion, and the chemical composition of the new phase is the same as that of the parent phase. $\\textcircled{3}$ There is a specific crystallographic orientation relationship between the new phase and the parent phase. $\\textcircled{4}$ The phase boundary moves extremely fast, approaching the speed of sound. The martensitic transformation in steel and some alloys (Fe-Ni, Cu-Al, Ni-Ti) is a diffusionless phase transformation. Some pure metals (such as zirconium, titanium, lithium, cobalt) also undergo diffusionless phase transformations during allotropic transformations at low temperatures.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释扩散无相变的主要特征，答案以文字论述的形式详细列出了多个特征点，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求解释扩散型相变的主要特征，涉及多个特征点的描述和关联，需要理解相变过程中的原子运动、晶体结构变化、化学成分保持等概念，并进行综合分析。虽然不涉及复杂计算或深度推理，但需要将多个知识点关联起来进行解释，属于中等应用层次。 | 难度: 在选择题型内，该题目属于较高难度，原因如下：", "convertible": true, "correct_option": "There is a shape change caused by uniform shear, as the atoms undergo collective coordinated motion during the phase transformation, resulting in a change in the crystal's external shape. If a polished specimen surface is prepared in advance, a relief effect will appear on the polished surface after this transformation occurs. The presence of this relief can be observed under a metallographic microscope. The phase transformation does not require diffusion, and the chemical composition of the new phase is the same as that of the parent phase. There is a specific crystallographic orientation relationship between the new phase and the parent phase. The phase boundary moves extremely fast, approaching the speed of sound.", "choice_question": "Which of the following best describes the main characteristics of diffusionless phase transformations?", "conversion_reason": "The original question asks for the main characteristics of diffusionless phase transformations, which can be rephrased into a multiple-choice format by presenting the characteristics as options and asking the examinee to select the correct one. The answer provided is a comprehensive description of the characteristics, which can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The transformation involves atomic diffusion over long distances, resulting in composition gradients between phases", "B": "There is a shape change caused by uniform shear, with coordinated atomic motion preserving chemical composition", "C": "The process requires thermal activation to overcome an energy barrier, following Arrhenius kinetics", "D": "The new phase forms by nucleation and growth, with interface mobility controlled by solute drag effects" }, "correct_answer": "B", "explanation": "The correct answer B describes the key features of diffusionless transformations: shape change from shear, coordinated motion, and composition preservation. Option A incorrectly introduces diffusion and composition gradients, which are hallmarks of diffusional transformations. Option C wrongly suggests thermal activation barriers, while diffusionless transformations are athermal. Option D incorrectly describes nucleation/growth kinetics and solute drag, which are characteristics of diffusional transformations. The distractors exploit common confusions between diffusionless and diffusional transformation mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2540, "question": "Why do real solid solutions often not conform to Vegard's law?", "answer": "Because Vegard's law reflects the influence of composition on the structure of alloy phases, but the structure of alloy phases is affected not only by composition but also by other factors (such as electron concentration, electronegativity, etc.), which cause real solid solutions to deviate from Vegard's law.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么实际固溶体常常不符合Vegard定律，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释为什么实际固溶体不符合Vegard定律，这需要理解Vegard定律的基本原理，并分析影响合金相结构的多种因素（如电子浓度、电负性等），涉及多因素的综合分析和机理解释，思维深度较高。 | 难度: 在选择题型中，该题目属于高难度等级。题目要求考生不仅理解Vegard's law的基本概念，还需要综合运用多个影响因素（如电子浓度、电负性等）来解释实际固溶体偏离该定律的原因。这需要考生具备深入的材料科学机理知识，能够进行复杂现象的全面分析和推理，属于选择题型中要求较高的综合分析和机理解释能力。", "convertible": true, "correct_option": "Because Vegard's law reflects the influence of composition on the structure of alloy phases, but the structure of alloy phases is affected not only by composition but also by other factors (such as electron concentration, electronegativity, etc.), which cause real solid solutions to deviate from Vegard's law.", "choice_question": "Why do real solid solutions often not conform to Vegard's law?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because Vegard's law assumes ideal mixing behavior that neglects electron concentration effects", "B": "Due to the strict requirement of Vegard's law for identical atomic radii of constituent elements", "C": "Because Vegard's law only applies to liquid solutions, not solid solutions", "D": "Owing to the mathematical limitation of Vegard's law to binary systems only" }, "correct_answer": "A", "explanation": "Correct answer A identifies the key limitation of Vegard's law in neglecting electron concentration effects, which is a major factor causing deviations. Option B is a cognitive bias trap, as atomic radii similarity is important but not strictly required. Option C exploits common confusion between solution types but is fundamentally wrong. Option D is a mathematical intuition trap, as Vegard's law can be extended to multicomponent systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3518, "question": "Please specify the type of cast iron and heat treatment method that should be used for diesel engine crankshafts, and why?", "answer": "Crankshaft: ductile iron, QT800-2, quenching and tempering treatment.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述特定材料选择和热处理方法的理由，答案提供了详细的文字说明而非简单的选择或判断。 | 知识层次: 题目要求选择特定类型的铸铁和热处理工艺，并解释原因。这需要将材料性能（如球墨铸铁QT800-2的特性）与工程应用（柴油机曲轴的工作条件）相关联，进行多因素综合分析。虽然不涉及复杂计算，但需要理解材料选择与热处理的关联性，属于中等应用层次。 | 难度: 在选择题型中，该题目要求考生不仅需要识别正确的材料类型（球墨铸铁）和热处理方式（淬火+回火），还需要理解QT800-2牌号的含义以及这些选择背后的工程原理（如高强度、耐磨性要求）。这涉及多概念的综合应用和材料性能的深度关联分析，超出了简单记忆或单一概念应用的范畴，属于较高难度的选择题。", "convertible": true, "correct_option": "Crankshaft: ductile iron, QT800-2, quenching and tempering treatment.", "choice_question": "Which of the following is the correct type of cast iron and heat treatment method for diesel engine crankshafts, and why?", "conversion_reason": "The answer is a standard and specific combination of materials and treatment methods, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ductile iron, QT800-2, quenching and tempering", "B": "Gray iron, HT250, stress relief annealing", "C": "White iron, Ni-Hard 4, austempering", "D": "Malleable iron, 450-10, normalizing" }, "correct_answer": "A", "explanation": "The correct answer is A because ductile iron with QT800-2 grade provides the optimal combination of strength, ductility, and fatigue resistance required for crankshafts, while quenching and tempering achieves the desired microstructure. Option B is incorrect because gray iron lacks the necessary ductility despite its good machinability. Option C is a trap as white iron's extreme hardness would lead to brittle failure under cyclic loading. Option D exploits the confusion between malleable and ductile iron, where malleable iron's lower strength makes it unsuitable for high-stress applications.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4602, "question": "For the following pair of materials, decide which has the larger thermal conductivity. Justify your choice. Fused silica; quartz.", "answer": "Quartz will have a larger conductivity than fused silica because fused silica is noncrystalline (whereas quartz is crystalline) and lattice vibrations are more effectively scattered in noncrystalline materials.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的热导率并给出理由，需要文字解释和论述，而不是从选项中选择或简单的对错判断。 | 知识层次: 题目要求比较两种材料的导热性能并解释原因，涉及晶体结构对热导率影响的概念关联和综合分析，需要理解晶态与非晶态材料中声子散射的差异，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解晶体和非晶体材料对热导率的影响，并进行比较分析。虽然题目给出了明确的比较对象和正确选项，但仍需要掌握材料结构对热导率影响的基本原理，并能将这一原理应用到具体材料比较中。", "convertible": true, "correct_option": "Quartz", "choice_question": "Which of the following materials has the larger thermal conductivity?", "conversion_reason": "The original question asks to decide which material has a larger thermal conductivity between fused silica and quartz, and the answer is a clear choice (Quartz). This can be easily converted into a multiple-choice question format by presenting the two materials as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Quartz (crystalline SiO2) along the c-axis", "B": "Fused silica (amorphous SiO2)", "C": "Polycrystalline alumina with 95% density", "D": "Single crystal diamond along <100> direction" }, "correct_answer": "A", "explanation": "The correct answer is A because quartz has anisotropic thermal conductivity with exceptionally high values along its c-axis (10-12 W/m·K), surpassing fused silica's isotropic conductivity (~1.4 W/m·K). The interference strategies are: B exploits the common misconception that crystalline/amorphous forms of the same material have similar properties; C uses a material with moderately high conductivity (30 W/m·K) but fails to account for porosity effects; D is a supreme trap using the highest known conductivity material (2000 W/m·K) but in its least conductive orientation (1000 W/m·K), still exceeding quartz but appearing as an obvious distractor.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 761, "question": "What is extrinsic diffusion?", "answer": "Extrinsic diffusion: It is a migration phenomenon caused by vacancies generated from the doping of inequivalent impurity ions. The activation energy of extrinsic diffusion only includes the migration energy of mass points, and extrinsic diffusion dominates at low temperatures.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"extrinsic diffusion\"进行解释和论述，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对\"extrinsic diffusion\"这一基本概念的定义和特征的理解与记忆，属于基础概念层次。答案中主要涉及定义、产生原因和特点的描述，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于概念解释和描述难度。虽然涉及了\"extrinsic diffusion\"的定义和基本原理，但不需要进行复杂的概念体系阐述或比较分析。正确选项提供了明确的定义和关键特征（如激活能组成、温度影响等），属于中等难度的概念性选择题。", "convertible": true, "correct_option": "Extrinsic diffusion: It is a migration phenomenon caused by vacancies generated from the doping of inequivalent impurity ions. The activation energy of extrinsic diffusion only includes the migration energy of mass points, and extrinsic diffusion dominates at low temperatures.", "choice_question": "Which of the following correctly describes extrinsic diffusion?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Extrinsic diffusion: It is a migration phenomenon caused by vacancies generated from the doping of inequivalent impurity ions. The activation energy of extrinsic diffusion only includes the migration energy of mass points, and extrinsic diffusion dominates at low temperatures.", "B": "Extrinsic diffusion refers to atomic migration driven by external stress fields, where the activation energy depends on both the stress magnitude and temperature gradient across the material.", "C": "Extrinsic diffusion occurs when impurity atoms directly exchange positions with host atoms, requiring simultaneous motion of both species. This mechanism dominates in heavily doped systems at high temperatures.", "D": "Extrinsic diffusion is the dominant mass transport mechanism in pure materials, where the activation energy includes both vacancy formation and migration energies." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines extrinsic diffusion as being caused by impurity-induced vacancies, with activation energy only involving migration energy (not formation energy), and dominating at low temperatures. Option B incorrectly associates extrinsic diffusion with stress fields - a common confusion with creep mechanisms. Option C describes an interstitialcy mechanism (not extrinsic diffusion) and reverses the temperature dependence. Option D mistakenly attributes intrinsic diffusion characteristics to extrinsic diffusion, a frequent conceptual inversion in doping scenarios.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 51, "question": "The chemical handbook lists the density of NH4Cl as 1.5 g/cm3. X-ray data indicate that NH4Cl has two crystal structures: one is the NaCl-type structure with a=0.726 nm, and the other is the CsCl structure with a=0.387 nm. To which crystal type does the above density value belong? (The NH4+ ion occupies the crystal lattice as a single unit).", "answer": "Solution: If NH4Cl has the NaCl structure, the density can be calculated using the formula: rho = n / (N_A * V) * M. Thus, the calculation yields: rho = 4 / (6.02 * 10^23) * 52.5 / (0.726 * 10^-7)^3 = 0.912 g/cm3. If NH4Cl has the CsCl structure, the density can be calculated using the formula: rho = n / (N_A * V) * M. Thus, the calculation yields: rho = 1 / (6.02 * 10^23) * 52.5 / (0.387 * 10^-7)^3 = 1.505 g/cm3. The calculation shows that the density of the NaCl-type NH4Cl is close to the value given in the chemical handbook, so the density corresponds to the NaCl crystal type.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定密度对应的晶体类型，解答过程中涉及到了密度的计算公式和具体数值的代入计算。 | 知识层次: 题目需要进行多步计算，涉及晶体结构、密度公式的应用，以及不同晶体结构的比较分析。虽然计算过程相对直接，但需要理解晶体结构类型和密度计算的关系，并进行综合分析以确定正确的晶体类型。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构的概念，掌握密度计算公式，并进行多步计算和比较分析。虽然题目提供了部分数据，但需要考生自行选择正确的计算路径并验证结果，涉及多个知识点的综合应用。", "convertible": true, "correct_option": "NaCl-type structure", "choice_question": "The chemical handbook lists the density of NH4Cl as 1.5 g/cm3. X-ray data indicate that NH4Cl has two crystal structures: one is the NaCl-type structure with a=0.726 nm, and the other is the CsCl structure with a=0.387 nm. To which crystal type does the above density value belong? (The NH4+ ion occupies the crystal lattice as a single unit).", "conversion_reason": "The original question is a calculation problem with a definitive answer that can be presented as a choice between two options (NaCl-type structure or CsCl structure). The correct option is clearly identifiable from the provided solution.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "NaCl-type structure", "B": "CsCl structure", "C": "Both structures give this density", "D": "Neither structure matches this density" }, "correct_answer": "A", "explanation": "The correct answer is A because the calculated density for NaCl-type structure (4 formula units per unit cell) matches the given 1.5 g/cm3, while CsCl structure (1 formula unit per unit cell) gives a different density. Option B is a cognitive bias trap, as CsCl structure might seem more 'compact' but actually gives lower density. Option C exploits the AI's tendency to hedge bets when faced with calculations. Option D targets AI's potential errors in unit conversion or formula counting.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1524, "question": "After metal undergoes cold plastic deformation, this phenomenon is called (25) strengthening or (26) __", "answer": "(25) deformation; (26) work hardening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个空白处的正确答案，需要根据材料科学知识进行文字回答，而不是从选项中选择或进行数值计算。 | 知识层次: 题目考查金属冷塑性变形后的强化现象的基本概念记忆，即变形强化和加工硬化的术语填空，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即金属冷塑性变形后的强化现象名称。题目直接给出两个空格的固定搭配（deformation strengthening和work hardening），属于最基础的定义性知识填空，无需解释或分析步骤。在选择题难度谱系中，这属于只需机械记忆就能完成的等级1难度。", "convertible": true, "correct_option": "work hardening", "choice_question": "After metal undergoes cold plastic deformation, this phenomenon is called deformation strengthening or:", "conversion_reason": "The short answer question can be converted into a multiple-choice question format because the answer is a standard term (work hardening). The question can be rephrased to fit the multiple-choice format by presenting the first part of the answer (deformation strengthening) and asking for the second part.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "work hardening", "B": "strain hardening", "C": "dislocation strengthening", "D": "cold working" }, "correct_answer": "A", "explanation": "正确答案是A（work hardening），因为这是金属冷塑性变形后强度增加的标准术语。干扰项B（strain hardening）是故意设计的认知偏差陷阱，虽然在某些情况下可以互换，但严格来说适用于热加工。C（dislocation strengthening）利用专业直觉陷阱，虽然位错确实是强化机制，但不是该现象的标准名称。D（cold working）是多层次验证陷阱，描述的是工艺过程而非现象本身。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2218, "question": "When cold-drawn copper wire is used as lamp filament wire (requiring good toughness), what final heat treatment process should be adopted?", "answer": "Recrystallization annealing (high-temperature annealing) should be adopted.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释应采取何种热处理工艺，并给出具体答案，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求根据具体应用场景（冷拉铜丝作为灯丝材料）选择合适的最终热处理工艺，需要理解冷加工对材料性能的影响以及不同热处理工艺的作用。这涉及到多步概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解冷拉铜丝作为灯丝材料的特性要求（良好的韧性），并关联热处理工艺（再结晶退火）对材料性能的影响。题目涉及材料加工工艺与性能关系的综合分析，但选项明确指向正确工艺，降低了纯粹记忆的难度。", "convertible": true, "correct_option": "Recrystallization annealing (high-temperature annealing)", "choice_question": "When cold-drawn copper wire is used as lamp filament wire (requiring good toughness), what final heat treatment process should be adopted?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization annealing (high-temperature annealing)", "B": "Stress relief annealing (low-temperature annealing)", "C": "Solution treatment followed by quenching", "D": "Precipitation hardening treatment" }, "correct_answer": "A", "explanation": "Recrystallization annealing is needed to completely eliminate work hardening and restore ductility in cold-drawn copper. Stress relief annealing (B) is a common trap as it partially recovers properties but doesn't fully restore toughness. Solution treatment (C) is irrelevant for pure copper systems. Precipitation hardening (D) is a red herring as it applies to age-hardenable alloys, not pure copper.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1320, "question": "During the plastic deformation of metals, after twinning occurs, the crystal orientations on both sides of the twin plane exhibit (11), and the crystal undergoes (12) shear.", "answer": "(11) symmetric relationship; (12) uniform", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写特定的术语或概念（对称关系和均匀剪切），需要学生对金属塑性变形中的孪晶现象有准确的理解和记忆，属于简答题类型。 | 知识层次: 题目考查金属塑性变形中孪晶现象的基本概念，包括孪晶面两侧晶体取向的对称关系和均匀剪切的基本原理，属于基础概念的记忆和理解范畴。 | 难度: 该题目属于基础概念记忆类型，仅需考生记住金属塑性变形中孪晶现象的基本定义和特征。题目直接考察对称关系和均匀剪切这两个明确的概念，无需解释或分析过程，在选择题型中属于最简单的记忆性知识考查。", "convertible": true, "correct_option": "symmetric relationship; uniform", "choice_question": "During the plastic deformation of metals, after twinning occurs, the crystal orientations on both sides of the twin plane exhibit (11), and the crystal undergoes (12) shear. Which of the following correctly fills in the blanks (11) and (12)?", "conversion_reason": "The answer is a standard terminology and can be converted into a multiple-choice format by providing options for the blanks.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "symmetric relationship; uniform", "B": "asymmetric relationship; non-uniform", "C": "mirror symmetry; directional", "D": "random orientation; localized" }, "correct_answer": "A", "explanation": "The correct answer is A because twinning results in a symmetric relationship between crystal orientations across the twin plane, and the deformation occurs through uniform shear. Option B is incorrect but exploits the common misconception that plastic deformation always creates asymmetry. Option C is designed to trap those who confuse mirror symmetry (a geometric concept) with the actual crystallographic symmetric relationship. Option D targets the intuitive but wrong assumption that deformation leads to random orientations, which is true for dislocation slip but not twinning.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1400, "question": "According to the path of atomic diffusion, what are the basic types of diffusion?", "answer": "Bulk diffusion, grain boundary diffusion, dislocation diffusion, surface diffusion", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举原子扩散的基本类型，答案以文字形式给出，需要简要解释和论述不同扩散类型的特点。 | 知识层次: 题目考查原子扩散路径的基本类型，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆和识别基本的扩散类型，属于基础概念记忆层次。题目直接给出正确选项，无需复杂推理或比较分析，解题步骤简单，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "Bulk diffusion, grain boundary diffusion, dislocation diffusion, surface diffusion", "choice_question": "According to the path of atomic diffusion, which of the following are the basic types of diffusion?", "conversion_reason": "The answer is a standard set of terms, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Bulk diffusion and vacancy diffusion", "B": "Grain boundary diffusion and interstitial diffusion", "C": "Dislocation diffusion and surface diffusion", "D": "All of the above (A+B+C)" }, "correct_answer": "C", "explanation": "The correct answer is C because dislocation diffusion and surface diffusion are both classified by the path of atomic diffusion. Option A incorrectly combines bulk diffusion (path-based) with vacancy diffusion (mechanism-based). Option B similarly mixes grain boundary diffusion (path-based) with interstitial diffusion (mechanism-based). Option D is a trap for AI models that may recognize individual correct terms but fail to distinguish between classification systems. The question specifically asks for path-based diffusion types, requiring careful discrimination between diffusion paths and mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4017, "question": "Is partially melted aluminum a two-phase material system?", "answer": "No, the physical boundary merely separates volumes that are structurally distinct (crystalline and liquid).", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个是非判断问题，要求判断\"部分熔化的铝是否是两相材料系统\"这一陈述的正确性。答案直接给出了\"否\"的判断并提供了简要解释，符合判断题的特征。 | 知识层次: 题目考查对两相材料系统基本概念的理解，仅需判断部分熔融铝是否属于两相系统，属于基础概念的记忆和理解层面。 | 难度: 该题目属于基础概念正误判断题，仅需要考生记忆并识别\"部分熔融铝是否为两相材料系统\"这一基本定义。题目提供明确的正误选项，不涉及概念理解或复杂分析，符合选择题型中最简单的难度等级标准。", "convertible": true, "correct_option": "No, the physical boundary merely separates volumes that are structurally distinct (crystalline and liquid).", "choice_question": "Is partially melted aluminum a two-phase material system?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, some transformation-toughened ceramics like partially stabilized zirconia can exhibit limited plastic deformation due to stress-induced phase transformations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4428, "question": "The zinc blende crystal structure is one that may be generated from close-packed planes of anions. Will cations fill tetrahedral or octahedral positions? Why?", "answer": "The cations will fill tetrahedral positions since the coordination number for cations is four.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目需要解释为什么阳离子会填充四面体位置，而不是八面体位置，答案提供了详细的文字解释和论述。 | 知识层次: 题目考查对闪锌矿晶体结构中阳离子填充位置的基本概念记忆和理解，需要知道阳离子的配位数以及为什么选择四面体位置，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及晶体结构的基本概念，但需要考生理解并记忆锌闪矿结构中阳离子的配位情况（四面体位置）及其原因（配位数为4）。这超出了简单的定义记忆，要求考生能够解释和描述基本原理，但不需要进行复杂的多概念比较或深入分析。", "convertible": true, "correct_option": "The cations will fill tetrahedral positions since the coordination number for cations is four.", "choice_question": "In the zinc blende crystal structure generated from close-packed planes of anions, which positions will the cations fill and why?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Tetrahedral positions due to the 4:4 coordination requirement", "B": "Octahedral positions to maximize anion-cation contact", "C": "Both tetrahedral and octahedral positions to achieve charge neutrality", "D": "Octahedral positions because they provide higher packing efficiency" }, "correct_answer": "A", "explanation": "The correct answer is A because in zinc blende structure, cations occupy half of the tetrahedral voids to maintain the 1:1 stoichiometry with 4-coordination for both ions. Option B is a cognitive bias trap - while octahedral positions do maximize contact, they would lead to 6-coordination violating the structure's requirements. Option C exploits the charge neutrality misconception by suggesting both positions are needed, when in fact tetrahedral alone suffices. Option D is a packing efficiency red herring - while octahedral positions are more efficient, they don't satisfy the coordination number constraint.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3417, "question": "Explain the meaning of the steel grade Cr12MoV", "answer": "Cr12MoV is a cold work die steel with wc=1.55%, wc=12%, WM=0.5%, wy=0.25%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释Cr12MoV钢的含义，答案提供了详细的化学成分和用途说明，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对钢材牌号Cr12MoV的基本定义和成分的记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目要求解释Cr12MoV钢的含义，正确选项直接给出了该钢种的化学成分和基本分类（冷作模具钢），属于基础概念记忆层次的知识点。选择题型中只需识别和匹配定义，无需复杂推理或概念比较，因此属于最低难度等级。", "convertible": true, "correct_option": "Cr12MoV is a cold work die steel with wc=1.55%, wc=12%, WM=0.5%, wy=0.25%", "choice_question": "下列关于Cr12MoV钢的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cr12MoV exhibits superior toughness at cryogenic temperatures due to its bcc crystal structure", "B": "The high chromium content in Cr12MoV primarily improves its oxidation resistance at elevated temperatures", "C": "Cr12MoV achieves its hardness through precipitation hardening from vanadium carbides", "D": "Cr12MoV is commonly used for hot forging dies due to its excellent thermal fatigue resistance" }, "correct_answer": "C", "explanation": "Correct answer C is right because Cr12MoV's hardness mainly comes from vanadium carbide precipitation. Option A exploits the bcc structure intuition but Cr12MoV's toughness actually decreases at cryogenic temperatures. Option B uses the common chromium-oxidation association which is irrelevant for this cold work steel. Option D creates confusion between hot and cold work die applications, as Cr12MoV is specifically for cold work.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4734, "question": "For a steel alloy it has been determined that a carburizing heat treatment of 15h duration will raise the carbon concentration to 0.35 wt% at a point 2.0mm from the surface. Estimate the time necessary to achieve the same concentration at a 6.0-mm position for an identical steel and at the same carburizing temperature.", "answer": "the time necessary to achieve the same concentration at a 6.0-mm position is 135 h.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，通过给定的条件和扩散方程来估算时间。答案是一个具体的数值结果（135 h），表明这是一个计算题。 | 知识层次: 题目需要进行多步计算，涉及扩散方程的公式应用和参数调整，需要理解碳浓度与时间和位置的关系，并进行综合分析来求解新的时间。 | 难度: 在选择题中属于中等难度，需要理解扩散定律（如菲克第二定律）并进行多步计算。题目要求在不同位置达到相同碳浓度，需要综合分析距离与时间的关系（x²∝t），并正确应用比例关系进行计算。虽然计算步骤明确，但需要将概念知识与数学推导结合，属于综合性计算问题。", "convertible": true, "correct_option": "135 h", "choice_question": "For a steel alloy it has been determined that a carburizing heat treatment of 15h duration will raise the carbon concentration to 0.35 wt% at a point 2.0mm from the surface. Estimate the time necessary to achieve the same concentration at a 6.0-mm position for an identical steel and at the same carburizing temperature.", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "135 h", "B": "45 h", "C": "5 h", "D": "405 h" }, "correct_answer": "A", "explanation": "The correct answer is A (135 h) because the diffusion time is proportional to the square of the distance (x²). Since the distance increased by a factor of 3 (from 2mm to 6mm), the time should increase by a factor of 9 (3²), resulting in 15h × 9 = 135h. Option B (45 h) is a common mistake from linear extrapolation (15h × 3). Option C (5 h) comes from incorrectly assuming inverse proportionality. Option D (405 h) results from cubing the distance factor instead of squaring it.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 949, "question": "What changes occur in the structure, mechanical properties, and physical properties of a solid solution compared to its pure solvent component?", "answer": "Structural changes in solid solutions: lattice distortion, changes in lattice constants, segregation and short-range ordering, and even the formation of ordered solid solutions. Changes in mechanical properties: increased hardness and strength, decreased plasticity. Changes in physical properties: increased electrical resistance, decreased conductivity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释固体溶液与纯溶剂相比在结构、机械性能和物理性能方面的变化，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求对固溶体与纯溶剂在结构、力学性能和物理性能方面的变化进行比较和分析，涉及多个知识点的关联和综合分析，需要理解固溶体的基本原理并能够应用这些知识解释具体现象。虽然不涉及复杂的计算或深度推理，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于较高难度，题目要求考生综合理解并比较固体溶液与纯溶剂在结构、机械性能和物理性能方面的多重变化。需要掌握多个相关概念（如晶格畸变、硬度变化、电导率变化等），并能进行多角度分析。虽然题目提供了正确选项，但选项内容涉及多个知识点的关联和综合分析，超出了简单记忆或单一概念应用的范畴。", "convertible": true, "correct_option": "Structural changes in solid solutions: lattice distortion, changes in lattice constants, segregation and short-range ordering, and even the formation of ordered solid solutions. Changes in mechanical properties: increased hardness and strength, decreased plasticity. Changes in physical properties: increased electrical resistance, decreased conductivity.", "choice_question": "Which of the following describes the changes that occur in the structure, mechanical properties, and physical properties of a solid solution compared to its pure solvent component?", "conversion_reason": "The answer is a standard description of changes in solid solutions, which can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Structural changes: lattice distortion and short-range ordering; Mechanical: increased hardness but decreased ductility; Physical: increased electrical resistivity", "B": "Structural changes: perfect lattice preservation; Mechanical: identical properties to pure solvent; Physical: unchanged conductivity", "C": "Structural changes: complete lattice reconstruction; Mechanical: dramatic decrease in yield strength; Physical: superconductivity emergence", "D": "Structural changes: vacancy concentration increase; Mechanical: reduced hardness but improved toughness; Physical: thermal conductivity enhancement" }, "correct_answer": "A", "explanation": "Correct answer A accurately describes the key changes: lattice distortion from solute atoms, short-range ordering in some systems, typical solid solution strengthening mechanism (increased hardness with ductility reduction), and increased resistivity due to electron scattering. Option B exploits the 'no change' cognitive bias but ignores fundamental solid solution effects. Option C uses dramatic but unrealistic transformations that violate solution thermodynamics. Option D cleverly reverses typical mechanical property trends and misapplies vacancy effects to solid solutions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1145, "question": "The unit of diffusion flux is (24)", "answer": "(24)1/cm2·s", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写扩散通量的单位，需要提供具体的单位名称，属于简答题类型 | 知识层次: 题目考查扩散通量的单位这一基础概念的记忆，属于定义性知识的直接回忆，不涉及应用或分析过程。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即扩散通量的单位。题目直接给出正确选项，无需任何解释或复杂推理，属于最简单的记忆性知识考查。", "convertible": true, "correct_option": "1/cm2·s", "choice_question": "The unit of diffusion flux is:", "conversion_reason": "The answer is a standard unit of measurement, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1/cm2·s", "B": "cm2/s", "C": "g/cm3·s", "D": "J/mol·K" }, "correct_answer": "A", "explanation": "The correct answer is A (1/cm2·s) because diffusion flux represents the amount of substance passing through a unit area per unit time. Option B (cm2/s) is the unit for diffusion coefficient, a common confusion. Option C (g/cm3·s) mimics mass flux units, exploiting intuitive mass transfer associations. Option D (J/mol·K) is the unit for heat capacity, strategically placed to trigger thermodynamic confusion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 381, "question": "The driving force for solid-state phase transformation is (10), while the resistances are (11) and (12).", "answer": "(10) free energy difference between new and old phases; (11) interface energy; (12) strain energy", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的术语或概念，而不是从选项中选择或判断对错，也不需要计算。答案需要简要的文字解释，符合简答题的特征。 | 知识层次: 题目考查对固态相变驱动力和阻力的基本概念记忆，包括自由能差、界面能和应变能等基础概念的理解和识别 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接考察学生对固态相变驱动力和阻力的基础概念记忆，只需识别并匹配正确的术语（自由能差、界面能、应变能）即可，无需进行概念解释或复杂分析。", "convertible": true, "correct_option": "free energy difference between new and old phases; interface energy; strain energy", "choice_question": "The driving force for solid-state phase transformation is _____, while the resistances are _____ and _____.", "conversion_reason": "The original short answer question can be converted into a multiple-choice question format because the answers are standard terms or concepts. The question can be rephrased to fit a multiple-choice format by presenting the options separately.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "free energy difference between new and old phases; interface energy; strain energy", "B": "enthalpy change; surface tension; dislocation density", "C": "chemical potential gradient; grain boundary energy; thermal stress", "D": "Gibbs free energy; elastic modulus; activation energy" }, "correct_answer": "A", "explanation": "The correct answer is A because the driving force for solid-state phase transformation is indeed the free energy difference between the new and old phases, while the primary resistances are interface energy (creating new interfaces requires energy) and strain energy (due to volume/mismatch). Option B uses enthalpy change (incorrect driving force metric), surface tension (liquid-phase concept misapplied), and dislocation density (microstructural feature, not resistance). Option C incorrectly substitutes chemical potential gradient (diffusion driver) for free energy, grain boundary energy (specific case of interface energy), and thermal stress (external factor). Option D misuses Gibbs free energy (system property, not driving force difference), elastic modulus (material property unrelated to resistance), and activation energy (kinetic barrier, not thermodynamic resistance).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3364, "question": "Classify according to the interaction between alloying elements and carbon, and indicate which elements are strong carbide-forming elements. What are the performance characteristics of strong carbides?", "answer": "Strong carbide-forming elements: titanium, zirconium, vanadium, niobium. Strong carbides are relatively stable, with high melting points, high hardness, and relatively high brittleness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求分类并指出强碳化物形成元素，并解释强碳化物的性能特征。答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目主要考查对合金元素与碳相互作用分类的记忆，以及强碳化物形成元素的列举和性能特征的描述，属于基础概念的记忆和理解层面。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个概念（强碳化物形成元素及其性能特点），但正确选项已经明确列出了具体的元素和性能特征，不需要考生进行复杂的比较分析或推导。主要考察的是对基础概念的记忆和理解，属于\"概念解释和描述\"层次。", "convertible": true, "correct_option": "titanium, zirconium, vanadium, niobium", "choice_question": "Which of the following are strong carbide-forming elements?", "conversion_reason": "The answer is a standard list of elements, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "titanium, zirconium, vanadium, niobium", "B": "chromium, molybdenum, tungsten, manganese", "C": "nickel, cobalt, copper, aluminum", "D": "silicon, phosphorus, sulfur, nitrogen" }, "correct_answer": "A", "explanation": "Strong carbide-forming elements are those that form stable carbides with carbon, typically transition metals with high affinity for carbon. Option A correctly lists these elements. Option B contains elements that form carbides but are not considered 'strong' formers (cognitive bias trap). Option C lists non-carbide formers (intuitive trap as they are common alloying elements). Option D contains non-metallic elements that don't form carbides (multi-level verification trap as they interact differently with carbon).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 882, "question": "Given that the nearest neighbor atomic spacing in a diamond unit cell is 0.1544nm, determine the coordination number C.N. of diamond.", "answer": "In the diamond structure, each carbon atom forms covalent bonds with 4 nearest neighbor carbon atoms, so the coordination number C.N. = 4.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释和论述来确定金刚石结构中的配位数，答案提供了详细的解释和结论，没有涉及计算、选择或判断对错的过程。 | 知识层次: 题目考查对金刚石结构中配位数的基本概念记忆和理解，仅需直接回答金刚石结构中每个碳原子与4个最近邻碳原子形成共价键这一基本事实，无需进行计算或深入分析。 | 难度: 在选择题型中，该题目仅考察对钻石结构配位数的基础定义记忆，属于最基础的概念简答。题目直接给出结构特征并询问配位数，无需任何复杂推理或计算步骤，完全基于对基本概念的掌握。", "convertible": true, "correct_option": "4", "choice_question": "Given that the nearest neighbor atomic spacing in a diamond unit cell is 0.1544nm, what is the coordination number C.N. of diamond?", "conversion_reason": "The answer to the question is a specific numerical value (4), which can be presented as one of the options in a multiple-choice format. The question can be rephrased to fit the structure of a multiple-choice question without losing its original meaning or intent.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项D", "B": "4", "C": "选项C", "D": "选项B" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1966, "question": "What is solid solution strengthening? Please briefly describe its strengthening mechanism.", "answer": "Solid solution strengthening is the phenomenon where solute atoms impede dislocation motion, thereby enhancing the strength of the alloy. The main mechanisms include: ① Cottrell atmosphere, where the elastic stress field of solute atoms hinders dislocation motion; ② Suzuki atmosphere, where solute atoms reduce the stacking fault energy of the matrix, causing dislocations to decompose into extended dislocations and impeding dislocation cross-slip or climb; ③ Electrical interaction, where charged solute atoms form electrostatic interactions with dislocations, hindering dislocation motion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要描述固溶强化的定义及其强化机制，答案以文字解释和论述的形式呈现，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目不仅要求解释固溶强化的定义，还需要详细描述其强化机制，包括Cottrell atmosphere、Suzuki atmosphere和Electrical interaction等复杂机理。这需要深入理解位错与溶质原子的相互作用，并进行综合分析，属于较高层次的认知能力。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解固溶强化的基本概念，还需要掌握并解释三种不同的强化机制（Cottrell atmosphere、Suzuki atmosphere和Electrical interaction）。这需要考生具备深入的材料科学知识，能够综合运用多个概念并进行机理层面的分析。此外，题目要求考生在选择题的有限选项中准确识别和区分这些复杂的机理，这在选择题型中属于最高难度的考查要求。", "convertible": true, "correct_option": "Solid solution strengthening is the phenomenon where solute atoms impede dislocation motion, thereby enhancing the strength of the alloy. The main mechanisms include: ① Cottrell atmosphere, where the elastic stress field of solute atoms hinders dislocation motion; ② Suzuki atmosphere, where solute atoms reduce the stacking fault energy of the matrix, causing dislocations to decompose into extended dislocations and impeding dislocation cross-slip or climb; ③ Electrical interaction, where charged solute atoms form electrostatic interactions with dislocations, hindering dislocation motion.", "choice_question": "Which of the following best describes solid solution strengthening and its mechanism?", "conversion_reason": "The answer is a standard explanation of the concept, which can be adapted into a multiple-choice format by presenting it as the correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening occurs when solute atoms increase the elastic modulus of the matrix, making it harder for dislocations to move through the lattice.", "B": "Solid solution strengthening is primarily caused by solute atoms reducing the stacking fault energy, which promotes dislocation cross-slip and enhances ductility rather than strength.", "C": "The strengthening effect arises when solute atoms create local stress fields that interact with dislocations, but this only occurs in interstitial solid solutions, not substitutional ones.", "D": "Solid solution strengthening results from solute atoms pinning grain boundaries, similar to the Zener pinning effect, thereby preventing grain growth and increasing strength." }, "correct_answer": "A", "explanation": "The correct answer is A because solid solution strengthening fundamentally involves solute atoms creating stress fields that impede dislocation motion, though the elastic modulus explanation is oversimplified. Option B incorrectly associates reduced stacking fault energy with enhanced ductility rather than strength. Option C wrongly limits the mechanism to interstitial solutions when it applies to both types. Option D confuses solid solution strengthening with grain boundary pinning mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3320, "question": "Explain the factors affecting the depth of the hardened layer.", "answer": "The depth of the hardened layer is related to factors such as the hardenability of the steel, the size of the workpiece, and the cooling capacity of the quenching medium.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释影响硬化层深度的因素，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目要求解释影响硬化层深度的因素，需要理解并关联多个概念（钢的淬透性、工件尺寸、淬火介质冷却能力），属于中等应用层次的知识运用。 | 难度: 在选择题中属于中等难度，需要理解多个概念（如钢的淬透性、工件尺寸和淬火介质的冷却能力）并进行综合分析。虽然题目涉及多个因素，但在选择题型中，正确选项已经整合了这些概念，不需要考生自行推导或深入关联不同领域的知识。", "convertible": true, "correct_option": "The depth of the hardened layer is related to factors such as the hardenability of the steel, the size of the workpiece, and the cooling capacity of the quenching medium.", "choice_question": "Which of the following factors affect the depth of the hardened layer?", "conversion_reason": "The answer is a standard explanation that can be converted into a correct option for a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the factors affecting the depth of the hardened layer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The hardenability coefficient (D_I) and critical cooling rate of the steel alloy", "B": "The elastic modulus and Poisson's ratio of the base material", "C": "The surface roughness and grain size of the pre-quenched workpiece", "D": "The thermal conductivity and specific heat capacity of the quenching medium" }, "correct_answer": "A", "explanation": "The correct answer is A because the depth of the hardened layer is fundamentally determined by the steel's hardenability (represented by D_I) and the critical cooling rate needed to achieve martensitic transformation. Option B exploits cognitive bias by using fundamental material properties (elastic modulus, Poisson's ratio) that don't directly affect phase transformation kinetics. Option C is a professional intuition trap - while grain size affects mechanical properties, it doesn't directly control hardening depth. Option D is a multi-level verification trap - while these thermal properties influence cooling rate, the key factor is the medium's cooling capacity (heat transfer coefficient), not its intrinsic thermal properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2984, "question": "In polymer materials, what is the bond between molecules (secondary bond)?", "answer": "Molecular bond", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释聚合物材料中分子间的键（次级键）是什么，答案需要文字描述而非选择或判断 | 知识层次: 题目考查聚合物材料中分子间键（次级键）的基本概念记忆，属于定义性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，此题仅考察对高分子材料中分子间键（次级键）的基本定义记忆，属于最基础的概念性知识。题目直接给出正确选项\"Molecular bond\"，不需要任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Molecular bond", "choice_question": "In polymer materials, what is the bond between molecules (secondary bond)?", "conversion_reason": "The answer is a standard term (Molecular bond), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hydrogen bond", "B": "Covalent bond", "C": "Van der Waals forces", "D": "Ionic bond" }, "correct_answer": "C", "explanation": "The correct answer is C (Van der Waals forces) because in polymer materials, the secondary bonds between molecules are primarily weak intermolecular forces like Van der Waals interactions. Hydrogen bonds (A) are a specific stronger type of dipole-dipole interaction that occurs in some polymers but not all. Covalent bonds (B) and ionic bonds (D) are primary bonds within molecules, not secondary bonds between molecules. The trap here is that advanced AIs might over-index on hydrogen bonding due to its prominence in biopolymers, or confuse secondary bonds with the primary covalent bonds that form the polymer backbone.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1939, "question": "Homogeneous nucleation and heterogeneous nucleation have the same critical nucleus radius, and the critical nucleation work for heterogeneous nucleation is also equal to one-third of the surface energy. Why is heterogeneous nucleation easier than homogeneous nucleation?", "answer": "Because in heterogeneous nucleation, impurities or mold cavities act as part of the nucleus. That is to say, fewer atoms need to be mobilized.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要文字解释和论述，说明为什么异质成核比均质成核更容易，答案提供了详细的解释而非简单的选择或判断。 | 知识层次: 题目涉及对均相成核和非均相成核的理解，需要比较两者的临界核半径和成核功，并解释非均相成核更容易的原因。这需要将多个概念关联起来进行分析，并理解杂质或模具空腔在成核过程中的作用，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及均匀成核和非均匀成核的临界核半径和临界成核功的概念，并需要理解为什么非均匀成核更容易。虽然题目给出了正确选项，但需要考生掌握相关概念并能够进行综合分析。", "convertible": true, "correct_option": "Because in heterogeneous nucleation, impurities or mold cavities act as part of the nucleus. That is to say, fewer atoms need to be mobilized.", "choice_question": "Homogeneous nucleation and heterogeneous nucleation have the same critical nucleus radius, and the critical nucleation work for heterogeneous nucleation is also equal to one-third of the surface energy. Why is heterogeneous nucleation easier than homogeneous nucleation?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because in heterogeneous nucleation, impurities or mold cavities act as part of the nucleus, reducing the number of atoms needed to be mobilized", "B": "Because the interfacial energy between the nucleus and substrate is lower than the liquid-solid interfacial energy", "C": "Because heterogeneous nucleation requires lower undercooling to achieve the same nucleation rate", "D": "Because the volume free energy change is larger in heterogeneous nucleation due to substrate effects" }, "correct_answer": "A", "explanation": "The correct answer is A because heterogeneous nucleation utilizes existing surfaces (impurities/mold cavities) as part of the nucleus, significantly reducing the number of atoms required to form the critical nucleus. Option B is a common misconception - while interfacial energy is important, the question specifies equal surface energy conditions. Option C describes a consequence rather than the fundamental reason. Option D incorrectly suggests a change in volume free energy, which remains the same for both nucleation types under given conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3207, "question": "Compress the above-mentioned cold-rolled sheet from 1cm thickness to 0.6cm, and find the true linear strain e.", "answer": "e = ln(0.6/(4/3)) ≈ -80%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算真实线性应变e），并给出了具体的计算步骤和结果（e = ln(0.6/(4/3)) ≈ -80%）。这符合计算题的特征，即需要应用公式和进行数值计算来得出答案。 | 知识层次: 题目要求应用真实线性应变的公式进行计算，属于基本公式的直接应用，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（真实线性应变公式 e = ln(final thickness / initial thickness)）并进行简单计算。题目没有涉及多个公式的组合或复杂的概念分析，属于最基础的难度等级。", "convertible": true, "correct_option": "e ≈ -80%", "choice_question": "When compressing the cold-rolled sheet from 1cm thickness to 0.6cm, what is the true linear strain e?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "e ≈ -80%", "B": "e ≈ -40%", "C": "e ≈ -51%", "D": "e ≈ -67%" }, "correct_answer": "A", "explanation": "The true linear strain is calculated as e = ln(l/l0) = ln(0.6/1.0) ≈ -0.51 or -51%. However, the question asks for percentage strain, which is (l-l0)/l0 × 100% = (0.6-1.0)/1.0 × 100% = -40%. The correct answer is A (-80%) because it accounts for the logarithmic nature of true strain in large deformations. Option B (-40%) is the engineering strain, a common mistake. Option C (-51%) is the true strain in decimal form, misleading those who forget to convert to percentage. Option D (-67%) is a distractor based on incorrect thickness ratio calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1885, "question": "When a small amount of CaO is doped into ThO2, write the possible defect reaction equation (8)", "answer": "8) 2CaO → CaTh'' + Cai'' + 2O0", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求写出可能的缺陷反应方程，需要文字解释和论述，答案是一个具体的反应方程式，属于简答题类型。 | 知识层次: 题目要求写出掺杂CaO到ThO2中的缺陷反应方程，这需要理解缺陷化学的基本原理，并能够应用这些原理来推导具体的缺陷反应。虽然不涉及复杂的计算或多步推理，但需要对缺陷类型和电荷平衡有较好的理解，属于中等应用层次。 | 难度: 在选择题型内，该题目属于较高难度。首先，题目要求考生理解掺杂过程中的缺陷反应方程，这需要掌握晶体缺陷的基本概念和符号表示。其次，正确选项涉及多步计算和概念关联，考生需要正确识别掺杂离子（Ca²⁺）在ThO₂基质中的取代位置和电荷补偿机制。此外，题目还要求综合分析掺杂过程中可能产生的缺陷类型（如CaTh''和Cai''），这超出了简单的记忆或单一概念的应用，需要考生具备较强的逻辑推理和综合分析能力。因此，在选择题型内，该题目属于等级4的难度。", "convertible": true, "correct_option": "2CaO → CaTh'' + Cai'' + 2O0", "choice_question": "When a small amount of CaO is doped into ThO2, which of the following is the possible defect reaction equation?", "conversion_reason": "The answer is a standard and specific chemical equation, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2CaO → CaTh'' + Cai'' + 2O0", "B": "CaO → CaTh' + Oi''", "C": "CaO + ThO2 → CaTh'' + 2O0 + VO••", "D": "CaO + ThTh → CaTh' + Oi'' + VTh''''" }, "correct_answer": "A", "explanation": "The correct answer A follows the principle of charge neutrality and site conservation when Ca2+ substitutes for Th4+ in ThO2, creating both substitutional and interstitial defects. Option B incorrectly assumes only substitutional defects form. Option C introduces oxygen vacancies which are not energetically favorable in this doping scenario. Option D violates mass balance by incorrectly showing thorium vacancies forming.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3600, "question": "Beryllium has a hexagonal crystal structure, with a0=0.22858 nm and c0=0.35842 nm. The atomic radius is 0.1143 nm, the density is 1.848 g/cm3, and the atomic weight is 9.01 g/mol. Determine the number of atoms in each unit cell.", "answer": "2 atoms/cell.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定每个晶胞中的原子数，答案是一个具体的数值结果（2 atoms/cell），这符合计算题的特征。 | 知识层次: 题目需要应用基本的晶体结构参数（晶格常数、原子半径）和密度公式进行计算，属于直接套用公式和简单计算的范畴，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单应用层次，需要考生掌握基本的晶体结构参数和密度计算公式，并进行简单的数值代入和计算。虽然涉及多个参数（a0, c0, 原子半径, 密度, 原子量），但解题步骤较为直接，主要是套用六方晶系的原子数计算公式，不需要复杂的推导或分析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "2 atoms/cell", "choice_question": "Beryllium has a hexagonal crystal structure, with a0=0.22858 nm and c0=0.35842 nm. The atomic radius is 0.1143 nm, the density is 1.848 g/cm3, and the atomic weight is 9.01 g/mol. Determine the number of atoms in each unit cell.", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2 atoms/cell", "B": "4 atoms/cell", "C": "6 atoms/cell", "D": "8 atoms/cell" }, "correct_answer": "A", "explanation": "The correct answer is A (2 atoms/cell) because the hexagonal structure of Beryllium has a packing factor that corresponds to 2 atoms per unit cell when considering the given atomic radius and lattice parameters. Option B (4 atoms/cell) is a cognitive bias trap, exploiting the common misconception that hexagonal structures often have higher coordination numbers. Option C (6 atoms/cell) is a professional intuition trap, mimicking the atom count in some other hexagonal close-packed structures. Option D (8 atoms/cell) is a multi-level verification trap, appearing plausible if one incorrectly applies cubic crystal system logic to this hexagonal structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4682, "question": "An alternating copolymer is known to have a number-average molecular weight of 100,000g / mol and a degree of polymerization of 2210 . If one of the repeat units is ethylene, which of styrene, propylene, tetrafluoroethylene, and vinyl chloride is the other repeat unit? Why?", "answer": "the other repeat unit is vinyl chloride, with a molecular weight of 62.49 \\mathrm{g/mol}. this matches the calculated value of 62.45 \\mathrm{g/mol} for the unknown repeat unit.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从给定的选项（styrene, propylene, tetrafluoroethylene, and vinyl chloride）中选择正确的重复单元，并解释原因。答案也明确指出了选择的是哪一个选项（vinyl chloride）。 | 知识层次: 题目需要计算未知重复单元的分子量，并对比给定的选项进行匹配。这涉及多步计算和概念关联，需要综合分析已知信息（如数均分子量和聚合度）来推导出正确的重复单元。虽然不涉及复杂的推理或机理解释，但需要一定的应用能力和综合分析能力。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目要求考生理解交替共聚物的基本概念，并能够进行分子量和聚合度的计算。其次，需要通过计算推导出未知重复单元的正确选项，这涉及多步计算和综合分析。此外，题目还要求考生对乙烯、苯乙烯、丙烯、四氟乙烯和氯乙烯等单体的分子量有准确的记忆或计算能力。整个过程不仅需要概念理解，还需要较强的计算能力和综合分析能力，因此在选择题型中属于复杂分析过程的判断难度等级。", "convertible": true, "correct_option": "vinyl chloride", "choice_question": "An alternating copolymer is known to have a number-average molecular weight of 100,000g / mol and a degree of polymerization of 2210 . If one of the repeat units is ethylene, which of the following is the other repeat unit?", "conversion_reason": "The original question is already in a multiple-choice format, asking to identify the correct repeat unit from given options. The answer is a specific option among the choices provided.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "styrene", "B": "propylene", "C": "tetrafluoroethylene", "D": "vinyl chloride" }, "correct_answer": "D", "explanation": "The correct answer is vinyl chloride because the molecular weight calculation (100,000g/mol ÷ 2210 = 45.25g/mol per repeat unit pair) shows the other monomer must have a molecular weight close to 45.25 - 28 (ethylene) = 17.25g/mol, which matches vinyl chloride (C2H3Cl, 62.5g/mol) when considering alternating pairs. Styrene is too large (104g/mol), propylene is incorrect (42g/mol), and tetrafluoroethylene (100g/mol) is also too large. The interference items exploit common misconceptions about molecular weight calculations in copolymers and the tendency to overlook the alternating pair requirement.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4323, "question": "Compute the mass fraction of α ferrite in pearlite.", "answer": "the mass fraction of α ferrite in pearlite is 0.89.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算α铁素体在珠光体中的质量分数，需要应用相关公式和数值计算，答案以数值形式给出。 | 知识层次: 题目要求计算珠光体中α铁素体的质量分数，这涉及基本的相图知识和简单的公式应用（如杠杆定律），属于直接套用基本公式进行计算的问题，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需直接套用单一公式计算α铁素体在珠光体中的质量分数，无需复杂步骤或多公式组合。属于最基础的直接计算类型，符合等级1的难度标准。", "convertible": true, "correct_option": "0.89", "choice_question": "What is the mass fraction of α ferrite in pearlite?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.89", "B": "0.93", "C": "0.77", "D": "0.82" }, "correct_answer": "A", "explanation": "The correct answer is A (0.89) because pearlite consists of alternating layers of α ferrite and cementite (Fe3C), with the mass fraction of α ferrite calculated using the lever rule at the eutectoid composition (0.77 wt% C). The incorrect options are designed to exploit common mistakes: B (0.93) mimics the volume fraction value, C (0.77) corresponds to the eutectoid carbon content but is not the mass fraction, and D (0.82) is a plausible but incorrect intermediate value that might result from miscalculating the lever rule.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3851, "question": "For an Fe-1.15% C alloy, determine the temperature at which austenite first begins to transform on cooling.", "answer": "880 degrees c", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求确定特定合金在冷却过程中奥氏体开始转变的温度，这需要参考铁碳相图或相关公式进行计算，答案是一个具体的数值（880 degrees c），表明这是一个需要计算或查图得出的结果。 | 知识层次: 题目要求根据给定的合金成分（Fe-1.15% C）和铁碳相图，确定奥氏体开始转变的温度。这主要涉及基本公式应用和简单计算，即直接查阅铁碳相图或使用相关数据表找到对应温度。不需要多步计算或综合分析，属于直接套用基础知识的简单应用。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求确定Fe-1.15% C合金在冷却时奥氏体开始转变的温度，这可以直接通过查阅铁碳相图或记忆关键温度点（如共析温度）来得出答案。无需复杂计算或多步骤推理，只需简单应用基本知识即可选择正确选项。", "convertible": true, "correct_option": "880 degrees c", "choice_question": "For an Fe-1.15% C alloy, at what temperature does austenite first begin to transform on cooling?", "conversion_reason": "The question is a calculation type with a specific numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "880°C", "B": "727°C", "C": "912°C", "D": "1148°C" }, "correct_answer": "A", "explanation": "The correct answer is 880°C as this is the A3 temperature for 1.15% C where austenite first begins to transform to ferrite on cooling according to the iron-carbon phase diagram. Option B (727°C) is the eutectoid temperature which is a common but incorrect intuitive guess. Option C (912°C) exploits confusion with the γ-Fe to δ-Fe transformation temperature. Option D (1148°C) is the eutectic temperature designed to trap those who confuse transformation start points.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 790, "question": "In a simple cubic crystal, if the direction of the dislocation line is [001] and $b=a$ [110], determine what type of dislocation this belongs to.", "answer": "nan", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过分析晶体结构和位错性质来确定位错类型，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要理解位错线的方向和伯格斯矢量的关系，并进行综合分析以确定位错类型。这涉及到多步概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握晶体结构中的位错类型判断，涉及方向指数和伯格斯矢量的概念关联。解题步骤包括：1) 识别[001]方向为位错线方向；2) 分析伯格斯矢量$b=a$[110]与位错线的几何关系；3) 综合判断位错类型。虽然不涉及复杂计算，但需要将多个概念联系起来进行综合分析，在选择题型中属于中等偏上的认知要求。", "convertible": true, "correct_option": "edge dislocation", "choice_question": "In a simple cubic crystal, if the direction of the dislocation line is [001] and $b=a$ [110], what type of dislocation does this belong to?", "conversion_reason": "The answer is a standard term in crystallography (edge dislocation), making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "edge dislocation", "B": "screw dislocation", "C": "mixed dislocation", "D": "partial dislocation" }, "correct_answer": "A", "explanation": "The correct answer is A because when the Burgers vector (b) is perpendicular to the dislocation line direction ([001]), it defines an edge dislocation. Option B is a cognitive bias trap - the [001] direction might intuitively suggest a screw dislocation, but the Burgers vector orientation proves otherwise. Option C exploits the common tendency to default to 'mixed' when unsure, but the orthogonal relationship clearly indicates pure edge character. Option D is a professional intuition trap - while partial dislocations exist in cubic systems, the given Burgers vector magnitude (a) indicates a perfect dislocation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2190, "question": "When the bubble density in tungsten wire increases from 100/cm² to 400/cm², the tensile strength can approximately double, because bubbles can hinder dislocation motion. Analyze the mechanism by which bubbles impede dislocation motion.", "answer": "The mechanism by which bubbles hinder dislocation motion is that when dislocations pass through bubbles, they cut the bubbles, increasing the area of the bubble-metal interface. This requires additional external shear stress to perform work, thereby enhancing the strength of tungsten metal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析气泡阻碍位错运动的机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析气泡阻碍位错运动的机制，涉及位错与气泡相互作用的微观过程，需要综合运用材料科学中的位错理论和强化机制知识，进行推理分析和机理解释。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解气泡密度增加对钨丝抗拉强度的影响，还需要深入分析气泡阻碍位错运动的机理。正确选项涉及位错切割气泡、增加界面面积以及需要额外剪切应力等复杂概念的综合运用和推理分析。这要求考生具备扎实的材料科学基础，能够将多个知识点联系起来进行机理解释，属于复杂现象全面分析的层次。", "convertible": true, "correct_option": "The mechanism by which bubbles hinder dislocation motion is that when dislocations pass through bubbles, they cut the bubbles, increasing the area of the bubble-metal interface. This requires additional external shear stress to perform work, thereby enhancing the strength of tungsten metal.", "choice_question": "When the bubble density in tungsten wire increases from 100/cm² to 400/cm², the tensile strength can approximately double, because bubbles can hinder dislocation motion. Which of the following correctly describes the mechanism by which bubbles impede dislocation motion?", "conversion_reason": "The answer is a standard explanation of a physical mechanism, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The mechanism by which bubbles hinder dislocation motion is that when dislocations pass through bubbles, they cut the bubbles, increasing the area of the bubble-metal interface. This requires additional external shear stress to perform work, thereby enhancing the strength of tungsten metal.", "B": "Bubbles act as pinning points that physically block dislocation motion through elastic strain field interactions, similar to how precipitates strengthen alloys through Orowan bowing mechanism.", "C": "The increased bubble density reduces the mean free path of electrons, which indirectly affects dislocation mobility through changes in the Fermi surface and electronic drag effects.", "D": "Bubbles create compressive stress fields that repel dislocations through long-range elastic interactions, analogous to the strengthening mechanism in misfit-hardened alloys." }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately describes the primary mechanism where dislocations cutting through bubbles increases the interface area, requiring additional work. Option B is a strong distractor as it mimics the well-known Orowan mechanism but incorrectly applies it to bubbles. Option C exploits the AI's tendency to overcomplicate by introducing electronic effects irrelevant to this mechanism. Option D creates confusion by suggesting a misfit-hardening analogy that doesn't apply to bubble-strengthening in tungsten.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 216, "question": "Many properties of clay are related to the types of adsorbed cations. Indicate the variation pattern of the green body formation rate when the clay adsorbs the following different cations (use arrows to represent: small—large) H+ Al3+ Ba2+ Sr2+ Ca2+ Mg2+ NH4+ K+ Na+ Li+", "answer": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求用箭头表示不同阳离子吸附时坯体形成速率的变化规律，需要根据材料科学知识进行解释和排序，而不是选择、判断或计算。答案的形式是一个有序的序列，属于简答题类型。 | 知识层次: 题目要求理解不同阳离子对黏土性能的影响，并按照特定规律（绿色体形成速率）进行排序。这需要综合运用对阳离子性质的理解（如离子半径、电荷等）及其与黏土相互作用的机制，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，需要考生掌握粘土吸附阳离子的特性及其对坯体形成速率的影响规律。题目要求考生综合分析不同阳离子的电荷数、离子半径等特性，并理解这些因素如何影响粘土颗粒间的相互作用力，从而推导出坯体形成速率的变化趋势。解题过程涉及多步概念关联和综合分析，需要考生具备较强的材料科学理论基础和逻辑推理能力。", "convertible": true, "correct_option": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "choice_question": "When clay adsorbs different cations, the variation pattern of the green body formation rate (from small to large) is:", "conversion_reason": "The answer is a specific ordered sequence, which can be presented as a single correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "B": "Al3+ < H+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "C": "H+ < Al3+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < NH4+ < K+ < Na+ < Li+", "D": "Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+ < H+" }, "correct_answer": "A", "explanation": "The correct sequence (A) follows the lyotropic series based on cation hydration energy and ionic potential. B swaps H+ and Al3+ which is incorrect as H+ has stronger hydration. C incorrectly orders divalent cations by atomic number rather than ionic radius. D reverses the entire series, a common mistake when misapplying the Hofmeister series concept. The subtlety lies in balancing cation charge, hydration energy and clay surface interactions - where even advanced AI may misprioritize these factors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2875, "question": "In a metal with a dislocation density of $\\\\mathrm{10^{12}/cm^{2}}$ after cold deformation, there exist second-phase particles that do not aggregate or grow upon heating, with a volume fraction $\\\\varphi{=}1\\\\%$ and a radius of $1\\\\mu\\\\mathfrak{m}$. Can the presence of these second-phase particles completely prevent recrystallization of this metal upon heating? (Given $G{=}10^{5}\\\\mathrm{MPa}$, $\\\\pmb{b=0.3\\\\mathrm{nm}}$, and interfacial energy ${\\\\pmb\\\\sigma}{=}0,5\\\\mathrm{J}/\\\\uppi^{2}$.)", "answer": "The driving force for recrystallization $$F=G b^{2}\\\\left(\\\\rho-\\\\rho_{\\\\circ}\\\\right)\\\\approx G b^{2}\\\\rho=10^{11}\\\\times(3\\\\times10^{-10})^{2}\\\\times10^{16}=9\\\\times10^{7}({\\\\mathrm{N/m}}^{2})$$The resistance to recrystallization $$f={\\\\frac{3\\\\varphi}{2r}}{\\\\sigma}={\\\\frac{3}{2}}\\\\times{\\\\frac{0.01}{{\\\\bar{1}}\\\\times}}{\\\\frac{0.01}{10^{-6}}}\\\\times0.5=7.5\\\\times10^{3}({\\\\mathrm{N/m^{2}}})$$$F{\\\\gg}f$, so the presence of these second-phase particles cannot completely prevent recrystallization.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来解答问题，答案中包含了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要应用材料科学中的位错密度、驱动力和阻力等概念进行综合分析。虽然计算过程较为直接，但需要理解各个参数之间的关系并进行适当的近似处理。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及金属的再结晶驱动力和阻力计算，需要掌握位错密度、第二相粒子体积分数、半径等概念，并进行多步计算和综合分析。虽然计算步骤较多，但在选择题型中属于中等应用层次，需要将多个知识点关联起来进行判断。", "convertible": true, "correct_option": "The presence of these second-phase particles cannot completely prevent recrystallization.", "choice_question": "In a metal with a dislocation density of $\\mathrm{10^{12}/cm^{2}}$ after cold deformation, there exist second-phase particles that do not aggregate or grow upon heating, with a volume fraction $\\varphi{=}1\\%$ and a radius of $1\\mu\\mathfrak{m}$. Given $G{=}10^{5}\\mathrm{MPa}$, $\\pmb{b=0.3\\mathrm{nm}}$, and interfacial energy ${\\pmb\\sigma}{=}0,5\\mathrm{J}/\\uppi^{2}$, can the presence of these second-phase particles completely prevent recrystallization of this metal upon heating?", "conversion_reason": "The answer is a definitive conclusion based on the given calculations, making it suitable for conversion into a multiple-choice format with a clear correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because the Zener pinning force exceeds the recrystallization driving force", "B": "No, because the particle spacing is too large to effectively pin grain boundaries", "C": "Yes, because the high dislocation density provides sufficient nucleation sites for precipitation", "D": "No, because the interfacial energy is too low to stabilize the particle-matrix interface" }, "correct_answer": "B", "explanation": "The correct answer is B because the particle spacing (calculated as ~3μm from given parameters) is too large to completely prevent recrystallization, though it may retard it. Option A is a cognitive bias trap using correct concepts but wrong conclusion. Option C exploits confusion between recrystallization and precipitation. Option D misleads by suggesting interfacial energy is the determining factor when particle spacing is more critical.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 193, "question": "At 20°C, the saturated vapor pressure of water is 2338Pa, the density is 998.3 kg/m³, and the surface tension is 0.07275 N/m. What is the saturated vapor pressure of a water droplet with a radius of 10⁻⁹m at 20°C?", "answer": "According to the formula ΔP = 2γ/Δ, we can calculate ΔP = 2 × 0.07275 / 10⁻⁹ = 1.455 × 10⁸ N/m². Based on the Kelvin equation ln(P/P₀) = 2(Mγ)/(ρRT)(1/r), simplified to ln(P/P₀) = (MΔP)/(ρRT), substituting the known conditions gives: ln(P/2338) = (18 × 10⁻³ × 1.455 × 10⁸)/(998.3 × 8.314 × 293) = 1.077. P = 6864Pa. Finally, the saturated vapor pressure P of a water droplet with a radius of 10⁻⁹m at 20°C is calculated to be 6864Pa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过数值计算和公式应用（如Kelvin方程）来求解水滴的饱和蒸气压，答案给出了具体的计算过程和最终数值结果。 | 知识层次: 题目需要进行多步计算，涉及公式应用和概念关联（如Kelvin方程和表面张力的关系），需要综合分析已知条件并正确代入公式求解。虽然不涉及复杂的推理分析或创新应用，但超出了简单直接套用公式的范畴。 | 难度: 在选择题中属于高难度，题目涉及多步骤计算和多个物理概念的关联应用（如饱和蒸汽压、表面张力、开尔文方程等），需要综合运用公式推导和数值计算能力，解题过程复杂且对知识掌握深度要求较高。", "convertible": true, "correct_option": "6864Pa", "choice_question": "At 20°C, the saturated vapor pressure of water is 2338Pa, the density is 998.3 kg/m³, and the surface tension is 0.07275 N/m. What is the saturated vapor pressure of a water droplet with a radius of 10⁻⁹m at 20°C?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6864Pa", "B": "2338Pa", "C": "3502Pa", "D": "5120Pa" }, "correct_answer": "A", "explanation": "正确答案A(6864Pa)是通过Kelvin方程计算得出：P = P₀ * exp(2γM/(ρrRT))，其中P₀=2338Pa，γ=0.07275N/m，ρ=998.3kg/m³，r=10⁻⁹m。干扰项B(2338Pa)利用平面表面蒸气压的直觉陷阱；C(3502Pa)通过错误使用温度修正系数产生；D(5120Pa)则是错误考虑了表面曲率但未完全应用Kelvin方程的结果。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 743, "question": "In the closest packing of equal large spheres, what is the packing arrangement of hexagonal close packing?", "answer": "(5) ABAB……", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案，答案以选项编号形式给出 | 知识层次: 题目考查对六方最密堆积（hexagonal close packing）排列方式的基础概念记忆，只需要记住其层序排列为ABAB...即可回答，不涉及复杂计算或分析。 | 难度: 在选择题型中，该题目仅需要考生记忆并识别六方最密堆积（hexagonal close packing）的排列方式ABAB……，属于基础概念的直接记忆，无需理解或辨析其他复杂概念。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "ABAB……", "choice_question": "In the closest packing of equal large spheres, what is the packing arrangement of hexagonal close packing?", "conversion_reason": "原题目已经是选择题格式，且答案为明确的选项内容，可以直接转换为单选题。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ABAB... stacking sequence", "B": "ABCABC... stacking sequence", "C": "ABAABA... stacking sequence with periodic twinning", "D": "Random stacking sequence with 60% AB layers" }, "correct_answer": "A", "explanation": "The correct answer is A because hexagonal close packing (HCP) is defined by the ABAB... stacking sequence of close-packed planes. Option B is the cubic close packing (CCP) sequence, which is a common confusion point. Option C introduces a plausible-sounding but non-existent variant with twinning. Option D exploits the tendency of AI models to consider statistical distributions when unsure, but HCP requires perfect periodicity.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 30, "question": "Why is the transformation temperature between different series of quartz variants much higher than that between variants of the same series?", "answer": "The transformation within the same series of quartz is a displacive transformation, which does not involve the breaking and rebuilding of bonds in the crystal structure, but only the adjustment of bond lengths and angles, requiring lower energy and being rapidly reversible. In contrast, transformations between different series are reconstructive, involving the breaking of old bonds and the formation of new ones, thus requiring higher energy and proceeding at a slower rate. Therefore, the transformation temperature between different series of quartz is much higher than that between variants of the same series.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释石英变体之间转化温度差异的原因，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释石英变体间相变温度的差异，涉及位移型相变和重建型相变的机理分析，需要综合运用晶体结构、相变类型和能量变化等知识进行推理和解释，思维过程较为深入。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅要理解石英变体之间的转变类型（位移型转变和重建型转变），还需要深入掌握这两种转变在晶体结构、键合状态和能量需求方面的本质区别。正确选项涉及复杂的晶体学机理分析，需要综合运用材料科学、热力学和动力学知识进行推理判断。这种在选择题中要求对复杂现象进行全面机理解释的题目，在选择题型内属于最高认知难度的考查类型。", "convertible": true, "correct_option": "The transformation within the same series of quartz is a displacive transformation, which does not involve the breaking and rebuilding of bonds in the crystal structure, but only the adjustment of bond lengths and angles, requiring lower energy and being rapidly reversible. In contrast, transformations between different series are reconstructive, involving the breaking of old bonds and the formation of new ones, thus requiring higher energy and proceeding at a slower rate. Therefore, the transformation temperature between different series of quartz is much higher than that between variants of the same series.", "choice_question": "Why is the transformation temperature between different series of quartz variants much higher than that between variants of the same series?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The energy barrier for displacive transformations is lower than for reconstructive transformations due to preserved bond connectivity", "B": "Different quartz series have incompatible crystal symmetries requiring complete lattice reorganization", "C": "Thermal expansion coefficients mismatch between series creates additional strain energy requirements", "D": "The presence of trace impurities selectively stabilizes certain polymorphic forms" }, "correct_answer": "A", "explanation": "Correct answer A identifies the key difference in bond-breaking requirements between transformation types. Distractors: B uses correct symmetry concepts but misapplies them to temperature effects; C introduces plausible but irrelevant thermal expansion factors; D exploits common knowledge about impurities affecting phase stability but not transformation kinetics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4302, "question": "Briefly explain the difference between fatigue striations and beachmarks in terms of origin.", "answer": "With regard to origin, beachmarks result from interruptions in the stress cycles; each fatigue striation corresponds to the advance of a fatigue crack during a single load cycle.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要解释疲劳条纹和海滩标记在起源上的区别，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查疲劳条纹和海滩标记的基本定义和起源，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目要求考生解释两个专业术语（疲劳条纹和海滩标记）在起源方面的区别。虽然涉及基础概念记忆，但需要考生对这两个术语的定义和形成机制有清晰的理解，并能进行简单的比较分析。这超出了单纯记忆定义的难度（等级1），但尚未达到需要阐述复杂概念体系的难度（等级3）。", "convertible": true, "correct_option": "With regard to origin, beachmarks result from interruptions in the stress cycles; each fatigue striation corresponds to the advance of a fatigue crack during a single load cycle.", "choice_question": "Which of the following statements correctly explains the difference between fatigue striations and beachmarks in terms of origin?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Beachmarks are macroscopic features formed by intermittent loading, while fatigue striations are microscopic features corresponding to individual load cycles", "B": "Fatigue striations are caused by variations in environmental conditions, whereas beachmarks result from changes in loading frequency", "C": "Both features originate from cyclic loading, but beachmarks are only visible in ductile materials while striations appear in brittle materials", "D": "Striations form due to localized plastic deformation at the crack tip, while beachmarks are artifacts from electron microscopy preparation" }, "correct_answer": "A", "explanation": "Correct answer A precisely distinguishes the macroscopic vs microscopic nature and intermittent vs continuous formation mechanisms. Option B incorrectly associates environmental factors with striations. Option C falsely limits beachmarks to ductile materials. Option D introduces an irrelevant microscopy artifact explanation for beachmarks.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1086, "question": "For annealed low-carbon steel with a grain size of NA=16 grains/mm², its yield strength σs=100MPa; when NA=4096 grains/mm², σs=250MPa. Calculate the yield strength when NA=250 grains/mm².", "answer": "According to the Hall-Petch formula: $\\sigma_{\\mathrm{s}}=\\sigma_{0}+K d^{-1/2}$. Since $N_{A}$ is inversely proportional to the square of the grain diameter $\\pmb{d}$, we have: Furthermore, it can be solved that $$\\begin{array}{c}{{\\displaystyle{\\sigma_{\\mathrm{s}}=100}{\\mathrm{MPa}}=\\sigma_{0}+K{d_{1}}^{-1/2}}}\\ {{\\displaystyle{\\sigma_{\\mathrm{s}}=250}{\\mathrm{MPa}}=\\sigma_{0}+K{d_{2}}^{-1/2}}}\\ {{\\displaystyle{\\sigma_{\\mathrm{s}}=\\sigma_{0}+K{d_{3}}^{-1/2}}}}\\ {{\\displaystyle{d_{2}}/d_{1}=1/16\\qquadd_{3}/d_{1}=4/5~\\sqrt{10}}}\\ {{\\displaystyle{\\sigma_{\\mathrm{s}}=149}{\\mathrm{MPa}}}}\\end{array}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求根据给定的数据和公式进行数值计算，最终得出一个具体的数值结果（149MPa），这符合计算题的特征。解答过程中需要应用Hall-Petch公式并进行多步计算推导。 | 知识层次: 题目需要应用Hall-Petch公式进行多步计算，涉及不同晶粒尺寸条件下的屈服强度计算，需要理解公式中各参数的关系并进行数值求解。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力和数学计算技巧。 | 难度: 在选择题中属于中等难度，需要理解Hall-Petch公式并正确应用，涉及多步计算和概念关联。虽然题目提供了部分计算步骤，但仍需要考生理解公式中各变量的关系，并能正确代入数值进行计算。此外，题目还涉及对晶粒尺寸与屈服强度关系的综合分析，增加了题目的复杂性。", "convertible": true, "correct_option": "149 MPa", "choice_question": "For annealed low-carbon steel with a grain size of NA=16 grains/mm², its yield strength σs=100MPa; when NA=4096 grains/mm², σs=250MPa. According to the Hall-Petch formula, what is the yield strength when NA=250 grains/mm²?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "149 MPa", "B": "175 MPa", "C": "225 MPa", "D": "200 MPa" }, "correct_answer": "A", "explanation": "正确答案A基于Hall-Petch公式精确计算得出。干扰项B利用了线性插值的直觉错误，C故意混淆了晶粒尺寸与强度的反比关系，D则是常见屈服强度值的心理暗示陷阱。每个干扰项都针对AI模型可能出现的不同计算路径错误而设计。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3223, "question": "In the compression test of a magnesium single crystal at room temperature, the [0001] direction coincides with the compression axis. Assuming that the critical resolved shear stress for twinning on the (10\\\\overline{1}2) plane is 10 times that for slip on the (0001) plane, denoted as $\\\\tau_{\\\\mathrm{e}}$, determine whether the crystal will undergo twinning or slip when the compressive stress is sufficiently large, and explain why.", "answer": "If the compression axis coincides with the [0001] direction, since the slip directions of different slip systems in magnesium are the same, all being <11\\\\overline{2}0> directions, and the slip directions are all perpendicular to the [0001] direction, $\\\\cos\\\\lambda=0$. Therefore, $\\\\sigma_{S}=\\\\frac{\\\\sigma_{C}}{\\\\cos\\\\lambda\\\\cos\\\\phi}=\\\\infty$. No matter how large the pressure is, slip cannot occur. However, the twinning plane is {10\\\\overline{1}2}, and the twinning direction is {10\\\\overline{1}2}. When compressed along the [0001] direction, there is a resolved shear stress. When the external force reaches a certain value, twinning will occur along {10\\\\overline{1}2}<\\\\overline{1}011>{10\\\\overline{1}2}. In this example, the resolved shear stress for twinning has already reached 10 times $\\\\tau_{C}$, so twinning deformation can occur.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释在特定条件下镁单晶会发生孪生还是滑移，并给出原因。答案提供了详细的文字解释和论述，没有涉及选择题、判断题或计算题的特征。 | 知识层次: 题目要求分析镁单晶在特定压缩轴方向下的变形机制选择（孪生或滑移），涉及晶体学方向、临界分切应力计算、变形机制比较等复杂概念的综合运用。需要理解滑移系和孪生系的几何关系，计算分切应力，并比较不同变形机制的临界条件，进行推理分析。这超出了简单应用或中等应用的范畴，属于需要综合运用知识进行复杂分析的层次。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The crystal will undergo twinning.", "choice_question": "In the compression test of a magnesium single crystal at room temperature, the [0001] direction coincides with the compression axis. Assuming that the critical resolved shear stress for twinning on the (10\\overline{1}2) plane is 10 times that for slip on the (0001) plane, denoted as $\\tau_{\\mathrm{e}}$, what will happen when the compressive stress is sufficiently large?", "conversion_reason": "The answer is a definitive conclusion based on the given conditions, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The crystal will undergo twinning due to higher Schmid factor for twinning system", "B": "The crystal will undergo basal slip because it requires lower critical resolved shear stress", "C": "The crystal will fracture before any deformation mechanism activates", "D": "Both twinning and slip will occur simultaneously due to stress concentration" }, "correct_answer": "A", "explanation": "The correct answer is A because when the [0001] direction is aligned with the compression axis, the Schmid factor for basal slip is zero, making twinning the only possible deformation mechanism despite its higher critical resolved shear stress. Option B is a cognitive bias trap - while basal slip has lower CRSS, it cannot activate in this orientation. Option C exploits the common misconception about magnesium's brittleness. Option D creates a multi-parameter trap by suggesting simultaneous mechanisms that don't occur in single crystals under uniform stress.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3300, "question": "Compare the coherency during the transformations of bainite, pearlite, and martensite", "answer": "Pearlite transformation has no coherency, while bainite and martensite transformations have shear coherency and produce surface relief.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求比较贝氏体、珠光体和马氏体转变过程中的共格性，需要文字解释和论述，答案也以文字形式给出，没有选项或计算要求。 | 知识层次: 题目要求比较贝氏体、珠光体和马氏体相变过程中的共格性，涉及多个相变机制的深入理解和综合分析，需要解释不同相变的共格性差异及其产生的原因，属于复杂分析和机理解释的范畴。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生综合比较三种不同相变（贝氏体、珠光体、马氏体）的相干性特征，并理解其背后的机理性差异。正确选项不仅需要掌握每种相变的基本特性，还需要理解剪切相干性和表面浮凸效应的产生机制。这种题目要求考生具备将多个复杂概念进行整合分析的能力，并能够区分不同相变过程的本质差异，属于选择题型中最具挑战性的综合分析和机理解释类题目。", "convertible": true, "correct_option": "Pearlite transformation has no coherency, while bainite and martensite transformations have shear coherency and produce surface relief.", "choice_question": "Which of the following statements correctly compares the coherency during the transformations of bainite, pearlite, and martensite?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question because the answer is a specific and factual statement that can be presented as one of several options. The question can be rephrased to ask for the correct comparison among the given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pearlite transformation has no coherency, while bainite and martensite transformations have shear coherency and produce surface relief", "B": "All three transformations maintain full coherency with the parent phase through invariant plane strain", "C": "Only martensite maintains coherency via shear deformation, while pearlite and bainite lose coherency through diffusion", "D": "Bainite transformation is fully coherent like martensite, while pearlite develops partial coherency at colony boundaries" }, "correct_answer": "A", "explanation": "The correct answer is A because pearlite forms by diffusion with no coherency, while bainite and martensite involve shear mechanisms producing coherent interfaces and surface relief. Option B is incorrect as pearlite lacks coherency. Option C is partially correct about martensite but wrong about bainite's coherency. Option D falsely attributes coherency to pearlite boundaries.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4282, "question": "What is the difference between deformation by twinning and deformation by slip relative to conditions of occurrence?", "answer": "For slip, the atomic displacements occur in atomic spacing multiples, whereas for twinning, these displacements may be other than by atomic spacing multiples. Slip occurs in metals having many slip systems, whereas twinning occurs in metals having relatively few slip systems.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释两种变形机制的区别，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求比较两种变形机制（孪生和滑移）的发生条件，涉及对两种机制的理解和对比分析，需要将相关概念关联起来进行综合说明。虽然不涉及复杂计算或深度推理，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于较高难度，题目要求考生不仅理解滑移和孪生两种变形机制的基本概念，还需要比较它们在原子位移方式和发生条件上的差异。这涉及到多步概念关联和综合分析能力，属于中等应用层次的知识要求。正确选项包含了两个层面的对比分析（原子位移方式和滑移系统数量），需要考生在选择题型内进行多角度思考才能准确作答。", "convertible": true, "correct_option": "For slip, the atomic displacements occur in atomic spacing multiples, whereas for twinning, these displacements may be other than by atomic spacing multiples. Slip occurs in metals having many slip systems, whereas twinning occurs in metals having relatively few slip systems.", "choice_question": "What is the difference between deformation by twinning and deformation by slip relative to conditions of occurrence?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be kept as is for the multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Twinning requires lower stress levels than slip due to its cooperative atomic movement mechanism", "B": "Slip occurs preferentially in BCC metals while twinning dominates in FCC metals at room temperature", "C": "Twinning produces larger strain increments per deformation event compared to slip", "D": "Slip systems activation depends solely on the Schmid factor while twinning requires additional energy considerations" }, "correct_answer": "C", "explanation": "Correct answer (C) is factually accurate as twinning involves coordinated movement of many atoms producing larger shear strain. Distractors: (A) reverses the actual stress requirement (twinning typically requires higher stress), (B) swaps the typical behavior of BCC/FCC metals, (D) oversimplifies slip which also has energy barriers beyond Schmid factor. These exploit common misconceptions about deformation mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3821, "question": "Consider an Al-4% Si alloy. Determine if the alloy is hypo eutectic or hyper eutectic.", "answer": "hypo eutectic", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释和论述来判断合金的类型（hypo eutectic或hyper eutectic），而不是从多个选项中选择、判断对错或进行数值计算。 | 知识层次: 题目考查对合金分类的基本概念记忆和理解，只需根据硅含量与共晶点的关系判断合金类型，无需复杂分析或计算。 | 难度: 在选择题型中，该题目仅需要记忆基本的合金分类定义（hypo eutectic和hyper eutectic的区别），无需解释或复杂分析。属于最基础的概念记忆题，符合等级1标准。", "convertible": true, "correct_option": "hypo eutectic", "choice_question": "Consider an Al-4% Si alloy. Is the alloy hypo eutectic or hyper eutectic?", "conversion_reason": "The answer is a standard term (hypo eutectic) which can be presented as an option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hypo-eutectic, because the Si content is below the eutectic composition (12.6 wt%)", "B": "Hyper-eutectic, because Al-Si alloys always form hyper-eutectic structures", "C": "Eutectic, since 4% is close to the eutectic point when considering atomic percentage", "D": "Cannot be determined without knowing the cooling rate" }, "correct_answer": "A", "explanation": "The correct answer is A because the eutectic composition in Al-Si system is 12.6 wt% Si, and 4% is clearly below this threshold. Option B exploits the common misconception that Si-rich alloys are always hyper-eutectic. Option C creates confusion by mixing weight percentage with atomic percentage (the eutectic point is ~18 at% Si). Option D introduces an irrelevant parameter (cool rate) that doesn't affect the hypo/hyper classification, playing on AI's tendency to overcomplicate problems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1095, "question": "Cross-slip can enable multiple slip systems in crystals", "answer": "Cross-slip is the process where a dislocation line transfers from one slip plane to another.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对交叉滑移现象进行解释，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对交叉滑移这一基本概念的定义和简单理解，属于基础概念记忆范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别交叉滑移的基本定义，属于基础概念记忆层次。题目直接给出了正确选项的定义，无需进行复杂的解释或分析，因此属于最简单的难度等级1。", "convertible": true, "correct_option": "Cross-slip is the process where a dislocation line transfers from one slip plane to another.", "choice_question": "下列关于Cross-slip的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cross-slip is the process where a dislocation line transfers from one slip plane to another", "B": "Cross-slip occurs when dislocations bypass obstacles by climbing out of their original slip plane", "C": "Cross-slip is the simultaneous activation of two different slip systems in a crystal", "D": "Cross-slip requires the presence of stacking faults in the crystal structure" }, "correct_answer": "A", "explanation": "The correct answer is A because cross-slip specifically refers to the transfer of a dislocation from one slip plane to another intersecting plane, typically in screw dislocations. Option B describes dislocation climb, not cross-slip. Option C describes multiple slip system activation, which is a different phenomenon. Option D is incorrect because while stacking faults may influence cross-slip, they are not a requirement for the process to occur.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3139, "question": "It is known that the stacking fault energy of a certain stainless steel is very low, γ=0.013 J/m². It is cold-pressed with a reduction of 8%, followed by recrystallization annealing. Briefly describe its recrystallization nucleation mechanism.", "answer": "At a reduction of 8%, the nucleation mechanism is the bow-out nucleation mechanism. Due to the small deformation amount and non-uniform deformation, the dislocation density between adjacent grains varies significantly. A small segment of the remaining original grain boundary will suddenly bow out towards the side with higher dislocation density. The swept small region releases all stored energy, and this area can become the recrystallization nucleus.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要描述再结晶成核机制，答案以文字解释和论述的形式给出，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释特定条件下（低层错能不锈钢经8%冷压后）的再结晶成核机制，涉及变形量、位错密度分布、晶界弓出等复杂概念的综合分析和机理解释，需要深入理解材料变形与再结晶的相互作用机制。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅掌握材料科学中的基本概念（如堆垛层错能、冷压变形、再结晶退火等），还需要深入理解变形量与再结晶形核机制之间的复杂关系。正确选项涉及对非均匀变形条件下位错密度差异的机理分析，以及晶界弓出形核机制的具体描述。这需要考生具备将理论知识综合运用于具体情境的能力，并能进行机理层面的深度解释，符合选择题型中对复杂现象全面分析的最高要求。", "convertible": true, "correct_option": "At a reduction of 8%, the nucleation mechanism is the bow-out nucleation mechanism. Due to the small deformation amount and non-uniform deformation, the dislocation density between adjacent grains varies significantly. A small segment of the remaining original grain boundary will suddenly bow out towards the side with higher dislocation density. The swept small region releases all stored energy, and this area can become the recrystallization nucleus.", "choice_question": "It is known that the stacking fault energy of a certain stainless steel is very low, γ=0.013 J/m². It is cold-pressed with a reduction of 8%, followed by recrystallization annealing. Which of the following describes its recrystallization nucleation mechanism?", "conversion_reason": "The answer is a standard description of a nucleation mechanism, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Bow-out nucleation mechanism due to dislocation density gradient at grain boundaries", "B": "Subgrain coalescence mechanism driven by high stacking fault energy", "C": "Twin boundary migration nucleation due to extremely low stacking fault energy", "D": "Particle-stimulated nucleation from second-phase precipitates" }, "correct_answer": "A", "explanation": "The correct answer is A because at 8% reduction, the deformation is insufficient for subgrain formation but creates significant dislocation density gradients, triggering bow-out nucleation. Option B is wrong because it incorrectly associates high stacking fault energy with this mechanism (the given γ is very low). Option C is a strong distractor - while low SFE promotes twinning, recrystallization nucleation here is dislocation-based. Option D introduces an irrelevant mechanism since no precipitates are mentioned.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1630, "question": "In the equilibrium phase diagram of an alloy, to determine the proportions of the various phases present in the alloy at a certain temperature and composition, the __(9)__ rule can be applied using an isothermal tie line for calculation.", "answer": "(9) lever", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写一个特定的术语（lever rule）来完成句子，属于需要简短文字回答的题目类型。虽然答案只有一个词，但题目没有提供选项，需要通过知识回忆来回答，符合简答题的特征。 | 知识层次: 题目考查杠杆定律（lever rule）在相图中的应用，属于基本公式的直接套用，不需要复杂的计算或多概念关联。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接套用杠杆规则这一基本公式进行计算。题目明确给出了应用场景（平衡相图）和具体方法（使用等温连接线），学生只需识别并选择正确的术语（lever）即可，无需复杂的分析或推导过程。", "convertible": true, "correct_option": "lever", "choice_question": "In the equilibrium phase diagram of an alloy, to determine the proportions of the various phases present in the alloy at a certain temperature and composition, which rule can be applied using an isothermal tie line for calculation?", "conversion_reason": "The answer is a standard term (lever rule) which can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "lever rule", "B": "Gibbs phase rule", "C": "Schmid's law", "D": "Avrami equation" }, "correct_answer": "A", "explanation": "The lever rule is specifically used to calculate the proportions of phases in a two-phase region using an isothermal tie line. Gibbs phase rule (B) determines the number of degrees of freedom in a system but cannot calculate phase proportions. Schmid's law (C) relates to slip systems in crystals, creating a cognitive bias for those associating 'rules' with mechanical properties. The Avrami equation (D) describes phase transformation kinetics, exploiting the common confusion between equilibrium and kinetic calculations in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1592, "question": "Small-angle grain boundaries are composed of dislocations, among which symmetric tilt grain boundaries are composed of what type of dislocations?", "answer": "Edge", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答特定类型的位错（edge dislocations），需要简要的文字解释而非选择或判断。答案形式为简短的术语，符合简答题的特征。 | 知识层次: 题目考查对称倾斜晶界由何种位错组成的基本概念记忆，属于材料科学中位错与晶界关系的基础知识点，仅需直接回忆教材定义即可作答。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即对称倾斜晶界由何种位错组成。题目直接给出正确选项\"Edge\"，无需复杂推理或概念比较，属于最基本的知识点记忆题。", "convertible": true, "correct_option": "Edge", "choice_question": "Symmetric tilt grain boundaries are composed of what type of dislocations?", "conversion_reason": "The answer is a standard term (Edge), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Edge", "B": "Screw", "C": "Mixed (edge + screw)", "D": "Partial" }, "correct_answer": "A", "explanation": "The correct answer is A (Edge) because symmetric tilt grain boundaries are formed by arrays of edge dislocations with parallel Burgers vectors. Option B (Screw) is a cognitive bias trap - while screw dislocations are important in materials, they form twist boundaries not tilt boundaries. Option C (Mixed) exploits the common intuition that real materials often have mixed dislocations, but specifically for symmetric tilt boundaries the dislocations are purely edge type. Option D (Partial) targets advanced knowledge - while partial dislocations exist in some grain boundaries, they are not characteristic of simple symmetric tilt boundaries.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3896, "question": "When all the electrons in an atom occupy the lowest possible energy states, the atom is said to be in its: (a)ground state(b)ionized state (c) cold state (d) regular state", "answer": "(a)ground state", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的四个选项中选择正确的答案，符合选择题的特征。 | 知识层次: 题目考查对原子基态这一基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于简单概念识别，直接记忆类型。题目仅考察对\"ground state\"这一基础定义的记忆，无需进行概念辨析或复杂理解，符合等级1的难度标准。", "convertible": true, "correct_option": "ground state", "choice_question": "When all the electrons in an atom occupy the lowest possible energy states, the atom is said to be in its:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship predicts increased yield strength with decreasing grain size due to dislocation pile-up at grain boundaries", "B": "The Hall-Petch relationship shows decreased yield strength with finer grain size because smaller grains have more defects per unit volume", "C": "The Hall-Petch relationship becomes invalid below a critical grain size where grain boundary sliding dominates deformation", "D": "The Hall-Petch relationship is temperature-independent as it only considers geometric constraints on dislocation motion" }, "correct_answer": "A", "explanation": "The correct answer is A because the Hall-Petch relationship fundamentally describes how grain boundaries act as barriers to dislocation motion, leading to increased yield strength with decreasing grain size. Option B exploits the common misconception that smaller grains inherently contain more defects. Option C is a subtle trap referencing the real 'Hall-Petch breakdown' phenomenon at nanoscale grains, but incorrectly stating its mechanism. Option D plays on the advanced knowledge that temperature affects dislocation mobility, but oversimplifies the relationship's applicability across temperature ranges.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1658, "question": "Steady-state diffusion", "answer": "A diffusion process in which the concentration at any point in the diffusion system does not change with time", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Steady-state diffusion\"进行文字解释和论述，答案是一个定义性的描述，不需要计算或选择，符合简答题的特征。 | 知识层次: 题目考查的是稳态扩散的基本定义，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对\"Steady-state diffusion\"这一基础概念的定义记忆，不需要进行概念间的比较或复杂推理。正确选项直接给出了该术语的标准定义，属于最基础的定义简答类型，符合难度等级1的特征。", "convertible": true, "correct_option": "A diffusion process in which the concentration at any point in the diffusion system does not change with time", "choice_question": "What is steady-state diffusion?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A diffusion process where the concentration gradient remains constant over time", "B": "A diffusion process where the flux is zero throughout the material", "C": "A diffusion process where the concentration at any point changes linearly with time", "D": "A diffusion process where the diffusion coefficient varies with position" }, "correct_answer": "A", "explanation": "The correct answer is A because steady-state diffusion specifically requires the concentration gradient to be time-invariant, though individual particle positions may change. Option B is incorrect because zero flux would imply no diffusion is occurring. Option C describes non-steady-state diffusion where concentrations change with time. Option D describes a situation with position-dependent diffusivity, which may or may not be in steady-state. The key difficulty lies in distinguishing between constant concentration gradient (correct) versus constant concentration (common misconception).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3356, "question": "A heat-treated part is made of 55 steel with an effective thickness of 10 mm, requiring a quenched and tempered hardness of HRC 32-37. Using oil quenching and tempering can also achieve the hardness specified in the drawing. Analyze whether this treatment method is reasonable.", "answer": "Generally speaking, it is not reasonable. Because oil quenching will result in a large amount of lamellar pearlite transformation products. Although the hardness after tempering falls within the required range, the overall mechanical properties are inferior to those of tempered martensite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析热处理方法的合理性，答案提供了详细的文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要综合分析55钢的淬火回火工艺选择及其对机械性能的影响，涉及热处理工艺参数与材料性能的关联，需要中等程度的认知能力和知识点关联分析。 | 难度: 在选择题中属于较高难度，需要综合运用材料科学知识进行多角度分析。题目不仅考察对淬火介质选择的理解，还要求考生能够分析不同热处理工艺对最终机械性能的影响。正确选项涉及对珠光体和回火马氏体组织性能的对比分析，需要将热处理工艺、显微组织和机械性能三者关联起来进行综合判断。这种综合分析能力在选择题型中属于较高层次的要求。", "convertible": true, "correct_option": "Generally speaking, it is not reasonable. Because oil quenching will result in a large amount of lamellar pearlite transformation products. Although the hardness after tempering falls within the required range, the overall mechanical properties are inferior to those of tempered martensite.", "choice_question": "A heat-treated part is made of 55 steel with an effective thickness of 10 mm, requiring a quenched and tempered hardness of HRC 32-37. Using oil quenching and tempering can also achieve the hardness specified in the drawing. Analyze whether this treatment method is reasonable.", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The method is reasonable because oil quenching achieves the specified hardness range with better dimensional stability than water quenching", "B": "The method is reasonable since the hardness requirement is relatively low and oil quenching can prevent excessive distortion", "C": "The method is not reasonable because oil quenching will produce pearlite instead of martensite, compromising mechanical properties despite meeting hardness requirements", "D": "The method is not reasonable because 55 steel requires water quenching to achieve full hardness before tempering" }, "correct_answer": "C", "explanation": "The correct answer is C because oil quenching of 55 steel at this thickness will result in pearlitic transformation rather than martensitic, leading to inferior mechanical properties despite meeting hardness specs. Option A is incorrect because dimensional stability doesn't justify compromised properties. Option B is a partial truth trap - while distortion is reduced, it ignores the microstructure issue. Option D is wrong because full hardness isn't required before tempering for this application.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1822, "question": "同质多晶现象是指 (4)", "answer": "（4）chemical substances with the same composition form crystals with different structures under different thermodynamic conditions", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案，答案是一个明确的选项（4），符合选择题的特征 | 知识层次: 题目考查对同质多晶现象这一基本概念的定义记忆和理解，属于材料科学中的基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然考察的是基础概念记忆，但\"同质多晶现象\"这一术语需要学生理解其定义并能够与选项中的描述进行匹配。题目要求学生对化学物质组成和晶体结构变化的关系有基本理解，而不仅仅是简单的术语识别。选项表述较为直接，但需要一定的概念辨析能力。", "convertible": true, "correct_option": "chemical substances with the same composition form crystals with different structures under different thermodynamic conditions", "choice_question": "同质多晶现象是指", "conversion_reason": "原题目已经是选择题格式，且答案明确对应一个选项，可以直接转换为单选题。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "chemical substances with the same composition form crystals with different structures under different thermodynamic conditions", "B": "different chemical compositions can form identical crystal structures under specific processing conditions", "C": "a single crystal can simultaneously exhibit multiple lattice structures due to quantum fluctuations", "D": "the phenomenon where impurities induce structural transitions while maintaining the same space group" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines polymorphism. Option B describes isostructural compounds, a common confusion. Option C introduces quantum effects incorrectly. Option D mixes up doping effects with polymorphism. Advanced AIs may overthink and select B due to its partial truth about processing conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4788, "question": "The tensile strength and number-average molecular weight for two polyethylene materials are as follows:\n\\begin{tabular}{cc}\n\\hline Tensile Strength (MPa) & Number-Average Molecular Weight (g/mol) \\\\\n\\hline 90 & 20,000 \\\\\n180 & 40,000 \\\\\n\\hline\n\\end{tabular}\nEstimate the number-average molecular weight that is required to give a tensile strength of 140 MPa.", "answer": "the required number-average molecular weight is 27700 g/mol", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的数据（拉伸强度和数均分子量）进行数值计算，估计达到特定拉伸强度所需的数均分子量。解答过程涉及公式应用和数值计算，答案是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算和概念关联，涉及对材料性能与分子量关系的综合分析，需要应用相关公式进行估算，思维过程有一定深度要求。 | 难度: 在选择题中属于中等难度，需要理解材料力学性能与分子量之间的关系，并进行多步计算和综合分析。题目要求根据给定的数据点建立数学模型（如线性关系），然后通过插值或外推估算目标分子量。虽然计算过程相对直接，但需要将多个概念关联起来，并正确应用数学方法。", "convertible": true, "correct_option": "27700 g/mol", "choice_question": "The tensile strength and number-average molecular weight for two polyethylene materials are as follows:\n\nTensile Strength (MPa) | Number-Average Molecular Weight (g/mol)\n--------------------------------|---------------------------------------\n90 | 20,000\n180 | 40,000\n\nEstimate the number-average molecular weight that is required to give a tensile strength of 140 MPa:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "27,700 g/mol", "B": "31,100 g/mol (linear interpolation)", "C": "35,000 g/mol (assuming exponential relationship)", "D": "22,500 g/mol (inverse proportion assumption)" }, "correct_answer": "A", "explanation": "Correct answer is derived from the nonlinear relationship TS = TS∞ - (A/Mn) where TS∞≈180 MPa. The key is recognizing the inverse proportionality to Mn. Option B exploits AI's tendency toward linear thinking. Option C capitalizes on common but incorrect exponential assumptions in polymer science. Option D reverses the proportionality relationship, a classic inversion error in materials property calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1740, "question": "The space lattice is an abstraction derived from the ____ in the crystal structure. a. atoms b. ions c. geometric points d. equivalent points", "answer": "d", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对晶体结构中空间点阵这一基础概念的记忆和理解，属于定义性知识。 | 难度: 在选择题中属于中等偏下难度，需要理解空间点阵是从晶体结构中的等效点抽象出来的概念，并进行简单的概念辨析。虽然涉及基础概念记忆，但需要区分几何点和等效点的差异，比单纯记忆定义稍复杂。", "convertible": true, "correct_option": "d. equivalent points", "choice_question": "The space lattice is an abstraction derived from the ____ in the crystal structure.", "conversion_reason": "The original question is already in a multiple-choice format, which can be directly used as a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "atoms", "B": "ions", "C": "geometric points", "D": "equivalent points" }, "correct_answer": "D", "explanation": "The correct answer is D because a space lattice is derived from the periodic arrangement of equivalent points in the crystal structure, not the physical atoms or ions themselves. Option A and B exploit the cognitive bias of associating lattice points directly with physical particles. Option C is a professional intuition trap that seems mathematically correct but fails to capture the crystallographic requirement of equivalence between points.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3085, "question": "The reinforcing effect is best when the diameter of the fine particle phase in fine-grained composites is (1). A. $<0.01~\\\\mu\\\\mathrm{m}$ B.0.01\\\\~0.1-pm $\\\\mathrm{C.}>0.1\\\\mu m$", "answer": "(1)B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项A、B、C中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查对细粒复合材料中细颗粒相直径对增强效果影响的基础概念记忆，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于简单概念识别，直接记忆的难度等级。题目考察的是对细颗粒复合材料中细颗粒相直径范围的基础概念记忆，只需记住最佳增强效果的直径范围是0.01~0.1微米即可选择正确答案，无需复杂的理解或分析过程。", "convertible": true, "correct_option": "B.0.01\\~0.1-pm", "choice_question": "The reinforcing effect is best when the diameter of the fine particle phase in fine-grained composites is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When the dislocation pinning effect exceeds the grain boundary strengthening effect", "B": "When the Orowan strengthening mechanism becomes dominant over Hall-Petch strengthening", "C": "When the particle spacing matches the critical resolved shear stress", "D": "When the particle diameter is approximately equal to the Burgers vector magnitude" }, "correct_answer": "B", "explanation": "The correct answer is B because the transition from Hall-Petch to Orowan strengthening occurs when particles are too large for effective grain boundary pinning. Option A reverses the actual relationship between dislocation pinning and grain boundary effects. Option C sounds plausible but incorrectly mixes macroscopic stress concepts with microscopic spacing. Option D uses a fundamental parameter (Burgers vector) but misapplies it in this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 968, "question": "What is the structural model that constitutes a small-angle grain boundary?", "answer": "The structural model of a small-angle grain boundary is the dislocation model, for example, a symmetric tilt grain boundary is described by a set of parallel edge dislocations.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释小角度晶界的结构模型，答案提供了详细的文字描述和例子，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对小角度晶界结构模型的基本概念记忆和理解，属于定义和基本原理的记忆性知识。 | 难度: 该题目在选择题型中属于中等难度。虽然考察的是基础概念记忆（小角度晶界的结构模型），但需要考生不仅记住\"位错模型\"这一关键词，还要理解对称倾侧晶界与平行刃位错之间的关系。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。选择题型中，正确选项提供了具体示例，降低了纯粹记忆的难度，但仍需一定概念理解能力。", "convertible": true, "correct_option": "The dislocation model, for example, a symmetric tilt grain boundary is described by a set of parallel edge dislocations.", "choice_question": "What is the structural model that constitutes a small-angle grain boundary?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by providing the correct option and possibly other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dislocation model, where the boundary is described by an array of parallel edge dislocations", "B": "The coincident site lattice (CSL) model, where atoms at the boundary share lattice points from both crystals", "C": "The amorphous transition layer model, where the boundary consists of a disordered atomic arrangement", "D": "The vacancy aggregation model, where the boundary forms through clustering of point defects" }, "correct_answer": "A", "explanation": "The correct answer is A because small-angle grain boundaries (misorientation <15°) are well described by dislocation models, where the misorientation is accommodated by arrays of dislocations. Option B is incorrect because CSL models apply to high-angle grain boundaries. Option C exploits the common misconception that grain boundaries must be disordered, while Option D uses the plausible but incorrect idea that point defect aggregation could form boundaries.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3742, "question": "A 0.25-in.-diameter copper bar is to be cold worked 63%. Find the final diameter.", "answer": "the final diameter is 0.152 in.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解最终的直径，答案是一个具体的数值结果。 | 知识层次: 题目涉及基本的冷加工变形计算，只需要应用简单的公式和一步计算即可得出结果，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用冷加工变形的基本公式进行简单计算，无需多个步骤或公式组合。学生只需掌握单一公式并正确代入数值即可得出答案，属于最基础的难度等级。", "convertible": true, "correct_option": "0.152 in.", "choice_question": "A 0.25-in.-diameter copper bar is cold worked 63%. What is the final diameter?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.152 in.", "B": "0.183 in.", "C": "0.125 in.", "D": "0.217 in." }, "correct_answer": "A", "explanation": "正确答案A通过计算冷加工导致的面积减少得出。干扰项B利用常见错误计算路径（直接直径乘以冷加工百分比）。干扰项C利用直觉上认为63%减少应接近原始直径一半的认知偏差。干扰项D设计为反向计算错误（将剩余37%误认为加工后直径）。所有干扰项都针对AI可能出现的计算路径错误或概念混淆。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1291, "question": "When a crystal is subjected to external forces, the moving dislocations inside it will intersect, resulting in the formation of jogs and kinks. What is the length of these jogs and kinks the same as that of the intersecting dislocations?", "answer": "The magnitude of the Burgers vector", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和论述jogs和kinks的长度与Burgers矢量的关系，答案需要文字解释而非选择或判断 | 知识层次: 题目考查的是对位错运动中形成的jogs和kinks的基本概念的理解，特别是它们与Burgers矢量的关系。这属于基础概念的记忆和理解范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对基础概念（Burgers vector）的记忆，无需解释或分析。正确选项直接对应定义性知识，属于最简单的记忆性题目类型。", "convertible": true, "correct_option": "The magnitude of the Burgers vector", "choice_question": "When a crystal is subjected to external forces, the moving dislocations inside it will intersect, resulting in the formation of jogs and kinks. What is the length of these jogs and kinks the same as that of the intersecting dislocations?", "conversion_reason": "The answer is a standard term (the magnitude of the Burgers vector), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The magnitude of the Burgers vector", "B": "The mean free path of dislocations in the crystal", "C": "The interatomic spacing along the slip plane", "D": "The critical resolved shear stress for slip" }, "correct_answer": "A", "explanation": "The correct answer is A because the length of jogs and kinks formed by intersecting dislocations is fundamentally determined by the Burgers vector magnitude, which represents the atomic-scale displacement caused by a dislocation. Option B exploits the common misconception that dislocation interactions are governed by their mean free path. Option C uses the intuitive but incorrect association with atomic spacing. Option D introduces a completely unrelated but frequently discussed parameter in dislocation theory to create confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1690, "question": "How does the type of bonding affect the mechanical properties of materials?", "answer": "The type of bonding significantly affects the mechanical properties of materials. Crystals bonded by covalent, ionic, and metallic bonds are generally harder than those bonded by molecular forces. The greater the bond energy, the higher the elastic modulus. Materials with metallic bonds usually exhibit good plasticity, while those with ionic and covalent bonds (such as ceramics) are difficult to undergo plastic deformation and have poor plasticity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述不同类型的键合如何影响材料的机械性能，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释不同类型化学键对材料力学性能的影响，涉及多个概念（共价键、离子键、金属键、分子间力）的关联和综合分析，需要理解键能与弹性模量的关系以及不同键合类型对塑性变形能力的影响。虽然不涉及复杂计算，但需要对材料科学基本原理进行中等程度的综合应用和分析。 | 难度: 在选择题中属于较高难度，题目要求考生不仅理解不同类型化学键的基本概念，还需要综合分析它们对材料机械性能的具体影响。正确选项涉及多个知识点（共价键、离子键、金属键和分子间作用力）的比较，以及这些键能如何影响弹性模量和塑性变形能力。这需要考生能够进行多角度分析，将抽象的理论知识与具体的材料性能联系起来，属于中等应用层次中较复杂的综合分析题。", "convertible": true, "correct_option": "The type of bonding significantly affects the mechanical properties of materials. Crystals bonded by covalent, ionic, and metallic bonds are generally harder than those bonded by molecular forces. The greater the bond energy, the higher the elastic modulus. Materials with metallic bonds usually exhibit good plasticity, while those with ionic and covalent bonds (such as ceramics) are difficult to undergo plastic deformation and have poor plasticity.", "choice_question": "How does the type of bonding affect the mechanical properties of materials?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metallic bonds generally result in higher hardness than covalent bonds due to their delocalized electron structure", "B": "Ionic materials exhibit superior plasticity compared to metals because ion mobility enables dislocation movement", "C": "Covalent bonding leads to lower elastic modulus than metallic bonding due to directional bond characteristics", "D": "Van der Waals bonded materials show higher fracture toughness than metallic systems due to energy dissipation mechanisms" }, "correct_answer": "D", "explanation": "Correct answer (D) is counterintuitive but correct: Some van der Waals materials (like layered composites) can exhibit exceptional fracture toughness through unique energy dissipation mechanisms. Distractors: (A) reverses the typical hardness relationship (covalent > metallic), (B) incorrectly suggests ionic materials have better plasticity than metals (opposite of reality), (C) falsely claims covalent bonds have lower modulus (they typically have higher modulus due to strong directional bonds). These exploit common misconceptions about bond-property relationships.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 224, "question": "Using Na2CO3 and Na2SiO3 to dilute the same type of clay (mainly composed of kaolinite mineral) slurry, respectively, compare the differences in fluidity of the two slurries when the same amount of electrolyte is added.", "answer": "Adding Na2CO3 basically has no effect on the fluidity of the clay, while adding Na2SiO3 increases the fluidity of the slurry.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种电解质对粘土浆料流动性的影响，并解释其差异。答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求比较两种电解质对黏土浆料流动性的影响，需要理解电解质与黏土颗粒之间的相互作用机制，并能够分析不同电解质（Na2CO3和Na2SiO3）在相同条件下的不同效果。这涉及多步概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解电解质对粘土浆液流动性的影响，并比较Na2CO3和Na2SiO3的不同作用。题目涉及多个概念的综合分析，但选项提供了明确的对比结果，降低了部分难度。", "convertible": true, "correct_option": "Adding Na2CO3 basically has no effect on the fluidity of the clay, while adding Na2SiO3 increases the fluidity of the slurry.", "choice_question": "Using Na2CO3 and Na2SiO3 to dilute the same type of clay (mainly composed of kaolinite mineral) slurry, respectively, compare the differences in fluidity of the two slurries when the same amount of electrolyte is added.", "conversion_reason": "The answer is a clear and specific statement that can be directly used as a correct option in a multiple-choice question. The question can be reformatted to present this statement as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Na2CO3 increases fluidity more than Na2SiO3 due to stronger ionic dissociation", "B": "Both electrolytes decrease fluidity by compressing the double layer", "C": "Adding Na2CO3 has no effect while Na2SiO3 increases fluidity", "D": "Na2SiO3 decreases fluidity by forming silicate networks" }, "correct_answer": "C", "explanation": "Correct answer is C because Na2SiO3 dissociates into Na+ and SiO3^2- ions where the silicate anions adsorb on clay edges, creating negative charges that enhance repulsion and fluidity. Na2CO3's CO3^2- ions don't adsorb effectively on kaolinite. Option A exploits the common misconception about ionic strength effects. Option B reverses the actual behavior by assuming all electrolytes compress the double layer. Option D creates confusion with silicate polymerization effects that don't occur at these concentrations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1582, "question": "7. Deformation texture", "answer": "As the amount of plastic deformation increases, the phenomenon where a certain crystallographic orientation of different grains in a polycrystal tends to become consistent.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Deformation texture\"这一概念进行文字解释和论述，答案提供了详细的定义和现象描述，符合简答题的特征。 | 知识层次: 题目考查对\"变形织构\"这一基本概念的定义和现象描述，属于基础概念的记忆和理解范畴，不涉及应用或分析层面的要求。 | 难度: 在选择题型中，该题目属于概念解释和描述难度。虽然题目涉及变形织构的定义，但正确选项已经提供了较为详细的解释，考生只需理解并匹配这一描述即可。不需要进行复杂的分析或比较多个概念，因此属于中等难度。", "convertible": true, "correct_option": "As the amount of plastic deformation increases, the phenomenon where a certain crystallographic orientation of different grains in a polycrystal tends to become consistent.", "choice_question": "What is deformation texture?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "As the amount of plastic deformation increases, the phenomenon where a certain crystallographic orientation of different grains in a polycrystal tends to become consistent", "B": "The change in macroscopic texture caused by elastic deformation of crystalline materials under stress", "C": "The alignment of grain boundaries parallel to the deformation direction during plastic flow", "D": "The statistical distribution of grain sizes that develops during severe plastic deformation processes" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines deformation texture as the preferred crystallographic orientation development during plastic deformation. Option B is a cognitive bias trap, confusing plastic with elastic deformation which doesn't produce texture. Option C exploits professional intuition by incorrectly associating texture with grain boundary alignment. Option D is a multi-level verification trap, mixing texture with grain size distribution which is a separate phenomenon.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 140, "question": "The viscosity of Pyrex glass is 10^9 Pa·s at 1400℃ and 10^13 Pa·s at 840℃. What is the activation energy for viscous flow?", "answer": "According to the formula: η = η0 exp(ΔE / (R T)). At 1400℃, η = 10^9 Pa·s, T = 1400 + 273 = 1673 K, 10^9 = η0 exp(ΔE / (1673 × 8.314)). At 840℃, η = 10^13 Pa·s, T = 840 + 273 = 1113 K, 10^13 = η0 exp(ΔE / (1113 × 8.314)). Solving the two equations simultaneously yields: η0 = 11.22 Pa·s, ΔE = 254.62 kJ/mol.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的粘度和温度数据，应用阿伦尼乌斯公式进行数值计算，求解粘性流动的活化能。答案涉及公式推导和数值计算过程，符合计算题的特征。 | 知识层次: 题目需要应用阿伦尼乌斯公式进行多步计算，涉及温度转换、对数运算和联立方程求解，属于中等应用层次。虽然不涉及复杂的机理分析，但需要一定的综合分析能力和公式应用技巧。 | 难度: 在选择题中属于中等偏上难度，需要理解粘度与温度的关系公式，并进行多步计算和方程联立求解。虽然题目提供了具体数值，但解题过程涉及对数运算和单位转换，对学生的计算能力和概念理解有一定要求。", "convertible": true, "correct_option": "254.62 kJ/mol", "choice_question": "The viscosity of Pyrex glass is 10^9 Pa·s at 1400℃ and 10^13 Pa·s at 840℃. What is the activation energy for viscous flow?", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "254.62 kJ/mol", "B": "318.28 kJ/mol", "C": "187.45 kJ/mol", "D": "426.90 kJ/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (254.62 kJ/mol) calculated using the Arrhenius equation for viscosity. Option B (318.28 kJ/mol) is a cognitive bias trap that results from incorrectly converting Celsius to Kelvin. Option C (187.45 kJ/mol) exploits the common mistake of using natural log instead of base-10 log in the calculation. Option D (426.90 kJ/mol) is a professional intuition trap that mimics the activation energy for crystalline materials rather than glassy systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 509, "question": "Active oxygen", "answer": "Active oxygen: oxygen in silicate structures with partially unsaturated valence.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Active oxygen\"进行文字解释和论述，答案提供了概念的定义和特征描述，符合简答题的特点 | 知识层次: 题目考查对\"活性氧\"这一基本概念的定义记忆和理解，属于基础概念层次的知识点。 | 难度: 在选择题型中，该题目仅考察对\"活性氧\"这一基础概念的定义记忆，属于最基础的知识点掌握要求。正确选项直接给出了定义，无需任何解释或分析步骤，符合选择题型中最简单的难度等级。", "convertible": true, "correct_option": "oxygen in silicate structures with partially unsaturated valence", "choice_question": "Which of the following best describes active oxygen?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct option and plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "oxygen in silicate structures with partially unsaturated valence", "B": "oxygen radicals generated during polymer degradation", "C": "oxygen atoms participating in covalent bonding with transition metals", "D": "oxygen vacancies in oxide ceramics acting as charge carriers" }, "correct_answer": "A", "explanation": "The correct answer A describes active oxygen in the context of silicate chemistry where partially unsaturated valence states create reactive sites. Option B exploits the common association of 'active oxygen' with free radicals in polymer science. Option C creates confusion by referencing a valid but different concept of oxygen-metal bonding. Option D leverages the intuitive link between oxygen vacancies and activity in ceramics, which is incorrect in this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 508, "question": "Can magnesium oxide and aluminum oxide (solute) form a continuous solid solution? Explain the reason.", "answer": "They cannot form a continuous solid solution due to different crystal structures.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释镁氧化物和铝氧化物是否能形成连续固溶体，并说明原因。答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目需要理解固溶体的形成条件，并分析两种氧化物的晶体结构差异对固溶体形成的影响，涉及概念关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生不仅知道镁氧化物和铝氧化物的晶体结构不同，还需要理解这一差异如何影响它们形成连续固溶体的能力。这涉及到对晶体结构和固溶体形成条件的综合理解，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "They cannot form a continuous solid solution due to different crystal structures.", "choice_question": "Can magnesium oxide and aluminum oxide (solute) form a continuous solid solution?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because MgO has a rock salt structure while Al2O3 has a corundum structure", "B": "Yes, because both are oxides with similar ionic radii of Mg2+ and Al3+", "C": "No, because the valence difference between Mg2+ and Al3+ prevents substitution", "D": "Yes, but only at high temperatures where entropy dominates the free energy" }, "correct_answer": "A", "explanation": "The correct answer is A because continuous solid solutions require isostructural components. MgO (rock salt) and Al2O3 (corundum) have fundamentally different crystal structures. Option B exploits the ionic radius similarity bias but ignores structural requirements. Option C uses a partially correct but irrelevant factor (valence difference). Option D creates a thermodynamic plausibility trap by invoking high-temperature entropy effects that cannot overcome structural incompatibility.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1311, "question": "Homogeneous nucleation of crystal nuclei relies on (5) providing atomic clusters with $r>r^{*}$ to act as nuclei.", "answer": "Structural fluctuations", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释晶体核均匀成核的机制，答案需要文字描述结构波动的作用，属于简答题类型 | 知识层次: 题目考查均相成核的基本概念，特别是结构波动在成核过程中的作用，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解\"结构波动\"（Structural fluctuations）在晶体成核过程中的作用，并能够将其与题目描述的情境联系起来。这超出了简单的定义记忆，需要对概念有一定的理解和应用能力。", "convertible": true, "correct_option": "Structural fluctuations", "choice_question": "Homogeneous nucleation of crystal nuclei relies on which of the following providing atomic clusters with $r>r^{*}$ to act as nuclei?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Structural fluctuations", "B": "Thermal conductivity gradients", "C": "Dislocation pile-up stresses", "D": "External electromagnetic fields" }, "correct_answer": "A", "explanation": "The correct answer is A because homogeneous nucleation fundamentally relies on random structural fluctuations in the melt to form critical nuclei. Option B exploits the common misconception that temperature gradients drive nucleation. Option C targets confusion between homogeneous and heterogeneous nucleation mechanisms. Option D appeals to the intuition that external fields might influence nucleation, but this would make the process heterogeneous.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3080, "question": "When designing fiber-reinforced composites, for a matrix with lower toughness, the coefficient of expansion of the fiber can be what? A. Slightly lower B. Very different C. Slightly higher D. The same", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从选项A、B、C、D中选择正确答案 | 知识层次: 题目涉及复合材料设计中纤维与基体热膨胀系数的匹配问题，需要理解材料性能之间的相互作用关系，并做出适当选择。这属于中等应用层次，需要将材料性能知识应用于具体设计情境中，但不需要复杂的计算或深度分析。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅理解纤维增强复合材料的基本概念，还需要掌握基体韧性与纤维膨胀系数之间的复杂关系。解题过程需要综合分析材料性能的匹配原则，并判断在特定条件下（基体韧性较低时）纤维膨胀系数的合理选择。这超出了简单记忆或单一概念应用的范畴，属于需要多步推理和综合分析的选择题。", "convertible": true, "correct_option": "C", "choice_question": "When designing fiber-reinforced composites, for a matrix with lower toughness, the coefficient of expansion of the fiber can be what?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The fiber's thermal conductivity must match the matrix exactly", "B": "The fiber should have significantly higher fracture toughness than the matrix", "C": "The fiber's coefficient of thermal expansion should be slightly higher than the matrix", "D": "The fiber's elastic modulus must be at least 50% lower than the matrix" }, "correct_answer": "C", "explanation": "For a matrix with lower toughness, slightly higher CTE in the fiber creates beneficial compressive stresses that inhibit crack propagation. Option A is wrong because thermal conductivity matching is irrelevant for toughness. Option B is a cognitive bias trap - while higher toughness seems logical, it actually creates dangerous stress concentrations. Option D exploits modulus confusion - lower modulus fibers would reduce composite stiffness without improving toughness.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4424, "question": "What influence does the presence of alloying elements (other than carbon) have on the shape of a herdenability curve? Briefly explain this effect.", "answer": "The presence of alloying elements (other than carbon) causes a much more gradual decrease in hardness with position from the quenched end for a hardenability curve. The reason for this effect is that alloying elements retard the formation of pearlitic and bainitic structures which are not as hard as martensite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释合金元素对淬透性曲线形状的影响，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释合金元素对淬透性曲线形状的影响，并简要说明这种效应的原因。这需要综合运用材料科学中的相变理论、合金元素的作用机制以及淬透性曲线的理解，进行推理分析和机理解释。涉及的知识点较为复杂，且需要将多个概念关联起来进行综合分析。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The presence of alloying elements (other than carbon) causes a much more gradual decrease in hardness with position from the quenched end for a hardenability curve. The reason for this effect is that alloying elements retard the formation of pearlitic and bainitic structures which are not as hard as martensite.", "choice_question": "What influence does the presence of alloying elements (other than carbon) have on the shape of a hardenability curve?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Alloying elements create a steeper hardness drop-off due to enhanced thermal conductivity during quenching", "B": "The curve becomes more linear as alloying elements reduce the temperature dependence of phase transformations", "C": "Alloying elements cause multiple inflection points in the curve due to competing precipitation mechanisms", "D": "Alloying elements produce a more gradual hardness decrease by retarding non-martensitic transformations" }, "correct_answer": "D", "explanation": "The correct answer is D because alloying elements (other than carbon) retard the formation of pearlite and bainite, allowing more martensite to form at greater distances from the quenched end, resulting in a more gradual hardness decrease. Option A is incorrect because it confuses thermal conductivity with transformation kinetics. Option B is a cognitive trap suggesting oversimplified linear behavior. Option C exploits the intuition about precipitation but is irrelevant to hardenability curves.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3155, "question": "Determine the crystallographic direction in the diamond structure defined by the points (0,0,0) and $(\\\\frac{3}{4},\\\\frac{3}{4},\\\\frac{1}{4})$, and find the crystallographic plane perpendicular to this direction.", "answer": "Subtract the coordinates of the two points, then reduce them to a set of coprime integers. The direction indices are [331]. Since it is a cubic system, the crystallographic plane with the same indices is perpendicular to the direction, i.e., (331) is perpendicular to [331].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来确定晶体学方向和垂直的晶面，解答过程涉及坐标计算和指数简化，需要详细的步骤说明而非简单的选择或判断。 | 知识层次: 题目需要多步计算（坐标相减、约简为互质整数）和概念关联（立方晶系中方向与垂直晶面的关系），属于中等应用层次。虽然不涉及复杂的综合分析或创新设计，但比简单应用要求更高。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求确定金刚石结构中的晶向，并找到与之垂直的晶面。解题步骤包括坐标减法、约简到互质整数，以及利用立方晶系的性质确定垂直晶面。虽然步骤较多，但在选择题型中，正确选项提供了明确的解题思路和答案，降低了部分难度。", "convertible": true, "correct_option": "[331]", "choice_question": "Determine the crystallographic direction in the diamond structure defined by the points (0,0,0) and $(\\frac{3}{4},\\frac{3}{4},\\frac{1}{4})$. Which of the following is the correct crystallographic direction?", "conversion_reason": "The answer is a standard crystallographic direction index, which can be presented as a clear and distinct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[331]", "B": "[111]", "C": "[110]", "D": "[311]" }, "correct_answer": "A", "explanation": "The correct crystallographic direction is [331], obtained by multiplying the fractional coordinates (3/4, 3/4, 1/4) by 4 to eliminate fractions. Option B [111] is a common face diagonal in diamond structure, exploiting the AI's tendency to default to simple high-symmetry directions. Option C [110] is a frequent slip direction in FCC metals, playing on material system confusion. Option D [311] is numerically close but incorrect, targeting rounding errors in AI calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 723, "question": "For some materials, no matter how fast the cooling rate is, it is impossible to form a glass", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（×表示错误），符合判断题的特征 | 知识层次: 题目考查对材料科学中玻璃形成能力的基本概念的理解，涉及冷却速率与玻璃形成之间的关系，属于基础概念的记忆和简单判断。 | 难度: 该题目属于基础概念正误判断题，仅需记忆材料科学中关于玻璃形成的基本原理即可作答。在选择题型中，这类题目仅需识别正确选项，不涉及复杂概念理解或分析过程，属于最简单的难度等级。", "convertible": true, "correct_option": "×", "choice_question": "For some materials, no matter how fast the cooling rate is, it is impossible to form a glass", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All metallic materials can form amorphous structures if cooled rapidly enough from the liquid state.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many metallic alloys can form amorphous structures with sufficiently rapid cooling (bulk metallic glasses), pure metals generally cannot form amorphous structures regardless of cooling rate due to their simple atomic structure and high crystallization tendency. This statement is false because it makes an absolute claim that applies to all metallic materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3776, "question": "Based on Hume-Rothery's conditions, would the system Au-Ag be expected to display unlimited solid solubility? Explain.", "answer": "Yes", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求基于Hume-Rothery条件进行解释说明，答案需要文字论述而非简单选择或判断 | 知识层次: 题目要求基于Hume-Rothery规则分析Au-Ag体系的固溶度问题，需要理解并应用多个条件（原子尺寸、电负性、价电子数、晶体结构）进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解Hume-Rothery规则中的多个条件（如原子尺寸差、电负性、价电子浓度和晶体结构），并将这些概念应用于Au-Ag系统进行综合分析。虽然题目给出了正确选项，但学生仍需掌握这些概念并能够进行关联分析才能正确回答。", "convertible": true, "correct_option": "Yes", "choice_question": "Based on Hume-Rothery's conditions, would the system Au-Ag be expected to display unlimited solid solubility?", "conversion_reason": "The answer is a standard term (Yes/No), which can be converted into a multiple-choice question format with 'Yes' as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, due to identical crystal structures and similar atomic radii", "B": "No, because their electronegativity difference exceeds 0.4", "C": "Only at high temperatures due to thermal expansion effects", "D": "No, because gold's d-electron configuration prevents complete solubility" }, "correct_answer": "A", "explanation": "Correct answer is A because Au-Ag system meets all Hume-Rothery conditions: 1) identical FCC crystal structures, 2) atomic radius difference <15% (Au:1.44Å, Ag:1.45Å), 3) similar electronegativity (Au:2.54, Ag:1.93), and 4) same valence. Option B is a cognitive bias trap - while their electronegativity difference is 0.61, it's still within acceptable range for solid solubility. Option C exploits thermal intuition but ignores that solubility exists at all temperatures. Option D uses a sophisticated-sounding but irrelevant d-electron argument that doesn't apply to noble metals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4808, "question": "Give the approximate temperature at which creep deformation becomes an important consideration for molybdenum.", "answer": "for mo, 776°c or 1429°f.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从选项中选择或判断对错，也不需要复杂的计算过程。答案是一个具体的数值，属于简答形式。 | 知识层次: 题目考查对特定材料（钼）的蠕变变形温度的记忆，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆特定材料（钼）的蠕变温度这一基础数据，属于单一事实性知识的直接回忆。不需要概念解释或复杂分析，完全符合等级1\"基本定义简答\"的标准。选择题型中此类直接考查记忆点的题目属于最低难度层级。", "convertible": true, "correct_option": "776°C or 1429°F", "choice_question": "At what approximate temperature does creep deformation become an important consideration for molybdenum?", "conversion_reason": "The answer is a specific temperature value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "776°C (1429°F)", "B": "1200°C (2192°F)", "C": "500°C (932°F)", "D": "0.4 × melting temperature (1316°C)" }, "correct_answer": "A", "explanation": "The correct answer is A because creep deformation in molybdenum typically becomes significant at approximately 0.3-0.4 of its melting temperature (2617°C), which corresponds to 776°C. Option B is a cognitive bias trap using the recrystallization temperature of tungsten (a common analog material). Option C exploits elastic/plastic transition confusion by using the temperature where yield strength starts decreasing. Option D is a multi-level verification trap using the correct ratio but applying it to absolute melting point instead of Kelvin scale.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 626, "question": "Explain the effect of grain boundaries on material deformation", "answer": "Grain boundaries strengthen metal materials at room temperature but weaken them at high temperatures.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释晶界对材料变形的影响，需要文字解释和论述，答案也提供了详细的解释而非简单的选择或判断。 | 知识层次: 题目要求解释晶界对材料变形的影响，涉及不同温度条件下的行为差异，需要综合运用材料科学中的晶界理论、变形机制以及温度效应等多方面知识进行推理分析。这超出了简单记忆或直接应用的范围，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。理由如下：", "convertible": true, "correct_option": "Grain boundaries strengthen metal materials at room temperature but weaken them at high temperatures.", "choice_question": "Which of the following describes the effect of grain boundaries on material deformation?", "conversion_reason": "The answer is a standard statement that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain boundaries strengthen metal materials at room temperature but weaken them at high temperatures", "B": "Grain boundaries always increase material hardness regardless of temperature due to dislocation pinning", "C": "Grain boundaries reduce yield strength by providing easy paths for dislocation movement", "D": "Grain boundaries have negligible effect on deformation as most dislocations occur within grains" }, "correct_answer": "A", "explanation": "Correct answer A captures the dual role of grain boundaries: at room temperature they impede dislocation motion (strengthening), while at high temperatures they facilitate grain boundary sliding (weakening). Option B is a common oversimplification ignoring temperature effects. Option C reverses the actual room-temperature mechanism. Option D underestimates grain boundaries' role by focusing only on intragranular dislocations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3336, "question": "Determine the heat treatment conditions (temperature, time, cooling rate, etc.) for normalizing φ25 hot-rolled eutectoid steel.", "answer": "Normalizing: 780°C holding for 1h, air cooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求确定热处理条件（温度、时间、冷却速率等），答案需要文字解释和论述，而不是从选项中选择或简单的对错判断或数值计算。 | 知识层次: 题目要求根据给定的材料（φ25热轧共析钢）直接应用标准的热处理工艺（正火），涉及温度、时间和冷却方式等具体参数的记忆和应用，属于直接套用标准工艺的简单应用层次。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接套用标准热处理工艺参数（780°C保温1小时空冷）即可作答。不需要进行计算或复杂分析，属于对基础知识的直接应用，符合等级2\"简单应用过程描述\"的特征。", "convertible": true, "correct_option": "Normalizing: 780°C holding for 1h, air cooling.", "choice_question": "What are the heat treatment conditions (temperature, time, cooling rate, etc.) for normalizing φ25 hot-rolled eutectoid steel?", "conversion_reason": "The answer is a standard and specific set of conditions, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "780°C holding for 1h, air cooling", "B": "850°C holding for 30min, furnace cooling", "C": "720°C holding for 2h, water quenching", "D": "900°C holding for 15min, air cooling" }, "correct_answer": "A", "explanation": "Correct answer A follows standard normalizing practice for eutectoid steel: temperature slightly above A3 (780°C), sufficient time for austenitization (1h), and air cooling to achieve fine pearlite. Option B is wrong because furnace cooling would produce coarse pearlite (annealing). Option C is incorrect as 720°C is below A1 and water quenching would produce martensite. Option D's high temperature risks grain growth despite air cooling.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2100, "question": "A carbon steel, under equilibrium cooling conditions, obtains a microstructure consisting of 50% pearlite and 50% ferrite. Question: If this alloy is heated to 730°C, what microstructure will be obtained under equilibrium conditions?", "answer": "The microstructure will be F+A", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释在特定温度下材料的微观结构变化，答案需要文字描述（F+A表示铁素体和奥氏体的混合结构），属于需要文字解释和论述的简答题类型。 | 知识层次: 题目需要理解铁碳相图并应用相变知识，分析在特定温度下的平衡相组成，涉及多步概念关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解铁碳相图的基本概念，能够分析不同温度下的相变过程，并进行多步计算和概念关联。虽然题目给出了明确的温度点，但需要考生综合运用相图知识和平衡冷却条件来推断最终的微观结构。", "convertible": true, "correct_option": "F+A", "choice_question": "A carbon steel, under equilibrium cooling conditions, obtains a microstructure consisting of 50% pearlite and 50% ferrite. If this alloy is heated to 730°C, what microstructure will be obtained under equilibrium conditions?", "conversion_reason": "The answer is a standard term (F+A) which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Austenite + Ferrite (F+A)", "B": "100% Austenite", "C": "Pearlite + Austenite", "D": "Ferrite + Cementite" }, "correct_answer": "A", "explanation": "The correct answer is A because at 730°C (just below the eutectoid temperature), the equilibrium microstructure for a steel with 50% pearlite composition would be a mixture of austenite and ferrite. Option B is incorrect because complete austenitization requires higher temperatures. Option C is a common misconception where students confuse heating with cooling transformations. Option D represents room temperature equilibrium structure, exploiting temperature condition oversight.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4584, "question": "Some metal alloy is known to have electrical conductivity and electron mobility values of 1.5 × 10^{7} (\\Omega·m)^{-1} and 0.0020{m}^{2} / V·s, respectively. Through a specimen of this alloy that is 35mm thick is passed a current of 45 A. What magnetic field would need to be imposed to yield a Hall voltage of -1.0 × 10^{-7}V ?", "answer": "the required magnetic field is 0.58 \\mathrm{tesla}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解所需的磁场强度，答案是一个具体的数值结果（0.58 tesla），符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要综合运用电导率、电子迁移率、电流密度和霍尔效应等知识，通过公式推导和数值计算得出结果，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要综合运用电导率、电子迁移率、霍尔效应等多个物理概念，并进行多步骤计算。虽然题目提供了正确选项，但解题过程涉及多个公式转换和单位换算（如厚度单位转换），需要较强的综合分析能力。相比单纯的概念选择题，这类计算型选择题对知识掌握深度和计算准确性要求更高。", "convertible": true, "correct_option": "0.58 tesla", "choice_question": "Some metal alloy is known to have electrical conductivity and electron mobility values of 1.5 × 10^{7} (Ω·m)^{-1} and 0.0020 m^{2}/V·s, respectively. Through a specimen of this alloy that is 35 mm thick is passed a current of 45 A. What magnetic field would need to be imposed to yield a Hall voltage of -1.0 × 10^{-7} V?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.58 tesla", "B": "1.16 tesla", "C": "0.29 tesla", "D": "2.32 tesla" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Hall effect equation: B = V_H * σ / (I * μ_e), where V_H is Hall voltage, σ is conductivity, I is current, and μ_e is electron mobility. Plugging in the values gives B = (-1.0 × 10^-7) * (1.5 × 10^7) / (45 * 0.0020) = 0.58 tesla. Option B doubles the correct value, exploiting a common calculation error of missing the negative sign in Hall voltage. Option C halves the correct value, targeting those who might confuse thickness with relevant dimensions. Option D quadruples the correct value, preying on unit conversion errors between mm and m for thickness.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3129, "question": "Explain the basic concept and terminology: dendritic segregation", "answer": "Dendritic segregation: During non-equilibrium solidification, the initially solidified solid solution contains more high-melting-point components, while the later solidified solid solution contains more low-melting-point components. This results in non-uniform chemical composition within the grain, known as intracrystalline segregation. Since solid solutions often grow in a dendritic manner, it is also called dendritic segregation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释基本概念和术语，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即dendritic segregation的定义和基本原理，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目要求考生解释并描述\"dendritic segregation\"的基本概念和术语，涉及非平衡凝固过程中的成分不均匀现象。虽然需要理解多个相关概念（如非平衡凝固、固溶体、高/低熔点组分等），但主要考察的是对单一概念的定义和基本描述，不需要进行复杂的比较分析或推导。因此属于选择题型中的中等难度（等级2）。", "convertible": true, "correct_option": "Dendritic segregation: During non-equilibrium solidification, the initially solidified solid solution contains more high-melting-point components, while the later solidified solid solution contains more low-melting-point components. This results in non-uniform chemical composition within the grain, known as intracrystalline segregation. Since solid solutions often grow in a dendritic manner, it is also called dendritic segregation.", "choice_question": "下列关于 dendritic segregation 的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dendritic segregation occurs due to non-equilibrium solidification where high-melting-point components solidify first, creating intracrystalline composition gradients", "B": "Dendritic segregation is a surface phenomenon caused by preferential diffusion of solute atoms along grain boundaries during annealing", "C": "Dendritic segregation results from equilibrium solidification where solute atoms uniformly distribute between dendrite arms to minimize free energy", "D": "Dendritic segregation refers to the macroscopic composition variation caused by convection currents in the molten metal before solidification" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the non-equilibrium nature of dendritic segregation and its characteristic intracrystalline composition gradient. Option B incorrectly associates it with grain boundary diffusion (a common confusion with boundary segregation). Option C wrongly assumes equilibrium conditions (a tempting error since many segregation phenomena are equilibrium-based). Option D conflates dendritic segregation with macrosegregation (a frequent conceptual overlap mistake in solidification studies).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1350, "question": "Analyze the essential similarities between work hardening, fine grain strengthening, solid solution strengthening, and second-phase strengthening", "answer": "Similarities: All involve hindering dislocation movement, increasing the resistance to dislocation glide, thereby strengthening the material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析四种强化机制的相似性，需要文字解释和论述，答案也是以文字形式给出，符合简答题的特征。 | 知识层次: 题目要求分析四种强化机制的相似性，涉及对位错运动阻碍机理的综合理解和比较分析，需要深入理解材料强化机制的本质，并进行概念间的关联和推理分析。这超出了简单记忆或基本应用层次，属于需要综合运用知识进行复杂分析的范畴。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求分析四种强化机制的相似性，涉及多个复杂概念的综合运用和机理解释。正确选项需要深入理解位错运动受阻的共同本质，并能够将不同强化机制的微观机理联系起来。这种题目不仅考察知识点的记忆，更要求考生具备高阶的分析推理能力，能够从不同现象中抽象出共同规律，属于复杂现象全面分析的层次。", "convertible": true, "correct_option": "All involve hindering dislocation movement, increasing the resistance to dislocation glide, thereby strengthening the material.", "choice_question": "What is the essential similarity between work hardening, fine grain strengthening, solid solution strengthening, and second-phase strengthening?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "All involve hindering dislocation movement, increasing the resistance to dislocation glide", "B": "All increase the elastic modulus of the material by altering atomic bonding", "C": "All rely on introducing phase boundaries to block dislocation propagation", "D": "All primarily affect the material's thermal conductivity rather than mechanical properties" }, "correct_answer": "A", "explanation": "Correct answer A identifies the fundamental mechanism shared by all four strengthening methods - impeding dislocation motion. Option B exploits confusion between strengthening mechanisms and elastic modulus (a material constant). Option C is partially correct but only applies to second-phase strengthening. Option D is a complete red herring targeting AI's tendency to associate multiple concepts with thermal properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 925, "question": "Briefly describe the characteristics of the eutectic reaction in a binary system and calculate the degrees of freedom when its phases are in equilibrium.", "answer": "The eutectic reaction is: the liquid phase simultaneously solidifies into two solid phases of different compositions, which grow cooperatively and generally form a lamellar structure. When the eutectic reaction occurs, the degrees of freedom are 0, meaning the compositions of the three phases are fixed, and the temperature is also fixed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求简要描述共晶反应的特征并计算自由度，答案包含文字解释和论述，没有涉及选项选择、判断对错或复杂计算。 | 知识层次: 题目不仅要求描述共晶反应的基本特征（基础概念记忆），还需要计算自由度（简单应用），并将两者结合起来进行综合分析。这涉及到多步思维过程和对相平衡概念的理解，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握共晶反应的基本特征，并能计算自由度，涉及多步计算和概念关联。虽然题目提供了正确选项，但考生仍需具备综合分析能力才能准确理解并选择正确答案。", "convertible": true, "correct_option": "The eutectic reaction is: the liquid phase simultaneously solidifies into two solid phases of different compositions, which grow cooperatively and generally form a lamellar structure. When the eutectic reaction occurs, the degrees of freedom are 0, meaning the compositions of the three phases are fixed, and the temperature is also fixed.", "choice_question": "Which of the following correctly describes the characteristics of the eutectic reaction in a binary system and the degrees of freedom when its phases are in equilibrium?", "conversion_reason": "The answer is a standard description of the eutectic reaction and includes a specific calculation (degrees of freedom = 0), making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The eutectic reaction involves simultaneous solidification of liquid into two solid phases with fixed compositions at a constant temperature (F=0)", "B": "The eutectic reaction is a gradual transformation where liquid changes composition continuously until forming two solids (F=1)", "C": "The eutectic reaction occurs at variable compositions where liquid transforms into two solids with adjustable phase fractions (F=2)", "D": "The eutectic reaction requires external pressure to maintain three-phase equilibrium (F=1 at constant pressure)" }, "correct_answer": "A", "explanation": "The correct answer A describes the key features: invariant reaction (F=0), fixed compositions, and cooperative growth. Option B incorrectly suggests gradual transformation and wrong degrees of freedom. Option C falsely implies composition variability. Option D introduces non-existent pressure dependence. Advanced AIs might select B due to its gradual-change narrative or D due to overcomplicating the equilibrium condition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 957, "question": "Briefly describe metallic bond", "answer": "The bonding force generated by the electrostatic interaction between free electrons and atomic nuclei.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述金属键，答案是一段文字解释，属于需要文字论述的简答题类型 | 知识层次: 题目考查金属键的基本定义和原理，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目仅要求对金属键的基本定义进行简答，属于基础概念的记忆性知识。题目直接给出了正确选项，无需复杂的分析或推理过程，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "The bonding force generated by the electrostatic interaction between free electrons and atomic nuclei.", "choice_question": "Which of the following best describes a metallic bond?", "conversion_reason": "The answer is a standard definition of a metallic bond, which can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The bonding force generated by the electrostatic interaction between free electrons and atomic nuclei", "B": "The covalent sharing of valence electrons between adjacent metal atoms", "C": "The directional bonding formed by overlapping d-orbitals in transition metals", "D": "The secondary bonding caused by temporary dipole moments in metal lattices" }, "correct_answer": "A", "explanation": "Option A correctly describes metallic bonding as the non-directional electrostatic attraction between delocalized electrons and positively charged nuclei. Option B incorrectly applies covalent bonding characteristics to metals. Option C describes a specific case of hybridized bonding in some transition metals but is not the general definition. Option D falsely attributes metallic bonding to van der Waals forces, which are much weaker secondary bonds.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3052, "question": "The porosity of ordinary ceramics is (2). A.5%~10% B.<5% C.<0.5% D.>10%", "answer": "(2)A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查普通陶瓷孔隙率的基本概念记忆，属于定义性知识的直接回忆，无需复杂分析或计算。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需直接回忆普通陶瓷的孔隙率范围即可选出正确答案，无需复杂理解或分析步骤。", "convertible": true, "correct_option": "A.5%~10%", "choice_question": "The porosity of ordinary ceramics is", "conversion_reason": "原题目已经是单选题格式，可以直接转换。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship holds for grain sizes below 100nm", "B": "Dislocation motion becomes easier when grain size decreases below 1μm", "C": "Nanocrystalline materials always exhibit higher strength than coarse-grained counterparts", "D": "Grain boundary sliding dominates deformation at all nanocrystalline scales" }, "correct_answer": "A", "explanation": "The Hall-Petch relationship describes the increase in yield strength with decreasing grain size, but it breaks down below a critical grain size (typically around 10-100nm). Option A is correct because it specifies the upper limit where the relationship still holds. Option B exploits the common misconception that smaller grains always mean easier dislocation motion, ignoring the complex behavior at nanoscales. Option C uses an absolute statement ('always') which is false due to possible inverse Hall-Petch effects. Option D creates confusion by suggesting a single dominant mechanism across all nanocrystalline scales, while in reality different mechanisms dominate at different size ranges.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1103, "question": "A metal test bar with a length of 20cm and a cross-sectional area of 4cm² is fixed at the upper end, and a tensile force of 980N is applied at the lower end. Calculate the normal stress and shear stress on a plane that forms a 0° angle with the central axis of the metal test bar.", "answer": "When θ=0°: normal stress σθ=0; shear stress τθ=0.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，具体涉及计算法向应力和剪切应力。答案给出了具体的计算结果，符合计算题的特征。 | 知识层次: 题目要求进行基本的应力计算，直接应用公式即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算特定角度下的正应力和剪应力，直接套用基本公式即可得出结果，无需复杂推导或多步骤计算。正确选项直接给出了计算结果，考察的是对基本概念和公式的简单应用能力。", "convertible": true, "correct_option": "normal stress σθ=0; shear stress τθ=0", "choice_question": "A metal test bar with a length of 20cm and a cross-sectional area of 4cm² is fixed at the upper end, and a tensile force of 980N is applied at the lower end. What are the normal stress and shear stress on a plane that forms a 0° angle with the central axis of the metal test bar?", "conversion_reason": "The answer is a specific and deterministic result, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "normal stress σθ=0; shear stress τθ=0", "B": "normal stress σθ=245MPa; shear stress τθ=0", "C": "normal stress σθ=0; shear stress τθ=245MPa", "D": "normal stress σθ=245MPa; shear stress τθ=245MPa" }, "correct_answer": "A", "explanation": "The correct answer is A because at 0° angle, the plane is parallel to the applied force, resulting in no normal or shear stress. Option B incorrectly calculates normal stress without considering the angle. Option C mistakenly assumes shear stress exists at 0°. Option D combines both errors, calculating stresses as if the plane were perpendicular to the force.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4291, "question": "Estimate the theoretical fracture strength of a brittle material if it is known that fracture occurs by the propagation of an elliptically shaped surface crack of length 0.25 mm(0.01 in.) and having a tip radius of curvature of 1.2 × 10^{-3} mm\\left(4.7 × 10^{-5} in\\right..) when a stress of 1200 MPa(174,000 psi) is applied.", "answer": "the theoretical fracture strength is 3.5 × 10^{4} MPa (5.1 × 10^{6} psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计脆性材料的理论断裂强度，答案是一个具体的数值结果，解答过程需要运用相关公式进行计算。 | 知识层次: 题目需要进行多步计算，涉及断裂力学中的应力集中公式应用，需要理解裂纹几何参数与应力强度之间的关系，并进行数值计算。虽然不涉及复杂的综合分析或创新应用，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解断裂力学的基本概念（如应力集中因子、裂纹尖端半径的影响），并应用相关公式进行多步计算。题目涉及单位转换和复杂数学运算，但作为选择题，正确选项的存在降低了部分难度，因为不需要完全推导过程。", "convertible": true, "correct_option": "3.5 × 10^{4} MPa (5.1 × 10^{6} psi)", "choice_question": "Estimate the theoretical fracture strength of a brittle material if it is known that fracture occurs by the propagation of an elliptically shaped surface crack of length 0.25 mm(0.01 in.) and having a tip radius of curvature of 1.2 × 10^{-3} mm(4.7 × 10^{-5} in.) when a stress of 1200 MPa(174,000 psi) is applied. The theoretical fracture strength is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.5 × 10^4 MPa (5.1 × 10^6 psi)", "B": "1.2 × 10^3 MPa (1.74 × 10^5 psi)", "C": "8.9 × 10^4 MPa (1.29 × 10^7 psi)", "D": "2.4 × 10^3 MPa (3.48 × 10^5 psi)" }, "correct_answer": "A", "explanation": "正确答案A是通过Griffith理论计算得出的理论断裂强度，考虑了裂纹尖端应力集中效应。干扰项B直接使用了题目中给出的外加应力值，这是典型的'第一印象'陷阱。干扰项C故意放大了应力集中系数，利用了计算过程中可能出现的数量级错误。干扰项D则是将外加应力乘以2，模拟了常见的简单线性外推错误。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1012, "question": "What are the characterization methods for dislocation density?", "answer": "There are two methods: volume density, which is the length of dislocation lines per unit volume; and surface density, which is the number of dislocation lines perpendicularly passing through a unit area.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述位错密度的表征方法，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对位错密度表征方法的基本概念记忆和理解，仅需回答两种方法的定义，不涉及应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生记忆并理解位错密度的两种表征方法（体积密度和表面密度）的定义，但不需要进行复杂的比较分析或推导。虽然涉及两个概念，但都属于基础概念记忆层次，解题步骤相对简单，只需正确识别和匹配定义即可。", "convertible": true, "correct_option": "There are two methods: volume density, which is the length of dislocation lines per unit volume; and surface density, which is the number of dislocation lines perpendicularly passing through a unit area.", "choice_question": "Which of the following are the characterization methods for dislocation density?", "conversion_reason": "The answer is a standard description of the methods, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Volume density (length of dislocation lines per unit volume) and surface density (number of dislocation lines perpendicularly passing through a unit area)", "B": "X-ray diffraction peak broadening and transmission electron microscopy (TEM) direct observation", "C": "Resistivity measurements and hardness testing", "D": "Optical microscopy grain size analysis and scanning electron microscopy (SEM) surface topography" }, "correct_answer": "A", "explanation": "The correct answer is A because these are the two fundamental methods for quantifying dislocation density. Option B uses characterization techniques that can estimate dislocation density but are not the definition of the methods themselves (cognitive bias). Option C employs material properties affected by dislocations but don't directly measure density (intuition trap). Option D uses unrelated microstructure characterization methods that don't measure dislocations (multi-level verification trap). Advanced AIs might incorrectly select B due to its technical accuracy in estimation methods rather than fundamental definitions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3977, "question": "During the recovery of a cold-worked material, is there a significant reduction in the number of dislocations, to approximately the number found in the precold-worked state?", "answer": "There is not a significant reduction in the number of dislocations, to approximately the number found in the precold-worked state.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性，答案直接给出了对陈述的判断（否定），符合判断题的特征。 | 知识层次: 题目考查对冷加工材料恢复过程中位错数量变化的基本概念的理解和记忆，属于基础概念层次。 | 难度: 该题目属于基础概念记忆层次，仅需判断关于冷加工材料恢复过程中位错数量变化的基本陈述是否正确。题目直接考察对恢复过程定义的理解，无需复杂推理或概念间的比较分析，属于选择题型中最简单的正误判断类型。", "convertible": true, "correct_option": "There is not a significant reduction in the number of dislocations, to approximately the number found in the precold-worked state.", "choice_question": "During the recovery of a cold-worked material, is there a significant reduction in the number of dislocations, to approximately the number found in the precold-worked state?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "During the recovery of a cold-worked material, is there a significant reduction in the number of dislocations, to approximately the number found in the precold-worked state?", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "During recovery, dislocations rearrange into lower-energy configurations (polygonization) but the total number remains similar to the cold-worked state. Significant dislocation reduction only occurs during recrystallization, not recovery. A common misconception is equating recovery with complete dislocation annihilation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1935, "question": "How to distinguish between hot deformation and cold deformation of metals?", "answer": "It is distinguished based on the relationship between the deformation temperature and the recrystallization temperature. Deformation above the recrystallization temperature is hot deformation, and vice versa is cold deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释如何区分金属的热变形和冷变形，答案提供了文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目考查对金属热变形和冷变形的基本定义和分类的记忆和理解，涉及基本原理的简单应用，但不需要复杂的分析或综合。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即区分热变形和冷变形的标准。正确选项直接给出了定义和分类，无需复杂的分析或推理步骤，属于最基础的难度等级。", "convertible": true, "correct_option": "It is distinguished based on the relationship between the deformation temperature and the recrystallization temperature. Deformation above the recrystallization temperature is hot deformation, and vice versa is cold deformation.", "choice_question": "How is hot deformation distinguished from cold deformation of metals?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Based on whether the deformation temperature is above or below the recrystallization temperature", "B": "Based on whether the deformation causes permanent dislocation movement or only elastic deformation", "C": "Based on whether the deformation occurs above or below 0.5 times the melting temperature (in Kelvin)", "D": "Based on whether the deformation process includes dynamic recovery mechanisms" }, "correct_answer": "A", "explanation": "The correct answer is A because hot deformation is fundamentally defined by occurring above the recrystallization temperature, allowing simultaneous deformation and recrystallization. Option B is a cognitive bias trap - while dislocation movement is involved, it's not the distinguishing factor. Option C is a professional intuition trap - while 0.5Tm is often close to recrystallization temperature, it's not the defining criterion. Option D is a multi-level verification trap - while dynamic recovery occurs in hot working, it can also occur in some cold working scenarios.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3566, "question": "The dislocation that cannot undergo climb motion is (). \\n\\nA. Shockley partial dislocation B. Frank partial dislocation C. Edge full dislocation", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对位错类型及其运动特性的基础概念记忆，特别是Shockley部分位错、Frank部分位错和刃型全位错的基本特性区分，属于定义和分类层面的记忆性知识。 | 难度: 在选择题型中，该题目需要考生理解不同类型位错（Shockley partial dislocation, Frank partial dislocation, Edge full dislocation）的基本特性，并能够辨析它们之间的差异。虽然题目涉及的是基础概念记忆，但需要考生对位错运动机制（如climb motion）有基本的理解才能正确选择答案。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的分析或推理（等级3）。", "convertible": true, "correct_option": "A. Shockley partial dislocation", "choice_question": "The dislocation that cannot undergo climb motion is ().", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Shockley partial dislocation", "B": "Frank partial dislocation", "C": "Edge full dislocation", "D": "Screw full dislocation" }, "correct_answer": "A", "explanation": "Shockley partial dislocations cannot undergo climb motion because they are confined to glide on their slip plane due to their partial character and stacking fault. Frank partial dislocations (B) can climb as they are normal to their Burgers vector. Edge (C) and screw (D) full dislocations can both climb, with edge dislocations being particularly prone to climb due to their extra half-plane structure. The trap in B exploits the common misconception that all partial dislocations behave similarly, while D leverages the intuitive but incorrect assumption that screw dislocations cannot climb.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 897, "question": "Term explanation: Degree of supercooling", "answer": "In the phase transformation process, after cooling to a certain temperature below the phase transition point, the transformation occurs. The difference between the equilibrium phase transition temperature and this actual transformation temperature is called the degree of supercooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Degree of supercooling\"这一术语进行解释，答案提供了详细的文字说明和定义，符合简答题的特征。 | 知识层次: 题目考查对\"Degree of supercooling\"这一基本概念的定义和解释，属于基础概念的记忆和理解范畴，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求解释\"Degree of supercooling\"这一概念的定义，需要考生理解并准确描述相变过程中平衡相变温度与实际转变温度之间的差异。虽然涉及专业术语，但只需记忆和复述基本定义，不需要进行复杂的概念体系阐述或多概念比较分析。在选择题型内，这属于中等偏基础的概念性题目。", "convertible": true, "correct_option": "In the phase transformation process, after cooling to a certain temperature below the phase transition point, the transformation occurs. The difference between the equilibrium phase transition temperature and this actual transformation temperature is called the degree of supercooling.", "choice_question": "Which of the following best defines the term 'Degree of supercooling'?", "conversion_reason": "The original question is a term explanation (short answer) which can be converted into a multiple-choice question by providing the correct definition as one of the options and asking for the best definition among them.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In the phase transformation process, after cooling to a certain temperature below the phase transition point, the transformation occurs. The difference between the equilibrium phase transition temperature and this actual transformation temperature is called the degree of supercooling", "B": "The temperature difference between the melting point and the glass transition temperature in amorphous materials", "C": "The maximum temperature reduction achievable below the equilibrium freezing point before spontaneous crystallization occurs", "D": "The difference in thermal expansion coefficients between two phases during polymorphic transformations" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines degree of supercooling as the temperature difference between the equilibrium phase transition point and actual transformation temperature. Option B exploits confusion with glass transition phenomena in amorphous materials. Option C sounds plausible but incorrectly limits the concept to spontaneous crystallization. Option D strategically misdirects by using related thermodynamic terms in an incorrect context.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2047, "question": "Given that the density of fully crystalline polyethylene (PE) is 1.01 g/cm³ and that of low-density polyethylene (LDPE) is 0.92 g/cm³, calculate the size of the 'free space' in LDPE.", "answer": "The free space in LDPE is (1 cm³ / 0.92 g) - (1 cm³ / 1.01 g) = 0.097 cm³/g", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算LDPE中的'free space'），并给出了具体的密度数据和计算公式，最终需要得出一个具体的数值结果。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过已知密度值计算自由空间的大小。虽然需要理解密度的概念和自由空间的含义，但整体思维过程较为直接，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解密度的概念并应用公式进行计算，但解题步骤较为直接，仅涉及两个密度的简单比较和减法运算。不需要复杂的推理或多步骤的公式组合，因此难度等级为2。", "convertible": true, "correct_option": "0.097 cm³/g", "choice_question": "Given that the density of fully crystalline polyethylene (PE) is 1.01 g/cm³ and that of low-density polyethylene (LDPE) is 0.92 g/cm³, what is the size of the 'free space' in LDPE?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format with the correct option being the calculated value.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.097 cm³/g", "B": "0.089 cm³/g", "C": "0.105 cm³/g", "D": "0.081 cm³/g" }, "correct_answer": "A", "explanation": "The correct answer is calculated by (1/0.92 - 1/1.01) = 0.097 cm³/g, representing the specific free volume in LDPE. Option B is designed to exploit the common mistake of direct density subtraction (1.01-0.92). Option C targets those who might invert the density ratio incorrectly. Option D is a carefully constructed value close to the correct answer but based on erroneous unit conversion assumptions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 184, "question": "When using solder to join copper wires, scraping off the surface layer with a file can make the bond stronger. Please explain this phenomenon?", "answer": "When copper wires are exposed to air, their surface layer becomes covered with an adsorbed film (oxide film). When soldering copper wires, the solder only bonds the adsorbed films together, and the adhesion work between the tin and the adsorbed film is small. Using a file to remove the surface layer exposes the actual copper surface (removing the oxide film), allowing the tin to adhere firmly to the similar material of copper.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释一个现象，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释一个具体的现象，涉及铜线表面氧化膜对焊接强度的影响，需要理解氧化膜的存在及其对焊接过程的作用，并分析去除氧化膜后焊接强度提高的机理。这需要将多个概念（氧化膜、焊接、材料表面处理）关联起来进行综合分析，但不需要过于复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解铜线表面氧化膜的形成及其对焊接的影响，并能够分析去除氧化膜后焊接强度提高的原因。题目涉及中等应用层次的知识，要求考生将多个概念（氧化膜、焊接原理、材料表面处理）进行关联分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "When copper wires are exposed to air, their surface layer becomes covered with an adsorbed film (oxide film). When soldering copper wires, the solder only bonds the adsorbed films together, and the adhesion work between the tin and the adsorbed film is small. Using a file to remove the surface layer exposes the actual copper surface (removing the oxide film), allowing the tin to adhere firmly to the similar material of copper.", "choice_question": "When using solder to join copper wires, scraping off the surface layer with a file can make the bond stronger. Which of the following best explains this phenomenon?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Removing the oxide film increases the surface energy of copper, enhancing wettability by the solder", "B": "Scraping creates microstructural defects that promote interdiffusion between copper and solder", "C": "The file's abrasion generates localized heat that pre-activates the copper surface", "D": "Mechanical removal of the surface layer reduces galvanic potential differences" }, "correct_answer": "A", "explanation": "The correct answer is A because the oxide film on copper has lower surface energy than pure copper, and its removal allows better wetting by solder. Option B is a cognitive bias trap - while defects can promote diffusion, this is not the primary mechanism in soldering. Option C exploits professional intuition about thermal activation but ignores that file scraping is a room-temperature process. Option D is a multi-level verification trap, introducing an irrelevant electrochemical concept that doesn't apply to basic soldering conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1358, "question": "Analyze the essential differences in second-phase strengthening", "answer": "Second-phase strengthening: The dispersed strengthening phase particles force dislocations to cut through or bypass the strengthening phase particles, and the additional work required constitutes the dislocation mechanism of dispersed phase strengthening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析第二相强化的本质差异，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析第二相强化的本质差异，涉及位错机制的解释和强化相颗粒对位错运动的影响，需要综合运用材料科学中的位错理论和强化机制知识，进行推理分析和机理解释。 | 难度: 在选择题型内，该题目要求考生深入理解第二相强化的微观机制，包括位错切割和绕过强化相颗粒的具体过程，以及由此产生的额外功的物理意义。这需要综合运用材料科学中的位错理论和强化机制知识，进行机理层面的深度解释和复杂现象分析。因此，该题目在选择题型内属于最高难度等级。", "convertible": true, "correct_option": "Second-phase strengthening: The dispersed strengthening phase particles force dislocations to cut through or bypass the strengthening phase particles, and the additional work required constitutes the dislocation mechanism of dispersed phase strengthening.", "choice_question": "What is the essential difference in second-phase strengthening?", "conversion_reason": "The answer is a standard explanation of a concept, which can be converted into a multiple-choice question format by providing the correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The strengthening phase particles create additional stress fields that directly impede dislocation motion through long-range interactions", "B": "The dispersed strengthening phase particles force dislocations to cut through or bypass them, requiring additional work", "C": "The second phase increases the overall elastic modulus of the material, making dislocation nucleation more difficult", "D": "The phase boundaries act as perfect sinks for dislocations, eliminating strain fields in the matrix" }, "correct_answer": "B", "explanation": "The correct answer B describes the fundamental dislocation mechanism where particles either must be cut through or bypassed (Orowan mechanism). Option A incorrectly suggests long-range stress fields are primary (true for solid solution strengthening). Option C confuses second-phase strengthening with modulus effects. Option D describes an unrealistic perfect sink scenario that doesn't reflect actual dislocation-particle interactions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3061, "question": "What material is suitable for the handle of a test pen? Options: A.Polyvinyl chloride B.2Cr13 C.High-temperature ceramic D.Manganese brass", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从四个选项中选择最适合用于测试笔手柄的材料，答案形式为单一选项（A）。 | 知识层次: 题目考查对材料基本性质和适用场景的记忆和理解，属于基础概念记忆范畴。 | 难度: 该题目属于基础概念记忆类型，仅需识别和记忆常见材料的应用场景。选项A（Polyvinyl chloride）是测试笔手柄的常见材料，属于直接记忆性知识，无需复杂理解或辨析。其他选项虽然涉及不同材料，但题目要求的是基础应用场景的识别，因此难度等级为1。", "convertible": true, "correct_option": "A.Polyvinyl chloride", "choice_question": "What material is suitable for the handle of a test pen?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polyvinyl chloride", "B": "2Cr13", "C": "High-temperature ceramic", "D": "Manganese brass" }, "correct_answer": "A", "explanation": "Polyvinyl chloride (PVC) is the correct choice for test pen handles due to its excellent electrical insulation, chemical resistance, and ergonomic properties. The interference strategies are: B) 2Cr13 stainless steel seems plausible for durability but conducts electricity dangerously; C) High-temperature ceramic appears suitable for insulation but is brittle and impractical; D) Manganese brass seems mechanically robust but lacks the required electrical safety. These options exploit cognitive biases toward 'stronger' materials while overlooking the critical electrical insulation requirement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4032, "question": "A eutectoid reaction involves which of the following phases? (a) One liquid and one solid (b) One liquid and two solid (c) Two liquids and one solid (d) Three solid", "answer": "(d) Three solid", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从四个选项中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查共析反应中相的基本概念记忆，只需记住共析反应涉及三个固相即可作答，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目仅涉及对共析反应定义的基础记忆，无需复杂理解或辨析。学生只需识别共析反应涉及的相数即可直接作答，属于简单概念识别类型。", "convertible": true, "correct_option": "Three solid", "choice_question": "A eutectoid reaction involves which of the following phases?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "One liquid and one solid", "B": "One liquid and two solid", "C": "Two liquids and one solid", "D": "Three solid" }, "correct_answer": "D", "explanation": "The correct answer is D because a eutectoid reaction specifically involves the transformation of one solid phase into two new solid phases upon cooling (three solid phases total). Option A is designed to trigger confusion with eutectic reactions. Option B combines elements of both eutectic and eutectoid reactions. Option C is a complete fabrication but uses plausible-sounding phase combinations. These distractors exploit the tendency of AI systems to conflate similar-sounding material science concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3257, "question": "After high-temperature recovery, several edge dislocations form a subgrain boundary with a misorientation of $0.057^{\\\\circ}$. Assuming there is no interaction between these dislocations, what is the ratio of the distortion energy after forming the subgrain to the original energy? (Given the core radius of the dislocation $r_{0}\\\\approx$ $b\\\\approx10^{-8}\\\\mathrm{cm}$, and the effective radius of the dislocation stress field before forming the subgrain $R=10^{-4}\\\\mathrm{cm}$.)", "answer": "Given the core radius of the dislocation $r_{0}=b\\\\approx10^{-8}~\\\\mathrm{cm}$ and the effective radius of the dislocation stress field $R=10^{-4}$ $\\\\mathrm{{cm}}$, since the total length of dislocations remains unchanged before and after forming the subgrain, the ratio of the energy per unit dislocation line before and after forming the subgrain is equal to the ratio of the energy before and after polygonization. The energy per unit dislocation line is $$ W_{E}=\\\\frac{G b^{2}}{4\\\\pi(1-\\\\nu)}\\\\ln\\\\frac{R}{r_{0}}=\\\\frac{G b^{2}}{4\\\\pi(1-\\\\nu)}\\\\ln10^{4} $$ After polygonization, the edge dislocations are arranged perpendicular to the slip plane with a spacing of $D$, so the effective radius of the dislocation $R$ becomes $D$. From the formula $R=D=\\\\frac{b}{\\\\theta}=\\\\frac{10^{-8}}{10^{-3}}=10^{-5}$, the energy per unit dislocation line after polygonization is $$ W_{E}^{\\\\prime}={\\\\frac{G b^{2}}{4\\\\pi(1-\\\\nu)}}\\\\cdot\\\\ln{\\\\frac{10^{-5}}{10^{-8}}}={\\\\frac{G b^{2}}{4\\\\pi(1-\\\\nu)}}\\\\cdot\\\\ln10^{3} $$ $$ \\\\frac{W_{E}^{\\\\prime}}{W_{E}}=\\\\frac{\\\\ln{10^{3}}}{\\\\ln{10^{4}}}=\\\\frac{3}{4} $$ This shows that after polygonization, the dislocation energy decreases, reducing the stored energy and also the driving force for recrystallization.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解变形能量比，解答过程中涉及到了具体的数学运算和公式推导，最终得出一个具体的数值结果。 | 知识层次: 题目涉及多步计算和概念关联，需要理解位错能量公式的应用，并综合运用位错间距与取向差的关系进行计算。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力来推导能量比。 | 难度: 在选择题中属于中等偏上难度，需要理解位错能量计算、多边形化过程以及能量比值的推导。题目涉及多步骤计算（包括对数运算和单位转换）和多个材料科学概念的关联（位错应力场、多边形化、存储能量变化）。虽然提供了关键公式和参数，但需要考生综合运用这些信息进行推导，属于典型的综合性计算问题。", "convertible": true, "correct_option": "\\frac{3}{4}", "choice_question": "After high-temperature recovery, several edge dislocations form a subgrain boundary with a misorientation of $0.057^{\\circ}$. Assuming there is no interaction between these dislocations, what is the ratio of the distortion energy after forming the subgrain to the original energy? (Given the core radius of the dislocation $r_{0}\\approx$ $b\\approx10^{-8}\\mathrm{cm}$, and the effective radius of the dislocation stress field before forming the subgrain $R=10^{-4}\\mathrm{cm}$.)", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, which can be converted into a multiple-choice question format. The correct answer is derived from the given solution.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3/4", "B": "1/2", "C": "ln(R/r0)/[2ln(R/2r0)]", "D": "θ/2π" }, "correct_answer": "A", "explanation": "The correct answer is A (3/4) because the distortion energy of dislocations in a subgrain boundary is reduced due to mutual cancellation of stress fields. The energy ratio can be derived from the logarithmic terms in dislocation energy calculations. Option B (1/2) is a common intuitive but incorrect guess for energy reduction. Option C (ln(R/r0)/[2ln(R/2r0)]) appears mathematically sophisticated but misapplies the logarithmic terms. Option D (θ/2π) incorrectly relates the misorientation angle directly to energy reduction, exploiting the angle's prominence in the problem statement.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3467, "question": "Why does alloy steel have less heat treatment deformation than carbon steel?", "answer": "The addition of alloying elements (except C) increases the hardenability of the steel, so when obtaining the same structure, alloy steel can choose a slower cooling medium, resulting in less heat treatment deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释合金钢比碳钢热处理变形小的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释合金钢与碳钢在热处理变形方面的差异，涉及合金元素对淬透性的影响、冷却介质选择与组织转变的关系等复杂机理分析，需要综合运用材料科学原理进行推理和解释。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅理解合金钢和碳钢的基本区别，还需要掌握合金元素对钢的淬透性影响这一较深层次的机理知识。正确选项涉及多个关键概念的综合运用（合金元素、淬透性、冷却介质选择、热处理变形关系），需要考生进行机理层面的推理分析才能准确作答。这种需要将多个专业知识模块串联起来解释复杂现象的题目，在选择题中属于难度较高的类型。", "convertible": true, "correct_option": "The addition of alloying elements (except C) increases the hardenability of the steel, so when obtaining the same structure, alloy steel can choose a slower cooling medium, resulting in less heat treatment deformation.", "choice_question": "Why does alloy steel have less heat treatment deformation than carbon steel?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Alloying elements increase hardenability, allowing slower cooling rates that reduce thermal stresses", "B": "Alloy steels have higher thermal conductivity which homogenizes temperature gradients during quenching", "C": "The presence of alloy carbides creates a rigid lattice structure resistant to distortion", "D": "Alloying elements lower the martensite start temperature, reducing phase transformation stresses" }, "correct_answer": "A", "explanation": "Correct answer A is right because alloying elements (except C) increase hardenability, enabling slower cooling rates that minimize thermal stresses and distortion. Option B is wrong because alloy steels typically have lower thermal conductivity. Option C is misleading as alloy carbides don't directly prevent distortion. Option D is incorrect because while Ms temperature is affected, the primary mechanism is the hardenability effect on cooling rates.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4523, "question": "Estimate the minimum thermal conductivity value for a cermet that contains 85 vol % titanium carbide (TiC) particles in a cobalt matrix. Assume thermal conductivities of 27 and 69 W/m-K for TiC and Co, respectively.", "answer": "the minimum thermal conductivity k_min is 29.7 W/m-K.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计cermet的最小热导率值，答案是一个具体的数值结果（29.7 W/m-K），这符合计算题的特征。 | 知识层次: 题目需要应用复合材料热导率的最小值计算公式，涉及多步计算和不同材料热导率的综合考量，但不需要复杂的推理分析或创新设计。 | 难度: 在选择题中属于中等难度，需要理解复合材料热导率的最小值计算原理，并正确应用串联模型公式进行多步计算。题目涉及两个材料的热导率数据整合和体积分数换算，属于综合性计算问题，但选项已给出正确答案降低了部分难度。", "convertible": true, "correct_option": "29.7 W/m-K", "choice_question": "Estimate the minimum thermal conductivity value for a cermet that contains 85 vol % titanium carbide (TiC) particles in a cobalt matrix. Assume thermal conductivities of 27 and 69 W/m-K for TiC and Co, respectively.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "29.7 W/m-K", "B": "32.4 W/m-K", "C": "24.1 W/m-K", "D": "69.0 W/m-K" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the inverse rule of mixtures for thermal conductivity in particulate composites: 1/k_min = Vf/kf + Vm/km, where Vf=0.85, kf=27 W/m-K, Vm=0.15, km=69 W/m-K. Option B is a common error from using arithmetic mean instead of harmonic mean. Option C results from incorrectly reversing the volume fractions. Option D is the pure cobalt conductivity, a trap for those who ignore the composite nature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 348, "question": "(Taking the face-centered cubic unit cell as an example) What are the common parameters used to describe the characteristics of a crystal structure (unit cell)? What is the coordination number of an FCC unit cell?", "answer": "Coordination number 12.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求描述晶体结构的常见参数，并给出FCC晶胞的配位数，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查晶体结构的基本参数和面心立方晶胞的配位数，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目仅要求记忆并识别面心立方晶胞的配位数这一基础定义，无需解释或分析多个概念。正确选项直接给出了答案，解题步骤简单，属于最基础的概念记忆题。", "convertible": true, "correct_option": "Coordination number 12", "choice_question": "What is the coordination number of an FCC unit cell?", "conversion_reason": "The answer is a standard term (coordination number 12) which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项D", "B": "选项B", "C": "选项C", "D": "Coordination number 12" }, "correct_answer": "D", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1771, "question": "11．The crystallographic characteristics of martensitic transformation are manifested as: _（26）_, etc.", "answer": "（26）the presence of habit plane", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（habit plane）来描述马氏体转变的晶体学特征，这属于需要文字解释和论述的简答题类型。答案不是从多个选项中选择，也不是判断对错或进行数值计算。 | 知识层次: 题目考查马氏体相变的基本晶体学特征，属于基础概念的记忆和理解范畴，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对马氏体相变基本特征的记忆，属于基础概念的直接回忆。题目仅要求识别\"habit plane\"这一特定术语，无需解释或分析，符合等级1的基本定义简答要求。", "convertible": true, "correct_option": "the presence of habit plane", "choice_question": "The crystallographic characteristics of martensitic transformation are manifested as:", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by providing the correct option and distractor options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "the presence of habit plane", "B": "a diffusion-controlled phase transition", "C": "continuous change in lattice parameters", "D": "formation of equiaxed grains" }, "correct_answer": "A", "explanation": "The correct answer is A because martensitic transformation is characterized by a specific habit plane between parent and product phases. B is incorrect as martensitic transformation is diffusionless, not diffusion-controlled. C is a trap as it describes continuous transformations, while martensitic is displacive. D exploits the common misconception that all phase transformations result in equiaxed microstructures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4368, "question": "What is one important difference between continuous cooling transformation diagrams for plain carbon and alloy steels regarding the presence of a bainite nose?", "answer": "For an alloy steel, a bainite nose will be present, which nose will be absent for plain carbon alloys.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释连续冷却转变图中普通碳钢和合金钢在贝氏体鼻部存在方面的重要差异，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求比较两种钢的连续冷却转变图特征，涉及对合金元素影响的理解和概念关联，需要中等程度的分析和应用能力。 | 难度: 在选择题中属于中等难度，需要理解连续冷却转变图的基本概念，并能区分普通碳钢和合金钢在贝氏体鼻部存在与否的关键差异。虽然题目涉及的知识点较为专业，但在选择题型中通过正确选项可以直接对比分析，无需进行多步计算或深度关联性分析。", "convertible": true, "correct_option": "For an alloy steel, a bainite nose will be present, which nose will be absent for plain carbon alloys.", "choice_question": "What is one important difference between continuous cooling transformation diagrams for plain carbon and alloy steels regarding the presence of a bainite nose?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Alloy steels exhibit a bainite nose due to their slower diffusion rates, while plain carbon steels lack this feature", "B": "Plain carbon steels show a bainite nose at higher cooling rates, whereas alloy steels never form bainite", "C": "The bainite nose appears at identical positions for both steel types but requires different alloying elements to activate", "D": "Both steel types display bainite noses, but alloy steels require isothermal holding to reveal it" }, "correct_answer": "A", "explanation": "Correct answer A highlights the key metallurgical difference: alloying elements retard diffusion, creating the bainite nose phenomenon absent in plain carbon steels. Option B reverses the truth about bainite formation. Option C falsely suggests identical nose positions. Option D incorrectly states both steels show bainite noses and introduces an irrelevant isothermal condition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1173, "question": "What type of solid solution can be formed when the atomic radius of the solute is similar to that of the solvent?", "answer": "Substitutional", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述来回答问题，答案是一个具体的术语而非选择或判断 | 知识层次: 题目考查的是对固溶体类型的基础概念记忆和理解，特别是当溶质和溶剂原子半径相似时形成的置换型固溶体。这属于材料科学中的基本分类知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即对固溶体类型的定义和分类的记忆。题目直接询问当溶质和溶剂的原子半径相似时形成的固溶体类型，正确答案\"Substitutional\"是基础定义的一部分，无需复杂推理或概念间的比较分析。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "Substitutional", "choice_question": "What type of solid solution can be formed when the atomic radius of the solute is similar to that of the solvent?", "conversion_reason": "The answer is a standard term (Substitutional), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Substitutional", "B": "Interstitial", "C": "Intermetallic", "D": "Amorphous" }, "correct_answer": "A", "explanation": "The correct answer is A (Substitutional) because when the atomic radii of solute and solvent are similar, solute atoms can directly substitute for solvent atoms in the crystal lattice. B (Interstitial) is incorrect as it requires much smaller solute atoms. C (Intermetallic) is a trap for those confusing solid solutions with compounds. D (Amorphous) exploits the common misconception that similar-sized atoms may disrupt crystalline structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1521, "question": "After cold plastic deformation, the strength and hardness of metal (23)—", "answer": "(23) increase", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个单词\"increase\"作为答案，属于简短的文字回答形式，不需要选择或判断，也不需要计算 | 知识层次: 题目考查冷塑性变形后金属强度和硬度变化的基本概念记忆，属于基础概念记忆性知识 | 难度: 在选择题型中属于基础难度，仅需记忆金属冷塑性变形后强度和硬度增加的基本原理，无需复杂分析或概念比较。", "convertible": true, "correct_option": "increase", "choice_question": "After cold plastic deformation, the strength and hardness of metal (23)—", "conversion_reason": "简答题的答案是标准术语，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "increase due to dislocation entanglement and grain refinement", "B": "decrease as atomic bonds weaken under strain", "C": "remain unchanged as it's an intrinsic property", "D": "first increase then decrease due to strain hardening saturation" }, "correct_answer": "A", "explanation": "The correct answer is A because cold working introduces dislocations that become entangled, increasing strength via strain hardening, while grain boundaries act as barriers to dislocation motion. Option B exploits the misconception that plastic deformation breaks atomic bonds rather than just displacing atoms. Option C targets confusion between intrinsic properties (like elastic modulus) and structure-sensitive properties. Option D mimics a real phenomenon (dynamic recovery) but applies it to the wrong deformation regime.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1585, "question": "In fluorite, what type of voids are entirely occupied by F- ions?", "answer": "Tetrahedral", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用简短的文字回答特定类型的问题，答案是一个专业术语而非选择或判断 | 知识层次: 题目考查对氟化钙晶体结构中空隙类型的基础概念记忆，仅需识别F-离子占据的空隙类型，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即氟化钙（萤石）结构中F-离子占据的空隙类型。题目直接给出正确选项\"Tetrahedral\"，无需任何解释或推理过程，属于最简单的定义性知识考查。", "convertible": true, "correct_option": "Tetrahedral", "choice_question": "In fluorite, what type of voids are entirely occupied by F- ions?", "conversion_reason": "The answer is a standard term (Tetrahedral), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Tetrahedral", "B": "Octahedral", "C": "Cubic", "D": "Trigonal bipyramidal" }, "correct_answer": "A", "explanation": "In fluorite (CaF2) structure, the F- ions occupy all the tetrahedral voids in the face-centered cubic (FCC) arrangement of Ca2+ ions. The key distraction here is option B (Octahedral), which exploits the common confusion between fluorite and rock salt structures where anions occupy octahedral voids. Option C (Cubic) is a geometric trap based on the cubic symmetry of the unit cell, while option D (Trigonal bipyramidal) targets those who might overcomplicate the coordination geometry analysis.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1151, "question": "What effect does constitutional supercooling have on crystal growth morphology?", "answer": "During the crystallization of solid solutions, constitutional supercooling significantly influences the morphology of crystal growth, leading to the formation of cellular structures or even dendritic crystals even under a positive temperature gradient. Specifically, without constitutional supercooling, the interface advances in a planar manner; with slight constitutional supercooling, the interface becomes cellular; and with substantial constitutional supercooling, the interface turns dendritic.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释 constitutional supercooling 对晶体生长形态的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及对constitutional supercooling对晶体生长形态影响的深入分析和解释，需要综合运用相关概念和机理，理解不同条件下的界面形态变化，并进行推理分析。 | 难度: 在选择题型中，该题目属于最高难度等级。题目涉及复杂的材料科学机理（成分过冷对晶体生长形貌的影响），要求考生不仅理解成分过冷的概念，还需要掌握其对晶体生长界面形貌（平面状→胞状→枝晶状）的渐进影响机制。正确选项包含三个层次的分析（无成分过冷、轻微成分过冷、显著成分过冷），需要综合运用相变动力学和扩散理论进行推理判断，完全符合\"复杂现象全面分析\"的知识层次要求。在选择题型中，这种需要多维度机理解释和现象分析的题目属于最难的类别。", "convertible": true, "correct_option": "During the crystallization of solid solutions, constitutional supercooling significantly influences the morphology of crystal growth, leading to the formation of cellular structures or even dendritic crystals even under a positive temperature gradient. Specifically, without constitutional supercooling, the interface advances in a planar manner; with slight constitutional supercooling, the interface becomes cellular; and with substantial constitutional supercooling, the interface turns dendritic.", "choice_question": "What effect does constitutional supercooling have on crystal growth morphology?", "conversion_reason": "The answer is a standard explanation of the effect of constitutional supercooling on crystal growth morphology, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Constitutional supercooling promotes planar growth by stabilizing the solid-liquid interface", "B": "It causes solute segregation but has negligible effect on growth morphology", "C": "It leads to cellular or dendritic growth by creating localized undercooled regions ahead of the interface", "D": "Constitutional supercooling only affects growth rate, not morphology" }, "correct_answer": "C", "explanation": "Correct answer C describes the actual effect where localized undercooling destabilizes the planar interface, leading to cellular/dendritic structures. Option A is a reversal trap - constitutional supercooling destabilizes planar growth. Option B exploits the common misconception that segregation and morphology effects can be decoupled. Option D targets the AI's potential failure to distinguish between growth rate and morphology effects, which are fundamentally coupled in this phenomenon.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2635, "question": "Explain the characteristics of thermoplastic polymer materials from the perspective of polymer chain structure", "answer": "Thermoplastic polymers have linear and branched polymer chain structures, which soften upon heating and can be repeatedly processed and reshaped", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释热塑性聚合物材料的特性，需要从聚合物链结构的角度进行文字解释和论述，答案也提供了详细的文字说明，符合简答题的特征。 | 知识层次: 题目考查对热塑性聚合物链结构特征的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生从聚合物链结构的角度解释热塑性聚合物材料的特性，正确选项提供了线性与支化链结构、加热软化以及可重复加工等关键特征。虽然需要一定的记忆和理解，但不需要复杂的分析或比较多个概念，属于中等偏下的难度水平。", "convertible": true, "correct_option": "Thermoplastic polymers have linear and branched polymer chain structures, which soften upon heating and can be repeatedly processed and reshaped", "choice_question": "Which of the following describes the characteristics of thermoplastic polymer materials from the perspective of polymer chain structure?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question. The original question can be rephrased to fit a multiple-choice format by asking for the correct description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermoplastic polymers have linear and branched polymer chain structures, which soften upon heating and can be repeatedly processed and reshaped", "B": "Thermoplastic polymers exhibit crosslinked network structures that prevent chain slippage, resulting in permanent shape retention upon cooling", "C": "Thermoplastic polymers contain ionic bonds between chains that break at elevated temperatures, allowing for reversible processing", "D": "Thermoplastic polymers possess crystalline domains connected by covalent bonds that melt completely at processing temperatures" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental characteristic of thermoplastics having linear/branched chains that allow reversible softening. Option B incorrectly describes thermoset characteristics. Option C falsely introduces ionic bonding which is irrelevant. Option D incorrectly suggests covalent bonding between crystalline domains, confusing processing behavior with molecular structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 33, "question": "In MgO, the unit cell parameter a=0.420 nm, and the anions and cations are in contact with each other. Calculate the radius of Mg2+. The radius of O2- is known to be 0.097 nm.", "answer": "In MgO, a=0.420 nm, and the anions and cations are in contact with each other. a=2(r+ + r-), therefore rMg2+=(0.420 nm / 2) - 0.097 nm = 0.113 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解Mg2+的半径，答案给出了具体的计算过程和结果。 | 知识层次: 题目涉及基本的公式应用和简单计算，只需要直接套用已知的半径关系和单位晶胞参数进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（a=2(r+ + r-)）进行计算，解题步骤简单明了，无需复杂的推理或多步骤操作。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "0.113 nm", "choice_question": "In MgO, the unit cell parameter a=0.420 nm, and the anions and cations are in contact with each other. The radius of O2- is known to be 0.097 nm. Calculate the radius of Mg2+.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.113 nm", "B": "0.097 nm", "C": "0.210 nm", "D": "0.084 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.113 nm) because in the rock salt structure of MgO, the unit cell parameter a is related to the ionic radii by a = 2(r_Mg2+ + r_O2-). Given a=0.420 nm and r_O2-=0.097 nm, solving for r_Mg2+ gives 0.113 nm. Option B (0.097 nm) exploits the cognitive bias of assuming cation and anion radii are equal. Option C (0.210 nm) is a/2, tempting those who forget to subtract the oxygen radius. Option D (0.084 nm) is designed to catch those who incorrectly subtract the oxygen radius from a/2.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 239, "question": "Concentration gradient causes diffusion, does diffusion always proceed from high concentration to low concentration? Why?", "answer": "Diffusion is caused by gradient differences, and concentration gradient is only one type of gradient difference. When another gradient difference, such as stress gradient, has a greater influence than the concentration gradient, diffusion can proceed from low concentration to high concentration.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释扩散是否总是从高浓度向低浓度进行，并需要提供原因。答案通过文字解释和论述来回答，没有涉及选择、判断或计算。 | 知识层次: 题目不仅考查扩散的基本概念（浓度梯度），还需要理解其他梯度（如应力梯度）对扩散方向的影响，涉及多因素的综合分析和机理解释，思维深度较高。 | 难度: 在选择题型中，该题目属于最高难度等级。题目不仅要求理解扩散的基本概念（浓度梯度驱动），还需要考生综合运用其他梯度差异（如应力梯度）的知识，进行复杂现象的全面分析。正确选项涉及机理深度解释和多个概念的比较推理，远超单一知识点的简单记忆或理解，符合选择题型内对复杂现象全面分析的最高要求。", "convertible": true, "correct_option": "Diffusion is caused by gradient differences, and concentration gradient is only one type of gradient difference. When another gradient difference, such as stress gradient, has a greater influence than the concentration gradient, diffusion can proceed from low concentration to high concentration.", "choice_question": "Does diffusion always proceed from high concentration to low concentration? Why?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct explanation as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because Fick's first law explicitly states diffusion flux is proportional to the negative concentration gradient", "B": "No, because in spinodal decomposition diffusion occurs against the concentration gradient due to chemical potential gradients", "C": "Only in isotropic materials, as anisotropic materials exhibit direction-dependent diffusion behavior", "D": "Yes, but only when temperature gradients are absent from the system" }, "correct_answer": "B", "explanation": "The correct answer is B because spinodal decomposition is a classic example where diffusion occurs from low to high concentration regions due to the dominance of chemical potential gradients over concentration gradients. Option A is a cognitive bias trap that appeals to oversimplified interpretation of Fick's law. Option C exploits intuition about material anisotropy but is irrelevant to the fundamental thermodynamic driving force. Option D creates a false constraint by introducing temperature gradients which aren't necessary for reverse diffusion phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1217, "question": "Why does metal slip occur on the closest-packed planes and directions?", "answer": "The slip in metal crystals occurs on the closest-packed planes and directions under external force because the atomic spacing is the smallest and the bonding force is the strongest on these planes, while the distance between two adjacent closest-packed planes is the largest and the bonding force is the weakest. It can be inferred that the resistance to slip is the smallest between the closest-packed atomic planes, requiring the least external force. Therefore, the closest-packed atomic planes and directions become the slip planes and slip directions for crystal slip.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释金属滑移发生在最密排面和方向的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释金属滑移发生在最密排面和方向的原因，涉及原子间距、键合力以及滑移阻力的综合分析。这需要深入理解晶体结构和滑移机制，并进行推理分析，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求深入理解金属晶体滑移的微观机制，包括原子间距、键合力与滑移阻力之间的关系，并能综合运用这些知识进行推理分析。正确选项不仅需要识别最密排面和方向的特征，还要解释为什么这些特定平面和方向成为滑移的首选路径，涉及复杂现象的全面分析。这种题目超越了简单记忆或单一概念应用，要求考生具备机理深度解释和综合推理能力。", "convertible": true, "correct_option": "The slip in metal crystals occurs on the closest-packed planes and directions under external force because the atomic spacing is the smallest and the bonding force is the strongest on these planes, while the distance between two adjacent closest-packed planes is the largest and the bonding force is the weakest. It can be inferred that the resistance to slip is the smallest between the closest-packed atomic planes, requiring the least external force. Therefore, the closest-packed atomic planes and directions become the slip planes and slip directions for crystal slip.", "choice_question": "Why does metal slip occur on the closest-packed planes and directions?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The highest atomic density planes require the least energy for dislocation nucleation", "B": "The electrostatic repulsion between slip planes is minimized in close-packed directions", "C": "The Burgers vector length is shortest in close-packed directions, reducing strain energy", "D": "The Peierls-Nabarro stress reaches its minimum value on close-packed planes" }, "correct_answer": "C", "explanation": "Correct answer (C) combines two key facts: 1) Burgers vector magnitude is minimized in close-packed directions, and 2) shorter Burgers vectors require less strain energy for dislocation motion. Option A is tempting because it mentions dislocation nucleation (a higher-order concept) but incorrectly focuses on nucleation rather than motion. Option B exploits electrostatic intuition but misapplies it to metallic bonding. Option D uses the Peierls-Nabarro concept correctly but falsely assigns it as the primary reason rather than a secondary effect. Advanced AI might select D due to its technical sophistication, while human experts would recognize C as the fundamental explanation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3020, "question": "If crystalline regions exist in polymer materials, then their melting point is (1). A. Fixed B. A temperature softening range C. Above the glass transition temperature D. Above the flow temperature", "answer": "(1)C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项A、B、C、D中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查聚合物材料中结晶区域熔点与玻璃化转变温度之间关系的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题中属于中等偏下难度，需要理解聚合物材料中结晶区的熔点特性，并知道其与玻璃化转变温度的关系。虽然涉及基础概念记忆，但需要一定的概念理解和简单辨析能力，而非纯粹的直接记忆。", "convertible": true, "correct_option": "C. Above the glass transition temperature", "choice_question": "If crystalline regions exist in polymer materials, then their melting point is:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Directly proportional to the degree of crystallinity", "B": "Independent of molecular weight distribution", "C": "Determined solely by the strongest covalent bonds in the polymer", "D": "Inversely related to the lamellar thickness of crystallites" }, "correct_answer": "D", "explanation": "The correct answer is D because the melting point of crystalline regions in polymers is directly proportional to lamellar thickness (Thomson-Gibbs equation). Option A exploits the common misconception that melting point increases linearly with crystallinity degree, while in reality it's more complex. Option B targets the AI's potential oversight of how molecular weight distribution affects crystal perfection. Option C is a deep trap using the intuitive but incorrect assumption about covalent bond strength dominating thermal properties in polymers.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 714, "question": "There are countless translational axes in the crystal structure", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查晶体结构中平移轴的基本概念记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念正误判断，仅需记忆晶体结构中存在无数平移轴这一基本原理即可做出正确选择，无需复杂理解或分析步骤。", "convertible": true, "correct_option": "√", "choice_question": "There are countless translational axes in the crystal structure", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials exhibit short-range order but completely lack any long-range order.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While amorphous materials do exhibit short-range order, some may display medium-range order (2-5nm scale) which is not strictly long-range but goes beyond pure short-range. The absolute statement 'completely lack any long-range order' is too strong, as certain amorphous materials may show very limited structural correlations over longer distances.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3093, "question": "What types can composites be classified into based on the types of reinforcing materials?", "answer": "Fiber-reinforced composites, particle-reinforced composites, and laminated composites.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释复合材料基于增强材料类型的分类，答案以文字形式给出具体分类，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查复合材料按增强材料类型分类的基本概念记忆和理解 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即复合材料根据增强材料类型的分类。正确选项直接给出了三种明确的分类（纤维增强、颗粒增强和层压复合材料），无需复杂推理或概念间的比较分析。属于最基本的选择题难度，只需识别和回忆定义性知识即可作答。", "convertible": true, "correct_option": "Fiber-reinforced composites, particle-reinforced composites, and laminated composites", "choice_question": "Based on the types of reinforcing materials, composites can be classified into which of the following?", "conversion_reason": "The answer is a standard list of terms, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fiber-reinforced, particle-reinforced, and structural composites", "B": "Continuous fiber, discontinuous fiber, and nano-reinforced composites", "C": "Fiber-reinforced, particle-reinforced, and laminated composites", "D": "Metal matrix, ceramic matrix, and polymer matrix composites" }, "correct_answer": "C", "explanation": "The correct classification is based on the geometry/orientation of reinforcing materials (fiber, particle, laminate). Option A incorrectly includes 'structural composites' which is a functional classification. Option B focuses on fiber sub-types rather than the fundamental classification. Option D describes matrix material types, not reinforcement types. Advanced AIs might confuse matrix-based classification (D) with reinforcement-based classification due to common dataset biases in materials science literature.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2518, "question": "Explain the term: sublattice", "answer": "The respective Bravais lattices occupied by the constituent atoms in an ordered solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释术语\"sublattice\"，需要文字解释和论述，答案也是以文字形式给出的定义说明 | 知识层次: 题目考查对\"sublattice\"这一基本概念的定义和记忆，属于材料科学中晶体结构的基础知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生对\"sublattice\"这一术语进行概念解释和描述，属于基础概念记忆层次。虽然需要理解并准确描述该术语的定义，但并不涉及复杂的概念体系阐述或多概念比较分析，因此在选择题型内属于中等难度（等级2）。", "convertible": true, "correct_option": "The respective Bravais lattices occupied by the constituent atoms in an ordered solid solution.", "choice_question": "Which of the following best defines the term 'sublattice'?", "conversion_reason": "The answer is a standard definition of a term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The respective Bravais lattices occupied by the constituent atoms in an ordered solid solution", "B": "A secondary lattice structure formed by defects in a crystalline material", "C": "The reciprocal lattice representation of a crystal's diffraction pattern", "D": "A partial lattice formed during intermediate stages of crystallization" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines sublattices as the distinct Bravais lattices formed by different atomic species in ordered solid solutions. Option B exploits the cognitive bias of associating 'sub-' with defects rather than ordered structures. Option C leverages the professional intuition trap by confusing real-space lattices with reciprocal space representations. Option D creates a multi-level verification trap by introducing a plausible but incorrect temporal dimension to lattice formation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2308, "question": "Parameters of short fiber composite: $\\\\varphi_{\\\\mathrm{f}}=0.4$, $d_{\\\\mathrm{t}}=25\\\\mu\\\\mathrm{m}$, $\\\\sigma_{\\\\mathrm{{\\\\scriptscriptstyle M}}}=2500\\\\mathrm{MPa}$, $\\\\sigma_{\\\\mathfrak{m u}}=275~\\\\mathrm{MPa}$, and the interfacial shear strength between fiber and matrix is $200\\\\mathrm{MPa}$. Assuming the fiber stress varies linearly at both ends of the fiber, approximately estimate the strength of the randomly oriented short fiber composite when the fiber length is $1~\\\\mathrm{mm}$.", "answer": "Since the fiber fracture strain and the stress-strain curve of the matrix are not given, it is difficult to determine $\\\\sigma_{\\\\mathrm{m}}^{*}$. Thus, $\\\\sigma_{\\\\mathrm{mu}}$ is used to approximate $\\\\sigma_{\\\\mathrm{m}}^{*}$, and $200\\\\mathrm{MPa}$ is used to approximate $\\\\tau_{y}$. First, calculate $L_{\\\\mathrm{c}}$: $$ $$ $\\\\sigma_{\\\\mathrm{cu}}=\\\\Big(1-\\\\frac{L_{\\\\mathrm{c}}}{2L}\\\\Big)\\\\sigma_{\\\\mathrm{fu}}\\\\varphi_{\\\\mathrm{f}}+\\\\sigma_{\\\\mathrm{m}}^{*}(1-\\\\varphi_{\\\\mathrm{f}})=$ $$ $\\\\left(1-\\\\frac{156.25\\\\times10^{-6}\\\\mathrm{m}}{2\\\\times1.0\\\\times10^{-3}\\\\mathrm{m}}\\\\right)\\\\times2~500~\\\\mathrm{MPa}\\\\times0.4+275~\\\\mathrm{MPa}\\\\times0.6=1~087~\\\\mathrm{MPa}$ The strength of the randomly oriented short fiber composite is approximately $\\\\mathrm{~1~}087\\\\mathrm{~MPa}$. $L_{\\\\mathrm{{c}}}={\\\\frac{d_{\\\\mathrm{{t}}}\\\\sigma_{\\\\mathrm{{fu}}}}{2\\\\tau_{\\\\mathrm{{y}}}}}\\\\approx{\\\\frac{25\\\\times10^{-6}~{\\\\mathrm{m}}\\\\times2~500~{\\\\mathrm{MPa}}}{2\\\\times200~{\\\\mathrm{MPa}}}}=156.25\\\\times10^{-6}~{\\\\mathrm{m}}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过数值计算和公式应用来估算随机取向短纤维复合材料的强度，答案中包含了具体的计算步骤和公式应用，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要计算临界纤维长度（Lc）并应用复合材料的强度公式，同时需要理解纤维和基体的应力分布以及界面剪切强度的作用。虽然不涉及复杂的机理分析或创新设计，但需要综合应用多个概念和公式进行中等难度的计算。 | 难度: 在选择题中属于高难度，题目涉及多步复杂计算和多个材料参数的关联分析。需要计算临界纤维长度（Lc），并应用复合材料的强度公式进行综合计算。此外，题目还要求对未给定的参数进行合理近似（如用σmu近似σm*），这增加了题目的复杂性和对概念理解的深度要求。在选择题型中，这种需要多变量处理和综合判断的题目属于较高难度等级。", "convertible": true, "correct_option": "1 087 MPa", "choice_question": "Parameters of short fiber composite: $\\varphi_{\\mathrm{f}}=0.4$, $d_{\\mathrm{t}}=25\\mu\\mathrm{m}$, $\\sigma_{\\mathrm{{\\scriptscriptstyle M}}}=2500\\mathrm{MPa}$, $\\sigma_{\\mathfrak{m u}}=275~\\mathrm{MPa}$, and the interfacial shear strength between fiber and matrix is $200\\mathrm{MPa}$. Assuming the fiber stress varies linearly at both ends of the fiber, approximately estimate the strength of the randomly oriented short fiber composite when the fiber length is $1~\\mathrm{mm}$.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1087 MPa", "B": "825 MPa", "C": "1560 MPa", "D": "475 MPa" }, "correct_answer": "A", "explanation": "正确答案A基于正确的复合材料强度计算模型，考虑了纤维取向随机分布因子0.375和临界长度计算。干扰项B错误地直接取用了基体强度275MPa与纤维强度2500MPa的线性组合。干扰项C是典型的单位混淆错误，错误地将微米级直径换算为毫米级进行计算。干扰项D则错误地使用了弹性模量比值而非强度比值进行计算。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1721, "question": "What effect does constitutional supercooling have on the solidification structure of alloys?", "answer": "The occurrence of constitutional supercooling phenomenon will cause multicomponent alloys to develop cellular or dendritic structures even under a positive temperature gradient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释constitutional supercooling对合金凝固结构的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及合金凝固过程中成分过冷现象对凝固组织的影响，需要理解成分过冷的形成机制及其与凝固组织形貌的关系，属于对材料科学中凝固理论的深入分析和机理解释。 | 难度: 在选择题型中，该题目属于最高难度等级。题目涉及复杂的合金凝固现象，要求考生不仅理解\"成分过冷\"的概念，还需要掌握其对凝固组织的影响机制。正确选项需要综合温度梯度、多组分合金特性以及凝固组织形态学等多方面知识进行推理分析。这种题目在选择题中属于对机理深度解释和复杂现象全面分析要求最高的类型，需要考生具备扎实的理论基础和综合分析能力。", "convertible": true, "correct_option": "The occurrence of constitutional supercooling phenomenon will cause multicomponent alloys to develop cellular or dendritic structures even under a positive temperature gradient.", "choice_question": "What effect does constitutional supercooling have on the solidification structure of alloys?", "conversion_reason": "The answer is a standard and specific description of the effect, which can be used as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Causes cellular/dendritic growth by creating local solute-rich zones ahead of the interface", "B": "Promotes planar front solidification by enhancing thermal gradient stability", "C": "Induces equiaxed grain formation through homogeneous nucleation", "D": "Reduces microsegregation by accelerating diffusion at the solid-liquid interface" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual mechanism where solute rejection creates compositionally supercooled zones that destabilize the planar interface. Option B reverses the effect by suggesting stabilization. Option C confuses constitutional supercooling with bulk undercooling effects. Option D incorrectly associates the phenomenon with reduced segregation when it actually exacerbates it.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3311, "question": "What is the microstructure transformation of quenched steel during tempering at 100-250°C?", "answer": "Decomposition of martensite", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释淬火钢在100-250°C回火时的微观结构转变，答案需要文字描述（马氏体分解），属于简答题类型。 | 知识层次: 题目考查对淬火钢在回火过程中微观结构转变的理解，需要将马氏体分解的概念与特定温度范围（100-250°C）联系起来，属于中等应用层次。虽然不涉及复杂计算，但需要综合理解和应用相关知识。 | 难度: 在选择题中属于中等难度，需要理解马氏体分解的概念，并能够将其与回火温度范围（100-250°C）联系起来。这涉及对钢的热处理过程中微观结构变化的综合分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Decomposition of martensite", "choice_question": "What is the microstructure transformation of quenched steel during tempering at 100-250°C?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Formation of lower bainite", "B": "Decomposition of martensite", "C": "Precipitation of epsilon-carbides", "D": "Recrystallization of ferrite" }, "correct_answer": "B", "explanation": "The correct answer is B because in the 100-250°C tempering range, the primary transformation is the decomposition of martensite into a more stable structure. Option A is incorrect as bainite forms during cooling, not tempering. Option C is a plausible trap as epsilon-carbides do form, but they are a result of martensite decomposition. Option D exploits confusion with higher temperature tempering processes where recrystallization occurs.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4255, "question": "The steady-state diffusion flux through a metal plate is 5.4 × 10^{-10}kg / m^{2}-s at a temperature of 727^{\\circ} C (1000 K) and when the concentration gradient is -350kg / m^{4}. Calculate the diffusion flux at 1027^{\\circ} C(1300 K) for the same concentration gradient and assuming an activation energy for diffusion of 125,000 J/ mol.", "answer": "the diffusion flux at 1027^{\\circ} C (1300 k) is 1.74 × 10^{-8} \\mathrm{kg/m^{2}-s}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解扩散通量，涉及温度变化和浓度梯度的计算，答案也是具体的数值结果。 | 知识层次: 题目涉及多步计算和概念关联，需要应用扩散通量的公式，并考虑温度对扩散系数的影响，同时需要理解阿伦尼乌斯方程的应用。虽然不涉及复杂的推理分析或机理解释，但需要综合运用多个知识点进行计算。 | 难度: 在选择题中属于中等难度，需要理解扩散通量的概念、温度对扩散系数的影响，并应用阿伦尼乌斯方程进行多步计算。虽然题目提供了部分参数，但仍需综合运用多个物理概念和数学计算才能得出正确答案。", "convertible": true, "correct_option": "1.74 × 10^{-8} kg/m^{2}-s", "choice_question": "The steady-state diffusion flux through a metal plate is 5.4 × 10^{-10} kg/m^{2}-s at a temperature of 727°C (1000 K) and when the concentration gradient is -350 kg/m^{4}. Calculate the diffusion flux at 1027°C (1300 K) for the same concentration gradient and assuming an activation energy for diffusion of 125,000 J/mol. The diffusion flux at 1027°C (1300 K) is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.74 × 10^{-8} kg/m^{2}-s", "B": "5.4 × 10^{-10} kg/m^{2}-s", "C": "3.21 × 10^{-9} kg/m^{2}-s", "D": "9.87 × 10^{-7} kg/m^{2}-s" }, "correct_answer": "A", "explanation": "正确答案A是通过Arrhenius方程正确计算得出的扩散通量值。干扰项B是原始温度下的通量值，设计目的是利用AI对温度变化影响扩散系数的直觉判断不足。干扰项C是一个中间值，模拟了线性外推的错误计算方式。干扰项D是一个数量级过大的值，利用了可能忽略对数比例关系的计算错误。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 692, "question": "In the wetting of solid-liquid interfaces, increasing the roughness of the solid surface necessarily improves wetting.", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（对错），答案以×表示错误，符合判断题的特征。 | 知识层次: 题目考查对固体-液体界面润湿现象中表面粗糙度影响的基本概念的理解，属于基础概念的记忆和简单应用。 | 难度: 在选择题型中，此题属于基本概念正误判断。题目仅考察对固体-液体界面润湿基本原理的记忆，即表面粗糙度并不必然改善润湿性。不需要理解复杂概念或进行多步骤分析，只需识别陈述是否正确。属于最基础的概念判断题。", "convertible": true, "correct_option": "×", "choice_question": "In the wetting of solid-liquid interfaces, increasing the roughness of the solid surface necessarily improves wetting.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "For all metal alloys, increasing the temperature will always lead to an increase in electrical conductivity.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While increasing temperature generally increases conductivity in pure metals due to enhanced electron mobility, this is not universally true for all metal alloys. Some alloys exhibit negative temperature coefficients of resistivity where conductivity decreases with temperature. The statement's use of 'all' and 'always' makes it incorrect, as alloy behavior depends on composition and electronic structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3137, "question": "Briefly explain the differences between twinning and slip in the plastic deformation process", "answer": "Twinning causes a uniform shear in a portion of the crystal, while slip is concentrated on the slip plane; twinning changes the orientation of a portion of the crystal, whereas slip does not alter the crystal orientation; the twinning elements are usually different from the slip systems; the critical shear stress for twinning is much higher than that for slip, the stress-strain curve for twinning is serrated, while that for slip is smooth; the deformation rate of twinning is far higher than that of slip.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释孪生和滑移在塑性变形过程中的差异，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释孪生和滑移在塑性变形过程中的差异，涉及多个方面的比较（如剪切分布、晶体取向变化、临界剪切应力等），需要综合理解和分析不同变形机制的异同点，属于中等应用层次的知识。 | 难度: 在选择题型内，该题目属于较高难度。题目要求考生不仅理解\"twinning\"和\"slip\"这两个塑性变形过程的基本概念，还需要从多个角度（包括变形机制、晶体取向变化、临界剪切应力、应力-应变曲线特征以及变形速率）进行对比分析。正确选项包含了5个不同的比较维度，每个维度都需要准确的概念理解和应用能力。这种多角度分析的要求超出了简单记忆或单一概念理解的层次，需要考生能够综合运用所学知识进行系统比较，因此在选择题型内属于等级4的难度。", "convertible": true, "correct_option": "Twinning causes a uniform shear in a portion of the crystal, while slip is concentrated on the slip plane; twinning changes the orientation of a portion of the crystal, whereas slip does not alter the crystal orientation; the twinning elements are usually different from the slip systems; the critical shear stress for twinning is much higher than that for slip, the stress-strain curve for twinning is serrated, while that for slip is smooth; the deformation rate of twinning is far higher than that of slip.", "choice_question": "Which of the following accurately describes the differences between twinning and slip in the plastic deformation process?", "conversion_reason": "The answer is a standard explanation of the differences between twinning and slip, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Twinning involves atomic displacements that produce a mirror image of the crystal structure, while slip preserves the original orientation; twinning requires higher stress than slip but results in lower strain per deformation event", "B": "Both twinning and slip occur through dislocation motion, but twinning involves partial dislocations while slip uses perfect dislocations; twinning produces larger strain increments than slip at comparable stress levels", "C": "Slip systems are determined by the Burgers vector and slip plane, whereas twinning systems depend on the twin plane and shear direction; twinning can accommodate strain in directions where slip systems are inactive", "D": "Twinning creates new grain boundaries while slip does not; the critical resolved shear stress for twinning is typically lower than for slip due to the cooperative nature of atomic movements" }, "correct_answer": "A", "explanation": "Correct answer A accurately describes that twinning creates a mirror image orientation change while slip preserves orientation, and correctly notes the higher stress requirement for twinning. Option B is incorrect because twinning doesn't necessarily produce larger strains than slip. Option C contains partial truths but misleadingly suggests twinning systems are fundamentally different from slip systems. Option D reverses the critical stress relationship and incorrectly states twinning creates grain boundaries. The key traps are: B's plausible-sounding dislocation comparison, C's oversimplified system differentiation, and D's stress relationship reversal which exploits common misconceptions about deformation mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3229, "question": "What is called fracture toughness K_IC?", "answer": "K_IC is the critical value of the stress intensity factor for a Type I crack, representing the fracture toughness in terms of stress intensity factor under linear elastic conditions, with the unit MPa*m^0.5.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"fracture toughness K_IC\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查对断裂韧性K_IC这一基本概念的定义和单位记忆，属于基础概念的记忆和理解层面，不涉及复杂应用或分析。 | 难度: 该题目要求考生理解和记忆\"fracture toughness K_IC\"的定义及其关键特征（如临界应力强度因子、I型裂纹、线弹性条件等），属于概念解释和描述的层次。虽然涉及多个专业术语，但在选择题型中只需识别正确描述，不需要进行复杂的概念体系阐述或分析比较，因此属于中等难度。", "convertible": true, "correct_option": "K_IC is the critical value of the stress intensity factor for a Type I crack, representing the fracture toughness in terms of stress intensity factor under linear elastic conditions, with the unit MPa*m^0.5.", "choice_question": "Which of the following best defines fracture toughness K_IC?", "conversion_reason": "The answer is a standard definition of a technical term, which can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "K_IC is the critical value of the stress intensity factor for a Type I crack, representing the fracture toughness in terms of stress intensity factor under linear elastic conditions, with the unit MPa*m^0.5", "B": "K_IC is the maximum elastic strain energy density a material can absorb before fracture, measured in J/m^3", "C": "K_IC is the critical stress required to propagate a crack under plane strain conditions, expressed in MPa", "D": "K_IC is the ratio of applied stress to crack length at which fast fracture occurs, dimensionless" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines K_IC with all key elements: critical stress intensity factor, Type I crack, linear elastic conditions, and correct units. Option B confuses fracture toughness with strain energy density (a related but distinct concept). Option C incorrectly describes it as a critical stress rather than stress intensity factor. Option D introduces a dimensionless ratio misconception, ignoring the √m dimension in stress intensity factors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4930, "question": "Visible light having a wavelength of 5 x 10^-7 m appears green. Compute the frequency of a photon of this light.", "answer": "the frequency of the photon is 6 x 10^14 s^-1.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（使用光速公式 c = λν）来求解光子的频率，答案是一个具体的数值结果。 | 知识层次: 题目需要应用基本公式（频率=光速/波长）进行简单计算，属于直接套用公式的范畴，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需要直接应用光速公式（c = λν）进行简单计算，属于单一公式直接计算的类型。学生只需记住公式并代入已知数值即可得出答案，无需复杂的推理或多步骤运算。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "6 x 10^14 s^-1", "choice_question": "Visible light having a wavelength of 5 x 10^-7 m appears green. What is the frequency of a photon of this light?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6 x 10^14 s^-1", "B": "1.5 x 10^15 s^-1", "C": "3 x 10^8 m/s", "D": "1.67 x 10^-15 s" }, "correct_answer": "A", "explanation": "正确答案A通过c=λν公式计算得出，其中c为光速(3x10^8 m/s)，λ为波长(5x10^-7 m)。干扰项B错误地将波长倒数作为频率(1/λ)，忽略了光速因素。干扰项C给出的是光速值而非频率，利用单位混淆陷阱。干扰项D是波长的倒数但单位错误，制造数值接近但概念完全错误的陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1123, "question": "If the carbon content is 0.8% in high-carbon steel with an original grain size of 0.05mm, calculate the grain size and its growth value after holding at 760‰ for 1 hour. The formula D^(1/n) - D0^(1/n) = c t can be used for calculation, where at 760‰, the constant c is 6×10^(-16), n is 0.1, D and D0 are grain sizes in mm, and t is time in minutes.", "answer": "Holding at 760‰ for 1h: D^(1/0.1) - D0^(1/0.1) = 6×10^(-16)×60; D^10 - D0^10 = 3.6×10^(-14); D^10 = 3.6×10^(-14) + D0^10 = 0.05^10 + 3.6×10^(-14) = 9.77×10^(-14) + 3.6×10^(-14) = 13.4×10^(-14); D = (13.4×10^(-14))^(1/10) = 5.16×10^(-2) mm = 0.0516mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求使用给定的公式进行数值计算，最终得出具体的数值结果（0.0516mm），这符合计算题的特征。解答过程涉及公式应用和数值运算，不需要选择或判断，也不需要文字论述。 | 知识层次: 题目需要进行多步计算，包括公式的代入和求解，涉及对晶粒生长公式的理解和应用。虽然计算过程较为直接，但需要一定的综合分析能力和对公式中各参数的理解。 | 难度: 在选择题中属于中等偏上难度，需要理解晶粒生长公式并正确代入数值进行多步计算。题目涉及指数运算和单位转换，要求考生具备综合应用公式和计算的能力。虽然提供了公式和常数，但计算步骤较多且需要精确处理小数值，属于综合性计算问题。", "convertible": true, "correct_option": "0.0516mm", "choice_question": "If the carbon content is 0.8% in high-carbon steel with an original grain size of 0.05mm, what is the grain size after holding at 760‰ for 1 hour? Use the formula D^(1/n) - D0^(1/n) = c t, where at 760‰, the constant c is 6×10^(-16), n is 0.1, D and D0 are grain sizes in mm, and t is time in minutes.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0516mm", "B": "0.0528mm", "C": "0.0492mm", "D": "0.0504mm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.0516mm) as calculated using the given grain growth formula with n=0.1. Option B (0.0528mm) is designed to exploit the common mistake of using n=2 (classical grain growth exponent) instead of the given n=0.1. Option C (0.0492mm) traps those who might incorrectly assume grain shrinkage. Option D (0.0504mm) appears plausible by using a linear approximation of the growth formula, which is invalid for this nonlinear system.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3964, "question": "Calculate the value of flexural strength for this test given a cylindrical specimen of aluminum oxide with a radius of 2.5mm (0.10 in.) and a support point separation distance of 30mm (1.2 in.) when a load of 620 N (140 lbf) is applied.", "answer": "The flexural strength for this test is 379 MPa (53,500 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的参数（圆柱形试样的半径、支撑点间距和施加的载荷）计算弯曲强度，需要使用相关公式进行数值计算。答案也是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要考查对弯曲强度公式的直接应用和简单计算，不需要多步推理或综合分析，属于基本公式套用和单位换算的范畴。 | 难度: 在选择题型内，该题目属于简单公式应用计算。虽然需要应用弯曲强度的基本公式，但题目已经提供了所有必要的参数（半径、支撑点距离、载荷），只需直接套用公式进行计算即可。不需要多个公式组合或复杂推导，属于选择题型中中等偏下的难度。", "convertible": true, "correct_option": "379 MPa (53,500 psi)", "choice_question": "What is the flexural strength for a test given a cylindrical specimen of aluminum oxide with a radius of 2.5mm (0.10 in.) and a support point separation distance of 30mm (1.2 in.) when a load of 620 N (140 lbf) is applied?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "379 MPa (53,500 psi)", "B": "248 MPa (36,000 psi)", "C": "413 MPa (60,000 psi)", "D": "310 MPa (45,000 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the flexural strength formula for cylindrical specimens: σ = (8FL)/(πd³), where F=620N, L=30mm, d=5mm. Option B is a common error from using diameter instead of radius in the formula. Option C mimics the tensile strength of alumina (a cognitive bias trap). Option D is a miscalculation using the wrong exponent in the formula (professional intuition trap).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 410, "question": "Eutectoid transformation", "answer": "Eutectoid transformation: The process in which a single solid phase simultaneously precipitates two new solid phases with different compositions and crystal structures is called eutectoid transformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Eutectoid transformation\"进行文字解释和论述，答案提供了详细的定义说明，符合简答题的特征。 | 知识层次: 题目考查对eutectoid transformation这一基本概念的定义和记忆，属于材料科学中相变的基础知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对\"Eutectoid transformation\"基本定义的记忆，属于最基础的概念性知识。题目要求识别正确描述该术语定义的选项，不需要进行概念解释或复杂分析，符合等级1\"基本定义简答\"的标准。选择题型中此类直接考察定义的题目属于最低难度级别。", "convertible": true, "correct_option": "The process in which a single solid phase simultaneously precipitates two new solid phases with different compositions and crystal structures is called eutectoid transformation.", "choice_question": "Which of the following best describes eutectoid transformation?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by asking for the best description of the term.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The process in which a single solid phase simultaneously precipitates two new solid phases with different compositions and crystal structures", "B": "The transformation of a liquid phase into two different solid phases upon cooling", "C": "The decomposition of a supersaturated solid solution into two phases with the same crystal structure", "D": "The diffusionless transformation of a high-temperature phase into a martensitic structure" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines eutectoid transformation as the simultaneous precipitation of two distinct solid phases from a single parent phase. Option B incorrectly describes a eutectic (not eutectoid) transformation involving liquid phase. Option C describes spinodal decomposition, not eutectoid. Option D describes martensitic transformation which is diffusionless, unlike the diffusion-dependent eutectoid process. The distractors exploit common confusions between eutectoid/eutectic transformations and other phase transformation mechanisms in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3674, "question": "The strength of titanium is found to be 65,000 psi when the grain size is 17 x 10^-6 m and 82,000 psi when the grain size is 0.8 x 10^-6 m. Determine the strength of the titanium when the grain size is reduced to 0.2 x 10^-6 m.", "answer": "the strength of the titanium when the grain size is reduced to 0.2 x 10^-6 m is 103,670 psi.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的数据和公式进行计算，以确定钛在特定晶粒尺寸下的强度。答案是一个具体的数值结果，需要通过数学运算得出。 | 知识层次: 题目需要应用Hall-Petch公式进行多步计算，涉及不同晶粒尺寸下的强度关系分析，需要理解晶粒尺寸对材料强度的影响机制，并进行数值计算和结果预测。 | 难度: 在选择题中属于中等偏上难度，需要应用Hall-Petch关系进行多步计算，涉及反推材料常数和预测新条件下的强度值。虽然选择题提供了正确选项，但仍需理解晶粒尺寸与强度的非线性关系，并执行两次数据点拟合才能得出答案。这超出了简单概念回忆或单步计算的难度，但尚未达到需要处理复杂多变量或非常规公式的等级4水平。", "convertible": true, "correct_option": "103,670 psi", "choice_question": "The strength of titanium is found to be 65,000 psi when the grain size is 17 x 10^-6 m and 82,000 psi when the grain size is 0.8 x 10^-6 m. Determine the strength of the titanium when the grain size is reduced to 0.2 x 10^-6 m:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "103,670 psi", "B": "92,500 psi (Hall-Petch slope miscalculation)", "C": "78,300 psi (linear extrapolation error)", "D": "115,000 psi (ignoring saturation effect)" }, "correct_answer": "A", "explanation": "Correct answer uses proper Hall-Petch relationship (σ = σ₀ + k/√d). Option B miscalculates the slope k by using incorrect units. Option C makes a naive linear extrapolation error. Option D ignores the grain size strengthening saturation effect that occurs at very small grain sizes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1408, "question": "In interstitial solid solutions, by what mechanism do solute atoms diffuse?", "answer": "In interstitial solid solutions, solute atoms diffuse by the interstitial mechanism.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述扩散机制，答案提供了详细的解释，符合简答题的特征。 | 知识层次: 题目考查对间隙固溶体中溶质原子扩散机制的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即\"间隙固溶体中溶质原子的扩散机制\"。正确选项直接给出了定义性的答案，不需要任何解释或分析步骤。这属于最基本的概念记忆题，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "the interstitial mechanism", "choice_question": "In interstitial solid solutions, by what mechanism do solute atoms diffuse?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial mechanism", "B": "Vacancy mechanism", "C": "Dislocation pipe diffusion", "D": "Grain boundary diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because in interstitial solid solutions, solute atoms occupy the spaces between solvent atoms and diffuse by moving through these interstitial sites. Option B is incorrect because vacancy mechanism applies to substitutional diffusion where atoms exchange with vacancies. Option C is a plausible but incorrect choice as dislocation pipes can enhance diffusion but are not the primary mechanism. Option D is incorrect because grain boundaries are fast diffusion paths but not the fundamental mechanism for interstitial diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3113, "question": "The active layer and passive layer of a thermostatic bimetal strip are respectively (1). A. Constant expansion alloy and high expansion alloy B. High expansion alloy and constant expansion alloy C. Constant expansion alloy and low expansion alloy D. High expansion alloy and low expansion alloy", "answer": "(1)D", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且提供了四个选项供选择，符合选择题的特征。 | 知识层次: 题目考查对热双金属片主动层和被动层材料分类的基础概念记忆，属于定义和分类的基本原理记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然考察的是基础概念记忆（热双金属片的主动层和被动层材料），但需要考生区分高膨胀合金和低膨胀合金的概念，并进行简单配对。相比纯粹的定义复述（等级1），此题需要一定的概念理解和材料特性辨析能力，但不需要复杂的分析过程（等级3）。正确选项D的区分度主要体现在对\"高/低膨胀\"这一组对立概念的掌握上。", "convertible": true, "correct_option": "D. High expansion alloy and low expansion alloy", "choice_question": "The active layer and passive layer of a thermostatic bimetal strip are respectively", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Martensite and retained austenite", "B": "Pearlite and ferrite", "C": "Bainite and cementite", "D": "Austenite and martensite" }, "correct_answer": "D", "explanation": "The correct answer is D because in shape memory alloys, the reversible phase transformation between austenite (high-temperature phase) and martensite (low-temperature phase) enables the shape memory effect. Option A is incorrect because retained austenite does not participate in the transformation. Option B is incorrect as pearlite and ferrite are equilibrium phases in steels, not shape memory alloys. Option C is incorrect because bainite is a non-equilibrium phase that does not exhibit shape memory behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3954, "question": "For a bronze alloy, the stress at which plastic deformation begins is 277 MPa and the modulus of elasticity is 117 GPa. What is the maximum load that may be applied to a specimen having a cross-sectional area of 327 mm^2 without plastic deformation?", "answer": "the maximum load that may be applied without plastic deformation is 86,700 N.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（应力、弹性模量和横截面积的关系）来求解最大载荷，答案是一个具体的数值结果。 | 知识层次: 题目涉及基本的应力计算和弹性模量的概念，只需要应用简单的公式（应力=力/面积）进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（应力=力/面积）进行计算，无需组合多个公式或进行复杂的概念分析。解题步骤简单，属于基础级别的难度。", "convertible": true, "correct_option": "86,700 N", "choice_question": "For a bronze alloy, the stress at which plastic deformation begins is 277 MPa and the modulus of elasticity is 117 GPa. What is the maximum load that may be applied to a specimen having a cross-sectional area of 327 mm^2 without plastic deformation?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "86,700 N", "B": "90,500 N (using elastic modulus instead of yield stress)", "C": "277,000 N (ignoring unit conversion from mm² to m²)", "D": "38,100 N (incorrectly applying shear modulus formula)" }, "correct_answer": "A", "explanation": "The correct answer is calculated by multiplying the yield stress (277 MPa) by the cross-sectional area (327 mm²) with proper unit conversion. Option B is a cognitive bias trap that uses the elastic modulus value instead of yield stress. Option C exploits unit conversion negligence by directly multiplying stress and area without converting mm² to m². Option D is a professional intuition trap that incorrectly applies shear modulus calculations to a tensile loading scenario.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2667, "question": "In indium with a tetragonal structure, the relative atomic mass A_r=114.82, atomic radius r=0.1625 nm, lattice constants a=0.3252 nm, c=0.4946 nm, and density ρ=7.286 g/cm³. What is the packing fraction of In?", "answer": "K=(2×(4/3)πr³)/(a²c)=(2×(4/3)π(0.1625)^3)/((0.3252)^2×0.4946)=0.6873.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铟的堆积分数，答案是一个具体的数值计算结果，解答过程涉及使用给定的参数和公式进行运算。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过给定的原子半径和晶格常数计算堆积分数。虽然需要理解堆积分数的概念，但整体过程是直接套用公式进行计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用体积分数公式，但解题步骤明确且直接，仅需代入给定数据进行计算，无需复杂的推理或多步骤组合。属于基础知识的直接应用层次。", "convertible": true, "correct_option": "0.6873", "choice_question": "In indium with a tetragonal structure, the relative atomic mass A_r=114.82, atomic radius r=0.1625 nm, lattice constants a=0.3252 nm, c=0.4946 nm, and density ρ=7.286 g/cm³. What is the packing fraction of In?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.6873", "B": "0.7231", "C": "0.6542", "D": "0.7048" }, "correct_answer": "A", "explanation": "The correct answer is A (0.6873) because it is calculated by first determining the number of atoms per unit cell (2 atoms for tetragonal In), then calculating the volume of atoms (2 × (4/3)πr³) divided by the unit cell volume (a² × c). Option B (0.7231) mimics the FCC packing fraction to exploit AI's tendency to default to common crystal structures. Option C (0.6542) uses an incorrect atomic radius assumption (0.157 nm) to catch unit conversion errors. Option D (0.7048) is derived from a miscalculation using the density formula without proper volume consideration, targeting AI's potential oversight in multi-step calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4661, "question": "Indium (In) has a tetragonal unit cell for which the a and c lattice parameters are 0.459 and 0.495 nm, respectively. If the atomic packing factor and atomic radius are 0.693 and 0.1625 nm, respectively, determine the number of atoms in each unit cell.", "answer": "4.0 atoms/unit cell", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的晶格参数、原子堆积因子和原子半径进行数值计算，最终确定每个晶胞中的原子数。解答过程需要应用相关公式和计算步骤，答案是一个具体的数值（4.0 atoms/unit cell），符合计算题的特征。 | 知识层次: 题目需要应用晶格参数、原子堆积因子和原子半径等多重概念，进行多步计算和综合分析，以确定每个晶胞中的原子数。这超出了简单应用的范围，但尚未达到复杂分析或高级综合的层次。 | 难度: 在选择题中属于中等偏上难度，需要结合晶格参数、原子堆积因子和原子半径进行多步计算，并理解各参数之间的关系。虽然题目提供了所有必要数据，但解题过程涉及单位晶胞体积、原子总体积与原子堆积因子的关联计算，需要一定的综合分析能力。相比单纯的概念记忆题，该题对计算和逻辑推理的要求更高，但尚未达到复杂多变量计算的等级4难度。", "convertible": true, "correct_option": "4.0 atoms/unit cell", "choice_question": "Indium (In) has a tetragonal unit cell for which the a and c lattice parameters are 0.459 and 0.495 nm, respectively. If the atomic packing factor and atomic radius are 0.693 and 0.1625 nm, respectively, determine the number of atoms in each unit cell.", "conversion_reason": "计算题的答案是确定的数值，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.0 atoms/unit cell", "B": "2.0 atoms/unit cell", "C": "6.0 atoms/unit cell", "D": "8.0 atoms/unit cell" }, "correct_answer": "A", "explanation": "The correct answer is A (4.0 atoms/unit cell) because the atomic packing factor (APF) calculation for a tetragonal cell requires solving APF = (number of atoms × volume of one atom) / unit cell volume. Given APF=0.693, r=0.1625 nm, a=0.459 nm, c=0.495 nm, the calculation yields exactly 4 atoms. Option B (2.0) is a common mistake from misapplying the simple cubic formula. Option C (6.0) exploits confusion with hexagonal close packing. Option D (8.0) is a trap for those who assume body-centered tetragonal without proper calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3974, "question": "During the recovery of a cold-worked material, is some of the internal strain energy relieved?", "answer": "Some of the internal strain energy is relieved.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（\"is some of the internal strain energy relieved?\"），而答案直接给出了判断结果（\"Some of the internal strain energy is relieved.\"）。这符合判断题的特征，即对陈述的真伪进行判断。 | 知识层次: 题目考查冷加工材料恢复过程中内应变能变化的基本概念，属于对基本原理的记忆和理解。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即冷加工材料恢复过程中内部应变能的释放情况。正确选项直接陈述了基本原理，无需复杂理解或分析，属于最基本的概念正误判断。", "convertible": true, "correct_option": "Some of the internal strain energy is relieved.", "choice_question": "During the recovery of a cold-worked material, is some of the internal strain energy relieved?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All cold-worked materials will completely lose their internal strain energy during the recovery stage of annealing.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is a false statement due to the absolute term 'all' and 'completely'. While recovery does relieve some internal strain energy, it typically only partially reduces the stored energy. Complete elimination of strain energy usually requires reaching the recrystallization stage. The statement oversimplifies the complex recovery process where dislocations rearrange but aren't fully eliminated.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2922, "question": "In cubic crystals, the (110) and (211) planes belong to the same zone axis.", "answer": "D", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从选项中选择正确答案，答案以选项形式给出（D） | 知识层次: 题目需要理解立方晶体中晶面与晶带轴的关系，并能够判断不同晶面是否属于同一晶带轴。这涉及到对晶体几何学基本原理的应用，以及综合分析不同晶面指数的关系，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。需要掌握立方晶体中晶面指数和晶带轴的概念，并能进行多步计算和综合分析。题目要求判断(110)和(211)晶面是否属于同一晶带轴，这需要运用晶带定律进行计算验证，涉及多个概念的综合应用和较复杂的分析过程。在选择题型内，这种需要多步计算和概念关联的题目相对难度较高。", "convertible": true, "correct_option": "D", "choice_question": "In cubic crystals, the (110) and (211) planes belong to the same zone axis.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The zone axis is [111] because both planes contain this direction", "B": "The zone axis is [110] as it's the simplest common direction for cubic systems", "C": "These planes cannot belong to the same zone axis due to different Miller indices", "D": "The zone axis is [1-10] as determined by the cross product of the plane normals" }, "correct_answer": "D", "explanation": "The correct answer is D because the zone axis is indeed [1-10] when calculated using the cross product method for cubic crystals. Option A exploits the common misconception that high-symmetry directions like [111] must be involved. Option B preys on the intuition that lower-index directions are more likely. Option C creates false doubt about fundamental crystallographic principles. All three incorrect options leverage different types of cognitive biases in materials science reasoning.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 493, "question": "In the cesium chloride structure, chlorine occupies the corner positions and the body center position of the cube, so its structure type is body-centered lattice.", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（关于氯化铯结构的描述），并要求判断其正确性（答案用×表示错误），这符合判断题的特征。 | 知识层次: 题目考查对晶体结构类型的基本概念记忆和理解，涉及简单的定义和分类知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆并识别氯化铯结构的正确描述即可。题目直接考察对体心晶格定义的理解，无需复杂分析或推理步骤，属于最基础难度等级。", "convertible": true, "correct_option": "×", "choice_question": "In the cesium chloride structure, chlorine occupies the corner positions and the body center position of the cube, so its structure type is body-centered lattice.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials will eventually crystallize given sufficient time at temperatures below their glass transition temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement contains multiple traps. First, the use of 'all' is problematic - some amorphous materials like certain glasses are kinetically stable and may never crystallize. Second, crystallization typically occurs above (not below) the glass transition temperature where molecular mobility increases. The statement combines these two misconceptions to create a particularly challenging question that tests understanding of amorphous material stability and crystallization kinetics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2274, "question": "A steel wire with a diameter of 0.89 mm has σ_ss=980 MPa and σ_sb=1,130 MPa. Another aluminum alloy has σ_as=255 MPa and σ_ab=400 MPa. Their densities are known to be ρ_s=7.85 g/cm³ and ρ_a=2.7 g/cm³, respectively. What if they do not break?", "answer": "σ_sb=φ_max/A_s=1,130, σ_ab=φ_max/A_a=400. From the above two equations, A_s/A_a=400/1,130. A_a=2.825A_s. m_a/m_s=(2.825×2.7)/(1×7.85)=0.97. 0.97-1=-0.03=-3%. That is, the aluminum wire is 3% lighter than the steel wire.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目提供了具体的材料参数和密度，要求通过公式计算比较两种材料的重量差异，解答过程涉及数值计算和公式应用。 | 知识层次: 题目涉及多步计算和概念关联，需要综合运用材料的力学性能和密度数据进行计算，并进行比较分析。虽然不涉及复杂的推理或机理解释，但需要理解和应用多个参数之间的关系。 | 难度: 在选择题中属于中等偏上难度，需要理解材料的强度、密度等基本概念，并进行多步计算和比较分析。题目涉及两个不同材料的性能参数，要求考生能够正确应用公式计算面积比和质量比，最后得出百分比差异。虽然题目提供了正确选项，但解题过程需要综合运用多个知识点和计算步骤，属于综合性计算问题。", "convertible": true, "correct_option": "the aluminum wire is 3% lighter than the steel wire", "choice_question": "A steel wire with a diameter of 0.89 mm has σ_ss=980 MPa and σ_sb=1,130 MPa. Another aluminum alloy has σ_as=255 MPa and σ_ab=400 MPa. Their densities are known to be ρ_s=7.85 g/cm³ and ρ_a=2.7 g/cm³, respectively. If they do not break, which of the following statements is correct?", "conversion_reason": "The original calculation question has a specific and clear answer that can be converted into a single-choice format. The correct option is derived from the conclusion of the calculation.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The aluminum wire can support 40% more load per unit weight than steel when both operate at their yield strengths", "B": "The steel wire has a higher specific strength (σ/ρ) in both yield and ultimate conditions", "C": "The aluminum alloy exhibits better strain hardening capability based on the given strength ratios", "D": "Both materials will show identical weight efficiency when designed for equal stiffness" }, "correct_answer": "A", "explanation": "The correct answer is A because when calculating specific strength (strength/density) at yield points: (255/2.7)/(980/7.85)=1.40, showing 40% advantage. B is wrong as aluminum has higher specific strength at yield (94.4 vs 124.8 MPa·cm³/g). C misleads by comparing strength ratios without considering actual hardening behavior. D is a stiffness trap, confusing strength with elastic modulus which isn't provided.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1685, "question": "How does the influence of slip and twinning on crystal orientation relationships differ?", "answer": "The twinning process alters the crystal orientation relationship. The slip process does not change the crystal orientation relationship.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述滑移和孪生对晶体取向关系的不同影响，答案提供了文字解释而非选择、判断或计算。 | 知识层次: 题目要求比较滑移和孪生对晶体取向关系的影响，涉及对两种变形机制的理解和对比分析，需要将概念关联并进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解晶体取向关系的基本概念，并能够区分滑移和孪生两种变形机制对晶体取向的不同影响。题目要求考生综合分析两种机制的差异，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "The twinning process alters the crystal orientation relationship. The slip process does not change the crystal orientation relationship.", "choice_question": "How does the influence of slip and twinning on crystal orientation relationships differ?", "conversion_reason": "The answer is a clear and concise statement that can be directly used as a correct option in a multiple-choice question. The original question can be kept as is for the multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Twinning creates mirror symmetry across the twin plane while slip preserves the original orientation", "B": "Both slip and twinning equally modify the overall crystal orientation relationship", "C": "Slip causes greater orientation change due to dislocation accumulation while twinning only affects local regions", "D": "Neither process significantly alters orientation relationships as they both operate through shear deformation" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the fundamental difference: twinning introduces new orientation relationships through mirror symmetry, while slip merely displaces material without changing orientation. Option B exploits the common AI tendency to assume similar effects from related deformation mechanisms. Option C reverses the actual effects, playing on the intuition that dislocation accumulation should cause more change. Option D creates a false equivalence by focusing only on the shared shear characteristic while ignoring their fundamentally different consequences for crystal orientation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4873, "question": "What are the characteristics of die casting technique?", "answer": "For die casting, a permanent mold is used, casting rates are high, the molten metal is forced into the mold under pressure, a two-piece mold is used, and small pieces are normally cast.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释die casting technique的特征，答案提供了详细的文字描述和论述，符合简答题的特点 | 知识层次: 题目考查对压铸技术基本特征的理解和记忆，属于基础概念层次 | 难度: 该题目属于选择题型，要求考生识别并选择出压铸技术的特点。虽然涉及多个特点（永久模具、高铸造率、压力下注入熔融金属、两件式模具、通常铸造小件），但这些都属于基础概念记忆层次的定义和描述，不需要复杂的分析或推理。在选择题型中，这属于中等难度，因为需要考生对压铸技术有基本的理解和记忆，但不需要深入的概念体系阐述或复杂比较。", "convertible": true, "correct_option": "For die casting, a permanent mold is used, casting rates are high, the molten metal is forced into the mold under pressure, a two-piece mold is used, and small pieces are normally cast.", "choice_question": "Which of the following describes the characteristics of die casting technique?", "conversion_reason": "The answer is a standard description of the die casting technique, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Permanent mold, high casting rates, molten metal forced under pressure, two-piece mold, small castings", "B": "Expendable mold, low casting rates, gravity-fed, single-piece mold, large castings", "C": "Permanent mold, medium casting rates, vacuum-assisted filling, multi-piece mold, medium castings", "D": "Semi-permanent mold, variable casting rates, centrifugal force filling, modular mold, all size castings" }, "correct_answer": "A", "explanation": "Option A correctly describes die casting characteristics: permanent metal molds, high production rates due to rapid solidification, pressurized injection (typically 10-140MPa), two-part molds for part ejection, and suitability for small-to-medium parts (typically <25kg). Option B incorrectly describes sand casting attributes. Option C mixes vacuum casting elements with die casting. Option D combines features from different specialized casting methods, creating a plausible-sounding but incorrect hybrid process description that could mislead AI systems relying on pattern matching.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 325, "question": "Calculate the number of atoms in the critical nucleus for copper with a face-centered cubic crystal structure. (a=0.3615nm)", "answer": "The volume of the critical nucleus V = (4/3) × π × (γ*)³ = (4/3) × 3.14 × (1.087 × 10⁻⁷)³ = 5.39 × 10⁻²¹ cm³. The unit cell volume V_cell = a³ = (0.3615 × 10⁻⁷)³ = 4.72 × 10⁻²³ cm³. The number of unit cells N = V / V_cell = 5.39 × 10⁻²¹ / 4.72 × 10⁻²³ ≈ 114. The number of atoms in a face-centered cubic unit cell is 4, so the number of atoms in the critical nucleus = 114 × 4 = 456.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及原子数量、体积等具体计算步骤，答案也以数值结果呈现。 | 知识层次: 题目需要进行多步计算，包括临界核体积的计算、晶胞体积的计算以及单位晶胞内原子数的应用。虽然涉及的概念和公式较为基础，但需要将这些概念和公式综合运用，进行多步推导和计算，属于中等应用层次。 | 难度: 在选择题型中，该题目属于高难度等级。题目要求进行多步骤的复杂计算，包括临界核体积、晶胞体积的计算，以及单位晶胞内原子数的转换。此外，还需要理解面心立方晶体结构的基本概念，并将这些概念综合应用到实际问题中。这种题目不仅考察了基础知识的掌握，还要求考生具备较强的计算能力和综合分析能力，因此在选择题型中属于复杂多变量计算的高难度题目。", "convertible": true, "correct_option": "456", "choice_question": "Calculate the number of atoms in the critical nucleus for copper with a face-centered cubic crystal structure (a=0.3615nm).", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "456", "B": "128", "C": "216", "D": "512" }, "correct_answer": "A", "explanation": "The correct answer is A (456) because it accounts for the face-centered cubic structure and the given lattice parameter (a=0.3615nm) to calculate the critical nucleus size. Option B (128) is a common error from assuming simple cubic packing. Option C (216) is a trap for those who incorrectly calculate based on body-centered cubic structure. Option D (512) exploits the tendency to round up to the nearest power of 2 without proper structural consideration.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3391, "question": "A batch of carbon tool steel workpieces were found to have insufficient hardness after quenching. It is estimated that either surface decarburization occurred or the cooling rate during quenching was too low. How to quickly determine the cause of the problem.", "answer": "Metallographic examination.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来快速确定问题的原因，答案“Metallographic examination”是一个简短的解决方案描述，属于需要文字解释的简答题类型。 | 知识层次: 题目要求通过金相检验来快速确定硬度不足的原因，这需要将金相检验的基本原理与实际问题的分析相结合，属于中等应用层次。虽然金相检验本身是基础概念，但如何将其应用于具体问题的诊断需要一定的综合分析能力，涉及多步思考和概念关联。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及碳工具钢淬火后硬度不足的两个可能原因（表面脱碳或淬火冷却速率过低），要求考生通过金相检验快速确定原因。这需要考生具备材料科学基础知识，能够将金相检验方法与问题原因关联起来，并进行综合分析判断。虽然不需要多步计算，但需要概念关联和综合分析能力，因此在选择题型中属于等级3难度。", "convertible": true, "correct_option": "Metallographic examination", "choice_question": "A batch of carbon tool steel workpieces were found to have insufficient hardness after quenching. It is estimated that either surface decarburization occurred or the cooling rate during quenching was too low. How to quickly determine the cause of the problem?", "conversion_reason": "The answer is a standard term (Metallographic examination) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metallographic examination", "B": "X-ray diffraction analysis", "C": "Measure electrical conductivity", "D": "Perform Rockwell hardness test on multiple surface points" }, "correct_answer": "A", "explanation": { "correct_answer": "Metallographic examination can directly reveal both surface decarburization (through microstructural changes) and insufficient quenching (through martensite formation), making it the most efficient diagnostic method.", "distractors": { "B": "X-ray diffraction is a plausible but inefficient choice - while it can detect decarburization, it cannot assess quenching effectiveness, creating a partial-knowledge trap.", "C": "Electrical conductivity exploits a common misconception - while it correlates with carbon content, it cannot distinguish between bulk composition changes (decarburization) and phase transformations (quenching issues).", "D": "Multiple hardness tests create a 'more data' illusion - while hardness differences might suggest decarburization, they cannot conclusively distinguish it from quenching problems due to overlapping hardness ranges." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2003, "question": "A subgrain boundary is composed of $n$ edge dislocations with a misorientation of $0.057^{\\\\circ}$. Assuming there is no interaction between the dislocations before forming the subgrain boundary, by what factor does the distortion energy change after forming the subgrain boundary (given $R{=}10^{-4}$, $r_{0}=b=10^{-8}$; after forming the subgrain boundary, $$ R=D\\\\approx{\\\\frac{b}{\\\\theta}})?", "answer": "The distortion energy is 0.75 times the original value (indicating that the dislocation energy decreases after forming the subgrain boundary).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及能量变化的计算和给定的参数条件。答案提供了具体的计算结果，表明这是一个需要计算步骤的问题。 | 知识层次: 题目涉及多步计算和概念关联，需要应用位错能量公式和亚晶界形成后的能量变化计算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及位错、亚晶界、畸变能等多个材料科学概念，需要进行多步计算和综合分析。虽然题目提供了部分参数和公式，但仍需要考生具备一定的计算能力和概念关联能力，才能正确评估畸变能的变化。这比简单的概念选择题要复杂，但比需要复杂多变量计算的题目要简单一些。", "convertible": true, "correct_option": "0.75 times the original value", "choice_question": "A subgrain boundary is composed of $n$ edge dislocations with a misorientation of $0.057^{\\circ}$. Assuming there is no interaction between the dislocations before forming the subgrain boundary, by what factor does the distortion energy change after forming the subgrain boundary (given $R{=}10^{-4}$, $r_{0}=b=10^{-8}$; after forming the subgrain boundary, $$ R=D\\approx{\\frac{b}{\\theta}})?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.75 times the original value", "B": "1.33 times the original value", "C": "0.57 times the original value", "D": "Equal to the original value" }, "correct_answer": "A", "explanation": "The correct answer is A because the distortion energy decreases when dislocations form a subgrain boundary due to mutual stress field cancellation. Option B is a cognitive bias trap that reverses the energy change direction. Option C exploits the misorientation angle value (0.057°) as an intuitive but incorrect scaling factor. Option D is a professional intuition trap suggesting no energy change, which would only occur for perfectly random distributions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1522, "question": "After cold plastic deformation, the plasticity and toughness of metal (24)", "answer": "(24) decrease", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释金属在冷塑性变形后的性能变化，需要文字解释和论述，答案形式为简短的文字描述而非选择或判断。 | 知识层次: 题目考查金属冷塑性变形后性能变化的基本概念记忆，属于基础概念记忆性知识，不需要复杂分析或推理。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需记忆金属在冷塑性变形后塑性和韧性的变化趋势（降低）。题目不涉及复杂概念体系或需要解释描述，解题步骤简单直接，属于最基本难度的选择题。", "convertible": true, "correct_option": "decrease", "choice_question": "After cold plastic deformation, the plasticity and toughness of metal:", "conversion_reason": "The answer is a standard term and can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Decrease due to dislocation entanglement and increased defect density", "B": "Increase as strain hardening improves atomic bonding strength", "C": "Remain unchanged as plastic deformation only affects elastic properties", "D": "First increase then decrease due to competing effects of dislocation multiplication and annihilation" }, "correct_answer": "A", "explanation": "The correct answer is A because cold plastic deformation introduces dislocations and defects that impede further plastic flow, reducing toughness. Option B exploits the common misconception that stronger bonding always improves toughness. Option C targets confusion between elastic and plastic properties. Option D creates a complex multi-stage scenario that seems plausible but doesn't reflect the immediate effects of cold working.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 388, "question": "When stretching a single crystal, the slip plane is most prone to slip when it turns to an angle of (14) with the external force axis.", "answer": "(14) 45°", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个具体的角度值作为答案，而不是从多个选项中选择或判断对错，也不需要复杂的计算过程。虽然答案是一个数值，但更侧重于对材料科学原理的理解和应用，属于简答题的范畴。 | 知识层次: 题目考查的是单晶拉伸时滑移面最容易滑动的角度这一基本概念的记忆和理解，属于材料科学中的基础知识点，不需要复杂的应用或分析。 | 难度: 在选择题型中，此题属于基础概念记忆题，仅需回忆单晶拉伸时滑移面最容易滑动的角度这一基本定义即可作答。题目直接给出了正确选项45°，不需要任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "45°", "choice_question": "When stretching a single crystal, the slip plane is most prone to slip when it turns to an angle of _____ with the external force axis.", "conversion_reason": "The answer is a specific numerical value (45°), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "45°", "B": "30°", "C": "60°", "D": "90°" }, "correct_answer": "A", "explanation": "The correct answer is 45° because this angle maximizes the resolved shear stress on the slip plane according to Schmid's law. Option B (30°) is a cognitive bias trap exploiting the common misconception that smaller angles always favor slip. Option C (60°) is a professional intuition trap based on hexagonal crystal symmetry. Option D (90°) is a multi-level verification trap using the maximum normal stress condition which is irrelevant for slip systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4393, "question": "Compare white and nodular cast irons with respect to microstructure.", "answer": "White iron--There are regions of cementite interspersed within pearlite. Nodular cast iron--Nodules of graphite are embedded in a ferrite or pearlite matrix.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较两种铸铁的微观结构，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对白口铸铁和球墨铸铁微观结构的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目要求考生对白口铸铁和球墨铸铁的微观结构进行对比描述。虽然涉及两个不同材料的微观结构特征，但每个特征的描述相对独立且明确（白口铸铁中的渗碳体与珠光体区域、球墨铸铁中的石墨球与铁素体/珠光体基体）。题目属于基础概念记忆层次，不需要复杂的推理或概念体系整合，但比单纯的定义复述（等级1）要求稍高，属于概念解释和描述级别（等级2）。", "convertible": true, "correct_option": "White iron--There are regions of cementite interspersed within pearlite. Nodular cast iron--Nodules of graphite are embedded in a ferrite or pearlite matrix.", "choice_question": "Which of the following correctly compares white and nodular cast irons with respect to microstructure?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "White iron--Cementite forms continuous network; Nodular iron--Graphite spheroids in austenitic matrix", "B": "White iron--Pearlite matrix with dispersed graphite; Nodular iron--Graphite flakes in ferritic matrix", "C": "White iron--There are regions of cementite interspersed within pearlite; Nodular cast iron--Nodules of graphite are embedded in a ferrite or pearlite matrix", "D": "White iron--Martensitic structure with retained austenite; Nodular iron--Bainitic matrix with spheroidal cementite" }, "correct_answer": "C", "explanation": "Correct answer C accurately describes white iron's characteristic cementite regions in pearlite, and nodular iron's graphite nodules in ferrite/pearlite. Option A is wrong by suggesting austenitic matrix (should be ferrite/pearlite) and continuous cementite network. Option B reverses key features (white iron has no graphite, nodular has flakes instead of spheroids). Option D introduces incorrect martensitic and bainitic structures, exploiting heat treatment confusion. The traps leverage: 1) graphite morphology confusion (B), 2) matrix phase misconceptions (A,D), and 3) substituting similar but incorrect microstructures (D).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2501, "question": "What is the crystal structure of diamond?", "answer": "The crystal structure of diamond is FCC with tetrahedral interstices, where carbon atoms are located at the bonding points of the FCC lattice and four non-adjacent tetrahedral interstice positions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释钻石的晶体结构，答案需要详细的文字描述和论述，而不是从选项中选择或简单的对错判断。 | 知识层次: 题目考查对金刚石晶体结构这一基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确理解并描述金刚石的晶体结构（FCC晶格和四面体间隙位置）。这比简单的定义记忆（等级1）要求更高，但尚未达到复杂概念体系阐述（等级3）的程度。考生需要掌握FCC晶格和四面体间隙的基本知识，并能正确描述碳原子的位置分布。", "convertible": true, "correct_option": "FCC with tetrahedral interstices, where carbon atoms are located at the bonding points of the FCC lattice and four non-adjacent tetrahedral interstice positions", "choice_question": "What is the crystal structure of diamond?", "conversion_reason": "The answer is a standard and specific description of the crystal structure of diamond, which can be directly used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "FCC with tetrahedral interstices, where carbon atoms are located at the bonding points of the FCC lattice and four non-adjacent tetrahedral interstice positions", "B": "HCP with octahedral interstices, where carbon atoms occupy both the HCP lattice sites and octahedral voids", "C": "BCC with tetrahedral interstices, where carbon atoms are positioned at the BCC lattice points and tetrahedral voids", "D": "Simple cubic with body-centered carbon atoms, forming alternating layers of simple cubic and BCC arrangements" }, "correct_answer": "A", "explanation": "The correct answer is A because diamond has a face-centered cubic (FCC) structure with carbon atoms occupying both the FCC lattice points and half of the tetrahedral interstitial sites. Option B is incorrect because HCP with octahedral interstices describes the structure of materials like titanium carbide, not diamond. Option C is a trap for those who confuse BCC metals with diamond's FCC-based structure. Option D exploits the common misconception that diamond's layered appearance corresponds to alternating crystal structures, when in reality it's a single FCC derivative structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2396, "question": "Assuming the resistance (shear stress) that dislocation slip needs to overcome is 1.5×10^8 Pa for 30-51=Fe alloy, the shear modulus G for 3% Si-Fe alloy is 3.5×10^11 Pa, and the lattice constant is 0.28 nm. How thick is the low-dislocation-density layer near the surface of the 3% Si-Fe alloy? It is known that iron-silicon alloy has a body-centered cubic structure, and the Burgers vector length is 0.28√3/2 nm = 0.242 nm.", "answer": "Due to the effect of surface image force, dislocations near the surface are subjected to the image force F_im. When the image force is greater than or equal to the resistance to dislocation slip, the dislocation slips out of the surface, reducing the dislocation density near the surface. Taking a screw dislocation as an example, the image force F_im per unit length parallel to the surface is F_im = τ_in b = G b^2 / (4π d), where d is the distance of the dislocation from the surface. When F_im equals the resistance to dislocation slip, d represents the thickness of the low-dislocation-density layer near the surface. Therefore, d ≤ G b / (4π τ_⊥). The thickness of the low-dislocation-density layer for the iron-silicon alloy is d = (3.5×10^11 × 0.242×10^-9) / (4π × 1.5×10^8) m = 4.88×10^-8 m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解低位错密度层的厚度，解答过程中涉及多个物理量的代入和计算，最终得出具体的数值结果。 | 知识层次: 题目需要进行多步计算，涉及公式应用和概念关联（如表面镜像力、位错滑移阻力等），但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于高难度，需要综合运用多个材料科学概念（如位错理论、表面镜像力、剪切模量等），进行多步骤计算（包括单位转换、公式推导和数值计算），并理解复杂物理现象（位错在近表面的行为）。题目涉及的知识点深度和计算复杂度明显高于普通选择题要求。", "convertible": true, "correct_option": "4.88×10^-8 m", "choice_question": "Assuming the resistance (shear stress) that dislocation slip needs to overcome is 1.5×10^8 Pa for 30-51=Fe alloy, the shear modulus G for 3% Si-Fe alloy is 3.5×10^11 Pa, and the lattice constant is 0.28 nm. How thick is the low-dislocation-density layer near the surface of the 3% Si-Fe alloy? It is known that iron-silicon alloy has a body-centered cubic structure, and the Burgers vector length is 0.28√3/2 nm = 0.242 nm.", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.88×10^-8 m", "B": "2.44×10^-8 m", "C": "9.76×10^-8 m", "D": "1.22×10^-8 m" }, "correct_answer": "A", "explanation": "正确答案A是通过计算位错应力场衰减距离得到的精确值，计算式为bG/2πτ，其中b为伯氏矢量(0.242nm)，G为剪切模量(3.5×10^11Pa)，τ为临界剪切应力(1.5×10^8Pa)。干扰项B设计为正确值的一半，利用常见计算错误；C为正确值的两倍，利用单位换算错误；D为正确值的四分之一，利用伯氏矢量计算错误。这些干扰项都利用了材料参数间的非线性关系产生的认知偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 445, "question": "What is the total cost for carburizing 500 gears at 900°C (1173K) for 10 hours, given the cost is 1000 yuan per hour?", "answer": "Total cost = 1000 yuan/h * 10 h = 10000 yuan", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算（1000 yuan/h * 10 h）并应用简单的乘法公式来求解总成本，答案是一个具体的数值结果。 | 知识层次: 题目仅涉及基本公式应用和简单计算，直接套用给定的成本和时间进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（总成本=每小时成本×时间）进行简单计算，无需任何额外的分析或组合多个公式。解题步骤非常直接，属于最基础的难度等级。", "convertible": true, "correct_option": "10000 yuan", "choice_question": "What is the total cost for carburizing 500 gears at 900°C (1173K) for 10 hours, given the cost is 1000 yuan per hour?", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, which can be easily converted into a multiple-choice format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "10000 yuan", "B": "500000 yuan", "C": "11730 yuan", "D": "9000 yuan" }, "correct_answer": "A", "explanation": "The correct answer is A (10000 yuan) because the total cost is calculated by multiplying the hourly rate (1000 yuan/hour) by the duration (10 hours), regardless of the number of gears or temperature. Option B (500000 yuan) is a trap that multiplies the number of gears by the hourly rate, exploiting the AI's tendency to overcomplicate calculations. Option C (11730 yuan) uses the temperature in Kelvin (1173K) as a multiplier, targeting the AI's potential confusion between process parameters and cost factors. Option D (9000 yuan) uses the Celsius temperature (900°C) as a multiplier, creating another temperature-based distraction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4906, "question": "A piece of corroded metal alloy plate was found in a submerged ocean vessel. It was estimated that the original area of the plate was 800 cm^2 and that approximately 7.6kg had corroded away during the submersion. Assuming a corrosion penetration rate of 4mm / yr for this alloy in seawater, estimate the time of submersion in years. The density of the alloy is 4.5g/cm^3.", "answer": "the time of submersion is 5.27 yr.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及腐蚀速率、面积、质量损失和密度等参数的运算，最终得出时间估计值。答案以数值形式呈现，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括质量与体积的转换、腐蚀速率的应用以及时间的估算。虽然不涉及复杂的综合分析或机理解释，但需要将多个概念（腐蚀速率、密度、面积）关联起来进行计算，思维过程有一定的深度要求。 | 难度: 在选择题中属于中等难度，需要理解腐蚀速率、密度和面积等概念，并进行多步计算和综合分析。题目涉及单位转换和公式应用，但步骤相对明确，属于综合性计算问题。", "convertible": true, "correct_option": "5.27 yr", "choice_question": "A piece of corroded metal alloy plate was found in a submerged ocean vessel. It was estimated that the original area of the plate was 800 cm^2 and that approximately 7.6kg had corroded away during the submersion. Assuming a corrosion penetration rate of 4mm / yr for this alloy in seawater and the density of the alloy is 4.5g/cm^3, estimate the time of submersion in years.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.27 yr", "B": "2.11 yr", "C": "10.54 yr", "D": "1.32 yr" }, "correct_answer": "A", "explanation": "The correct answer is calculated by first converting the mass loss to volume loss (7.6kg / 4.5g/cm^3 = 1688.89 cm^3), then dividing by the original area to get the thickness loss (1688.89 cm^3 / 800 cm^2 = 2.11 cm), and finally dividing by the penetration rate (2.11 cm / 0.4 cm/yr = 5.27 yr). Option B is the thickness loss in cm, which is an intermediate step but not the final answer. Option C is double the correct answer, exploiting a common calculation error. Option D is one-fourth of the correct answer, playing on unit conversion errors between mm and cm.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4231, "question": "What is the composition, in atom percent, of an alloy that consists of 30 wt% Zn and 70 wt% Cu ?", "answer": "the composition of the alloy is 29.4 \\, \\text{at}% \\, \\mathrm{zn} and 70.6 \\, \\text{at}% \\, \\mathrm{cu}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（如原子百分比的计算）来得出合金的组成，答案也是具体的数值结果。 | 知识层次: 题目涉及基本的重量百分比到原子百分比的转换计算，需要应用简单的公式和进行数值计算，但不需要多步推理或综合分析。 | 难度: 在选择题中属于简单应用难度，需要应用基本公式（原子百分比计算公式）并进行简单计算，但不需要多个公式组合或复杂分析。", "convertible": true, "correct_option": "the composition of the alloy is 29.4 at% Zn and 70.6 at% Cu.", "choice_question": "What is the composition, in atom percent, of an alloy that consists of 30 wt% Zn and 70 wt% Cu?", "conversion_reason": "The answer is a specific and precise composition, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "29.4 at% Zn and 70.6 at% Cu", "B": "32.1 at% Zn and 67.9 at% Cu", "C": "27.8 at% Zn and 72.2 at% Cu", "D": "30.0 at% Zn and 70.0 at% Cu" }, "correct_answer": "A", "explanation": "The correct answer requires precise calculation using atomic weights (Zn=65.38, Cu=63.55). Option B reverses the weight percentage intuition, Option C introduces a common calculation error in atomic weight ratios, and Option D directly uses weight percentages as atomic percentages - a classic unit confusion trap. Advanced AIs may fail by either over-simplifying the conversion or misapplying the atomic weight ratios.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3923, "question": "Polyethylene may be fluorinated by inducing the random substitution of fluorine atoms for hydrogen. For this polymer, determine the concentration of F (in wt %) that must be added to completely fluorinate the material, i.e. to produce polytetrafluoroethylene (PTFE). Atomic weights for several elements are included in the following table: Carbon 12.01 g/mol, Chlorine 35.45 g/mol, Fluorine 19.00 g/mol, Hydrogen 1.008 g/mol, Oxygen 16.00 g/mol.", "answer": "the concentration of F required to completely fluorinate the material is 76.0 wt %.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定氟的浓度（wt %），需要用到原子重量和化学计量关系进行计算，最终给出一个具体的数值答案。 | 知识层次: 题目需要进行基本的化学计量计算，涉及原子质量和重量百分比的计算，属于直接套用公式和简单计算的范畴，不需要多步推理或综合分析。 | 难度: 在选择题中属于简单难度，题目要求应用基本公式进行简单计算，仅需理解聚乙烯完全氟化后生成聚四氟乙烯的化学结构变化，并套用原子量计算氟的质量百分比。解题步骤直接，无需复杂分析或多公式组合。", "convertible": true, "correct_option": "76.0 wt %", "choice_question": "Polyethylene may be fluorinated by inducing the random substitution of fluorine atoms for hydrogen. For this polymer, determine the concentration of F (in wt %) that must be added to completely fluorinate the material, i.e. to produce polytetrafluoroethylene (PTFE). Atomic weights for several elements are included in the following table: Carbon 12.01 g/mol, Chlorine 35.45 g/mol, Fluorine 19.00 g/mol, Hydrogen 1.008 g/mol, Oxygen 16.00 g/mol.", "conversion_reason": "The calculation question has a specific numerical answer (76.0 wt %), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "76.0 wt%", "B": "67.3 wt%", "C": "82.4 wt%", "D": "73.1 wt%" }, "correct_answer": "A", "explanation": "The correct answer is A (76.0 wt%) because the molecular formula of PTFE is (CF2)n. The weight percentage of fluorine is calculated as (2×19.00)/(12.01+2×19.00)×100% = 76.0%. Option B (67.3 wt%) is a common mistake from calculating based on polyethylene's original hydrogen content. Option C (82.4 wt%) incorrectly assumes complete substitution including carbon atoms. Option D (73.1 wt%) is a miscalculation that partially accounts for hydrogen replacement but uses wrong stoichiometry.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 689, "question": "A solid solution is an amorphous solid that has dissolved impurity components", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（A solid solution is an amorphous solid that has dissolved impurity components），并要求判断其正确性（答案给出×表示错误），符合判断题的特征。 | 知识层次: 题目考查对固溶体（solid solution）基本概念的记忆和理解，需要判断陈述是否正确，属于基础概念记忆的范畴。 | 难度: 该题目属于基础概念正误判断题，仅需记忆固体溶液的定义即可判断正误。在选择题型中，这类题目对知识点掌握深度要求最低，解题步骤最简单，属于最基础的难度等级。", "convertible": true, "correct_option": "×", "choice_question": "A solid solution is an amorphous solid that has dissolved impurity components", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All solid solutions exhibit complete miscibility across the entire composition range at equilibrium conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because while some solid solutions show complete miscibility (e.g., Cu-Ni system), many systems exhibit limited solubility or miscibility gaps. The use of 'all' makes this an absolute statement that doesn't account for phase diagrams showing partial solubility or immiscibility regions. A key subtlety is that equilibrium conditions don't guarantee complete miscibility - it depends on the specific thermodynamic properties of the components.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 868, "question": "Write the expression for the relationship between the diffusion coefficient and temperature, and indicate the physical meaning of each parameter.", "answer": "D=D0exp(-Q/RT), where D0 is the diffusion constant or frequency factor; Q is the diffusion activation energy (J/mol); T is the thermodynamic temperature of the system (K); R is the molar gas constant.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求写出扩散系数与温度关系的表达式，并解释各参数的物理意义。这需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目考查对扩散系数与温度关系的基本公式的记忆，以及各参数物理意义的理解，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求写出扩散系数与温度关系的表达式并解释各参数物理意义，但正确选项已经提供了完整的公式和参数解释。这需要考生对基础概念有一定的记忆和理解，但不需要进行复杂的分析或推导。题目主要考察对基本公式和参数定义的记忆，属于概念解释和描述的层次。", "convertible": true, "correct_option": "D=D0exp(-Q/RT), where D0 is the diffusion constant or frequency factor; Q is the diffusion activation energy (J/mol); T is the thermodynamic temperature of the system (K); R is the molar gas constant.", "choice_question": "Which of the following correctly represents the relationship between the diffusion coefficient and temperature, and explains the physical meaning of each parameter?", "conversion_reason": "The original short answer question asks for a standard expression and the explanation of its parameters, which can be converted into a multiple-choice question by providing the correct expression as one of the options and asking students to select the correct one.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "D=D0exp(-Q/RT), where D0 is the pre-exponential factor representing atomic vibration frequency; Q is the activation energy per mole; R is the universal gas constant; T is absolute temperature", "B": "D=D0exp(-Q/kT), where D0 is the diffusion constant; Q is the activation energy per atom; k is Boltzmann's constant; T is absolute temperature", "C": "D=D0Texp(-Q/RT), where D0 is the frequency factor; Q is the thermal activation energy; R is the material constant; T is process temperature", "D": "D=αTexp(-Q/RT), where α is the thermal diffusivity; Q is the energy barrier; R is the reaction constant; T is working temperature" }, "correct_answer": "A", "explanation": "Option A is correct as it properly represents the Arrhenius relationship for diffusion with all parameters correctly defined. Option B uses per-atom activation energy with Boltzmann's constant, which is a common confusion point between molar and atomic quantities. Option C incorrectly adds a linear temperature term before the exponential, a subtle trap for those recalling other material equations. Option D replaces D0 with thermal diffusivity α, exploiting confusion between different material properties while maintaining a plausible equation structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1346, "question": "How does chemical composition affect the diffusion coefficient?", "answer": "The addition of chemical elements hinders diffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释化学组成如何影响扩散系数，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释化学组成如何影响扩散系数，涉及多个概念的关联和综合分析，需要理解扩散机制与化学元素添加之间的关系，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解化学组成对扩散系数的影响这一概念，并能综合分析添加化学元素如何阻碍扩散过程。题目涉及中等应用层次的知识，要求考生将多个概念关联起来，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "The addition of chemical elements hinders diffusion.", "choice_question": "How does chemical composition affect the diffusion coefficient?", "conversion_reason": "The answer is a standard statement that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The addition of chemical elements hinders diffusion", "B": "Alloying elements always increase diffusion by creating more vacancies", "C": "Chemical composition has no effect on diffusion coefficient", "D": "Higher atomic number elements enhance diffusion by increasing atomic vibrations" }, "correct_answer": "A", "explanation": "Correct answer A is based on the well-established fact that solute atoms create strain fields that impede diffusion. Option B is a cognitive bias trap - while vacancies do facilitate diffusion, alloying elements typically bind to vacancies reducing their mobility. Option C exploits oversimplification bias by suggesting no relationship. Option D uses a plausible-sounding but incorrect mechanism (atomic vibrations are temperature-dependent, not composition-dependent for diffusion).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 134, "question": "Can glass be formed by rapid quenching at 1050°C?", "answer": "At this temperature, rapid quenching can form glass.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（玻璃是否可以通过在1050°C快速淬火形成），答案直接给出了对错判断。 | 知识层次: 题目考查玻璃形成的基本原理和温度条件的记忆，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅涉及玻璃形成的基本原理和温度条件的记忆性知识，不需要深入理解或复杂分析。正确选项直接陈述了基础概念，属于最基础层次的难度。", "convertible": true, "correct_option": "At this temperature, rapid quenching can form glass.", "choice_question": "Can glass be formed by rapid quenching at 1050°C?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials can be classified as glasses when cooled rapidly from the melt.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many amorphous materials can form glasses through rapid cooling, not all do. The classification as a glass requires the material to exhibit a glass transition temperature (Tg) upon heating. Some amorphous materials may crystallize instead of forming a glass, or may not show a clear Tg. This statement incorrectly uses the absolute term 'all' which is a precision trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2056, "question": "Analyze the basic conditions for the formation of single crystals", "answer": "The basic condition for forming a single crystal is to ensure that only one nucleus is generated (or only one nucleus can grow) during the crystallization of liquid metal, which then grows into a single crystal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求分析单晶形成的基本条件，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查单晶形成的基本条件，属于对基本原理的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆单晶形成的基本条件，即确保在液态金属结晶过程中只产生一个晶核（或只有一个晶核能够生长），从而形成单晶。这需要考生掌握相关的基础概念，但不需要进行复杂的分析或比较多个概念。因此，该题目在选择题型内属于中等难度。", "convertible": true, "correct_option": "The basic condition for forming a single crystal is to ensure that only one nucleus is generated (or only one nucleus can grow) during the crystallization of liquid metal, which then grows into a single crystal.", "choice_question": "Which of the following describes the basic condition for the formation of single crystals?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Maintaining a precisely controlled cooling rate that allows only one nucleation event to occur", "B": "Ensuring the liquid metal has extremely high purity (>99.999%) before solidification", "C": "Applying a strong magnetic field during solidification to align all crystal orientations", "D": "Using a seed crystal with identical lattice parameters to the target single crystal" }, "correct_answer": "A", "explanation": "The correct answer is A because single crystal formation fundamentally requires that only one nucleus forms and grows. Option B is a cognitive bias trap - while purity helps, it's not the fundamental condition. Option C exploits professional intuition about alignment but ignores that multiple nuclei could still form. Option D is a multi-level verification trap - seeding helps but isn't the basic condition, and lattice matching is overly specific.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3081, "question": "Tungsten-cobalt carbide is a composite material of (3) and (4)", "answer": "(3)WC; (4)Co", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的材料名称（WC和Co），属于需要简短文字回答的形式，而非选择、判断或计算 | 知识层次: 题目考查对钨钴碳化物复合材料基本组成的记忆，属于基础概念的记忆性知识，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，该题目仅要求记忆钨钴碳化物（Tungsten-cobalt carbide）的基本组成成分WC和Co，属于基础概念记忆的简单题目。不需要解释或分析，只需直接回忆相关知识即可作答。", "convertible": true, "correct_option": "WC and Co", "choice_question": "Tungsten-cobalt carbide is a composite material of:", "conversion_reason": "The answer is a standard terminology and can be converted into a multiple-choice question format by listing possible combinations of materials as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "WC and Co", "B": "W2C and Co", "C": "WC and Co3W", "D": "W2C and Co3W" }, "correct_answer": "A", "explanation": "The correct answer is A because tungsten-cobalt carbide is a well-known composite material consisting of tungsten carbide (WC) particles bonded with cobalt (Co) matrix. Option B uses W2C which is a metastable phase that doesn't form stable composites. Option C introduces Co3W which is an intermetallic compound that doesn't exist in standard WC-Co composites. Option D combines both incorrect phases (W2C and Co3W) creating a completely non-existent material system. The difficulty lies in the subtle differences between WC/W2C phases and the non-obvious fact that Co3W doesn't form in standard processing conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2104, "question": "Point out the errors in the following concepts and correct them: In the solid solution alloy, whether during equilibrium or non-equilibrium crystallization, the liquid phase composition at the liquid-solid interface changes along the average liquid composition line; the solid phase composition changes along the average solid composition line.", "answer": "The liquid phase composition at the liquid-solid interface changes along the liquidus line; the solid phase composition changes along the solidus line.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出概念中的错误并进行纠正，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目考查对固溶体合金结晶过程中液相和固相成分变化路径的基本概念的理解和记忆，属于基础概念的记忆性知识。 | 难度: 在选择题中属于中等难度，需要理解并区分平衡结晶和非平衡结晶过程中液相和固相成分的变化规律。虽然题目涉及的是基础概念记忆，但需要考生准确掌握液相线和固相线的定义及其在相图中的应用，并能识别和纠正错误描述。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "The liquid phase composition at the liquid-solid interface changes along the liquidus line; the solid phase composition changes along the solidus line.", "choice_question": "Which of the following correctly describes the changes in composition at the liquid-solid interface during crystallization in a solid solution alloy?", "conversion_reason": "The original short answer question asks for a correction of a specific concept, which can be rephrased into a multiple-choice format by presenting the correct statement as one of the options. The answer is a standard terminology or concept, making it suitable for conversion.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The liquid phase composition at the liquid-solid interface changes along the liquidus line; the solid phase composition changes along the solidus line", "B": "Both liquid and solid phase compositions at the interface follow the solidus line during non-equilibrium crystallization", "C": "The interface compositions remain constant and equal to the bulk alloy composition throughout the process", "D": "The liquid composition follows the solidus line while the solid composition follows the liquidus line" }, "correct_answer": "A", "explanation": "The correct answer follows the fundamental phase diagram rules where liquid composition follows the liquidus line and solid follows the solidus line during crystallization. Option B is designed to exploit confusion between equilibrium and non-equilibrium conditions. Option C creates a tempting simplification trap by suggesting constant compositions. Option D reverses the liquidus/solidus relationship, exploiting a common inversion error in phase diagram interpretation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3454, "question": "What are the types of heat-resistant steels?", "answer": "Commonly used heat-resistant steels are roughly divided into three categories according to their microstructure in the normalized state: pearlitic steel, martensitic steel, and austenitic steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和列举热阻钢的类型，答案提供了详细的分类和说明，属于需要文字解释和论述的简答题。 | 知识层次: 题目考查对热阻钢分类的基本概念记忆和理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆和识别热阻钢的基本分类，属于基础概念记忆层次。题目直接给出了正确选项，无需进行复杂的概念比较或分析，解题步骤简单，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "pearlitic steel, martensitic steel, and austenitic steel", "choice_question": "Which of the following are the types of heat-resistant steels?", "conversion_reason": "The answer is a standard list of terms, making it suitable for conversion to a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pearlitic, martensitic, and austenitic steels", "B": "Ferritic, bainitic, and duplex steels", "C": "Cementite, ledeburite, and sorbite steels", "D": "Hardenite, troostite, and widmanstatten steels" }, "correct_answer": "A", "explanation": "The correct answer is A because pearlitic, martensitic, and austenitic steels are the three main types of heat-resistant steels, each with distinct microstructures and temperature resistance properties. Option B uses real steel classifications but these are not primarily heat-resistant types. Option C uses names of microstructural constituents that are not standalone steel types. Option D contains fabricated terms that sound plausible but don't exist in metallurgy, exploiting the AI's tendency to recognize technical-sounding words.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 365, "question": "What are the types of deformation textures?", "answer": "Textures are divided into sheet textures and fiber textures.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释变形织构的类型，答案提供了文字解释和分类，符合简答题的特征 | 知识层次: 题目考查对变形织构类型的基本分类记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆和识别变形织构的基本分类（片状织构和纤维织构），属于最基础的定义简答类型。不需要进行概念解释或复杂体系阐述，解题步骤简单直接。", "convertible": true, "correct_option": "sheet textures and fiber textures", "choice_question": "What are the types of deformation textures?", "conversion_reason": "The answer is a standard terminology that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "sheet textures and fiber textures", "B": "elastic textures and plastic textures", "C": "isotropic textures and anisotropic textures", "D": "primary textures and secondary textures" }, "correct_answer": "A", "explanation": "The correct answer is A because deformation textures are specifically classified as sheet textures (developing under plane strain conditions) and fiber textures (developing under uniaxial deformation). Option B incorrectly uses elasticity/plasticity classifications which describe deformation mechanisms, not texture types. Option C describes material symmetry properties that can result from textures but are not texture classifications themselves. Option D falsely suggests a temporal hierarchy that doesn't exist in texture formation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 293, "question": "What are the characteristics of the microstructure and properties obtained by spinodal decomposition?", "answer": "The microstructure obtained by spinodal decomposition typically exhibits a quasi-periodic and interconnected composition modulation structure or a sponge-like organization, which is uniformly fine and can only be resolved under an electron microscope.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释spinodal分解获得的微观结构和性能特征，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目要求解释spinodal分解获得的微观结构和性能特征，涉及对分解机理的理解、微观结构的描述以及性能与结构关系的综合分析，需要较高的认知能力和深度理解。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解spinodal分解的基本概念，还需要掌握其微观结构特征（准周期、互连成分调制结构或海绵状组织）和性能特点（均匀细小、仅电子显微镜可分辨）。这需要综合运用材料科学原理进行复杂现象分析，并具备机理深度解释能力。选择题型中正确选项的识别需要考生对专业术语和微观组织特征有精确理解，远超简单记忆或基础概念识别的难度。", "convertible": true, "correct_option": "The microstructure obtained by spinodal decomposition typically exhibits a quasi-periodic and interconnected composition modulation structure or a sponge-like organization, which is uniformly fine and can only be resolved under an electron microscope.", "choice_question": "Which of the following describes the characteristics of the microstructure and properties obtained by spinodal decomposition?", "conversion_reason": "The answer is a standard description of the microstructure obtained by spinodal decomposition, which can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The microstructure obtained by spinodal decomposition typically exhibits a quasi-periodic and interconnected composition modulation structure or a sponge-like organization, which is uniformly fine and can only be resolved under an electron microscope.", "B": "Spinodal decomposition produces a lamellar microstructure with alternating layers of different compositions, similar to pearlite formation in steels.", "C": "The resulting microstructure shows randomly dispersed spherical precipitates with a Gaussian size distribution, analogous to classical nucleation and growth.", "D": "Spinodal decomposition creates a single-phase supersaturated solid solution with composition fluctuations invisible even at atomic resolution." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the unique interconnected and periodic nature of spinodal decomposition structures. Option B incorrectly applies lamellar morphology which is characteristic of eutectoid reactions. Option C describes classical nucleation behavior, exploiting the AI's potential confusion between different phase separation mechanisms. Option D reverses the key characteristic by suggesting invisibility, targeting the AI's possible overgeneralization of 'composition fluctuations'.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1637, "question": "Plastic deformation of metal polycrystals requires at least (14) independent slip systems to be activated", "answer": "(14) five", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个具体的数值（14）并补充说明（five），这需要简要的文字解释和论述，而不是从多个选项中选择或简单的对错判断。 | 知识层次: 题目考查对金属多晶体塑性变形所需独立滑移系统数量的基本概念记忆，属于定义性知识的直接回忆。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需回忆金属多晶体塑性变形所需的独立滑移系统数量。题目直接给出正确选项(14)，无需复杂推理或概念比较，属于最基本的知识点考察。", "convertible": true, "correct_option": "five", "choice_question": "Plastic deformation of metal polycrystals requires at least how many independent slip systems to be activated?", "conversion_reason": "The answer is a standard term (number) which can be presented as a choice in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "five", "B": "four", "C": "six", "D": "three" }, "correct_answer": "A", "explanation": "The correct answer is five because this is the minimum number of independent slip systems required to accommodate arbitrary plastic deformation in polycrystalline metals (von Mises criterion). Option B (four) is a cognitive bias trap - it's close to the correct number but insufficient for general deformation. Option C (six) exploits professional intuition by suggesting a higher number that actually corresponds to the total possible slip systems in FCC metals. Option D (three) is a multi-level verification trap - it matches the number needed for single crystal deformation but fails for polycrystals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 394, "question": "The brittle phase is dispersed in granular form in the matrix of another phase, which is a microstructure state that is more beneficial to the strength and toughness of the material.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（The brittle phase is dispersed...），并要求判断其正确性（答案：√），这是典型的判断题特征。 | 知识层次: 题目考查对材料微观结构状态及其对性能影响的基本概念记忆和理解，属于基础概念层次。 | 难度: 该题目属于基础概念记忆层次，仅需判断给定的陈述是否正确。题目描述的是材料科学中关于微观结构对强度和韧性影响的基本概念，正确选项明确，无需复杂分析或推理。在选择题型中，此类题目属于最简单的难度等级，仅需对基本定义或分类有记忆即可正确作答。", "convertible": true, "correct_option": "√", "choice_question": "The brittle phase is dispersed in granular form in the matrix of another phase, which is a microstructure state that is more beneficial to the strength and toughness of the material.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit higher fracture toughness than metals when the brittle phase is uniformly dispersed in a ductile matrix.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because while dispersion of brittle phases can improve toughness in some composites, the absolute claim that all ceramics surpass metals in toughness is incorrect. Many ceramics inherently have lower fracture toughness than metals. The improvement depends on specific phase distributions, interface properties, and loading conditions - making this an overgeneralization that ignores material-specific behaviors and the complex nature of toughening mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3922, "question": "Polyethylene may be fluorinated by inducing the random substitution of fluorine atoms for hydrogen. For this polymer, determine the concentration of F (in wt %) that must be added if this substitution occurs for 18.6 % of all of the original hydrogen atoms. Atomic weights for several elements are included in the following table: Carbon 12.01 g/mol, Chlorine 35.45 g/mol, Fluorine 19.00 g/mol, Hydrogen 1.008 g/mol, Oxygen 16.00 g/mol.", "answer": "the concentration of F that must be added is 18.0 wt %.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定氟的浓度（wt%）。解答过程涉及原子量的计算和百分比转换，最终给出具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括确定聚乙烯的重复单元、计算氢原子被氟原子替代的比例、计算氟原子的质量百分比等。这涉及到多个概念的关联和综合分析，而不仅仅是简单的公式应用或基础概念的记忆。 | 难度: 在选择题中属于中等偏上难度，需要理解聚合物氟化反应的概念，进行多步计算（包括原子质量计算、百分比转换等），并综合分析氢原子替换比例与最终氟含量的关系。虽然题目提供了原子质量数据，但解题过程涉及多个计算步骤和概念关联，比单纯记忆或简单计算题更复杂。", "convertible": true, "correct_option": "18.0 wt %", "choice_question": "Polyethylene may be fluorinated by inducing the random substitution of fluorine atoms for hydrogen. For this polymer, determine the concentration of F (in wt %) that must be added if this substitution occurs for 18.6 % of all of the original hydrogen atoms. Atomic weights for several elements are included in the following table: Carbon 12.01 g/mol, Chlorine 35.45 g/mol, Fluorine 19.00 g/mol, Hydrogen 1.008 g/mol, Oxygen 16.00 g/mol.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "18.0 wt%", "B": "23.7 wt%", "C": "15.2 wt%", "D": "32.4 wt%" }, "correct_answer": "A", "explanation": "正确答案18.0 wt%是通过精确计算聚乙烯分子中18.6%氢原子被氟取代后的质量百分比得出。干扰项B(23.7 wt%)利用了常见的摩尔分数与质量分数混淆陷阱，干扰项C(15.2 wt%)基于错误假设所有氢原子都被部分取代，干扰项D(32.4 wt%)则完全忽略了聚合物链结构的基本化学计量关系。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1654, "question": "Phase equilibrium", "answer": "The chemical potentials of each phase in the system are equal, and the chemical potentials of each component in each phase are equal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Phase equilibrium\"进行解释，答案提供了详细的文字论述，符合简答题的特征。 | 知识层次: 题目考查相平衡的基本概念，即化学势在相平衡中的条件，属于基本原理的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然涉及相平衡的基本概念，但正确选项需要理解化学势在相平衡中的具体表现（各相及各组分化学势相等），这超出了简单定义记忆的范畴。不过题目没有涉及复杂的概念体系或需要多步推理，因此属于概念解释和描述级别。", "convertible": true, "correct_option": "The chemical potentials of each phase in the system are equal, and the chemical potentials of each component in each phase are equal.", "choice_question": "Which of the following correctly describes phase equilibrium?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The chemical potentials of each phase in the system are equal, and the chemical potentials of each component in each phase are equal.", "B": "The Gibbs free energy of the system is minimized, and the temperature and pressure are uniform throughout all phases.", "C": "The composition of each phase remains constant over time, and the system has reached its lowest possible energy state.", "D": "The system exhibits no net mass transfer between phases, and the entropy production rate is zero." }, "correct_answer": "A", "explanation": "The correct answer is A because phase equilibrium requires the chemical potentials of each component to be equal across all phases, ensuring no driving force for phase transformation. Option B is incorrect because while Gibbs free energy minimization is a condition for equilibrium, uniform temperature and pressure alone do not guarantee phase equilibrium. Option C is a partial truth but fails to specify the critical chemical potential equality condition. Option D describes a consequence of equilibrium (no net mass transfer) but incorrectly includes entropy production rate, which is a condition for thermodynamic equilibrium, not specifically phase equilibrium.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3760, "question": "Calculate the height of the cylindrical riser required to prevent shrinkage in a 4 in. × 10 in. × 20 in. casting if the H / D of the riser is 1.5.", "answer": "the height of the riser h ≥ 10 in.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算圆柱形冒口的高度），并给出了具体的参数和条件（H/D比为1.5），答案也是一个具体的数值结果（h ≥ 10 in.），符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及圆柱形冒口高度与直径比（H/D）的应用，以及防止铸件缩孔的计算。虽然公式直接给出，但需要理解并正确应用这些概念和公式来解决问题，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解圆柱形冒口高度与直径比（H/D）的概念，并将该比例关系应用于具体尺寸计算。题目要求进行多步计算（根据H/D=1.5推导冒口直径与高度的关系），并需要综合分析铸造收缩预防的条件。虽然题目给出了具体尺寸简化了部分计算，但仍需正确应用工程原理并执行单位换算，这比单纯的概念选择题更具挑战性。", "convertible": true, "correct_option": "h ≥ 10 in.", "choice_question": "What is the height of the cylindrical riser required to prevent shrinkage in a 4 in. × 10 in. × 20 in. casting if the H / D of the riser is 1.5?", "conversion_reason": "The answer is a specific numerical condition (h ≥ 10 in.), which can be presented as a clear option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "h ≥ 10 in.", "B": "h ≥ 6.67 in.", "C": "h ≥ 15 in.", "D": "h ≥ 8.94 in." }, "correct_answer": "A", "explanation": "The correct answer is A because the riser height must be at least equal to the largest dimension of the casting (10 in.) to ensure proper solidification and prevent shrinkage. Option B is incorrect as it calculates based on the smallest dimension, exploiting the AI's tendency to average values. Option C is a trap for AI models that might overcompensate by using the product of dimensions. Option D is derived from the geometric mean, a common but incorrect approach in this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3389, "question": "What is the general process of spheroidizing annealing in the manufacturing process of round dies made from 9SiCr steel?", "answer": "Spheroidizing annealing process: heating temperature 790-810°C, isothermal temperature 700-720°C.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释球化退火的一般过程，答案提供了具体的温度参数，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查的是球化退火工艺的具体参数设置，需要理解工艺原理并关联具体材料（9SiCr钢）的应用，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及具体的工艺参数（加热温度和等温温度），需要考生对9SiCr钢的球化退火工艺有基本了解，并能将理论知识与实际工艺参数对应起来。虽然不需要复杂的计算，但需要对材料热处理工艺有综合理解才能正确选择答案。", "convertible": true, "correct_option": "Spheroidizing annealing process: heating temperature 790-810°C, isothermal temperature 700-720°C.", "choice_question": "What is the general process of spheroidizing annealing in the manufacturing process of round dies made from 9SiCr steel?", "conversion_reason": "The answer is a standard and specific description of the process, which can be directly used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Heating to 790-810°C followed by isothermal holding at 700-720°C", "B": "Heating to 850-870°C followed by rapid quenching in oil", "C": "Heating to 730-750°C with slow cooling at 20°C/hour", "D": "Cyclic heating between 650-750°C with air cooling" }, "correct_answer": "A", "explanation": "The correct answer is A because spheroidizing annealing specifically requires heating to just below the lower critical temperature (790-810°C for 9SiCr steel) followed by isothermal holding at 700-720°C to promote carbide spheroidization. Option B describes a quenching process which would produce martensite instead of spheroidized carbides. Option C uses incorrect temperature ranges and cooling rate for spheroidizing. Option D describes a stress relief process rather than spheroidizing. The interference options exploit common misconceptions about heat treatment processes and temperature ranges for tool steels.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1663, "question": "In a solid solution, when solute atoms and solvent atoms occupy fixed positions respectively, and the ratio of solute atoms to solvent atoms in each unit cell is constant, this ordered structure is called _ (6)—", "answer": "(6) superlattice", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（superlattice）来补全句子，属于需要简短文字回答的题目类型。 | 知识层次: 题目考查对有序结构（超晶格）这一基本概念的记忆和理解，属于定义性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即\"超晶格\"（superlattice）的定义。题目直接描述了有序结构的特征，并提供了明确的正确选项，无需复杂分析或推理。属于最基础的定义简答类型。", "convertible": true, "correct_option": "superlattice", "choice_question": "In a solid solution, when solute atoms and solvent atoms occupy fixed positions respectively, and the ratio of solute atoms to solvent atoms in each unit cell is constant, this ordered structure is called:", "conversion_reason": "The answer is a standard term (superlattice), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "superlattice", "B": "intermetallic compound", "C": "substitutional solid solution", "D": "interstitial solid solution" }, "correct_answer": "A", "explanation": "The correct answer is 'superlattice' because it specifically refers to an ordered arrangement where solute and solvent atoms occupy fixed positions with a constant ratio in each unit cell. 'Intermetallic compound' (B) is incorrect as it implies a new chemical compound rather than an ordered solid solution. 'Substitutional solid solution' (C) is a distractor that exploits the common confusion with disordered solid solutions where atoms randomly substitute for each other. 'Interstitial solid solution' (D) is a trap for those who misidentify the atomic positions as interstitial sites rather than substitutional ordering.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1144, "question": "How many slip systems can be formed in face-centered cubic metals?", "answer": "12", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答面心立方金属中可以形成的滑移系统数量，答案是一个具体的数字（12），但需要基于对滑移系统的理解和计算得出，属于需要简要回答的问题。 | 知识层次: 题目考查面心立方金属滑移系统数量的记忆性知识，属于基础概念的记忆和理解层面，不需要复杂的计算或分析过程。 | 难度: 在选择题型中，该题目仅需记忆面心立方金属的滑移系统数量（12个），属于基础概念记忆，无需复杂推理或分析。题目直接考察定义性知识，解题步骤简单，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "12", "choice_question": "How many slip systems can be formed in face-centered cubic metals?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项D", "B": "选项B", "C": "12", "D": "选项C" }, "correct_answer": "C", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 3108, "question": "Shape memory alloys utilize the characteristics of (1) and (2) of the material to achieve shape recovery.", "answer": "(1) superelasticity; (2) shape memory effect", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个特定的术语来完成句子，需要考生回忆和写出具体的专业术语，而不是从选项中选择或进行判断、计算。 | 知识层次: 题目考查形状记忆合金的基本特性（超弹性和形状记忆效应）的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中属于基础难度，仅需记忆形状记忆合金的两个基本特性（超弹性和形状记忆效应）即可正确作答，无需进行概念解释或复杂分析。", "convertible": true, "correct_option": "superelasticity and shape memory effect", "choice_question": "Shape memory alloys utilize the characteristics of which of the following to achieve shape recovery?", "conversion_reason": "The answer is a standard terminology that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Martensitic transformation and twinning deformation", "B": "Superelasticity and shape memory effect", "C": "Dislocation slip and grain boundary diffusion", "D": "Elastic modulus and Poisson's ratio" }, "correct_answer": "B", "explanation": "The correct answer is B because shape memory alloys rely on the superelasticity (pseudoelasticity) and shape memory effect, which are directly related to the reversible martensitic transformation. Option A is a cognitive bias trap - while martensitic transformation is correct, twinning deformation alone doesn't explain shape recovery. Option C exploits material science intuition by using real deformation mechanisms that don't contribute to shape memory. Option D uses fundamental material properties that are unrelated to the shape memory phenomenon.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1958, "question": "How does constitutional supercooling affect the growth morphology of solid solutions?", "answer": "In the absence of constitutional supercooling, the solid solution grows in a planar manner, forming equiaxed crystals; with a small degree of supercooling, cellular structures form; with a large degree of constitutional supercooling, dendritic crystals form.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释constitutional supercooling对固溶体生长形态的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及对constitutional supercooling如何影响固溶体生长形态的深入解释，需要理解并分析不同冷却条件下晶体生长的变化机制，属于对概念的深度理解和综合分析。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解\"成分过冷\"这一复杂概念，还需要掌握其对固溶体生长形貌的多层次影响机制（平面生长→胞状结构→枝晶形成）。正确选项涉及三个不同条件下的晶体生长形态变化，需要考生具备将热力学原理与晶体生长动力学相结合的分析能力。这种需要综合多个高阶概念并解释复杂现象的选择题，在材料科学选择题中属于最具挑战性的类型。", "convertible": true, "correct_option": "With a large degree of constitutional supercooling, dendritic crystals form.", "choice_question": "How does constitutional supercooling affect the growth morphology of solid solutions?", "conversion_reason": "The answer provided is a clear, specific description of the effects of constitutional supercooling on growth morphology, which can be converted into a multiple-choice format by presenting the different outcomes as options. The correct option is the part of the answer that describes the effect of a large degree of constitutional supercooling.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "With a large degree of constitutional supercooling, dendritic crystals form", "B": "Constitutional supercooling promotes planar growth front stability", "C": "It causes isotropic spherical crystal growth regardless of supercooling degree", "D": "Constitutional supercooling leads to amorphous phase formation" }, "correct_answer": "A", "explanation": "Correct answer A reflects the well-established relationship where constitutional supercooling destabilizes planar growth, leading to dendritic morphologies. Option B reverses the actual effect (cognitive bias trap). Option C violates fundamental crystal growth principles (intuition trap). Option D conflates kinetic effects with thermodynamic glass formation (concept confusion trap). Advanced AIs may select B due to overgeneralizing 'stability' concepts or D due to misapplying rapid solidification principles.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2873, "question": "Given that H70 brass [w(Zn)=30%] requires 1 hour to complete recrystallization at a constant temperature of 400°C, and 2 hours at 390°C, calculate the time required to complete recrystallization at a constant temperature of 420°C.", "answer": "Recrystallization is a thermally activated process, so the recrystallization rate; v_R = A exp(-Q/RT), and the recrystallization rate is inversely proportional to the time t required to achieve a certain volume fraction, i.e., v_R ∝ 1/t. 1/t = A' exp(-Q/RT) When recrystallization of the same degree occurs at two different constant temperatures, t1/t2 = e^(-Q/R (1/T2 - 1/T1)) Taking the natural logarithm on both sides: ln(t1/t2) = -Q/R (1/T2 - 1/T1). Similarly, ln(t1/t3) = -Q/R (1/T3 - 1/T1). Thus, (ln(t1/t2)) / (ln(t1/t3)) = (1/T2 - 1/T1) / (1/T3 - 1/T1) Substituting the corresponding data, we obtain t3 = 0.26 h.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解在420°C下完成再结晶所需的时间。解答过程中涉及到了热激活过程的公式推导、对数运算和数值代入计算，这些都是计算题的典型特征。 | 知识层次: 题目涉及多步计算和公式应用，需要理解再结晶过程的动力学关系，并运用对数变换和温度-时间关系进行综合分析。虽然不涉及复杂的机理分析或创新设计，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及热激活过程的速率方程、比例关系的推导、对数运算以及温度与时间的综合计算。解题步骤包括建立方程、代入数据、解方程等多个步骤，需要较强的综合分析能力和数学运算能力。虽然题目提供了部分解题思路，但整体计算过程较为复杂，属于综合性计算问题。", "convertible": true, "correct_option": "0.26 h", "choice_question": "Given that H70 brass [w(Zn)=30%] requires 1 hour to complete recrystallization at a constant temperature of 400°C, and 2 hours at 390°C, calculate the time required to complete recrystallization at a constant temperature of 420°C.", "conversion_reason": "The calculation yields a specific numerical answer (0.26 h), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.26 h", "B": "0.52 h", "C": "0.13 h", "D": "0.39 h" }, "correct_answer": "A", "explanation": "The correct answer is derived from the Arrhenius equation for recrystallization kinetics. Using the given data points (1h at 400°C and 2h at 390°C), we calculate the activation energy and then apply it to 420°C. Option B is derived by incorrectly assuming a linear relationship. Option C comes from miscalculating the temperature coefficient. Option D is a plausible-looking value that results from incorrect logarithmic calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1673, "question": "Cross-linked polymers cannot be reused and are called (20)__ plastics", "answer": "(20) thermosetting", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（thermosetting）来完成句子，这属于需要简短文字回答的类型，而不是从多个选项中选择或进行判断/计算 | 知识层次: 题目考查对交联聚合物分类的基础概念记忆，特别是热固性塑料的定义和特性，属于基础概念记忆性知识。 | 难度: 在选择题型中属于基础难度，仅需要记忆和识别\"thermosetting plastics\"这一基本定义即可作答，不涉及概念解释或复杂分析。题目直接考查学生对塑料分类的基础概念记忆，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "thermosetting", "choice_question": "Cross-linked polymers cannot be reused and are called:", "conversion_reason": "The answer is a standard term (thermosetting), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "thermosetting", "B": "thermoplastic", "C": "elastomeric", "D": "viscoelastic" }, "correct_answer": "A", "explanation": "The correct answer is A because cross-linked polymers form irreversible chemical bonds, making them thermosetting and non-reusable. Option B is incorrect as thermoplastics can be remelted and reused. Option C exploits the common confusion that elastomers are cross-linked but ignores that some can be thermoplastic. Option D uses a material property term that sounds plausible but is irrelevant to reusability.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1466, "question": "A pure edge dislocation loop can form in a crystal.", "answer": "True", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（True/False），符合判断题的特征 | 知识层次: 题目考查对位错类型（边缘位错环）这一基本概念的认知和理解，属于材料科学中晶体缺陷的基础知识范畴，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆边缘位错环的定义即可判断正确选项，无需深入理解或分析复杂概念。", "convertible": true, "correct_option": "True", "choice_question": "A pure edge dislocation loop can form in a crystal.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior under all loading conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain ceramics can exhibit ductile behavior under specific conditions (e.g., high temperatures, hydrostatic pressure, or nanocrystalline structures). The use of 'all' and 'under all loading conditions' makes this statement false due to these exceptions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1452, "question": "For a mixed dislocation line, what is the relationship between its Burgers vector and the dislocation line?", "answer": "Neither perpendicular nor parallel", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释混合位错线的Burgers矢量与位错线之间的关系，答案需要文字描述而非选择或判断。 | 知识层次: 题目考查对混合位错线的基本概念的理解，即其Burgers矢量与位错线方向的关系，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需考生记住混合位错线的柏氏矢量与位错线之间的关系是\"既不垂直也不平行\"这一基本定义即可作答。题目不涉及概念解释或复杂体系分析，属于最简单的记忆性知识考查。", "convertible": true, "correct_option": "Neither perpendicular nor parallel", "choice_question": "For a mixed dislocation line, what is the relationship between its Burgers vector and the dislocation line?", "conversion_reason": "The answer is a standard term that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Burgers vector is always perpendicular to the dislocation line", "B": "The Burgers vector is always parallel to the dislocation line", "C": "The Burgers vector can be either perpendicular or parallel depending on the slip system", "D": "Neither perpendicular nor parallel" }, "correct_answer": "D", "explanation": "The correct answer is D because a mixed dislocation has both edge and screw components, making the Burgers vector neither purely perpendicular nor parallel to the dislocation line. Option A exploits the common confusion with pure edge dislocations. Option B targets the misconception about screw dislocations. Option C creates a plausible-sounding but incorrect generalization about slip systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2011, "question": "The intermetallic compound AlNi has a CsCl-type structure with a lattice constant of $a=0.288\\\\mathrm{~nm}$. Calculate its density (the relative atomic mass of Ni is 58.71, and the relative atomic mass of Al is 26.98).", "answer": "Density $\\\\rho=5.97~\\\\mathrm{g}/\\\\mathrm{cm}^{3}$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解密度，答案是一个具体的数值结果。 | 知识层次: 题目要求计算密度，涉及基本公式应用（密度计算公式）和简单计算（代入已知数值进行计算），不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用密度计算公式，即$\\rho = \\frac{Z \\times M}{a^3 \\times N_A}$，其中$Z$为晶胞中的原子数（CsCl结构$Z=1$），$M$为摩尔质量，$a$为晶格常数，$N_A$为阿伏伽德罗常数。题目已提供所有必要参数，计算过程仅涉及单位换算和简单代数运算，无需多步骤推导或复杂概念理解，属于单一公式直接计算的等级1难度。", "convertible": true, "correct_option": "5.97 g/cm³", "choice_question": "The intermetallic compound AlNi has a CsCl-type structure with a lattice constant of $a=0.288\\mathrm{~nm}$. What is its density? (The relative atomic mass of Ni is 58.71, and the relative atomic mass of Al is 26.98.)", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.97 g/cm³", "B": "6.42 g/cm³", "C": "5.51 g/cm³", "D": "4.89 g/cm³" }, "correct_answer": "A", "explanation": "The correct density is calculated by considering the CsCl-type structure has 1 formula unit per unit cell. The volume is a³ = (0.288 nm)³ = 2.39×10⁻²³ cm³. The mass is (58.71 + 26.98)/6.022×10²³ = 1.42×10⁻²² g. Density = mass/volume = 5.97 g/cm³. Option B is designed to trap those who miscalculate the volume by using a² instead of a³. Option C exploits the common error of using 2 formula units per cell (like in FCC). Option D targets those who incorrectly convert nm to cm.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1743, "question": "A crystal structure with space group Fm3m belongs to the _ crystal family and crystal system. a. high b. intermediate c. low d. cubic e. hexagonal f. tetragonal g. orthorhombic", "answer": "a d", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且答案形式为选项字母组合 | 知识层次: 题目考查对晶体结构和空间群分类的基础概念记忆，属于对晶体家族和晶系的基本分类知识的直接回忆。 | 难度: 在选择题中属于中等难度，需要理解空间群Fm3m属于高对称性（high）和立方（cubic）晶系，并进行简单辨析。虽然涉及基础概念记忆，但需要将空间群与晶族和晶系对应起来，有一定的理解要求。", "convertible": true, "correct_option": "d", "choice_question": "A crystal structure with space group Fm3m belongs to the _ crystal family and crystal system.", "conversion_reason": "原题目已经是选择题格式，且答案明确为单一选项（d），可以转换为单选题。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy for vacancy diffusion decreases with increasing temperature due to thermal vibration assistance", "B": "The Arrhenius plot of vacancy diffusion always shows perfect linearity across all temperature ranges", "C": "The activation energy for interstitial diffusion is typically higher than for vacancy diffusion in the same crystal structure", "D": "The pre-exponential factor in diffusion equations is temperature-independent and solely determined by crystal structure" }, "correct_answer": "C", "explanation": "Correct answer C is correct because interstitial diffusion generally requires lower activation energy than vacancy diffusion as interstitials move through smaller, more direct paths. A is a strong cognitive bias trap - while thermal vibrations assist diffusion, the activation energy itself is a fundamental property that doesn't decrease with temperature. B exploits the common oversimplification of Arrhenius behavior, ignoring possible curvature at extreme temperatures. D targets the misconception that pre-exponential factors are purely structural, while they actually contain temperature-dependent terms like vibrational entropy.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1682, "question": "Based on the radius difference between Ca2+ and Mg2+ ions, calculate and determine whether CaO-MgO meets the size condition for forming a continuous solid solution. (The radii of Ca2+ and Mg2+ ions are known to be 0.1nm and 0.072nm, respectively)", "answer": "Size difference calculation: (0.1 - 0.072) / 0.1 = 28%. The size difference exceeds 15%, thus it does not meet the size condition for forming a continuous solid solution.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行具体的数值计算（半径差百分比计算），并根据计算结果得出结论（是否满足形成连续固溶体的尺寸条件）。答案展示了完整的计算过程和基于计算结果的判断，符合计算题的特征。 | 知识层次: 题目要求进行简单的数值计算和公式应用，即通过给定的离子半径计算尺寸差异百分比，并根据已知条件判断是否符合形成连续固溶体的尺寸条件。这一过程涉及基本的公式应用和直接套用，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用半径差公式进行计算，但步骤较为直接，仅涉及单一公式和简单百分比计算，无需多个概念或复杂分析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "Size difference exceeds 15%, thus it does not meet the size condition for forming a continuous solid solution.", "choice_question": "Based on the radius difference between Ca2+ (0.1nm) and Mg2+ (0.072nm) ions, does CaO-MgO meet the size condition for forming a continuous solid solution?", "conversion_reason": "The answer is a definitive conclusion based on a calculation, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because both are rock-salt structures with similar lattice parameters", "B": "No, the size difference exceeds 15% (calculated as 28%)", "C": "Yes, the charge similarity compensates for size difference", "D": "No, because CaO has higher ionic character than MgO" }, "correct_answer": "B", "explanation": "The correct answer is B because the size difference calculation (0.1-0.072)/0.072 = 28.9% clearly exceeds the 15% Hume-Rothery rule limit for solid solution formation. Option A exploits structural similarity bias, while Option C targets charge compensation misconception. Option D introduces an irrelevant ionic character factor to mislead.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4432, "question": "In terms of bonding, explain why silicate materials have relatively low densities.", "answer": "The silicate materials have relatively low densities because the atomic bonds are primarily covalent in nature, and, therefore, directional. This limits the packing efficiency of the atoms, and therefore, the magnitude of the density.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来说明硅酸盐材料密度较低的原因，答案提供了详细的解释，符合简答题的特征。 | 知识层次: 题目要求解释硅酸盐材料密度较低的原因，涉及对共价键方向性及其对原子堆积效率影响的理解和分析。这需要将键合类型与材料性质关联起来，属于中等应用层次的知识运用。 | 难度: 在选择题中属于中等难度，需要理解硅酸盐材料的键合性质（共价键的方向性）及其对原子堆积效率的影响，并将这些概念关联起来解释密度较低的原因。虽然不涉及多步计算，但需要进行概念关联和综合分析。", "convertible": true, "correct_option": "The atomic bonds are primarily covalent in nature, and, therefore, directional. This limits the packing efficiency of the atoms, and therefore, the magnitude of the density.", "choice_question": "Why do silicate materials have relatively low densities in terms of bonding?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The directional nature of covalent bonds limits atomic packing efficiency", "B": "Silicate materials contain large interstitial voids due to ionic repulsion", "C": "The low atomic number of silicon reduces electron density", "D": "Tetrahedral coordination creates excessive free volume in the crystal structure" }, "correct_answer": "A", "explanation": "Correct answer A addresses the fundamental covalent bonding nature in silicates. Distractors: B exploits ionic/covalent confusion (silicate bonds are primarily covalent), C uses a true fact (low Z) but misapplies it to density, and D sounds plausible but misrepresents tetrahedral coordination's actual efficient packing in silicates.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4075, "question": "Select T / F for the following statement regarding copper & copper alloys: Amongst metals and alloys copper is one of the best conductors of heat.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（Select T / F），答案形式为T（正确），符合判断题的特征。 | 知识层次: 题目考查对铜及其合金基本物理性质（导热性）的记忆和理解，属于基础概念记忆范畴 | 难度: 该题目属于基础概念正误判断，仅需记忆铜及其合金是优良的热导体这一基本事实即可作答，无需深入理解或分析多个概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "T", "choice_question": "Select T / F for the following statement regarding copper & copper alloys: Amongst metals and alloys copper is one of the best conductors of heat.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "Copper alloys always have lower electrical conductivity than pure copper, regardless of alloying elements or processing methods.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most alloying elements reduce copper's conductivity, certain specialized processing (like oxide dispersion strengthening) or minimal alloying can create copper alloys with comparable or situationally superior conductivity to pure copper under specific conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3307, "question": "What is the microstructural transformation of quenched steel during tempering at 250-400°C?", "answer": "Transformation of carbides", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释淬火钢在250-400°C回火时的微观结构转变，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对淬火钢在回火过程中微观结构转变的理解，需要将温度范围与具体的碳化物转变相关联，属于中等应用层次的知识。虽然不涉及复杂计算，但需要对材料科学中的相变和碳化物形成有较深入的理解，并能够综合分析不同温度下的微观结构变化。 | 难度: 在选择题中属于中等难度，需要理解淬火钢在回火过程中的微观结构转变，并关联碳化物的转变这一具体知识点。题目涉及中等应用层次的知识，要求考生能够综合分析回火温度范围与微观结构变化的关系，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Transformation of carbides", "choice_question": "What is the microstructural transformation of quenched steel during tempering at 250-400°C?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Formation of ε-carbide (Fe2-3C)", "B": "Decomposition of retained austenite", "C": "Recovery of dislocation density", "D": "Precipitation of cementite (Fe3C)" }, "correct_answer": "A", "explanation": "The correct answer is A because in the 250-400°C tempering range, the dominant transformation is the formation of ε-carbide from supersaturated martensite. Option B is incorrect because retained austenite decomposition primarily occurs above 200°C but is not the dominant transformation in this range. Option C is a cognitive bias trap as dislocation recovery occurs but is not the primary microstructural transformation. Option D is a professional intuition trap as cementite forms at higher temperatures (>400°C) but appears plausible due to its fundamental role in steel microstructure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4398, "question": "What is the chief difference between heat-treatable and non-heat-treatable alloys?", "answer": "The chief difference between heat-treatable and nonheat-treatable alloys is that heat-treatable alloys may be strengthened by a heat treatment wherein a precipitate phase is formed (precipitation hardening) or a martensitic transformation occurs. Nonheat-treatable alloys are not amenable to strengthening by such treatments.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述两种合金的主要区别，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对热可处理合金和非热可处理合金之间主要区别的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并区分两种合金的主要差异，包括热处理可强化合金的两种机制（沉淀硬化和马氏体转变）以及非热处理可强化合金的特性。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Heat-treatable alloys may be strengthened by a heat treatment wherein a precipitate phase is formed (precipitation hardening) or a martensitic transformation occurs, while nonheat-treatable alloys are not amenable to strengthening by such treatments.", "choice_question": "What is the chief difference between heat-treatable and non-heat-treatable alloys?", "conversion_reason": "The answer is a standard explanation of the difference between the two types of alloys, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": "N/A", "perplexity_level": "N/A", "perplexity_reason": "N/A", "missing_info": "N/A" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Heat-treatable alloys can undergo precipitation hardening or martensitic transformation, while non-heat-treatable alloys rely solely on cold working for strengthening", "B": "Non-heat-treatable alloys contain alloying elements that form stable compounds, preventing phase transformations upon heating", "C": "Heat-treatable alloys have higher melting points than non-heat-treatable alloys due to their complex microstructure", "D": "The difference lies in their crystal structure: heat-treatable alloys are primarily BCC while non-heat-treatable are FCC" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the fundamental difference in strengthening mechanisms. Option B creates confusion by mixing truth (stable compounds) with false causality (preventing transformations). Option C exploits the common misconception that heat treatment correlates with melting point. Option D uses a partially correct but ultimately irrelevant structural distinction, as both types can exist in either structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2117, "question": "Point out the errors in the following concepts and correct them: All equilibrium crystallization processes of carbon steel undergo eutectoid transformation but no eutectic transformation; conversely, cast iron only undergoes eutectic transformation but no eutectoid transformation.", "answer": "Conversely, cast iron undergoes both eutectic transformation and eutectoid transformation.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断陈述的对错并指出错误概念，答案是对错误陈述的纠正，符合判断题的特征 | 知识层次: 题目考查对碳钢和铸铁相变过程的基本概念记忆和理解，需要识别并纠正关于共晶和共析转变的错误陈述，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度等级。题目要求考生理解并区分碳钢和铸铁在平衡结晶过程中的相变行为（共析转变和共晶转变），并识别出原陈述中的错误。虽然涉及两个材料系统的相变概念，但只需要对基本定义和分类有清晰记忆即可做出正确判断，不需要复杂的分析或推理过程。", "convertible": true, "correct_option": "Conversely, cast iron undergoes both eutectic transformation and eutectoid transformation.", "choice_question": "Point out the errors in the following concepts and correct them: All equilibrium crystallization processes of carbon steel undergo eutectoid transformation but no eutectic transformation; conversely, cast iron only undergoes eutectic transformation but no eutectoid transformation.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In hypereutectoid steels, the proeutectoid phase that forms upon cooling from austenite is always cementite, regardless of cooling rate.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While cementite is the expected proeutectoid phase in hypereutectoid steels under equilibrium conditions, rapid cooling can lead to the formation of martensite or other non-equilibrium phases instead of cementite. The statement incorrectly uses 'always' which neglects non-equilibrium conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2141, "question": "In a ternary system during diffusion, can a three-phase coexistence region appear within the diffusion layer? Why?", "answer": "A three-phase coexistence region cannot exist within the diffusion layer of a ternary system. The reasons are as follows: If three-phase equilibrium coexistence occurs in a ternary system, the compositions of the three phases are fixed, and the chemical potentials of the same component in different phases are equal, resulting in a zero chemical potential gradient, making diffusion impossible.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对三元系统中扩散层内三相共存区域的存在性进行解释和论述，答案提供了详细的文字解释和理论依据，符合简答题的特征。 | 知识层次: 题目涉及三元系统中扩散层的多相平衡问题，需要理解相平衡条件、化学势梯度与扩散的关系，并进行逻辑推理和综合分析。这超出了简单记忆或基本应用的范围，属于对复杂现象的解释和分析。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "A three-phase coexistence region cannot exist within the diffusion layer of a ternary system.", "choice_question": "In a ternary system during diffusion, can a three-phase coexistence region appear within the diffusion layer?", "conversion_reason": "The answer is a clear and concise statement that can serve as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because the diffusion path must follow a continuous composition gradient", "B": "Yes, if the system has a miscibility gap in the phase diagram", "C": "Yes, when the interdiffusion coefficients satisfy D_AB = D_AC = D_BC", "D": "No, unless the system reaches local equilibrium at each point" }, "correct_answer": "A", "explanation": "The correct answer is A because in diffusion-controlled processes, the composition must vary continuously across the diffusion layer, preventing the formation of distinct phase boundaries required for three-phase coexistence. Option B is a cognitive bias trap, incorrectly applying equilibrium phase diagram concepts to non-equilibrium diffusion. Option C exploits professional intuition by suggesting a mathematical condition that seems plausible but is physically meaningless for phase coexistence. Option D is a multi-level verification trap, mixing correct equilibrium concepts with incorrect application to diffusion kinetics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2661, "question": "The crystal structure of Ni is face-centered cubic, and its atomic radius is r=0.1243nm. Calculate the lattice constant of Ni.", "answer": "a=4r/sqrt(2)=4×0.1243/sqrt(2)=0.3516(nm)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（使用原子半径和面心立方晶格常数公式）来求解镍的晶格常数，答案是一个具体的数值结果。 | 知识层次: 题目涉及基本的公式应用和简单计算，只需要套用已知的原子半径和面心立方晶格常数的关系公式进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目明确给出了面心立方晶体的晶格常数计算公式a=4r/sqrt(2)，只需要将给定的原子半径r=0.1243nm代入公式进行简单计算即可得到正确答案。不需要额外的概念理解或复杂的解题步骤，完全符合等级1\"单一公式直接计算\"的标准。", "convertible": true, "correct_option": "0.3516 nm", "choice_question": "The crystal structure of Ni is face-centered cubic, and its atomic radius is r=0.1243 nm. What is the lattice constant of Ni?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.3516 nm", "B": "0.2486 nm", "C": "0.4301 nm", "D": "0.1243 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.3516 nm) because in a face-centered cubic (FCC) structure, the relationship between the lattice constant (a) and atomic radius (r) is a = 4r/√2. For Ni with r=0.1243 nm, this gives a=0.3516 nm. Option B (0.2486 nm) is 2r, which is a common mistake from confusing FCC with simple cubic. Option C (0.4301 nm) incorrectly uses the relationship for body-centered cubic (BCC) structures (a=4r/√3). Option D (0.1243 nm) is just the atomic radius itself, exploiting unit confusion and surface-level thinking.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1552, "question": "3.Solid solution strengthening", "answer": "The presence of solute atoms in the solid solution causes lattice distortion of the solvent, thereby hindering dislocation motion and increasing its strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Solid solution strengthening\"进行解释说明，答案是通过文字论述来解释固溶强化的机制，符合简答题的特征。 | 知识层次: 题目考查固溶强化的基本概念和原理，属于对基础概念的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要理解固溶强化机制中溶质原子如何引起晶格畸变并阻碍位错运动。这比简单的定义记忆（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "The presence of solute atoms in the solid solution causes lattice distortion of the solvent, thereby hindering dislocation motion and increasing its strength.", "choice_question": "Which of the following best describes solid solution strengthening?", "conversion_reason": "The answer is a standard explanation of the concept, which can be presented as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The presence of solute atoms in the solid solution causes lattice distortion of the solvent, thereby hindering dislocation motion and increasing its strength.", "B": "The formation of secondary phases at grain boundaries restricts grain boundary sliding, leading to enhanced strength.", "C": "Solute atoms increase the elastic modulus of the matrix, making it more resistant to deformation.", "D": "Interstitial atoms create covalent bonds with the host lattice, significantly raising the melting point and strength." }, "correct_answer": "A", "explanation": "Option A is correct as it accurately describes the primary mechanism of solid solution strengthening through lattice distortion and dislocation pinning. Option B describes grain boundary strengthening, not solid solution strengthening. Option C is a cognitive bias trap, confusing elastic modulus effects with the actual strengthening mechanism. Option D is a professional intuition trap, incorrectly attributing strength increase to melting point elevation and covalent bonding rather than dislocation interactions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4163, "question": "Select the word combination that best completes this statement.\nWhen a semiconductor is exposed to a light source, its intrinsic carrier concentration will increase if the [a] of the light is [b] than band gap of the semiconductor.\n[a]: intensity, energy, wavelength, frequency, voltage, current, resistance\n[b]: greater, less", "answer": "([a] energy\n[b] greater", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的选项组合中选择最佳答案来完成句子，符合选择题的特征 | 知识层次: 题目考查半导体材料的基本概念，即光照射对半导体本征载流子浓度的影响，以及光能量与半导体带隙的关系。这属于基础概念的记忆和理解范畴，不需要复杂的应用或分析。 | 难度: 在选择题中属于中等偏下难度，需要理解半导体光激发的基本原理，并正确匹配能量与带隙的关系。虽然涉及基础概念记忆，但需要一定的概念理解和简单辨析能力，而非单纯的直接记忆。", "convertible": true, "correct_option": "energy greater", "choice_question": "When a semiconductor is exposed to a light source, its intrinsic carrier concentration will increase if the [a] of the light is [b] than band gap of the semiconductor.", "conversion_reason": "The original question is already in a multiple-choice format with specific options for [a] and [b]. It can be converted into a single-choice question by combining the correct options for [a] and [b].", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "energy greater", "B": "wavelength greater", "C": "intensity greater", "D": "frequency less" }, "correct_answer": "A", "explanation": "The correct answer is A because the intrinsic carrier concentration increases when the photon energy exceeds the band gap (E > Eg), enabling electron-hole pair generation. Option B exploits wavelength confusion (longer wavelength means lower energy). Option C targets the common misconception that light intensity alone determines carrier generation. Option D combines correct 'frequency' with wrong 'less' to create a plausible-sounding but incorrect pairing.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 249, "question": "What concentration of trivalent ions is required to ensure that the diffusion of Ca2+ in CaO remains non-intrinsic up to the melting point of CaO (2600°C)? The Schottky defect formation energy of CaO is known to be 6eV.", "answer": "The defect reaction for doping M3+ is as follows: M2O3 → 2M′′Ca + V′′Ca + 3OO. When CaO is at its melting point, the concentration of Schottky defects is: [V′′Ca] = exp(-ΔHf / 2RT) = exp(-6 × 1.6 × 10^-19 × 6.23 × 10^23 / (2 × 8.314 × 2873)) = 3.6 × 10^-6. Therefore, to ensure that the diffusion of Ca2+ in CaO remains non-intrinsic up to the melting point of CaO (2600°C), the concentration of M3+ must be [M3+] = [M′′Ca] = 2[V′′Ca] > [V′′Ca], i.e., [M3+] > 2 × 3.6 × 10^-6 = 7.2 × 10^-6.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，包括计算Schottky缺陷的浓度以及确定三价离子的浓度要求。答案中包含了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要理解Schottky缺陷的形成能、扩散机制以及掺杂浓度对扩散行为的影响，并进行相应的数值计算。虽然不涉及复杂的推理分析或创新应用，但需要综合运用多个知识点进行计算和判断。 | 难度: 在选择题中属于中等偏上难度，需要理解Schottky缺陷形成能的概念，掌握缺陷反应方程式的书写，并能进行多步计算（包括指数运算和单位转换）。此外，还需要综合分析掺杂浓度与缺陷浓度的关系，确保非本征扩散条件。虽然题目提供了正确选项，但解题过程涉及多个概念关联和计算步骤，对学生的知识掌握和计算能力要求较高。", "convertible": true, "correct_option": "7.2 × 10^-6", "choice_question": "What concentration of trivalent ions is required to ensure that the diffusion of Ca2+ in CaO remains non-intrinsic up to the melting point of CaO (2600°C)? The Schottky defect formation energy of CaO is known to be 6eV.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.2 × 10^-6", "B": "3.6 × 10^-6", "C": "1.4 × 10^-5", "D": "2.9 × 10^-7" }, "correct_answer": "A", "explanation": "The correct answer A (7.2 × 10^-6) is derived from the condition where the extrinsic defect concentration equals the intrinsic defect concentration at the melting point. Option B (3.6 × 10^-6) is half the correct value, exploiting the common calculation error of missing the 2:1 stoichiometry factor. Option C (1.4 × 10^-5) is designed based on incorrect Boltzmann factor calculation at 2600°C. Option D (2.9 × 10^-7) uses an order-of-magnitude error by misapplying the Schottky defect energy relationship.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1927, "question": "Please write the Burgers vector of the shortest unit dislocation in BCC crystals", "answer": "BCC: a/2<111>", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求写出BCC晶体中最短单位位错的Burgers矢量，答案需要特定的文字表述（a/2<111>），属于需要特定知识回答的简答题类型 | 知识层次: 题目考查BCC晶体中最短单位位错的Burgers向量的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆BCC晶体中最短单位位错的Burgers矢量表达式a/2<111>，属于基础概念记忆层次。题目不涉及概念解释或复杂体系阐述，仅需直接回忆定义即可作答，因此属于最简单的难度等级1。", "convertible": true, "correct_option": "a/2<111>", "choice_question": "What is the Burgers vector of the shortest unit dislocation in BCC crystals?", "conversion_reason": "The answer is a standard term in materials science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "a/2<111>", "B": "a<100>", "C": "a/2<110>", "D": "a<111>" }, "correct_answer": "A", "explanation": "The Burgers vector of the shortest unit dislocation in BCC crystals is a/2<111> because it represents the shortest perfect lattice translation vector in the BCC structure. Option B (a<100>) is a common misconception due to its simplicity in cubic systems but is not the shortest in BCC. Option C (a/2<110>) exploits the similarity to FCC crystal structures where this is the correct Burgers vector. Option D (a<111>) is a trap for those who recognize the <111> direction but forget to account for the minimum energy configuration with the a/2 magnitude.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3786, "question": "Suppose 1 at% of the following elements is added to copper (forming a separate alloy with each element) without exceeding the solubility limit. Which one would be expected to give the higher strength alloy? (a) Au (b) Mn (c) Sr (d) Si (e) Co", "answer": "(c)", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从多个选项（a-e）中选择一个预期能提供更高强度合金的元素，符合选择题的特征。 | 知识层次: 题目要求考生理解合金元素对铜强度的影响，并能够比较不同元素的强化效果。这需要考生掌握固溶强化的基本原理，并能够将不同元素的特性（如原子尺寸、电负性等）与强化效果联系起来。虽然不涉及复杂的计算或多步骤推理，但需要对概念进行综合应用和分析。 | 难度: 在选择题型中，该题目属于复杂分析过程的判断难度。需要考生：", "convertible": true, "correct_option": "(c) Sr", "choice_question": "Suppose 1 at% of the following elements is added to copper (forming a separate alloy with each element) without exceeding the solubility limit. Which one would be expected to give the higher strength alloy?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format without any modifications needed to the question text.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The alloy with Sr addition due to its larger atomic radius mismatch with Cu", "B": "The alloy with Mn addition because of its strong solid solution strengthening effect in Cu", "C": "The alloy with Si addition as it forms strong covalent bonds with Cu", "D": "The alloy with Co addition due to its similar crystal structure to Cu" }, "correct_answer": "A", "explanation": "The correct answer is A because Sr has the largest atomic radius mismatch with Cu among the options, creating significant lattice strain and thus stronger solid solution strengthening. Option B is a strong distractor as Mn is known for solid solution strengthening, but its atomic size difference with Cu is smaller than Sr. Option C exploits the misconception about covalent bonding in metallic systems. Option D uses the crystal structure similarity trap, which is irrelevant for solid solution strengthening effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3339, "question": "Determine the heat treatment conditions (temperature, time, cooling rate, etc.) for φ25 hot-rolled eutectoid steel during annealing.", "answer": "Annealing: hold at 760°C for 1h, furnace cooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求确定热处理条件（温度、时间、冷却速率等），需要文字解释和论述，答案给出了具体的处理条件和方式，属于简答题类型。 | 知识层次: 题目要求确定热轧共析钢的退火热处理条件，涉及温度、时间和冷却速率等参数的选择。这需要理解退火工艺的基本原理，并能根据具体材料（φ25热轧共析钢）进行参数选择和调整。虽然有一定的记忆成分，但更多是需要将理论知识应用到具体情境中，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。该题目要求考生掌握热轧共析钢的退火热处理条件，包括温度、时间和冷却速率等参数。虽然题目给出了正确选项，但考生需要理解退火工艺的基本原理，并能将理论知识与实际应用相结合。此外，还需要对共析钢的相变温度有所了解，才能正确判断760°C的保温温度是否合适。这些要求使得该题目在选择题型中处于中等难度水平。", "convertible": true, "correct_option": "Annealing: hold at 760°C for 1h, furnace cooling.", "choice_question": "What are the heat treatment conditions (temperature, time, cooling rate, etc.) for φ25 hot-rolled eutectoid steel during annealing?", "conversion_reason": "The answer is a standard and specific heat treatment condition, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hold at 760°C for 1h, furnace cooling", "B": "Hold at 720°C for 2h, air cooling", "C": "Hold at 800°C for 30min, water quenching", "D": "Hold at 680°C for 4h, controlled cooling at 50°C/h" }, "correct_answer": "A", "explanation": "The correct answer is A because eutectoid steel requires heating just above the A1 line (727°C) for full austenitization, with 760°C being optimal for annealing. Furnace cooling ensures full pearlite formation. Option B is incorrect because 720°C is below A1, and air cooling is too fast for annealing. Option C is wrong as 800°C is too high and water quenching produces martensite, not annealing. Option D uses subcritical temperature and incorrect cooling rate for full annealing.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1861, "question": "What is martensitic transformation?", "answer": "Martensitic transformation refers to a phase transformation that occurs at an extremely rapid speed through the shear of a discrete volume of a crystal under the action of external stress. Martensitic transformation is one of the basic forms of solid-state phase transformations.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对“马氏体转变”进行定义和解释，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即马氏体相变的定义和基本特征，属于基础概念记忆层次。 | 难度: 该题目属于选择题型中的概念解释和描述难度等级。题目要求考生理解并记忆马氏体相变的基本定义和特征，虽然涉及专业术语和基本原理，但不需要进行复杂的比较分析或多概念整合。在选择题型中，这属于中等偏下的难度，主要考察基础概念的记忆和理解能力。", "convertible": true, "correct_option": "Martensitic transformation refers to a phase transformation that occurs at an extremely rapid speed through the shear of a discrete volume of a crystal under the action of external stress. Martensitic transformation is one of the basic forms of solid-state phase transformations.", "choice_question": "Which of the following best describes martensitic transformation?", "conversion_reason": "The answer is a standard definition of a scientific concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A diffusionless phase transformation occurring through coordinated atomic shear, resulting in a characteristic lenticular microstructure", "B": "A thermally activated diffusion-controlled transformation that follows classical nucleation and growth kinetics", "C": "A reversible displacive transformation that always results in perfect crystallographic registry between parent and product phases", "D": "An interface-controlled transformation where the rate is determined by atomic mobility across the phase boundary" }, "correct_answer": "A", "explanation": "The correct answer is A because martensitic transformation is indeed diffusionless and occurs through shear mechanisms, forming characteristic lenticular microstructures. Option B is incorrect as it describes diffusional transformations like pearlite formation. Option C is wrong because while martensitic transformations are displacive, they are not always perfectly coherent and are often irreversible in ferrous systems. Option D describes transformations like massive transformations, not martensitic. The traps exploit common misconceptions: B uses diffusion-control (a cognitive bias), C suggests perfect reversibility (a professional intuition trap), and D mimics interface control (a multi-level verification trap).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2039, "question": "If the maximum undercooling during the solidification of pure nickel is 0.18 times its melting point $(t_{\\\\mathrm{m}}=1453^{\\\\circ}\\\\mathrm{C})$, calculate the driving force for solidification. $(\\\\Delta H=-18075.\\\\mathrm{J/mol})$", "answer": "The driving force for solidification $\\\\Delta G=-3~253.5~\\\\mathrm{J/mol},$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，以求解凝固驱动力，答案给出了具体的计算结果。 | 知识层次: 题目要求应用基本公式进行简单计算，涉及驱动力的计算和基本热力学概念的直接应用，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解最大过冷度和凝固驱动力之间的关系，但解题步骤相对直接，仅需套用给定的公式进行简单计算即可得出答案。不需要复杂的推导或多步骤计算，因此难度等级为2。", "convertible": true, "correct_option": "-3 253.5 J/mol", "choice_question": "If the maximum undercooling during the solidification of pure nickel is 0.18 times its melting point (t_m=1453°C), what is the driving force for solidification? (ΔH=-18075 J/mol)", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-3,253.5 J/mol", "B": "-2,902.8 J/mol", "C": "-3,615.0 J/mol", "D": "-4,000.0 J/mol" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula ΔG = ΔH × ΔT/T_m, where ΔT is the undercooling (0.18 × 1453°C = 261.54°C). Option B is incorrect because it uses ΔT in Kelvin without converting from Celsius, creating a temperature unit trap. Option C is a cognitive bias trap that incorrectly uses the full melting temperature instead of undercooling. Option D is a professional intuition trap that overestimates the driving force by assuming a linear relationship with undercooling.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3114, "question": "What characteristics do high-elastic alloys have?", "answer": "These alloys require a high elastic limit σe and a low elastic modulus E, meaning a high σe/E ratio, which minimizes the elastic after-effect of components and ensures stable operation. Additionally, they must possess high fatigue strength and good workability.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释高弹性合金的特性，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查高弹性合金的基本特性，包括弹性极限、弹性模量、疲劳强度和加工性能等基础概念的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个概念（弹性极限、弹性模量、疲劳强度、加工性等），但正确选项已经将这些概念整合成一条清晰的逻辑链，考生只需理解并匹配这些基本概念即可选出正确答案。不需要进行复杂的比较分析或推导，但需要掌握相关术语的定义和基本关系。", "convertible": true, "correct_option": "These alloys require a high elastic limit σe and a low elastic modulus E, meaning a high σe/E ratio, which minimizes the elastic after-effect of components and ensures stable operation. Additionally, they must possess high fatigue strength and good workability.", "choice_question": "Which of the following characteristics do high-elastic alloys have?", "conversion_reason": "The answer is a standard description of the characteristics of high-elastic alloys, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High σe/E ratio and excellent fatigue resistance", "B": "Low thermal expansion coefficient and high hardness", "C": "High elastic modulus and superior creep resistance", "D": "Low yield strength and high fracture toughness" }, "correct_answer": "A", "explanation": "Correct answer A captures the essential characteristics: high elastic limit to modulus ratio (σe/E) minimizes elastic after-effect, and fatigue resistance is critical for cyclic loading applications. Option B incorrectly focuses on thermal properties irrelevant to elasticity. Option C reverses the required modulus relationship (needs low E, not high). Option D contradicts the fundamental requirement for high yield strength in elastic alloys.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 222, "question": "What is the practical significance of Gibbs phase rule?", "answer": "Applying the phase rule can conveniently determine the degrees of freedom of an equilibrium system.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释Gibbs相律的实际意义，答案需要文字论述而非选择、判断或计算 | 知识层次: 题目考查对Gibbs相规则的基本概念和实用意义的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于选择题型中的概念解释和描述难度等级。题目要求考生理解Gibbs相律的实际意义，并能够识别其应用场景（确定平衡系统的自由度）。虽然涉及基础概念记忆，但需要一定的理解能力来将原理与实际应用联系起来，比单纯记忆定义（等级1）稍复杂，但不需要复杂概念体系阐述（等级3）。", "convertible": true, "correct_option": "Applying the phase rule can conveniently determine the degrees of freedom of an equilibrium system.", "choice_question": "What is the practical significance of Gibbs phase rule?", "conversion_reason": "The answer is a standard explanation of the practical significance of Gibbs phase rule, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Applying the phase rule can conveniently determine the degrees of freedom of an equilibrium system", "B": "It provides a direct method to calculate the exact composition of each phase in a system", "C": "The rule allows precise prediction of phase transformation kinetics under non-equilibrium conditions", "D": "Gibbs phase rule determines the maximum number of stable phases that can coexist in any material system" }, "correct_answer": "A", "explanation": "The correct answer is A because Gibbs phase rule fundamentally relates the number of components, phases, and degrees of freedom in an equilibrium system. Option B is incorrect because the phase rule doesn't provide compositional information - it's a common misconception that phase rule gives exact compositions. Option C is a kinetics trap - the phase rule only applies to equilibrium conditions, not transformation rates. Option D is a subtle exaggeration - while the rule constrains phase coexistence, it doesn't determine the absolute maximum number possible in all cases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4896, "question": "Briefly describe laminar composites.", "answer": "Laminar composites are a series of sheets or panels, each of which has a preferred high-strength direction. These sheets are stacked and then cemented together such that the orientation of the high-strength direction varies from layer to layer.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述层状复合材料，答案以文字解释和论述的形式给出，没有涉及选择、判断或计算。 | 知识层次: 题目考查对层状复合材料基本概念的记忆和理解，包括其结构和组成方式，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求的是基础概念记忆，但正确选项需要对层状复合材料的结构和组成有较为清晰的理解和描述，而不仅仅是简单的定义复述。这需要考生能够解释和描述概念，而不仅仅是识别或回忆基本定义。因此，该题目在选择题型内属于等级2的难度。", "convertible": true, "correct_option": "Laminar composites are a series of sheets or panels, each of which has a preferred high-strength direction. These sheets are stacked and then cemented together such that the orientation of the high-strength direction varies from layer to layer.", "choice_question": "Which of the following best describes laminar composites?", "conversion_reason": "The answer is a standard definition of laminar composites, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Laminar composites are a series of sheets or panels, each with a preferred high-strength direction, stacked and cemented together with varying orientations of the high-strength direction between layers.", "B": "Laminar composites consist of parallel fibers embedded in a matrix material, where the fiber orientation is uniform throughout the entire structure.", "C": "Laminar composites are isotropic materials formed by alternating layers of ceramic and metallic phases to achieve balanced mechanical properties.", "D": "Laminar composites refer to nanostructured materials where individual atomic layers are deposited to create alternating regions of different crystallographic orientations." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the key characteristics of laminar composites: layered structure with controlled orientation variation. Option B incorrectly describes unidirectional fiber composites. Option C falsely suggests isotropy and ceramic-metal alternation, which are not defining features. Option D inaccurately associates laminar composites with atomic-scale deposition techniques, confusing macroscale laminates with nanoscale superlattices.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4113, "question": "Carbon fiber-reinforced composites have high service temperatures (>200 degrees C)?", "answer": "Carbon fiber-reinforced composites have high service temperatures (>200 degrees C).", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（对错），答案直接给出了陈述句本身，符合判断题的特征。 | 知识层次: 题目考查对碳纤维增强复合材料基本性能的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念记忆层次，仅需判断碳纤维增强复合材料是否具有高温使用性能（>200°C）这一基本事实。在选择题型中，此类正误判断题是最简单的类型，无需理解或分析复杂概念，仅需回忆相关定义即可作答。", "convertible": true, "correct_option": "Carbon fiber-reinforced composites have high service temperatures (>200 degrees C).", "choice_question": "Carbon fiber-reinforced composites have high service temperatures (>200 degrees C)?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All carbon fiber-reinforced polymer composites can maintain their mechanical properties indefinitely at temperatures above 200°C.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While some high-performance carbon fiber composites can withstand temperatures above 200°C, the statement is false because: 1) 'All' is an absolute term that doesn't account for variations in matrix materials (epoxy resins typically degrade at 150-200°C), 2) 'indefinitely' ignores time-dependent property degradation, and 3) mechanical properties are matrix-dependent - while carbon fibers themselves can withstand high temperatures, most polymer matrices cannot. The correct assessment requires considering the specific composite system and exposure duration.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2946, "question": "When most of the latent heat of crystallization can be dissipated through the liquid phase during ingot solidification, the main solid microstructure is (A) dendritic crystal (B) columnar crystal (C) spherulite", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的三个选项（A、B、C）中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查对凝固过程中微观结构形成的基本概念的理解和记忆，属于基础概念记忆范畴。 | 难度: 该题目属于基础概念记忆层次，考察学生对凝固过程中微观组织形成的理解。虽然需要知道不同晶体结构（枝晶、柱状晶、球晶）的形成条件，但题目已经明确给出了关键条件（潜热通过液相散失），只需将这一条件与枝晶形成对应起来即可。相比纯粹的定义记忆题（等级1），此题需要一定的概念理解和简单辨析能力，但不需要复杂的分析或深度推理（等级3）。", "convertible": true, "correct_option": "A", "choice_question": "When most of the latent heat of crystallization can be dissipated through the liquid phase during ingot solidification, the main solid microstructure is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dendritic growth with secondary arm spacing <100μm", "B": "Equiaxed grains with random crystallographic orientation", "C": "Directionally solidified columnar structure", "D": "Single crystal with <5° misorientation" }, "correct_answer": "A", "explanation": "When latent heat is primarily dissipated through the liquid phase, it creates constitutional supercooling conditions that promote dendritic growth (A). The fine secondary arm spacing indicates rapid heat extraction. Option B is incorrect because equiaxed grains form when heat flows through the solid. Option C is a trap for those confusing heat flow directions - columnar structures require solid-phase heat dissipation. Option D exploits the common misconception that single crystals can form under these conditions, while in reality they require extremely controlled solidification.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 923, "question": "Briefly describe the types of defects in metal crystals", "answer": "According to size, they can be divided into: point defects, such as solute, impurity atoms, vacancies; line defects, such as dislocations; planar defects, such as various grain boundaries, phase boundaries, surfaces, etc.; volume defects, such as pores, bubbles, etc. Volume defects are absolutely harmful to material properties.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述金属晶体中的缺陷类型，答案提供了详细的文字解释和分类论述，符合简答题的特征。 | 知识层次: 题目考查金属晶体缺陷的基本分类和定义，属于基础概念的记忆和理解层面，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目要求考生对金属晶体缺陷的分类进行描述，涉及点缺陷、线缺陷、面缺陷和体缺陷的基本概念。虽然需要记忆多个分类和例子，但题目仅要求简要描述，不涉及复杂的概念体系或深入分析，属于概念解释和描述的难度水平。", "convertible": true, "correct_option": "According to size, they can be divided into: point defects, such as solute, impurity atoms, vacancies; line defects, such as dislocations; planar defects, such as various grain boundaries, phase boundaries, surfaces, etc.; volume defects, such as pores, bubbles, etc. Volume defects are absolutely harmful to material properties.", "choice_question": "Which of the following correctly describes the types of defects in metal crystals?", "conversion_reason": "The answer is a standard description of metal crystal defects, which can be converted into a multiple-choice question format by presenting it as the correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Point defects include vacancies and interstitials; dislocations are line defects; grain boundaries are planar defects; voids are volume defects", "B": "Schottky defects are line defects; Frenkel defects are volume defects; twin boundaries are point defects; stacking faults are planar defects", "C": "Vacancies and interstitials are volume defects; dislocations are point defects; grain boundaries are line defects; voids are planar defects", "D": "All crystal defects can be classified as either point defects or planar defects, with no distinction between line and volume defects" }, "correct_answer": "A", "explanation": "Option A correctly categorizes defects by dimensionality: point (0D), line (1D), planar (2D), and volume (3D). Option B strategically misclassifies well-known defect types to exploit familiarity bias. Option C reverses the dimensional classifications to create counterintuitive errors. Option D oversimplifies the classification system, appealing to reductionist thinking. Advanced AIs may stumble by over-analyzing the dimensional relationships or misapplying defect terminology across different material systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 364, "question": "Why do point defects (such as interstitial atoms or substitutional atoms) and line defects (such as dislocations) interact?", "answer": "Point defects cause distortion, increasing local energy and creating an elastic strain field nearby; dislocations also exhibit this behavior, but the stress field state around dislocations varies at different positions, with some being compressive stress and others tensile stress. Point defects will aggregate onto dislocations to reduce strain energy, thereby lowering the system's energy. Dislocations that adsorb solute atoms represent a stable configuration.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释点缺陷和线缺陷之间的相互作用机制，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释点缺陷和线缺陷之间的相互作用机制，涉及弹性应变场、应力状态变化以及系统能量降低的原理。这需要综合运用多个概念（点缺陷、位错、应变场、能量状态）进行推理分析，并解释其背后的物理机制，属于较高层次的认知要求。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求深入理解点缺陷和线缺陷的相互作用机理，包括弹性应变场、应力状态变化以及系统能量降低的复杂过程。正确选项不仅需要综合运用多个核心概念（如点缺陷的畸变效应、位错的应力场特性），还需要进行机理层面的推理分析（如缺陷聚集降低应变能的原理）。这种深度解释和复杂现象分析的要求远超一般选择题的知识点记忆或简单应用，完全符合等级5\"复杂现象全面分析\"的标准。", "convertible": true, "correct_option": "Point defects cause distortion, increasing local energy and creating an elastic strain field nearby; dislocations also exhibit this behavior, but the stress field state around dislocations varies at different positions, with some being compressive stress and others tensile stress. Point defects will aggregate onto dislocations to reduce strain energy, thereby lowering the system's energy. Dislocations that adsorb solute atoms represent a stable configuration.", "choice_question": "Why do point defects (such as interstitial atoms or substitutional atoms) and line defects (such as dislocations) interact?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be kept as is, and the answer can be one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Point defects aggregate at dislocations to minimize the system's strain energy by reducing the elastic strain fields of both defects", "B": "Dislocations act as fast diffusion paths for point defects, causing them to accumulate at dislocation cores", "C": "The stress fields of dislocations create preferential sites for point defects to occupy based on atomic size mismatch", "D": "Point defects pin dislocations through electrostatic interactions between charged defect centers" }, "correct_answer": "A", "explanation": "Correct answer A captures the fundamental energy minimization principle through strain field interaction. B exploits diffusion path intuition but incorrectly attributes the primary interaction mechanism. C uses size mismatch reasoning which is partially correct but secondary to strain energy reduction. D introduces electrostatic trapping which is irrelevant for neutral defects in metals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4015, "question": "Is solid aluminum featuring dissolved silicon a two-phase material system?", "answer": "No, it is a solid solution since silicon is implied to substitute for aluminum. Solutions are single-phase by definition.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断一个陈述的对错（\"Is solid aluminum featuring dissolved silicon a two-phase material system?\"），答案直接给出了对错判断（\"No\"）并解释了原因。这符合判断题的特征。 | 知识层次: 题目考查对固溶体和两相系统基本定义的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基本概念正误判断，仅需记忆固体溶液的定义和单相系统的概念即可做出正确选择，无需深入理解或分析复杂概念。", "convertible": true, "correct_option": "No, it is a solid solution since silicon is implied to substitute for aluminum. Solutions are single-phase by definition.", "choice_question": "Is solid aluminum featuring dissolved silicon a two-phase material system?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All solid solutions exhibit complete solubility of solute atoms in the solvent lattice at all concentrations.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because solid solutions have solubility limits that vary with temperature and atomic size factors. Complete solubility only occurs in rare cases when the Hume-Rothery rules are fully satisfied (similar atomic radii, same crystal structure, similar electronegativity, and same valence). Most solid solutions have limited solubility ranges.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1806, "question": "In the orthorhombic system, the possible types of space lattices are a.P, I, C b.P, 1, F c.P, C, F d.P, F, 1, C", "answer": "d", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且提供了明确的选项和答案 | 知识层次: 题目考查对正交晶系可能的空间格子类型的基本概念记忆，属于定义和分类的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆层次，要求考生记住正交晶系中可能的空间格子类型。虽然需要记忆多个选项，但只需识别正确组合，无需复杂分析或深度理解。相对于等级1的直接记忆题目，该题需要简单辨析不同选项的差异，因此属于等级2难度。", "convertible": true, "correct_option": "d", "choice_question": "In the orthorhombic system, the possible types of space lattices are:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "P, I, C", "B": "P, 1, F", "C": "P, C, F", "D": "P, F, I, C" }, "correct_answer": "D", "explanation": "The orthorhombic system has four Bravais lattices: primitive (P), base-centered (C), face-centered (F), and body-centered (I). Option D correctly lists all four. Option A incorrectly excludes F, Option B uses '1' which is invalid notation and excludes C, and Option C incorrectly excludes I. The interference strategies include: 1) Using '1' to mimic common notation errors (cognitive bias), 2) Omitting one correct lattice type to exploit pattern recognition (intuition trap), and 3) Presenting plausible but incomplete combinations (multilevel verification trap).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1061, "question": "Write all the crystal planes included in the {110} crystal plane family in the cubic crystal system", "answer": "(110)(101)(011)(110)(101)(011), totaling 6.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举立方晶系中{110}晶面族包含的所有晶面，答案需要具体列出所有符合条件的晶面，属于需要具体回答的简答题类型。 | 知识层次: 题目考查立方晶系中{110}晶面族包含的所有晶面，属于基础概念的记忆和理解，不需要复杂的计算或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆（{110}晶面族的组成），但需要学生准确回忆立方晶系中所有等效晶面的指数表示，并正确识别正负指数的不同组合。这比单纯记忆单个定义（等级1）要求更高，但不需要复杂的概念体系阐述（等级3）。解题步骤主要是回忆和应用对称性规则，属于概念解释和描述层面的要求。", "convertible": true, "correct_option": "(110)(101)(011)(110)(101)(011), totaling 6", "choice_question": "Which of the following lists all the crystal planes included in the {110} crystal plane family in the cubic crystal system?", "conversion_reason": "The answer is a standard and specific list of crystal planes, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(110)(101)(011)(110)(101)(011)", "B": "(110)(101)(011)(110)(101)(011)(111)(111)", "C": "(110)(101)(011)", "D": "(110)(101)(011)(110)(101)(011)(100)(010)(001)" }, "correct_answer": "A", "explanation": "The correct answer A lists all 6 equivalent planes in the {110} family for cubic crystals. Option B incorrectly includes (111) planes which belong to a different family. Option C misses the negative-index planes, a common oversight when considering symmetry. Option D adds (100) family planes, exploiting the tendency to overgeneralize cubic symmetry relationships.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4824, "question": "Which of the following polymers would be suitable for the fabrication of cups to contain hot coffee: polyethylene, polypropylene, poly(vinyl chloride), PET polyester, and polycarbonate. Why?", "answer": "This question asks us to name, which, of five polymers, would be suitable for the fabrication of cups to contain hot coffee. At its glass transition temperature, an amorphous polymer begins to soften. The maximum temperature of hot coffee is probably slightly below 100^{\\circ} C\\left(212^{\\circ} F\\right). Of the polymers listed, only polystyrene and polycarbonate have glass transition temperatures of 100^{\\circ} C or above, and would be suitable for this application.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么某些聚合物适合制作热咖啡杯，需要文字解释和论述，而不是简单的选择或判断。答案提供了详细的解释和理由，符合简答题的特征。 | 知识层次: 题目要求考生从多个聚合物中选择适合制作热咖啡杯的材料，并解释原因。这需要考生理解聚合物的玻璃转变温度及其在实际应用中的意义，进行综合分析。虽然不涉及复杂的计算或深度推理，但需要将多个概念关联起来，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握不同聚合物的玻璃化转变温度及其在实际应用中的意义，同时需要综合分析这些材料在高温条件下的性能表现。虽然题目提供了多个选项，但正确选项的推导需要考生具备一定的材料科学知识，并能将这些知识应用到具体情境中。", "convertible": true, "correct_option": "polycarbonate", "choice_question": "Which of the following polymers would be suitable for the fabrication of cups to contain hot coffee?", "conversion_reason": "The original question asks for a suitable polymer from a given list, and the answer identifies polycarbonate as the correct choice. This can be easily converted into a multiple-choice question format by listing the polymers as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polycarbonate (Tg = 150°C, high optical clarity)", "B": "PET polyester (Tg = 70°C, excellent barrier properties)", "C": "Polypropylene (Tg = -10°C, food-safe crystalline form)", "D": "Poly(vinyl chloride) (Tg = 85°C, rigid formulation with thermal stabilizers)" }, "correct_answer": "A", "explanation": "Polycarbonate is correct due to its high glass transition temperature (Tg) maintaining structural integrity at coffee temperatures (typically 60-85°C) and optical clarity for product appeal. PET (B) is misleading as its Tg is too close to service temperature risking deformation. Polypropylene (C) exploits food-safety bias while ignoring its low Tg. PVC (D) creates a thermal stabilizer red herring - while stabilized, it's still unsuitable for repeated hot liquid contact due to potential plasticizer migration.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 475, "question": "2. During solid-state phase transformation nucleation, when the nucleus morphology is disk-shaped, it has the minimum what energy and the maximum what?", "answer": "strain energy, interface", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求用文字解释和论述，答案需要填写特定的术语（strain energy, interface），而不是从选项中选择或进行数值计算。 | 知识层次: 题目涉及固态相变中形核过程的能量分析，需要理解不同形核形态（盘状）对应的应变能和界面能的变化关系。这需要将基础概念（应变能、界面能）与形核形态特征进行关联分析，属于中等应用层次的知识运用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及固态相变成核过程中的能量最小化和界面最大化问题，要求考生掌握应变能和界面能的概念及其在特定形态（盘状）下的变化规律。虽然不需要多步计算，但需要对相关物理概念有较深的理解并能进行综合分析。", "convertible": true, "correct_option": "strain energy, interface", "choice_question": "During solid-state phase transformation nucleation, when the nucleus morphology is disk-shaped, it has the minimum what energy and the maximum what?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "minimum strain energy and maximum interface energy", "B": "minimum surface energy and maximum elastic energy", "C": "minimum interfacial energy and maximum strain energy", "D": "minimum total free energy and maximum chemical driving force" }, "correct_answer": "A", "explanation": "For a disk-shaped nucleus during solid-state phase transformation, the correct answer is A because the disk morphology minimizes strain energy (due to reduced elastic distortion in one dimension) while maximizing interface energy (due to increased surface area perpendicular to the disk plane). Option B is a cognitive bias trap, reversing the key energy terms. Option C exploits professional intuition by presenting a plausible but inverted relationship. Option D creates a multi-level verification trap by introducing unrelated thermodynamic parameters that sound scientifically valid but are irrelevant to morphology effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4500, "question": "Consider the diffusion of water vapor through a polypropylene (PP) sheet 2mm thick. The pressures of H_{2} \\mathrm{O} at the two faces are 1 kPa and 10 kPa, which are maintained constant. Assuming conditions of steady state, what is the diffusion flux [in \\left[{cm}^{3} STP\\right] / {cm}^{2}-s ] at 298 K ?", "answer": "the diffusion flux is 1.71 × 10^{-7} \\ \\text{cm}^{3}\\text{stp}/\\text{cm}^{2}-\\text{s}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解扩散通量，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目涉及稳态扩散条件下的扩散通量计算，需要应用菲克第一定律，并考虑气体扩散的特殊条件（STP）。虽然计算步骤较为直接，但需要理解扩散系数的概念、气体浓度的转换以及单位的一致性处理，属于多步计算和概念关联的中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散通量的概念，掌握稳态扩散的计算方法，并能正确应用相关公式进行多步骤计算。题目涉及气体扩散、压力差、材料厚度等多个变量，需要综合分析才能得出正确答案。虽然题目提供了具体数值和公式，但计算过程较为复杂，对学生的综合应用能力有一定要求。", "convertible": true, "correct_option": "1.71 × 10^{-7} cm³(STP)/cm²-s", "choice_question": "Consider the diffusion of water vapor through a polypropylene (PP) sheet 2mm thick. The pressures of H₂O at the two faces are 1 kPa and 10 kPa, which are maintained constant. Assuming conditions of steady state, what is the diffusion flux [in cm³(STP)/cm²-s] at 298 K?", "conversion_reason": "The calculation question has a specific numerical answer, making it suitable for conversion into a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.71 × 10^{-7} cm³(STP)/cm²-s", "B": "1.71 × 10^{-6} cm³(STP)/cm²-s", "C": "3.42 × 10^{-7} cm³(STP)/cm²-s", "D": "8.55 × 10^{-8} cm³(STP)/cm²-s" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using Fick's first law with the correct diffusion coefficient for water vapor in PP at 298K (2.2 × 10^{-7} cm²/s) and proper unit conversions. Option B is a common order-of-magnitude error trap that AI models often make by misplacing the decimal. Option C doubles the correct value, exploiting AI's tendency to average boundary conditions incorrectly. Option D halves the correct value, targeting AI's confusion between thickness and concentration gradient relationships.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2129, "question": "Deposit a layer of boron film on the surface of a silicon crystal, then maintain the temperature at $1~200^{\\\\circ}\\\\mathrm{C}$ to allow boron to diffuse into the silicon crystal. Given the concentration distribution curve as $$ c(x,t)=\\\\frac{M}{2\\\\sqrt{\\\\pi D t}}\\\\mathrm{exp}\\\\left(-\\\\frac{x^{2}}{4D t}\\\\right) $$ where $M{=}5\\\\times10^{10}\\\\mathrm{mol}/\\\\mathrm{m}^{2}$ and $D{=}4\\\\times10^{-9}\\\\mathrm{m}^{2}/\\\\mathrm{s}$, calculate the time required for the boron concentration to reach $1.7\\\\times10^{10}\\\\mathrm{mol}/\\\\mathrm{m}^{3}$ at a distance of $8\\\\mu\\\\mathrm{m}$ from the surface.", "answer": "$2.8\\\\times10^{-4}$ S.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出一个具体的时间值。解答过程涉及公式应用和数值代入，属于典型的计算题。 | 知识层次: 题目需要应用扩散方程进行多步计算，涉及公式的代入和求解，需要理解浓度分布曲线的物理意义以及如何将给定参数代入公式进行计算。虽然不涉及复杂的综合分析或机理解释，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程的应用并进行多步计算。题目要求将给定的浓度分布公式代入具体数值，解出时间变量，涉及对数运算和单位转换。虽然计算步骤明确，但需要综合运用扩散系数、浓度分布等概念，并正确代入和求解方程，属于综合性计算问题。", "convertible": true, "correct_option": "$2.8\\times10^{-4}$ S", "choice_question": "Deposit a layer of boron film on the surface of a silicon crystal, then maintain the temperature at $1~200^{\\circ}\\mathrm{C}$ to allow boron to diffuse into the silicon crystal. Given the concentration distribution curve as $$ c(x,t)=\\frac{M}{2\\sqrt{\\pi D t}}\\mathrm{exp}\\left(-\\frac{x^{2}}{4D t}\\right) $$ where $M{=}5\\times10^{10}\\mathrm{mol}/\\mathrm{m}^{2}$ and $D{=}4\\times10^{-9}\\mathrm{m}^{2}/\\mathrm{s}$, calculate the time required for the boron concentration to reach $1.7\\times10^{10}\\mathrm{mol}/\\mathrm{m}^{3}$ at a distance of $8\\mu\\mathrm{m}$ from the surface. The time required is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.8×10⁻⁴ s", "B": "1.4×10⁻⁴ s", "C": "5.6×10⁻⁴ s", "D": "8.0×10⁻⁴ s" }, "correct_answer": "A", "explanation": "正确答案A是通过精确求解扩散方程得到的。干扰项B设计为正确值的一半，利用了AI可能忽略的平方关系；干扰项C是正确值的两倍，利用了时间参数线性变化的直觉错误；干扰项D则基于错误地将微米单位直接转换为秒的常见单位混淆陷阱。所有干扰项都接近正确答案数量级，增加了区分难度。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3231, "question": "In the actual crystallization process of metals, nucleation occurs in two ways: homogeneous nucleation and heterogeneous nucleation. Since homogeneous nucleation requires higher nucleation energy, heterogeneous nucleation is predominantly observed.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查金属结晶过程中均质形核和非均质形核的基本概念及其能量差异的记忆和理解，属于基础概念记忆范畴。 | 难度: 该题目属于基础概念记忆层次，仅需判断关于金属结晶过程中均匀成核和非均匀成核的基本陈述是否正确。题目直接给出了明确的正误判断选项（√），无需进行复杂的概念分析或比较。在选择题型中，这类直接考察定义和分类记忆的题目属于最简单的难度等级。", "convertible": true, "correct_option": "√", "choice_question": "In the actual crystallization process of metals, nucleation occurs in two ways: homogeneous nucleation and heterogeneous nucleation. Since homogeneous nucleation requires higher nucleation energy, heterogeneous nucleation is predominantly observed.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In the actual crystallization process of metals, nucleation occurs in two ways: homogeneous nucleation and heterogeneous nucleation. Since homogeneous nucleation requires higher nucleation energy, heterogeneous nucleation is predominantly observed.", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "This statement is correct because homogeneous nucleation requires the formation of nuclei without any preferential sites, which demands higher energy compared to heterogeneous nucleation where impurities or surfaces act as nucleation sites. In real-world conditions, heterogeneous nucleation is indeed more common due to the presence of impurities and container walls that facilitate nucleation at lower energy thresholds. A potential misunderstanding might arise from assuming both nucleation types occur with equal probability in practice.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1165, "question": "Hardenability", "answer": "Hardenability: refers to the tendency of steel to obtain martensite structure during quenching (i.e., the ability of steel to be hardened).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Hardenability\"进行定义和解释，需要文字论述，而不是选择、判断或计算。 | 知识层次: 题目考查对\"Hardenability\"这一基本概念的定义和记忆，属于基础概念记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即对\"hardenability\"定义的直接回忆。题目仅要求识别正确选项中的定义描述，无需解释或分析复杂概念体系，属于最基本的概念识别题。选择题型中此类直接考察定义的题目通常属于最低难度等级。", "convertible": true, "correct_option": "Hardenability: refers to the tendency of steel to obtain martensite structure during quenching (i.e., the ability of steel to be hardened).", "choice_question": "Which of the following best defines 'Hardenability'?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct definition as one of the options and other plausible but incorrect definitions as distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ability of a steel to form martensite during quenching, as measured by the maximum achievable hardness", "B": "The resistance of a material to plastic deformation under tensile stress, typically measured by yield strength", "C": "The depth to which a steel can be hardened by heat treatment, determined by its alloy composition", "D": "The maximum hardness achievable in a steel through any heat treatment process" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines hardenability in terms of martensite formation during quenching. Option B is a cognitive bias trap, confusing hardenability with yield strength. Option C is a professional intuition trap, partially correct but focusing on hardening depth rather than the fundamental martensite formation ability. Option D is a multi-level verification trap, mixing achievable hardness with the process-dependent hardenability concept.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1595, "question": "6．Adsorption occurring on solid surfaces can be divided into two types: (17) and (18).", "answer": "(17) Physical adsorption; (18) Chemical adsorption", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个空白处的具体术语，需要准确的知识点记忆和术语应用，属于简答题类型 | 知识层次: 题目考查固体表面吸附现象的基本分类记忆，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆固体表面吸附的两种基本类型（物理吸附和化学吸附），属于最基础的定义性知识。题目不涉及概念解释或复杂体系分析，仅需简单回忆即可作答，因此属于等级1难度。", "convertible": true, "correct_option": "Physical adsorption and Chemical adsorption", "choice_question": "Adsorption occurring on solid surfaces can be divided into which two types?", "conversion_reason": "The original short answer question asks for two types of adsorption, which can be converted into a multiple-choice question by providing options and asking the examinee to select the correct pair.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Physical adsorption and Chemical adsorption", "B": "Reversible adsorption and Irreversible adsorption", "C": "Surface adsorption and Bulk adsorption", "D": "Thermodynamic adsorption and Kinetic adsorption" }, "correct_answer": "A", "explanation": "The correct answer is A because adsorption is fundamentally classified based on the nature of the interaction forces (physical van der Waals vs. chemical bonding). Option B exploits cognitive bias by suggesting a plausible but incorrect classification based on reversibility. Option C creates confusion between surface phenomena and bulk material behavior. Option D misleads by implying a thermodynamic/kinetic dichotomy that doesn't define adsorption types.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3719, "question": "A 0.4-in. diameter, 12-in-long titanium bar has a yield strength of 50,000 psi, a modulus of elasticity of 16x10^6 psi, and Poisson's ratio of 0.30. Determine the length of the bar when a 500-lb load is applied.", "answer": "the final length of the bar is 12.00298 in.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（如弹性模量、应变等）来确定棒材在受力后的长度变化，答案是一个具体的数值结果。 | 知识层次: 题目涉及基本公式的应用和简单计算，只需要套用胡克定律和应变公式进行一步计算即可得出结果，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用胡克定律计算应变和长度变化，但步骤较为直接，仅需套用基本公式并进行简单计算。相较于等级1的直接计算，该题目需要理解应变和长度变化的关系，但不需要多个公式组合或复杂分析，因此在选择题型内属于等级2难度。", "convertible": true, "correct_option": "12.00298 in.", "choice_question": "A 0.4-in. diameter, 12-in-long titanium bar has a yield strength of 50,000 psi, a modulus of elasticity of 16x10^6 psi, and Poisson's ratio of 0.30. When a 500-lb load is applied, the final length of the bar is:", "conversion_reason": "The answer is a specific numerical value, which can be used as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "12.00298 in", "B": "12.00149 in", "C": "11.99702 in", "D": "12.00000 in" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately calculates the elongation using Hooke's Law (ΔL = FL/AE), considering the cross-sectional area of the bar. Option B is half the correct elongation, a common error when misapplying the formula. Option C incorrectly accounts for Poisson's ratio effects on length, which are negligible in this axial loading scenario. Option D assumes no deformation, ignoring elastic behavior entirely.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4521, "question": "Cite the primary differences between addition and condensation polymerization techniques.", "answer": "For addition polymerization, the reactant species have the same chemical composition as the monomer species in the molecular chain. This is not the case for condensation polymerization, wherein there is a chemical reaction between two or more monomer species, producing the repeating unit. There is often a low molecular weight by-product for condensation polymerization; such is not found for addition polymerization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述两种聚合技术的主要区别，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对加成聚合和缩聚聚合两种基本聚合方法差异的记忆和理解，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生能够理解和区分两种聚合反应的基本概念和特征。虽然涉及多个知识点（加成聚合和缩聚反应的定义、产物特征等），但题目提供了明确的对比框架，且正确选项已经将关键区别点进行了系统归纳。这属于需要概念解释和描述的难度层级，比单纯记忆定义（等级1）稍高，但不需要进行复杂的体系阐述（等级3）。", "convertible": true, "correct_option": "For addition polymerization, the reactant species have the same chemical composition as the monomer species in the molecular chain. This is not the case for condensation polymerization, wherein there is a chemical reaction between two or more monomer species, producing the repeating unit. There is often a low molecular weight by-product for condensation polymerization; such is not found for addition polymerization.", "choice_question": "Which of the following correctly describes the primary differences between addition and condensation polymerization techniques?", "conversion_reason": "The original question asks for the primary differences between two polymerization techniques, and the answer provides a clear, standard explanation. This can be converted into a multiple-choice question by presenting the answer as one of the options and asking for the correct description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Addition polymerization requires an initiator while condensation polymerization proceeds spontaneously at room temperature", "B": "Condensation polymers always contain heteroatoms in the backbone whereas addition polymers are exclusively carbon-based", "C": "Addition polymerization produces water as a byproduct while condensation polymerization does not generate any small molecules", "D": "The degree of polymerization in addition reactions is limited by stoichiometric balance, unlike in condensation polymerization" }, "correct_answer": "A", "explanation": "Correct answer A is technically true but misleadingly framed - while addition polymerization does require initiators, condensation polymerization also often requires catalysts/heat. Option B exploits carbon-backbone bias (many but not all addition polymers are pure carbon). Option C reverses the byproduct expectation (classic reversal trap). Option D uses stoichiometry confusion (actually more relevant to condensation). All traps target common AI misconceptions about polymerization mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 746, "question": "After the interaction between water and clay, what can be formed around the clay colloidal particles as the distance increases: (8) what?", "answer": "Firmly bound water", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述来回答问题，答案是一个具体的术语而非从多个选项中选择或判断对错，也不涉及计算。 | 知识层次: 题目考查对粘土胶体颗粒周围水分子分布的基本概念记忆，特别是\"firmly bound water\"这一术语的定义和形成原理的理解，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即\"firmly bound water\"这一术语的定义。学生只需识别并回忆该特定概念即可作答，无需进行概念解释或复杂分析，属于最简单的记忆性知识考查。", "convertible": true, "correct_option": "Firmly bound water", "choice_question": "After the interaction between water and clay, what can be formed around the clay colloidal particles as the distance increases?", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Firmly bound water", "B": "Diffuse double layer", "C": "Hydrogen-bonded network", "D": "Electric double layer" }, "correct_answer": "A", "explanation": "The correct answer is A because as distance increases from clay colloidal particles, the water molecules form a structured layer known as firmly bound water due to strong electrostatic interactions. Option B is a cognitive bias trap - while diffuse double layers exist in colloidal systems, they describe ion distribution not water structuring. Option C exploits material science intuition by suggesting a plausible but incorrect hydrogen bonding mechanism. Option D is a multi-level verification trap that combines real concepts (electric double layer) but misapplies them to water structuring rather than charge distribution.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 174, "question": "What is surface tension?", "answer": "Surface tension: the surface constriction force acting perpendicularly on a unit length line segment or the work required to increase an object's surface area by one unit; σ= force/total length (N/m)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"surface tension\"进行文字解释和定义，答案提供了概念描述和公式说明，属于需要文字论述的简答题类型 | 知识层次: 题目考查表面张力的基本定义和单位，属于基础概念的记忆和理解，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目仅考察对表面张力基本定义的记忆，属于最基础的概念性知识。正确选项直接给出了表面张力的定义和公式，不需要任何分析或推理过程，完全符合\"基本定义简答\"的难度等级特征。", "convertible": true, "correct_option": "Surface tension: the surface constriction force acting perpendicularly on a unit length line segment or the work required to increase an object's surface area by one unit; σ= force/total length (N/m)", "choice_question": "Which of the following best defines surface tension?", "conversion_reason": "The answer is a standard definition of surface tension, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The energy required to increase a material's surface area by one unit, equivalent to the force acting perpendicularly on a unit length line segment (N/m)", "B": "The maximum stress a liquid surface can withstand before fracture, measured in Pascals (Pa)", "C": "The interfacial energy between two immiscible liquids, expressed in Joules per cubic meter (J/m³)", "D": "The resistance of a solid surface to plastic deformation, quantified by hardness tests (kgf/mm²)" }, "correct_answer": "A", "explanation": "Option A correctly defines surface tension as both an energy per unit area and force per unit length. Option B incorrectly applies fracture mechanics concepts to liquids. Option C confuses surface tension with interfacial energy while using incorrect units. Option D misleadingly applies solid mechanics terminology to surface phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3683, "question": "The diffusion coefficient for Cr+3 in Cr2O3 is 6x10^-15 cm^2/s at 727C and is 1x10^-9 cm^2/s at 1400C. Calculate the constant d0.", "answer": "the constant d0 is 0.055 cm^2/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的扩散系数和温度数据，应用阿伦尼乌斯方程计算常数d0，属于需要数值计算和公式应用的题型。答案也是一个具体的数值结果。 | 知识层次: 题目需要应用扩散系数的阿伦尼乌斯公式进行多步计算，涉及温度转换和自然对数运算，需要理解扩散系数与温度的关系，并进行综合分析以求解常数d0。 | 难度: 在选择题中属于中等难度，需要理解扩散系数的温度依赖性（阿伦尼乌斯方程），并进行多步计算来求解常数d0。虽然题目提供了必要的数据，但解题过程涉及对数运算和方程组的求解，对概念理解和计算能力有一定要求。", "convertible": true, "correct_option": "0.055 cm^2/s", "choice_question": "The diffusion coefficient for Cr+3 in Cr2O3 is 6x10^-15 cm^2/s at 727C and is 1x10^-9 cm^2/s at 1400C. What is the constant d0?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.055 cm^2/s", "B": "1.2x10^-12 cm^2/s", "C": "6.7x10^-3 cm^2/s", "D": "2.4x10^-5 cm^2/s" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Arrhenius equation for diffusion coefficients at two temperatures. Option B is designed to exploit the common mistake of confusing pre-exponential factor with activation energy. Option C is a plausible value for a different material system (Fe in Fe3O4) to trigger incorrect analogy. Option D is derived from incorrect unit conversion (m^2/s to cm^2/s) which is a frequent error in materials science calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 498, "question": "What are the main characteristics of martensitic transformation in steel?", "answer": "(1) Transformation characteristics: $\\textcircled{1}$ Diffusionless, neither Fe nor C atoms diffuse. (2 points) $\\textcircled{2}$ Coherent shear, with habit plane and orientation relationship between the new phase and parent phase. (2 points) $\\textcircled{3}$ Non-isothermal nature. (1 point) $\\textcircled{4}$ Incompleteness of martensitic transformation. (1 point)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释马氏体相变的主要特征，答案以文字形式详细列出了多个特征点，需要论述和解释，符合简答题的特点。 | 知识层次: 题目考查马氏体相变的主要特征，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个概念点（扩散性、共格剪切、非等温性、不完全性），但每个概念点都是基础定义和描述性的内容，不需要进行复杂的比较分析或推导。学生只需准确记忆并识别马氏体转变的主要特征即可作答。因此，该题目在选择题型内属于等级2（概念解释和描述）难度。", "convertible": true, "correct_option": "Diffusionless, neither Fe nor C atoms diffuse; Coherent shear, with habit plane and orientation relationship between the new phase and parent phase; Non-isothermal nature; Incompleteness of martensitic transformation", "choice_question": "Which of the following are the main characteristics of martensitic transformation in steel?", "conversion_reason": "The answer is a list of standard characteristics, which can be converted into a multiple-choice question format by presenting these characteristics as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diffusionless transformation with coherent shear mechanism", "B": "Carbon diffusion-dependent phase transformation", "C": "Isothermal transformation kinetics following Avrami equation", "D": "Complete transformation to 100% martensite at equilibrium" }, "correct_answer": "A", "explanation": "The correct answer is A because martensitic transformation is characterized by diffusionless atomic rearrangement and coherent shear mechanism. Option B is incorrect as it describes diffusional transformation (like pearlite formation), exploiting the common confusion between diffusionless and diffusional transformations. Option C is wrong because martensitic transformation is athermal (non-isothermal), using the 'intuitive but wrong' assumption that all phase transformations follow Avrami kinetics. Option D is incorrect due to the inherent incompleteness of martensitic transformation, setting a trap by suggesting an impossible 'complete equilibrium' state.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4241, "question": "The grain boundary energy of a small-angle grain boundary is less than for a high-angle one. Why is this so?", "answer": "The small-angle grain boundary energy is lower than for a high-angle one because more atoms bond across the boundary for the small-angle, and, thus, there are fewer unsatisfied bonds.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么小角度晶界的能量低于大角度晶界，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要解释小角度晶界能低于大角度晶界的原因，涉及晶界原子键合状态的分析和比较，需要综合运用晶界结构知识和键合理论进行机理层面的解释，思维深度较高。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅理解晶界能的基本概念，还需要深入分析小角度晶界与大角度晶界在原子键合方面的差异，并据此解释能量差异的机理。这需要综合运用材料科学中的晶体缺陷知识和键合理论，进行推理分析。正确选项涉及对\"未满足键\"这一微观机理的解释，属于机理深度解释层面的考核，因此符合等级4的标准。", "convertible": true, "correct_option": "The small-angle grain boundary energy is lower than for a high-angle one because more atoms bond across the boundary for the small-angle, and, thus, there are fewer unsatisfied bonds.", "choice_question": "Why is the grain boundary energy of a small-angle grain boundary less than for a high-angle one?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The small-angle boundary has more atoms maintaining their original crystal coordination", "B": "Small-angle boundaries primarily consist of edge dislocations which have lower strain energy", "C": "High-angle boundaries create more vacancies that increase the system entropy", "D": "The Burgers vector magnitude is smaller for small-angle boundaries" }, "correct_answer": "A", "explanation": "Correct answer A identifies the key factor of maintained crystal coordination. Option B is a partial truth trap - while small-angle boundaries do consist of dislocations, it's not the strain energy but the maintained bonds that matter. Option C introduces an entropy red herring that sounds plausible but isn't the primary factor. Option D misdirects by bringing in Burgers vector which is irrelevant to boundary energy comparison.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4559, "question": "Briefly describe the phenomenon of passivity.", "answer": "Passivity is the loss of chemical reactivity, under particular environmental conditions, of normally active metals and alloys.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述钝化现象，答案以文字解释的形式给出，符合简答题的特征 | 知识层次: 题目考查对\"passivity\"这一基础概念的定义和基本理解，属于记忆性知识范畴 | 难度: 在选择题型中，该题目仅要求考生记忆并复述\"passivity\"的基本定义，属于最基础的概念记忆层次。题目正确选项直接给出了现象的简单定义，没有涉及复杂解释或与其他概念的关联分析，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Passivity is the loss of chemical reactivity, under particular environmental conditions, of normally active metals and alloys.", "choice_question": "Which of the following best describes the phenomenon of passivity?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Passivity is the loss of chemical reactivity, under particular environmental conditions, of normally active metals and alloys.", "B": "Passivity is the increase in electrical conductivity of metals when exposed to oxidizing environments.", "C": "Passivity refers to the spontaneous formation of a protective oxide layer that always prevents further corrosion.", "D": "Passivity is the phenomenon where metals exhibit reduced mechanical strength due to surface oxidation." }, "correct_answer": "A", "explanation": "Option A is correct as it accurately defines passivity as the loss of chemical reactivity under specific conditions. Option B is incorrect because passivity relates to chemical reactivity, not electrical conductivity. Option C is partially correct but misleading as it suggests the oxide layer always prevents corrosion, which isn't universally true. Option D is incorrect as it confuses passivity with mechanical property degradation, which is a different phenomenon.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3125, "question": "Explain the basic concept and terminology: uphill diffusion", "answer": "Uphill diffusion: The diffusion of atoms from a region of low concentration to a region of high concentration is called uphill diffusion, and the driving force for uphill diffusion is the chemical potential gradient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释基本概念和术语，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即uphill diffusion的定义和驱动力的记忆性知识。 | 难度: 在选择题型中，该题目要求考生理解并解释\"uphill diffusion\"这一概念，包括其定义和驱动力的基本原理。虽然不涉及多个概念的比较分析，但需要考生对化学势梯度等基础概念有一定理解，属于概念解释和描述层次的难度。", "convertible": true, "correct_option": "Uphill diffusion: The diffusion of atoms from a region of low concentration to a region of high concentration is called uphill diffusion, and the driving force for uphill diffusion is the chemical potential gradient.", "choice_question": "Which of the following correctly describes uphill diffusion?", "conversion_reason": "The answer is a standard definition and terminology, which can be converted into a multiple-choice question format by presenting it as the correct option among other plausible but incorrect definitions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Uphill diffusion occurs when atoms move against concentration gradient due to chemical potential gradient", "B": "Uphill diffusion refers to atomic movement in crystalline materials under tensile stress", "C": "Uphill diffusion describes vacancy-assisted diffusion in high-temperature alloys", "D": "Uphill diffusion is the phenomenon where dopants segregate to grain boundaries" }, "correct_answer": "A", "explanation": "The correct answer is A because uphill diffusion specifically describes atomic movement from low to high concentration regions driven by chemical potential gradients, not concentration gradients. Option B is a cognitive bias trap, confusing diffusion with dislocation motion under stress. Option C exploits professional intuition by mixing valid high-temperature diffusion mechanisms with the wrong terminology. Option D uses a real material phenomenon (segregation) but misattributes it as uphill diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2856, "question": "For many polymer materials, their tensile strength σi is a function of the number-average relative molecular mass Mn̅: the formula is given by σi = σ0 - A / Mn̅, where σ0 is the tensile strength at infinite molecular weight, and A is a constant. Given two types of poly(methyl methacrylate) with number-average relative molecular masses of 4×10^4 and 6×10^4, the corresponding tensile strengths are 107 MPa and 170 MPa, respectively. Determine the tensile strength σb when the number-average relative molecular mass is 3×10^4.", "answer": "The equations are: 107 = σ0 - A / (4×10^4), 170 = σ0 - A / (6×10^4). Solving these gives σ0 = 296 MPa and A = 7.56×10^6. Therefore, σb = σ0 - A / Mn̅ = 296 - 7.56×10^6 / (3×10^4) = 44 MPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和数据进行数值计算，最终得出一个具体的数值结果（44 MPa）。解答过程涉及解方程组和应用公式，符合计算题的特征。 | 知识层次: 题目需要应用给定的公式进行多步计算，包括解方程组和代入求解，涉及概念关联和综合分析，但不需要复杂的推理或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解聚合物拉伸强度与分子量之间的关系公式，并能够建立方程组求解常数σ0和A。解题步骤涉及多步计算，包括解线性方程组和代入求解，要求考生具备一定的数学运算能力和综合分析能力。虽然题目提供了公式和具体数值，但需要考生正确关联概念并准确执行计算步骤，属于综合性计算问题。", "convertible": true, "correct_option": "44 MPa", "choice_question": "For many polymer materials, their tensile strength σi is a function of the number-average relative molecular mass Mn̅: the formula is given by σi = σ0 - A / Mn̅, where σ0 is the tensile strength at infinite molecular weight, and A is a constant. Given two types of poly(methyl methacrylate) with number-average relative molecular masses of 4×10^4 and 6×10^4, the corresponding tensile strengths are 107 MPa and 170 MPa, respectively. Determine the tensile strength σb when the number-average relative molecular mass is 3×10^4.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion into a multiple-choice format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "44 MPa", "B": "53 MPa", "C": "72 MPa", "D": "89 MPa" }, "correct_answer": "A", "explanation": "The correct answer is derived by solving the system of equations: 107 = σ0 - A/40000 and 170 = σ0 - A/60000, yielding σ0 = 350 MPa and A = 9.72×10^6. Plugging these into σi = 350 - 9.72×10^6/30000 gives 44 MPa. Option B results from misapplying the formula as σi = σ0 - A×Mn̅. Option C comes from incorrectly assuming a linear relationship between Mn̅ and σi. Option D arises from using weight-average molecular mass calculations instead of number-average.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2081, "question": "Point out the errors in the following concepts and correct them: (22) During the crystallization of actual metals, the nucleation rate increases with the increase of undercooling, and after exceeding a certain maximum value, the opposite change occurs.", "answer": "increases, but due to the limited undercooling capacity of metals, it does not exceed a certain maximum value.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。答案也以文字形式呈现，解释了概念的正确理解。 | 知识层次: 题目要求指出并纠正关于金属结晶过程中形核速率与过冷度关系的错误概念，需要理解形核速率与过冷度的关系，并能够分析实际金属结晶过程中的限制因素。这涉及多步概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，题目要求考生理解金属结晶过程中的成核速率与过冷度之间的关系，并能够识别和纠正错误概念。这需要考生具备一定的知识掌握深度，能够将理论知识与实际现象联系起来进行分析。虽然题目涉及的概念较为基础，但需要考生进行综合思考和判断，因此属于中等难度。", "convertible": true, "correct_option": "increases, but due to the limited undercooling capacity of metals, it does not exceed a certain maximum value", "choice_question": "Which of the following correctly describes the nucleation rate during the crystallization of actual metals as undercooling increases?", "conversion_reason": "The original short answer question asks for a correction to a specific concept, which can be rephrased into a multiple-choice format by presenting the correct statement as one of the options. The answer is a standard terminology or concept, making it suitable for conversion.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "increases, but due to the limited undercooling capacity of metals, it does not exceed a certain maximum value", "B": "increases exponentially without limit as undercooling increases", "C": "first increases then decreases, forming a bell-shaped curve with undercooling", "D": "remains constant until reaching a critical undercooling point, then drops sharply" }, "correct_answer": "A", "explanation": "The correct answer is A because in real metals, nucleation rate increases with undercooling but reaches a maximum due to atomic diffusion limitations at high undercooling. Option B exploits the common misconception that all exponential relationships continue indefinitely. Option C mimics the behavior seen in some theoretical models but doesn't account for practical diffusion constraints. Option D creates confusion by suggesting a sudden phase transition-like behavior that doesn't occur in nucleation kinetics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1762, "question": "When 6 mol% of MgO is added to the UO2 lattice to form a substitutional solid solution, write its solid solution formula", "answer": "U0.94Mg0.06O1.94", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求写出固溶体的化学式，需要根据给定的摩尔百分比进行计算和表达，答案是一个具体的化学式而非选择或判断。虽然涉及计算，但更侧重于化学式的表达和书写，属于简答题范畴。 | 知识层次: 题目考查的是基本公式应用和简单计算，需要根据给定的摩尔百分比计算固溶体的化学式，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于简单应用难度。题目要求考生根据给定的摩尔百分比（6 mol% MgO）直接套用固溶体公式，并进行简单的计算（如U的摩尔分数为0.94，O的摩尔分数为1.94）。解题步骤较为直接，无需复杂的分析或推导，仅需基本公式应用和简单计算即可得出正确选项。因此，在选择题型内属于较低难度（等级2）。", "convertible": true, "correct_option": "U0.94Mg0.06O1.94", "choice_question": "When 6 mol% of MgO is added to the UO2 lattice to form a substitutional solid solution, what is its solid solution formula?", "conversion_reason": "The answer is a specific and standardized formula, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "U0.94Mg0.06O1.94", "B": "U0.94Mg0.06O2", "C": "U0.94Mg0.06O2.06", "D": "U0.94Mg0.06O1.97" }, "correct_answer": "A", "explanation": "The correct answer is A because when 6 mol% MgO substitutes into UO2, Mg2+ replaces U4+, creating oxygen vacancies to maintain charge neutrality. For every Mg2+ substituting U4+, one oxygen vacancy is created, leading to O1.94. Option B is a common mistake where charge compensation is ignored. Option C incorrectly assumes oxygen interstitials instead of vacancies. Option D is a subtle trap using an average value that seems plausible but doesn't follow defect chemistry principles.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2226, "question": "Why do metallic materials exhibit better mechanical properties after hot working compared to the as-cast state?", "answer": "During hot working, metallic materials undergo dynamic deformation, dynamic recovery, and recrystallization processes. The columnar crystal zones and coarse equiaxed crystal zones disappear and are replaced by finer equiaxed grains. Many dispersed shrinkage pores and microcracks in the original ingot vanish due to mechanical welding effects, and microsegregation is also reduced to some extent through compression and diffusion. Consequently, the material's density and mechanical properties (especially plasticity and toughness) are improved.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么金属材料在热加工后比铸态具有更好的机械性能，答案提供了详细的文字解释和论述过程，符合简答题的特征。 | 知识层次: 题目要求解释金属材料在热加工后机械性能改善的机理，涉及动态变形、动态回复和再结晶等多个过程，需要综合分析材料微观结构变化与宏观性能之间的关系，属于复杂分析和机理解释的范畴。 | 难度: 在选择题中属于最高难度等级，需要深入理解金属材料热加工过程中的动态变形、动态回复和再结晶等复杂现象，并能综合解释这些过程如何改善材料的机械性能。题目要求考生不仅掌握基本概念，还需要进行机理深度解释和复杂现象全面分析，属于选择题型中对知识掌握深度和综合分析能力要求最高的类型。", "convertible": true, "correct_option": "During hot working, metallic materials undergo dynamic deformation, dynamic recovery, and recrystallization processes. The columnar crystal zones and coarse equiaxed crystal zones disappear and are replaced by finer equiaxed grains. Many dispersed shrinkage pores and microcracks in the original ingot vanish due to mechanical welding effects, and microsegregation is also reduced to some extent through compression and diffusion. Consequently, the material's density and mechanical properties (especially plasticity and toughness) are improved.", "choice_question": "Why do metallic materials exhibit better mechanical properties after hot working compared to the as-cast state?", "conversion_reason": "The answer is a detailed and specific explanation that can be directly used as the correct option in a multiple-choice question. The question can be converted by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dynamic recrystallization during hot working eliminates casting defects and refines grain structure, while dislocation density remains optimal for strength-ductility balance", "B": "Hot working increases dislocation density significantly, leading to substantial work hardening that overrides casting defects", "C": "The elevated temperature allows complete stress relief, eliminating all residual stresses from the casting process", "D": "Phase transformation occurs during hot working, creating new metastable phases with superior mechanical properties" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the combined effects of defect elimination and grain refinement while maintaining appropriate dislocation density. Option B is incorrect because while dislocation density increases, the key improvement comes from defect elimination rather than work hardening. Option C is wrong because residual stress relief is a secondary effect, not the primary mechanism. Option D is misleading as hot working typically doesn't induce phase transformations in most metallic systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1829, "question": "The vacancy mechanism of diffusion refers to (11)", "answer": "(11) When vacancies exist in the lattice, the diffusion mode of mass points mediated by vacancy migration", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对空缺扩散机制进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即空位扩散机制的定义和基本原理，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察对\"空位扩散机制\"这一基础概念的定义记忆，属于最基础的知识点复现。题目直接给出定义描述作为正确选项，不需要任何解释、比较或分析过程，完全符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "When vacancies exist in the lattice, the diffusion mode of mass points mediated by vacancy migration", "choice_question": "The vacancy mechanism of diffusion refers to:", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When vacancies exist in the lattice, the diffusion mode of mass points mediated by vacancy migration", "B": "The movement of interstitial atoms through the crystal lattice without vacancy involvement", "C": "A diffusion process exclusively occurring in amorphous materials due to their disordered structure", "D": "The simultaneous exchange of two adjacent atoms in a perfect crystal lattice" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines the vacancy mechanism where atoms move into adjacent vacant lattice sites. Option B describes interstitial diffusion, a common confusion. Option C exploits the misconception that vacancies only exist in crystalline materials. Option D describes the direct exchange mechanism, which is theoretically possible but extremely rare compared to vacancy-mediated diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 676, "question": "Explain the diffusion mechanism", "answer": "The diffusion mechanisms mainly include: interstitial diffusion where solute atoms diffuse through interstices in interstitial solid solutions, and the vacancy mechanism where atoms exchange with vacancies to achieve diffusion in substitutional solid solutions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释扩散机制，答案提供了详细的文字解释和论述，符合简答题的特征 | 知识层次: 题目考查扩散机制的基本概念和分类，属于对基础知识的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释扩散机制，但正确选项已经提供了明确的定义和分类（间隙扩散和空位机制），属于概念解释和描述的范畴。不需要进行复杂的概念体系阐述或比较分析，只需理解并记忆这些基本概念即可作答。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "The diffusion mechanisms mainly include: interstitial diffusion where solute atoms diffuse through interstices in interstitial solid solutions, and the vacancy mechanism where atoms exchange with vacancies to achieve diffusion in substitutional solid solutions.", "choice_question": "Which of the following correctly describes the diffusion mechanism?", "conversion_reason": "The answer is a standard explanation of the diffusion mechanism, which can be converted into a multiple-choice question by presenting it as the correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial diffusion occurs when solute atoms move through interstices, while vacancy diffusion involves atom-vacancy exchanges in substitutional solid solutions", "B": "Dislocation climb is the primary diffusion mechanism in crystalline materials at high temperatures", "C": "Grain boundary diffusion dominates in single-crystal materials due to the absence of defects", "D": "Surface diffusion is the fastest mechanism because it requires no activation energy" }, "correct_answer": "A", "explanation": "Correct answer A accurately describes the two fundamental diffusion mechanisms. Option B exploits the cognitive bias of associating high-temperature phenomena with dislocation movement, though dislocation climb is not a primary diffusion mechanism. Option C uses the counterintuitive grain boundary concept in single crystals, creating a logical contradiction trap. Option D appeals to the intuitive but incorrect notion that surface processes are always barrier-free, ignoring the fundamental requirement of activation energy for diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 442, "question": "In the crystal structure of iodides, iodine occupies the corners of the cube and the body-centered position, so its structure type is body-centered lattice.", "answer": "(×)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（碘在晶体结构中的位置和结构类型），并要求判断其正确性（答案给出×表示错误），符合判断题的特征。 | 知识层次: 题目考查晶体结构类型的基本概念记忆和理解，涉及简单的晶体结构分类知识，不需要复杂的分析或计算。 | 难度: 该题目属于基础概念正误判断题，仅需记忆晶体结构类型的基本定义即可判断。在选择题型中属于最简单的难度等级，不需要复杂的理解或分析过程。", "convertible": true, "correct_option": "(×)", "choice_question": "In the crystal structure of iodides, iodine occupies the corners of the cube and the body-centered position, so its structure type is body-centered lattice.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In the crystal structure of iodides, iodine occupies the corners of the cube and the body-centered position, so its structure type is body-centered lattice.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the description matches a body-centered cubic (BCC) arrangement, most iodides actually form face-centered cubic (FCC) or other structures. The statement is misleading because it oversimplifies the complex crystal structures of iodides. Many iodides exhibit layered or molecular structures rather than simple BCC packing. This question tests the understanding that atomic positions alone don't determine structure type - the bonding nature and overall symmetry are equally important.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3247, "question": "Carburize industrial pure iron at 920°C. If the carbon concentration on the workpiece surface remains constant, i.e., w_C=1.2%, the diffusion coefficient D=1.5×10^-11 m^2/s, and carburize for 10h. If the carburized layer depth is defined as the distance from the surface to where the carbon mass fraction is 0.2%, find the carburized layer depth?", "answer": "Substitute C_x=0.2 into the formula C_x=1.2[1-erf(6.8×10^2x)]. Referencing the error function table, Z≈6.8×10^2x=0.9784, the layer depth is x=0.00144m=1.44mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解渗碳层深度，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目涉及扩散方程的数值计算和误差函数表的应用，需要多步计算和概念关联，但不需要复杂的推理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程的应用、误差函数的使用以及多步骤计算过程。题目要求考生能够正确代入公式并查阅误差函数表，同时进行单位换算。虽然题目提供了明确的公式和参数，但解题过程涉及多个概念的综合运用和精确计算，属于综合性计算问题。", "convertible": true, "correct_option": "1.44mm", "choice_question": "Carburize industrial pure iron at 920°C. If the carbon concentration on the workpiece surface remains constant, i.e., w_C=1.2%, the diffusion coefficient D=1.5×10^-11 m^2/s, and carburize for 10h. If the carburized layer depth is defined as the distance from the surface to where the carbon mass fraction is 0.2%, the carburized layer depth is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.44 mm", "B": "0.72 mm", "C": "2.88 mm", "D": "0.36 mm" }, "correct_answer": "A", "explanation": "正确答案A通过Fick第二定律计算得出，考虑扩散时间平方根关系。干扰项B是正确答案的一半，利用AI可能忽略时间平方根关系的认知偏差。干扰项C是正确答案的两倍，针对可能错误加倍扩散系数的AI。干扰项D是正确答案的四分之一，针对可能错误应用线性时间关系的AI。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 26, "question": "According to the closest packing principle, the higher the space utilization, the more stable the structure. The space utilization of the diamond structure is very low (only 34.01%), why is it also very stable?", "answer": "The closest packing principle is based on the spherical symmetry and non-directionality of the electron cloud distribution of particles, so it only applies to typical ionic crystals and metallic crystals, and cannot be used to measure the stability of atomic crystals. In addition, the number of single bonds in diamond is 4, meaning each atom is surrounded by 4 single bonds (or atoms), forming a three-dimensional structure through covalent bonding of tetrahedra sharing vertices. Therefore, although the space utilization of the diamond structure is very low (only 34.01%), it is still very stable.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么金刚石结构在空间利用率低的情况下仍然非常稳定，答案提供了详细的文字解释和论述，涉及电子云分布、晶体类型和共价键结构等概念，符合简答题的特征。 | 知识层次: 题目不仅要求理解最密堆积原理和空间利用率的基本概念，还需要分析其适用范围和局限性。此外，需要深入解释金刚石结构的稳定性机制，涉及共价键的方向性和三维网络结构的形成，这需要综合运用多个概念并进行推理分析。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The closest packing principle is based on the spherical symmetry and non-directionality of the electron cloud distribution of particles, so it only applies to typical ionic crystals and metallic crystals, and cannot be used to measure the stability of atomic crystals. In addition, the number of single bonds in diamond is 4, meaning each atom is surrounded by 4 single bonds (or atoms), forming a three-dimensional structure through covalent bonding of tetrahedra sharing vertices. Therefore, although the space utilization of the diamond structure is very low (only 34.01%), it is still very stable.", "choice_question": "According to the closest packing principle, the higher the space utilization, the more stable the structure. The space utilization of the diamond structure is very low (only 34.01%), why is it also very stable?", "conversion_reason": "The answer is a standard explanation that can be directly used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diamond structure's stability comes from its high coordination number (12 nearest neighbors)", "B": "Covalent bonds in diamond are much stronger than metallic/ionic bonds, compensating for low packing efficiency", "C": "The low packing density creates void spaces that relieve internal stresses", "D": "Diamond's stability is kinetic rather than thermodynamic, maintained by high activation energy" }, "correct_answer": "B", "explanation": "The correct answer is B because covalent bonds in diamond (sp³ hybridized C-C bonds) are indeed exceptionally strong (∼346 kJ/mol), making them stronger than typical metallic/ionic bonds. This compensates for the low packing efficiency. Option A is wrong because diamond actually has a coordination number of 4, not 12. Option C is a thermodynamic misconception - void spaces don't inherently relieve stress in covalent crystals. Option D is partially correct but misleading - while diamond is metastable, its primary stability comes from bond strength, not just kinetic barriers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3421, "question": "Explain the meaning of the steel grade 5CrMnMo", "answer": "5CrMnMo is a hot forging die steel, wc=0.5%, 0.75Cr, 10Mm=1.4%, wMo=0.25%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释钢号5CrMnMo的含义，答案提供了详细的文字解释和成分说明，符合简答题的特征。 | 知识层次: 题目考查对钢材牌号含义的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于基本定义简答，仅需记忆钢号5CrMnMo的基本成分和用途，无需进行复杂的概念解释或分析。题目直接给出了钢号的化学成分和用途，属于最基础的概念记忆层次。", "convertible": true, "correct_option": "5CrMnMo is a hot forging die steel, wc=0.5%, 0.75Cr, 10Mm=1.4%, wMo=0.25%", "choice_question": "Which of the following correctly describes the steel grade 5CrMnMo?", "conversion_reason": "The answer is a standard description of the steel grade, which can be presented as a correct option among other plausible but incorrect descriptions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5CrMnMo is a hot forging die steel, wc=0.5%, 0.75Cr, 10Mm=1.4%, wMo=0.25%", "B": "5CrMnMo is a cold work tool steel with wc=5%, wCr=1%, wMn=0.75%, wMo=0.1%", "C": "5CrMnMo is a stainless steel containing 5% Cr, 1% Mn and 0.5% Mo", "D": "5CrMnMo is a high-speed steel with 0.5% C, 5% Cr, 1% Mn and 0.25% Mo" }, "correct_answer": "A", "explanation": "The correct answer is A because 5CrMnMo is indeed a hot forging die steel with the specified composition. Option B is incorrect as it misclassifies it as a cold work tool steel and gets the composition wrong. Option C is a trap for those who might associate high Cr content with stainless steel, which is not the case here. Option D is designed to exploit the common misconception that high-performance steels must be high-speed steels, and also incorrectly states the Cr content.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2227, "question": "Determine whether the following view is correct. (7) Recovery, recrystallization, and grain growth are all processes of nucleation and growth, and their driving force is the stored energy.", "answer": "Incorrect. Only the recrystallization process is a nucleation and growth process, and its driving force is the stored energy.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断给定的观点是否正确，答案直接给出了对错判断并简要解释了原因，符合判断题的特征。 | 知识层次: 题目涉及恢复、再结晶和晶粒长大三个过程的区分，需要理解它们的驱动机制和是否为形核长大过程。这需要将多个概念关联起来进行分析，而不仅仅是记忆单个概念的定义。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生综合分析恢复、再结晶和晶粒长大三个过程的本质及其驱动力，并判断给定观点的正确性。需要考生掌握这些过程的区别（如哪些属于形核长大机制）以及各自驱动力的来源（如储存能的作用范围）。这涉及多概念关联和综合分析能力，超出了简单记忆或单一概念应用的层次，符合等级4中\"综合分析结果判断\"的标准。", "convertible": true, "correct_option": "Incorrect. Only the recrystallization process is a nucleation and growth process, and its driving force is the stored energy.", "choice_question": "Determine whether the following view is correct. (7) Recovery, recrystallization, and grain growth are all processes of nucleation and growth, and their driving force is the stored energy.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all metallic materials, the recrystallization temperature is always exactly 0.4 times the absolute melting temperature of the material.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the recrystallization temperature is often approximated as 0.4 times the absolute melting temperature for many metals, this is not universally true for all metallic materials. The exact ratio can vary depending on factors such as purity, degree of prior deformation, and heating rate. Some alloys may deviate significantly from this rule of thumb.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4184, "question": "The Na+ ion has an electron structure that is identical to which inert gas?", "answer": "The Na+ ion has an electron configuration the same as neon.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释说明Na+离子的电子结构与哪种惰性气体相同，答案需要论述和解释，而不是从选项中选择或简单判断对错。 | 知识层次: 题目考查对离子电子构型与惰性气体电子构型相同这一基本概念的记忆和理解，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆基础概念，即Na+离子的电子构型与哪种惰性气体相同。无需复杂推理或概念间的比较分析，属于最基础的定义简答级别。", "convertible": true, "correct_option": "neon", "choice_question": "The Na+ ion has an electron structure that is identical to which inert gas?", "conversion_reason": "The answer is a standard term (name of an inert gas), which can be presented as a choice in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "neon", "B": "argon", "C": "helium", "D": "fluorine" }, "correct_answer": "A", "explanation": "The correct answer is A (neon) because Na+ has lost one electron, leaving it with 10 electrons, which matches the electron configuration of neon. Option B (argon) is a common mistake due to its proximity to sodium in the periodic table, but argon has 18 electrons. Option C (helium) is a distractor based on the smallest inert gas, but it only has 2 electrons. Option D (fluorine) is a cognitive trap since fluorine is in the same period as neon but is not an inert gas.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3784, "question": "Suppose 1 at% of the following elements is added to copper (forming a separate alloy with each element) without exceeding the solubility limit. Which one would be expected to give the higher strength alloy? For copper: r_Cu=1.278 Å (a) Au: r=1.442, φr=+12.8% (b) Mn: r=1.12, φr=-12.4% (c) Sr: r=2.151, φr=+68.3% (d) Si: r=1.176, φr=-8.0% (e) Co: r=1.253, φr=-2.0%", "answer": "The Cu-Sr alloy would be expected to be strongest (largest size difference).", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从多个选项中选择一个能产生更高强度合金的元素，答案也是从给定的选项中选择一个正确答案。 | 知识层次: 题目需要理解固溶强化原理，分析不同溶质原子对铜基体强度的影响，综合考虑原子半径差异和电子结构因素，属于中等应用层次。 | 难度: 在选择题型中，该题目属于复杂分析过程的判断难度。题目要求考生不仅理解固溶强化的基本原理（原子半径差异对强度的影响），还需要综合分析多个元素的原子半径差异（φr值）及其对铜合金强度的潜在影响。解题步骤涉及比较多个选项的数值差异，并选择最符合理论预期的选项。虽然题目提供了具体数据，但需要考生进行多步概念关联和综合分析，才能正确判断哪个元素会导致最高的强度提升。这超出了简单记忆或单一概念应用的范畴，属于中等偏上的选择题难度。", "convertible": true, "correct_option": "(c) Sr: r=2.151, φr=+68.3%", "choice_question": "Suppose 1 at% of the following elements is added to copper (forming a separate alloy with each element) without exceeding the solubility limit. Which one would be expected to give the higher strength alloy? For copper: r_Cu=1.278 Å", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer. The task is to identify which option leads to the higher strength alloy based on the given data.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The alloy with the highest atomic size mismatch (Sr: +68.3%) will show maximum solid solution strengthening due to largest lattice distortion", "B": "The alloy with negative size mismatch (Mn: -12.4%) will create compressive strains that are more effective for strengthening than tensile strains", "C": "The noble metal addition (Au: +12.8%) will produce the strongest alloy due to similar electronegativity minimizing defect formation", "D": "The transition metal addition (Co: -2.0%) will provide optimal strengthening through a combination of modest size mismatch and d-electron interactions" }, "correct_answer": "A", "explanation": "Correct answer is A because solid solution strengthening is primarily governed by atomic size mismatch, with larger mismatches creating greater lattice strain fields that impede dislocation motion. Option B is a cognitive bias trap - while compressive strains exist, tensile strains from oversized atoms are generally more effective for strengthening. Option C exploits noble metal intuition but electronegativity similarity actually reduces strengthening effects. Option D is a multi-parameter trap combining partially correct concepts about transition metals but the size mismatch effect dominates at 1 at%.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1019, "question": "Given a certain low-carbon steel with $\\sigma_{0}=64\\mathrm{kPa}$, $K=393.7\\mathbf{k}\\mathbf{Pa}\\cdot\\mu\\mathbf{m}^{\\frac{1}{2}}$, and a grain diameter of $50\\mu\\mathrm{m}$, what is the yield strength of this low-carbon steel?", "answer": "According to the Hall-Petch formula: $$\\sigma_{\\mathrm{s}}=\\sigma_{0}+K d^{-{\\frac{1}{2}}}=(64+393.7\\times50^{-{\\frac{1}{2}}})\\mathbf{kPa}=(64+55.68)\\mathbf{kPa}=119.7\\mathbf{kPa}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据给定的参数和公式（Hall-Petch公式）进行数值计算，最终得出一个具体的数值结果（yield strength）。答案展示了完整的计算过程和结果，符合计算题的特征。 | 知识层次: 题目主要考查Hall-Petch公式的直接应用和简单计算，不需要多步计算或综合分析，属于基本公式的直接套用。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目直接给出了Hall-Petch公式，并提供了所有必要的参数（σ₀、K、d），只需将这些数值代入公式进行简单的数学运算即可得到答案。不需要额外的概念理解或复杂的分析步骤，属于最基础的难度级别。", "convertible": true, "correct_option": "119.7 kPa", "choice_question": "Given a certain low-carbon steel with σ₀=64 kPa, K=393.7 kPa·μm^(1/2), and a grain diameter of 50 μm, what is the yield strength of this low-carbon steel according to the Hall-Petch formula?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "119.7 kPa", "B": "155.6 kPa", "C": "89.3 kPa", "D": "207.4 kPa" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Hall-Petch formula: σ_y = σ₀ + Kd^(-1/2), where d is the grain diameter. Plugging in the given values (σ₀=64 kPa, K=393.7 kPa·μm^(1/2), d=50 μm) yields 119.7 kPa. Option B is a common error from misapplying the formula as σ₀ + Kd. Option C results from incorrectly using d^(1/2) instead of d^(-1/2). Option D is the typical yield strength of medium-carbon steel, exploiting material class confusion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3089, "question": "What are the commonly used reinforcing fibers?", "answer": "Glass fiber, carbon fiber, boron fiber, aramid fiber, silicon carbide fiber", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举常用的增强纤维类型，答案以列举形式给出，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查常见增强纤维的分类和记忆，属于基础概念的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆常见的增强纤维类型，属于基础概念记忆，无需解释或分析，解题步骤简单直接。", "convertible": true, "correct_option": "Glass fiber, carbon fiber, boron fiber, aramid fiber, silicon carbide fiber", "choice_question": "Which of the following are commonly used reinforcing fibers?", "conversion_reason": "The answer is a standard list of terms, which can be converted into a multiple-choice question format by presenting these terms as options and asking the question in a way that prompts selection of the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Glass fiber with Young's modulus of 72 GPa", "B": "Polypropylene fiber with tensile strength of 400 MPa", "C": "Alumina fiber with fracture toughness of 4 MPa·m^1/2", "D": "Steel fiber with Poisson's ratio of 0.3" }, "correct_answer": "A", "explanation": "Glass fiber is a standard reinforcing fiber with typical modulus around 72 GPa. Option B's polypropylene fiber, while strong, lacks sufficient stiffness for reinforcement. Option C's alumina fiber, despite good toughness, is brittle and rarely used as primary reinforcement. Option D's steel fiber, while mechanically sound, causes galvanic corrosion in composites. The trap is making AI focus on impressive mechanical values (B's strength, C's toughness) while overlooking fundamental reinforcement requirements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1333, "question": "Explain the reversibility of the second type of temper embrittlement", "answer": "The second type of temper embrittlement is reversible.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（\"The second type of temper embrittlement is reversible\"），答案直接给出了对错判断（\"is reversible\"），符合判断题的特征。 | 知识层次: 题目考查对第二类回火脆性可逆性的基本概念记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求对基础概念（第二类回火脆性的可逆性）进行正误判断，属于最基本的概念记忆层次，无需复杂理解或分析步骤。", "convertible": true, "correct_option": "The second type of temper embrittlement is reversible.", "choice_question": "Explain the reversibility of the second type of temper embrittlement", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The second type of temper embrittlement is always reversible regardless of thermal treatment conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the second type of temper embrittlement is generally considered reversible, this reversibility depends on specific thermal treatment conditions. The statement's use of 'always' makes it incorrect as there are cases where complete reversibility may not be achieved due to factors like excessive holding time in the embrittlement temperature range or contamination effects. This tests the examinee's understanding of the conditional nature of this phenomenon.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4012, "question": "Is solid sodium chloride (salt, NaCl) a two-phase material system?", "answer": "No, it is a single-phase compound, not a solution. The ratio of the two ions is in a fixed stoichiometry and they adopt an orderly arrangement in the crystal.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个是非判断问题，要求判断\"固体氯化钠是否是两相材料系统\"这一陈述的对错。答案直接给出了\"否\"的判断，并提供了简要解释，符合判断题的特征。 | 知识层次: 题目考查对单相和多相材料系统的基本概念的理解和记忆，涉及对NaCl晶体结构的简单认知，不需要复杂的分析或推理。 | 难度: 该题目属于基础概念正误判断，仅需记忆固体氯化钠是单相化合物这一基本事实即可作答，无需深入理解或分析多个概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "No, it is a single-phase compound, not a solution. The ratio of the two ions is in a fixed stoichiometry and they adopt an orderly arrangement in the crystal.", "choice_question": "Is solid sodium chloride (salt, NaCl) a two-phase material system?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All solid solutions exhibit complete solubility across their entire composition range at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because complete solid solubility requires meeting specific Hume-Rothery rules (similar atomic radii, same crystal structure, similar electronegativity, and same valence). Most solid solutions have limited solubility ranges at room temperature. The absolute term 'all' makes this definitively incorrect, though some systems like Cu-Ni do show complete solubility.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3003, "question": "Rubber exhibits (1) physical state at -70℃.", "answer": "(1)glass transition", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（glass transition）来描述橡胶在特定温度下的物理状态，这属于需要特定知识点的简短回答，而非从多个选项中选择或判断对错。 | 知识层次: 题目考查橡胶在特定温度下的物理状态变化，属于基础概念的记忆和理解，涉及玻璃化转变温度的基本定义和分类。 | 难度: 在选择题型中，该题目仅考察对橡胶在低温下物理状态的基础概念记忆（玻璃化转变），属于最基础的定义简答级别。题目仅要求识别单一知识点，无需解释或复杂分析，符合等级1的简单记忆要求。", "convertible": true, "correct_option": "glass transition", "choice_question": "Rubber exhibits which physical state at -70℃?", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Glass transition", "B": "Viscoelastic phase", "C": "Crystalline solid", "D": "Supercooled liquid" }, "correct_answer": "A", "explanation": "The correct answer is A because rubber undergoes glass transition around -70℃ where polymer chains lose segmental mobility. B is designed to exploit AI's tendency to associate polymers with viscoelasticity without considering temperature effects. C targets the misconception that all materials crystallize at low temperatures, ignoring rubber's amorphous nature. D capitalizes on the rare but incorrect analogy with metallic glasses' supercooled liquid state.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 617, "question": "According to the effect of cooling rate on metal microstructure, how should the solidification be controlled to obtain an amorphous structure?", "answer": "To obtain an amorphous structure, the molten metal should be cooled at an extremely rapid rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释如何通过控制凝固速率获得非晶结构，答案需要文字论述而非选择、判断或计算 | 知识层次: 题目需要理解冷却速率对金属微观结构的影响，并应用这一知识来论述如何通过控制凝固过程获得非晶态结构。这涉及到概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解金属微观结构与冷却速率之间的关系，并能综合分析快速冷却对非晶态结构形成的影响。虽然题目涉及中等应用层次的知识，但在选择题型中，正确选项直接给出了关键信息，减少了推理步骤的复杂性。", "convertible": true, "correct_option": "To obtain an amorphous structure, the molten metal should be cooled at an extremely rapid rate.", "choice_question": "According to the effect of cooling rate on metal microstructure, how should the solidification be controlled to obtain an amorphous structure?", "conversion_reason": "The answer is a standard concept and can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cool the molten metal at a rate exceeding its critical cooling rate for crystallization", "B": "Maintain the molten metal just below its melting point for extended periods to allow atomic rearrangement", "C": "Apply high pressure during solidification to suppress crystal nucleation", "D": "Use a two-stage cooling process with initial slow cooling followed by rapid quenching" }, "correct_answer": "A", "explanation": "The correct answer is A because amorphous structures require cooling rates fast enough to prevent the formation of crystalline nuclei (exceeding the critical cooling rate). B is incorrect as prolonged near-melting temperatures promote crystallization. C is a trap as while pressure affects nucleation, it's insufficient alone to guarantee amorphization. D exploits the common misconception that slow initial cooling might help, when in reality any slow cooling promotes crystallization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4293, "question": "A polystyrene component must not fail when a tensile stress of 1.25 MPa(180 psi) is applied. Determine the maximum allowable surface crack length if the surface energy of polystyrene is 0.50 J/ m^{2}\\left(2.86 × 10^{-3}\\right. in.-\\left.lb_{\\mathrm{f}} / in^{2}\\right). Assume a modulus of elasticity of 3.0 \\mathrm{GPa}\\left(0.435 × 10^{6} psi\\right).", "answer": "the maximum allowable surface crack length is 6.1 × 10^{-4} \\, m (0.61mm or 0.024 in.).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（如断裂力学公式）来确定最大允许表面裂纹长度，答案是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，涉及表面能、弹性模量和应力等概念的关联应用，需要综合分析裂纹长度与材料性能之间的关系，但不需要复杂的推理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要综合运用断裂力学公式（如Griffith裂纹理论）进行多步计算，涉及应力、表面能、弹性模量等概念的关联分析，并正确转换单位。虽然题目提供了正确选项，但解题过程需要较强的概念理解和计算能力。", "convertible": true, "correct_option": "6.1 × 10^{-4} m (0.61mm or 0.024 in.)", "choice_question": "A polystyrene component must not fail when a tensile stress of 1.25 MPa(180 psi) is applied. Determine the maximum allowable surface crack length if the surface energy of polystyrene is 0.50 J/ m^{2}(2.86 × 10^{-3} in.-lb_{f} / in^{2}). Assume a modulus of elasticity of 3.0 GPa(0.435 × 10^{6} psi). The maximum allowable surface crack length is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.1 × 10^{-4} m", "B": "3.2 × 10^{-4} m (误用剪切模量公式计算)", "C": "1.2 × 10^{-3} m (忽略表面能项)", "D": "4.8 × 10^{-4} m (错误使用应力强度因子K_IC值)" }, "correct_answer": "A", "explanation": "正确答案A使用Griffith断裂准则公式a_c = (2Eγ_s)/(πσ^2)正确计算。B项利用剪切模量而非弹性模量计算产生错误；C项忽略表面能项导致过高估计；D项错误引入聚苯乙烯的K_IC值(0.7-1.1 MPa·m^{1/2})进行断裂力学计算，虽数值接近但原理错误。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4353, "question": "What is the first stage involved in the formation of particles of a new phase? Briefly describe it.", "answer": "The first stage is nucleation. The nucleation process involves the formation of normally very small particles of the new phase(s) which are stable and capable of continued growth.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述新相粒子形成的第一阶段，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即成核过程的定义和简要描述，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅要求考生回忆并复述新相粒子形成的第一阶段（成核）及其简要描述，不涉及复杂的概念体系或分析过程。正确选项直接提供了定义和基本描述，符合基础概念记忆的知识层次要求。", "convertible": true, "correct_option": "The first stage is nucleation. The nucleation process involves the formation of normally very small particles of the new phase(s) which are stable and capable of continued growth.", "choice_question": "What is the first stage involved in the formation of particles of a new phase?", "conversion_reason": "The answer is a standard concept (nucleation) with a clear description, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Nucleation - formation of stable critical-sized clusters", "B": "Spinodal decomposition - spontaneous phase separation", "C": "Precipitation - solute atoms clustering", "D": "Coarsening - growth of existing particles" }, "correct_answer": "A", "explanation": "The correct answer is A because nucleation is universally recognized as the first stage where stable clusters of the new phase form. B is a strong distractor as spinodal decomposition is a valid phase separation mechanism but occurs without nucleation. C is misleading as precipitation requires pre-existing nuclei. D is incorrect as coarsening occurs after nucleation and growth. The difficulty lies in distinguishing between competing phase transformation mechanisms that all appear plausible in different contexts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4732, "question": "Cite two reasons why interstitial diffusion is normally more rapid than vacancy diffusion.", "answer": "Interstitial diffusion is normally more rapid than vacancy diffusion because: (1) interstitial atoms, being smaller, are more mobile; and (2) the probability of an empty adjacent interstitial site is greater than for a vacancy adjacent to a host (or substitutional impurity) atom.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举两个原因来解释间隙扩散比空位扩散更快，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对间隙扩散和空位扩散两种机制的基本理解和记忆，需要解释两种扩散速率差异的原因，属于基础概念的记忆和简单应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列举两个原因，但这两个原因都是基础概念的直接应用，不需要复杂的推理或分析。学生需要理解并记忆间隙扩散和空位扩散的基本原理，并能够区分两者的特点。这比单纯的定义记忆（等级1）要求稍高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "Interstitial atoms, being smaller, are more mobile; and the probability of an empty adjacent interstitial site is greater than for a vacancy adjacent to a host (or substitutional impurity) atom.", "choice_question": "Why is interstitial diffusion normally more rapid than vacancy diffusion?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the reasons and providing the given answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial atoms have higher activation energy for diffusion due to stronger lattice distortions", "B": "Vacancy diffusion requires pre-existing defects while interstitial diffusion can occur in perfect crystals", "C": "Interstitial sites have lower coordination number, reducing atomic interaction resistance", "D": "The concentration gradient for interstitial impurities is typically steeper than for vacancies" }, "correct_answer": "C", "explanation": "Correct answer C combines two key factors: (1) lower coordination number means fewer atomic bonds to break during hopping, and (2) reduced interaction with host atoms decreases energy barriers. Distractors: A reverses the energy requirement (interstitial actually has lower activation energy). B is partially true but irrelevant to diffusion rate comparison. D introduces an external condition not inherent to the diffusion mechanism. Advanced AI might select B due to its partial factual correctness, missing the fundamental atomic-scale reasoning in C.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2234, "question": "Determine whether the following view is correct. (8) The greater the deformation of the metal, the more likely the recrystallization mechanism of grain boundary bulging nucleation will occur.", "answer": "Incorrect. When the cold deformation degree of the metal is small, uneven deformation is more likely to occur in adjacent grains, that is, the dislocation density differs, making the recrystallization mechanism of grain boundary bulging nucleation more likely to occur.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断一个陈述是否正确（Determine whether the following view is correct），并且答案直接给出了该陈述是错误的（Incorrect）以及解释原因。这符合判断题的特征，即对给定的陈述进行对错判断。 | 知识层次: 题目涉及金属变形与再结晶机制的关联分析，需要理解变形程度对晶界凸起形核机制的影响，并进行综合判断，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合分析金属变形程度与再结晶机制之间的关系。题目不仅要求理解晶界凸起成核机制的概念，还需要掌握变形程度对位错密度分布的影响，并能将这两个概念关联起来进行判断。正确选项的解释涉及多步推理过程，包括理解小变形时的不均匀变形特性及其对位错密度差异的影响，这超出了简单概念记忆的范畴，需要进行较深入的综合分析。", "convertible": true, "correct_option": "Incorrect. When the cold deformation degree of the metal is small, uneven deformation is more likely to occur in adjacent grains, that is, the dislocation density differs, making the recrystallization mechanism of grain boundary bulging nucleation more likely to occur.", "choice_question": "Determine whether the following view is correct. (8) The greater the deformation of the metal, the more likely the recrystallization mechanism of grain boundary bulging nucleation will occur.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The greater the deformation of the metal, the more likely the recrystallization mechanism of grain boundary bulging nucleation will occur.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "When the cold deformation degree of the metal is small, uneven deformation is more likely to occur in adjacent grains, that is, the dislocation density differs, making the recrystallization mechanism of grain boundary bulging nucleation more likely to occur. Greater deformation leads to more uniform dislocation distribution, reducing the likelihood of this specific nucleation mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1353, "question": "According to solidification theory, what is the fundamental principle of grain refinement by vibration and stirring?", "answer": "Vibration and stirring. Vibration and stirring can input additional energy into the liquid to provide nucleation work, promoting nucleation. On the other hand, they can cause crystallized crystals to fragment under the impact of liquid flow, increasing the number of nuclei.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释振动和搅拌细化晶粒的基本原理，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释振动和搅拌对晶粒细化的基本原理，涉及凝固理论中的成核和晶体破碎机制，需要综合运用多个概念并进行机理分析，思维深度较高。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅要理解凝固理论的基本概念，还需要综合运用知识分析振动和搅拌对晶粒细化的影响机理。正确选项涉及能量输入、形核功、晶体破碎等多个复杂过程的解释，需要考生具备深入的理论知识和综合分析能力。这种在选择题中要求全面分析复杂现象并解释深层机理的题目，属于选择题型中的最高难度层级。", "convertible": true, "correct_option": "Vibration and stirring can input additional energy into the liquid to provide nucleation work, promoting nucleation. On the other hand, they can cause crystallized crystals to fragment under the impact of liquid flow, increasing the number of nuclei.", "choice_question": "According to solidification theory, what is the fundamental principle of grain refinement by vibration and stirring?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Vibration and stirring increase nucleation by providing additional energy for nucleation work and fragmenting existing crystals", "B": "Vibration reduces surface tension while stirring increases undercooling, both promoting heterogeneous nucleation", "C": "Mechanical agitation disrupts solute diffusion layers, creating constitutional undercooling zones for nucleation", "D": "The primary mechanism is thermal homogenization which reduces local superheating and promotes uniform nucleation" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the dual mechanisms of energy input for nucleation work and crystal fragmentation. Option B incorrectly combines unrelated surface tension effects with undercooling. Option C describes a real phenomenon (constitutional undercooling) but misattributes it as the primary refinement mechanism. Option D sounds plausible by mentioning thermal effects but incorrectly identifies homogenization as the key factor rather than nucleation promotion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4061, "question": "[a] Aluminum alloys are generally viable as lightweight structural materials in humid environments because they are not very susceptible to corrosion by water vapor.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（Aluminum alloys are generally viable as lightweight structural materials in humid environments because they are not very susceptible to corrosion by water vapor.），并要求判断其正误（答案：T），符合判断题的特征。 | 知识层次: 题目考查对铝合金在潮湿环境中耐腐蚀性的基本概念记忆和理解，属于基础知识的直接应用。 | 难度: 在选择题型中，此题属于基本概念正误判断。题目直接考察对铝合金在潮湿环境中耐腐蚀性的基础概念记忆，只需判断陈述是否正确即可，无需深入理解或分析多个概念。", "convertible": true, "correct_option": "T", "choice_question": "[a] Aluminum alloys are generally viable as lightweight structural materials in humid environments because they are not very susceptible to corrosion by water vapor.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All aluminum alloys form a protective oxide layer that completely prevents corrosion in seawater environments.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most aluminum alloys do form a protective oxide layer, the statement is incorrect because: 1) The protection is not 'complete' - some corrosion can still occur, especially in aggressive environments like seawater; 2) Certain aluminum alloys (particularly those with high copper content) are more susceptible to corrosion; 3) The oxide layer can be compromised by factors like mechanical damage or chemical attack. The absolute wording ('completely prevents') makes this statement false despite the general truth about oxide layer formation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3716, "question": "A polymer bar's dimensions are 1 in . × 2 in. × 15 in. The polymer has a modulus of elasticity of 600,000 psi. What force is required to stretch the bar elastically to 15.25 in.?", "answer": "the force required is 200,000 lb.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解所需的力，答案是一个具体的数值结果（200,000 lb），符合计算题的特征。 | 知识层次: 题目涉及基本的弹性模量公式应用和简单计算，仅需直接套用公式并代入数值进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算弹性拉伸所需的力，直接应用胡克定律（F = kΔx）即可得出答案。解题步骤简单，仅需代入已知数值（弹性模量、尺寸变化）进行基本计算，无需复杂推导或多公式组合。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "200,000 lb", "choice_question": "A polymer bar's dimensions are 1 in. × 2 in. × 15 in. The polymer has a modulus of elasticity of 600,000 psi. What force is required to stretch the bar elastically to 15.25 in.?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format with the correct option being the calculated force.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "200,000 lb", "B": "100,000 lb", "C": "400,000 psi", "D": "300,000 N" }, "correct_answer": "A", "explanation": "正确答案A通过胡克定律计算得出：应变=(15.25-15)/15=0.0167，应力=600,000 psi × 0.0167=10,000 psi，力=10,000 psi × (1×2) in²=20,000 lb。干扰项B是正确答案的一半，利用常见计算错误；C使用正确数值但错误单位（psi而非lb），利用单位混淆；D使用国际单位但未正确转换，利用跨单位系统陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4084, "question": "As the porosity of refractory ceramic bricks increases, what happens to the chemical resistance?", "answer": "Chemical resistance decreases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释孔隙率增加对耐火陶瓷砖化学抗性的影响，答案需要文字解释和论述，而不是从选项中选择或简单判断对错。 | 知识层次: 题目考查对多孔耐火陶瓷砖化学抗性随孔隙率变化的基本概念的理解和记忆，属于基础概念层次。 | 难度: 在选择题型中，这道题目属于基本定义简答的难度等级。题目直接考察对\"孔隙率增加对耐火砖化学抵抗性影响\"这一基础概念的简单记忆，只需记住\"孔隙率增加会导致化学抵抗性下降\"这一基本原理即可作答，无需进行概念解释或复杂分析。", "convertible": true, "correct_option": "Chemical resistance decreases", "choice_question": "As the porosity of refractory ceramic bricks increases, what happens to the chemical resistance?", "conversion_reason": "The answer is a standard statement that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chemical resistance increases due to reduced surface area for chemical attack", "B": "Chemical resistance decreases as porosity provides pathways for corrosive agents", "C": "Chemical resistance remains unchanged as porosity only affects mechanical properties", "D": "Chemical resistance first increases then decreases due to competing surface area and diffusion effects" }, "correct_answer": "B", "explanation": "The correct answer is B because increased porosity creates more pathways for corrosive agents to penetrate the material, reducing chemical resistance. Option A is a cognitive bias trap, incorrectly applying surface area logic from catalysis. Option C exploits material property isolation fallacy. Option D creates a multi-parameter verification trap by introducing a non-existent threshold effect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1751, "question": "In the sintering process, the mass transfer method that only gradually increases the strength of the green body without causing shrinkage of the green body is a. lattice diffusion b. flow mass transfer c. evaporation-condensation d. dissolution-precipitation", "answer": "c", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项a、b、c、d中选择正确答案，符合选择题的特征 | 知识层次: 题目考查烧结过程中物质传递方式的基本概念记忆和理解，特别是蒸发-凝聚这一特定机制的特征，属于基础概念记忆范畴。 | 难度: 在选择题中属于中等偏下难度，需要理解烧结过程中不同传质方式的基本概念及其对生坯的影响，并进行简单辨析。虽然涉及多个概念，但题目明确给出了关键特征（不引起收缩），降低了分析复杂度。", "convertible": true, "correct_option": "c", "choice_question": "In the sintering process, the mass transfer method that only gradually increases the strength of the green body without causing shrinkage of the green body is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain boundary diffusion dominates when particle size is below 100nm", "B": "Surface diffusion becomes negligible above 800°C for most ceramics", "C": "Volume diffusion activation energy is always higher than grain boundary diffusion", "D": "Dislocation pipe diffusion is the primary mechanism in fully dense materials" }, "correct_answer": "C", "explanation": "Correct answer is C because volume diffusion requires breaking more atomic bonds than grain boundary diffusion. A is a trap exploiting the common misconception about size effects - while GB diffusion increases in importance at small sizes, it doesn't 'dominate'. B uses temperature intuition incorrectly - surface diffusion remains significant even at high T. D sounds plausible but dislocations are annihilated during densification.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4765, "question": "For some viscoelastic polymers that are subjected to stress relaxation tests, the stress decays with time according to\n\\[\n\\sigma(t)=\\sigma(0) \\exp \\left(-\\frac{t}{\\tau}\\right)\n\\]\nwhere \\sigma(t) and \\sigma(0) represent the time-dependent and initial (i.e., time =0 ) stresses, respectively, and t and \\tau denote elapsed time and the relaxation time, respectively; \\tau is a time-independent constant characteristic of the material. A specimen of a viscoelastic polymer whose stress relaxation obeys Equation was suddenly pulled in tension to a measured strain of 0.5 ; the stress necessary to maintain this constant strain was measured as a function of time. Determine E_{f}(10) for this material if the initial stress level was 3.5 MPa(500 psi), which dropped to 0.5 MPa(70 psi) after 30s.", "answer": "e_{f}(10) = 3.66 \\text{mpa} (522 \\text{psi})", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求根据给定的公式和初始条件进行数值计算，最终得出一个具体的数值结果（E_{f}(10) = 3.66 \\text{mpa}）。解答过程涉及公式应用和数值计算，符合计算题的特征。 | 知识层次: 题目需要应用给定的应力松弛公式进行多步计算，包括初始应力和松弛时间的确定，以及最终计算E_f(10)。虽然公式直接给出，但需要理解公式中各参数的含义，并进行适当的代数运算和数值计算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及应力松弛测试的基本概念、指数衰减公式的应用以及多步计算过程。虽然题目提供了公式和初始条件，但需要考生正确理解并应用这些信息进行综合计算，才能得出正确的弹性模量值。这要求考生具备一定的材料科学知识背景和计算能力。", "convertible": true, "correct_option": "3.66 MPa (522 psi)", "choice_question": "For some viscoelastic polymers that are subjected to stress relaxation tests, the stress decays with time according to \\(\\sigma(t)=\\sigma(0) \\exp \\left(-\\frac{t}{\\tau}\\right)\\), where \\(\\sigma(t)\\) and \\(\\sigma(0)\\) represent the time-dependent and initial (i.e., time =0 ) stresses, respectively, and \\(t\\) and \\(\\tau\\) denote elapsed time and the relaxation time, respectively; \\(\\tau\\) is a time-independent constant characteristic of the material. A specimen of a viscoelastic polymer whose stress relaxation obeys the equation was suddenly pulled in tension to a measured strain of 0.5; the stress necessary to maintain this constant strain was measured as a function of time. Determine \\(E_{f}(10)\\) for this material if the initial stress level was 3.5 MPa (500 psi), which dropped to 0.5 MPa (70 psi) after 30s. The correct value of \\(E_{f}(10)\\) is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.66 MPa (522 psi)", "B": "1.83 MPa (261 psi)", "C": "7.32 MPa (1044 psi)", "D": "0.61 MPa (87 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A (3.66 MPa) calculated using the stress relaxation equation with τ=30/ln7≈10.5s. Option B is half the correct value, exploiting the common error of dividing by 2 when calculating relaxation modulus. Option C doubles the correct value, targeting those who confuse stress with modulus scaling. Option D uses incorrect logarithmic scaling (1/6 of initial stress), appealing to those who misapply exponential decay principles.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2998, "question": "The three mechanical states corresponding to linear amorphous polymers are the usage states of (7), (8), and (9)", "answer": "(7) plastic; (8) rubber; (9) flow resin", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写三个机械状态的名称，需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查对线性无定形聚合物三种力学状态的基本概念记忆，属于定义和分类的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆线性无定形聚合物的三种力学状态对应的具体名称（塑料、橡胶、流动树脂），属于基础概念的直接回忆。无需解释或分析，解题步骤简单，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "plastic; rubber; flow resin", "choice_question": "The three mechanical states corresponding to linear amorphous polymers are the usage states of:", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "plastic; rubber; flow resin", "B": "glass; rubber; viscous liquid", "C": "crystalline; viscoelastic; molten", "D": "elastic; plastic; brittle" }, "correct_answer": "A", "explanation": "The correct answer is A because linear amorphous polymers exhibit three distinct mechanical states corresponding to different temperature ranges: plastic (glassy state below Tg), rubber (elastomeric state between Tg and Tm), and flow resin (viscous flow above Tm). Option B is a cognitive bias trap using technically correct polymer states but not the specific usage states. Option C exploits professional intuition by mixing crystalline states (invalid for amorphous polymers) with correct concepts. Option D is a multi-level verification trap presenting common mechanical properties that don't correspond to the specific usage states of amorphous polymers.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 737, "question": "In the non-stoichiometric compound $\\\\operatorname{Cd}_{1+x}0$, the lattice defect present is (a) anion vacancy (b) cation vacancy (c) anion interstitial (d) cation interstitial", "answer": "d", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项(a)到(d)中选择正确答案 | 知识层次: 题目考查对非化学计量化合物中晶格缺陷类型的基础概念记忆和理解，只需识别Cd1+xO中存在的缺陷类型即可，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及非化学计量化合物的晶格缺陷这一基础概念，但需要考生理解并区分不同类型的缺陷（如空位和间隙）。正确选项（d）要求考生能够识别出阳离子间隙的存在，这需要一定的概念理解和简单辨析能力，而不仅仅是直接记忆。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "d", "choice_question": "In the non-stoichiometric compound $\\operatorname{Cd}_{1+x}0$, the lattice defect present is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Frenkel defect dominates in NaCl at room temperature", "B": "Schottky defect formation energy decreases with increasing ionic radius", "C": "In TiO2, oxygen vacancies act as n-type dopants", "D": "Antisite defects are more common in intermetallics than in ionic crystals" }, "correct_answer": "C", "explanation": "Correct answer is C because oxygen vacancies in TiO2 donate electrons to the conduction band, creating n-type conductivity. A is incorrect because NaCl primarily shows Schottky defects at room temperature (Frenkel defects require similar cation/anion sizes). B is a trap - while larger ions reduce lattice energy, Schottky defect energy actually increases with ionic radius due to stronger Coulombic interactions. D is misleading - while true for intermetallics, the phrasing suggests a comparison that doesn't exist in the question context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 696, "question": "In the cubic crystal system, the possible types of space lattices are (a) P, I, C (b) P, I, F (c) P, C, F (d) F, I, C", "answer": "The unit cell is (1)", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项(a)-(d)中选择正确的空间点阵类型组合，符合选择题的特征 | 知识层次: 题目考查立方晶系中空间点阵类型的基本概念记忆，属于对晶体学基础知识的直接考察，无需复杂分析或计算。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别立方晶系中可能的空间格子类型。正确选项直接对应记忆性知识，无需复杂分析或理解多个概念。因此，在选择题型内属于简单难度。", "convertible": true, "correct_option": "b", "choice_question": "In the cubic crystal system, the possible types of space lattices are", "conversion_reason": "The original question is already in a multiple-choice format with distinct options (a, b, c, d). The answer provided indicates the correct option is (1), which corresponds to option (b) in the question. Therefore, it can be converted to a standard single-choice question format by extracting the correct option and presenting the question without the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship predicts increased yield strength with decreasing grain size in all polycrystalline materials", "B": "The Hall-Petch relationship applies only to BCC metals and breaks down for nanocrystalline materials", "C": "The Hall-Petch relationship shows a linear increase in hardness with grain size reduction, regardless of crystal structure", "D": "The Hall-Petch relationship becomes invalid when grain size exceeds 100 micrometers" }, "correct_answer": "B", "explanation": "The correct answer is B because the Hall-Petch relationship is known to break down at very small grain sizes (nanocrystalline regime) and was originally developed for BCC metals. Option A is incorrect because it falsely generalizes the relationship to all materials. Option C is a cognitive bias trap, incorrectly suggesting a universal linear relationship. Option D exploits numerical intuition by suggesting an arbitrary grain size limit that doesn't correspond to actual physical phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2266, "question": "Describe the characteristics of diffusionless phase transformation.", "answer": "Diffusionless phase transformation has the following characteristics: (1) There is a shape change caused by uniform shear, resulting in a change in the crystal's external form. (2) Since the phase transformation process is diffusionless, the new phase and the parent phase have the same chemical composition. (3) There is a certain crystallographic orientation relationship between the parent phase and the new phase. (4) The phase boundary moves extremely fast, approaching the speed of sound.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求描述扩散less相变的特征，答案以文字解释和论述的形式呈现，没有选项、判断或计算要求。 | 知识层次: 题目要求描述扩散相变的特征，涉及对相变过程中晶体结构变化、化学成分保持、取向关系以及相界移动速度的理解和综合分析。虽然不涉及复杂计算，但需要将多个概念关联起来进行解释，属于中等应用层次。 | 难度: 在选择题型内，该题目属于较高难度。题目要求考生不仅理解扩散型相变的基本概念，还需要掌握扩散型相变与无扩散型相变的区别，并能综合分析无扩散型相变的多个特征（如形状变化、化学成分不变、晶体学取向关系、相界移动速度等）。这些知识点需要考生进行多角度分析和关联性思考，而不仅仅是简单的记忆或单一概念的应用。因此，该题目在选择题型中属于等级4的难度。", "convertible": true, "correct_option": "Diffusionless phase transformation has the following characteristics: (1) There is a shape change caused by uniform shear, resulting in a change in the crystal's external form. (2) Since the phase transformation process is diffusionless, the new phase and the parent phase have the same chemical composition. (3) There is a certain crystallographic orientation relationship between the parent phase and the new phase. (4) The phase boundary moves extremely fast, approaching the speed of sound.", "choice_question": "Which of the following correctly describes the characteristics of diffusionless phase transformation?", "conversion_reason": "The answer is a standard description of the characteristics of diffusionless phase transformation, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The transformation occurs through coordinated atomic shuffles without long-range diffusion, preserving the parent phase composition", "B": "The process requires significant undercooling to overcome the activation energy barrier for diffusion", "C": "The new phase forms via nucleation and growth with composition gradients at the interface", "D": "The transformation rate is controlled by the diffusion coefficient of the slowest-moving species" }, "correct_answer": "A", "explanation": "Correct answer A describes the key feature of diffusionless transformations where atoms move cooperatively without composition change. Option B is a cognitive bias trap - while undercooling is needed, it's not for diffusion activation. Option C exploits nucleation/growth intuition but incorrectly introduces composition gradients. Option D uses diffusion-controlled transformation logic which doesn't apply to diffusionless processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4226, "question": "The metal iridium has an FCC crystal structure. If the angle of diffraction for the (220) set of planes occurs at 69.22 degrees (first-order reflection) when monochromatic x-radiation having a wavelength of 0.1542 nm is used, compute the interplanar spacing for this set of planes.", "answer": "the interplanar spacing for the (220) set of planes for iridium is 0.1357 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（布拉格定律）来求解晶面间距，答案是一个具体的数值结果（0.1357 nm），符合计算题的特征。 | 知识层次: 题目主要涉及布拉格定律的直接应用，通过给定的衍射角和波长计算晶面间距。虽然需要理解布拉格定律和晶面间距的概念，但计算过程相对直接，属于基本公式应用和简单计算范畴。 | 难度: 在选择题型中，该题目仅需要直接应用布拉格公式（nλ = 2d sinθ）进行一步计算即可得出答案。题目已经给出了所有必要的参数（衍射角、波长、反射级数），无需额外的推导或组合公式。因此，在选择题型内属于最简单的难度等级1。", "convertible": true, "correct_option": "0.1357 nm", "choice_question": "The metal iridium has an FCC crystal structure. If the angle of diffraction for the (220) set of planes occurs at 69.22 degrees (first-order reflection) when monochromatic x-radiation having a wavelength of 0.1542 nm is used, what is the interplanar spacing for this set of planes?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1357 nm", "B": "0.1542 nm", "C": "0.2694 nm", "D": "0.1085 nm" }, "correct_answer": "A", "explanation": "The correct answer is calculated using Bragg's Law: nλ = 2d sinθ. For first-order reflection (n=1), d = λ/(2 sinθ) = 0.1542 nm / (2 sin69.22°) = 0.1357 nm. Option B is the wavelength value itself, exploiting AI's potential confusion between input parameter and output result. Option C comes from incorrectly using θ instead of sinθ in the calculation (0.1542/(2*69.22°)). Option D is derived from an erroneous FCC structure factor calculation (d220=a/√8), where a is incorrectly taken as the wavelength.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1677, "question": "The methods for strengthening metal materials include (13) _ strengthening, (14) strengthening, (15) strengthening, _ (16) strengthening", "answer": "(13) solid solution; (14) dislocation; (15) fine grain; (16) dispersion (or precipitate particles)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写具体的强化方法名称，需要根据知识进行文字回答，而不是选择、判断或计算 | 知识层次: 题目主要考查对金属材料强化方法的基本概念的记忆和理解，包括固溶强化、位错强化、细晶强化和弥散强化等基础知识点，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确回忆并区分四种不同的金属强化方法（固溶强化、位错强化、细晶强化、弥散强化或沉淀强化）。这要求考生不仅记住定义，还要能正确分类和匹配每种强化方法的名称。相比等级1的简单定义回忆，该题目需要更深入的概念理解和分类能力，但尚未达到等级3的复杂概念体系阐述水平。", "convertible": true, "correct_option": "solid solution; dislocation; fine grain; dispersion (or precipitate particles)", "choice_question": "The methods for strengthening metal materials include:", "conversion_reason": "The original question is a fill-in-the-blank type with specific standard terms as answers. It can be converted into a multiple-choice question by listing the correct terms as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening", "B": "Elastic modulus enhancement", "C": "Surface hardening", "D": "Phase transformation toughening" }, "correct_answer": "A", "explanation": "Solid solution strengthening is a fundamental method for strengthening metals by introducing solute atoms into the crystal lattice. Option B exploits cognitive bias by using a related but incorrect concept (elastic modulus is an intrinsic property, not a strengthening mechanism). Option C is a surface treatment method rather than bulk strengthening. Option D is a valid concept but primarily applies to ceramics, creating a material system analogy trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1078, "question": "Calculate the relative content of each microstructural constituent in an alloy containing 0.40% C when it is cooled to room temperature under equilibrium conditions.", "answer": "The relative content of each microstructural constituent: w_P=(0.40-0.0218)/(0.77-0.0218)×100%=50.5%; w_a=1-w_P=1-50.5%=49.5%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定合金中各微观结构组成的相对含量，答案给出了具体的计算过程和结果。 | 知识层次: 题目要求应用杠杆定律进行简单的二元合金相组成计算，属于基本公式的直接套用和单步计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用杠杆定律公式进行相对含量的计算，但解题步骤明确且直接，仅涉及单一公式的套用和简单代数运算。不需要复杂的推导或多步骤分析，符合选择题型中等级2的难度标准。", "convertible": true, "correct_option": "w_P=50.5%; w_a=49.5%", "choice_question": "What is the relative content of each microstructural constituent in an alloy containing 0.40% C when it is cooled to room temperature under equilibrium conditions?", "conversion_reason": "The answer is a specific numerical result, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "w_P=50.5%; w_a=49.5%", "B": "w_P=49.5%; w_a=50.5%", "C": "w_P=72.4%; w_a=27.6%", "D": "w_P=27.6%; w_a=72.4%" }, "correct_answer": "A", "explanation": "正确答案A基于铁碳相图杠杆定律计算，在0.40% C合金中，室温下珠光体(w_P)和铁素体(w_a)的相对含量应分别为50.5%和49.5%。干扰项B通过数值反转制造认知偏差陷阱；干扰项C利用了常见错误记忆点(共析点0.77% C的珠光体含量)；干扰项D则基于对亚共析钢中相含量变化趋势的直觉误判。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4561, "question": "Why does chromium in stainless steels make them more corrosion resistant in many environments than plain carbon steels?", "answer": "The chromium in stainless steels causes a very thin and highly adherent surface coating to form over the surface of the alloy, which protects it from further corrosion. For plain carbon steels, rust, instead of this adherent coating, forms.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释铬在不锈钢中的作用机制，答案需要文字解释和论述，没有提供选项或要求计算。 | 知识层次: 题目要求解释铬在不锈钢中提高耐腐蚀性的机理，涉及表面涂层形成和保护作用的综合分析，需要理解合金元素的作用机制及其与腐蚀行为的关系，属于较深层次的机理解释和推理分析。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅理解铬在不锈钢中的作用，还需要掌握其具体机理（形成薄而紧密的表面涂层），并能与普通碳钢的腐蚀机制进行对比分析。这需要考生具备材料科学中腐蚀防护的深层机理知识，并能综合运用这些知识解释复杂现象。题目涉及的知识点掌握深度要求较高，解题时需要结合多个概念进行推理分析，因此属于选择题型中较难的题目。", "convertible": true, "correct_option": "The chromium in stainless steels causes a very thin and highly adherent surface coating to form over the surface of the alloy, which protects it from further corrosion. For plain carbon steels, rust, instead of this adherent coating, forms.", "choice_question": "Why does chromium in stainless steels make them more corrosion resistant in many environments than plain carbon steels?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chromium forms a passive oxide layer that is self-repairing in the presence of oxygen", "B": "Chromium increases the steel's hardness which physically blocks corrosive agents", "C": "Chromium reacts with carbon to form chromium carbides that prevent rust nucleation", "D": "Chromium lowers the steel's electrical conductivity, reducing galvanic corrosion" }, "correct_answer": "A", "explanation": "The correct answer is A because chromium forms a thin, adherent chromium oxide passive layer that protects the underlying steel and can self-repair when damaged. Option B is incorrect because while chromium does increase hardness, this is not the primary corrosion resistance mechanism. Option C is a partial truth trap - chromium carbides do form but can actually decrease corrosion resistance at grain boundaries. Option D exploits conductivity confusion - while conductivity affects galvanic corrosion, this is not the primary role of chromium in stainless steels.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 139, "question": "The viscosity of Pyrex glass is 10^9 Pa·s at 1400°C and 10^13 Pa·s at 840°C. To facilitate forming, approximately what temperature is required for the glass to reach a viscosity of 10^5 Pa·s?", "answer": "According to the formula: η = η0 exp(ΔE / (R T)). Given η0 = 11.22 Pa·s and ΔE = 254.62 kJ/mol. When η = 10^5 Pa·s, 10^5 = 11.22 exp(254.62 × 1000 / ((273 + t) × 8.314)). Solving gives t = 3094.2°C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过给定的公式和数据进行数值计算，以求解特定温度值。答案展示了详细的公式应用和计算过程，符合计算题的特征。 | 知识层次: 题目需要应用Arrhenius方程进行多步计算，涉及对数运算和温度转换，需要理解粘度与温度的关系并正确应用公式。虽然不涉及复杂的综合分析或机理解释，但计算过程较为复杂，超出了简单应用的范畴。 | 难度: 在选择题中属于高难度题目，需要理解粘度与温度的复杂关系，应用阿伦尼乌斯公式进行多步计算，涉及对数运算和温度转换，且需要处理较大的数值范围和单位换算。解题过程需要较强的综合分析能力和数学运算技巧，超出了选择题常见的简单计算或概念判断的范畴。", "convertible": true, "correct_option": "3094.2°C", "choice_question": "The viscosity of Pyrex glass is 10^9 Pa·s at 1400°C and 10^13 Pa·s at 840°C. To facilitate forming, approximately what temperature is required for the glass to reach a viscosity of 10^5 Pa·s?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3094.2°C", "B": "1680°C", "C": "2150°C", "D": "2750°C" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算玻璃粘度的Arrhenius方程得到的。干扰项B(1680°C)利用了常见玻璃加工温度的直觉陷阱；干扰项C(2150°C)是基于线性外推的错误假设；干扰项D(2750°C)看起来接近正确答案但忽略了粘度对温度的指数依赖关系。这些干扰项都利用了材料科学中常见的认知偏差和直觉错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1018, "question": "Analyze the effect of cold plastic deformation on the microstructure of alloys", "answer": "1) Microstructure: 1 Formation of fibrous structure, grains are elongated along the deformation direction; 2 Formation of dislocation cells; 3 Grain rotation forms deformation texture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析冷塑性变形对合金微观结构的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析冷塑性变形对合金微观结构的影响，涉及多个微观结构变化的解释（纤维结构形成、位错胞形成、变形织构形成），需要综合运用材料科学原理进行机理分析和推理，思维过程深度较高。 | 难度: 在选择题型中，该题目属于高难度等级。题目要求分析冷塑性变形对合金微观结构的影响，涉及多个复杂的知识点，包括纤维结构的形成、位错胞的形成以及变形织构的形成。这些知识点不仅需要深入理解，还需要综合运用和推理分析。此外，题目要求对复杂现象进行全面分析，这在选择题型中属于较高层次的能力要求。因此，该题目在选择题型内属于最高难度等级。", "convertible": true, "correct_option": "1) Microstructure: 1 Formation of fibrous structure, grains are elongated along the deformation direction; 2 Formation of dislocation cells; 3 Grain rotation forms deformation texture.", "choice_question": "Which of the following describes the effect of cold plastic deformation on the microstructure of alloys?", "conversion_reason": "The answer is a standard description of the effect of cold plastic deformation on the microstructure of alloys, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Formation of dislocation cells and elongated grains along deformation direction", "B": "Complete recrystallization with equiaxed grain formation", "C": "Significant grain growth due to deformation-induced heating", "D": "Formation of coherent twin boundaries throughout the microstructure" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual effects of cold working: dislocation multiplication forming cells and grain elongation. B is wrong because recrystallization requires annealing, not cold work. C exploits thermal intuition but cold working produces negligible heating. D uses a plausible concept (twinning) but coherent twins form during annealing, not cold deformation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3087, "question": "When designing fiber composites, for a matrix with good plasticity, how can the coefficient of expansion of carbon fiber be? A. Slightly lower B. Very different C. Slightly higher D. The same", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求从选项（A. Slightly lower B. Very different C. Slightly higher D. The same）中选择正确答案 | 知识层次: 题目要求在设计纤维复合材料时，考虑基体塑性和碳纤维膨胀系数的匹配关系，需要理解材料性能之间的相互作用并进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解复合材料设计中基体塑性与纤维膨胀系数的匹配关系，并进行概念关联分析。题目考察的是对材料性能协调性的综合判断能力，但不需要复杂的计算过程。", "convertible": true, "correct_option": "A. Slightly lower", "choice_question": "When designing fiber composites, for a matrix with good plasticity, how can the coefficient of expansion of carbon fiber be?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slightly lower", "B": "Very different", "C": "Slightly higher", "D": "The same" }, "correct_answer": "A", "explanation": "The correct answer is A because in fiber composites, the carbon fiber's coefficient of thermal expansion should be slightly lower than the matrix to ensure residual compressive stresses in the fiber, enhancing composite strength. Option B is a cognitive bias trap, as 'very different' seems plausible but would cause excessive interfacial stresses. Option C exploits intuition by suggesting higher expansion for plasticity accommodation, which is incorrect. Option D is a multi-level verification trap, as equal expansion seems ideal but prevents beneficial stress distribution.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3361, "question": "What are the ways to improve the strength of materials", "answer": "The strengthening effects of alloying elements in steel mainly include the following four methods: solid solution strengthening, grain boundary strengthening, second-phase strengthening, and dislocation strengthening. By applying these four methods individually or in combination, the strength of steel can be effectively improved.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述提高材料强度的多种方法，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释和论述提高材料强度的四种方法，涉及多个概念的关联和综合分析，需要理解不同强化机制的相互作用和应用场景，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅理解材料强化的基本概念（如固溶强化、晶界强化等），还需要综合掌握这些方法在钢铁材料中的具体应用和相互作用。正确选项涉及多个知识点的关联分析，且需要考生能够区分不同强化机制的特点和效果。这种综合分析能力在选择题型中属于多角度分析论述的层次，因此难度等级为4。", "convertible": true, "correct_option": "solid solution strengthening, grain boundary strengthening, second-phase strengthening, and dislocation strengthening", "choice_question": "Which of the following are the ways to improve the strength of materials?", "conversion_reason": "The answer provided is a standard set of methods for improving material strength, which can be formatted into a multiple-choice question with the correct options clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "solid solution strengthening", "B": "increasing the elastic modulus", "C": "reducing the dislocation density", "D": "increasing the thermal conductivity" }, "correct_answer": "A", "explanation": "Solid solution strengthening (A) is a correct method as solute atoms distort the crystal lattice and impede dislocation motion. Increasing elastic modulus (B) is incorrect as modulus is an intrinsic property. Reducing dislocation density (C) is incorrect as dislocations actually strengthen materials. Increasing thermal conductivity (D) is irrelevant to mechanical strength. Options B and C exploit the common confusion between intrinsic vs extrinsic properties, while D uses an unrelated material property.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 482, "question": "9.Linear polymers can be reused and are also called what kind of plastic; cross-linked polymers cannot be reused and are called what kind of plastic?", "answer": "Thermoplastic, thermosetting", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述两种塑料的名称，而不是从选项中选择或判断对错，也不需要数值计算。 | 知识层次: 题目考查对线性聚合物和交联聚合物的基本分类和名称的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆和识别线性聚合物和交联聚合物的基本分类名称（热塑性和热固性），属于基础概念记忆层次，解题步骤简单直接，无需深入理解或分析。", "convertible": true, "correct_option": "Thermoplastic, thermosetting", "choice_question": "Linear polymers can be reused and are also called what kind of plastic; cross-linked polymers cannot be reused and are called what kind of plastic?", "conversion_reason": "The answer is standard terminology and can be presented as a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermoplastic, thermosetting", "B": "Thermosetting, thermoplastic", "C": "Elastomer, thermoplastic", "D": "Thermoplastic, elastomer" }, "correct_answer": "A", "explanation": "The correct answer is A because linear polymers that can be reused are called thermoplastics, while cross-linked polymers that cannot be reused are called thermosetting plastics. Option B reverses the terms, exploiting a common reversal error. Option C introduces elastomers, which are a different class of materials, creating confusion with thermosets. Option D incorrectly pairs thermoplastics with elastomers, leveraging their shared reusability property while ignoring the cross-linking distinction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1711, "question": "How do dislocations affect the plastic deformation ability of metal materials?", "answer": "The plastic deformation of metals is achieved through the movement of dislocations, therefore the strengthening methods for metal materials can be realized by altering the number of dislocations in the material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释位错如何影响金属材料的塑性变形能力，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及位错对金属材料塑性变形能力的影响，需要理解位错运动与塑性变形的关系，并能够分析强化方法如何通过改变位错数量来实现。这需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解位错对金属塑性变形的影响机制，并关联强化方法如何通过改变位错数量实现。题目涉及多步概念关联和综合分析，但未达到多角度或深度关联性分析的要求。", "convertible": true, "correct_option": "The plastic deformation of metals is achieved through the movement of dislocations, therefore the strengthening methods for metal materials can be realized by altering the number of dislocations in the material.", "choice_question": "How do dislocations affect the plastic deformation ability of metal materials?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The original question can remain unchanged as it is already suitable for a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dislocations enable plastic deformation by their movement, and strengthening is achieved by impeding this movement through increased dislocation density", "B": "Dislocations reduce plastic deformation by creating stress concentrations that initiate brittle fracture at lower strains", "C": "Dislocations have no effect on plastic deformation as it is primarily governed by grain boundary sliding in metals", "D": "Dislocations increase elastic modulus which indirectly enhances plastic deformation capacity through stored elastic energy" }, "correct_answer": "A", "explanation": "Correct answer A properly describes the dual role of dislocations in enabling plasticity through movement while also providing strengthening mechanisms when their motion is impeded. Option B exploits confusion between ductile and brittle fracture mechanisms. Option C targets misunderstanding of dominant deformation mechanisms. Option D creates a false connection between elastic properties and plastic deformation capacity.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3985, "question": "During the recrystallization of a cold-worked material, are grains with high strains replaced with new, unstrained grains?", "answer": "Grains with high strains are replaced with new, unstrained grains.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（对错），答案直接给出了判断结果（陈述是正确的）。这符合判断题的特征。 | 知识层次: 题目考查对再结晶过程中晶粒变化的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于基础概念正误判断，仅需记忆再结晶过程中高应变晶粒被新无应变晶粒替代的基本原理，无需深入理解或分析复杂概念。", "convertible": true, "correct_option": "Grains with high strains are replaced with new, unstrained grains.", "choice_question": "During the recrystallization of a cold-worked material, are grains with high strains replaced with new, unstrained grains?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All cold-worked materials will completely recrystallize when heated above 0.5Tm, forming entirely new strain-free grains.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While recrystallization generally occurs above 0.5Tm, the completeness depends on several factors including prior deformation level, heating rate, and material purity. Some materials may retain deformed grains or only partially recrystallize. The statement's use of 'all' and 'completely' makes it incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 423, "question": "3. The factors influencing the formation of substitutional solid solutions include _ (9)", "answer": "Electron concentration factor", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写影响置换固溶体形成的因素，需要提供具体的文字答案（电子浓度因素），而不是从多个选项中选择或进行判断或计算。 | 知识层次: 题目考查对置换固溶体形成影响因素的基础概念记忆，属于基本原理的记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆基础概念中的影响因素之一（电子浓度因素），属于直接回忆定义或分类的基本记忆性知识，无需解释或复杂分析，因此属于最低难度等级。", "convertible": true, "correct_option": "Electron concentration factor", "choice_question": "Which of the following factors influences the formation of substitutional solid solutions?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Electron concentration factor", "B": "Crystal structure compatibility", "C": "Atomic radius difference <15%", "D": "Thermal expansion coefficient matching" }, "correct_answer": "A", "explanation": "The electron concentration factor (Hume-Rothery rules) is the primary determinant for substitutional solid solution formation. Option B exploits cognitive bias by suggesting a seemingly logical but secondary factor. Option C is a classic intuitive trap using a correct but insufficient condition (radius difference alone doesn't guarantee solubility). Option D employs a multi-level verification trap by introducing a real material property that's irrelevant to solubility criteria.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3594, "question": "A metal having a cubic structure has a density of 1.892g / {cm}^{3}, an atomic weight \\mathrm{of} 132.91g / mol, and a lattice parameter of € 1.13 Å. One atom is associated with each lattice point. Determine the crystal structure of the \\mathrm{metal}.", "answer": "bcc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过计算和分析确定金属的晶体结构，需要文字解释和论述，而不仅仅是选择或判断。虽然答案简短（bcc），但解答过程涉及密度、原子量和晶格参数的计算和推理。 | 知识层次: 题目需要应用密度、原子质量和晶格参数的知识，通过多步计算来确定晶体的结构。这涉及到对立方晶体结构的理解以及相关公式的应用，属于中等难度的应用题目。 | 难度: 在选择题型中，这道题目属于较高难度。首先，题目要求考生掌握晶体结构、密度计算、原子量和晶格参数等多个概念。其次，解题过程涉及多步计算，包括计算单位晶胞中的原子数、验证计算结果与不同晶体结构（如bcc、fcc等）的匹配性。此外，题目还要求考生能够综合分析计算结果与晶体结构之间的关系，而不仅仅是简单的记忆或单一概念的应用。因此，这道题目在选择题型内属于多角度分析论述的难度等级。", "convertible": true, "correct_option": "bcc", "choice_question": "A metal having a cubic structure has a density of 1.892g/cm³, an atomic weight of 132.91g/mol, and a lattice parameter of 1.13 Å. One atom is associated with each lattice point. Determine the crystal structure of the metal from the following options:", "conversion_reason": "The answer is a standard term (bcc) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "fcc", "B": "bcc", "C": "sc", "D": "hcp" }, "correct_answer": "B", "explanation": "The correct answer is bcc because the calculated number of atoms per unit cell (1.88) is closest to 2, which is characteristic of a bcc structure. The fcc option (A) is a strong distractor as it's the most common cubic structure, exploiting the AI's statistical bias. Option C (sc) is numerically plausible but too simple for most metals. Option D (hcp) is invalid here but included to test if the AI notices the cubic constraint in the question.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3148, "question": "The lattice constant of a copper crystal is $a=0.362\\mathrm{nm},$ the density is $\\rho=8.98~\\mathrm{g/cm}^{3},$ and the relative atomic mass is 63.55. Determine the crystal structure of copper.", "answer": "From the physical meaning of density $\\rho=\\frac{6.023\\times10^{23}}{(0.362\\times10^{-7})^{3}}=8.98(g/\\mathrm{cm}^{3})$ n. Solving gives $n=3.997{\\approx}4.$ A cubic unit cell with 4 atoms corresponds to a face-centered cubic structure.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要通过数值计算和公式应用来确定铜的晶体结构，答案中给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，通过已知的晶格常数、密度和相对原子质量，直接套用密度公式进行计算，得出晶胞中的原子数，从而判断晶体结构。整个过程不需要多步计算或综合分析，属于直接应用基本知识的范畴。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解密度的物理意义并进行简单的代数运算，但整体步骤较为直接，仅涉及单一公式的套用和简单计算。与选择题型内其他更复杂的题目相比，该题的解题步骤和知识点掌握深度要求较低，因此属于等级2难度。", "convertible": true, "correct_option": "face-centered cubic structure", "choice_question": "The lattice constant of a copper crystal is $a=0.362\\mathrm{nm},$ the density is $\\rho=8.98~\\mathrm{g/cm}^{3},$ and the relative atomic mass is 63.55. Determine the crystal structure of copper from the following options:", "conversion_reason": "The answer is a standard term (face-centered cubic structure), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "face-centered cubic structure", "B": "body-centered cubic structure", "C": "hexagonal close-packed structure", "D": "diamond cubic structure" }, "correct_answer": "A", "explanation": "The correct answer is face-centered cubic (FCC) structure because the calculated number of atoms per unit cell (4) matches FCC. Option B is a cognitive bias trap - BCC is common for some metals but gives wrong atom count (2). Option C exploits HCP's similar packing factor but different symmetry. Option D uses a structure that would require much lower density for copper.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4532, "question": "For a continuous and oriented fiber-reinforced composite, the modulus of elasticity in the longitudinal direction is 19.7 GPa (2.8 x 10^5 psi). If the volume fraction of fibers is 0.25, determine the modulus of elasticity of the fiber phase.", "answer": "the modulus of elasticity of the fiber phase e_f is 70.4 GPa (10.2 x 10^6 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的参数（纵向弹性模量和纤维体积分数）应用复合材料力学公式计算纤维相的弹性模量，答案以具体数值形式给出，属于典型的计算题类型。 | 知识层次: 题目需要应用复合材料弹性模量的混合法则公式进行计算，涉及多步推导和概念关联（纤维和基体的弹性模量关系），但不需要复杂的综合分析或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解复合材料弹性模量的混合规则（Rule of Mixtures）概念，并能够正确应用公式进行多步计算。题目要求根据已知的复合材料纵向弹性模量和纤维体积分数，反推出纤维相的弹性模量，这涉及公式变形和单位换算（GPa与psi的转换），属于综合性计算问题。虽然题目给出了正确选项，但解题过程需要较强的概念关联能力和计算准确性。", "convertible": true, "correct_option": "70.4 GPa (10.2 x 10^6 psi)", "choice_question": "For a continuous and oriented fiber-reinforced composite, the modulus of elasticity in the longitudinal direction is 19.7 GPa (2.8 x 10^5 psi). If the volume fraction of fibers is 0.25, what is the modulus of elasticity of the fiber phase?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "70.4 GPa (10.2 x 10^6 psi)", "B": "78.8 GPa (11.4 x 10^6 psi)", "C": "19.7 GPa (2.8 x 10^5 psi)", "D": "52.8 GPa (7.6 x 10^6 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the rule of mixtures for continuous fiber composites (Ec = EfVf + EmVm). Option B is a cognitive bias trap that simply multiplies the composite modulus by 4 (1/Vf). Option C exploits the common mistake of confusing composite modulus with fiber modulus. Option D is a multi-level verification trap that correctly calculates the matrix contribution but incorrectly inverts the volume fractions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2800, "question": "Indicate approximately in which temperature range grain boundary diffusion dominates.", "answer": "In the low-temperature region (when 1/T is large), the lnD value of grain boundary diffusion is higher than that of bulk diffusion, and grain boundary diffusion dominates at this time. As the temperature increases (1/T decreases), the two curves will intersect, and in the high-temperature region above the intersection point, bulk diffusion will dominate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释在哪个温度范围内晶界扩散占主导地位，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求解释晶界扩散在特定温度范围内占主导的原因，涉及对扩散机制的理解和温度对扩散行为的影响分析。需要将晶界扩散和体扩散的概念关联起来，并通过温度变化对扩散系数的影响进行综合分析。虽然不涉及复杂计算，但需要一定的概念关联和推理分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握晶界扩散和体扩散的基本概念，并能分析温度变化对两种扩散机制的影响。虽然不需要复杂的计算，但需要对扩散机制在不同温度区间的相对优势进行综合判断，涉及概念关联和综合分析能力。", "convertible": true, "correct_option": "In the low-temperature region", "choice_question": "In which temperature range does grain boundary diffusion dominate?", "conversion_reason": "The answer is a standard concept that can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Below 0.3Tm (where Tm is absolute melting temperature)", "B": "Between 0.3-0.5Tm", "C": "Above 0.5Tm", "D": "Only at cryogenic temperatures (<100K)" }, "correct_answer": "A", "explanation": "Grain boundary diffusion dominates at low temperatures (below 0.3Tm) because the activation energy for grain boundary diffusion is lower than for lattice diffusion. Option B is a cognitive bias trap - it's the range where both mechanisms are active but doesn't represent dominance. Option C exploits the common misconception that higher temperatures always enhance diffusion. Option D is a professional intuition trap - while grain boundaries are important at cryogenic temps, the question asks about the temperature range of dominance, not absolute importance.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4174, "question": "Relative to electrons and electron states, what does the mj quantum number specify?", "answer": "The mj quantum number designates the number of electron states in each electron subshell.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对量子数mj的含义进行文字解释和论述，答案提供了详细的描述而非选择或判断。 | 知识层次: 题目考查对量子数mj的基本定义和作用的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆和理解mj量子数的基本定义，属于基础概念记忆层次。题目直接询问mj量子数的指定内容，正确选项也直接给出了定义，无需复杂的分析或推理步骤。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "The mj quantum number designates the number of electron states in each electron subshell.", "choice_question": "Relative to electrons and electron states, what does the mj quantum number specify?", "conversion_reason": "The answer is a standard concept in quantum mechanics, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The projection of total angular momentum along the quantization axis", "B": "The number of electron states in each electron subshell", "C": "The magnetic moment orientation relative to crystal lattice", "D": "The spin-orbit coupling strength of the electron" }, "correct_answer": "A", "explanation": "The mj quantum number specifically describes the projection of the total angular momentum (orbital + spin) along the quantization axis. Option B is a common misconception confusing mj with ml (magnetic quantum number). Option C exploits confusion between quantum numbers and macroscopic magnetic properties. Option D targets those who might associate 'j' with spin-orbit coupling but miss the precise definition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2679, "question": "MgO has a NaCl-type structure. The ionic radius of Mg2+ is 0.078nm, and the ionic radius of O2- is 0.132nm. Calculate the density (ρ) of MgO.", "answer": "ρ = 4[Ar(Mg) + Ar(O)] / (2rMg + 2rO)^3 × NA = 4 × 24.31 + 4 × 16.00 / 8 × (0.78 + 1.32)^3 × 10^-24 × 6.023 × 10^23 = 3.613 g/cm^3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的离子半径和晶体结构信息，应用公式进行密度计算，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要多步计算和概念关联，包括晶体结构类型的识别、离子半径的应用、密度计算公式的正确运用以及单位换算等综合分析过程。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、离子半径、密度计算等多个概念，并进行多步计算和单位换算。虽然题目提供了公式和部分计算过程，但仍需要考生具备综合分析能力和对相关物理化学知识的掌握。", "convertible": true, "correct_option": "3.613 g/cm^3", "choice_question": "MgO has a NaCl-type structure. The ionic radius of Mg2+ is 0.078nm, and the ionic radius of O2- is 0.132nm. The density (ρ) of MgO is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.613 g/cm³", "B": "4.326 g/cm³", "C": "2.891 g/cm³", "D": "5.217 g/cm³" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算得到的：首先计算晶格常数a=2(r_Mg2+ + r_O2-)=0.420nm，然后计算单位晶胞体积V=a³=7.4088×10⁻²³cm³，单位晶胞含有4个MgO分子，摩尔质量为40.3044g/mol，因此密度ρ=(4×40.3044)/(6.022×10²³×7.4088×10⁻²³)=3.613g/cm³。干扰项B通过错误使用离子半径比计算得出，利用了认知偏差；干扰项C假设了错误的配位数，属于专业直觉陷阱；干扰项D则错误地使用了简单相加法计算体积，是多层次验证陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3885, "question": "Which class of material is generally associated with the highest density values at room temperature? (a) Composites (b) Ceramics (c) Metals (d) Polymers", "answer": "(c) Metals", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从四个选项中选择正确答案，且答案形式为单一选项 | 知识层次: 题目考查对不同材料类别基本特性的记忆和理解，属于基础概念层次 | 难度: 该题目属于基础概念记忆类型，仅需识别不同材料类别的密度特性，无需复杂辨析或深度理解。在选择题型中，直接记忆金属通常具有最高密度即可作答，属于最简单的难度等级。", "convertible": true, "correct_option": "Metals", "choice_question": "Which class of material is generally associated with the highest density values at room temperature?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High-entropy alloys with FCC crystal structure", "B": "Tungsten-based heavy alloys", "C": "Osmium-iridium intermetallic compounds", "D": "Bulk metallic glasses containing platinum group metals" }, "correct_answer": "C", "explanation": "Osmium-iridium intermetallic compounds are the correct answer because they represent the densest known materials at room temperature, with osmium being the densest elemental metal (22.59 g/cm³) and iridium closely following (22.56 g/cm³). Their intermetallic compounds maintain these extreme densities. The other options are high-density materials but not the absolute highest: A) FCC high-entropy alloys typically have densities below 15 g/cm³ due to mixing of lighter elements; B) Tungsten alloys are dense (~19 g/cm³) but still below osmium/iridium; D) Metallic glasses have high densities but are limited by their amorphous structure and typically contain lighter elements that reduce overall density.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4763, "question": "The flexural strength and associated volume fraction porosity for two specimens of the same ceramic material are as follows: \begin{tabular}{ll} \\hline (\\sigma_{f_{S}}(\\mathbf{M P a})) & (\boldsymbol{P}) \\ \\hline 70 & 0.10 \\ 60 & 0.15 \\ \\hline \\end{tabular} (a) Compute the flexural strength for a completely nonporous specimen of this material.", "answer": "the flexural strength for a completely nonporous specimen of this material is 95.3 mpa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的数据计算非多孔试样的弯曲强度，需要使用公式进行数值计算，答案是一个具体的数值结果。 | 知识层次: 题目需要应用公式进行多步计算，涉及孔隙率与弯曲强度之间的关系，需要理解并应用相关公式来推导无孔隙材料的弯曲强度。这超出了简单应用的范围，但不需要复杂的分析或综合能力。 | 难度: 在选择题中属于中等偏上难度，需要理解陶瓷材料弯曲强度与孔隙率之间的关系，并能够运用给定的数据进行多步计算（如建立方程、求解未知数等）。虽然题目提供了部分数据，但解题过程涉及概念关联和综合分析，要求考生具备一定的材料科学基础知识和计算能力。", "convertible": true, "correct_option": "95.3 MPa", "choice_question": "The flexural strength and associated volume fraction porosity for two specimens of the same ceramic material are as follows: \n\n| σ_f (MPa) | P |\n|-----------|---|\n| 70 | 0.10 |\n| 60 | 0.15 |\n\nCompute the flexural strength for a completely nonporous specimen of this material:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "95.3 MPa", "B": "82.6 MPa", "C": "110.4 MPa", "D": "77.9 MPa" }, "correct_answer": "A", "explanation": "正确答案A通过孔隙率与强度的指数关系σ_f = σ_0 * exp(-nP)计算得出，其中σ_0为无孔隙强度。干扰项B采用线性外推法计算，忽略了陶瓷材料孔隙影响的非线性特性。干扰项C错误地使用了金属材料的孔隙修正系数。干扰项D是仅用第一个数据点计算的结果，未考虑数据一致性验证。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4345, "question": "Is it possible to have an iron-carbon alloy for which the mass fractions of total cementite and pearlite are 0.039 and 0.417 , respectively? Why or why not?", "answer": "no, such an iron-carbon alloy is not possible because the required carbon compositions for the given mass fractions of total cementite (0.28 wt% C) and pearlite (0.33 wt% C) are different.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么某种铁碳合金不可能存在，需要文字论述和解释，而不是简单的选择、判断或计算。答案也提供了详细的解释说明。 | 知识层次: 题目需要应用铁碳合金相图的知识，通过给定的质量分数计算碳含量，并进行比较分析。这涉及多步计算和概念关联，属于中等应用层次。 | 难度: 在选择题型中，该题目需要考生进行多步计算和概念关联，综合分析铁碳合金中碳含量与不同相（渗碳体和珠光体）质量分数之间的关系。题目不仅要求理解相图的基本概念，还需要能够应用杠杆定律进行具体计算，并比较不同相所需的碳含量是否一致。这种综合分析能力在选择题中属于较高难度，因此评为等级4。", "convertible": true, "correct_option": "no, such an iron-carbon alloy is not possible because the required carbon compositions for the given mass fractions of total cementite (0.28 wt% C) and pearlite (0.33 wt% C) are different.", "choice_question": "Is it possible to have an iron-carbon alloy for which the mass fractions of total cementite and pearlite are 0.039 and 0.417, respectively?", "conversion_reason": "The answer is a definitive statement that can be presented as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice structure by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because the carbon content required for 0.039 cementite (0.28 wt%) is within the range that can form 0.417 pearlite", "B": "Yes, because cementite and pearlite can coexist at any composition in the iron-carbon system", "C": "No, because the required carbon compositions for these mass fractions (0.28 wt% C for cementite and 0.33 wt% C for pearlite) are different", "D": "No, because pearlite cannot form at compositions below 0.76 wt% carbon" }, "correct_answer": "C", "explanation": "The correct answer is C because the calculation shows the required carbon compositions for the given mass fractions are different (0.28 wt% C for cementite vs 0.33 wt% C for pearlite), making this alloy impossible. Option A is a cognitive bias trap using plausible but incorrect range matching. Option B exploits common system knowledge overgeneralization. Option D is a professional intuition trap using correct pearlite formation knowledge but applying it incorrectly to this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4537, "question": "For a polymer-matrix fiber-reinforced composite, compare the desired mechanical characteristics of matrix and fiber phases.", "answer": "The matrix phase must be ductile and is usually relatively soft, whereas the fiber phase must be stiff and strong.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较和描述聚合物基纤维增强复合材料中基体和纤维相的机械特性，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对聚合物基纤维增强复合材料中基体和纤维相所需机械性能的基本概念记忆和理解，属于基础知识的直接应用，不需要复杂的分析或综合。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解和比较两种不同相（matrix和fiber）的机械特性，而不仅仅是简单的定义回忆。正确选项要求考生能够区分和描述matrix和fiber的机械特性，这比单纯记忆定义稍微复杂一些，但不需要复杂的分析或推理步骤。因此，难度等级为2。", "convertible": true, "correct_option": "The matrix phase must be ductile and is usually relatively soft, whereas the fiber phase must be stiff and strong.", "choice_question": "For a polymer-matrix fiber-reinforced composite, which of the following correctly compares the desired mechanical characteristics of matrix and fiber phases?", "conversion_reason": "The answer is a standard comparison of mechanical characteristics, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The matrix phase must be ductile and is usually relatively soft, whereas the fiber phase must be stiff and strong.", "B": "Both phases must exhibit high stiffness, but the matrix should have higher fracture toughness than the fibers.", "C": "The fiber phase should have lower elastic modulus than the matrix to ensure proper stress transfer.", "D": "Matrix and fiber phases should have nearly identical thermal expansion coefficients to prevent interfacial failure." }, "correct_answer": "A", "explanation": "Correct answer A states the fundamental requirement where the soft/ductile matrix protects brittle fibers while the stiff/strong fibers carry load. Option B is a cognitive bias trap - while toughness is important, matrix cannot be stiffer than fibers. Option C reverses the modulus relationship, exploiting common confusion about stress transfer mechanics. Option D uses a real concern (thermal mismatch) but incorrectly presumes identical coefficients are desirable, which would actually prevent beneficial residual stresses.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1534, "question": "What is uphill diffusion?", "answer": "Uphill diffusion refers to the process where substances diffuse from regions of low concentration to regions of high concentration, resulting in an increased concentration gradient. Examples include the copper-rich clusters formed in the early stages of aging in aluminum-copper alloys and the solute-enriched regions formed during spinodal decomposition in certain alloy solid solutions. The true driving force for uphill diffusion is the chemical potential gradient, not the concentration gradient. Although diffusion leads to an increase in the concentration gradient, the chemical potential gradient actually decreases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对\"uphill diffusion\"进行文字解释和论述，答案提供了详细的定义、示例和原理说明，符合简答题的特征。 | 知识层次: 题目不仅要求解释uphill diffusion的定义，还需要论述其驱动机制（化学势梯度而非浓度梯度）和实际例子（铝铜合金时效早期和调幅分解），涉及多个概念的关联和综合分析，思维深度较高。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Uphill diffusion refers to the process where substances diffuse from regions of low concentration to regions of high concentration, resulting in an increased concentration gradient. Examples include the copper-rich clusters formed in the early stages of aging in aluminum-copper alloys and the solute-enriched regions formed during spinodal decomposition in certain alloy solid solutions. The true driving force for uphill diffusion is the chemical potential gradient, not the concentration gradient. Although diffusion leads to an increase in the concentration gradient, the chemical potential gradient actually decreases.", "choice_question": "Which of the following best describes uphill diffusion?", "conversion_reason": "The answer is a standard definition and explanation of a scientific concept, which can be presented as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diffusion against the concentration gradient driven by chemical potential gradient, observed in spinodal decomposition", "B": "Enhanced diffusion along grain boundaries due to excess free energy", "C": "Anomalous fast diffusion in amorphous materials due to structural disorder", "D": "Temperature-dependent diffusion reversal in intermetallic compounds" }, "correct_answer": "A", "explanation": "Correct answer A describes the true nature of uphill diffusion where chemical potential gradient overrides concentration gradient. Option B exploits confusion with grain boundary diffusion which is faster but still follows concentration gradient. Option C targets misconceptions about disorder-enhanced diffusion. Option D creates a temperature-dependent reversal trap that sounds plausible but doesn't describe uphill diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3654, "question": "Tin atoms are introduced into a FCC copper crystal, producing an alloy with a lattice parameter of 3.7589 × 10^{-8} cm and a density of 8.772g / {cm}^{3}. Calculate the atomic percentage of tin present in the alloy.", "answer": "11.95%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解锡在合金中的原子百分比，答案是一个具体的数值结果（11.95%），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括利用晶格参数计算晶胞体积、应用密度公式计算原子质量、结合铜和锡的原子质量计算原子百分比等步骤。这需要综合运用材料科学中的晶体结构知识和化学计量知识，属于中等应用层次。 | 难度: 在选择题中属于高难度，需要综合运用多个概念（如晶体结构、密度计算、原子百分比等）并进行多步复杂计算。题目要求考生不仅掌握FCC晶格参数与密度的关系，还需要处理合金中不同原子的贡献，涉及单位换算和代数运算。这种综合性计算问题在选择题中属于较难的类型，需要较强的分析能力和计算技巧。", "convertible": true, "correct_option": "11.95%", "choice_question": "Tin atoms are introduced into a FCC copper crystal, producing an alloy with a lattice parameter of 3.7589 × 10^{-8} cm and a density of 8.772g / {cm}^{3}. What is the atomic percentage of tin present in the alloy?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "11.95%", "B": "9.87%", "C": "13.42%", "D": "7.56%" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算得出的。首先计算单位晶胞的质量和体积，然后根据密度确定单位晶胞中的原子数。铜的FCC结构每个晶胞有4个原子位置，通过比较计算得出的平均原子质量与纯铜的差异，可以确定锡的原子百分比。干扰项B利用了常见的计算误差，即忽略密度与晶格参数的精确关系；C选项基于过度估计锡的置换效应；D选项则错误地假设了更低的置换率，忽略了密度增加的影响。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2915, "question": "An Al-Cu alloy with an atomic fraction of 2% Cu is rapidly cooled from 520°C to 27°C and held for 3 hours, forming G.P. zones with an average spacing of 1.5×10^-6 cm. Given that the diffusion coefficient of Cu in Al at 27°C is D=2.3×10^-25 cm²/s, and assuming the process is diffusion-controlled, estimate the quenched vacancy concentration of the alloy.", "answer": "According to the vacancy concentration formula Cv=C0 exp(-Qv/RT), given the vacancy formation energy Qv=82.811 kJ/mol, temperature T=793 K, and R=8.314 J/(mol·K), the quenched vacancy concentration is Cv=2.3 exp(-82811/(8.314×793))=8.069×10^-6.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和数据进行数值计算，最终得出一个具体的数值结果（quenched vacancy concentration）。解答过程涉及公式应用和数值代入，符合计算题的特征。 | 知识层次: 题目需要应用扩散系数和空位浓度公式进行多步计算，涉及对扩散控制和空位形成能的理解，需要综合分析实验条件和计算结果。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及多步计算和概念关联，包括扩散系数、空位浓度公式、温度转换等。虽然给出了正确选项，但解题过程需要综合运用材料科学和热力学知识，进行较为复杂的计算和单位转换。", "convertible": true, "correct_option": "8.069×10^-6", "choice_question": "An Al-Cu alloy with an atomic fraction of 2% Cu is rapidly cooled from 520°C to 27°C and held for 3 hours, forming G.P. zones with an average spacing of 1.5×10^-6 cm. Given that the diffusion coefficient of Cu in Al at 27°C is D=2.3×10^-25 cm²/s, and assuming the process is diffusion-controlled, estimate the quenched vacancy concentration of the alloy.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.069×10^-6", "B": "4.035×10^-6", "C": "1.613×10^-5", "D": "2.3×10^-25" }, "correct_answer": "A", "explanation": "The correct answer is A (8.069×10^-6) because it is derived from the proper calculation of vacancy concentration using the given diffusion coefficient and G.P. zone spacing. Option B (4.035×10^-6) is a common error where the solver forgets to square the spacing term in the diffusion equation. Option C (1.613×10^-5) results from incorrectly doubling the correct value, a mistake that occurs when misinterpreting the relationship between vacancy concentration and diffusion. Option D (2.3×10^-25) is a direct trap using the diffusion coefficient value itself, exploiting the tendency to select given numbers without proper context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 919, "question": "3. Congruent solidification and incongruent solidification", "answer": "Solidification without compositional change is called congruent solidification; conversely, solidification accompanied by compositional change is called incongruent solidification.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对两个专业术语进行解释和区分，需要文字论述而非选择、判断或计算 | 知识层次: 题目考查的是对\"congruent solidification\"和\"incongruent solidification\"这两个基本概念的定义记忆和理解，属于材料科学中相变基础知识的范畴，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅涉及基础概念的定义记忆，无需复杂分析或比较。正确选项直接给出了\"congruent solidification\"和\"incongruent solidification\"的明确定义，属于最基础的定义简答类型。学生只需识别并匹配这两个术语与其定义即可，不需要进行任何推理或应用。", "convertible": true, "correct_option": "Solidification without compositional change is called congruent solidification; conversely, solidification accompanied by compositional change is called incongruent solidification.", "choice_question": "Which of the following correctly describes congruent and incongruent solidification?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect definitions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solidification without compositional change is called congruent solidification; conversely, solidification accompanied by compositional change is called incongruent solidification", "B": "Congruent solidification occurs when the solid phase has the same composition as the liquid phase, while incongruent solidification involves peritectic reactions", "C": "Congruent solidification refers to isomorphous systems where the solid and liquid compositions are identical, whereas incongruent solidification occurs in eutectic systems", "D": "Congruent solidification describes polymorphic transformations during cooling, while incongruent solidification refers to precipitation reactions" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines congruent solidification as occurring without compositional change and incongruent with change. Option B introduces a misleading focus on peritectic reactions which are just one type of incongruent solidification. Option C incorrectly limits congruent solidification to isomorphous systems and incongruent to eutectics. Option D completely misrepresents the concepts by confusing them with polymorphic transformations and precipitation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2083, "question": "At 800°C, which phases exist in Fe-0.002C steel?", "answer": "α phase, γ phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答在特定温度下存在的相，答案需要列举具体的相（α phase, γ phase），属于简答形式，不需要计算或选择。 | 知识层次: 题目考查对铁碳相图的基本记忆和理解，需要知道在800°C时Fe-0.002C钢中存在哪些相，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别Fe-0.002C钢在800°C时存在的相（α相和γ相），属于基础概念记忆层次。题目不涉及复杂的概念解释或比较分析，仅需直接回忆教材或课程中的基本知识点即可作答，因此在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "α phase, γ phase", "choice_question": "At 800°C, which of the following phases exist in Fe-0.002C steel?", "conversion_reason": "The answer is a standard terminology and can be converted into a multiple-choice format by listing possible phases as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "α phase only", "B": "γ phase only", "C": "α + γ phases", "D": "δ + γ phases" }, "correct_answer": "C", "explanation": "At 800°C and 0.002 wt% C, the Fe-C phase diagram shows both α (ferrite) and γ (austenite) phases coexist. Option A is incorrect because it ignores the γ phase stability at this temperature. Option B is wrong as it neglects the α phase that exists at this low carbon content. Option D introduces the δ phase which only exists at much higher temperatures (>1394°C), exploiting the common confusion between similar-looking phase regions. The correct answer requires precise interpretation of the Fe-C phase diagram at ultra-low carbon concentrations where both α and γ phases can coexist.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3569, "question": "The relationship between the probability of annealing twin formation and the stacking fault energy of a crystal is ( ). \\n\\nA. Unrelated, only depends on annealing temperature and time\\nB. Crystals with low stacking fault energy have a higher probability of forming annealing twins\\nC. Crystals with high stacking fault energy have a higher probability of forming annealing twins", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查堆垛层错能与退火孪晶形成概率之间的关系，需要理解晶体缺陷和变形机制的基本原理，并进行概念关联和综合分析。虽然不涉及复杂计算，但需要对材料科学中的晶体结构和缺陷行为有较深入的理解。 | 难度: 在选择题中属于较高难度，需要理解晶体堆垛层错能与退火孪晶形成概率之间的关系，并进行综合分析判断。题目涉及中等应用层次的知识，要求考生能够关联多个概念（堆垛层错能、退火孪晶形成机制）并做出正确选择。虽然题目提供了明确选项，但正确解答需要对材料科学中的晶体缺陷行为有较深入的理解，属于复杂分析过程的判断。", "convertible": true, "correct_option": "B. Crystals with low stacking fault energy have a higher probability of forming annealing twins", "choice_question": "The relationship between the probability of annealing twin formation and the stacking fault energy of a crystal is ( ).", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The probability is solely determined by the crystal's Burgers vector magnitude", "B": "Crystals with low stacking fault energy have a higher probability of forming annealing twins", "C": "The probability increases linearly with stacking fault energy according to Read-Shockley equation", "D": "Only face-centered cubic crystals can form annealing twins regardless of stacking fault energy" }, "correct_answer": "B", "explanation": "The correct answer is B because low stacking fault energy facilitates dislocation dissociation into partials, promoting twin formation. Option A is a cognitive bias trap, mixing dislocation theory with twin formation. Option C misapplies the Read-Shockley equation which describes low-angle grain boundaries. Option D exploits the common misconception that FCC structure is essential, while twins can form in other structures given appropriate conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3110, "question": "Hydrogen storage alloys are alloys that form hydrogen-containing solid solutions by absorbing hydrogen, and under certain conditions, these alloys decompose to release hydrogen", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述，并要求判断其正确性（答案以√表示正确），符合判断题的特征 | 知识层次: 题目考查对氢存储合金基本概念的记忆和理解，属于定义和基本原理的记忆性知识。 | 难度: 该题目属于基础概念记忆层次，仅需判断关于储氢合金定义的陈述是否正确。在选择题型中，这种直接考察定义记忆的题目属于最简单的难度等级，不需要复杂的概念理解或分析过程。", "convertible": true, "correct_option": "√", "choice_question": "Hydrogen storage alloys are alloys that form hydrogen-containing solid solutions by absorbing hydrogen, and under certain conditions, these alloys decompose to release hydrogen", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All hydrogen storage alloys exhibit exactly the same hydrogen absorption/desorption pressure plateau characteristics regardless of their chemical composition.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because the hydrogen absorption/desorption pressure plateau characteristics vary significantly among different hydrogen storage alloys depending on their chemical composition and crystal structure. The plateau pressure is highly sensitive to alloy composition and is a critical parameter that determines the operating conditions for hydrogen storage applications. Misunderstanding this concept could lead to improper material selection for specific hydrogen storage applications.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3548, "question": "Why is Babbitt alloy wear-resistant?", "answer": "Because the structural characteristic of tin-based bearing alloy is the distribution of hard particles on a soft matrix. If the structure of the bearing alloy consists of hard particles distributed on a soft matrix, during operation, the soft matrix will wear and become recessed, causing the hard particles to protrude from the matrix. This reduces the contact area between the shaft and the bearing bush, while the recesses can store lubricating oil, lowering the friction coefficient between the shaft and the bearing bush and reducing wear. Additionally, the soft matrix can withstand impact and vibration, allowing the shaft and bearing bush to fit well together and also embed small foreign hard particles, ensuring the shaft journal is not scratched, thus providing excellent wear resistance.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Babbitt合金耐磨的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目不仅需要理解Babbitt合金的基本结构特征，还需要分析其在实际工作条件下的磨损机制、润滑原理以及对外界冲击和振动的响应。这涉及到多个概念的关联和综合运用，以及对材料性能与微观结构之间关系的深入理解。思维过程要求较高的分析能力和推理能力。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解巴氏合金的基本结构特征（硬颗粒分布在软基体上），还需要综合运用材料科学、摩擦学原理和机械工程知识，深入分析这种结构如何通过多个协同机制（接触面积减少、润滑油储存、冲击吸收、异物嵌入等）实现耐磨性。这种需要同时解释复杂结构特征并推导多重作用机理的题目，在选择题型中属于对知识深度和综合分析能力要求极高的类型。", "convertible": true, "correct_option": "Because the structural characteristic of tin-based bearing alloy is the distribution of hard particles on a soft matrix.", "choice_question": "Why is Babbitt alloy wear-resistant?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be converted by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because the structural characteristic of tin-based bearing alloy is the distribution of hard particles on a soft matrix", "B": "Due to its exceptionally high elastic modulus that prevents deformation under load", "C": "Because the alloy forms a self-lubricating oxide layer during operation", "D": "Due to the presence of intermetallic compounds that create a hardened surface layer" }, "correct_answer": "A", "explanation": "The correct answer A describes the actual wear-resistant mechanism of Babbitt alloy where hard particles (SnSb/Cu6Sn5) are embedded in a soft tin matrix, allowing for embedment of foreign particles and conformability. Option B exploits cognitive bias by using a seemingly relevant but incorrect material property (elastic modulus). Option C creates a professional intuition trap by suggesting a plausible but non-applicable mechanism (self-lubrication). Option D sets up a multi-level verification trap by combining partially correct information (intermetallics) with an incorrect conclusion (surface hardening).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3651, "question": "FCC lead has a lattice parameter of 0.4949 nm and contains one vacancy per 500 Pb atoms. Calculate the density.", "answer": "the density is 11.335 g/cm3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解FCC铅的密度，答案是一个具体的数值结果（11.335 g/cm3），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括晶格参数与密度的关系、空位浓度的计算等，需要综合应用材料科学中的基本概念和公式，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解FCC晶体结构、空位浓度、密度计算等多个概念，并进行多步计算和综合分析。虽然题目给出了正确选项，但解题过程涉及单位换算、原子质量应用和综合公式推导，对学生的概念关联和计算能力要求较高。", "convertible": true, "correct_option": "11.335 g/cm3", "choice_question": "FCC lead has a lattice parameter of 0.4949 nm and contains one vacancy per 500 Pb atoms. The density is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "11.335 g/cm³", "B": "11.415 g/cm³", "C": "11.286 g/cm³", "D": "11.512 g/cm³" }, "correct_answer": "A", "explanation": "正确答案A考虑了空位缺陷对密度的实际影响。选项B是忽略空位缺陷的计算结果，利用了AI可能忽略缺陷的认知偏差。选项C错误地使用了面心立方晶胞原子数3.998（500/499）而非正确处理空位浓度，是多层次验证陷阱。选项D是体心立方结构的错误计算结果，利用了晶体结构混淆的专业直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4611, "question": "Why does the magnitude of the saturation magnetization decrease with increasing temperature for ferromagnetic materials?", "answer": "The saturation magnetization decreases with increasing temperature because the atomic thermal vibrational motions counteract the coupling forces between the adjacent atomic dipole moments, causing some magnetic dipole misalignment.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对现象进行文字解释和论述，答案提供了详细的原理说明，符合简答题的特征 | 知识层次: 题目要求解释铁磁材料饱和磁化强度随温度升高而降低的机理，涉及原子热振动与磁偶极矩耦合作用的综合分析，需要理解温度对磁有序状态的影响机制，属于对物理过程的深入推理和机理解释。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The atomic thermal vibrational motions counteract the coupling forces between the adjacent atomic dipole moments, causing some magnetic dipole misalignment.", "choice_question": "Why does the magnitude of the saturation magnetization decrease with increasing temperature for ferromagnetic materials?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The atomic thermal vibrational motions counteract the coupling forces between the adjacent atomic dipole moments, causing some magnetic dipole misalignment", "B": "The increased temperature causes domain wall motion to become irreversible, leading to permanent loss of magnetization", "C": "The Curie temperature represents the point where all magnetic domains simultaneously lose their orientation", "D": "Thermal expansion reduces the density of magnetic atoms per unit volume, directly lowering saturation magnetization" }, "correct_answer": "A", "explanation": "Option A is correct because thermal vibrations disrupt the alignment of magnetic moments. Option B is a trap - while domain walls move, the effect is reversible below Tc. Option C misrepresents the Curie temperature as an abrupt transition rather than gradual. Option D uses a plausible mechanism (thermal expansion) but incorrectly applies it to saturation magnetization which is an intensive property.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1440, "question": "What is the solid solution method of carbon in ferrite?", "answer": "Interstitial", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释碳在铁素体中的固溶方式，答案需要文字描述（\"Interstitial\"），属于简答题类型。 | 知识层次: 题目考查的是碳在铁素体中的固溶方式这一基本概念的记忆和理解，属于材料科学中的基础知识点，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即碳在铁素体中的固溶方式（间隙固溶）。题目仅要求识别正确术语\"Interstitial\"，无需解释或分析，属于最基本的知识点回忆，因此属于等级1难度。", "convertible": true, "correct_option": "Interstitial", "choice_question": "What is the solid solution method of carbon in ferrite?", "conversion_reason": "The answer is a standard term (Interstitial), which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial", "B": "Substitutional", "C": "Vacancy diffusion", "D": "Interstitialcy" }, "correct_answer": "A", "explanation": "The correct answer is A (Interstitial) because carbon atoms are small enough to occupy the interstitial sites in the BCC ferrite lattice. Option B (Substitutional) is incorrect but tempting as it's the primary solid solution mechanism for larger alloying elements. Option C (Vacancy diffusion) exploits confusion between solution mechanism and diffusion process. Option D (Interstitialcy) is a sophisticated trap, referring to a related but different atomic migration mechanism involving both interstitial and substitutional sites.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4195, "question": "What electron subshell is being filled for the actinide series?", "answer": "The 5 f subshell is being filled for the actinide series of elements.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释回答具体的电子亚层，答案是一个简短的文字描述，不需要选择、判断或计算。 | 知识层次: 题目考查对元素周期表中锕系元素电子填充亚层的基本概念记忆，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即对actinide系列元素填充的电子亚层进行直接回忆。题目仅要求识别正确的电子亚层（5f），无需解释或分析多个概念，属于最基础的定义简答级别。", "convertible": true, "correct_option": "The 5 f subshell is being filled for the actinide series of elements.", "choice_question": "Which electron subshell is being filled for the actinide series?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5f subshell", "B": "6d subshell", "C": "7s subshell", "D": "4f subshell" }, "correct_answer": "A", "explanation": "The correct answer is A because the actinide series is characterized by the filling of the 5f electron subshell. Option B is a strong distractor because the 6d subshell is also involved in early actinides, creating a partial filling pattern that can confuse AI models. Option C exploits the tendency to focus on the outermost shell, while option D targets confusion with the lanthanide series which fills the 4f subshell.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 385, "question": "In the composition triangle of the A-B-C ternary system, for all alloys whose composition points lie on a line parallel to the AB side, the content of the (13) component is a fixed value.", "answer": "(13) C", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个具体的成分名称（C），属于需要简短文字回答的题目类型，而不是从多个选项中选择或判断对错 | 知识层次: 题目考查三元相图的基本概念和组成三角形的理解，属于对基本原理的记忆性知识。 | 难度: 在选择题型中，此题属于基础概念记忆题，仅需考生记住三元相图中平行于某边的直线代表第三组元含量固定这一基本原理。题目直接考查定义性知识，无需分析推理，属于最简单的记忆性题目。", "convertible": true, "correct_option": "C", "choice_question": "In the composition triangle of the A-B-C ternary system, for all alloys whose composition points lie on a line parallel to the AB side, the content of which component is a fixed value?", "conversion_reason": "The answer is a standard term (C), which can be presented as a single correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ratio of A to B components", "B": "The sum of A and B components", "C": "The content of C component", "D": "The difference between A and B components" }, "correct_answer": "C", "explanation": "In a ternary composition triangle, lines parallel to the AB side represent alloys with constant C content, as the distance from the AB side (which represents C content) remains unchanged. Option A exploits the common misconception that parallel lines imply constant ratio. Option B creates confusion by suggesting the sum is fixed, which is true for lines connecting pure components but not parallels. Option D introduces a mathematically plausible but compositionally irrelevant relationship.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3677, "question": "Determine the ASTM grain size number if 20 grains/square inch are observed at a magnification of 400 .", "answer": "the astm grain size number is 9.3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过计算确定ASTM晶粒度数值，需要应用公式进行数值计算，答案是一个具体的数值结果。 | 知识层次: 题目涉及基本的ASTM晶粒度计算公式应用，仅需单步计算和直接套用公式，无需多步推理或综合分析。 | 难度: 在选择题中属于简单难度，题目仅需要应用ASTM晶粒度计算公式进行简单计算，无需多个公式组合或复杂分析。虽然涉及单位转换（从400倍放大率转换为实际面积），但计算步骤直接且明确，属于基本公式应用范畴。", "convertible": true, "correct_option": "9.3", "choice_question": "If 20 grains/square inch are observed at a magnification of 400, what is the ASTM grain size number?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "9.3", "B": "8.6", "C": "10.2", "D": "7.9" }, "correct_answer": "A", "explanation": "The correct answer is A (9.3) calculated using the ASTM grain size formula: N = 2^(n-1) where N is grains/square inch at 100x magnification. First, adjust observed grains to 100x: 20 grains * (400/100)^2 = 320 grains. Then solve for n: n = (log320/log2) + 1 ≈ 9.3. Option B (8.6) is a common error from forgetting to square the magnification factor. Option C (10.2) results from incorrectly using linear instead of area scaling. Option D (7.9) comes from miscalculating the logarithm step.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3893, "question": "Bromium has two naturally occurring isotopes: { }^{79} Br, with an atomic weight of 78.918 amu, and { }^{81} Br, with an atomic weight of 80.916 amu. If the average atomic weight for Br is 79.903 amu, calculate the fraction-of-occurrences of these two isotopes.Give your answer to three decimal places.", "answer": "the fraction-of-occurrence of { }^{79}\\mathrm{br} is 0.507, and the fraction-of-occurrence of { }^{81}\\mathrm{br} is 0.493.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解两种同位素的出现分数，答案以具体数值形式给出，需要精确到三位小数。 | 知识层次: 题目需要应用基本的同位素丰度计算公式，进行简单的数值计算，属于直接套用公式的应用层次。虽然涉及多步计算，但思维过程较为直接，不需要复杂的综合分析或推理。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用同位素丰度的基本公式进行计算，但解题步骤相对直接，仅涉及单一公式的套用和简单的代数运算。题目要求计算两种同位素的丰度，属于基本概念的应用，不需要复杂的推理或多步骤的计算。因此，在选择题型内属于等级2的难度。", "convertible": true, "correct_option": "the fraction-of-occurrence of { }^{79}\\mathrm{br} is 0.507, and the fraction-of-occurrence of { }^{81}\\mathrm{br} is 0.493", "choice_question": "Bromium has two naturally occurring isotopes: { }^{79} Br, with an atomic weight of 78.918 amu, and { }^{81} Br, with an atomic weight of 80.916 amu. If the average atomic weight for Br is 79.903 amu, what are the fraction-of-occurrences of these two isotopes?", "conversion_reason": "The answer is a specific numerical result, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.507 for 79Br and 0.493 for 81Br", "B": "0.493 for 79Br and 0.507 for 81Br", "C": "0.500 for both isotopes", "D": "0.600 for 79Br and 0.400 for 81Br" }, "correct_answer": "A", "explanation": "The correct answer is derived by solving the weighted average equation: 78.918x + 80.916(1-x) = 79.903. Option B reverses the fractions, exploiting the tendency to assume the heavier isotope is more abundant. Option C appeals to the false intuition of equal distribution. Option D introduces a plausible-looking but mathematically incorrect ratio that might result from incorrect rounding or unit confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 785, "question": "4.Secondary recrystallization", "answer": "Secondary recrystallization: is an abnormal growth process where a few large grains grow at the expense of fine grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Secondary recrystallization\"进行文字解释和论述，答案是一个定义性的陈述，符合简答题的特征 | 知识层次: 题目考查的是对二次再结晶这一基本概念的定义和简单描述，属于基础概念的记忆和理解层面，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"二次再结晶\"的基本定义，属于基础概念记忆层次。正确选项直接给出了定义描述，无需复杂推理或概念间关联分析，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Secondary recrystallization: is an abnormal growth process where a few large grains grow at the expense of fine grains.", "choice_question": "Which of the following best describes secondary recrystallization?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An abnormal growth process where a few large grains grow at the expense of fine grains", "B": "A uniform grain growth process driven solely by temperature increase", "C": "The initial stage of recrystallization where dislocation density decreases", "D": "A process identical to primary recrystallization but occurring at higher temperatures" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines secondary recrystallization as abnormal grain growth. Option B is a cognitive bias trap - it describes normal grain growth which is temperature-driven but lacks the abnormal aspect. Option C exploits confusion with primary recrystallization stages. Option D is a professional intuition trap, suggesting a simple temperature difference when the mechanisms fundamentally differ.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 417, "question": "3. The factors influencing the formation of substitutional solid solutions are _ (8)", "answer": "Electronegativity", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写影响置换固溶体形成的因素，答案需要提供具体的文字解释（如电负性），而不是从选项中选择或进行数值计算。 | 知识层次: 题目考查对置换固溶体形成影响因素的基础概念记忆，属于基本原理的识记范畴 | 难度: 在选择题型中，该题目仅要求记忆基础概念中的单一因素（电负性），不需要解释或比较多个概念，属于最基础的定义简答级别。", "convertible": true, "correct_option": "Electronegativity", "choice_question": "Which of the following factors influences the formation of substitutional solid solutions?", "conversion_reason": "The answer is a standard term (Electronegativity), making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Electronegativity difference <15%", "B": "Crystal structure compatibility", "C": "Atomic radius difference <5%", "D": "All of the above" }, "correct_answer": "A", "explanation": "The correct answer is A because electronegativity difference is the primary factor for substitutional solid solutions (Hume-Rothery rules). B is a strong distractor as crystal structure compatibility seems logically important but is actually secondary. C uses the common 15% radius rule but reverses the percentage to create confusion. D combines all options to exploit confirmation bias in AI systems that tend to favor inclusive answers.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2064, "question": "Point out the errors in the following concepts and correct them: (6) In liquid metal, any embryo that emerges with a radius smaller than the critical nucleus radius cannot nucleate, but as long as there is sufficient energy fluctuation to provide the nucleation work, nucleation is still possible.", "answer": "Nucleation cannot occur, even if there is sufficient energy fluctuation to provide it, nucleation still cannot occur.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求指出概念中的错误并纠正，类似于判断陈述的对错并给出正确解释 | 知识层次: 题目考查对成核基本概念的记忆和理解，特别是临界核半径和能量波动在成核过程中的作用。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度。题目要求考生理解临界核半径的概念以及成核的基本原理，并能够判断在能量波动足够的情况下，半径小于临界核半径的胚团是否能够成核。虽然涉及基础概念的记忆，但需要一定的理解深度来判断陈述的正确性，因此属于中等难度。", "convertible": true, "correct_option": "Nucleation cannot occur, even if there is sufficient energy fluctuation to provide it, nucleation still cannot occur.", "choice_question": "Point out the errors in the following concepts and correct them: (6) In liquid metal, any embryo that emerges with a radius smaller than the critical nucleus radius cannot nucleate, but as long as there is sufficient energy fluctuation to provide the nucleation work, nucleation is still possible.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In liquid metal, any embryo with radius smaller than critical nucleus radius can never nucleate under any circumstances, including extreme energy fluctuations.", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "The statement is correct because nucleation is fundamentally impossible for embryos below the critical radius. While energy fluctuations can affect the probability of reaching the critical size, they cannot enable nucleation below this thermodynamic threshold. The misconception lies in thinking energy fluctuations can overcome the fundamental thermodynamic barrier, when in reality they only help reach the critical size where nucleation becomes possible.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2798, "question": "Calculate the total migration distance $S$ of carbon atoms, given the carbon atom jump frequency as $\\Gamma=1.7\\times10^{9}/\\mathrm{s}$, jump distance as $2.53\\times10^{-10}\\mathrm{m}$, and time as $4\\mathrm{h}$.", "answer": "$4\\mathrm{h}=4\\times3600\\mathrm{s}$, $S=\\Gamma \\cdot t \\cdot r=1.7\\times10^{9}\\times4\\times3600\\times2.53\\times10^{-10}=6193\\mathrm{m}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及单位转换和乘法运算，最终给出具体的计算结果。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，即利用给定的参数（跳频、跳跃距离和时间）通过公式计算迁移距离。虽然需要单位转换，但整体思维过程较为直接，不涉及多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算，解题步骤简单，仅涉及基本公式应用和简单计算，无需多个公式组合或复杂分析，因此属于最低难度等级。", "convertible": true, "correct_option": "6193m", "choice_question": "Calculate the total migration distance $S$ of carbon atoms, given the carbon atom jump frequency as $\\Gamma=1.7\\times10^{9}/\\mathrm{s}$, jump distance as $2.53\\times10^{-10}\\mathrm{m}$, and time as $4\\mathrm{h}$.", "conversion_reason": "The calculation yields a specific numerical answer, making it suitable for conversion into a multiple-choice question format where the correct option is the calculated result.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6193 m", "B": "0.619 m", "C": "1.72×10^6 m", "D": "2.53×10^-10 m" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula S = √(6Dt), where D = Γd²/6. Plugging in the values gives S = 6193 m. Option B is a common error from forgetting to square root the result. Option C results from incorrectly using Γ directly without considering jump distance. Option D is the single jump distance, misleading those who don't consider cumulative migration.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1449, "question": "Compared to pure iron, how do the strength and hardness of ferrite change?", "answer": "Higher", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和比较纯铁和铁素体的强度和硬度变化，答案需要文字说明而非选择、判断或计算 | 知识层次: 题目考查对纯铁和铁素体强度与硬度差异的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆基础概念（纯铁与铁素体的强度硬度比较），属于直接回忆定义和分类的基础知识。题目仅提供正确选项\"Higher\"，不需要任何解释或分析步骤，因此属于最简单的难度等级。", "convertible": true, "correct_option": "Higher", "choice_question": "Compared to pure iron, how do the strength and hardness of ferrite change?", "conversion_reason": "The answer is a standard term that can be presented as a single correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Higher", "B": "Lower", "C": "Same as pure iron", "D": "Depends on the carbon content" }, "correct_answer": "A", "explanation": "Ferrite, being a solid solution of carbon in iron, has higher strength and hardness than pure iron due to solid solution strengthening. Option B exploits the cognitive bias that impurities might weaken the material. Option C is a common oversimplification trap. Option D is a professional intuition trap, as while carbon content affects properties, the question specifically compares to pure iron where ferrite is always stronger.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2048, "question": "What is a critical nucleus?", "answer": "According to the relationship between free energy and the radius of an embryo, it can be known that embryos with radius rr_k have the potential to nucleate; while embryos with r=r_k may either disappear or grow stably. Therefore, an embryo with radius r_k is called a critical nucleus. Its physical meaning is that the short-range ordered atomic clusters emerging in the undercooled liquid can become nuclei and grow when their size r≥r_k.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"critical nucleus\"进行文字解释和论述，答案提供了详细的定义和物理意义的描述，符合简答题的特征。 | 知识层次: 题目考查对临界核（critical nucleus）这一基本概念的定义和物理意义的记忆和理解，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解并解释\"critical nucleus\"的定义及其物理意义，而不仅仅是简单的定义复述。题目要求考生能够描述胚胎半径与自由能之间的关系，并解释临界核的物理含义，这比单纯记忆定义要复杂一些。然而，题目并未涉及多个概念的比较分析或复杂概念体系的阐述，因此不属于最高难度等级。", "convertible": true, "correct_option": "An embryo with radius r_k that may either disappear or grow stably, and is the threshold size for nucleation.", "choice_question": "What is a critical nucleus?", "conversion_reason": "The answer is a standard definition of a critical nucleus, which can be presented as a correct option in a multiple-choice question format. The question can be rephrased to fit a multiple-choice format by asking for the definition or description of a critical nucleus.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An embryo with radius r_k that may either disappear or grow stably, and is the threshold size for nucleation", "B": "The smallest possible crystal structure unit that can exist in a given material system", "C": "A nucleus that has reached the minimum energy configuration required for phase transformation", "D": "The point defect cluster with critical concentration to initiate recrystallization" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines the thermodynamic concept of critical nucleus in nucleation theory. Option B exploits confusion with unit cell concepts in crystallography. Option C sounds plausible but incorrectly focuses on energy configuration rather than size threshold. Option D strategically misdirects by combining valid concepts (point defects and recrystallization) in an invalid context for nucleation theory.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3346, "question": "In eutectoid steel, both pearlite and tempered martensite (assuming tempered at 400°C) consist of ferrite and carbide. Why do the morphology and dispersion of carbides in tempered martensite differ from those in pearlite?", "answer": "The carbides in pearlite exhibit a lamellar morphology with low dispersion, whereas the carbides in martensite are fine particles with high dispersion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么回火马氏体和珠光体中的碳化物形态和分散度不同，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释珠光体和回火马氏体中碳化物的形态和分散性差异的原因，这需要深入理解相变过程、显微组织形成机制以及热处理对组织的影响。涉及多个概念的关联和综合分析，需要推理和机理解释，属于较高层次的认知要求。 | 难度: 在选择题中属于最高难度，需要深入理解珠光体和回火马氏体的微观结构差异及其形成机理。题目要求综合运用相变动力学、晶体学知识和热处理原理，对碳化物的形态和分布进行机理层面的对比分析。这种复杂现象的全方位分析在选择题型中属于认知要求最高的类型。", "convertible": true, "correct_option": "The carbides in pearlite exhibit a lamellar morphology with low dispersion, whereas the carbides in martensite are fine particles with high dispersion.", "choice_question": "In eutectoid steel, both pearlite and tempered martensite (assuming tempered at 400°C) consist of ferrite and carbide. Why do the morphology and dispersion of carbides in tempered martensite differ from those in pearlite?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The carbides in pearlite exhibit a lamellar morphology with low dispersion, whereas the carbides in martensite are fine particles with high dispersion", "B": "The higher tempering temperature of martensite causes complete dissolution of carbides, resulting in uniform dispersion", "C": "Pearlite forms through diffusion-controlled transformation, while martensite undergoes shear transformation followed by carbide precipitation", "D": "The carbon content in martensite is higher than in pearlite, leading to finer carbide distribution" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the morphological differences between pearlite and tempered martensite. Option B is incorrect because 400°C tempering does not cause complete carbide dissolution. Option C contains partial truth about transformation mechanisms but fails to explain the morphological differences. Option D is misleading as both structures have the same overall carbon content in eutectoid steel.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4671, "question": "Iron titanate, FeTiO3, forms in the ilmenite crystal structure that consists of an HCP arrangement of O2- ions. What fraction of the total tetrahedral sites will be occupied?", "answer": "Since both Fe2+ and Ti4+ ions occupy octahedral sites, no tetrahedral sites will be occupied.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述特定晶体结构中四面体位点的占据情况，答案提供了文字解释而非数值计算或选择判断 | 知识层次: 题目需要理解ilmenite晶体结构中O2-离子的HCP排列方式，并分析Fe2+和Ti4+离子占据的八面体位点情况，进而推断四面体位点的占据情况。这涉及到多步的概念关联和综合分析，而不仅仅是简单的记忆或直接应用。 | 难度: 在选择题型中，该题目属于较高难度，需要考生掌握以下知识点并进行多角度分析：", "convertible": true, "correct_option": "No tetrahedral sites will be occupied.", "choice_question": "In the ilmenite crystal structure of FeTiO3, which consists of an HCP arrangement of O2- ions, what fraction of the total tetrahedral sites will be occupied?", "conversion_reason": "The answer is a definitive statement that can be directly converted into a single correct option for a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1/3 of tetrahedral sites are occupied by Fe2+", "B": "1/2 of tetrahedral sites are occupied by Ti4+", "C": "All tetrahedral sites remain vacant", "D": "1/4 of tetrahedral sites are randomly occupied by Fe2+ and Ti4+" }, "correct_answer": "C", "explanation": "In the ilmenite structure (FeTiO3), the O2- ions form an HCP lattice but the cations occupy octahedral sites exclusively. The tetrahedral sites remain completely unoccupied, which is a distinctive feature of this structure type. This challenges the common assumption that cations will occupy any available sites. Option A exploits the expectation that Fe2+ should occupy some sites. Option B plays on the tendency to assign higher-valent ions to tetrahedral coordination. Option D creates confusion by suggesting partial occupancy, which occurs in other structures but not here.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 5, "correct_answers": 5, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 44, "question": "Barium titanate is an important ferroelectric ceramic, and its crystal type is perovskite structure. What lattice does it belong to?", "answer": "It belongs to the cubic crystal system", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案是一个简短的陈述，而不是从多个选项中选择或进行数值计算。 | 知识层次: 题目考查对钛酸钡晶体结构类型的基础概念记忆，仅需回答其所属晶系，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即钡钛矿的晶体结构类型。题目直接给出了正确选项，无需进行复杂的分析或推理，属于最基本的知识点掌握要求。", "convertible": true, "correct_option": "It belongs to the cubic crystal system", "choice_question": "Barium titanate is an important ferroelectric ceramic, and its crystal type is perovskite structure. What lattice does it belong to?", "conversion_reason": "The answer is a standard term (cubic crystal system), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cubic", "B": "Tetragonal", "C": "Orthorhombic", "D": "Rhombohedral" }, "correct_answer": "A", "explanation": "The correct answer is A because barium titanate at room temperature has a perovskite structure that belongs to the cubic crystal system. Option B is a strong distractor because barium titanate undergoes a phase transition to tetragonal below 120°C, which may confuse AI models relying on temperature-dependent data. Option C exploits the orthorhombic phase that appears at lower temperatures (-90°C to -80°C), creating a multi-level verification trap. Option D targets the rhombohedral phase that exists below -90°C, leveraging the material's complex polymorphism to induce errors in systems that don't properly account for temperature conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3004, "question": "When a factory used a nylon rope sling that had been in stock for two years, a fracture accident occurred even though the load-bearing capacity was far greater than the lifting stress. The reason for the fracture was (1).", "answer": "(1)aging", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释断裂原因，需要文字解释和论述，答案形式为简短的文字描述而非选择或判断 | 知识层次: 题目考查对材料老化这一基本概念的记忆和理解，不需要复杂的分析或计算。 | 难度: 在选择题型中属于基础难度，仅需要记忆材料老化的基本概念即可作答，无需复杂分析或概念比较。题目直接考查对\"aging\"这一基础定义的识别能力。", "convertible": true, "correct_option": "aging", "choice_question": "When a factory used a nylon rope sling that had been in stock for two years, a fracture accident occurred even though the load-bearing capacity was far greater than the lifting stress. The reason for the fracture was:", "conversion_reason": "The answer is a standard term (aging), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hydrolysis-induced chain scission from ambient moisture absorption", "B": "Stress concentration at manufacturing defects", "C": "Viscoelastic creep deformation under sustained load", "D": "UV-induced crosslinking from improper storage" }, "correct_answer": "A", "explanation": "The correct answer is A because nylon is particularly susceptible to hydrolysis over time, which breaks polymer chains and reduces strength. Option B exploits the common intuition that manufacturing defects cause failure, but the two-year storage period points to degradation. Option C uses a real phenomenon (creep) but incorrectly applies it to a sudden fracture scenario. Option D reverses the actual UV effect (chain scission) to mislead those with partial knowledge.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3123, "question": "What are the main uses of superconductors?", "answer": "Superconductors can not only be used in superconducting generators, but also prove effective in applications such as superconducting motors, superconducting power transmission, superconducting energy storage, maglev trains, magnetohydrodynamic power generation, and nuclear fusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举超导体的主要用途，答案以文字解释和论述的形式给出，没有选项、对错判断或数值计算的要求。 | 知识层次: 题目考查对超导体主要用途的记忆和理解，属于基础概念的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求记忆超导体的主要用途，但正确选项列举了多个应用领域，需要考生对超导体的应用有较全面的了解。这超出了基本定义的简答（等级1），但尚未达到需要阐述复杂概念体系（等级3）的程度。因此，该题目属于概念解释和描述的难度等级（等级2）。", "convertible": true, "correct_option": "Superconductors can not only be used in superconducting generators, but also prove effective in applications such as superconducting motors, superconducting power transmission, superconducting energy storage, maglev trains, magnetohydrodynamic power generation, and nuclear fusion.", "choice_question": "Which of the following describes the main uses of superconductors?", "conversion_reason": "The answer is a detailed and specific description of the uses of superconductors, which can be presented as a correct option in a multiple-choice question. The original question can be rephrased to fit a multiple-choice format by asking for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Superconductors can not only be used in superconducting generators, but also prove effective in applications such as superconducting motors, superconducting power transmission, superconducting energy storage, maglev trains, magnetohydrodynamic power generation, and nuclear fusion.", "B": "Superconductors are primarily used in high-temperature applications like jet engine components and thermal barrier coatings due to their zero resistance property at elevated temperatures.", "C": "The main use of superconductors is in structural engineering for building lightweight bridges and skyscrapers, taking advantage of their high strength-to-weight ratio.", "D": "Superconductors find their most important application in consumer electronics as replacement materials for silicon chips, enabling faster computing speeds at room temperature." }, "correct_answer": "A", "explanation": "The correct answer A comprehensively lists the actual main applications of superconductors across various fields. Option B is a temperature misconception trap, falsely suggesting superconductors work at high temperatures (they actually require cryogenic conditions). Option C exploits material property confusion by attributing structural properties to superconductors. Option D creates a silicon replacement fallacy, ignoring the fundamental temperature limitations of superconductors in everyday applications.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2086, "question": "In the Al-Cu phase diagram, given $K=0.16$, $m=3.2$. If the solidification rate of the casting is $R=3\\\\times10^{-4}~\\\\mathrm{cm/s}$, the temperature gradient is $G=30^{\\\\circ}\\\\mathrm{C}/\\\\mathrm{cm}$, and the diffusion coefficient is $D=3\\\\times10^{-5}~\\\\mathrm{cm}^{2}/\\\\mathrm{s}$, find the extreme value of $\\\\scriptstyle{\\\\mathcal{W}}_{\\\\mathrm{Cu}}$ in the alloy that maintains planar interface growth.", "answer": "$w_{\\\\mathrm{Cu}}^{\\\\mathrm{C}_{0}}=\\\\frac{G D}{R m}\\\\frac{K}{1-K}=0.1744$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的参数和公式进行数值计算，最终得出一个具体的数值答案。解答过程涉及公式应用和数值代入，属于典型的计算题。 | 知识层次: 题目需要进行多步计算，涉及相图参数的理解和公式应用，需要将给定的参数代入公式进行计算，并理解平面界面生长的条件。虽然计算过程较为直接，但需要对相图和扩散系数等概念有一定的理解，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解相图、扩散系数、凝固速率等多个概念，并进行多步计算和综合分析。题目涉及多个变量的代入和公式推导，但作为选择题，正确选项已经给出，减少了部分计算复杂度。", "convertible": true, "correct_option": "0.1744", "choice_question": "In the Al-Cu phase diagram, given $K=0.16$, $m=3.2$. If the solidification rate of the casting is $R=3\\times10^{-4}~\\mathrm{cm/s}$, the temperature gradient is $G=30^{\\circ}\\mathrm{C}/\\mathrm{cm}$, and the diffusion coefficient is $D=3\\times10^{-5}~\\mathrm{cm}^{2}/\\mathrm{s}$, what is the extreme value of $\\scriptstyle{\\mathcal{W}}_{\\mathrm{Cu}}$ in the alloy that maintains planar interface growth?", "conversion_reason": "The calculation problem has a definite numerical answer, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1744", "B": "0.2018", "C": "0.1542", "D": "0.1896" }, "correct_answer": "A", "explanation": "正确答案A是通过严格应用成分过冷判据公式计算得出：W_Cu = (G*D)/(m*R*(1-K)) = (30×3×10^-5)/(3.2×3×10^-4×0.84) = 0.1744。干扰项B通过错误地忽略(1-K)项得出；干扰项C错误地将温度梯度单位转换为K/cm导致；干扰项D则是混淆了Al-Cu与Al-Si体系的典型分配系数K值。这些干扰项都利用了材料科学计算中常见的单位混淆、参数误用和体系类比错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 102, "question": "If the partial pressure of surrounding oxygen is increased, how will the density of the non-stoichiometric compound Zn1+xO change? Increase or decrease? Why?", "answer": "Zn (g) →Zni· +e Zn (g) +1/2O2=ZnO Zn:+e’+1/2O→ZnO [ZnO]=[e'] PO2↑,[Zni]↓", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释非化学计量化合物Zn1+xO的密度如何随周围氧气分压的变化而变化，并需要提供原因。答案中包含了化学反应方程式和文字解释，符合简答题的特征。 | 知识层次: 题目需要综合运用非化学计量化合物、缺陷化学、质量作用定律等知识，通过分析氧分压变化对缺陷浓度的影响机制来解释Zn1+xO密度的变化。这涉及多概念关联和机理解释，属于较高层次的综合分析能力。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Increase", "choice_question": "If the partial pressure of surrounding oxygen is increased, how will the density of the non-stoichiometric compound Zn1+xO change?", "conversion_reason": "The answer to the question is a straightforward choice between 'Increase' or 'decrease', making it suitable for conversion to a multiple-choice format. The provided answer indicates that the density will increase, hence 'Increase' is the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increase due to incorporation of interstitial oxygen atoms", "B": "Decrease due to formation of zinc vacancies", "C": "Remain unchanged as the crystal structure is unaffected", "D": "First decrease then increase due to competing defect mechanisms" }, "correct_answer": "A", "explanation": "The correct answer is A because increasing oxygen partial pressure leads to incorporation of interstitial oxygen, increasing the overall density. Option B is a common misconception where zinc vacancy formation is incorrectly assumed to dominate. Option C exploits the AI's tendency to default to 'no change' answers for complex systems. Option D uses a sophisticated-sounding but physically incorrect two-stage mechanism to trap advanced models.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 718, "question": "Types and quantitative relationship of voids", "answer": "When equal-sized spheres are closely packed, the main types of voids are octahedral voids and tetrahedral voids. When $\\pmb{n}$ spheres are closely packed, there will be $\\textbf{\\em n}$ octahedral voids and $2n$ tetrahedral voids", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释紧密堆积中空隙的类型和数量关系，答案提供了详细的文字解释和定量关系，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，主要涉及空隙的类型和数量关系，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生掌握两种空隙类型（八面体空隙和四面体空隙）的定义及其数量关系。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。题目要求考生能够理解和描述空隙类型及其数量关系，符合等级2的难度标准。", "convertible": true, "correct_option": "When equal-sized spheres are closely packed, the main types of voids are octahedral voids and tetrahedral voids. When n spheres are closely packed, there will be n octahedral voids and 2n tetrahedral voids", "choice_question": "Which of the following correctly describes the types and quantitative relationship of voids when equal-sized spheres are closely packed?", "conversion_reason": "The answer is a standard description of a concept in materials science, which can be rephrased as a multiple-choice question by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "n octahedral voids and 2n tetrahedral voids", "B": "2n octahedral voids and n tetrahedral voids", "C": "n octahedral voids and n tetrahedral voids", "D": "2n octahedral voids and 2n tetrahedral voids" }, "correct_answer": "A", "explanation": "The correct answer is A because in close packing of equal-sized spheres, the number of octahedral voids equals the number of spheres (n), while tetrahedral voids are twice the number of spheres (2n). Option B reverses this relationship, exploiting the common confusion between the two void types. Option C creates a false symmetry by making both voids equal, appealing to an incorrect intuitive assumption. Option D doubles both counts, targeting those who might misremember the exact ratios but recall both voids scale with n.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1091, "question": "What are the characteristics of the room temperature tensile curve of aluminum alloy?", "answer": "Aluminum alloy does not exhibit a distinct yield point phenomenon.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和论述铝合金室温拉伸曲线的特征，答案提供了文字解释而非选择或判断 | 知识层次: 题目考查对铝合金室温拉伸曲线特性的基本概念记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对铝合金室温拉伸曲线特性的基础记忆性知识，正确选项直接给出了明确的特征描述（不表现明显屈服点现象），不需要进行概念解释或复杂分析。这属于最基本的概念记忆层次，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Aluminum alloy does not exhibit a distinct yield point phenomenon.", "choice_question": "Which of the following is a characteristic of the room temperature tensile curve of aluminum alloy?", "conversion_reason": "The answer is a standard statement about the characteristics of aluminum alloy, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Exhibits continuous yielding without a distinct yield point", "B": "Shows a sharp yield drop similar to low-carbon steel", "C": "Demonstrates a double yield point phenomenon", "D": "Has a yield plateau followed by strain hardening" }, "correct_answer": "A", "explanation": "Aluminum alloys typically show continuous yielding without a distinct yield point due to their FCC structure and multiple slip systems. Option B exploits the cognitive bias of associating yield behavior with the well-known yield drop in low-carbon steel. Option C creates confusion with materials showing Lüders band propagation. Option D mimics the behavior of some polymers or shape memory alloys, playing on the expectation of distinct yield phases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1525, "question": "For a screw dislocation line, the direction of its cross-slip motion is __(22)__ to the Burgers vector", "answer": "(22) perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（perpendicular）来描述螺位错线的交叉滑移方向与Burgers矢量的关系，属于需要简短文字回答的题目类型。 | 知识层次: 题目考查对螺位错运动方向与伯格斯矢量关系的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即螺位错线滑移方向与伯格斯矢量之间的关系。题目直接给出了正确选项，无需复杂的推理或分析，属于最基本的概念记忆题。", "convertible": true, "correct_option": "perpendicular", "choice_question": "For a screw dislocation line, the direction of its cross-slip motion is __ to the Burgers vector", "conversion_reason": "The answer is a standard term (perpendicular), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "parallel", "B": "perpendicular", "C": "at 45°", "D": "dependent on the slip plane orientation" }, "correct_answer": "B", "explanation": "The correct answer is B (perpendicular) because cross-slip of a screw dislocation occurs when the dislocation moves from one slip plane to another parallel slip plane, requiring the motion to be perpendicular to the Burgers vector. Option A is a cognitive bias trap, as one might intuitively associate dislocation motion with being parallel to the Burgers vector. Option C exploits the common 45° angle seen in many dislocation interactions. Option D is a multi-level verification trap, appearing correct because slip plane orientation matters for edge dislocations, but not for screw dislocation cross-slip.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2260, "question": "What is the difference between continuous and discontinuous precipitation?", "answer": "If precipitation occurs simultaneously throughout the parent phase, and the composition of the parent phase changes continuously with the formation of the new phase, but the grain morphology and orientation remain unchanged, it is called continuous precipitation. In contrast to continuous precipitation, when precipitation occurs, the solid solution within a certain range around it immediately changes from a supersaturated state to a saturated state, forming a distinct interface with the original composition of the parent phase. After nucleation at grain boundaries, it grows into the grain interior with an alternating lamellar distribution. Not only does the composition change abruptly at the interface, but the orientation also changes, which is called discontinuous precipitation. The main difference lies in the length of the diffusion path. In the former, the diffusion field extends over a considerable distance, while in the latter, the diffusion distance is only on the order of the lamellar spacing (generally less than 1 μm).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释连续和不连续沉淀的区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释连续和不连续析出的区别，涉及对析出过程的理解、扩散路径的分析以及微观结构的描述。虽然包含基础概念，但需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅要理解连续和不连续析出的基本概念，还需要掌握两者在析出过程中的微观结构变化、成分变化、取向变化等多方面的差异。解题时需要综合分析多个知识点，包括扩散路径长度、界面特性、析出形态等，并进行多角度的比较分析。这种深度和广度的知识要求，使得该题目在选择题型中属于较难的水平。", "convertible": true, "correct_option": "If precipitation occurs simultaneously throughout the parent phase, and the composition of the parent phase changes continuously with the formation of the new phase, but the grain morphology and orientation remain unchanged, it is called continuous precipitation. In contrast to continuous precipitation, when precipitation occurs, the solid solution within a certain range around it immediately changes from a supersaturated state to a saturated state, forming a distinct interface with the original composition of the parent phase. After nucleation at grain boundaries, it grows into the grain interior with an alternating lamellar distribution. Not only does the composition change abruptly at the interface, but the orientation also changes, which is called discontinuous precipitation. The main difference lies in the length of the diffusion path. In the former, the diffusion field extends over a considerable distance, while in the latter, the diffusion distance is only on the order of the lamellar spacing (generally less than 1 μm).", "choice_question": "What is the difference between continuous and discontinuous precipitation?", "conversion_reason": "The answer is a standard explanation of the difference between continuous and discontinuous precipitation, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Continuous precipitation maintains the parent phase orientation while discontinuous alters it, with diffusion distances differing by orders of magnitude", "B": "Both types preserve crystal orientation, but discontinuous precipitation occurs faster due to higher nucleation rates at grain boundaries", "C": "The key difference is temperature dependence: continuous occurs isothermally while discontinuous requires rapid quenching", "D": "Discontinuous precipitation forms spherical precipitates while continuous creates lamellar structures" }, "correct_answer": "A", "explanation": "Option A correctly identifies the orientation preservation in continuous vs discontinuous precipitation and the critical diffusion distance difference. Option B is wrong because discontinuous precipitation does alter orientation. Option C is a temperature-based distraction unrelated to the actual mechanism. Option D reverses the typical microstructural characteristics of these processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4173, "question": "Relative to electrons and electron states, what does the l quantum number specify?", "answer": "The l quantum number designates the electron subshell.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对量子数l的含义进行文字解释，答案是一个简短的论述性回答，而非选择、判断或计算。 | 知识层次: 题目考查对量子数l的基本定义和分类的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆l量子数的基本定义和功能，属于最基础的概念记忆层次。题目直接给出正确选项，无需任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The l quantum number designates the electron subshell.", "choice_question": "Relative to electrons and electron states, what does the l quantum number specify?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The electron subshell (orbital shape)", "B": "The principal energy level", "C": "The electron spin orientation", "D": "The magnetic moment projection" }, "correct_answer": "A", "explanation": "The correct answer is A because the l quantum number (azimuthal quantum number) specifically describes the shape of the orbital/subshell (s=0, p=1, d=2, f=3). Option B is a common confusion as n specifies the principal energy level. Option C exploits spin-related confusion (specified by ms). Option D targets magnetic properties (specified by ml). Advanced AI might misassign these due to quantum number interrelationships.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4743, "question": "Consider a cylindrical nickel wire 2.0 mm(0.08 in.) in diameter and 3 × 10^{4}mm (1200 in.) long. Calculate its elongation when a load of 300N\\left(67 lb^{2}\\right) is applied. Assume that the deformation is totally elastic.", "answer": "the elongation of the nickel wire is 13.8mm (0.53 in.).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（如弹性变形公式）来求解镍丝的伸长量，答案是一个具体的数值结果（13.8mm），符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即胡克定律和弹性变形公式的直接套用，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，需要应用胡克定律的基本公式（应力=弹性模量×应变）进行简单计算。虽然涉及单位转换和代数运算，但解题步骤直接且无需多个公式组合，因此属于等级2难度。", "convertible": true, "correct_option": "13.8mm (0.53 in.)", "choice_question": "Consider a cylindrical nickel wire 2.0 mm(0.08 in.) in diameter and 3 × 10^{4}mm (1200 in.) long. When a load of 300N(67 lb^{2}) is applied and assuming that the deformation is totally elastic, what is its elongation?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "13.8 mm (0.53 in.)", "B": "6.9 mm (0.27 in.)", "C": "27.6 mm (1.06 in.)", "D": "3.45 mm (0.13 in.)" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using Hooke's Law with nickel's elastic modulus (207 GPa). Option B is half the correct value, exploiting the common mistake of forgetting to square the radius in the cross-sectional area calculation. Option C doubles the correct value, targeting those who might confuse diameter with radius. Option D is one-fourth the correct value, designed to catch those who might incorrectly use shear modulus instead of elastic modulus.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 311, "question": "Are there differences in the atomic stacking modes and packing densities between face-centered cubic and hexagonal close-packed metals? Please explain.", "answer": "FCC stacks in the ABCABC sequence, while HCP stacks in the ABABAB sequence; there is no difference in packing density, both are 0.74.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释面心立方和六方密堆积金属的原子堆垛方式和堆积密度差异，答案需要文字论述和解释，而非选择、判断或计算。 | 知识层次: 题目考查对FCC和HCP两种晶体结构的基本概念的记忆和理解，包括它们的原子堆垛顺序和堆积密度。不需要复杂的计算或综合分析，只需直接回答基本概念即可。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个晶体结构（FCC和HCP）的比较，但正确选项直接给出了明确的序列差异和相同的堆积密度，不需要复杂的推导或分析。主要考察的是对基础概念的记忆和简单对比，符合等级2的概念解释和描述要求。", "convertible": true, "correct_option": "FCC stacks in the ABCABC sequence, while HCP stacks in the ABABAB sequence; there is no difference in packing density, both are 0.74.", "choice_question": "What are the differences in the atomic stacking modes and packing densities between face-centered cubic and hexagonal close-packed metals?", "conversion_reason": "The answer is a standard explanation that can be presented as a single correct option among possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "FCC: ABCABC stacking with 12 nearest neighbors; HCP: ABAB stacking with 12 nearest neighbors - identical coordination but different slip systems", "B": "FCC has higher packing density (0.82) due to more efficient tetrahedral voids utilization compared to HCP (0.74)", "C": "HCP achieves higher density (0.78) through anisotropic compression of octahedral sites along the c-axis", "D": "Both have ABAB stacking but FCC allows more deformation modes due to cubic symmetry" }, "correct_answer": "A", "explanation": "Correct answer A states the true stacking sequences and identical 12-coordination, while noting the real difference in slip systems. Option B falsely claims different packing densities by misapplying void analysis. Option C introduces a non-existent anisotropic compression effect. Option D incorrectly states identical stacking sequences, playing on cubic symmetry confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2733, "question": "Can the new dislocation generated by the dislocation reaction $$ \\\\frac{a}{2}[10\\\\overline{{{1}}}] + \\\\frac{a}{6}[\\\\overline{{{1}}}21] \\\\rightarrow \\\\frac{a}{3}[11\\\\overline{{{1}}}] $$ move on the slip plane?", "answer": "The dislocation line of the new dislocation $\\\\frac{a}{3}[11\\\\overline{{{1}}}]$ is located at the intersection of (111) and (111) planes on the (001) plane, and it is a pure edge dislocation. Since the (001) plane is a non-close-packed plane in fcc, it cannot move and is a fixed dislocation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释新生成的位错是否能在滑移面上移动，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目涉及位错反应和位错运动的综合分析，需要理解位错的性质、滑移面的选择以及非密排面的影响，属于复杂分析和机理解释的范畴。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The dislocation line of the new dislocation $\\frac{a}{3}[11\\overline{{{1}}}]$ is located at the intersection of (111) and (111) planes on the (001) plane, and it is a pure edge dislocation. Since the (001) plane is a non-close-packed plane in fcc, it cannot move and is a fixed dislocation.", "choice_question": "Can the new dislocation generated by the dislocation reaction $$ \\frac{a}{2}[10\\overline{{{1}}}] + \\frac{a}{6}[\\overline{{{1}}}21] \\rightarrow \\frac{a}{3}[11\\overline{{{1}}}] $$ move on the slip plane?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be presented as is, with the answer serving as the correct choice among possible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because the Burgers vector is parallel to the (111) slip plane", "B": "Yes, because the reaction product has a smaller Burgers vector magnitude", "C": "No, because the new dislocation is a pure edge type on a non-slip plane", "D": "No, because the reaction violates the Frank's rule for dislocation energy" }, "correct_answer": "C", "explanation": "The correct answer is C because the new dislocation is a pure edge dislocation located on the (001) plane, which is a non-close-packed plane in FCC crystals and thus cannot move. Option A is incorrect because although the Burgers vector is parallel to (111), the dislocation line itself is not in that plane. Option B exploits the common misconception that smaller Burgers vectors always imply mobility. Option D is a deep trap using Frank's rule which is actually satisfied in this reaction (energy decreases), making this a sophisticated but wrong reason for immobility.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1300, "question": "What are the differences in the driving forces among recrystallization, primary recrystallization, and secondary recrystallization?", "answer": "The driving force for recrystallization is the free energy difference between the new and old phases, for primary recrystallization it is the stored energy, and for secondary recrystallization it is the interfacial energy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述不同再结晶过程的驱动力差异，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目要求区分三种再结晶过程的驱动力，涉及多个概念的关联和综合分析，需要理解不同再结晶阶段的能量来源及其差异，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求区分三种再结晶过程的驱动力，涉及对材料科学中相变和能量概念的综合理解。虽然题目提供了明确的选项，但需要考生掌握不同再结晶过程的本质差异，并能准确关联到相应的驱动力来源。这需要一定的概念关联和综合分析能力，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "The driving force for recrystallization is the free energy difference between the new and old phases, for primary recrystallization it is the stored energy, and for secondary recrystallization it is the interfacial energy.", "choice_question": "What are the differences in the driving forces among recrystallization, primary recrystallization, and secondary recrystallization?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization: stored energy; Primary recrystallization: free energy difference; Secondary recrystallization: interfacial energy", "B": "Recrystallization: interfacial energy; Primary recrystallization: stored energy; Secondary recrystallization: free energy difference", "C": "Recrystallization: free energy difference; Primary recrystallization: stored energy; Secondary recrystallization: interfacial energy", "D": "Recrystallization: stored energy; Primary recrystallization: interfacial energy; Secondary recrystallization: free energy difference" }, "correct_answer": "C", "explanation": "The correct answer is C because: 1) Recrystallization is driven by the free energy difference between the new and old phases, 2) Primary recrystallization is driven by stored energy from deformation, and 3) Secondary recrystallization is driven by interfacial energy reduction. Option A reverses recrystallization and primary recrystallization drivers, exploiting confusion between these similar processes. Option B incorrectly assigns interfacial energy as the main driver for recrystallization, a common misconception. Option D reverses primary and secondary recrystallization drivers, capitalizing on their sequential relationship.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3393, "question": "Briefly describe the alloying principle of stainless steel.", "answer": "Alloying principle: Adding alloying elements to form a stable, dense, and strong protective film on the surface of the steel, obtaining a single-phase structure in the steel, and increasing the electrode potential of the solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述不锈钢的合金化原理，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目考查不锈钢合金化原理的基本概念记忆和理解，涉及合金元素的作用和形成保护膜的基本原理，属于基础概念层次。 | 难度: 在选择题型中，该题目要求考生理解并描述不锈钢的合金化原理，涉及基础概念的记忆和简单解释。虽然需要掌握一定的专业术语和基本原理，但不需要复杂的分析或比较，属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "Adding alloying elements to form a stable, dense, and strong protective film on the surface of the steel, obtaining a single-phase structure in the steel, and increasing the electrode potential of the solid solution.", "choice_question": "Which of the following best describes the alloying principle of stainless steel?", "conversion_reason": "The answer is a standard description of the alloying principle of stainless steel, which can be converted into a multiple-choice question format by presenting it as the correct option among several plausible but incorrect alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Adding alloying elements to form a stable, dense, and strong protective film on the surface of the steel, obtaining a single-phase structure in the steel, and increasing the electrode potential of the solid solution", "B": "Introducing alloying elements that preferentially oxidize to create a porous oxide layer that sacrificially protects the underlying steel", "C": "Incorporating alloying elements that increase the hardness through precipitation hardening while maintaining ductility via grain boundary engineering", "D": "Using alloying elements that lower the melting point to facilitate easier processing while maintaining strength through rapid solidification" }, "correct_answer": "A", "explanation": "The correct answer A describes the three key principles of stainless steel alloying: passive film formation, single-phase structure, and electrode potential enhancement. Option B is a cognitive bias trap - while oxidation is involved, the protective film must be dense, not porous. Option C is a professional intuition trap - precipitation hardening is used in some stainless steels but not the fundamental alloying principle. Option D is a multi-level verification trap - processing considerations are secondary to corrosion resistance in stainless steel design.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2788, "question": "Given the initial carbon concentration of plain carbon steel w0=0.85%, after heating to 900°C and holding in air for 1h, the outer carbon concentration drops to zero. If the required carbon concentration in the outer layer of the part is 0.8%, how much depth should be turned off the surface? (D=1.1×10−7cm2/s)", "answer": "From w=w0erf(β), we get 0.80=0.85erf(x/(2√Dt)) → erf(x/(2√Dt))=0.94. Checking the error function table gives x/(2√Dt)=1.33. Calculating √Dt=√(1.1×10−7×3600)=0.0199 cm. Solving for x gives x=1.33×2×0.0199=0.053 cm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及碳浓度的变化和误差函数的查表计算，最终需要求解深度x的值。答案展示了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算（误差函数表查询、扩散方程应用、数值计算）和概念关联（扩散系数与时间的关系），需要综合分析能力，但不需要复杂的推理或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程和误差函数的概念，进行多步骤计算，并查阅误差函数表获取关键参数。虽然题目提供了公式和计算步骤，但需要综合应用多个知识点才能正确解答。", "convertible": true, "correct_option": "0.053 cm", "choice_question": "Given the initial carbon concentration of plain carbon steel w0=0.85%, after heating to 900°C and holding in air for 1h, the outer carbon concentration drops to zero. If the required carbon concentration in the outer layer of the part is 0.8%, how much depth should be turned off the surface? (D=1.1×10−7cm2/s)", "conversion_reason": "The calculation yields a specific numerical answer (0.053 cm), which can be presented as one of the options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.053 cm", "B": "0.042 cm", "C": "0.067 cm", "D": "0.035 cm" }, "correct_answer": "A", "explanation": "The correct answer is calculated using Fick's second law of diffusion, considering the initial carbon concentration (0.85%), surface concentration (0%), desired concentration (0.8%), diffusion coefficient (1.1×10−7 cm2/s), and time (1h). Option B is designed to exploit the common mistake of using a linear approximation instead of the error function solution. Option C targets the error of using the diffusion distance formula without considering concentration gradients. Option D is based on incorrect unit conversion from mm to cm, playing on the cognitive bias of unit confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2702, "question": "Calculate the actual packing density of α-Fe (given that for every 200 iron atoms there is 1 H atom, rFe=0.1241nm, rH=0.036nm, a=0.286nm)", "answer": "K actual=8/3×π×(rFe³+rH³/200)/a³=8/3×π×((0.1241)³+(0.036)³/200)/(0.286)³=0.6845", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过具体计算得出的数值结果 | 知识层次: 题目需要进行多步计算，包括原子半径的立方计算、比例换算以及最终的体积分数计算，涉及多个概念的综合应用和公式的灵活运用，但不需要复杂的推理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、原子半径、堆积密度等多个概念，并进行多步计算。题目要求考生不仅掌握基本公式，还需要正确代入多个变量（铁原子半径、氢原子半径、晶格常数等），并进行综合运算。虽然题目提供了所有必要参数，但计算步骤较多且需要精确处理小量（氢原子占比1/200），在选择题型中属于需要较高计算精度和概念整合能力的题目。", "convertible": true, "correct_option": "0.6845", "choice_question": "Calculate the actual packing density of α-Fe (given that for every 200 iron atoms there is 1 H atom, rFe=0.1241nm, rH=0.036nm, a=0.286nm):", "conversion_reason": "The calculation problem has a definite numerical answer, making it suitable for conversion into a multiple-choice question format where the correct option is the calculated value.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.6845", "B": "0.7231", "C": "0.6982", "D": "0.7124" }, "correct_answer": "A", "explanation": "正确答案A考虑了氢原子对BCC结构的影响，正确计算了实际填充率。B是纯铁的理论填充率，忽略了氢原子影响；C错误地将氢原子半径按铁原子半径计算；D错误地使用了FCC结构的填充率计算方式。干扰项利用了材料科学中常见的晶体结构填充率混淆和杂质原子影响低估的认知偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3272, "question": "What are the main characteristics of diffusion-type phase transformations?", "answer": "The fundamental characteristics of diffusion-type phase transformations are: $\\textcircled{1}$ Atomic diffusion occurs during the phase transformation, and the transformation rate is controlled by diffusion, i.e., determined by the diffusion speed. $\\textcircled{2}$ In alloy phase transformations, the compositions of the new phase and the parent phase are often different. $\\textcircled{3}$ There is only volume change caused by the difference in specific volume between the new phase and the parent phase, with no shape alteration. Phase transformations such as allotropic transformation in pure metals, polymorphic transformation in solid solutions, precipitation transformation, eutectoid transformation, spinodal decomposition, and ordering transformation all belong to diffusion-type phase transformations.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求解释扩散型相变的主要特征，答案提供了详细的文字解释和论述，符合简答题的特点。 | 知识层次: 题目考查扩散型相变的基本特征，属于基础概念的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题中属于较高难度，题目要求掌握扩散型相变的基本特征，并理解多个相关概念（如原子扩散、相变速率控制、新相与母相成分差异、体积变化等）。此外，还需要将这些概念整合成一个完整的体系进行阐述，涉及的知识点较多且需要深入理解。", "convertible": true, "correct_option": "The fundamental characteristics of diffusion-type phase transformations are: ① Atomic diffusion occurs during the phase transformation, and the transformation rate is controlled by diffusion, i.e., determined by the diffusion speed. ② In alloy phase transformations, the compositions of the new phase and the parent phase are often different. ③ There is only volume change caused by the difference in specific volume between the new phase and the parent phase, with no shape alteration. Phase transformations such as allotropic transformation in pure metals, polymorphic transformation in solid solutions, precipitation transformation, eutectoid transformation, spinodal decomposition, and ordering transformation all belong to diffusion-type phase transformations.", "choice_question": "Which of the following best describes the main characteristics of diffusion-type phase transformations?", "conversion_reason": "The answer is a standard description of the characteristics of diffusion-type phase transformations, which can be converted into a multiple-choice question format by presenting the answer as one of the options and asking the examinee to select the correct description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Atomic diffusion occurs with composition changes, but the transformation rate is primarily controlled by interfacial energy rather than diffusion speed", "B": "Atomic diffusion occurs during transformation with composition changes, and the rate is diffusion-controlled, but significant shape changes accompany the volume changes", "C": "No atomic diffusion occurs, but the transformation shows composition changes due to spinodal decomposition mechanisms", "D": "Atomic diffusion occurs with composition changes, rate is diffusion-controlled, and only volume changes occur without shape alteration" }, "correct_answer": "D", "explanation": "The correct answer D accurately describes all three key characteristics of diffusion-type transformations: 1) diffusion-controlled rate, 2) possible composition changes, and 3) only volume changes. Option A incorrectly states interfacial energy controls the rate. Option B wrongly includes shape changes. Option C is completely wrong by denying diffusion while mentioning spinodal decomposition, which actually requires diffusion. These options exploit common misconceptions about what controls transformation kinetics (A), confusion between diffusionless and diffusion transformations (C), and incorrect assumptions about microstructural changes (B).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4470, "question": "Why is it so important to control the rate of drying of a ceramic body that has been hydroplastically formed or slip cast?", "answer": "It is important to control the rate of drying inasmuch as if the rate of drying is too rapid, there will be nonuniform shrinkage between surface and interior regions, such that warping and/or cracking of the ceramic ware may result.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么控制陶瓷体的干燥速率很重要，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目需要理解陶瓷干燥过程中的非均匀收缩现象及其后果，涉及多个概念的关联（干燥速率、收缩、变形/开裂）和综合分析（表面与内部区域的差异），但不需要复杂的机理推导或创新设计。 | 难度: 在选择题中属于中等难度，需要理解陶瓷干燥过程中的收缩不均匀性及其导致的变形和开裂问题，并进行概念关联和综合分析。虽然不涉及多步计算，但需要对材料行为有较深入的理解。", "convertible": true, "correct_option": "It is important to control the rate of drying inasmuch as if the rate of drying is too rapid, there will be nonuniform shrinkage between surface and interior regions, such that warping and/or cracking of the ceramic ware may result.", "choice_question": "Why is it so important to control the rate of drying of a ceramic body that has been hydroplastically formed or slip cast?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options and other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To prevent differential shrinkage between surface and interior regions that could lead to warping/cracking", "B": "To ensure complete evaporation of all chemically bonded water molecules before firing", "C": "To maintain the optimal viscosity for subsequent glaze application processes", "D": "To allow sufficient time for crystalline phase transformations to occur uniformly" }, "correct_answer": "A", "explanation": "Correct answer A addresses the fundamental issue of non-uniform drying stresses. Distractors: B exploits confusion between physically and chemically bonded water (chemically bonded water only leaves during firing). C misdirects to a downstream process concern. D introduces an irrelevant phase transformation concept that doesn't occur during drying.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 393, "question": "Common strengthening methods for metallic materials include (17), (18), (19), and (20).", "answer": "(17) Solid solution strengthening; (18) Grain refinement strengthening; (19) Second phase strengthening; (20) Work hardening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的强化方法名称，需要文字回答而非选择或判断，也不涉及计算过程 | 知识层次: 题目考查对金属材料常见强化方法的基本概念记忆，属于基础概念和分类的范畴，不需要复杂的分析或综合应用。 | 难度: 该题目属于基础概念记忆类型，仅需要考生回忆并识别金属材料的常见强化方法。题目提供了明确的正确选项，考生只需匹配记忆中的知识点即可完成作答，无需进行复杂的概念解释或体系阐述。在选择题型中，这种直接考察定义和分类的记忆性题目属于最低难度等级。", "convertible": true, "correct_option": "Solid solution strengthening; Grain refinement strengthening; Second phase strengthening; Work hardening", "choice_question": "Which of the following are common strengthening methods for metallic materials?", "conversion_reason": "The answer is a list of standard terms or concepts, which can be converted into a multiple-choice question format by presenting these terms as options and asking the student to identify the correct ones.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening", "B": "Elastic modulus enhancement", "C": "Thermal conductivity improvement", "D": "Magnetic domain alignment" }, "correct_answer": "A", "explanation": "Solid solution strengthening (A) is a fundamental strengthening mechanism where solute atoms distort the crystal lattice, impeding dislocation motion. Elastic modulus enhancement (B) is a cognitive bias trap - while modulus is important, it's an intrinsic property not a strengthening method. Thermal conductivity improvement (C) exploits material property confusion, as conductivity relates to heat transfer not mechanical strength. Magnetic domain alignment (D) is a specialist intuition trap, using a real phenomenon from ferromagnetic materials that doesn't directly strengthen the lattice.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3770, "question": "A 2 in. × 8 in. × 10 in. iron casting is produced and, after cooling to room temperature, is found to weigh 43.9 lb. Determine the percent shrinkage that must have occurred during solidification.", "answer": "The percent shrinkage that must have occurred during solidification is 3.4%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算（计算收缩百分比）并应用相关公式，答案是一个具体的数值结果（3.4%），符合计算题的特征。 | 知识层次: 题目涉及基本的数值计算和公式应用，需要计算铁铸件的体积和密度，然后应用简单的百分比公式来确定收缩率。虽然需要一定的理解和计算能力，但整个过程是直接的，不需要多步计算或复杂的概念关联。 | 难度: 在选择题中属于简单应用难度，需要应用基本公式（密度计算和百分比变化）并进行简单计算，但不需要多个公式组合或复杂分析。", "convertible": true, "correct_option": "3.4%", "choice_question": "A 2 in. × 8 in. × 10 in. iron casting is produced and, after cooling to room temperature, is found to weigh 43.9 lb. The percent shrinkage that must have occurred during solidification is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.4%", "B": "6.8%", "C": "1.7%", "D": "5.1%" }, "correct_answer": "A", "explanation": "正确答案是3.4%，这是通过计算铁铸件的理论密度与实际测量重量之间的差异得出的。干扰项B（6.8%）利用了常见的认知偏差，即直接翻倍正确答案的数值。干扰项C（1.7%）则是将正确答案减半，利用了直觉上认为收缩率应该更小的错误判断。干扰项D（5.1%）设计为接近但略高于正确答案的数值，利用了专业直觉中可能高估收缩率的陷阱。这些干扰项都针对了AI模型在处理数值计算时可能产生的不同层面的直觉错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2425, "question": "Calculate the diffusion rate of AI through Al2O3 at a temperature 10 times that at 1000°C (i.e., find D(T)=10D(1000°C)). The activation energy Q for AI diffusion in Al2O3 crystal is known to be 477 kJ/mol.", "answer": "According to the relationship between diffusion coefficient and temperature D = D0 exp(-Q/RT), let T1=1000°C=1273K, and find the temperature T2 where D(T2)=10D(T1). From 10 = exp(-Q/R (1/T2 - 1/T1)), we get 1/T2 = 1/T1 - (R ln10)/Q = 1/1273K - (8.314*ln10)/477000 = 7.454×10^-4 K^-1. Therefore, T2=1341.6K, and the temperature increases by 68.6K.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解扩散速率，答案中包含了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和公式应用，需要理解扩散系数与温度的关系，并运用对数运算求解温度变化。虽然不涉及复杂的综合分析或创新应用，但超出了简单直接套用公式的层次。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散系数与温度的关系公式，并进行多步骤的计算和转换。题目要求考生能够正确应用阿伦尼乌斯方程，进行对数运算和温度单位的转换，同时需要处理较大的数值计算（如477 kJ/mol的激活能）。虽然题目提供了明确的公式指引，但计算步骤较为复杂，涉及多个关键概念的综合运用，属于综合性计算问题。", "convertible": true, "correct_option": "68.6K", "choice_question": "Calculate the temperature increase needed for the diffusion rate of AI through Al2O3 to be 10 times that at 1000°C, given the activation energy Q is 477 kJ/mol.", "conversion_reason": "The calculation leads to a specific numerical answer (68.6K), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "68.6K", "B": "100K", "C": "477K", "D": "10K" }, "correct_answer": "A", "explanation": "正确答案A(68.6K)通过阿伦尼乌斯方程计算得出，考虑了温度对扩散系数的指数影响。干扰项B(100K)利用直觉上认为10倍速率需要100K温升的认知偏差。干扰项C(477K)直接使用激活能量值制造专业直觉陷阱。干扰项D(10K)通过极低数值诱导对温度影响程度的低估。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 653, "question": "Describe the main strengthening mechanisms that can be employed for industrial pure aluminum", "answer": "The main strengthening mechanisms for industrial pure aluminum are work hardening and grain refinement strengthening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求描述工业纯铝的主要强化机制，需要文字解释和论述，答案也是以文字形式呈现的简要说明。 | 知识层次: 题目考查对工业纯铝主要强化机制的基础概念记忆和理解，涉及简单的分类和基本原理，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求描述强化机制，但在选择题的上下文中，正确选项已经提供了明确的答案（加工硬化和晶粒细化强化）。这需要考生对工业纯铝的基本强化机制有概念性的理解和记忆，但不需要进行复杂的分析或比较。题目考察的是对基础概念的掌握程度，属于\"概念解释和描述\"层次的知识。", "convertible": true, "correct_option": "work hardening and grain refinement strengthening", "choice_question": "Which of the following are the main strengthening mechanisms that can be employed for industrial pure aluminum?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Work hardening and grain refinement strengthening", "B": "Solid solution strengthening and precipitation hardening", "C": "Dispersion strengthening and twinning-induced plasticity", "D": "Martensitic transformation and dislocation pinning" }, "correct_answer": "A", "explanation": "The correct answer is A because industrial pure aluminum lacks sufficient alloying elements for solid solution or precipitation strengthening (B), does not form stable dispersoids (C), and cannot undergo martensitic transformation (D). Work hardening and grain refinement are the only universally applicable mechanisms for pure metals. Option B exploits the common misconception that all strengthening mechanisms apply equally to pure metals and alloys. Option C uses a plausible-sounding but inapplicable mechanism from advanced alloys. Option D introduces metallurgical concepts that are irrelevant to pure aluminum systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4146, "question": "Which of the following characteristics are displayed by hard magnetic materials in terms of hysteresis loop size?", "answer": "Hard materials have relatively large hysteresis loops.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释硬磁材料在磁滞回线尺寸方面表现出的特性，需要文字解释和论述，而不是从选项中选择或简单判断对错。 | 知识层次: 题目考查硬磁材料的基本特性（磁滞回线大小）的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对硬磁材料基本特性的记忆，属于最基础的定义简答。题目直接询问硬磁材料磁滞回线的特征，正确选项明确给出了定义性描述，不需要任何解释或分析步骤。这符合等级1\"基本定义简答\"的标准，是选择题型中最简单的类型。", "convertible": true, "correct_option": "Hard materials have relatively large hysteresis loops.", "choice_question": "Which of the following characteristics are displayed by hard magnetic materials in terms of hysteresis loop size?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question by presenting the answer as one of the options. The answer is a standard description of the characteristic of hard magnetic materials, making it suitable for conversion.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Exhibit large hysteresis loops with high coercivity", "B": "Show narrow hysteresis loops similar to soft magnetic materials", "C": "Display zero hysteresis due to perfect domain alignment", "D": "Demonstrate reversible hysteresis loops under alternating fields" }, "correct_answer": "A", "explanation": "Correct answer A reflects the fundamental property of hard magnetic materials having large hysteresis loops with high coercivity, requiring significant energy to demagnetize. Option B exploits the common confusion between hard and soft magnetic materials. Option C creates a trap by suggesting an idealized scenario that doesn't exist in real materials. Option D introduces a plausible-sounding but incorrect concept of reversibility in hard magnets.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3372, "question": "What are the ways to improve the strength and toughness of mild steel?", "answer": "The way to improve is solid solution strengthening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述提高低碳钢强度和韧性的方法，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释和论述提高低碳钢强度和韧性的方法，涉及多个概念（如固溶强化）的关联和综合分析，需要多步思维过程来理解和应用这些概念。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及的知识点（固溶强化）属于中等应用层次，需要考生将材料强化机制与具体材料（低碳钢）的性能改善方法进行关联。虽然不涉及多步计算，但要求考生在选项分析时能综合判断不同强化方式的适用性，符合等级3的综合分析要求。", "convertible": true, "correct_option": "solid solution strengthening", "choice_question": "Which of the following is a way to improve the strength and toughness of mild steel?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening with interstitial carbon atoms", "B": "Increasing the elastic modulus through cold working", "C": "Precipitation hardening by adding copper to the alloy", "D": "Reducing dislocation density through annealing" }, "correct_answer": "A", "explanation": "Correct answer A utilizes interstitial solid solution strengthening, which is effective for mild steel. B is incorrect because elastic modulus is an intrinsic property and cannot be significantly altered by cold working. C is a trap as precipitation hardening requires specific alloying elements like copper, which mild steel lacks. D is misleading because while annealing reduces dislocation density, it actually decreases strength while improving ductility.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4746, "question": "A cylindrical rod of steel (E=207 \\mathrm{GPa}, 30 × 10^{6} psi) having a yield strength of 310 MPa(45,000 psi) is to be subjected to a load of 11,100N(2500 lb). If the length of the rod is 500 mm(20.0 in.), what must be the diameter to allow an elongation of 0.38 mm(0.015 in.)?", "answer": "the diameter must be 9.5 mm (0.376 in.).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定圆柱形钢棒的直径。解答过程涉及弹性模量、载荷和伸长量等参数的计算，最终得出具体的直径数值。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即胡克定律和应力应变关系的直接套用，无需多步计算或综合分析。 | 难度: 在选择题中属于简单公式应用计算难度。题目要求直接应用胡克定律和圆柱体横截面积公式，步骤较为直接，只需进行简单代数运算即可得出答案。虽然涉及单位转换，但在选择题型中，这些步骤被简化，因为正确选项已经给出，减少了计算错误的可能性。", "convertible": true, "correct_option": "9.5 mm (0.376 in.)", "choice_question": "A cylindrical rod of steel (E=207 GPa, 30 × 10^6 psi) having a yield strength of 310 MPa (45,000 psi) is to be subjected to a load of 11,100 N (2500 lb). If the length of the rod is 500 mm (20.0 in.), what must be the diameter to allow an elongation of 0.38 mm (0.015 in.)?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "9.5 mm (0.376 in.)", "B": "7.2 mm (0.283 in.)", "C": "12.1 mm (0.476 in.)", "D": "5.8 mm (0.228 in.)" }, "correct_answer": "A", "explanation": "正确答案A通过弹性变形公式ΔL=FL/AE计算得出，其中A=πd²/4。干扰项B错误地使用了剪切模量公式计算。干扰项C基于错误假设认为需要考虑屈服强度限制。干扰项D错误地将单位从英寸直接转换为毫米而未重新计算。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4355, "question": "If copper (which has a melting point of 1085^{\\circ} C ) homogeneously nucleates at 849^{\\circ} C, calculate the critical radius given values of -1.77 × 10^{9} J/ m^{3} and 0.200 J/ m^{2}, respectively, for the latent heat of fusion and the surface free energy.", "answer": "1.30 nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解临界半径，答案是一个具体的数值结果（1.30 nm），这符合计算题的特征。 | 知识层次: 题目需要应用临界半径计算公式，涉及多步计算和概念关联（如熔化热、表面自由能等），但不需要复杂的综合分析或推理。 | 难度: 在选择题中属于中等偏上难度，需要理解临界半径计算公式（涉及表面自由能、过冷度、潜热等概念），并进行多步单位换算和数值计算。虽然题目提供了所有必要参数，但需要正确应用公式并处理负号问题（-1.77×10^9 J/m³表示放热过程），最终得到纳米级结果。相比简单概念题或单步计算题更复杂，但比需要推导公式或处理多变量的题目更直接。", "convertible": true, "correct_option": "1.30 nm", "choice_question": "If copper (which has a melting point of 1085°C) homogeneously nucleates at 849°C, what is the critical radius given values of -1.77 × 10^9 J/m^3 and 0.200 J/m^2, respectively, for the latent heat of fusion and the surface free energy?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.30 nm", "B": "2.15 nm", "C": "0.85 nm", "D": "1.77 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (1.30 nm) calculated using the critical radius formula r* = 2γTm/(ΔHfΔT). Option B (2.15 nm) is designed to exploit cognitive bias by using the surface energy value (0.200 J/m²) directly. Option C (0.85 nm) traps those who confuse melting point with nucleation temperature. Option D (1.77 nm) is a multi-level trap using the latent heat value (-1.77×10⁹ J/m³) to trigger false pattern recognition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3562, "question": "The packing density of a simple cubic crystal is ( ). \\n\\nA. $100\\\\%$ B.65% C.52% D.58%", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项（A、B、C、D）中选择正确答案，符合选择题的特征。 | 知识层次: 题目考查简单立方晶体堆积密度的基本概念记忆，属于晶体结构的基础知识，不需要复杂的计算或分析。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆简单立方晶体的堆积密度数值即可作答，无需进行概念辨析或复杂计算。", "convertible": true, "correct_option": "52%", "choice_question": "The packing density of a simple cubic crystal is ( ).", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "68%", "B": "74%", "C": "52%", "D": "64%" }, "correct_answer": "C", "explanation": "The correct packing density for a simple cubic crystal is 52% (option C), calculated as the volume occupied by atoms divided by the total unit cell volume. Option A (68%) mimics the face-centered cubic packing density, exploiting confusion between crystal structures. Option B (74%) represents hexagonal close packing, a common reference point that may trigger incorrect recall. Option D (64%) approximates body-centered cubic packing, creating numerical proximity confusion. These distractors leverage material scientists' familiarity with other packing arrangements to induce errors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 336, "question": "What is the main difference between recrystallization and solid-state phase transformation?", "answer": "Recrystallization is only a microstructural change without structural change, and the driving force is deformation stored energy; solid-state phase transformation is a structural change between solid/solid phases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述两个概念之间的主要区别，答案以文字形式详细说明了两者的不同点，没有涉及选择、判断或计算。 | 知识层次: 题目考查对再结晶和固态相变这两个基本概念的定义和区别的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个基础概念（再结晶和固态相变），但正确选项要求考生能够区分两者的关键差异（微观结构变化vs结构变化，驱动力来源）。这需要考生不仅记住定义，还要理解概念之间的对比关系，属于概念解释和描述层次的认知要求。但题目并未涉及复杂机制或多步骤分析，因此不属于最高难度等级。", "convertible": true, "correct_option": "Recrystallization is only a microstructural change without structural change, and the driving force is deformation stored energy; solid-state phase transformation is a structural change between solid/solid phases.", "choice_question": "What is the main difference between recrystallization and solid-state phase transformation?", "conversion_reason": "The answer is a standard and concise explanation of the difference between the two processes, making it suitable for conversion into a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization involves nucleation and growth of new grains with reduced dislocation density, while phase transformation requires overcoming an activation energy barrier for atomic rearrangement", "B": "Both processes result in new crystal structures, but recrystallization is driven by temperature while phase transformation is driven by pressure", "C": "Recrystallization only occurs in single-phase materials, whereas phase transformation requires multiphase systems", "D": "The key difference is that recrystallization preserves the original crystal structure while phase transformation changes it" }, "correct_answer": "D", "explanation": "Correct answer D precisely captures the fundamental distinction: recrystallization is a structural restoration process (same crystal structure), while phase transformation alters the crystal structure. Option A describes mechanisms rather than the core difference. Option B is incorrect as both processes can be temperature-driven and recrystallization doesn't change structure. Option C is wrong because recrystallization can occur in multiphase materials. The distractors exploit common misconceptions about driving forces (B) and system requirements (C), while A's technical accuracy about mechanisms may mislead systems to overlook the simpler structural distinction.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4328, "question": "What is the proeutectoid phase for an iron-carbon alloy in which the mass fractions of total ferrite and total cementite are 0.92 and 0.08 , respectively? Why?", "answer": "the proeutectoid phase is \\alpha ferrite because the alloy composition c_{0} is less than 0.76 wt% C.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么在给定的铁碳合金中先共析相是α铁素体，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要理解铁碳合金相图的基本概念，并能够根据给定的质量分数计算合金成分，进而判断先共析相。这涉及到多步计算和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握铁碳合金中的先共析相概念，并能根据给定的质量分数计算合金成分，进而判断先共析相的类型。这需要考生具备一定的计算能力和对相图的理解，但题目提供了足够的信息来推导出正确答案，因此难度适中。", "convertible": true, "correct_option": "the proeutectoid phase is α ferrite because the alloy composition c_{0} is less than 0.76 wt% C", "choice_question": "What is the proeutectoid phase for an iron-carbon alloy in which the mass fractions of total ferrite and total cementite are 0.92 and 0.08, respectively?", "conversion_reason": "The answer is a standard terminology and explanation, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "α ferrite (0.65 wt% C)", "B": "Cementite (6.7 wt% C)", "C": "Pearlite (0.76 wt% C)", "D": "Austenite (1.2 wt% C)" }, "correct_answer": "A", "explanation": "The correct answer is A because the alloy composition (calculated from given mass fractions) is hypoeutectoid (0.65 wt% C < 0.76 wt% C), making α ferrite the proeutectoid phase. Option B is wrong but tempting as cementite is present but not the proeutectoid phase. Option C exploits confusion between eutectoid composition and proeutectoid phase. Option D uses a common misconception that austenite can be proeutectoid in slow cooling conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 81, "question": "Explain the meaning of the symbol V_{Cl}^*", "answer": "Chlorine ion vacancy, with a single positive charge", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释符号V_{Cl}^*的含义，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对缺陷化学符号的基本概念的记忆和理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目仅要求识别和记忆基础符号的定义（氯离子空位带一个正电荷），属于最基础的概念记忆层次。不需要解释或分析，只需直接回忆符号对应的定义即可，因此属于等级1的简单难度。", "convertible": true, "correct_option": "Chlorine ion vacancy, with a single positive charge", "choice_question": "What is the meaning of the symbol V_{Cl}^*?", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by providing options including the correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chlorine ion vacancy with a single positive charge", "B": "Chlorine interstitial with a single negative charge", "C": "Chlorine vacancy-electron complex", "D": "Neutral chlorine vacancy" }, "correct_answer": "A", "explanation": "The correct answer is A because the Kröger-Vink notation V_{Cl}^* specifically denotes a chlorine ion vacancy (V) with a single positive effective charge (*). Option B incorrectly describes an interstitial defect with wrong charge. Option C introduces an unnecessary electron complex not indicated by the notation. Option D misses the critical charge designation which is explicitly shown by the * symbol.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1837, "question": "What is the relationship between the diffusion coefficient of intrinsic diffusion and temperature?", "answer": "D=D0exp(-(ΔHf/2 + ΔHm)/RT)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释扩散系数与温度之间的关系，答案给出了具体的数学表达式，属于需要文字解释和论述的简答题类型 | 知识层次: 题目要求解释扩散系数与温度的关系，并给出具体的公式。这需要理解扩散机制（ΔHf和ΔHm的含义）以及阿伦尼乌斯方程的应用，属于多步概念关联和综合分析。虽然不涉及复杂的推理或创新，但超出了简单记忆或直接套用公式的层次。 | 难度: 在选择题中属于较高难度，需要理解扩散系数与温度的关系，并掌握阿伦尼乌斯方程的应用。题目涉及多个概念（ΔHf、ΔHm、R、T）的综合分析，以及多步计算（指数运算和参数组合）。此外，需要将扩散机制与热力学参数关联起来，这在选择题型中属于较复杂的综合分析要求。", "convertible": true, "correct_option": "D=D0exp(-(ΔHf/2 + ΔHm)/RT)", "choice_question": "What is the relationship between the diffusion coefficient of intrinsic diffusion and temperature?", "conversion_reason": "The answer is a standard formula, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "D=D0exp(-(ΔHf/2 + ΔHm)/RT)", "B": "D=D0exp(-ΔHm/RT)", "C": "D=D0exp(-ΔHf/RT)", "D": "D=D0exp(-(ΔHf + ΔHm)/RT)" }, "correct_answer": "A", "explanation": "正确答案A正确反映了本征扩散中同时考虑空位形成能(ΔHf)和迁移能(ΔHm)的物理本质。干扰项B仅考虑迁移能，是自扩散的常见表达式；干扰项C仅考虑空位形成能，是空位浓度的表达式；干扰项D错误地将两种能量简单相加，忽略了本征扩散中空位形成能只需一半的物理机制。这些干扰项利用了对扩散机制理解不完整时容易产生的直觉错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1215, "question": "Why is carburization chosen in γ-Fe around 930‰, where the diffusion coefficient increases with carbon content?", "answer": "In γ-Fe, the diffusion coefficient increases with carbon content", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么在γ-Fe中930‰温度下选择渗碳处理，并说明扩散系数随碳含量增加的原因。答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求解释为什么在γ-Fe中碳含量增加时扩散系数增加，并选择930‰作为渗碳温度。这需要深入理解扩散机制、碳在γ-Fe中的行为以及温度对扩散的影响，涉及多个概念的关联和综合分析。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "In γ-Fe, the diffusion coefficient increases with carbon content", "choice_question": "Why is carburization chosen in γ-Fe around 930‰, where the diffusion coefficient increases with carbon content?", "conversion_reason": "The answer is a standard statement that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The increasing carbon content reduces the activation energy for diffusion in γ-Fe", "B": "Higher carbon concentration creates more vacancies that enhance diffusion", "C": "Carbon atoms preferentially occupy interstitial sites that lower the energy barrier", "D": "The austenite phase has higher solubility limit for carbon than ferrite" }, "correct_answer": "A", "explanation": { "correct_answer": "The increasing carbon content reduces the activation energy for diffusion in γ-Fe. This is the fundamental reason why diffusion coefficient increases with carbon content in austenite.", "distractors": { "B": "This is a vacancy-mediated diffusion mechanism that applies to substitutional diffusion, not interstitial carbon diffusion in γ-Fe.", "C": "While carbon does occupy interstitial sites, this statement incorrectly describes the mechanism for increased diffusion coefficient.", "D": "Although true, this is unrelated to the phenomenon of increasing diffusion coefficient with carbon content." }, "cognitive_traps": { "vacancy_trap": "Using vacancy mechanism which is correct for self-diffusion but wrong for interstitial diffusion", "site_occupancy_trap": "Mixing correct fact (interstitial sites) with incorrect mechanism", "solubility_distraction": "Introducing a true but irrelevant fact about phase solubility" } }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2057, "question": "Given the melting point of Cu tm=1083°C, latent heat of fusion Lm=1.88×10^3 J/cm^3, and specific surface energy σ=1.44×10^5 J/cm^2. Calculate the critical nucleus radius for homogeneous nucleation of Cu at 853°C.", "answer": "rk=9.03×10^-10 m", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的物理参数（熔点、潜热、比表面能）和公式计算临界核半径，答案是一个具体的数值结果，解答过程需要数值计算和公式应用。 | 知识层次: 题目需要应用均质形核的临界半径公式，涉及多步计算（包括温度转换、单位统一等），并需要理解表面能、潜热等概念之间的关联。虽然不涉及复杂的机理分析或创新设计，但已超出简单套用公式的范畴，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念（临界核半径、熔化潜热、比表面能等）并进行多步计算（包括温度转换、公式代入等）。虽然题目提供了所有必要参数，但解题过程涉及多个物理概念的关联和综合应用，属于综合性计算问题。", "convertible": true, "correct_option": "9.03×10^-10 m", "choice_question": "Given the melting point of Cu tm=1083°C, latent heat of fusion Lm=1.88×10^3 J/cm^3, and specific surface energy σ=1.44×10^5 J/cm^2. The critical nucleus radius for homogeneous nucleation of Cu at 853°C is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "9.03×10^-10 m", "B": "1.44×10^-9 m", "C": "1.88×10^-9 m", "D": "2.16×10^-9 m" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算临界核半径公式 r* = 2σTm/(LmΔT) 得到的结果。干扰项B直接使用了表面能σ的数值但错误地将其作为半径。干扰项C使用了潜热Lm的数值但忽略了单位转换。干扰项D则是将熔点Tm数值错误地代入计算。这些干扰项都利用了材料参数数值的直接视觉关联性来制造认知陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1468, "question": "A screw dislocation line can only undergo glide motion, not climb motion.", "answer": "Correct", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（A screw dislocation line can only undergo glide motion, not climb motion），要求判断其正确性（Correct），这是典型的判断题特征。 | 知识层次: 题目考查对位错运动方式（滑移和攀移）的基本概念记忆和理解，属于材料科学中位错理论的基础知识点。 | 难度: 该题目属于基础概念正误判断题，仅需记忆螺丝位错线的基本运动特性（滑移与攀移的区别），无需深入理解或分析多个概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "Correct", "choice_question": "A screw dislocation line can only undergo glide motion, not climb motion.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all crystalline materials, the Burgers vector of a perfect dislocation must be equal to the shortest lattice translation vector.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the Burgers vector of a perfect dislocation is often the shortest lattice translation vector in simple crystals, this is not universally true for all crystalline materials. In complex crystal structures or ordered intermetallics, the Burgers vector may correspond to a longer lattice translation vector that maintains the crystal's stoichiometry and order. This statement is a precise trap using 'must be equal' which is overly absolute.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4499, "question": "For the following pairs of polymers, do the following: (1) state whether or not it is possible to determine whether one polymer is more likely to crystallize than the other; (2) if it is possible, note which is the more likely and then cite reason(s) for your choice; and (3) if it is not possible to decide, then state why. (d) Alternating poly(styrene-ethylene) copolymer; random poly(vinyl chloride-tetrafluoroethylene) copolymer.", "answer": "Yes, it is possible to decide for these two copolymers. The alternating poly(styrene-ethylene) copolymer is more likely to crystallize. Alternating copolymers crystallize more easily than do random copolymers.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对两种聚合物的结晶可能性进行比较，并给出理由。答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目要求学生理解并应用聚合物结晶性的基本原理，比较两种不同结构共聚物的结晶能力。需要分析交替共聚物和无规共聚物的结构差异对结晶性的影响，并给出合理的解释。这涉及到多个概念的关联和综合分析，但不需要进行复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生能够区分交替共聚物和随机共聚物的结晶能力，并基于聚合物结构特征做出判断。虽然不需要复杂的计算，但需要对聚合物结晶原理和共聚物类型有较深入的理解，并能将两者关联起来进行综合分析。", "convertible": true, "correct_option": "The alternating poly(styrene-ethylene) copolymer is more likely to crystallize.", "choice_question": "For the following pairs of polymers, which one is more likely to crystallize: alternating poly(styrene-ethylene) copolymer or random poly(vinyl chloride-tetrafluoroethylene) copolymer?", "conversion_reason": "The original short answer question asks for a comparison between two polymers regarding their likelihood to crystallize, and the answer provides a clear, definitive choice. This can be easily converted into a multiple-choice question format by presenting the two polymers as options and asking which one is more likely to crystallize.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Alternating poly(styrene-ethylene) copolymer due to its regular chain structure allowing better packing", "B": "Random poly(vinyl chloride-tetrafluoroethylene) copolymer because fluoropolymers generally have higher crystallinity", "C": "Both copolymers will crystallize equally due to similar backbone flexibility", "D": "Neither copolymer can crystallize due to their irregular chemical structures" }, "correct_answer": "A", "explanation": "The alternating poly(styrene-ethylene) copolymer is more likely to crystallize because its alternating structure provides regularity that enables chain packing. Option B exploits the common knowledge that fluoropolymers often crystallize well, but ignores the disruptive effect of random copolymerization. Option C creates a false equivalence between backbone flexibility and crystallizability. Option D overgeneralizes the concept of irregularity, ignoring that alternating copolymers can achieve sufficient regularity for crystallization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2793, "question": "For pure iron carburized at $950\\\\mathrm{\\\\textperthousand}$, it is desired to achieve a carbon content of $\\\\mathfrak{w}{1}\\\\left(\\\\mathbb{C}\\\\right)=0,9\\\\%$ at a depth of $0.1\\\\mathrm{mm}$. Assuming the surface carbon content remains at $w{2}\\\\left(\\\\mathsf{C}\\\\right)=1.20\\\\%$, and the diffusion coefficient $D_{\\\\mathtt{Y F e}}{=}10^{{-}10}\\\\ensuremath{\\\\mathbf{m}}^{2}/\\\\mathbf{s},$, calculate the minimum carburization time required to meet this requirement.", "answer": "$$\\\\begin{array}{c}{\\\\frac x{2\\\\sqrt{D t}}=0,8163}}\\\\ {{{\\\\mathrm x}=2\\\\times0.8163\\\\times\\\\sqrt{1.1\\\\times10^{-1}\\\\times3600}}}\\\\ {{{\\\\mathrm x}=0.032\\\\mathrm{(cm)}}}\\\\ {{{\\\\mathrm w}_{2}-{\\\\mathrm w}_{1}=\\\\mathrm{erf}\\\\left({\\\\frac{x}{2\\\\sqrt{D t}}}\\\\right)}}\\\\ {{{\\\\mathrm x}_{2}-{\\\\mathrm w}_{0}=\\\\mathrm{erf}\\\\left({\\\\frac{0.1\\\\times10^{-3}}{2\\\\sqrt{10^{-10}\\\\times t}}}\\\\right)}}\\\\end{array}$$ $$\\\\operatorname{erf}{\\\\Big(}{\\\\frac{5}{\\\\sqrt{t}}}{\\\\Big)}=0.25$$ Look up the table to find $$\\\\frac{5}{\\\\sqrt{t}}\\\\approx0.2763,$$ hence $$t\\\\approx327(\\\\mathrm{s})$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解最小渗碳时间，答案中包含了具体的计算步骤和公式应用，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要应用扩散定律和误差函数表进行综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程和误差函数的概念，并进行多步骤计算。题目涉及查找表格数据和解方程，但整体计算过程在选择题型内相对可控，属于综合性计算问题。", "convertible": true, "correct_option": "327(s)", "choice_question": "For pure iron carburized at $950\\mathrm{\\textperthousand}$, it is desired to achieve a carbon content of $\\mathfrak{w}{1}\\left(\\mathbb{C}\\right)=0,9\\%$ at a depth of $0.1\\mathrm{mm}$. Assuming the surface carbon content remains at $w{2}\\left(\\mathsf{C}\\right)=1.20\\%$, and the diffusion coefficient $D_{\\mathtt{Y F e}}{=}10^{{-}10}\\ensuremath{\\mathbf{m}}^{2}/\\mathbf{s},$, calculate the minimum carburization time required to meet this requirement.", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format with the correct option being the calculated time.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "327 s", "B": "654 s", "C": "163.5 s", "D": "81.75 s" }, "correct_answer": "A", "explanation": "正确答案A通过Fick第二定律计算得出，使用误差函数求解扩散时间。干扰项B是正确答案的两倍，利用了计算中可能忽略的平方关系。干扰项C是正确答案的一半，利用了可能错误线性化指数关系的直觉。干扰项D是C的一半，进一步放大线性化错误。这些干扰项专门针对AI可能对扩散方程中指数关系理解不足的弱点设计。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 958, "question": "Briefly describe the critical resolved shear stress for slip", "answer": "The minimum resolved shear stress required to initiate slip system movement; it is a constant value, related to the intrinsic properties of the material and independent of the orientation of external forces.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述临界分切应力的概念，答案是一段文字解释，符合简答题的特征 | 知识层次: 题目考查对临界分切应力这一基本概念的记忆和理解，不涉及复杂计算或综合分析 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并描述临界分切应力的定义及其特性，涉及对材料科学基础概念的掌握。虽然需要一定的记忆和理解，但不需要复杂的分析或比较多个概念，因此属于中等难度。", "convertible": true, "correct_option": "The minimum resolved shear stress required to initiate slip system movement; it is a constant value, related to the intrinsic properties of the material and independent of the orientation of external forces.", "choice_question": "Which of the following best describes the critical resolved shear stress for slip?", "conversion_reason": "The answer is a standard definition of a technical term, which can be presented as a correct option among other plausible but incorrect definitions in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The minimum resolved shear stress required to initiate slip system movement; it is a constant value, related to the intrinsic properties of the material and independent of the orientation of external forces", "B": "The maximum shear stress a material can withstand before fracture, dependent on both crystal orientation and temperature conditions", "C": "The stress required to activate the easiest slip system, which varies with the angle between slip plane and applied stress direction", "D": "The yield strength of a single crystal measured along its most favorable slip direction, equivalent to the macroscopic yield stress" }, "correct_answer": "A", "explanation": "Option A correctly defines CRSS as an intrinsic material property. Option B confuses CRSS with fracture stress by introducing fracture condition. Option C is partially correct but incorrectly suggests orientation dependence. Option D erroneously equates CRSS with macroscopic yield stress, ignoring polycrystalline effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3028, "question": "How to prevent the aging of polymers?", "answer": "Currently, there are three measures taken to prevent aging.\\n① Modify the structure of the polymer. For example, chlorinating polyvinyl chloride can improve its thermal stability.\\n② Add anti-aging agents. Incorporating organic compounds such as salicylate esters, benzophenones, and carbon black into polymers can prevent photo-oxidation.\\n③ Surface treatment. Coating the surface of polymer materials with metals (such as silver, copper, nickel) or spraying anti-aging coatings (such as paint, paraffin) as protective layers isolates the material from air, light, water, and other aging-inducing media to prevent aging.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释如何防止聚合物老化，答案提供了详细的文字解释和论述，包括三种具体措施及其原理，符合简答题的特征。 | 知识层次: 题目要求列举并解释防止聚合物老化的措施，涉及多个知识点的关联和综合分析，需要理解老化机理并应用不同的防护方法，思维过程有一定深度。 | 难度: 在选择题型中，该题目属于较高难度，因为它要求考生不仅理解聚合物老化的基本概念，还需要掌握三种具体的防老化措施及其原理。题目涉及的知识点包括聚合物结构改性、抗老化剂的作用机制以及表面处理技术，这些内容需要考生进行多角度分析和综合应用。此外，正确选项中的详细说明要求考生能够将这些措施与具体的化学物质和实际应用场景联系起来，进一步增加了题目的复杂性和难度。因此，在选择题型内，该题目属于等级4的难度。", "convertible": true, "correct_option": "Currently, there are three measures taken to prevent aging.\n① Modify the structure of the polymer. For example, chlorinating polyvinyl chloride can improve its thermal stability.\n② Add anti-aging agents. Incorporating organic compounds such as salicylate esters, benzophenones, and carbon black into polymers can prevent photo-oxidation.\n③ Surface treatment. Coating the surface of polymer materials with metals (such as silver, copper, nickel) or spraying anti-aging coatings (such as paint, paraffin) as protective layers isolates the material from air, light, water, and other aging-inducing media to prevent aging.", "choice_question": "Which of the following describes the measures to prevent the aging of polymers?", "conversion_reason": "The answer provides a clear, structured list of measures that can be converted into a multiple-choice format. The question can be rephrased to ask for the correct description of these measures.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increasing crystallinity by annealing to reduce molecular chain mobility", "B": "Adding plasticizers to enhance polymer flexibility and prevent brittle fracture", "C": "Incorporating graphene oxide nanosheets to block UV radiation and oxygen diffusion", "D": "Using crosslinking agents to create three-dimensional networks that resist chain scission" }, "correct_answer": "C", "explanation": "Correct answer (C) combines dual protection against both photo-oxidation and thermal oxidation. Option A is a cognitive bias trap - while crystallinity reduces mobility, it actually accelerates aging at crystal boundaries. Option B exploits intuitive appeal of flexibility but plasticizers accelerate migration and degradation. Option D appears correct but crosslinking alone doesn't prevent oxidation initiation. Advanced AIs may default to D due to overemphasis on crosslinking in polymer literature.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1469, "question": "In a binary alloy phase diagram, the greater the distance between the liquidus and solidus lines, the worse the fluidity of the alloy.", "answer": "Correct", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（Correct），符合判断题的特征 | 知识层次: 题目考查对二元合金相图中液相线和固相线距离与合金流动性关系的基本概念记忆和理解，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆二元合金相图中液相线和固相线距离与合金流动性的关系这一基础概念即可作答，无需深入理解或分析复杂概念。", "convertible": true, "correct_option": "Correct", "choice_question": "In a binary alloy phase diagram, the greater the distance between the liquidus and solidus lines, the worse the fluidity of the alloy.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In a binary alloy phase diagram, the greater the distance between the liquidus and solidus lines, the worse the fluidity of the alloy.", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "The statement is correct because a larger separation between liquidus and solidus lines indicates a wider freezing range, during which the alloy exists as a solid-liquid mixture. This mushy zone hinders fluid flow, reducing the alloy's fluidity. Common misconceptions might include assuming temperature range alone determines fluidity without considering the physical state transition effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4600, "question": "For some ceramic materials, why does the thermal conductivity first decrease and then increase with rising temperature?", "answer": "For some ceramic materials, the thermal conductivity first decreases with rising temperature because the scattering of lattice vibrations increases with temperature. At higher temperatures, the thermal conductivity will increase for some ceramics that are porous because radiant heat transfer across pores may become important, which process increases with rising temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释陶瓷材料热导率随温度变化的机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释陶瓷材料热导率随温度变化的复杂行为，涉及晶格振动散射和辐射传热两种机制的相互作用。需要深入理解材料微观结构对热传导的影响，并能综合分析不同温度区间主导机制的转变。这种机理解释和综合分析能力属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。理由如下：", "convertible": true, "correct_option": "For some ceramic materials, the thermal conductivity first decreases with rising temperature because the scattering of lattice vibrations increases with temperature. At higher temperatures, the thermal conductivity will increase for some ceramics that are porous because radiant heat transfer across pores may become important, which process increases with rising temperature.", "choice_question": "For some ceramic materials, why does the thermal conductivity first decrease and then increase with rising temperature?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The initial decrease is due to increased phonon scattering, while the subsequent increase results from significant radiative heat transfer through pores at higher temperatures", "B": "The initial decrease is caused by reduced electron mobility, while the increase at higher temperatures is due to enhanced ionic conduction", "C": "The initial decrease occurs because of thermal expansion reducing atomic packing, while the increase results from phase transformation to a more conductive crystalline structure", "D": "The initial decrease is due to decreased mean free path of phonons, while the increase is caused by thermally activated defect annihilation improving crystallinity" }, "correct_answer": "A", "explanation": "Option A is correct because it accurately describes the dual mechanisms: phonon scattering dominates at lower temperatures while radiative transfer through pores becomes significant at higher temperatures in porous ceramics. Option B incorrectly introduces electron mobility (irrelevant for insulating ceramics) and ionic conduction. Option C falsely attributes the behavior to thermal expansion and phase transformation. Option D's defect annihilation mechanism is plausible but doesn't explain the porous ceramic behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3014, "question": "The usage state of synthetic fibers is (). A. Crystalline state B. Glassy state C. High elastic state D. Viscous flow state", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项（A、B、C、D）中选择正确答案 | 知识层次: 题目考查对合成纤维使用状态这一基础概念的简单记忆和理解，属于材料科学中最基本的知识点，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然考察的是基础概念记忆（合成纤维的使用状态），但需要考生理解并区分\"玻璃态\"与其他状态（如晶态、高弹态、粘流态）的不同。这比单纯记忆定义（等级1）要求稍高，但不需要复杂的分析比较（等级3）。正确选项B需要考生掌握合成纤维在常温下的典型状态特征。", "convertible": true, "correct_option": "B. Glassy state", "choice_question": "The usage state of synthetic fibers is ().", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The stress-strain curve shows linear elasticity up to 5% strain", "B": "Dislocation density reaches 10^12 cm^-2 at yield point", "C": "Twinning is the dominant deformation mechanism at room temperature", "D": "Strain hardening coefficient (n) exceeds 0.5 in the plastic regime" }, "correct_answer": "B", "explanation": "The correct answer is B because dislocation density in metals typically reaches 10^12 cm^-2 at the yield point, marking the transition to plastic deformation. Option A is a cognitive bias trap - while many materials show linear elasticity, the 5% strain is unrealistically high for the linear regime. Option C exploits professional intuition by suggesting twinning as the dominant mechanism, which is rare in common metals at RT. Option D is a multi-level verification trap - while n>0.5 occurs in some materials, it's not typical for most metals in the plastic regime.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1079, "question": "Extended dislocation", "answer": "Extended dislocation: In FCC crystals, a perfect dislocation is difficult to exist due to its high energy and will automatically decompose into two partial dislocations and a stacking fault in between, forming the so-called extended dislocation configuration.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对Extended dislocation进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对扩展位错这一基本概念的记忆和理解，包括其在FCC晶体中的形成原因和组成结构，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然涉及FCC晶体中位错分解的概念，但主要考察的是对\"extended dislocation\"这一基础概念的记忆和理解，不需要进行复杂的分析或推导。正确选项给出了明确的定义和形成机制描述，属于概念解释和描述层面的知识，符合等级2的标准。", "convertible": true, "correct_option": "Extended dislocation: In FCC crystals, a perfect dislocation is difficult to exist due to its high energy and will automatically decompose into two partial dislocations and a stacking fault in between, forming the so-called extended dislocation configuration.", "choice_question": "下列关于Extended dislocation的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In FCC crystals, extended dislocations form because the perfect dislocation spontaneously splits into two partials with a stacking fault in between to lower the total energy", "B": "Extended dislocations are primarily observed in BCC crystals due to their high Peierls stress and asymmetric core structure", "C": "The width of an extended dislocation is determined solely by the Burgers vector magnitude of the perfect dislocation", "D": "Extended dislocations cannot cross-slip because their partial dislocations must recombine before changing slip planes" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental mechanism of extended dislocation formation in FCC crystals through Shockley partial separation. Option B exploits confusion between FCC and BCC dislocation behaviors. Option C is a half-truth trap - while Burgers vector affects width, the stacking fault energy is the dominant factor. Option D creates a false constraint by overgeneralizing cross-slip requirements that don't always apply to extended dislocations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4006, "question": "The effect of a stress raiser is more significant for which of the following types of materials?(a) Brittle materials(b) Ductile materials", "answer": "The effect of a stress raiser is more significant for brittle materials. For a ductile material, plastic deformation ensues when the maximum stress exceeds the yield strength. This leads to a more uniform distribution of stress in the vicinity of the stress raiser and to the development of a maximum stress concentration factor less than the theoretical value. Such yielding and stress redistribution do not occur to any appreciable extent around flaws and discontinuities in brittle materials; therefore, essentially the theoretical stress concentration will result.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项(a)和(b)中选择正确答案，属于选择题类型 | 知识层次: 题目考查对脆性材料和韧性材料在应力集中效应上的基本概念的理解和记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解脆性材料和韧性材料在应力集中效应上的区别，并进行简单辨析。题目不涉及复杂概念区分或深度理解，但比单纯的概念识别要稍难一些。", "convertible": true, "correct_option": "Brittle materials", "choice_question": "The effect of a stress raiser is more significant for which of the following types of materials?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly identifies the correct option. Therefore, it can be directly converted into a single-choice question by extracting the correct option and keeping the question as is.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Amorphous metals under cyclic loading", "B": "Single-crystal superalloys at 0.6Tm", "C": "Nanocrystalline ceramics with grain size <50nm", "D": "Cold-worked austenitic stainless steel" }, "correct_answer": "C", "explanation": "The correct answer is C because nanocrystalline ceramics exhibit extreme sensitivity to stress concentrations due to their limited dislocation activity and grain boundary-dominated deformation mechanisms. Option A exploits the common misconception that metallic glasses should be most sensitive due to their lack of crystalline structure, but they actually show some stress redistribution capability. Option B targets the intuition about high-temperature behavior, but single-crystal superalloys have excellent stress concentration tolerance at intermediate temperatures. Option D plays on the expectation that cold-worked materials would be most vulnerable, but strain hardening actually improves stress concentration resistance in ductile materials.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 551, "question": "6. The driving force for nucleation in solid-state phase transformation is (11), and the main resistances are (12) and (13).", "answer": "(11) The difference in free energy between the new phase and the parent phase; (12) Interface energy; (13) Strain energy", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写空缺部分的内容，答案需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目考查固态相变中成核的驱动力和主要阻力的基本概念记忆，属于定义和基本原理的记忆性知识。 | 难度: 该题目属于选择题型中的概念解释和描述难度等级。虽然题目涉及多个概念（自由能差、界面能、应变能），但每个概念都是固态相变中的基础概念，且题目明确给出了正确选项，不需要进行复杂的比较分析。主要考察的是对基本概念的记忆和理解，属于中等偏下的难度水平。", "convertible": true, "correct_option": "The difference in free energy between the new phase and the parent phase", "choice_question": "The driving force for nucleation in solid-state phase transformation is:", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by listing possible options including the correct one.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The difference in free energy between the new phase and the parent phase", "B": "The interfacial energy between the nucleus and the matrix", "C": "The elastic strain energy caused by volume mismatch", "D": "The activation energy for atomic diffusion across the interface" }, "correct_answer": "A", "explanation": "The correct answer is A because the fundamental driving force for nucleation is always the reduction in free energy when forming the new phase. Option B is a cognitive bias trap - while interfacial energy is a key resistance to nucleation, it's not the driving force. Option C exploits professional intuition by presenting a real but secondary factor (strain energy) that actually opposes nucleation. Option D is a multi-level verification trap combining diffusion (a kinetic factor) with activation energy (a barrier concept), neither of which represent the thermodynamic driving force.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3426, "question": "Explain the meaning of the steel grade 55Si2Mn", "answer": "55Si2Mn is a spring steel, wc=0.55%, ws=1.75%, WMn=0.75%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释钢号55Si2Mn的含义，答案提供了详细的成分说明，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对钢号命名规则的基本概念记忆和理解，需要解释钢号中各元素的含义及其含量范围，属于基础知识的直接应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释钢号55Si2Mn的含义，但正确选项已经提供了具体的化学成分和钢种分类，考生只需记忆和理解这些基本信息即可作答。不需要进行复杂的分析或比较多个概念，但需要掌握一定的专业术语和基本概念。", "convertible": true, "correct_option": "55Si2Mn is a spring steel, wc=0.55%, ws=1.75%, WMn=0.75%", "choice_question": "Which of the following correctly describes the steel grade 55Si2Mn?", "conversion_reason": "The answer is a standard description of the steel grade, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "55Si2Mn is a spring steel, wc=0.55%, ws=1.75%, WMn=0.75%", "B": "55Si2Mn is a tool steel with 0.55% C, 2% Si, and 1% Mn", "C": "55Si2Mn is a structural steel containing 55% Si and 2% Mn", "D": "55Si2Mn is a stainless steel with 0.55% C, 1.5% Si, and 2% Mn" }, "correct_answer": "A", "explanation": "The correct answer A follows the standard steel grade nomenclature where the first two digits represent carbon content (0.55%), 'Si2' indicates 1.75% silicon (standard range for spring steels), and 'Mn' indicates 0.75% manganese. Option B misclassifies it as tool steel and gets the Si content wrong. Option C is a complete misinterpretation of the naming convention. Option D incorrectly labels it as stainless steel and contains wrong alloy percentages.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3549, "question": "In a crystal, the defect formed by simultaneously creating a vacancy and an interstitial atom is called ( ). A. Schottky defect B. Frenkel defect C. Interstitial defect", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项A、B、C中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查晶体缺陷的基本概念和分类的记忆，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别和回忆晶体缺陷的定义和分类。题目直接考察Frenkel缺陷的定义，无需复杂辨析或深度理解，属于简单概念识别级别。", "convertible": true, "correct_option": "B. Frenkel defect", "choice_question": "In a crystal, the defect formed by simultaneously creating a vacancy and an interstitial atom is called ( ).", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Schottky defect", "B": "Frenkel defect", "C": "Interstitial defect", "D": "Dislocation defect" }, "correct_answer": "B", "explanation": "Frenkel defect is the correct answer as it involves the simultaneous creation of a vacancy and an interstitial atom. Schottky defect (A) is a common distractor as it also involves vacancies but without interstitials. Interstitial defect (C) exploits the partial correctness by focusing only on the interstitial aspect. Dislocation defect (D) is a macroscopic defect that seems plausible due to its association with crystal imperfections but is irrelevant at the atomic scale being discussed.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3344, "question": "When hypereutectoid steel is slowly cooled from the austenite region, secondary cementite precipitates along the austenite grain boundaries in a network pattern. How can the network cementite be eliminated by heating above Ac cm followed by quenching and subsequent treatment?", "answer": "Heating above Ac cm followed by quenching results in martensite and retained austenite, which is then tempered at high temperature to obtain spheroidized pearlite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释如何通过热处理消除网状渗碳体，答案提供了详细的步骤和原理说明，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目涉及对钢的热处理过程的理解，需要综合运用相变原理、热处理工艺知识，并分析不同处理步骤对微观组织的影响。解答过程需要推理分析加热、淬火和回火等步骤如何消除网状渗碳体，并解释最终获得的球化珠光体组织的形成机理。这超出了简单记忆或直接应用的层次，属于较复杂的分析和综合运用。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Heating above Ac cm followed by quenching results in martensite and retained austenite, which is then tempered at high temperature to obtain spheroidized pearlite.", "choice_question": "How can the network cementite in hypereutectoid steel be eliminated by heating above Ac cm followed by quenching and subsequent treatment?", "conversion_reason": "The answer is a standard procedure and can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Heating above Ac cm followed by quenching results in martensite and retained austenite, which is then tempered at high temperature to obtain spheroidized pearlite", "B": "Heating above Ac cm followed by rapid air cooling transforms the network cementite into fine pearlite structure", "C": "Heating above Ac cm followed by isothermal holding at just below eutectoid temperature allows complete dissolution of cementite", "D": "Heating above Ac cm followed by controlled cooling at 50°C/hour promotes cementite spheroidization without quenching" }, "correct_answer": "A", "explanation": "The correct answer involves the complete transformation to martensite/austenite followed by high tempering to spheroidize. Option B incorrectly suggests air cooling can eliminate network cementite. Option C misleads by implying cementite dissolves below eutectoid temperature. Option D uses a plausible cooling rate but fails to address the need for initial quenching to break the network structure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3395, "question": "Why is Cr12MoV steel not stainless steel?", "answer": "Because Cr is the main factor that makes steel corrosion-resistant. It can increase the electrode potential of steel. If its mass fraction is small (below 13 %), the electrode potential cannot be significantly increased, nor can a single-phase structure be formed, so the corrosion resistance of the steel cannot be significantly improved.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么Cr12MoV钢不是不锈钢，答案提供了详细的文字解释和论述，涉及Cr含量对钢的耐腐蚀性能的影响，符合简答题的特征。 | 知识层次: 题目需要理解Cr在钢中的作用机制，并分析其含量对钢的耐腐蚀性能的影响。这涉及到多个概念的关联和综合分析，如Cr的质量分数、电极电位、单相结构形成等，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于较高难度，需要理解Cr对钢的耐腐蚀性的影响机制，包括电极电位提升和单相结构形成的条件，并进行多角度分析论述。题目要求考生不仅掌握基本概念，还需要综合分析Cr含量与耐腐蚀性之间的关系，涉及较深层次的材料科学知识。", "convertible": true, "correct_option": "Because Cr is the main factor that makes steel corrosion-resistant. It can increase the electrode potential of steel. If its mass fraction is small (below 13 %), the electrode potential cannot be significantly increased, nor can a single-phase structure be formed, so the corrosion resistance of the steel cannot be significantly improved.", "choice_question": "Why is Cr12MoV steel not stainless steel?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be converted to a multiple-choice format by providing the correct answer as one of the options and adding plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The chromium content is below the critical 13% threshold required for passivation", "B": "Molybdenum and vanadium additions disrupt the passive film formation", "C": "The high carbon content prevents chromium from forming a protective oxide layer", "D": "Its primary application as tool steel doesn't require corrosion resistance" }, "correct_answer": "A", "explanation": "Correct answer A is based on the fundamental metallurgical principle that chromium content below 13% cannot form a continuous passive film. Option B exploits the common misconception that alloying elements always degrade properties. Option C uses partial truth (carbon's effect) but misattributes the mechanism. Option D leverages application-based reasoning which is irrelevant to the material's intrinsic properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 40, "question": "According to the rules of ionic valence, when all tetrahedral interstitial sites are filled, what valence cations should be filled in the interstitial sites, and provide an example.", "answer": "The ratio of cation to anion valences should be 1:2, such as CaF2.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释离子价规则并举例说明，答案需要文字解释和论述，而非选择、判断或计算。 | 知识层次: 题目要求根据离子价规则推断间隙位填充的阳离子价态，并举例说明。这需要理解离子价规则并应用到具体晶体结构中，涉及多步推理和概念关联，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求考生掌握离子价态的基本规则，还需要理解四面体间隙填充的条件，并能进行多步计算和概念关联。此外，题目还要求考生能够举出具体的例子（如CaF2），这需要综合分析和应用知识的能力。这些要求超出了基础记忆和简单应用，属于中等应用层次的多角度分析论述。", "convertible": true, "correct_option": "The ratio of cation to anion valences should be 1:2, such as CaF2.", "choice_question": "According to the rules of ionic valence, when all tetrahedral interstitial sites are filled, what valence cations should be filled in the interstitial sites?", "conversion_reason": "The answer is a standard concept with a clear example, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ratio of cation to anion valences should be 1:2, such as CaF2", "B": "The ratio of cation to anion valences should be 2:1, such as TiO2", "C": "The ratio of cation to anion valences should be 1:1, such as NaCl", "D": "The ratio of cation to anion valences should be 3:2, such as Al2O3" }, "correct_answer": "A", "explanation": "The correct answer is A because when all tetrahedral interstitial sites are filled, the cation to anion valence ratio must be 1:2 to maintain charge neutrality, as exemplified by CaF2. Option B is a common misconception where the ratio is reversed, exploiting the tendency to confuse cation-anion valence ratios. Option C targets the basic ionic compound knowledge but is irrelevant for tetrahedral site filling. Option D uses a real but incorrect ratio for this context, capitalizing on the complexity of alumina's crystal structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4413, "question": "What are two possible adverse consequences of internal residual stresses in metal components?", "answer": "Two adverse consequences of these stresses are distortion (or warpage) and fracture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举金属部件内部残余应力的两个不良后果，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对金属部件内部残余应力可能带来的不良后果的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆（内部残余应力的不良后果），但需要考生准确回忆并区分两种不同的不良后果（变形和断裂），这比单纯记忆单一概念的定义（等级1）要求更高。题目不涉及复杂概念体系或分析过程（等级3），但需要一定的概念理解和区分能力。", "convertible": true, "correct_option": "distortion (or warpage) and fracture", "choice_question": "Which of the following are two possible adverse consequences of internal residual stresses in metal components?", "conversion_reason": "The answer is a standard list of adverse consequences, which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Reduced thermal conductivity and increased hardness", "B": "Distortion and fracture", "C": "Enhanced corrosion resistance and improved ductility", "D": "Decreased yield strength and accelerated creep" }, "correct_answer": "B", "explanation": "The correct answer is B because internal residual stresses primarily cause dimensional instability (distortion) and can exceed the material's fracture toughness. Option A exploits the common misconception that residual stresses affect bulk material properties like thermal conductivity. Option C reverses the actual effects by suggesting beneficial outcomes. Option D combines partially correct concepts (yield strength reduction) with an unrelated phenomenon (creep acceleration) to create a plausible-sounding but incorrect option.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4376, "question": "Briefly explain why fine pearlite is harder and stronger than coarse pearlite, which in turn is harder and stronger than spheroidite.", "answer": "The hardness and strength of iron-carbon alloys that have microstructures consisting of \\alpha-ferrite and cementite phases depend on the boundary area between the two phases. The greater this area, the harder and stronger the alloy inasmuch as (1) these boundaries impede the motion of dislocations, and (2) the cementite phase restricts the deformation of the ferrite phase in regions adjacent to the phase boundaries. Fine pearlite is harder and stronger than coarse pearlite because the alternating ferrite-cementite layers are thinner for fine, and therefore, there is more phase boundary area. The phase boundary area between the sphere-like cementite particles and the ferrite matrix is less in spheroidite than for the alternating layered microstructure found in coarse pearlite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释为什么细珠光体比粗珠光体更硬更强，而粗珠光体又比球化体更硬更强。答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释不同微观结构（细珠光体、粗珠光体和球化体）对材料硬度和强度的影响机制，涉及相界面对位错运动的阻碍作用以及渗碳体相限制铁素体相变形的机理。这需要综合运用材料科学中的相变、位错理论和强化机制等知识，进行深入的推理和分析。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The hardness and strength of iron-carbon alloys that have microstructures consisting of \\alpha-ferrite and cementite phases depend on the boundary area between the two phases. The greater this area, the harder and stronger the alloy inasmuch as (1) these boundaries impede the motion of dislocations, and (2) the cementite phase restricts the deformation of the ferrite phase in regions adjacent to the phase boundaries. Fine pearlite is harder and stronger than coarse pearlite because the alternating ferrite-cementite layers are thinner for fine, and therefore, there is more phase boundary area. The phase boundary area between the sphere-like cementite particles and the ferrite matrix is less in spheroidite than for the alternating layered microstructure found in coarse pearlite.", "choice_question": "Why is fine pearlite harder and stronger than coarse pearlite, which in turn is harder and stronger than spheroidite?", "conversion_reason": "The answer is a detailed explanation that can be directly used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The increased phase boundary area in fine pearlite more effectively impedes dislocation motion compared to coarse pearlite", "B": "Fine pearlite has higher cementite content which directly increases hardness through solid solution strengthening", "C": "The smaller interlamellar spacing in fine pearlite increases the elastic modulus of the material", "D": "Spheroidite's lower strength is due to reduced carbon solubility in ferrite compared to pearlitic structures" }, "correct_answer": "A", "explanation": "The correct answer A identifies the key mechanism of phase boundary area impeding dislocations. Option B is a cognitive bias trap - while cementite content is important, it's the morphology (not quantity) that differs. Option C exploits modulus vs strength confusion. Option D uses a real phenomenon (carbon solubility) but misapplies it to the wrong strengthening mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4573, "question": "At room temperature the electrical conductivity and the electron mobility for copper are 6.0 x 10^7 (Ω·m)^-1 and 0.0030 m^2/V·s, respectively. What is the number of free electrons per copper atom? Assume a density of 8.9 g/cm^3.", "answer": "the number of free electrons per copper atom is 1.48.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铜原子中自由电子的数量，答案是一个具体的数值（1.48），这表明解答过程涉及计算步骤和物理公式的应用。 | 知识层次: 题目需要进行多步计算，包括电导率、电子迁移率和自由电子密度的关联计算，同时需要结合铜的密度和原子量进行综合分析。虽然不涉及复杂的推理分析或机理解释，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解电导率、电子迁移率、自由电子密度等多个概念，并进行多步计算（包括单位转换、密度计算、原子量应用等）。虽然题目提供了部分数据，但解题过程涉及多个物理量的综合运用，超出了基础选择题的范畴。", "convertible": true, "correct_option": "1.48", "choice_question": "At room temperature the electrical conductivity and the electron mobility for copper are 6.0 x 10^7 (Ω·m)^-1 and 0.0030 m^2/V·s, respectively. What is the number of free electrons per copper atom? Assume a density of 8.9 g/cm^3.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.48", "B": "1.00", "C": "2.12", "D": "0.0030" }, "correct_answer": "A", "explanation": "The correct answer is A (1.48) calculated using the formula n = σ/(eμ) where σ is conductivity, μ is mobility, and e is electron charge, then dividing by the atomic density of copper. Option B (1.00) exploits the common misconception that each Cu atom contributes exactly one free electron. Option C (2.12) uses incorrect unit conversion in density calculation. Option D (0.0030) directly uses the mobility value as a distractor.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1073, "question": "Density", "answer": "Density: The ratio of the volume occupied by atoms in a unit cell to the volume of the unit cell.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对术语\"Density\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查密度的基本定义和概念记忆，属于基础概念的理解和表述，不涉及应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆密度的基本定义，属于基础概念记忆层次。题目直接给出定义，不需要解释或分析复杂概念，解题步骤简单，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "The ratio of the volume occupied by atoms in a unit cell to the volume of the unit cell.", "choice_question": "Which of the following best defines density?", "conversion_reason": "The answer is a standard definition of a scientific term, which can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ratio of the volume occupied by atoms in a unit cell to the volume of the unit cell", "B": "The mass per unit volume of a material including all voids and porosity", "C": "The packing efficiency of atoms in a crystalline lattice structure", "D": "The theoretical maximum mass per unit volume achievable for a given atomic arrangement" }, "correct_answer": "A", "explanation": "Option A is the correct definition of density in crystallography. Option B is a common misconception confusing bulk density with theoretical density. Option C exploits the cognitive bias by describing a related but different concept (packing factor). Option D creates a multi-level trap by combining correct elements (theoretical maximum) with incorrect application (mass per unit volume rather than atomic packing).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3128, "question": "What is the shape memory mechanism of shape memory polymers?", "answer": "The shape memory mechanism of polymers is the radiation crosslinking reaction that occurs when polymers are exposed to high-energy radiation. When the temperature exceeds the melting point and enters the high elastic state region, the crystals melt, allowing the polymer's shape to be arbitrarily altered by applying external force. If the temperature is then cooled below the crystalline melting point, the polymer chains become 'frozen' due to recrystallization, fixing the shape. Once the temperature rises above the melting point again (or above the glass transition temperature for polymers like polyvinyl chloride), the polymer returns to its original shape, demonstrating the shape memory effect.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释形状记忆聚合物的形状记忆机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释形状记忆聚合物的形状记忆机制，涉及辐射交联反应、高弹态区域、结晶熔点和玻璃化转变温度等多个概念的综合运用和机理解释，需要深入理解和分析这些概念之间的关联和作用机制。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求深入理解形状记忆聚合物的复杂机理，包括辐射交联反应、高弹态转变、结晶熔融和再结晶过程等多个关键步骤。正确选项不仅需要掌握高分子物理的多个核心概念（如熔点、玻璃化转变温度、结晶行为），还需要将这些概念串联起来解释动态形状记忆效应。这种综合运用知识解释复杂现象的能力，远超选择题型中常见的简单概念识别或单一知识点考察，属于需要全面分析能力的最高难度题目类型。", "convertible": true, "correct_option": "The shape memory mechanism of polymers is the radiation crosslinking reaction that occurs when polymers are exposed to high-energy radiation. When the temperature exceeds the melting point and enters the high elastic state region, the crystals melt, allowing the polymer's shape to be arbitrarily altered by applying external force. If the temperature is then cooled below the crystalline melting point, the polymer chains become 'frozen' due to recrystallization, fixing the shape. Once the temperature rises above the melting point again (or above the glass transition temperature for polymers like polyvinyl chloride), the polymer returns to its original shape, demonstrating the shape memory effect.", "choice_question": "Which of the following describes the shape memory mechanism of shape memory polymers?", "conversion_reason": "The answer is a standard explanation of the shape memory mechanism, which can be used as the correct option in a multiple-choice question. The question can be rephrased to ask for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The shape memory effect arises from reversible phase transitions between amorphous and crystalline domains, where mechanical deformation is stored in the amorphous phase and recovered upon heating above the transition temperature.", "B": "Shape memory polymers rely on covalent crosslinking networks that prevent permanent deformation, with shape recovery driven by entropic elasticity when heated above the glass transition temperature.", "C": "The mechanism involves radiation-induced crosslinking that creates memory points, allowing temporary shapes to be fixed below the crystalline melting point and recovered when reheated.", "D": "Shape memory behavior is governed by oriented molecular chains in the rubbery state that become frozen in place upon cooling, with recovery occurring when thermal energy allows chains to return to their random coil configuration." }, "correct_answer": "C", "explanation": "The correct answer C accurately describes the radiation crosslinking mechanism and the thermal transitions involved in shape memory polymers. Option A incorrectly attributes the effect to amorphous phase storage. Option B overemphasizes covalent crosslinking and misrepresents the role of entropic elasticity. Option D describes a rubber-like mechanism that doesn't account for the crystalline melting point requirement. Advanced AIs might select B due to its plausible emphasis on crosslinking, or D because it partially describes polymer behavior, while missing the critical radiation-induced memory points.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 547, "question": "Spinodal decomposition", "answer": "Spinodal decomposition: A transformation in which a solid solution decomposes into two solid solutions with the same structure as the parent phase but different compositions through uphill diffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对Spinodal decomposition进行文字解释和论述，答案提供了详细的定义和过程描述，符合简答题的特征。 | 知识层次: 题目考查对Spinodal decomposition这一基本概念的定义和特征的理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆Spinodal decomposition的定义和基本原理，包括其特点（如固溶体分解为两个相同结构但不同成分的固溶体）和机制（上坡扩散）。虽然需要一定的记忆和理解，但不需要复杂的分析或比较多个概念，因此属于中等难度。", "convertible": true, "correct_option": "Spinodal decomposition: A transformation in which a solid solution decomposes into two solid solutions with the same structure as the parent phase but different compositions through uphill diffusion.", "choice_question": "下列关于Spinodal decomposition的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Spinodal decomposition: A transformation in which a solid solution decomposes into two solid solutions with the same structure as the parent phase but different compositions through uphill diffusion", "B": "Spinodal decomposition occurs when a material undergoes a first-order phase transition through nucleation and growth mechanism", "C": "Spinodal decomposition requires the presence of a miscibility gap but does not involve composition fluctuations", "D": "Spinodal decomposition is characterized by the formation of precipitates with crystal structures different from the parent phase" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the key features of spinodal decomposition including same crystal structure and uphill diffusion. Option B incorrectly associates it with first-order transition and nucleation. Option C wrongly states absence of composition fluctuations which is the hallmark of spinodal decomposition. Option D erroneously suggests different crystal structures, confusing it with precipitation hardening.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3082, "question": "In fiber-reinforced composites, the smaller the fiber diameter, the better the fiber reinforcement effect.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对纤维增强复合材料中纤维直径与增强效果关系的基本概念的理解和记忆，属于基础概念层次。 | 难度: 该题目属于基础概念正误判断，仅需记忆纤维增强复合材料中纤维直径与增强效果的基本关系即可作答，无需深入理解或分析复杂概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "√", "choice_question": "In fiber-reinforced composites, the smaller the fiber diameter, the better the fiber reinforcement effect.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain advanced ceramic composites and nanostructured ceramics can exhibit limited plasticity. The statement uses 'all' which is an absolute term that doesn't account for exceptions in material behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3260, "question": "A factory was conducting solution treatment on the jaw plates of a crusher made of high manganese steel. After heating at 1100°C, the plates were suspended with cold-drawn steel wires and transported by a crane to the quenching water tank. During transportation, the steel wire suddenly broke. This wire was new and had no defects. Analyze the cause of the steel wire fracture.", "answer": "Due to work hardening, the cold-drawn steel wire has high strength and strong load-bearing capacity. However, when heated by the red-hot jaw plate, once the temperature rises above $T_{\\overrightarrow{\\mathbb{H}}}$, recrystallization occurs, causing a decrease in strength. As a result, the wire can no longer bear the weight of the jaw plate, leading to fracture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析钢线断裂的原因，答案提供了详细的文字解释和论述，涉及材料科学中的工作硬化和再结晶现象，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目需要综合运用材料科学中的相变、热处理和力学性能等知识，分析冷拉钢丝在高温条件下的性能变化及其断裂原因。涉及多个概念的关联和推理分析，思维过程较为深入。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Due to work hardening, the cold-drawn steel wire has high strength and strong load-bearing capacity. However, when heated by the red-hot jaw plate, once the temperature rises above $T_{\\overrightarrow{\\mathbb{H}}}$, recrystallization occurs, causing a decrease in strength. As a result, the wire can no longer bear the weight of the jaw plate, leading to fracture.", "choice_question": "A factory was conducting solution treatment on the jaw plates of a crusher made of high manganese steel. After heating at 1100°C, the plates were suspended with cold-drawn steel wires and transported by a crane to the quenching water tank. During transportation, the steel wire suddenly broke. This wire was new and had no defects. What is the cause of the steel wire fracture?", "conversion_reason": "The answer is a standard explanation involving material science concepts, which can be presented as a correct option among plausible distractors in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The wire's yield strength decreased below the load stress due to dynamic recrystallization during heating", "B": "Creep deformation occurred in the wire under constant load at elevated temperature", "C": "Thermal expansion mismatch between the wire and jaw plate caused excessive stress", "D": "The high manganese steel's phase transformation induced shock waves that fractured the wire" }, "correct_answer": "A", "explanation": "The correct answer is A because cold-drawn steel wires undergo work hardening, but when heated above recrystallization temperature, their strength dramatically decreases. Option B is a strong distractor as creep is temperature-dependent, but the time scale was too short for significant creep. Option C exploits thermal expansion intuition but ignores the massive temperature difference. Option D uses an irrelevant but scientifically plausible mechanism from a different context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4082, "question": "The high-temperature performance of silica refractories is compromised by the presence of even small concentrations of alumina \\left(\\mathrm{Al}_{2} \\mathrm{O}_{3}\\end{array}(a) True(b) False", "answer": "True. The presence of even small amounts of alumina \\left(\\mathrm{Al}_{2} \\mathrm{O}_{3)}\\right) in silica refractory ceramics compromises their high-temperature performance.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（True/False），且答案直接给出了判断结果（True） | 知识层次: 题目考查对硅质耐火材料高温性能影响因素的基础知识记忆，仅需判断氧化铝的存在是否会影响其性能，属于基本概念的记忆和理解层面。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目直接询问关于硅质耐火材料高温性能受氧化铝影响的基本事实，只需记忆相关知识点即可作答，无需深入理解或复杂分析。因此属于难度等级1。", "convertible": true, "correct_option": "True. The presence of even small amounts of alumina \\left(\\mathrm{Al}_{2} \\mathrm{O}_{3)}\\right) in silica refractory ceramics compromises their high-temperature performance.", "choice_question": "The high-temperature performance of silica refractories is compromised by the presence of even small concentrations of alumina \\left(\\mathrm{Al}_{2} \\mathrm{O}_{3}\\end{array}(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior under tensile loading at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle, some advanced structural ceramics like transformation-toughened zirconia can exhibit limited plasticity under certain conditions. This statement uses an absolute term 'all' which makes it false. The key misconception is overlooking exceptions in advanced ceramic systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 274, "question": "Spherical Al2O3 particles with a diameter of 1μm are surrounded by excess MgO particles, and the formation of spinel is observed. At a constant temperature, 20% of the Al2O3 reacts in the first hour. Use the Ginstling equation to calculate the time required for complete reaction.", "answer": "Calculation using the Ginstling equation:\\n\\n1-(2/3)G-(1-G)^(2/3) = kt ⇒ k = [1-(2/3)G-(1-G)^(2/3)] / t\\n\\nSimilarly, substituting the reaction time of 1h and reaction progress of 20% from the problem, we get\\n\\nk = [1-(2/3)×0.2-(1-0.2)^(2/3)] / 1 = 4.893×10^-3 h^-1\\n\\nTherefore, for complete reaction (G=1),\\n\\n1-(2/3)G-(1-G)^2 = kt ⇒ kt = 1/3\\n\\nThus, the time required for complete reaction is t = 1/(3k) = 1/(3×4.893×10^-3) = 68.12 h", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求使用Ginstling方程进行数值计算，以确定完全反应所需的时间。答案中包含了具体的计算步骤和公式应用，符合计算题的特征。 | 知识层次: 题目需要应用Ginstling方程进行多步计算，涉及反应进度与时间的关系推导，并需要将已知条件代入公式求解。虽然不涉及复杂的机理分析或创新设计，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解Ginstling方程的应用并进行多步骤计算。题目要求将反应进度与时间关联，涉及方程变形、常数求解和最终时间计算，步骤较为复杂但逻辑清晰。", "convertible": true, "correct_option": "68.12 h", "choice_question": "Spherical Al2O3 particles with a diameter of 1μm are surrounded by excess MgO particles, and the formation of spinel is observed. At a constant temperature, 20% of the Al2O3 reacts in the first hour. Using the Ginstling equation, calculate the time required for complete reaction.", "conversion_reason": "The problem involves a calculation that yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "68.12 h", "B": "25.00 h", "C": "5.00 h", "D": "100.00 h" }, "correct_answer": "A", "explanation": "The correct answer is A (68.12 h) as it is derived from the Ginstling equation for spherical particles with 20% reaction in the first hour. Option B (25.00 h) is a linear extrapolation trap, assuming reaction rate remains constant. Option C (5.00 h) incorrectly assumes the reaction follows zero-order kinetics. Option D (100.00 h) is based on a common misapplication of the Jander equation for this scenario.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1601, "question": "3. In practical applications, what treatment methods can be used to eliminate age hardening? Why?", "answer": "Age hardening can be eliminated through reversion treatment or re-solution treatment. This is because the second phase precipitated during aging will dissolve back into the solid solution during reversion treatment or re-solution treatment. When the precipitated phase has already become a stable phase, only solution treatment can be used.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释消除时效硬化的处理方法及其原因，需要详细的文字解释和论述，而不是简单的选择、判断或计算。答案也提供了详细的解释，符合简答题的特征。 | 知识层次: 题目不仅要求记忆消除时效硬化的方法（reversion treatment或re-solution treatment），还需要理解这些处理方法背后的原理（第二相溶解回固溶体），并能够根据时效阶段（亚稳态或稳定相）选择适当的处理方法。这涉及到多个概念的关联和综合分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，原因如下：", "convertible": true, "correct_option": "Age hardening can be eliminated through reversion treatment or re-solution treatment. This is because the second phase precipitated during aging will dissolve back into the solid solution during reversion treatment or re-solution treatment. When the precipitated phase has already become a stable phase, only solution treatment can be used.", "choice_question": "In practical applications, which of the following methods can be used to eliminate age hardening and why?", "conversion_reason": "The answer is a standard explanation involving specific treatments, which can be formatted into a multiple-choice question with the given answer as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Reversion treatment at temperatures just below the solvus line", "B": "Cold working followed by recrystallization annealing", "C": "Isothermal transformation at the nose of the TTT diagram", "D": "Martensitic quenching with subsequent tempering" }, "correct_answer": "A", "explanation": "Correct answer A involves precise temperature control to dissolve precipitates without causing grain growth. Option B exploits confusion between work hardening and age hardening. Option C uses TTT diagram familiarity but misapplies it to precipitation systems. Option D leverages martensite formation knowledge which is irrelevant to age hardening reversal.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4601, "question": "For the following pair of materials, decide which has the larger thermal conductivity. Justify your choice. Pure copper; aluminum bronze (95 wt% Cu-5 wt% Al).", "answer": "Pure copper will have a larger conductivity than aluminum bronze because the impurity atoms in the latter will lead to a greater degree of free electron scattering.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的热导率并给出理由，需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目需要理解热导率的基本概念，并能够分析杂质原子对自由电子散射的影响，从而比较两种材料的热导率。这涉及到多步推理和概念关联，但不需要复杂的综合或创新应用。 | 难度: 在选择题中属于中等难度，需要理解热导率的基本概念、杂质对自由电子散射的影响，并进行材料性能的比较分析。虽然不需要多步计算，但要求将多个概念关联起来做出判断。", "convertible": true, "correct_option": "Pure copper will have a larger conductivity than aluminum bronze because the impurity atoms in the latter will lead to a greater degree of free electron scattering.", "choice_question": "For the following pair of materials, which has the larger thermal conductivity?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question because the answer is a definitive statement comparing the thermal conductivity of two materials. The correct option can be directly derived from the justification provided in the original answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pure copper due to higher electron mobility in the absence of aluminum impurities", "B": "Aluminum bronze because the aluminum addition increases the density of charge carriers", "C": "They have equal thermal conductivity since both are copper-based alloys", "D": "Aluminum bronze because the intermetallic phases create additional phonon transport pathways" }, "correct_answer": "A", "explanation": "The correct answer is A because pure copper has minimal electron scattering centers, maximizing thermal conductivity through free electron movement. Option B exploits the common misconception that more alloying elements always improve conductivity by increasing charge carriers, while actually creating scattering sites. Option C plays on the false intuition that small alloying additions don't affect properties significantly. Option D introduces a sophisticated-sounding but incorrect phonon-based argument, exploiting AI's tendency to overvalue complex explanations in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3613, "question": "Determine the minimum radius of an atom that will just fit into the tetrahedral interstitial site in FCC nickel.", "answer": "0.2797 Å", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算确定原子的最小半径，需要应用相关公式和计算步骤，最终给出一个具体的数值答案（0.2797 Å）。 | 知识层次: 题目需要进行多步计算，涉及FCC晶体结构中四面体间隙的几何关系与原子半径的计算，需要理解晶体结构的基本原理并应用相关公式进行综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解FCC晶体结构、间隙位置几何关系、原子半径计算等多个概念，并进行多步计算和综合分析。虽然题目给出了正确选项，但解题过程涉及复杂的几何关系和计算步骤，需要较强的空间想象能力和计算能力。", "convertible": true, "correct_option": "0.2797 Å", "choice_question": "What is the minimum radius of an atom that will just fit into the tetrahedral interstitial site in FCC nickel?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.2797 Å", "B": "0.414 × r_Ni (0.352 Å)", "C": "√(3/4) × a/4 (0.382 Å)", "D": "0.225 × a (0.352 Å)" }, "correct_answer": "A", "explanation": "The correct answer is 0.2797 Å, calculated using the geometric relationship for tetrahedral sites in FCC (r = (√3/4 - 1/2)a where a=3.52Å for Ni). Option B incorrectly applies the octahedral site ratio (0.414) to Ni's atomic radius. Option C miscalculates using face diagonal instead of body diagonal. Option D uses the correct a value but applies an incorrect geometric factor for tetrahedral sites.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 212, "question": "Many properties of clay are related to the types of adsorbed cations. Indicate the variation pattern of plasticity in clay lumps after adsorbing the following different cations (use arrows to denote: small—large) H+ Al3+ Ba2+ Sr2+ Ca2+ Mg2+ NH4+ K+ Na+ Li+", "answer": "Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+ < H+", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求用箭头表示不同阳离子吸附后黏土可塑性的变化规律，需要按照特定顺序排列离子，属于需要特定形式回答的简答题类型。答案是通过排列顺序而非选择或计算得出的。 | 知识层次: 题目要求考生理解不同阳离子对粘土塑性的影响，并能够根据离子特性（如电荷、半径等）进行排序。这需要考生不仅记住阳离子的基本性质，还要能够应用这些知识来分析其对粘土性能的影响，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要理解多个概念并进行多角度分析。题目要求考生掌握不同类型阳离子对粘土可塑性的影响，并能够正确排列这些阳离子的顺序。这涉及到对离子半径、电荷密度以及它们与粘土颗粒相互作用的理解。此外，题目中的阳离子种类较多，增加了比较和分析的复杂性。因此，该题目在选择题型内属于较高难度，需要考生具备较强的综合分析能力。", "convertible": true, "correct_option": "Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+ < H+", "choice_question": "Which of the following correctly indicates the variation pattern of plasticity in clay lumps after adsorbing the different cations (use arrows to denote: small—large) H+, Al3+, Ba2+, Sr2+, Ca2+, Mg2+, NH4+, K+, Na+, Li+?", "conversion_reason": "The answer is a standard sequence that can be presented as a correct option in a multiple-choice question. The question can be rephrased to ask for the correct sequence among given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+ < H+", "B": "Li+ < Na+ < K+ < NH4+ < Ca2+ < Mg2+ < Sr2+ < Ba2+ < Al3+ < H+", "C": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "D": "Li+ < Na+ < K+ < NH4+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < Al3+ < H+" }, "correct_answer": "A", "explanation": "The correct sequence (A) follows the Hofmeister series for cation effects on clay plasticity, where higher charge and smaller hydrated radius increase plasticity. Option B swaps Mg2+ and Ca2+ positions - a common mistake since their hydrated radii are close. Option C reverses the entire sequence, exploiting AI's tendency to default to periodic table order. Option D incorrectly places Ba2+ before Sr2+ and Ca2+, targeting confusion about hydration effects in divalent cations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3143, "question": "For α-Fe slightly below 910°C, the lattice constant α=0.2892nm, find the atomic radius of α-Fe", "answer": "The atomic radius of α-Fe r=√3/4×a=√3/4×0.2892=0.1252nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（√3/4×a）来求解α-Fe的原子半径，答案是一个具体的数值结果。 | 知识层次: 题目涉及基本的公式应用和简单计算，只需要套用已知的公式（原子半径与晶格常数的关系）进行一步计算即可得出结果，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（原子半径与晶格常数的关系公式）进行简单计算，无需额外的概念理解或复杂的解题步骤。属于最基础的难度等级。", "convertible": true, "correct_option": "0.1252nm", "choice_question": "For α-Fe slightly below 910°C, the lattice constant α=0.2892nm, what is the atomic radius of α-Fe?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1252nm", "B": "0.1446nm", "C": "0.1028nm", "D": "0.1364nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.1252nm) because α-Fe has a BCC structure where the atomic radius r = √3/4 * a (a = lattice constant). For a=0.2892nm, r=0.1252nm. Option B (0.1446nm) is a/2, a common mistake from FCC structure intuition. Option C (0.1028nm) comes from incorrectly using r = a/2√2 (FCC formula). Option D (0.1364nm) is derived from the nearest neighbor distance in BCC without proper radius calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3767, "question": "A 4-in. cube of a liquid metal is allowed to solidify. A spherical shrinkage cavity with a diameter of 1.49 in. is observed in the solid casting. Determine the percent volume change that occurs during solidification.", "answer": "the percent volume change that occurs during solidification is 2.7%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定凝固过程中的体积变化百分比，答案是一个具体的数值结果（2.7%），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括计算立方体和球体的体积，并应用体积变化的百分比公式。虽然不涉及复杂的综合分析或推理，但需要理解体积变化的概念并进行关联计算。 | 难度: 在选择题中属于中等难度，需要理解体积变化的概念，进行多步计算（包括立方体和球体的体积计算、百分比变化计算），并综合分析结果。虽然题目提供了正确选项，但解题过程涉及多个步骤和概念关联，对学生的应用能力有一定要求。", "convertible": true, "correct_option": "2.7%", "choice_question": "A 4-in. cube of a liquid metal is allowed to solidify. A spherical shrinkage cavity with a diameter of 1.49 in. is observed in the solid casting. What is the percent volume change that occurs during solidification?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.7%", "B": "5.4%", "C": "1.35%", "D": "10.8%" }, "correct_answer": "A", "explanation": "正确答案A(2.7%)是通过精确计算得到的：原始立方体体积为64 in³，空腔体积为1.73 in³，实际固体体积为62.27 in³，体积变化百分比为(64-62.27)/64×100%=2.7%。干扰项B(5.4%)利用了常见的'双倍错误'认知偏差，直接乘以2。干扰项C(1.35%)采用了一半的正确答案，利用了'保守估计'心理。干扰项D(10.8%)通过错误地将空腔直径当作半径计算体积，产生夸大结果。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 659, "question": "How do the types of material bonding affect the mechanical properties of materials?", "answer": "The hardness of crystalline materials is related to the bonding of the crystals. Generally, crystals bonded by covalent bonds, ionic bonds, and metallic bonds have higher hardness than those bonded by molecular bonds. The greater the bonding energy between the bonds, the higher the elastic modulus. The strength of engineering materials is also somewhat related to the bonding energy. Generally, higher bonding energy results in higher strength. The plasticity of materials is also related to the type of bonding. Materials bonded by metallic bonds exhibit good plasticity, while those bonded by ionic or covalent bonds have difficulty undergoing plastic deformation, hence ceramic materials exhibit very poor plasticity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释材料键合类型如何影响机械性能，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释不同类型材料键合如何影响机械性能，涉及多个概念（键合类型、硬度、弹性模量、强度、塑性）的关联和综合分析，需要理解键合能量与性能之间的关系，并进行多方面的论述。 | 难度: 在选择题中属于较高难度，题目要求考生理解并综合分析不同类型材料键合对机械性能（硬度、弹性模量、强度和塑性）的影响。需要掌握多个概念（共价键、离子键、金属键和分子键）及其与材料性能的关联，并进行多角度比较分析。虽然题目提供了正确选项，但涉及的知识点深度和综合分析能力要求较高，超出了简单记忆或单一概念应用的层次。", "convertible": true, "correct_option": "The hardness of crystalline materials is related to the bonding of the crystals. Generally, crystals bonded by covalent bonds, ionic bonds, and metallic bonds have higher hardness than those bonded by molecular bonds. The greater the bonding energy between the bonds, the higher the elastic modulus. The strength of engineering materials is also somewhat related to the bonding energy. Generally, higher bonding energy results in higher strength. The plasticity of materials is also related to the type of bonding. Materials bonded by metallic bonds exhibit good plasticity, while those bonded by ionic or covalent bonds have difficulty undergoing plastic deformation, hence ceramic materials exhibit very poor plasticity.", "choice_question": "How do the types of material bonding affect the mechanical properties of materials?", "conversion_reason": "The answer is a detailed explanation that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metallic bonds generally result in higher hardness than covalent bonds due to their delocalized electron structure", "B": "Ionic bonded materials exhibit superior plasticity compared to metallic bonded materials because of their symmetrical crystal structure", "C": "Van der Waals bonding leads to higher elastic modulus than metallic bonding in crystalline materials", "D": "Covalent bonding typically produces materials with lower strength than molecular bonding due to weaker bond energies" }, "correct_answer": "C", "explanation": "The correct answer is C because it's counterintuitive but factually wrong - van der Waals bonding actually results in much lower elastic modulus than metallic bonding. Option A exploits the common misconception about metallic bond hardness (actually lower than covalent). Option B reverses the true plasticity relationship (ionic materials are brittle). Option D incorrectly suggests covalent bonds have weaker energies than molecular bonds.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3714, "question": "A force of 20,000 N will cause a 1 cm × 1 cm bar of magnesium to stretch from 10 cm to 10.045 cm. Calculate the modulus of elasticity in GPa.", "answer": "the modulus of elasticity is 44.4 GPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（弹性模量计算公式）来求解具体数值结果，答案以具体数值形式给出（44.4 GPa），符合计算题的特征。 | 知识层次: 题目要求应用基本的弹性模量计算公式进行简单数值计算，属于直接套用公式和基本单位转换的应用层次，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算镁棒的弹性模量，只需应用胡克定律的基本公式（应力=弹性模量×应变），并进行简单的单位换算和数值代入即可得出结果。解题步骤直接且无需复杂的推导或组合多个公式，符合等级1的定义。", "convertible": true, "correct_option": "44.4 GPa", "choice_question": "A force of 20,000 N will cause a 1 cm × 1 cm bar of magnesium to stretch from 10 cm to 10.045 cm. The modulus of elasticity is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "44.4 GPa", "B": "88.8 GPa", "C": "22.2 GPa", "D": "66.6 GPa" }, "correct_answer": "A", "explanation": "正确答案A通过应力(20,000N/0.0001m²=200MPa)除以应变(0.045cm/10cm=0.0045)计算得出44.4GPa。干扰项B是正确答案的两倍，利用了AI可能错误地将原始长度加倍计算的认知偏差。干扰项C是正确答案的一半，针对可能错误地将应变减半的直觉陷阱。干扰项D是正确答案的1.5倍，针对可能混淆拉伸和剪切模量的多层次验证陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1613, "question": "Metallic bond", "answer": "The bonding force between metal atoms formed by the interaction between metal cations and free electrons is called metallic bond", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Metallic bond\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查金属键的基本定义和形成原理，属于基础概念的记忆和理解，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆金属键的基本定义，属于最基础的概念记忆层次。题目直接给出了金属键的明确定义，无需任何解释或分析步骤，符合选择题型中最简单的难度标准。", "convertible": true, "correct_option": "The bonding force between metal atoms formed by the interaction between metal cations and free electrons is called metallic bond", "choice_question": "Which of the following correctly describes a metallic bond?", "conversion_reason": "The answer is a standard definition of a metallic bond, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The bonding force between metal atoms formed by the interaction between metal cations and free electrons", "B": "The electrostatic attraction between fixed positive ions and delocalized valence electrons", "C": "A covalent-like bond formed by overlapping d-orbitals in transition metals", "D": "A hybrid bond combining ionic character from s-electron transfer and covalent character from p-orbital overlap" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines metallic bonding as the interaction between metal cations and delocalized electrons. Option B uses misleading terminology ('fixed' ions and 'valence' electrons) that contradicts the dynamic nature of metallic bonding. Option C introduces a transition metal-specific mechanism that doesn't apply universally. Option D creates a false hybrid concept by mixing ionic and covalent characteristics that don't exist in pure metallic bonds.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4081, "question": "Increasing the alumina \\left(\\mathrm{Al}_{2} \\mathrm{O}_{3}\\right) content of fireclays results in(a) an increase in maximum service temperature.(b) a decrease in maximum service temperature.", "answer": "Increasing the alumina \\left(\\mathrm{Al}_{2} \\mathrm{O}\\right)_{3} content of fireclays results in an increase in maximum service temperature.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(a)和(b)中选择正确答案 | 知识层次: 题目考查对氧化铝含量与耐火粘土最高使用温度关系的基础概念记忆，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即氧化铝含量增加对耐火粘土最高使用温度的影响。正确选项直接对应记忆性知识，无需复杂理解或分析步骤，属于简单概念识别。", "convertible": true, "correct_option": "an increase in maximum service temperature", "choice_question": "Increasing the alumina (Al₂O₃) content of fireclays results in", "conversion_reason": "原题目已经是选择题格式，且只有两个选项，可以明确识别出正确选项。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Enhanced creep resistance due to reduced grain boundary sliding", "B": "Decreased thermal shock resistance from higher thermal expansion mismatch", "C": "Improved electrical conductivity through increased electron mobility", "D": "Reduced oxidation resistance due to faster oxygen diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because alumina increases viscosity at high temperatures, inhibiting grain boundary sliding. B exploits thermal expansion intuition but ignores fireclay's inherent thermal shock resistance. C uses a plausible-sounding but irrelevant electron mobility concept. D reverses the actual effect of alumina as an oxygen diffusion barrier.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4083, "question": "As the porosity of refractory ceramic bricks increases, what happens to the strength?", "answer": "Strength decreases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释孔隙率增加对耐火陶瓷砖强度的影响，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对多孔耐火陶瓷砖强度与孔隙率关系的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即孔隙率增加对耐火陶瓷砖强度的影响。正确选项直接给出了明确的结论，无需进行复杂的概念解释或分析。因此，该题目在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "Strength decreases", "choice_question": "As the porosity of refractory ceramic bricks increases, what happens to the strength?", "conversion_reason": "The answer is a standard and concise statement that can be directly used as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Strength decreases due to reduced load-bearing cross-section", "B": "Strength increases as pores act as crack arrestors", "C": "Strength remains constant due to grain boundary strengthening", "D": "Strength initially increases then decreases (porosity-strength duality)" }, "correct_answer": "A", "explanation": "Correct answer A reflects the fundamental relationship where porosity reduces the effective load-bearing area. Option B exploits the crack arrestor misconception that applies to controlled porosity in some composites but not refractory bricks. Option C uses grain boundary strengthening which is irrelevant to porosity effects. Option D creates a false 'duality' concept that could mislead those familiar with other material property relationships.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2016, "question": "Calculate the distance between the center of a sodium ion and its nearest neighboring positive ion in NaCl (given the radii of Na+ and Cl− are 0.097nm and 0.181nm, respectively).", "answer": "0.393nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算钠离子与其最近邻正离子之间的距离），并给出了具体的离子半径数据。答案是一个具体的数值（0.393nm），需要通过公式应用和计算得出。 | 知识层次: 题目要求应用给定的离子半径数据进行简单计算，直接套用离子间距公式（半径相加），无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用给定的离子半径数据进行简单加法计算（Na+半径 + Cl−半径 = 0.097nm + 0.181nm = 0.278nm），然后乘以√2（因为NaCl晶体结构中最近邻正离子位于面心立方位置）得到最终距离0.393nm。整个过程仅涉及单一晶体学距离公式的直接套用，无需多步骤推导或复杂概念整合，属于最基础的计算类选择题。", "convertible": true, "correct_option": "0.393nm", "choice_question": "What is the distance between the center of a sodium ion and its nearest neighboring positive ion in NaCl (given the radii of Na+ and Cl− are 0.097nm and 0.181nm, respectively)?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.393nm", "B": "0.278nm", "C": "0.556nm", "D": "0.194nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.393nm) because in NaCl structure, the distance between two adjacent Na+ ions is the face diagonal of the unit cell, which is √2 times the nearest neighbor distance between Na+ and Cl− (0.097+0.181=0.278nm). Option B (0.278nm) is the Na+-Cl− distance, a common first-glance mistake. Option C (0.556nm) incorrectly uses double the unit cell edge length. Option D (0.194nm) is the sum of two Na+ radii, a misleading analogy to metallic bonding.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3558, "question": "In cubic crystals, the (110) and (211) planes belong to the same () zone.", "answer": "D", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从选项中选择正确答案，答案以选项形式给出（D） | 知识层次: 题目需要理解立方晶体中晶面属于同一晶带的条件，并应用晶带轴的概念进行分析。虽然不涉及复杂计算，但需要将多个概念关联起来进行判断，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，原因如下：", "convertible": true, "correct_option": "D", "choice_question": "In cubic crystals, the (110) and (211) planes belong to the same () zone.", "conversion_reason": "The original question is already in a multiple-choice format, making it convertible to a single-choice question by retaining the question stem and identifying the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[111] zone axis", "B": "[100] zone axis", "C": "[110] zone axis", "D": "[112] zone axis" }, "correct_answer": "D", "explanation": "The correct answer is D because the [112] direction is the common zone axis for both (110) and (211) planes in cubic crystals, as it satisfies the zone law (hu+kv+lw=0) for both planes. Option A is a strong distractor because [111] is a prominent direction in cubic systems but doesn't satisfy the zone condition for (110). Option B exploits the common misconception that low-index directions like [100] might be zone axes for multiple planes. Option C is particularly deceptive because it matches one of the plane indices, creating an intuitive but incorrect association.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3853, "question": "For an Fe-1.15% C alloy, determine the composition and amount of each phase present at 728 degrees C.", "answer": "Fe3C: 6.67% C, 6.4%; gamma: 0.77% C, 93.6%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算确定合金中各相的组成和含量，需要应用相图和相关公式进行计算，答案给出了具体的数值结果。 | 知识层次: 题目需要应用铁碳相图进行多步计算，包括确定相组成和相对量，涉及杠杆定律的应用和相图分析，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要考生掌握铁碳相图的基本概念（如Fe3C和gamma相的组成范围），能够正确识别728°C时的相平衡条件（共析反应温度），并应用杠杆定律进行两相组成和相对量的计算。虽然题目提供了正确选项可以部分验证计算过程，但仍需要考生完成多个步骤的推导和计算，属于综合性计算问题。", "convertible": true, "correct_option": "Fe3C: 6.67% C, 6.4%; gamma: 0.77% C, 93.6%", "choice_question": "For an Fe-1.15% C alloy, what is the composition and amount of each phase present at 728 degrees C?", "conversion_reason": "The answer is a specific and deterministic result, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fe3C: 6.67% C, 6.4%; gamma: 0.77% C, 93.6%", "B": "Fe3C: 6.67% C, 17.2%; gamma: 0.77% C, 82.8%", "C": "Fe3C: 6.67% C, 3.8%; gamma: 0.77% C, 96.2%", "D": "Fe3C: 6.67% C, 12.1%; gamma: 0.77% C, 87.9%" }, "correct_answer": "A", "explanation": "正确答案A通过杠杆定律精确计算得出。干扰项B错误地将碳含量直接用于相比例计算，忽略了合金整体成分。干扰项C基于错误的假设认为渗碳体比例应随温度降低而减少。干扰项D故意使用接近但错误的计算步骤，模拟常见的学生计算错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4760, "question": "Compute the modulus of elasticity for 15 vol% porosity given that the modulus of elasticity for spinel (MgAl2O4) having 5 vol% porosity is 240 GPa (35 x 10^6 psi).", "answer": "the modulus of elasticity for 15 vol% porosity is 195 gpa (28.4 x 10^6 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解15 vol%孔隙率下的弹性模量，答案也是一个具体的数值结果。 | 知识层次: 题目需要应用多步计算和公式推导，涉及孔隙率对弹性模量的影响分析，需要理解材料性能与孔隙率的关系并进行数值计算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解孔隙率对弹性模量的影响，并应用相关公式进行多步计算。题目要求从已知5%孔隙率的数据推导15%孔隙率的结果，涉及概念关联和综合分析能力，但作为选择题，正确选项的存在降低了部分解题难度。", "convertible": true, "correct_option": "195 GPa (28.4 x 10^6 psi)", "choice_question": "Given that the modulus of elasticity for spinel (MgAl2O4) with 5 vol% porosity is 240 GPa (35 x 10^6 psi), what is the modulus of elasticity for 15 vol% porosity?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "195 GPa (28.4 x 10^6 psi)", "B": "210 GPa (30.5 x 10^6 psi)", "C": "225 GPa (32.6 x 10^6 psi)", "D": "180 GPa (26.1 x 10^6 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the exponential porosity dependence relationship for ceramics (E = E0 * exp(-bP), where E0 is the zero-porosity modulus, b is a material constant, and P is porosity). Option B is designed to trap those who assume a linear relationship between porosity and modulus. Option C exploits confusion with shear modulus values for similar materials. Option D is a plausible but incorrect extrapolation from polymer porosity relationships, creating a cross-material-system intuition trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 875, "question": "What is the Kirkendall effect? Please explain it using diffusion theory.", "answer": "Kirkendall effect: In the diffusion process of substitutional solid solutions, markers placed at the original interface move towards the direction of the low-melting-point element, with the movement rate following a parabolic relationship with time. The Kirkendall effect negates the exchange mechanism of diffusion in substitutional solid solutions and confirms the vacancy mechanism; different components in the system have different partial diffusion coefficients. Relatively speaking, the low-melting-point component diffuses faster, while the high-melting-point component diffuses slower. This unequal atomic exchange results in the Kirkendall effect.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Kirkendall效应并用扩散理论进行说明，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目不仅要求解释Kirkendall效应的定义，还需要运用扩散理论进行深入分析，涉及不同组分的扩散系数差异、空位机制等复杂概念，并需要将这些概念关联起来进行综合解释。这需要较高的分析能力和对扩散机理的深入理解。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解Kirkendall效应的基本概念，还需要运用扩散理论进行机理深度解释，涉及多个复杂概念的综合运用（如置换固溶体、扩散机制、部分扩散系数等）。正确选项包含了对现象全面分析的要素（如标记移动方向与时间的关系、不同组元扩散速率的差异等），这远超选择题型通常考查的记忆或简单理解层面，需要考生具备高阶推理和分析能力。", "convertible": true, "correct_option": "Kirkendall effect: In the diffusion process of substitutional solid solutions, markers placed at the original interface move towards the direction of the low-melting-point element, with the movement rate following a parabolic relationship with time. The Kirkendall effect negates the exchange mechanism of diffusion in substitutional solid solutions and confirms the vacancy mechanism; different components in the system have different partial diffusion coefficients. Relatively speaking, the low-melting-point component diffuses faster, while the high-melting-point component diffuses slower. This unequal atomic exchange results in the Kirkendall effect.", "choice_question": "Which of the following best describes the Kirkendall effect?", "conversion_reason": "The answer is a standard explanation of the Kirkendall effect, which can be converted into a multiple-choice question format by presenting it as one of several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In substitutional diffusion, the faster-diffusing component creates excess vacancies that accumulate to form voids, while the slower-diffusing component's lattice contracts to maintain mass balance", "B": "The phenomenon where interstitial diffusion causes local lattice expansion due to size mismatch between solute and solvent atoms", "C": "A concentration-dependent diffusion process where the chemical potential gradient drives atoms to migrate against their concentration gradient", "D": "The observation that grain boundary diffusion always occurs faster than bulk diffusion at any given temperature" }, "correct_answer": "A", "explanation": "The Kirkendall effect specifically describes vacancy-mediated substitutional diffusion where unequal atomic fluxes cause marker movement and void formation. Option B incorrectly describes interstitial diffusion effects. Option C describes uphill diffusion, a separate phenomenon. Option D states a general diffusion rule unrelated to the Kirkendall effect. Advanced AIs might select B due to its plausible description of diffusion-induced strain, or D because of its correct but irrelevant statement about diffusion paths.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3813, "question": "Consider a Pb-35% Sn alloy. Determine the amounts and compositions of each microconstituent at 182°C.", "answer": "primary α: 19% sn, % primary α = 63%, eutectic: 61.9% sn, % eutectic = 37%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算确定Pb-35% Sn合金在182°C时各微组成物的量和组成，答案给出了具体的数值计算结果，涉及相图分析和百分比计算，属于典型的计算题。 | 知识层次: 题目需要应用相图知识进行多步计算，涉及相组成和成分的确定，需要综合分析Pb-Sn合金在特定温度下的相平衡状态，并运用杠杆法则进行计算。 | 难度: 在选择题中属于中等偏上难度，需要理解相图概念并进行多步计算。题目要求确定Pb-35% Sn合金在182°C时的各微组成物的含量和成分，这涉及：", "convertible": true, "correct_option": "primary α: 19% sn, % primary α = 63%, eutectic: 61.9% sn, % eutectic = 37%", "choice_question": "For a Pb-35% Sn alloy at 182°C, determine the amounts and compositions of each microconstituent:", "conversion_reason": "The answer is a specific set of values and compositions, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "primary α: 19% Sn, % primary α = 63%, eutectic: 61.9% Sn, % eutectic = 37%", "B": "primary α: 19% Sn, % primary α = 37%, eutectic: 61.9% Sn, % eutectic = 63%", "C": "primary α: 35% Sn, % primary α = 50%, eutectic: 61.9% Sn, % eutectic = 50%", "D": "primary α: 10% Sn, % primary α = 70%, eutectic: 50% Sn, % eutectic = 30%" }, "correct_answer": "A", "explanation": "The correct answer uses the lever rule calculations at 182°C for the Pb-Sn phase diagram. Option B reverses the percentages of primary α and eutectic, exploiting a common calculation reversal error. Option C incorrectly assumes the primary α composition equals the alloy composition, a typical oversimplification mistake. Option D uses arbitrary numbers that seem plausible but don't follow phase diagram rules, targeting intuitive but incorrect guesses.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 175, "question": "What is surface energy?", "answer": "Surface energy: Under constant temperature, pressure, and composition, the non-volume work required to reversibly increase the surface area of a substance is called surface energy; J/m2=N/m", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"surface energy\"进行定义和解释，答案提供了详细的文字描述和单位说明，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即表面能的定义和单位，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察对基础定义的理解和记忆，即表面能的定义及其单位。题目要求考生识别并选择正确的定义描述，无需进行复杂的分析或推理。因此，在选择题型内属于基本定义简答的难度等级。", "convertible": true, "correct_option": "Under constant temperature, pressure, and composition, the non-volume work required to reversibly increase the surface area of a substance is called surface energy; J/m2=N/m", "choice_question": "Which of the following correctly defines surface energy?", "conversion_reason": "The answer is a standard definition of a scientific term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Under constant temperature, pressure, and composition, the non-volume work required to reversibly increase the surface area of a substance; J/m2=N/m", "B": "The energy required to create new surfaces during fracture, equivalent to twice the surface tension", "C": "The excess energy at a crystal plane compared to bulk material, calculated as the derivative of Gibbs free energy with respect to area", "D": "The work needed to separate two bonded surfaces, equal to the integral of adhesion force over separation distance" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines surface energy with all thermodynamic conditions (constant T, P, composition) and specifies the correct units. Option B incorrectly conflates fracture surface energy with equilibrium surface energy. Option C describes surface free energy but omits the reversible work condition. Option D defines adhesion energy rather than intrinsic surface energy. These distractors exploit common conceptual overlaps in interfacial phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 886, "question": "A single crystal test bar of an FCC metal with a cross-sectional area of 10 cm² is subjected to a compression test along the axial direction. The critical resolved shear stress is known to be 0.1 kgf/mm², and the initial orientation of the bar axis is [215]. Please determine the initial slip system (specific indices are required).", "answer": "Initial slip system: (111)[011].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求确定初始滑移系统（需要具体的指数），这需要文字解释和论述，而不是简单的选择、判断或数值计算。 | 知识层次: 题目要求确定初始滑移系统，需要理解FCC金属的滑移系概念，并应用临界分切应力定律进行计算。这涉及到多步计算和概念关联，包括确定可能的滑移面和滑移方向，计算施密特因子，并选择具有最大分切应力的滑移系统。虽然不涉及复杂的推理分析或创新应用，但需要一定的综合分析能力。 | 难度: 在选择题型中，该题目属于较高难度，需要考生进行多步计算和综合分析。具体来说，考生需要：", "convertible": true, "correct_option": "(111)[011]", "choice_question": "A single crystal test bar of an FCC metal with a cross-sectional area of 10 cm² is subjected to a compression test along the axial direction. The critical resolved shear stress is known to be 0.1 kgf/mm², and the initial orientation of the bar axis is [215]. Which of the following is the initial slip system (specific indices are required)?", "conversion_reason": "The answer is a standard term (specific indices of the slip system), which can be presented as a choice among other plausible slip systems.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(111)[011]", "B": "(111)[101]", "C": "(111)[110]", "D": "(111)[112]" }, "correct_answer": "A", "explanation": "The correct slip system (111)[011] has the highest Schmid factor for the [215] orientation. Option B reverses the slip direction, which is a common mistake when visualizing FCC slip systems. Option C uses a non-close-packed direction, exploiting the misconception that any <110> direction could be active. Option D introduces a non-valid slip direction [112], which is a plausible-looking but incorrect combination that could trap those relying on pattern recognition rather than rigorous calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1992, "question": "If a piece of iron is heated to $850^{\\\\circ}\\\\mathrm{C}$ and then rapidly cooled to $20^{\\\\circ}\\\\mathrm{C}$, calculate how many times the number of vacancies should increase before and after the treatment (assuming the energy required to form one mole of vacancies in iron is 104600J)", "answer": "$0.616\\\\times10^{14}$ times", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算空位数量增加的倍数），需要使用公式（空位浓度公式）并给出具体数值结果 | 知识层次: 题目需要应用空位浓度公式进行多步计算，涉及温度变化对空位数量的影响，需要理解并关联热力学参数与材料微观结构变化的关系，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解空缺形成能的概念，掌握阿伦尼乌斯方程的应用，并进行多步计算（包括温度转换、指数运算等）。虽然题目提供了关键参数，但解题过程涉及综合分析和精确计算，属于典型的综合性计算问题。", "convertible": true, "correct_option": "$0.616\\times10^{14}$ times", "choice_question": "If a piece of iron is heated to $850^{\\circ}\\mathrm{C}$ and then rapidly cooled to $20^{\\circ}\\mathrm{C}$, how many times should the number of vacancies increase before and after the treatment (assuming the energy required to form one mole of vacancies in iron is 104600J)?", "conversion_reason": "The calculation question has a specific numerical answer, which can be directly used as the correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.616×10^14 times", "B": "1.24×10^12 times", "C": "3.08×10^13 times", "D": "2.47×10^11 times" }, "correct_answer": "A", "explanation": "The correct answer is A (0.616×10^14 times) calculated using the Arrhenius equation for vacancy concentration at two temperatures. Option B (1.24×10^12 times) is a common miscalculation from using incorrect Boltzmann constant units. Option C (3.08×10^13 times) results from mistakenly using the formation energy per vacancy instead of per mole. Option D (2.47×10^11 times) comes from incorrectly assuming linear temperature dependence of vacancy concentration.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3325, "question": "What are the types and characteristics of temper brittleness?", "answer": "There are mainly two types of temper brittleness, namely low-temperature temper brittleness and high-temperature temper brittleness. Low-temperature temper brittleness, also known as the first type of temper brittleness, occurs to varying degrees in almost all industrial steels and is independent of the cooling rate after tempering. Therefore, it is also called irreversible temper brittleness (i.e., it occurs whether cooled rapidly or slowly). High-temperature temper brittleness, also known as the second type of temper brittleness, is characterized by its occurrence only in steels with specific compositions. Whether temper brittleness occurs depends on the cooling rate after tempering, i.e., it appears with slow cooling after tempering but not with rapid cooling, hence it is also called reversible temper brittleness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述回火脆性的类型和特征，答案提供了详细的文字解释和分类说明，符合简答题的特点。 | 知识层次: 题目主要考查对回火脆性的类型和特点的记忆和理解，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生理解和描述两种回火脆性的类型及其特点，涉及概念的解释和描述，但不需要复杂的比较分析或深入的概念体系阐述。因此，属于中等难度。", "convertible": true, "correct_option": "There are mainly two types of temper brittleness, namely low-temperature temper brittleness and high-temperature temper brittleness. Low-temperature temper brittleness, also known as the first type of temper brittleness, occurs to varying degrees in almost all industrial steels and is independent of the cooling rate after tempering. Therefore, it is also called irreversible temper brittleness (i.e., it occurs whether cooled rapidly or slowly). High-temperature temper brittleness, also known as the second type of temper brittleness, is characterized by its occurrence only in steels with specific compositions. Whether temper brittleness occurs depends on the cooling rate after tempering, i.e., it appears with slow cooling after tempering but not with rapid cooling, hence it is also called reversible temper brittleness.", "choice_question": "Which of the following correctly describes the types and characteristics of temper brittleness?", "conversion_reason": "The answer is a standard explanation of the types and characteristics of temper brittleness, which can be converted into a multiple-choice question format by presenting the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Temper brittleness is classified into two types: low-temperature (irreversible) and high-temperature (reversible), with the former being cooling-rate independent and the latter occurring only in specific alloy compositions with cooling-rate dependence", "B": "All temper brittleness is reversible and can be eliminated by rapid cooling, with the distinction being only in the temperature range of occurrence (below 300°C vs above 500°C)", "C": "The primary classification is based on crystalline structure changes: body-centered cubic (BCC) steels exhibit type I brittleness while face-centered cubic (FCC) alloys show type II", "D": "Temper brittleness types are defined by chemical composition alone: carbon steels exhibit low-temperature brittleness while alloy steels exclusively show high-temperature brittleness" }, "correct_answer": "A", "explanation": "Option A correctly distinguishes the two types of temper brittleness with their key characteristics. Option B is incorrect because it falsely claims all temper brittleness is reversible. Option C uses crystalline structure as a misleading classification criterion. Option D oversimplifies the composition dependence, ignoring that alloy steels can exhibit both types.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1371, "question": "At what temperature or temperature range is secondary cementite formed, and through what reaction? Also, write the reaction equation.", "answer": "Secondary cementite: 1148~727°C, secondary precipitation reaction, γ→Fe3CII.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释二次渗碳体的形成温度范围、反应类型并写出反应方程式，需要文字解释和论述，符合简答题的特征。 | 知识层次: 题目主要考查对二次渗碳体形成温度范围及反应类型的记忆，以及反应方程式的书写，属于基础概念的记忆和理解层面。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确记忆并理解二次渗碳体的形成温度范围、反应类型以及反应方程式。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "1148~727°C, secondary precipitation reaction, γ→Fe3CII", "choice_question": "At what temperature or temperature range is secondary cementite formed, and through what reaction?", "conversion_reason": "The answer is a standard term and concept, which can be converted into a multiple-choice question format by presenting the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1148~727°C, secondary precipitation reaction, γ→Fe3CII", "B": "727°C, eutectoid reaction, γ→α+Fe3C", "C": "1495°C, peritectic reaction, δ+γ→α", "D": "912°C, polymorphic transformation, γ→α" }, "correct_answer": "A", "explanation": "The correct answer is A because secondary cementite (Fe3CII) forms during cooling from 1148°C to 727°C through a secondary precipitation reaction where cementite precipitates from austenite (γ). Option B is incorrect as it describes the eutectoid reaction forming pearlite, not secondary cementite. Option C is wrong as it describes a high-temperature peritectic reaction irrelevant to cementite formation. Option D is misleading as it describes the allotropic transformation of iron, unrelated to cementite precipitation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3481, "question": "Compare the properties of four alloy tool steels: 9SiCr, Cr12, 5CrMnMo, and W18Cr4V", "answer": "
Steel gradeProperties
9SiCrHigh strength and high wear resistance
Cr12High strength and high wear resistance
5CrMnMoBest comprehensive mechanical properties
W18Cr4VHigh strength and high wear resistance
", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求比较四种合金工具钢的性能，答案以表格形式呈现了每种钢的性能特点，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求比较四种合金工具钢的性能，需要理解每种钢的基本特性并进行综合分析。虽然不涉及复杂的计算或机理分析，但需要对不同材料的性能有一定的理解和关联，属于中等应用层次。 | 难度: 在选择题型中，该题目要求考生对四种合金工具钢（9SiCr、Cr12、5CrMnMo、W18Cr4V）的性能进行多角度比较和分析。虽然题目提供了正确选项，但考生需要具备较深的知识储备，能够理解并区分不同钢材的高强度、高耐磨性以及综合机械性能等特性。此外，题目涉及的知识层次为中等应用，要求考生进行多步计算、概念关联和综合分析，这在选择题型中属于较高难度的要求。因此，该题目在选择题型内属于等级4的难度。", "convertible": true, "correct_option": "5CrMnMo has the best comprehensive mechanical properties", "choice_question": "Which of the following alloy tool steels has the best comprehensive mechanical properties?", "conversion_reason": "The original question asks for a comparison of properties among four alloy tool steels, and the answer provides distinct properties for each. This can be converted into a multiple-choice question by focusing on one specific property and asking which steel has that property.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5CrMnMo", "B": "9SiCr", "C": "Cr12", "D": "W18Cr4V" }, "correct_answer": "A", "explanation": "5CrMnMo exhibits optimal balance of toughness, wear resistance, and thermal fatigue resistance due to its medium carbon content and Mn-Mo alloying. 9SiCr (B) has superior hardness but lower toughness, creating a cognitive bias toward 'harder is better'. Cr12 (C) leverages the common misconception that higher Cr content always improves properties, while actually being too brittle for general tool use. W18Cr4V (D) is a high-speed steel that appears superior due to its tungsten content, but its properties are specialized for high-temperature applications rather than comprehensive performance.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3892, "question": "Hafnium has six naturally occurring isotopes: 0.16% of { }^{174} Hf, with an atomic weight of 173.940 amu; 5.26% of { }^{176} Hf, with an atomic weight of 175.941 amu ; 18.60% of { }^{177} Hf, with an atomic weight of 176.943 amu ; 27.28% of { }^{178} Hf, with an atomic weight of 177.944 amu ; 13.62% of { }^{179} Hf, with an atomic weight of 178.946 amu;. and 35.08% of { }^{180} Hf, with an atomic weight of 179.947 amu. Calculate the average atomic weight of Hf. Give your answer to three decimal places.", "answer": "the average atomic weight of hf is 178.485 amu.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算（各同位素的原子质量与其丰度的加权平均）来求解铪的平均原子量，并给出了具体的计算步骤和精确到小数点后三位的要求。答案也是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目要求根据给定的同位素丰度和原子质量计算平均原子量，这属于基本公式应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然题目提供了多个同位素的数据，但计算平均原子重量的步骤是直接套用加权平均公式，不需要复杂的推理或多步骤计算。学生只需将各同位素的百分比乘以对应的原子质量，然后相加即可得到结果。因此，在选择题型内，这属于中等偏下的难度。", "convertible": true, "correct_option": "178.485 amu", "choice_question": "Hafnium has six naturally occurring isotopes with the following abundances and atomic weights: 0.16% of { }^{174} Hf (173.940 amu), 5.26% of { }^{176} Hf (175.941 amu), 18.60% of { }^{177} Hf (176.943 amu), 27.28% of { }^{178} Hf (177.944 amu), 13.62% of { }^{179} Hf (178.946 amu), and 35.08% of { }^{180} Hf (179.947 amu). What is the average atomic weight of Hf to three decimal places?", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "178.485 amu", "B": "178.492 amu", "C": "178.478 amu", "D": "178.501 amu" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算各同位素的加权平均得到的：0.0016×173.940 + 0.0526×175.941 + 0.1860×176.943 + 0.2728×177.944 + 0.1362×178.946 + 0.3508×179.947 = 178.485 amu。干扰项B是通过四舍五入中间计算步骤产生的误差；干扰项C是忽略了最低丰度的同位素贡献；干扰项D是错误地将百分比直接相加而非使用小数形式计算。这些干扰项利用了计算过程中常见的四舍五入错误和单位转换陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3384, "question": "What is the approximate quenching process in the manufacturing route of round dies made from 9SiCr steel?", "answer": "Quenching process: Heating temperature 850-870°C (oil quenching).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释具体的淬火工艺参数，答案以文字形式给出具体温度范围和淬火介质，属于需要文字解释的简答题类型 | 知识层次: 题目考查的是特定材料（9SiCr钢）在特定工艺（淬火）中的具体参数（加热温度850-870°C，油淬）的应用，属于直接套用工艺知识的简单应用层次，不需要复杂的计算或分析。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接套用已知的淬火工艺参数（850-870°C油淬）即可作答，无需复杂计算或概念分析。题目考察的是对基础工艺参数的记忆能力，符合等级2“简单应用过程描述”的标准。", "convertible": true, "correct_option": "Heating temperature 850-870°C (oil quenching)", "choice_question": "What is the approximate quenching process in the manufacturing route of round dies made from 9SiCr steel?", "conversion_reason": "The answer is a standard and specific process description, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Heating to 850-870°C followed by oil quenching", "B": "Heating to 780-800°C followed by water quenching", "C": "Heating to 920-940°C followed by air cooling", "D": "Heating to 1050-1070°C followed by polymer quenching" }, "correct_answer": "A", "explanation": "The correct answer is A because 9SiCr steel requires a heating temperature of 850-870°C for proper austenitization, followed by oil quenching to achieve the desired hardness while minimizing distortion. Option B is incorrect because the temperature is too low for complete austenitization and water quenching would cause excessive cracking. Option C is incorrect because the temperature is too high (risking grain growth) and air cooling is insufficient for hardening. Option D is incorrect because the temperature is far too high (causing severe grain coarsening) and polymer quenching is not standard for this steel grade.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 971, "question": "The interface between grains in single-phase metals or alloys is generally called grain boundaries, which are usually divided into two categories: low-angle grain boundaries and high-angle grain boundaries. What is the basis for this classification?", "answer": "The classification is based on the misorientation between the grains on either side of the boundary. Boundaries with a misorientation <15° are called low-angle grain boundaries, while those >15° are called high-angle grain boundaries.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释晶界分类的基础，答案提供了详细的文字解释和论述，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目考查对晶界分类的基本概念记忆和理解，仅需要回答分类依据的具体角度数值，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接询问了晶界分类的基础，正确选项明确给出了基于晶粒间取向差的角度划分标准（<15°为低角度晶界，>15°为高角度晶界）。这属于材料科学中最基础的概念记忆，无需复杂推理或跨概念整合，仅需识别并匹配定义即可作答。", "convertible": true, "correct_option": "The misorientation between the grains on either side of the boundary", "choice_question": "What is the basis for classifying grain boundaries into low-angle and high-angle grain boundaries?", "conversion_reason": "The answer is a standard concept and can be presented as a choice among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The misorientation angle between adjacent grains", "B": "The difference in elastic modulus across the boundary", "C": "The atomic density mismatch at the interface", "D": "The thermal expansion coefficient difference between grains" }, "correct_answer": "A", "explanation": "The correct answer is A because grain boundaries are classified based on the misorientation angle between adjacent grains, with low-angle boundaries typically having angles less than 10-15 degrees. Option B is a cognitive bias trap, as elastic modulus is a bulk property unrelated to boundary classification. Option C exploits the intuitive but incorrect notion that atomic density determines boundary type. Option D is a multi-level trap combining thermal properties with grain structure, which are unrelated to boundary classification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1527, "question": "Give examples of the basic strengthening forms of materials", "answer": "The basic strengthening forms of materials include: solid solution strengthening, strain hardening, precipitation strengthening and dispersion strengthening, grain refinement strengthening, etc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举材料的基本强化形式，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对材料强化基本形式的记忆和理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列举材料强化的基本形式，但正确选项已经提供了完整的分类体系（固溶强化、应变硬化、沉淀强化、弥散强化和晶粒细化强化等）。这需要考生对材料强化机制有较全面的概念性理解，而不仅仅是记忆单个定义。题目考察的是对\"基本强化形式\"这一分类体系的掌握程度，属于概念解释和描述的层次，但不需要进行复杂的比较分析或体系阐述。", "convertible": true, "correct_option": "solid solution strengthening, strain hardening, precipitation strengthening and dispersion strengthening, grain refinement strengthening", "choice_question": "Which of the following are the basic strengthening forms of materials?", "conversion_reason": "The answer is a list of standard terms and concepts related to material strengthening forms, which can be converted into a multiple-choice question format by presenting these terms as options and asking the examinee to select the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "solid solution strengthening", "B": "strain hardening", "C": "thermal expansion coefficient reduction", "D": "grain refinement strengthening" }, "correct_answer": "C", "explanation": "The correct answer is C because thermal expansion coefficient reduction is not a basic strengthening mechanism of materials, while the other options are. Option A exploits the common confusion between strengthening mechanisms and material properties. Option B is a legitimate strengthening mechanism but is included as a distractor. Option D is another legitimate strengthening mechanism, creating a high-difficulty choice between multiple correct-sounding options. The question specifically asks for basic strengthening forms, making thermal expansion coefficient reduction the clear outlier when analyzed carefully.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4196, "question": "Calculate the force of attraction between a K^{+}and an \\mathrm{O}^{2-} ion the centers of which are separated by a distance of 1.5nm.", "answer": "the force of attraction between the k^{+} and \\mathrm{o}^{2-} ions is 2.05 × 10^{-10} N.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算两个离子之间的吸引力，需要使用库仑定律等公式进行数值计算，答案是一个具体的数值结果。 | 知识层次: 题目要求使用库仑定律进行简单的数值计算，属于基本公式的直接应用，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算离子间的吸引力，只需要直接应用库仑定律公式F = k*q1*q2/r^2，代入给定的电荷值和距离即可得到结果。不需要额外的概念理解或复杂的计算步骤，属于最基础的应用题。", "convertible": true, "correct_option": "2.05 × 10^{-10} N", "choice_question": "What is the force of attraction between a K^{+} and an O^{2-} ion when their centers are separated by a distance of 1.5 nm?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.05 × 10^{-10} N", "B": "1.02 × 10^{-10} N", "C": "4.10 × 10^{-10} N", "D": "8.20 × 10^{-10} N" }, "correct_answer": "A", "explanation": "The correct answer is calculated using Coulomb's law considering the charges (+1e for K+ and -2e for O2-) and the distance (1.5 nm). Option B is half the correct value, exploiting the tendency to miscalculate charge magnitudes. Option C is double the correct value, playing on the common error of not properly accounting for the distance squared in the denominator. Option D is quadruple the correct value, targeting those who might confuse the exponent in the calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4897, "question": "What is the prime reason for fabricating laminar composites?", "answer": "These composites are constructed in order to have a relatively high strength in virtually all directions within the plane of the laminate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释层状复合材料制造的主要原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对层状复合材料基本概念的记忆和理解，即其制造的主要原因是为了在层压板平面内各个方向上具有相对较高的强度。这属于基础概念的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（层压复合材料的定义和基本原理），但正确选项需要考生理解并描述层压复合材料的主要优势（即在层压平面内各个方向上具有较高强度）。这比简单的定义记忆（等级1）要求更高，但不需要复杂的分析或比较（等级3）。因此，该题目属于等级2难度。", "convertible": true, "correct_option": "These composites are constructed in order to have a relatively high strength in virtually all directions within the plane of the laminate.", "choice_question": "What is the prime reason for fabricating laminar composites?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To achieve high strength in all directions within the plane of the laminate", "B": "To maximize the through-thickness thermal conductivity", "C": "To create anisotropic properties with maximum strength along the fiber direction", "D": "To minimize interfacial bonding strength between layers" }, "correct_answer": "A", "explanation": "The correct answer is A because laminar composites are specifically designed to distribute strength properties uniformly across the plane of the laminate. Option B is incorrect because through-thickness properties are typically sacrificed for in-plane performance. Option C describes unidirectional composites rather than laminar structures. Option D is the opposite of actual design goals, as strong interfacial bonding is crucial for load transfer between layers.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2062, "question": "Point out the errors in the following concept and correct them: (5) The so-called critical nucleus is the size of the embryo when the decrease in the system's free energy fully compensates for the increase in surface free energy.", "answer": "The decrease in the system's free energy should compensate for 2/3 of the surface free energy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目考查对临界核概念的基本理解和记忆，需要指出并纠正一个常见的概念错误，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生不仅知道临界核的定义，还需要理解自由能变化与表面自由能之间的具体补偿关系（2/3而非完全补偿）。这超出了简单的定义复述，要求对概念有更深入的理解和应用。", "convertible": true, "correct_option": "The decrease in the system's free energy should compensate for 2/3 of the surface free energy.", "choice_question": "Which of the following correctly describes the relationship between the decrease in the system's free energy and the surface free energy in the context of the critical nucleus?", "conversion_reason": "The original short answer question asks for a correction to a specific concept, which can be rephrased as a multiple-choice question by presenting the correct statement among possible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The decrease in the system's free energy should compensate for 2/3 of the surface free energy", "B": "The decrease in the system's free energy must exactly equal the surface free energy", "C": "The surface free energy must be twice the decrease in system's free energy", "D": "The decrease in system's free energy should be 1.5 times the surface free energy" }, "correct_answer": "A", "explanation": "The correct answer is A because the critical nucleus condition requires the free energy reduction to compensate for only 2/3 of the surface energy, not the full amount. Option B is a common misconception that appeals to intuitive energy balance. Option C reverses the correct relationship, exploiting confusion about energy ratios. Option D introduces a plausible but incorrect multiplier factor that might seem reasonable for nucleation calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 323, "question": "How to increase the number of dislocations?", "answer": "The number of dislocations can be increased by large deformation methods.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释如何增加位错数量，答案提供了简短的论述而非选择、判断或计算。 | 知识层次: 题目考查的是关于位错数量增加的基本方法，属于基础概念的记忆和理解范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即\"如何增加位错数量\"这一简单事实。正确选项直接给出了答案（大变形方法），不需要任何解释或推理过程。这属于最基本的概念记忆题，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Large deformation methods", "choice_question": "Which of the following methods can increase the number of dislocations?", "conversion_reason": "The answer is a standard method or concept, which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Applying high-temperature annealing above the recrystallization temperature", "B": "Subjecting the material to cyclic loading below the yield strength", "C": "Performing rapid quenching from the solution treatment temperature", "D": "Introducing coherent precipitates through aging treatment" }, "correct_answer": "B", "explanation": "The correct answer is B because cyclic loading below the yield strength can introduce dislocations through fatigue mechanisms, even without macroscopic plastic deformation. Option A is incorrect because annealing typically reduces dislocation density through recovery and recrystallization. Option C is a trap for those who associate quenching with defects, but it primarily introduces point defects rather than dislocations. Option D exploits the common misconception that all precipitates increase dislocations, while coherent precipitates actually reduce strain fields and may decrease dislocation density.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1258, "question": "What is the kinking mechanism in the analysis of the mechanisms and manifestations of plastic deformation in materials?", "answer": "When a crystal can neither slip nor undergo twinning, it can undergo plastic deformation through kinking. Its characteristic is that the orientation of the kinked crystal undergoes asymmetric changes. The dislocation mechanism refers to the process where, during plastic deformation, edge dislocations of the same sign accumulate in other regions due to dislocation motion. The convergence of dislocations generates bending stress, causing the crystal lattice to bend and kink, thereby forming a kinked region.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释kinking机制在材料塑性变形中的作用和表现，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释塑性变形中的kinking机制，涉及位错运动、应力分布和晶体取向变化等多个复杂概念的综合分析，需要深入理解并关联多个知识点进行推理和解释。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求深入理解晶体塑性变形的复杂机制，包括滑移、孪生和扭折等变形方式的区别，以及位错运动、积累和应力产生的详细过程。正确选项不仅需要识别扭折变形的特征，还需要解释位错机制如何导致晶格弯曲和扭折区域的形成。这要求考生具备综合运用材料科学知识、进行推理分析和机理解释的能力，属于复杂现象的全面分析层次。", "convertible": true, "correct_option": "When a crystal can neither slip nor undergo twinning, it can undergo plastic deformation through kinking. Its characteristic is that the orientation of the kinked crystal undergoes asymmetric changes. The dislocation mechanism refers to the process where, during plastic deformation, edge dislocations of the same sign accumulate in other regions due to dislocation motion. The convergence of dislocations generates bending stress, causing the crystal lattice to bend and kink, thereby forming a kinked region.", "choice_question": "What is the kinking mechanism in the analysis of the mechanisms and manifestations of plastic deformation in materials?", "conversion_reason": "The answer is a standard explanation of the kinking mechanism, which can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A localized lattice rotation mechanism where edge dislocations of the same sign accumulate, generating bending stress that forms asymmetric kink bands", "B": "A twinning-like deformation mode where symmetric lattice reorientation occurs through coordinated dislocation motion", "C": "A stress-induced phase transformation mechanism that creates zigzag patterns in the crystal structure", "D": "A grain boundary sliding process that accommodates strain through localized shear band formation" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the dislocation-mediated kinking mechanism where asymmetric lattice rotation occurs. Option B is a cognitive bias trap - it describes twinning rather than kinking, exploiting the common confusion between these two deformation modes. Option C is a professional intuition trap, using phase transformation terminology that sounds plausible but is irrelevant to kinking. Option D is a multi-level verification trap, combining grain boundary sliding (a real phenomenon) with shear bands to create a superficially convincing but incorrect mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2865, "question": "After cold working, the dislocation density of $\\\\mathbf{A}\\\\mathbf{g}$ is $10^{12}/\\\\mathfrak{c m}^{2}$. Assuming that the recrystallization nucleus moves from a high-angle grain boundary into the deformed matrix, find the minimum radius of curvature for the bulging grain boundary $\\\\scriptstyle\\\\left(\\\\mathbf{A}\\\\mathbf{g}_{:}G=30\\\\mathrm{GPa},b=0.3\\\\mathrm{nm},\\\\gamma=0.4\\\\mathrm{J}/\\\\mathrm{m}^{2}\\\\right)$.", "answer": "The driving force $F$ for the movement of the $\\\\mathbf{Ag}$ recrystallization nucleus from a high-angle grain boundary into the deformed matrix is the stored energy from cold working, $F= G b^{2}\\\\left(\\\\rho_{1}-\\\\rho_{0}\\\\right)$. Since $\\\\rho_{1}\\\\gg\\\\rho_{0}$, $\\\\scriptstyle{F\\\\approx G b^{2}\\\\rho_{1}}$. The bulged grain boundary is subjected to a force $f$ directed toward its center of curvature. When the radius of curvature of the bulge is $R$, $f= \\\\frac{2\\\\gamma}{R},f$ $\\\\scriptstyle{\\\\dot{F}}$ $R_{\\\\mathrm{min}}$ $f$ $F$ $$F{=}f,$$$$G\\\\delta^{2}\\\\rho_{\\\\mathrm{f}}=\\\\frac{2\\\\gamma}{R_{\\\\mathrm{rein}}}$$$$R_{\\\\mathrm{aia}}={\\\\frac{2\\\\gamma}{G b^{2}\\\\rho_{1}}}={\\\\frac{2\\\\times0.4}{30\\\\times10^{8}\\\\times(3\\\\times10^{-10})^{2}\\\\times10^{16}}}=2.9\\\\times10^{-8}({\\\\mathrm{m}})=29({\\\\mathrm{nm}})$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解最小曲率半径，答案中包含了具体的计算步骤和最终数值结果。 | 知识层次: 题目涉及多步计算和概念关联，需要理解冷加工后的位错密度、再结晶核的形成以及晶界弯曲的力学平衡等概念，并应用相关公式进行计算。虽然题目提供了必要的参数和公式，但需要综合运用这些知识来解决问题，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如位错密度、再结晶驱动力、晶界曲率半径等）并进行多步计算。题目要求将理论公式与给定参数结合，推导出最小曲率半径，涉及综合性计算和概念关联。虽然题目提供了所有必要参数，但解题步骤较为复杂，需要较强的综合分析能力。", "convertible": true, "correct_option": "29 nm", "choice_question": "After cold working, the dislocation density of $\\mathbf{A}\\mathbf{g}$ is $10^{12}/\\mathfrak{c m}^{2}$. Assuming that the recrystallization nucleus moves from a high-angle grain boundary into the deformed matrix, the minimum radius of curvature for the bulging grain boundary is: ($\\mathbf{A}\\mathbf{g}_{:}G=30\\mathrm{GPa},b=0.3\\mathrm{nm},\\gamma=0.4\\mathrm{J}/\\mathrm{m}^{2}$)", "conversion_reason": "The calculation yields a specific numerical answer (29 nm), which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "29 nm", "B": "58 nm", "C": "14.5 nm", "D": "43.5 nm" }, "correct_answer": "A", "explanation": "正确答案A基于公式r=γ/(τb)，其中τ=0.5Gb√ρ。计算得到τ=0.5×30GPa×0.3nm×√(10^12/cm²)=4.5MPa，因此r=0.4J/m²/(4.5MPa×0.3nm)=29nm。干扰项B是正确答案的2倍，利用了剪切模量G与弹性模量E的混淆；干扰项C是正确答案的一半，基于常见的一半经验值陷阱；干扰项D是正确答案的1.5倍，利用了材料科学中常见的1.5倍安全系数直觉。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1074, "question": "Non-steady state diffusion", "answer": "Non-steady state diffusion: diffusion where both the concentration gradient and the diffusion flux vary with time and distance.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Non-steady state diffusion\"进行文字解释和论述，答案是一个定义性的描述，不需要计算或选择，符合简答题的特征。 | 知识层次: 题目考查非稳态扩散的基本定义，属于基础概念的记忆和理解，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆，但要求考生不仅记住定义，还需要理解非稳态扩散中浓度梯度和扩散通量随时间距离变化的关系。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Non-steady state diffusion: diffusion where both the concentration gradient and the diffusion flux vary with time and distance.", "choice_question": "下列关于Non-steady state diffusion的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Non-steady state diffusion: diffusion where both the concentration gradient and the diffusion flux vary with time and distance", "B": "Non-steady state diffusion occurs when the diffusion coefficient is time-dependent, while the concentration gradient remains constant", "C": "Non-steady state diffusion is characterized by a linear concentration profile that shifts uniformly with time", "D": "In non-steady state diffusion, the flux remains constant while the concentration gradient changes with position" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines non-steady state diffusion where both concentration gradient and flux vary with time and distance. Option B is a cognitive bias trap - it incorrectly suggests the gradient remains constant while only the coefficient changes. Option C exploits professional intuition by describing what appears to be a plausible time-dependent profile but is actually characteristic of steady-state. Option D creates a multi-level verification trap by reversing the correct relationship between flux and gradient.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2806, "question": "In NiO, introducing high-valence W6+, how many vacancies will each W6+ generate?", "answer": "Each W6+ introduction generates 2 Ni2+ vacancies.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释高价位W6+引入NiO中会产生多少个空位，答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要理解高价位掺杂对NiO中空位形成的影响，涉及电荷平衡和缺陷化学的基本原理，需要进行多步推理和计算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解NiO中掺杂高价态W6+的电荷补偿机制，并能够正确计算生成的Ni2+空位数量。题目涉及多步计算和概念关联，但选项已经给出了明确的计算结果，降低了部分难度。", "convertible": true, "correct_option": "2 Ni2+ vacancies", "choice_question": "In NiO, introducing high-valence W6+, how many vacancies will each W6+ generate?", "conversion_reason": "The answer is a specific and standard term (2 Ni2+ vacancies), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2 Ni2+ vacancies", "B": "1 Ni2+ vacancy", "C": "3 O2- vacancies", "D": "1 O2- vacancy" }, "correct_answer": "A", "explanation": "The correct answer is A because introducing W6+ into NiO (where Ni is in +2 oxidation state) requires charge compensation. Each W6+ replaces one Ni2+, creating a +4 excess charge. To maintain charge neutrality, two Ni2+ vacancies are generated (each contributing -2 charge). Option B is a cognitive bias trap - it seems plausible for simple substitution but ignores the full charge balance requirement. Option C exploits confusion between cation and anion vacancies, while Option D is a common mistake from oversimplifying defect chemistry calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3772, "question": "Liquid magnesium is poured into a 2 cm × 2 cm × 24 cm mold and, as a result of directional solidification, all of the solidification shrinkage occurs along the length of the casting. Determine the length of the casting immediately after solidification is completed.", "answer": "the length of the casting immediately after solidification is completed is 23.04 cm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定铸件凝固后的长度。答案是一个具体的数值结果，表明需要通过计算得出。 | 知识层次: 题目涉及基本的体积收缩计算和简单的公式应用，不需要多步计算或复杂的概念关联，属于直接套用基本知识的简单应用。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（收缩率计算）并进行简单计算即可得出答案。题目明确给出了所有必要的信息，且解题步骤非常直接，无需组合多个公式或进行复杂分析。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "23.04 cm", "choice_question": "Liquid magnesium is poured into a 2 cm × 2 cm × 24 cm mold and, as a result of directional solidification, all of the solidification shrinkage occurs along the length of the casting. What is the length of the casting immediately after solidification is completed?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "23.04 cm", "B": "23.52 cm", "C": "22.56 cm", "D": "24.00 cm" }, "correct_answer": "A", "explanation": "The correct answer is A (23.04 cm) because magnesium has a solidification shrinkage of 4%, so the length reduction is 24 cm × 0.04 = 0.96 cm, resulting in 23.04 cm. Option B (23.52 cm) uses half the correct shrinkage percentage (2%), a common error when confusing with thermal contraction. Option C (22.56 cm) incorrectly applies the shrinkage to both length and cross-section. Option D (24.00 cm) ignores shrinkage entirely, a trap for those not considering directional solidification effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 13, "question": "When n equal-sized spheres are closely packed, how many tetrahedral voids and octahedral voids can be formed?", "answer": "When n equal-sized spheres are closely packed, 2n tetrahedral voids and n octahedral voids can be formed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述在紧密堆积情况下形成的四面体空隙和八面体空隙的数量，答案需要文字描述而非选择、判断或计算。 | 知识层次: 题目考查对紧密堆积中空隙类型和数量的基本概念记忆，属于定义和基本原理的记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生掌握紧密堆积中四面体空隙和八面体空隙的数量关系，这比单纯记忆定义或分类要复杂一些。题目要求考生理解并应用基本原理，而不仅仅是简单的定义回忆。因此，在选择题型内，该题目属于等级2的难度。", "convertible": true, "correct_option": "2n tetrahedral voids and n octahedral voids", "choice_question": "When n equal-sized spheres are closely packed, how many tetrahedral voids and octahedral voids can be formed?", "conversion_reason": "The answer is a specific and standard concept in the field of material science or chemistry, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2n tetrahedral voids and n octahedral voids", "B": "n tetrahedral voids and 2n octahedral voids", "C": "n tetrahedral voids and n octahedral voids", "D": "4n tetrahedral voids and 2n octahedral voids" }, "correct_answer": "A", "explanation": "The correct answer is A because in close packing of n equal-sized spheres, each sphere is surrounded by 12 neighbors creating 2n tetrahedral voids (each tetrahedral void is formed by 4 spheres) and n octahedral voids (each octahedral void is formed by 6 spheres). Option B reverses the counts, exploiting the common confusion between the two types of voids. Option C suggests equal numbers, appealing to the false intuition that voids should be equally distributed. Option D doubles the correct counts, targeting those who might incorrectly extrapolate from unit cell calculations to the entire packing structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1952, "question": "What are the common phase structures in solids?", "answer": "The common phase structures in solids include: solid solution (element), compound, ceramic crystalline phase, amorphous phase, and molecular phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举和解释常见的固相结构类型，答案以文字解释和论述的形式呈现，没有提供选项或要求进行判断或计算。 | 知识层次: 题目考查对固体中常见相结构的基本概念的记忆和理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生掌握并区分多种不同的固体相结构（如固溶体、化合物、陶瓷晶相等），这比单纯记忆单个定义要复杂。题目不涉及复杂的概念体系阐述或深入分析，但要求对多个相关概念有清晰的理解和分类能力，因此属于等级2难度。", "convertible": true, "correct_option": "solid solution (element), compound, ceramic crystalline phase, amorphous phase, and molecular phase", "choice_question": "Which of the following lists includes all the common phase structures in solids?", "conversion_reason": "The answer is a list of standard terms or concepts, which can be converted into a multiple-choice question format by presenting these terms as options and asking the examinee to select the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "solid solution (element), compound, ceramic crystalline phase, amorphous phase, and molecular phase", "B": "single crystal, polycrystal, amorphous, and quasicrystal", "C": "ionic, covalent, metallic, and molecular bonding types", "D": "BCC, FCC, HCP, and simple cubic crystal structures" }, "correct_answer": "A", "explanation": "The correct answer A lists all fundamental phase structure categories in solids. Option B confuses phase structures with microstructural classifications (cognitive bias). Option C substitutes bonding types for phase structures (intuition trap). Option D provides common crystal structures but misses non-crystalline phases (multi-level verification trap). Advanced AIs may incorrectly select B due to its apparent completeness in describing solid states.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3649, "question": "BCC lithium has a lattice parameter of 3.5089 × 10^-8 cm and contains one vacancy per 200 unit cells. Calculate the number of vacancies per cubic centimeter.", "answer": "1.157 × 10^20 vacancies/cm³", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算空位浓度），需要应用公式和单位转换，最终给出具体数值答案。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过已知的晶格参数和空位数量计算单位体积内的空位数。虽然需要理解BCC结构和空位的概念，但计算过程相对直接，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解BCC结构的基本概念和单位晶胞的体积计算，但解题步骤相对直接：首先计算单位晶胞的体积，然后根据给定的空位比例计算每立方厘米的空位数。主要涉及基本公式的直接套用和简单计算，不需要复杂的推导或多步骤组合。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "1.157 × 10^20 vacancies/cm³", "choice_question": "BCC lithium has a lattice parameter of 3.5089 × 10^-8 cm and contains one vacancy per 200 unit cells. The number of vacancies per cubic centimeter is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.157 × 10^20 vacancies/cm³", "B": "2.314 × 10^20 vacancies/cm³", "C": "5.785 × 10^19 vacancies/cm³", "D": "4.628 × 10^20 vacancies/cm³" }, "correct_answer": "A", "explanation": "The correct answer A is calculated by first determining the volume of a unit cell (a^3 = (3.5089 × 10^-8 cm)^3 = 4.319 × 10^-23 cm³), then calculating the number of unit cells per cm³ (1/4.319 × 10^-23 = 2.314 × 10^22 cells/cm³), and finally dividing by 200 to get vacancies. Option B is a trap for those who forget to divide by 200 (using all unit cells as vacancies). Option C is half the correct value, exploiting common calculation halving errors. Option D is double the correct value, targeting those who might confuse vacancy concentration with defect pairs.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2804, "question": "Introducing high-valence W6+ into NiO will generate vacancies of which ions?", "answer": "Vacancies of cations (Ni) will be generated. (Principle of electroneutrality)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要解释引入高价位W6+对NiO中离子空位的影响，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解电中性原理并应用到具体材料体系中，涉及多价态离子掺杂对缺陷类型的影响分析，属于概念关联和中等复杂度的应用分析。 | 难度: 在选择题中属于中等难度，需要理解电中性原则和离子价态变化对缺陷形成的影响，并进行综合分析。题目要求考生将高价位W6+引入NiO的概念与阳离子空位生成联系起来，这需要多步概念关联和中等程度的综合分析能力。", "convertible": true, "correct_option": "Vacancies of cations (Ni) will be generated.", "choice_question": "Introducing high-valence W6+ into NiO will generate vacancies of which ions?", "conversion_reason": "The answer is a standard statement that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Vacancies of Ni2+ ions", "B": "Vacancies of O2- ions", "C": "Interstitial W6+ ions", "D": "Both Ni2+ and O2- vacancies" }, "correct_answer": "A", "explanation": "The correct answer is A because introducing high-valence W6+ into NiO creates cation (Ni2+) vacancies to maintain charge neutrality. Option B is a cognitive bias trap, as oxygen vacancies are common in oxides but incorrect here. Option C exploits the intuition that high-valence dopants might occupy interstitial sites. Option D is a multi-level verification trap, combining two plausible but incorrect mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2156, "question": "When a tensile force is applied along the [0001] direction of a hexagonal close-packed single crystal, what are the possible deformations and the primary mode of deformation?", "answer": "The slip plane of hexagonal close-packed metals is (0001), and the resolved shear stress on the slip plane in the [0001] direction is zero, so the single crystal cannot slip. During tension, the possible deformations of the single crystal are elastic deformation or subsequent brittle fracture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释可能的变形和主要变形模式，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要理解六方密堆积单晶的滑移面和方向，并分析在特定方向施加拉力时的变形机制。这涉及到对晶体结构、滑移系统和应力分解的综合理解，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，原因如下：", "convertible": true, "correct_option": "The slip plane of hexagonal close-packed metals is (0001), and the resolved shear stress on the slip plane in the [0001] direction is zero, so the single crystal cannot slip. During tension, the possible deformations of the single crystal are elastic deformation or subsequent brittle fracture.", "choice_question": "When a tensile force is applied along the [0001] direction of a hexagonal close-packed single crystal, what are the possible deformations and the primary mode of deformation?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Elastic deformation followed by brittle fracture due to zero resolved shear stress on the (0001) slip plane", "B": "Plastic deformation via prismatic slip systems with Burgers vector [1120]", "C": "Twinning deformation on {1012} planes due to high critical resolved shear stress", "D": "Dislocation climb-assisted plasticity at elevated temperatures" }, "correct_answer": "A", "explanation": "The correct answer is A because the [0001] direction is parallel to the c-axis in HCP crystals, making the resolved shear stress zero on the basal (0001) slip plane. This prevents conventional slip deformation. Option B is incorrect because prismatic slip would require non-zero resolved shear stress along [0001]. Option C is a common misconception as twinning requires specific stress conditions not met here. Option D describes a high-temperature mechanism irrelevant to the question's scope.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 602, "question": "When a disordered solid solution transforms into an ordered solid solution, the general trend in the changes of alloy properties is that strength and hardness", "answer": "increase", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释有序固溶体转变对合金性能的影响趋势，答案需要文字描述（increase），属于简答题类型。 | 知识层次: 题目考查对有序固溶体转变后合金性能变化的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目属于基础概念记忆层次，仅需记住有序固溶体转变后强度和硬度的一般变化趋势即可作答。题目直接给出正确选项，无需复杂推理或概念比较，属于最基本的选择题难度。", "convertible": true, "correct_option": "increase", "choice_question": "When a disordered solid solution transforms into an ordered solid solution, the general trend in the changes of alloy properties is that strength and hardness:", "conversion_reason": "The answer is a standard term and can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increase due to the formation of superlattice structures that impede dislocation motion", "B": "Decrease because ordered arrangements reduce lattice distortion energy", "C": "Remain unchanged as the overall composition stays constant", "D": "First decrease then increase due to competing effects of ordering and recrystallization" }, "correct_answer": "A", "explanation": "The correct answer is A because ordering creates periodic potential barriers (superlattice structures) that significantly hinder dislocation movement, increasing strength. Option B exploits the misconception that reduced lattice distortion would lower strength, ignoring the dominant effect of dislocation pinning. Option C targets the common oversight that composition alone determines mechanical properties. Option D introduces a plausible-sounding but non-existent two-stage process to trap those considering kinetic effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3069, "question": "Why is the tensile strength of ceramics often much lower than the theoretical strength?", "answer": "Due to the splitting effect of pores and stress concentration during tension, the tensile strength of ceramics is lower than the theoretical strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么陶瓷的抗拉强度通常远低于理论强度，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要解释陶瓷材料拉伸强度低于理论强度的原因，涉及孔隙效应和应力集中等复杂机理的分析，需要综合运用材料科学知识进行推理和解释。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅理解陶瓷材料的基本性能特点，还需要掌握孔隙和应力集中对材料强度影响的机理。正确选项涉及对复杂现象（孔隙分裂效应和应力集中）的综合分析，需要考生具备将理论知识应用于具体材料性能解释的能力。这超出了简单记忆或基础理解的范畴，属于需要机理深度解释的题目类型。", "convertible": true, "correct_option": "Due to the splitting effect of pores and stress concentration during tension, the tensile strength of ceramics is lower than the theoretical strength.", "choice_question": "Why is the tensile strength of ceramics often much lower than the theoretical strength?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Due to the splitting effect of pores and stress concentration during tension", "B": "Because ceramics primarily fail through dislocation motion like metals", "C": "Due to their high thermal expansion coefficient causing microcracks", "D": "Because their covalent bonds are weaker than metallic bonds under tension" }, "correct_answer": "A", "explanation": "Correct answer A addresses the actual micromechanical failure mechanisms in ceramics. Option B exploits confusion with metallic behavior, where dislocations are indeed the primary failure mechanism. Option C uses a partially correct fact (thermal expansion can cause microcracks) but misapplies it to tensile strength. Option D creates a false comparison between bond types, ignoring that covalent bonds are actually stronger but ceramics fail due to defect propagation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 284, "question": "Analyze the effect of component changes on the driving force of solid-state phase transformation", "answer": "The driving force for phase transformation is the difference in volume free energy between the new and old phases at the phase transition temperature (ΔG̃τ), and ΔG<0 is a necessary condition for the formation of the new phase. When two components mix to form a solid solution, the free energy of the mixed system changes. The magnitude of the driving force for phase transformation can be determined through the free energy-composition curve.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析成分变化对固态相变驱动力的影响，答案提供了详细的文字解释和论述，没有涉及选择题、判断题或计算题的特征。 | 知识层次: 题目要求分析组分变化对固态相变驱动力的影响，涉及自由能-成分曲线的理解和应用，需要综合运用热力学原理和相变理论进行推理分析，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解固态相变驱动力的基本概念（ΔG̃τ和ΔG<0的必要条件），还需要掌握自由能-成分曲线的分析方法，并能综合运用这些知识来判断组分变化对相变驱动力的影响。这涉及到复杂的热力学原理和相图分析能力，需要考生具备深度的机理理解和综合推理能力，属于选择题型中对知识掌握深度和综合分析能力要求最高的类型。", "convertible": true, "correct_option": "The driving force for phase transformation is the difference in volume free energy between the new and old phases at the phase transition temperature (ΔG̃τ), and ΔG<0 is a necessary condition for the formation of the new phase. When two components mix to form a solid solution, the free energy of the mixed system changes. The magnitude of the driving force for phase transformation can be determined through the free energy-composition curve.", "choice_question": "Which of the following correctly describes the effect of component changes on the driving force of solid-state phase transformation?", "conversion_reason": "The answer is a standard explanation of the concept, which can be converted into a multiple-choice question by presenting it as the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The driving force increases linearly with solute concentration due to enhanced chemical potential gradients", "B": "The driving force is solely determined by the enthalpy difference between phases, independent of composition", "C": "Adding solute always decreases the driving force by stabilizing the parent phase through solid solution strengthening", "D": "The maximum driving force occurs at the eutectic composition where liquid and solid free energy curves intersect" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental relationship where chemical potential gradients created by solute addition provide the thermodynamic driving force. Option B is a common oversimplification that ignores compositional effects on free energy. Option C exploits the misconception that strengthening always reduces transformation tendency. Option D strategically confuses eutectic reaction conditions with general solid-state transformation thermodynamics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4726, "question": "For an ASTM grain size of 6, approximately how many grains would there be per square inch without any magnification?", "answer": "320000 grains/in.^2", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过计算得出具体的数值结果（320000 grains/in.^2），涉及ASTM晶粒尺寸标准的公式应用，属于典型的计算题。 | 知识层次: 题目考查ASTM晶粒度标准的基本公式应用，仅需直接套用公式N=2^(n-1)进行计算，属于单一知识点、单步计算的简单应用。 | 难度: 在选择题型中，该题目仅需直接应用ASTM晶粒度计算公式，无需复杂步骤或多公式组合。属于单一公式直接计算的简单应用，符合等级1的标准。", "convertible": true, "correct_option": "320000 grains/in.^2", "choice_question": "For an ASTM grain size of 6, approximately how many grains would there be per square inch without any magnification?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "320000 grains/in.^2", "B": "160000 grains/in.^2", "C": "640000 grains/in.^2", "D": "80000 grains/in.^2" }, "correct_answer": "A", "explanation": "The correct answer is A (320000 grains/in.^2) because the ASTM grain size number (n) is related to the number of grains per square inch (N) by the formula N = 2^(n-1) * 1000. For n=6, this gives N = 2^5 * 1000 = 320000. Option B (160000) is a common mistake from using n-2 instead of n-1 in the exponent. Option C (640000) results from incorrectly doubling the correct value. Option D (80000) comes from misapplying the formula as N = 2^(n-3) * 1000.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4592, "question": "For aluminum, the heat capacity at constant volume Cv at 30 K is 0.81 J/mol-K, and the Debye temperature is 375 K. Estimate the specific heat at 425 K.", "answer": "the specific heat at 425 K is 923 J/kg-K.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及热容量的估算和单位转换，答案是一个具体的数值结果。 | 知识层次: 题目需要应用德拜模型和热容公式进行多步计算，涉及概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解德拜温度的概念，掌握热容随温度变化的规律，并进行多步计算。题目涉及从已知的低温热容数据推导高温下的热容，需要综合运用德拜模型和经典热容理论，属于综合性计算问题。", "convertible": true, "correct_option": "923 J/kg-K", "choice_question": "For aluminum, the heat capacity at constant volume Cv at 30 K is 0.81 J/mol-K, and the Debye temperature is 375 K. Estimate the specific heat at 425 K.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "923 J/kg-K", "B": "0.81 J/mol-K", "C": "1.12 kJ/kg-K", "D": "24.2 J/mol-K" }, "correct_answer": "A", "explanation": "The correct answer is A (923 J/kg-K) because it properly converts the molar heat capacity to specific heat using aluminum's molar mass (26.98 g/mol) and accounts for the temperature exceeding the Debye temperature where Cv approaches the Dulong-Petit limit. Option B is a cognitive bias trap - using the given low-temperature Cv value without conversion or consideration of temperature effects. Option C exploits unit confusion by presenting a plausible-looking value in wrong units. Option D is a professional intuition trap - providing a value that seems reasonable for intermediate temperatures but fails to account for the high-temperature regime.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2447, "question": "When using X-ray detection, how does the diffraction of polycrystalline texture appear?", "answer": "The diffraction of polycrystalline texture appears as the diffraction rings of polycrystals becoming discontinuous rings, and in extreme cases, turning into diffraction spots like those of single crystals.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要解释X射线检测中多晶织构的衍射表现，答案以文字形式详细描述了衍射环的变化情况，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目需要理解多晶织构在X射线衍射中的表现，并解释衍射环不连续甚至变成单晶衍射点的现象。这涉及对多晶和单晶衍射原理的综合理解，以及织构对衍射图案影响的分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解X射线衍射的基本原理以及多晶和单晶衍射的区别，并能综合分析多晶织构衍射的特殊表现。虽然题目提供了正确选项，但需要考生具备一定的知识背景才能准确理解并选择正确答案。", "convertible": true, "correct_option": "The diffraction of polycrystalline texture appears as the diffraction rings of polycrystals becoming discontinuous rings, and in extreme cases, turning into diffraction spots like those of single crystals.", "choice_question": "When using X-ray detection, how does the diffraction of polycrystalline texture appear?", "conversion_reason": "The answer is a standard description of a phenomenon, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Discontinuous diffraction rings that may evolve into spot-like patterns", "B": "Perfectly continuous Debye-Scherrer rings with uniform intensity", "C": "Complete disappearance of diffraction patterns due to texture averaging", "D": "Multiple superimposed single-crystal spot patterns with random orientations" }, "correct_answer": "A", "explanation": "The correct answer A describes the actual diffraction behavior where preferred orientation causes discontinuous rings. Option B is a cognitive bias trap exploiting the common Debye-Scherrer ring misconception. Option C is a professional intuition trap suggesting texture would average out diffraction. Option D is a multi-layer verification trap combining single-crystal spots with texture in a misleading way.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3164, "question": "Calculate the number of vacancies n in 1 cm³ of copper at 1000°C, given the average vacancy concentration C≈6.27×10⁻⁵ and the number of atoms N≈0.84×10²³.", "answer": "n = N × C = 0.84×10²³ × 6.27×10⁻⁵ ≈ 5.27×10¹⁸", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算铜中空位数量），并给出了具体的公式和数值代入过程。答案是一个具体的计算结果，符合计算题的特征。 | 知识层次: 题目仅涉及基本公式的直接套用和简单计算，无需多步推理或综合分析 | 难度: 在选择题型中，该题目仅需要直接套用单一公式n = N × C进行计算，无需理解多个概念或进行复杂分析。解题步骤简单直接，属于最基础的难度等级。", "convertible": true, "correct_option": "5.27×10¹⁸", "choice_question": "Calculate the number of vacancies n in 1 cm³ of copper at 1000°C, given the average vacancy concentration C≈6.27×10⁻⁵ and the number of atoms N≈0.84×10²³.", "conversion_reason": "The calculation question has a definite numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.27×10¹⁸", "B": "6.27×10¹⁸", "C": "5.27×10²³", "D": "0.84×10²³" }, "correct_answer": "A", "explanation": "The correct answer is calculated by multiplying the vacancy concentration (C≈6.27×10⁻⁵) by the number of atoms (N≈0.84×10²³), resulting in n≈5.27×10¹⁸. Option B is a cognitive bias trap that directly uses the vacancy concentration value without proper calculation. Option C exploits unit confusion by incorrectly using the total number of atoms instead of vacancies. Option D is a professional intuition trap that presents the total number of atoms as if it were the vacancy count.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4541, "question": "Briefly explain the difference between oxidation and reduction electrochemical reactions.", "answer": "Oxidation is the process by which an atom gives up an electron (or electrons) to become a cation. Reduction is the process by which an atom acquires an extra electron (or electrons) and becomes an anion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要解释氧化和还原电化学反应的区别，答案以文字解释和论述的形式呈现，符合简答题的特征。 | 知识层次: 题目考查氧化和还原反应的基本定义和区别，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目要求考生解释氧化和还原电化学反应的基本区别，涉及两个相关概念的定义和对比。虽然需要理解并区分两个概念，但不需要复杂的分析或多步骤推理，属于概念解释和描述的难度层次。", "convertible": true, "correct_option": "Oxidation is the process by which an atom gives up an electron (or electrons) to become a cation. Reduction is the process by which an atom acquires an extra electron (or electrons) and becomes an anion.", "choice_question": "Which of the following correctly explains the difference between oxidation and reduction electrochemical reactions?", "conversion_reason": "The answer is a standard explanation of the concepts of oxidation and reduction, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Oxidation involves electron loss while reduction involves electron gain, with the oxidized species increasing its oxidation state", "B": "Oxidation is the formation of metal oxides while reduction is the decomposition of metal oxides", "C": "Oxidation occurs at the cathode while reduction occurs at the anode in electrochemical cells", "D": "Oxidation decreases atomic radius while reduction increases atomic radius, due to electron transfer" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely describes the fundamental electron transfer process in redox reactions. Option B is a common misconception confusing chemical reactions with electrochemical processes. Option C reverses the electrode processes, exploiting a frequent confusion in electrochemistry. Option D mixes valid atomic radius changes with incorrect causal relationships, creating a plausible-sounding but fundamentally flawed explanation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1825, "question": "One of the conditions for the peptization of clay slurry is (8)", "answer": "Polymerization of anions", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释粘土浆料胶溶的条件之一，答案需要提供文字解释而非选择或判断 | 知识层次: 题目考查对粘土浆体胶溶条件的基本概念记忆，只需要回忆和陈述\"阴离子聚合\"这一条件即可，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需回忆粘土浆体胶溶作用的条件之一即可。题目直接给出正确选项，无需复杂推理或概念比较，符合等级1的基本定义简答要求。", "convertible": true, "correct_option": "Polymerization of anions", "choice_question": "One of the conditions for the peptization of clay slurry is:", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polymerization of anions", "B": "Deprotonation of surface hydroxyl groups", "C": "Formation of hydrogen bonds between clay layers", "D": "Cation exchange capacity reduction" }, "correct_answer": "A", "explanation": "The correct answer is A because peptization requires the polymerization of anions to create repulsive forces between clay particles. Option B is a strong distractor as deprotonation is a common surface chemistry phenomenon but not the primary peptization mechanism. Option C exploits the intuitive but incorrect assumption about interlayer bonding. Option D uses a reverse logic trap by suggesting a reduction in cation exchange capacity, which is actually increased during peptization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2900, "question": "A ternary alloy with mass fractions of 40% A, 30% B, and 30% C forms a three-phase equilibrium at the eutectic temperature. The compositions of the three phases are as follows: liquid phase (50% A, 40% B, 10% C), α phase (85% A, 10% B, 5% C), and β phase (10% A, 20% B, 70% C). Calculate the fractions of the liquid phase, α phase, and β phase.", "answer": "First, draw a concentration triangle and mark the compositions of each phase. The alloy composition point is: L% = (57 - 30) / (57 - 10) × 100% = 57.4%; α% = (40 - 35) / (85 - 35) × 100% = 10%; β% = 100% - 57.4% - 10% = 32.6%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解各相的质量分数，答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要运用杠杆定律和相图知识进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解三元合金相图的基本概念，掌握杠杆定律在多组分系统中的应用，并进行多步骤计算。题目要求考生能够正确绘制浓度三角形并标记各相组成点，然后通过杠杆定律计算各相的质量分数。虽然题目提供了各相的组成，但计算过程涉及多个变量和步骤，需要较强的综合分析能力。", "convertible": true, "correct_option": "L% = 57.4%, α% = 10%, β% = 32.6%", "choice_question": "A ternary alloy with mass fractions of 40% A, 30% B, and 30% C forms a three-phase equilibrium at the eutectic temperature. The compositions of the three phases are as follows: liquid phase (50% A, 40% B, 10% C), α phase (85% A, 10% B, 5% C), and β phase (10% A, 20% B, 70% C). What are the fractions of the liquid phase, α phase, and β phase?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "L% = 57.4%, α% = 10%, β% = 32.6%", "B": "L% = 50%, α% = 25%, β% = 25%", "C": "L% = 40%, α% = 30%, β% = 30%", "D": "L% = 62.5%, α% = 12.5%, β% = 25%" }, "correct_answer": "A", "explanation": "正确答案A是通过杠杆法则和三元相图的质量平衡计算得出的精确解。干扰项B利用了对三元系统直觉性的对称分配错误；干扰项C直接采用了合金原始成分比例，忽略了相变后的成分重组；干扰项D则是在二元系统杠杆法则基础上进行了不恰当的三元系统扩展，这些都是先进AI系统在处理复杂相图计算时常见的错误类型。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3975, "question": "During the recovery of a cold-worked material, is all of the internal strain energy relieved?", "answer": "All of the internal strain energy is not relieved.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（\"is all of the internal strain energy relieved?\"），而答案直接给出了判断结果（\"All of the internal strain energy is not relieved.\"），这符合判断题的特征。 | 知识层次: 题目考查对冷加工材料恢复过程中内应变能释放情况的基本概念理解，属于基础知识的记忆和简单判断。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即冷加工材料恢复过程中内应变能是否完全释放的定义性知识。正确选项直接陈述了基本原理（内应变能不会完全释放），无需复杂理解或分析，属于基本概念正误判断的简单题目。", "convertible": true, "correct_option": "All of the internal strain energy is not relieved.", "choice_question": "During the recovery of a cold-worked material, is all of the internal strain energy relieved?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "During recrystallization of a cold-worked metal, the new grain structure forms only at locations with the highest dislocation density.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While recrystallization nuclei preferentially form in regions of high dislocation density, they can also form in other highly strained regions. The statement is overly absolute by using 'only', which makes it incorrect. Recrystallization depends on both stored strain energy and local boundary conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3088, "question": "What materials can be used to manufacture rocket supports? Options: A. Carbon fiber resin composite B. Thermosetting fiberglass C. Boron fiber resin composite", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案 | 知识层次: 题目考查对火箭支撑材料的基本概念记忆，只需要从给定的选项中选择正确的材料类型，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，此题需要考生理解不同复合材料的基本特性及其在火箭支撑结构中的应用。虽然选项都是复合材料，但需要考生对硼纤维树脂复合材料的特殊性能（如高强度、高刚度）有一定了解才能正确选择。这超出了简单的概念识别（等级1），但尚未达到需要复杂概念区分（等级3）的程度。", "convertible": true, "correct_option": "C. Boron fiber resin composite", "choice_question": "What materials can be used to manufacture rocket supports?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Carbon fiber reinforced polymer with 0° ply orientation", "B": "Silicon carbide fiber reinforced titanium matrix composite", "C": "Boron fiber reinforced epoxy with 45° ply orientation", "D": "Unidirectional alumina fiber reinforced aluminum matrix composite" }, "correct_answer": "C", "explanation": "The correct answer is C because boron fiber composites provide the optimal combination of high specific stiffness (critical for minimizing weight) and thermal stability required for rocket supports. The 45° ply orientation provides balanced shear resistance during launch vibrations. Option A is a cognitive bias trap - while CFRP has excellent stiffness, the 0° orientation lacks necessary shear resistance. Option B is a professional intuition trap - while SiC/Ti has good high-temperature properties, its CTE mismatch causes delamination under thermal cycling. Option D is a multi-level verification trap - alumina/Al has good stiffness but poor fatigue resistance under cyclic loading.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 828, "question": "Indicate the second main mechanism of alloy strengthening and explain its strengthening reason", "answer": "Precipitation strengthening and dispersion strengthening. The compounds of alloying elements and matrix elements obtained through phase transformation processes in alloys, as well as hard particles mechanically mixed into the matrix material, both cause alloy strengthening, referred to as precipitation strengthening and dispersion strengthening, respectively. The effects of precipitation strengthening and dispersion strengthening are much greater than solid solution strengthening. When dislocations encounter second phases during movement, they need to cut through (small-sized particles in precipitation strengthening and particles in dispersion strengthening) or bypass (large-sized particles in precipitation strengthening) the second phases. Therefore, the second phases (precipitates and dispersoids) hinder dislocation motion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释合金强化的第二种主要机制及其强化原因，需要详细的文字解释和论述，而不是简单的选择、判断或计算。答案也提供了详细的解释和论述，符合简答题的特征。 | 知识层次: 题目不仅要求记忆合金强化的第二种主要机制（沉淀强化和弥散强化），还需要解释其强化原因，涉及位错运动与第二相粒子的相互作用机制。这需要理解概念之间的关联，并进行一定的综合分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。题目不仅要求识别合金强化的第二种主要机制（沉淀强化和弥散强化），还需要理解其强化原理。正确选项涉及多个概念的综合分析，包括相变过程、第二相粒子对位错运动的阻碍机制（切割或绕过），以及与固溶强化的效果比较。这需要考生具备较深的知识掌握和多角度分析能力，超出了简单的记忆或单一概念的应用。", "convertible": true, "correct_option": "Precipitation strengthening and dispersion strengthening", "choice_question": "Which of the following is the second main mechanism of alloy strengthening?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by asking for the correct mechanism from a list of options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Precipitation strengthening and dispersion strengthening", "B": "Grain boundary strengthening through Hall-Petch effect", "C": "Solid solution strengthening by interstitial atoms", "D": "Work hardening through dislocation accumulation" }, "correct_answer": "A", "explanation": "Precipitation strengthening and dispersion strengthening are the second main mechanisms after solid solution strengthening. Option B exploits the common misconception that grain refinement is always the primary strengthening method. Option C is a trap for those who confuse the first mechanism (solid solution) with the second. Option D targets the intuitive but incorrect association between visible deformation and strengthening hierarchy.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 43, "question": "According to the radius ratio relationship, what is the coordination number when Al3+ coordinates with O2-? Given rO2-=0.132nm, rAl3+=0.057nm.", "answer": "For Al3+, r+/r-=0.057/0.132=0.43; based on the relationship between cation coordination number and the radius ratio of positive to negative ions, the coordination number is 6.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的离子半径进行数值计算（r+/r-比值），并根据半径比关系确定配位数。解答过程涉及具体计算步骤和公式应用，符合计算题的特征。 | 知识层次: 题目主要涉及半径比的计算和基本配位数关系的直接应用，属于基本公式套用和简单计算范畴，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目仅需应用半径比公式（r+/r-）进行简单计算，并根据给定的半径比直接查表或记忆对应的配位数。无需多个公式组合或复杂推理，解题步骤简单直接，属于基础知识的简单应用。", "convertible": true, "correct_option": "6", "choice_question": "According to the radius ratio relationship, what is the coordination number when Al3+ coordinates with O2-? Given rO2-=0.132nm, rAl3+=0.057nm.", "conversion_reason": "The calculation question has a definite numerical answer, which can be converted into a multiple-choice question format with the correct option being the calculated coordination number.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "选项B", "C": "选项D", "D": "6" }, "correct_answer": "D", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 4004, "question": "Does decreasing specimen thickness favor brittle fracture in polymers?", "answer": "No, decreasing specimen thickness does not favor brittle fracture in polymers.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（\"Does decreasing specimen thickness favor brittle fracture in polymers?\"），而答案直接给出了对错判断（\"No\"），符合判断题的特征。 | 知识层次: 题目考查对聚合物断裂行为的基本概念的理解，属于基础概念记忆范畴，不需要复杂的分析或计算。 | 难度: 该题目属于基础概念记忆层次，仅需判断\"减小试样厚度是否有利于聚合物脆性断裂\"这一基本概念的正误。正确选项直接给出了明确的否定结论，不需要任何概念理解或分析过程，属于选择题型中最简单的正误判断题。", "convertible": true, "correct_option": "No, decreasing specimen thickness does not favor brittle fracture in polymers.", "choice_question": "Does decreasing specimen thickness favor brittle fracture in polymers?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "For all polymers, decreasing specimen thickness always favors brittle fracture.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While thinner specimens generally show more ductile behavior in polymers due to constrained plastic deformation, this is not universally true for all polymers. Some semi-crystalline polymers may exhibit increased brittleness at very small thicknesses due to molecular alignment effects. The use of 'all' and 'always' makes this statement incorrect, as material behavior depends on polymer type, testing conditions, and specific thickness ranges.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2232, "question": "Determine whether the following statement is correct. (2) Dynamic recrystallization only occurs under hot deformation conditions, therefore, metals deformed at room temperature will not undergo dynamic recrystallization.", "answer": "Incorrect. The recrystallization temperature of some metals is below room temperature, so deformation at room temperature is also considered hot deformation, and dynamic recrystallization can occur.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断陈述的正确性，答案明确指出了原陈述的错误并给出了解释，符合判断题的特征。 | 知识层次: 题目不仅需要理解动态再结晶的基本概念，还需要结合不同金属的再结晶温度进行综合分析，判断在室温条件下是否可能发生动态再结晶。这涉及到对概念的应用和一定程度的推理分析。 | 难度: 在选择题中属于较高难度，需要综合分析动态再结晶的条件和金属的再结晶温度概念，并理解室温变形对某些金属而言可能属于热变形范畴。题目要求考生不仅掌握基础概念，还需要进行多步逻辑推理和特殊情况判断。", "convertible": true, "correct_option": "Incorrect. The recrystallization temperature of some metals is below room temperature, so deformation at room temperature is also considered hot deformation, and dynamic recrystallization can occur.", "choice_question": "Determine whether the following statement is correct. (2) Dynamic recrystallization only occurs under hot deformation conditions, therefore, metals deformed at room temperature will not undergo dynamic recrystallization.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "Dynamic recrystallization only occurs under hot deformation conditions, therefore, metals deformed at room temperature will not undergo dynamic recrystallization.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "The statement is incorrect because the recrystallization temperature of some metals is below room temperature. For these metals, deformation at room temperature is considered hot deformation, and dynamic recrystallization can occur. The original statement makes an absolute claim that ignores this important exception in material behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 136, "question": "The viscosity of SiO2 melt is 10^14 Pa·s at 1000°C and 10^7 Pa·s at 1400°C. What is the activation energy for viscous flow of SiO2 glass?", "answer": "According to the formula: η=η0exp(ΔE/RT)\\nAt 1000°C, η=10^14 Pa·s, T=1000+273=1273 K\\nAt 1400°C, η=10^7 Pa·s, T=1400+273=1673 K\\nSolving the two equations simultaneously yields: η0=5.27×10^-16 Pa·s\\nΔE=713.5 kJ/mol", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解SiO2玻璃的粘流活化能，答案中包含了具体的计算步骤和结果。 | 知识层次: 题目需要应用Arrhenius方程进行多步计算，涉及温度转换和联立方程求解，属于中等应用层次。虽然不涉及复杂的概念关联或综合分析，但需要一定的计算能力和公式应用技巧。 | 难度: 在选择题中属于中等难度，需要理解粘度与温度的关系公式，进行多步计算（包括温度转换和联立方程求解），并综合分析结果。虽然题目提供了公式和步骤，但计算过程较为复杂，涉及对数运算和单位转换，对学生的计算能力和概念理解有一定要求。", "convertible": true, "correct_option": "713.5 kJ/mol", "choice_question": "The viscosity of SiO2 melt is 10^14 Pa·s at 1000°C and 10^7 Pa·s at 1400°C. What is the activation energy for viscous flow of SiO2 glass?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "713.5 kJ/mol", "B": "485.2 kJ/mol", "C": "327.8 kJ/mol", "D": "1024.6 kJ/mol" }, "correct_answer": "A", "explanation": "正确答案A是通过Arrhenius方程计算得到的精确值。干扰项B利用了温度对数坐标下的斜率误判，是常见计算错误。干扰项C对应的是晶体SiO2的激活能，利用了材料相态混淆。干扰项D故意放大了温度系数的影响，利用了数量级直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3774, "question": "Does the cast iron expand or contract during solidification?", "answer": "the cast iron contracts during solidification.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（cast iron在凝固过程中是膨胀还是收缩），答案直接给出了对错判断（contracts during solidification） | 知识层次: 题目考查对铸铁凝固过程中体积变化这一基本概念的记忆和理解，属于基础概念记忆范畴。 | 难度: 该题目属于基础概念记忆层次，仅需判断铸铁在凝固过程中是膨胀还是收缩这一简单事实。在选择题型中，这属于最基本的概念正误判断，不需要复杂的理解或分析过程，因此属于等级1难度。", "convertible": true, "correct_option": "the cast iron contracts during solidification.", "choice_question": "Does the cast iron expand or contract during solidification?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All types of cast iron contract during solidification without exception.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most cast irons contract during solidification due to the density increase from liquid to solid, certain alloyed cast irons with high graphite content can exhibit expansion due to graphite precipitation. The absolute term 'all' makes this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2535, "question": "Briefly describe the influence of atomic radius difference on solid solubility according to the Hume-Rothery rules", "answer": "If the difference in atomic radii of the elements forming the alloy exceeds 14%~15%, the solid solubility is extremely limited.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述原子半径差异对固溶度的影响，需要文字解释和论述，而不是选择、判断或计算。答案也是以文字形式给出的解释性陈述。 | 知识层次: 题目考查Hume-Rothery规则中原子半径差异对固溶度影响的基本概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（Hume-Rothery规则），但需要考生不仅记住原子半径差异的百分比限制（14%~15%），还要理解这一数值对固溶度的具体影响（\"extremely limited\"）。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述或比较分析（等级3）。题目正确选项完整呈现了概念解释和描述层面的知识，符合等级2的难度特征。", "convertible": true, "correct_option": "If the difference in atomic radii of the elements forming the alloy exceeds 14%~15%, the solid solubility is extremely limited.", "choice_question": "According to the Hume-Rothery rules, which of the following statements correctly describes the influence of atomic radius difference on solid solubility?", "conversion_reason": "The answer is a standard concept that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "If the difference in atomic radii of the elements forming the alloy exceeds 14%~15%, the solid solubility is extremely limited.", "B": "A 5%~7% atomic radius difference maximizes solid solubility by creating optimal lattice strain for defect stabilization.", "C": "Atomic radius difference has negligible effect on solid solubility compared to electronegativity differences.", "D": "Solid solubility increases proportionally with atomic radius difference up to 20% due to enhanced entropy of mixing." }, "correct_answer": "A", "explanation": "Correct answer A follows the classic Hume-Rothery rule where exceeding 14-15% radius difference severely limits solubility due to excessive lattice strain. Option B is a cognitive bias trap, combining correct percentage range with wrong mechanistic explanation (strain stabilization instead of solubility limitation). Option C exploits electronegativity's actual importance but falsely negates radius effects. Option D creates a multi-layer trap by combining real entropy concepts with incorrect proportional relationship beyond the critical radius difference threshold.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1808, "question": "Kaolinite belongs to the layered silicate structure, and its structural feature is a. two-layer type trioctahedral structure b. three-layer type trioctahedral structure c. two-layer type dioctahedral structure d. three-layer type dioctahedral structure", "answer": "c", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从四个选项中选择关于高岭石结构特征的正确答案 | 知识层次: 题目考查对高岭石（Kaolinite）结构特征的基础概念记忆，属于对层状硅酸盐结构分类的基本知识点的直接考察。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆，但需要考生对高岭石的结构特征有清晰的理解，并能够区分两层型和三层型、三八面体和二八面体等专业术语。题目要求考生不仅记住高岭石属于二八面体结构，还要在四个相似选项中准确识别出正确描述。这比单纯的概念识别（等级1）要求更高，但尚未达到需要深度理解和复杂概念区分的等级3难度。", "convertible": true, "correct_option": "c. two-layer type dioctahedral structure", "choice_question": "Kaolinite belongs to the layered silicate structure, and its structural feature is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship predicts increased ductility with decreasing grain size due to enhanced dislocation mobility", "B": "The Hall-Petch relationship shows a linear increase in yield strength with the inverse square root of grain size, valid down to the nanoscale", "C": "The Hall-Petch relationship describes a logarithmic dependence of hardness on grain boundary density", "D": "The Hall-Petch relationship becomes invalid below 100nm grain size due to dislocation starvation effects" }, "correct_answer": "D", "explanation": "The correct answer is D because the Hall-Petch relationship breaks down at nanoscale grain sizes (<100nm) due to dislocation starvation and grain boundary-mediated deformation mechanisms. Option A is incorrect as it reverses the actual effect (strength increases, ductility decreases with finer grains). Option B is a classic trap as it states the correct mathematical form but falsely claims validity at nanoscale. Option C uses a plausible-sounding but fundamentally wrong mathematical relationship.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4250, "question": "The diffusion coefficients for iron in nickel are given at two temperatures: 1273 K with D = 9.4 x 10^-16 m^2/s and 1473 K with D = 2.4 x 10^-14 m^2/s. Determine the values of D0 and the activation energy Qd.", "answer": "the values are d0 = 2.2 x 10^-5 m^2/s and the activation energy qd = 252,400 j/mol.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的扩散系数和温度数据，使用阿伦尼乌斯方程计算D0和激活能Qd的数值。解答过程涉及数值计算和公式应用，答案也是具体的数值结果。 | 知识层次: 题目需要应用扩散系数的阿伦尼乌斯方程进行多步计算，涉及对数运算和联立方程求解，需要理解温度与扩散系数的关系并正确应用公式，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散系数与温度的关系（阿伦尼乌斯方程），并能够进行多步骤的计算来求解D0和激活能Qd。虽然题目提供了正确选项，但解题过程涉及对数运算和联立方程求解，对学生的计算能力和概念理解有较高要求。", "convertible": true, "correct_option": "D0 = 2.2 x 10^-5 m^2/s and Qd = 252,400 J/mol", "choice_question": "Given the diffusion coefficients for iron in nickel at two temperatures (1273 K with D = 9.4 x 10^-16 m^2/s and 1473 K with D = 2.4 x 10^-14 m^2/s), determine the values of D0 and the activation energy Qd.", "conversion_reason": "The calculation question has a specific and deterministic answer, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "D0 = 2.2 x 10^-5 m^2/s and Qd = 252,400 J/mol", "B": "D0 = 1.1 x 10^-5 m^2/s and Qd = 126,200 J/mol", "C": "D0 = 4.4 x 10^-5 m^2/s and Qd = 252,400 J/mol", "D": "D0 = 2.2 x 10^-5 m^2/s and Qd = 126,200 J/mol" }, "correct_answer": "A", "explanation": "The correct answer A is derived from solving the Arrhenius equation system for both temperatures. Option B halves both values, exploiting the AI's potential to miscalculate logarithmic relationships. Option C doubles D0 while keeping Qd correct, targeting errors in pre-exponential factor determination. Option D keeps D0 correct but halves Qd, exploiting confusion between activation energy and its temperature dependence.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4880, "question": "What is the process of transfer molding used to form plastic materials?", "answer": "For transfer molding, the solid materials (normally thermosetting in nature) are first melted in the transfer chamber prior to being forced into the die.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释transfer molding的过程，答案提供了详细的文字描述和论述，符合简答题的特征 | 知识层次: 题目考查对转移模塑工艺的基本概念和过程的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（定义、分类、基本原理等），但需要考生理解并描述转移模塑的具体过程，包括材料的初始状态（固体热固性材料）、熔化过程（在转移室中）以及最终成型方式（被压入模具）。这比简单的定义记忆（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "For transfer molding, the solid materials (normally thermosetting in nature) are first melted in the transfer chamber prior to being forced into the die.", "choice_question": "What is the process of transfer molding used to form plastic materials?", "conversion_reason": "The answer is a standard description of the process, which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The material is first melted in a transfer chamber before being forced into the die", "B": "The material is directly injected into the mold in its solid state", "C": "The process involves simultaneous melting and shaping within the mold cavity", "D": "A pre-heated thermoplastic sheet is forced into the mold under vacuum" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the two-stage process of transfer molding where thermosetting materials are first melted in a separate chamber. Option B is incorrect because it confuses transfer molding with compression molding. Option C creates confusion by blending injection molding characteristics. Option D introduces a thermoplastic processing method (thermoforming) that's irrelevant to transfer molding's thermosetting nature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1536, "question": "Crystal", "answer": "Crystal: A solid composed of atoms, molecules, or ions arranged in a regular periodic pattern", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Crystal\"进行定义和解释，需要文字描述和论述，属于简答题类型 | 知识层次: 题目考查对晶体这一基本概念的定义和记忆，属于基础概念的记忆性知识，不涉及应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别晶体的基本定义，属于最基础的概念记忆层次。题目仅涉及单一知识点的直接回忆，无需解释或分析，解题步骤极为简单，符合等级1“基本定义简答”的标准。", "convertible": true, "correct_option": "A solid composed of atoms, molecules, or ions arranged in a regular periodic pattern", "choice_question": "下列关于Crystal的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A solid composed of atoms, molecules, or ions arranged in a regular periodic pattern", "B": "Any solid material with long-range atomic ordering, including amorphous solids", "C": "A material exhibiting both crystalline and amorphous regions simultaneously", "D": "A solid phase that necessarily exhibits anisotropic physical properties" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a crystal as having a regular periodic arrangement of constituent particles. Option B is incorrect because it falsely includes amorphous solids which lack long-range order - this exploits the common confusion between short-range and long-range order. Option C describes a semi-crystalline material but incorrectly presents it as the definition of a crystal - this traps those who conflate specialized cases with fundamental definitions. Option D introduces an unnecessary constraint (anisotropy) which while common is not definitional - this exploits the tendency to overgeneralize from typical examples.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 525, "question": "What changes occur in the properties of metal after plastic deformation?", "answer": "In terms of properties, cold-deformed metal will undergo work hardening, manifested as a significant increase in strength and a noticeable decrease in plasticity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释金属在塑性变形后性质的变化，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查金属塑性变形后性能变化的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并描述金属塑性变形后的具体性能变化（如加工硬化、强度增加和塑性下降），而不仅仅是简单的定义或分类。这要求考生对相关概念有一定的理解和应用能力，但不需要进行复杂的体系阐述或比较分析。", "convertible": true, "correct_option": "In terms of properties, cold-deformed metal will undergo work hardening, manifested as a significant increase in strength and a noticeable decrease in plasticity.", "choice_question": "What changes occur in the properties of metal after plastic deformation?", "conversion_reason": "The answer is a standard description of the changes in metal properties after plastic deformation, which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yield strength increases while ductility decreases due to dislocation entanglement", "B": "Elastic modulus significantly increases as atomic bonds strengthen", "C": "Electrical conductivity improves due to grain boundary reduction", "D": "Thermal expansion coefficient decreases as crystal structure becomes more ordered" }, "correct_answer": "A", "explanation": "Correct answer A describes the well-documented work hardening phenomenon where dislocation entanglement increases yield strength at the expense of ductility. Option B is a cognitive bias trap - elastic modulus is an intrinsic property largely unaffected by plastic deformation. Option C exploits common misconceptions about conductivity - while grain boundaries decrease, dislocation density increases, actually reducing conductivity. Option D is a multi-level trap combining incorrect assumptions about thermal expansion and crystal ordering during plastic deformation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3986, "question": "Grain growth requirements\n}\nGrain growth must always be preceded by recovery and recrystallization.(a) True(b) False", "answer": "False. Grain growth does not always need to be preceded by recovery and recrystallization; it may occur in materials that have not been cold worked.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（True or False），答案直接给出了False的判断并提供了简要解释，符合判断题的特征。 | 知识层次: 题目考查对晶粒生长基本概念的理解，需要记忆和判断晶粒生长是否必须经过回复和再结晶过程，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆和理解晶粒生长的基本条件即可作答，无需复杂分析或比较多个概念。", "convertible": true, "correct_option": "False. Grain growth does not always need to be preceded by recovery and recrystallization; it may occur in materials that have not been cold worked.", "choice_question": "Grain growth requirements\n}\nGrain growth must always be preceded by recovery and recrystallization.(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In nanocrystalline materials, grain growth always leads to a decrease in hardness according to the Hall-Petch relationship.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the Hall-Petch relationship generally predicts increased hardness with decreasing grain size, nanocrystalline materials may exhibit inverse Hall-Petch behavior at extremely small grain sizes (<10nm) where grain boundary sliding becomes dominant. Additionally, some nanocrystalline materials may maintain high hardness even after grain growth due to unique grain boundary structures or second phase pinning effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4242, "question": "(a) Briefly describe a twin and a twin boundary.", "answer": "A twin boundary is an interface such that atoms on one side are located at mirror image positions of those atoms situated on the other boundary side. The region on one side of this boundary is called a twin.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述孪晶和孪晶界，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对孪晶和孪晶界面的基本定义和概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅要求考生记忆并复述孪晶和孪晶界面的基本定义，属于最基础的概念记忆层次。题目仅涉及单一概念的定义性描述，无需进行解释或比较分析，解题步骤简单直接，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "A twin boundary is an interface such that atoms on one side are located at mirror image positions of those atoms situated on the other boundary side. The region on one side of this boundary is called a twin.", "choice_question": "下列关于孪晶和孪晶界的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A twin boundary is an interface such that atoms on one side are located at mirror image positions of those atoms situated on the other boundary side. The region on one side of this boundary is called a twin.", "B": "A twin boundary is a high-angle grain boundary with misorientation angle greater than 15 degrees, where the atomic arrangement is completely random across the boundary.", "C": "A twin boundary is a special type of stacking fault where the crystal structure changes abruptly without any mirror symmetry, commonly observed in FCC metals under high stress.", "D": "A twin boundary is a phase boundary separating two distinct crystal structures, where the lattice parameters on either side are fundamentally different." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines twin boundaries as mirror-symmetric interfaces and twins as the mirrored regions. Option B incorrectly describes twins as high-angle grain boundaries. Option C falsely equates twins with stacking faults. Option D erroneously presents twins as phase boundaries between different crystal structures. These distractors exploit common misconceptions about grain boundaries, stacking faults, and phase boundaries in material science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 966, "question": "Briefly describe secondary recrystallization", "answer": "The phenomenon of abnormal growth of a few grains that occurs when the normal growth process is inhibited after recrystallization is completed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述二次再结晶现象，需要用文字进行解释和论述，符合简答题的特征 | 知识层次: 题目考查对二次再结晶这一基本概念的定义和现象描述，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。虽然题目要求描述二次再结晶现象，但正确选项已经提供了明确的定义和关键特征（异常晶粒生长、正常生长过程被抑制等），不需要考生进行复杂的分析或比较。这属于对基础概念的理解和记忆，但比简单定义类题目（等级1）需要稍多的知识掌握深度。", "convertible": true, "correct_option": "The phenomenon of abnormal growth of a few grains that occurs when the normal growth process is inhibited after recrystallization is completed.", "choice_question": "Which of the following best describes secondary recrystallization?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phenomenon of abnormal growth of a few grains that occurs when the normal growth process is inhibited after recrystallization is completed", "B": "A second stage of recrystallization where all grains grow uniformly due to stored energy release", "C": "The process where previously recrystallized grains undergo phase transformation under thermal treatment", "D": "The selective dissolution of small grains leading to coarsening of the microstructure" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines secondary recrystallization as the abnormal growth of a few grains when normal grain growth is inhibited. Option B is designed to exploit the common intuition that 'secondary' implies a uniform second stage process. Option C creates confusion with phase transformation phenomena that may occur during heat treatment. Option D mimics aspects of Ostwald ripening to trap those who confuse coarsening mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2283, "question": "Calculate the fiber stress σf of Al2O3 short fibers when the length exceeds the critical length, given the fiber tensile strength σfa=2275MPa, critical length Lc=299.3μm, and actual length L=4mm.", "answer": "For Al2O3 short fibers, the fiber stress σf = (1 - Lc/(2L)) × σfa = (1 - 299.3×10^-6/(2 × 4000×10^-6)) × 2275 = 2190MPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及具体的数学运算和单位转换，最终给出一个具体的数值结果。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，虽然需要理解临界长度的概念，但整体思维过程较为直接，属于基本公式套用和数值计算的范畴。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解临界长度和实际长度的概念，但解题步骤仅涉及直接套用一个明确的公式（σf = (1 - Lc/(2L)) × σfa），并进行简单的单位换算和代数运算。不需要多个公式组合或复杂的推导过程，因此难度等级为2。", "convertible": true, "correct_option": "2190MPa", "choice_question": "Calculate the fiber stress σf of Al2O3 short fibers when the length exceeds the critical length, given the fiber tensile strength σfa=2275MPa, critical length Lc=299.3μm, and actual length L=4mm.", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2190MPa", "B": "2275MPa", "C": "2045MPa", "D": "2350MPa" }, "correct_answer": "A", "explanation": "The correct answer is A (2190MPa) because when the fiber length exceeds the critical length, the fiber stress is calculated using the formula σf = σfa * (1 - Lc/(2L)), where σfa is the fiber tensile strength (2275MPa), Lc is the critical length (299.3μm), and L is the actual length (4mm). Plugging in the values gives σf = 2275 * (1 - 299.3/(2*4000)) ≈ 2190MPa. Option B (2275MPa) is a trap for those who mistakenly assume full strength is achieved immediately after exceeding critical length. Option C (2045MPa) incorrectly uses Lc/L instead of Lc/(2L). Option D (2350MPa) is a distraction based on common alumina composite strength values but irrelevant here.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 793, "question": "Explain what type of solid solution compound Fe3C belongs to", "answer": "Fe3C is an interstitial compound, belonging to the interstitial phase with a complex structure", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释Fe3C属于哪种固溶体化合物，需要文字解释和论述，答案也是以文字形式给出解释说明 | 知识层次: 题目考查对Fe3C分类的基础概念记忆和理解，属于材料科学中固溶体类型的基本知识点，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确理解并区分不同类型的固溶体化合物（如间隙相和间隙化合物），并能够正确识别Fe3C的具体分类。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的体系阐述（等级3）。", "convertible": true, "correct_option": "Fe3C is an interstitial compound, belonging to the interstitial phase with a complex structure", "choice_question": "What type of solid solution compound does Fe3C belong to?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial compound with complex structure", "B": "Substitutional solid solution with FCC lattice", "C": "Intermetallic compound with L12 ordered structure", "D": "Interstitial solid solution with BCC lattice" }, "correct_answer": "A", "explanation": "Fe3C (cementite) is a classic interstitial compound where small carbon atoms occupy interstitial sites in the iron lattice, forming a complex orthorhombic structure. Option B is incorrect because it describes a substitutional solid solution (like austenite) rather than an interstitial compound. Option C uses a real ordered structure (L12) but applies it incorrectly to an interstitial system. Option D mimics the correct 'interstitial' concept but wrongly assigns it to a simple BCC solid solution (like ferrite) rather than the complex compound structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 912, "question": "What is the difference in orientation relationship between growth during recrystallization and growth during solidification?", "answer": "During solidification growth, there is no orientation relationship with the parent phase, whereas during recrystallization growth, a specific orientation relationship may exist.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释两种生长过程中的取向关系差异，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求比较两种不同生长过程中的取向关系，涉及对再结晶和凝固过程的理解，需要将多个概念关联起来进行综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及再结晶和凝固过程中的取向关系差异，要求考生掌握两种不同相变过程的基本原理，并能区分它们之间的关键区别。虽然不需要复杂的计算，但需要对材料科学中的相变和晶体生长有较深入的理解。", "convertible": true, "correct_option": "During solidification growth, there is no orientation relationship with the parent phase, whereas during recrystallization growth, a specific orientation relationship may exist.", "choice_question": "What is the difference in orientation relationship between growth during recrystallization and growth during solidification?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization growth maintains a strict Burgers orientation relationship, while solidification growth has random orientation", "B": "Both processes maintain Kurdjumov-Sachs orientation relationships with their parent phases", "C": "Solidification growth follows a specific orientation relationship due to dendritic growth patterns, while recrystallization is random", "D": "Recrystallization shows no orientation relationship due to strain-induced boundary migration, while solidification maintains cube-on-cube orientation" }, "correct_answer": "A", "explanation": "The correct answer is A because recrystallization often maintains specific orientation relationships (like Burgers) with the deformed matrix, while solidification growth from liquid has no crystalline parent phase to maintain orientation with. Option B is wrong because K-S relationships apply to phase transformations, not solidification. Option C reverses the actual behavior - dendritic growth doesn't imply orientation relationships. Option D incorrectly states recrystallization has no orientation relationship, when in fact strain-induced boundaries often maintain specific misorientations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2277, "question": "From the perspective of wettability, should β-SiC whiskers or Al2O3 short fibers be selected as the reinforcement for aluminum matrix composites? It is known that the wettability of molten aluminum on β-SiC is higher than that on Al2O3.", "answer": "The wettability of molten aluminum on β-SiC is higher than that on Al2O3. From the perspective of wettability, β-SiC whiskers should be selected as the reinforcement.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求从润湿性角度分析并选择增强材料，答案需要文字解释和论述，而非简单的选择或判断。 | 知识层次: 题目要求从润湿性角度分析并选择增强材料，涉及对润湿性概念的理解和应用，需要综合分析已知条件（熔融铝在β-SiC上的润湿性高于Al2O3）并做出合理选择。虽然不涉及复杂计算，但需要关联概念和进行简单推理。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生从润湿性的角度选择增强材料，需要掌握润湿性的概念及其对复合材料性能的影响，并比较两种材料（β-SiC晶须和Al2O3短纤维）在润湿性上的差异。虽然题目提供了关键信息（熔融铝在β-SiC上的润湿性高于Al2O3），但仍需要考生进行综合分析才能得出正确结论。", "convertible": true, "correct_option": "β-SiC whiskers should be selected as the reinforcement.", "choice_question": "From the perspective of wettability, which reinforcement should be selected for aluminum matrix composites, given that the wettability of molten aluminum on β-SiC is higher than that on Al2O3?", "conversion_reason": "The answer is a standard choice between two options, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "β-SiC whiskers due to superior wettability", "B": "Al2O3 short fibers for better thermal stability", "C": "Equal preference as wettability difference is negligible", "D": "Neither, as both require expensive surface treatments" }, "correct_answer": "A", "explanation": "The correct answer is A because higher wettability directly improves interfacial bonding in composites. Option B exploits thermal stability bias despite being irrelevant to wettability. Option C creates a false equivalence trap by downplaying the significant wettability difference. Option D introduces an economic distraction unrelated to the wettability criterion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 97, "question": "In the non-stoichiometric compound Fe_xO, Fe^{3+}/Fe^{2+}=0.1, find the value of x in Fe_xO.", "answer": "Let y be the concentration of Fe^{3+}, y=0.0435. x=1-y=1-0.0435=0.9565, thus the chemical formula is Fe_0.9565O.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解非化学计量化合物Fe_xO中的x值，答案是一个具体的数值结果，解答过程涉及化学计量和电荷平衡的计算。 | 知识层次: 题目涉及非化学计量化合物的计算，需要理解Fe^{3+}/Fe^{2+}比例的概念，并进行多步计算来确定x的值。虽然计算过程不算特别复杂，但需要将概念与计算结合起来，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解非化学计量比化合物的概念，掌握Fe^{3+}/Fe^{2+}比例的计算方法，并进行多步计算才能得出最终结果。虽然题目提供了部分计算过程，但仍需要考生具备综合分析能力和化学计量关系的理解。", "convertible": true, "correct_option": "0.9565", "choice_question": "In the non-stoichiometric compound Fe_xO, Fe^{3+}/Fe^{2+}=0.1, what is the value of x in Fe_xO?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.9565", "B": "0.9478", "C": "0.9652", "D": "0.9357" }, "correct_answer": "A", "explanation": "The correct answer is A (0.9565) because it accounts for the exact charge balance considering the Fe³⁺/Fe²⁺ ratio of 0.1. Option B (0.9478) is a common error when neglecting the oxygen vacancy contribution. Option C (0.9652) results from incorrectly assuming all iron is Fe²⁺. Option D (0.9357) arises from overestimating the Fe³⁺ concentration. Advanced AIs may fail by either oversimplifying the charge balance or misapplying defect chemistry principles.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4719, "question": "Some hypothetical alloy is composed of 25 wt% of metal A and 75 wt% of metal B. If the densities of metals A and B are 6.17 and 8.00g / {cm}^{3}, respectively, and their respective atomic weights are 171.3 and 162.0g / mol, determine whether the crystal structure for this alloy is simple cubic, face-centered cubic, or body-centered cubic. Assume a unit cell edge length of 0.332nm.", "answer": "the crystal structure is simple cubic with 1.00 atom per unit cell.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行一系列数值计算，包括重量百分比、密度、原子重量和单位晶胞边长等，以确定晶体结构类型。答案基于计算结果得出，而非从给定选项中选择或简单判断对错。 | 知识层次: 题目需要进行多步计算，包括质量分数到原子分数的转换、密度计算、单位晶胞原子数的确定等，涉及多个概念的综合应用和关联分析，但不需要复杂的推理或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要综合运用多个概念并进行多步计算。题目涉及合金成分、密度、原子量以及晶体结构的综合分析，解题步骤包括计算合金密度、确定单位晶胞中的原子数等，需要较强的概念关联和计算能力。", "convertible": true, "correct_option": "simple cubic", "choice_question": "Some hypothetical alloy is composed of 25 wt% of metal A and 75 wt% of metal B. If the densities of metals A and B are 6.17 and 8.00g / {cm}^{3}, respectively, and their respective atomic weights are 171.3 and 162.0g / mol, and a unit cell edge length of 0.332nm is assumed, the crystal structure for this alloy is:", "conversion_reason": "The original question is a calculation problem with a definitive answer that can be presented as a choice among given options (simple cubic, face-centered cubic, body-centered cubic). The answer provided is specific and matches one of the potential options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "simple cubic", "B": "face-centered cubic", "C": "body-centered cubic", "D": "hexagonal close-packed" }, "correct_answer": "A", "explanation": "The correct answer is simple cubic because the calculated number of atoms per unit cell (1.0) matches this structure. Option B (FCC) is a common mistake due to its prevalence in real alloys, but would require 4 atoms per unit cell. Option C (BCC) is a plausible distractor as it's the second most common structure, but requires 2 atoms per unit cell. Option D (HCP) exploits the tendency to assume close-packed structures for alloys, though the calculation clearly shows a simple cubic arrangement.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4666, "question": "Cobalt (Co) has an HCP crystal structure, an atomic radius of 0.1253nm, and a c/a ratio of 1.623. Compute the volume of the unit cell for Co.", "answer": "the volume of the unit cell for co is 6.64 × 10^{-23} {cm}^3 or 6.64 × 10^{-2} nm^3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解钴的单位晶胞体积，答案给出了具体的数值结果，符合计算题的特征。 | 知识层次: 题目要求计算HCP晶胞体积，涉及基本公式应用和简单计算，属于直接套用公式的简单应用层次。虽然需要理解HCP结构和相关参数，但不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用HCP晶体结构的体积计算公式，但题目已经提供了所有必要的参数（原子半径和c/a比），计算过程直接且无需复杂推导。学生只需正确代入公式并完成单位转换即可得到答案，属于基础层次的应用题。", "convertible": true, "correct_option": "6.64 × 10^{-23} cm^3", "choice_question": "Cobalt (Co) has an HCP crystal structure, an atomic radius of 0.1253nm, and a c/a ratio of 1.623. What is the volume of the unit cell for Co?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.64 × 10^{-23} cm^3", "B": "3.32 × 10^{-23} cm^3", "C": "9.96 × 10^{-23} cm^3", "D": "1.33 × 10^{-22} cm^3" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the HCP unit cell volume formula V = (3√3/2)a²c, where a = 2r and c/a = 1.623. Option B is half the correct volume, exploiting the common mistake of forgetting HCP has 6 atoms per unit cell. Option C is 1.5 times the correct value, playing on the intuition that HCP is similar to FCC but with different packing. Option D is double the correct value, targeting confusion between primitive and conventional unit cells in HCP structures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1748, "question": "During liquid-solid phase transformation, the heterogeneous nucleation barrier is related to the contact angle θ. When , the heterogeneous nucleation barrier is reduced by half compared to the homogeneous nucleation barrier. a.θ=0° b.θ=45° c.θ=90° d.θ=180°", "answer": "c", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项a、b、c、d中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对异质成核能垒与接触角关系的理解，需要应用基本公式和概念进行简单计算和判断，属于直接套用知识点的范畴。 | 难度: 在选择题型中，该题目属于简单难度。题目直接考察对异质形核能垒与接触角关系的理解，只需应用基本公式即可得出答案。解题步骤简单，无需复杂计算或公式变形，属于直接套用知识点的类型。", "convertible": true, "correct_option": "c.θ=90°", "choice_question": "During liquid-solid phase transformation, the heterogeneous nucleation barrier is related to the contact angle θ. When , the heterogeneous nucleation barrier is reduced by half compared to the homogeneous nucleation barrier.", "conversion_reason": "原题目已经是单选题格式，可以直接转换。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress for {110}<111> slip in BCC iron at 300K", "B": "The Peierls stress for {110}<111> slip in BCC iron at 300K", "C": "The theoretical shear strength of perfect BCC iron crystal", "D": "The yield strength of polycrystalline iron with 0.1% carbon" }, "correct_answer": "A", "explanation": "The correct answer is A because the critical resolved shear stress (CRSS) specifically measures the stress required to initiate slip on a particular slip system. Option B is a high-difficulty distractor that exploits confusion between CRSS and Peierls stress (which is the stress needed to move a dislocation through the crystal lattice). Option C traps those who confuse macroscopic yield with ideal crystal strength. Option D exploits the common tendency to conflate single crystal properties with polycrystalline behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3919, "question": "Which crystal system(s) listed below has (have) the following interaxial angle relationship?\n\\[\n\\alpha=\\beta=90^{\\circ}, \\gamma=120^{\\circ}\n\\](a) Cubic(b) Hexagonal(c) Tetragonal(d) Rhombohedral(e) Orthorhombic(f) Monoclinic(g) Triclinic", "answer": "Only the hexagonal crystal system has two of the interaxial angles equal to 90^{\\circ}, while the third angle is equal to 120^{\\circ}.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择符合特定晶体系统特征的正确答案 | 知识层次: 题目考查对晶体系统基本参数（轴角关系）的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要记忆不同晶系的轴角关系，但题目明确给出了具体的角度条件，只需将条件与各晶系的基本定义进行匹配即可。不需要复杂的分析或推导，属于基础概念理解和简单辨析的范畴。", "convertible": true, "correct_option": "b", "choice_question": "Which crystal system listed below has the following interaxial angle relationship?\n\\[\n\\alpha=\\beta=90^{\\circ}, \\gamma=120^{\\circ}\n\\]", "conversion_reason": "The original question is already in a multiple-choice format, and the answer specifies a single correct option (Hexagonal). Thus, it can be directly converted to a single-choice question by identifying the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The system exhibits negative thermal expansion due to rigid unit modes in the crystal structure", "B": "The system shows positive thermal expansion dominated by anharmonic atomic vibrations", "C": "The thermal expansion behavior is isotropic due to cubic symmetry", "D": "The material undergoes a phase transition that masks the intrinsic thermal expansion" }, "correct_answer": "A", "explanation": "Correct answer A exploits the counterintuitive nature of negative thermal expansion in certain crystal structures with rigid unit modes. Option B is a cognitive bias trap, as positive expansion is more common. Option C is a symmetry-based intuition trap, tempting AI to oversimplify. Option D is a multi-level verification trap requiring phase transition knowledge.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1420, "question": "What is the difference in the conduction mechanisms between intrinsic semiconductors and doped semiconductors?", "answer": "In intrinsic semiconductors, the charge carriers participating in conduction are electrons in the conduction band and an equal number of holes in the valence band, with the Fermi level located at the center of the band gap. In doped semiconductors, the charge carriers participating in conduction are electrons in the conduction band and an unequal number of holes in the valence band, with the Fermi level not located at the center of the band gap—either shifting upward (as in $\\mathbf{n}$-type semiconductors) or downward (as in p-type semiconductors).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述本征半导体和掺杂半导体的导电机制差异，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目考查半导体导电机制的基本概念，包括本征半导体和掺杂半导体的区别，以及费米能级的位置变化。这些内容属于材料科学中的基础概念记忆和理解范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题中属于较高难度，题目要求考生不仅理解并记忆本征半导体和掺杂半导体的基本定义，还需要掌握它们的导电机理差异，包括载流子类型、数量关系以及费米能级位置的变化。这涉及到多个概念的比较和综合分析，超出了简单的定义记忆或单一概念解释的范畴。", "convertible": true, "correct_option": "In intrinsic semiconductors, the charge carriers participating in conduction are electrons in the conduction band and an equal number of holes in the valence band, with the Fermi level located at the center of the band gap. In doped semiconductors, the charge carriers participating in conduction are electrons in the conduction band and an unequal number of holes in the valence band, with the Fermi level not located at the center of the band gap—either shifting upward (as in n-type semiconductors) or downward (as in p-type semiconductors).", "choice_question": "What is the difference in the conduction mechanisms between intrinsic semiconductors and doped semiconductors?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Intrinsic semiconductors rely solely on thermal excitation for carrier generation, while doped semiconductors use both thermal and impurity ionization", "B": "Doped semiconductors have higher carrier mobility due to reduced lattice scattering compared to intrinsic semiconductors", "C": "Intrinsic semiconductors exhibit ambipolar conduction, whereas doped semiconductors show unipolar conduction dominated by majority carriers", "D": "The conduction mechanism is identical in both, with differences only in carrier concentration magnitudes" }, "correct_answer": "C", "explanation": "Correct answer C captures the fundamental distinction: intrinsic semiconductors have equal electron and hole contributions (ambipolar), while doped semiconductors have one dominant carrier type (unipolar). Option A is partially correct but misses the key conduction mechanism difference. Option B exploits the common misconception that doping always improves mobility, ignoring ionized impurity scattering. Option D is a complete oversimplification trap that might appeal to AI's tendency to find unifying principles.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4874, "question": "What are the characteristics of investment casting technique?", "answer": "For investment casting, a single-piece mold is used, which is not reusable; it results in high dimensional accuracy, good reproduction of detail, and a fine surface finish; and casting rates are low.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释投资铸造技术的特点，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查对熔模铸造技术特点的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生理解并记忆投资铸造技术的基本特征，包括模具类型、尺寸精度、细节再现和表面光洁度等。虽然涉及多个知识点，但都属于基础概念记忆范畴，不需要复杂的分析或比较。因此，难度等级为2。", "convertible": true, "correct_option": "For investment casting, a single-piece mold is used, which is not reusable; it results in high dimensional accuracy, good reproduction of detail, and a fine surface finish; and casting rates are low.", "choice_question": "Which of the following are the characteristics of investment casting technique?", "conversion_reason": "The answer is a standard description of the characteristics of investment casting, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Uses a single-piece, non-reusable mold with high dimensional accuracy and fine surface finish", "B": "Employs reusable sand molds with moderate surface finish and high production rates", "C": "Utilizes permanent metal molds for rapid solidification and excellent mechanical properties", "D": "Combines ceramic shell molds with vacuum assistance for ultra-high purity castings" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes investment casting's key characteristics: single-use ceramic molds (lost-wax process), exceptional dimensional accuracy, and fine surface finish. Option B incorrectly describes sand casting attributes. Option C describes die casting features. Option D introduces vacuum assistance which is not standard in investment casting, creating a plausible-sounding but incorrect advanced variant.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 5, "correct_answers": 5, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4064, "question": "[d] Compared to other metals, like steel, pure aluminum is very resistant to failure via fatigue.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性（F表示错误），这是典型的判断题特征 | 知识层次: 题目考查对金属疲劳性能的基础概念记忆和理解，属于对纯铝与钢等金属疲劳性能差异的基本认知。 | 难度: 在选择题型中，此题属于基础概念正误判断，仅需记忆纯铝与钢在疲劳失效方面的基本特性对比即可作答，无需复杂分析或推理过程。", "convertible": true, "correct_option": "F", "choice_question": "[d] Compared to other metals, like steel, pure aluminum is very resistant to failure via fatigue.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect brittle fracture behavior under any loading conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While ceramics are generally brittle, some advanced ceramics can exhibit limited plasticity under specific conditions (e.g., high temperatures or hydrostatic pressure). The use of 'all' and 'any' makes this statement false, as it ignores these exceptions and the complex fracture behavior of ceramics under different conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4290, "question": "What is the magnitude of the maximum stress that exists at the tip of an internal crack having a radius of curvature of 2.5 × 10^{-4} mm\\left(10^{-5} in.\\right) and a crack length of 2.5 × 10^{-2} mm\\left(10^{-3} in.\\right) when a tensile stress of 170 MPa(25,000 psi) is applied?", "answer": "the magnitude of the maximum stress at the tip of the internal crack is 2404 \\text{ mpa} (354,000 \\text{ psi}).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定最大应力的数值，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及应力集中公式的应用和单位转换，需要理解裂纹尖端应力集中的基本原理，并能够正确应用公式进行计算。虽然不涉及复杂的综合分析或创新应用，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等难度，需要理解应力集中概念并进行多步计算。题目涉及裂纹尖端应力集中公式的应用（σ_m=2σ_0√(a/ρ)），需要正确代入半径和长度参数，并进行单位换算和开方运算。虽然计算步骤明确，但涉及多个变量的处理和MPa与psi单位的转换，对概念理解和计算准确性要求较高。", "convertible": true, "correct_option": "2404 MPa (354,000 psi)", "choice_question": "What is the magnitude of the maximum stress that exists at the tip of an internal crack having a radius of curvature of 2.5 × 10^{-4} mm (10^{-5} in.) and a crack length of 2.5 × 10^{-2} mm (10^{-3} in.) when a tensile stress of 170 MPa (25,000 psi) is applied?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2404 MPa (354,000 psi)", "B": "1700 MPa (250,000 psi)", "C": "850 MPa (125,000 psi)", "D": "340 MPa (50,000 psi)" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the stress concentration factor formula for an internal crack: σ_m = 2σ_0√(a/ρ), where σ_0 is the applied stress (170 MPa), a is the crack length (2.5 × 10^-2 mm), and ρ is the radius of curvature (2.5 × 10^-4 mm). Option B is a common mistake from incorrectly doubling the applied stress without considering crack geometry. Option C is half of B, appealing to those who misapply the stress concentration factor. Option D is simply the applied stress, targeting those who forget to account for stress concentration entirely.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1994, "question": "In the expression for calculating the force on dislocation motion, $f=\\tau b$, what does $\\tau$ refer to?", "answer": "The resolved shear stress of the external force in the slip direction on the slip plane.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释符号$\\tau$的含义，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对位错运动中基本概念的记忆和理解，即τ的定义和物理意义，属于基础概念记忆范畴。 | 难度: 该题目属于基础概念记忆类型，仅需回忆并识别$\\tau$的定义。在选择题型中，这种直接考查定义的问题属于最简单的难度等级，不需要复杂的分析或推理步骤。", "convertible": true, "correct_option": "The resolved shear stress of the external force in the slip direction on the slip plane.", "choice_question": "In the expression for calculating the force on dislocation motion, $f=\\tau b$, what does $\\tau$ refer to?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by providing the correct option and distractor options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The resolved shear stress of the external force in the slip direction on the slip plane", "B": "The maximum principal stress acting on the crystal lattice", "C": "The critical resolved shear stress required for dislocation nucleation", "D": "The hydrostatic stress component of the applied load" }, "correct_answer": "A", "explanation": "The correct answer is A because τ specifically refers to the component of external stress resolved in the slip direction on the slip plane. Option B is incorrect because it refers to principal stress which is not directly related to dislocation motion. Option C is a cognitive bias trap - while related to dislocations, it describes nucleation stress rather than motion stress. Option D exploits confusion between shear and hydrostatic stresses, where hydrostatic stress cannot drive dislocation glide.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3049, "question": "Ceramic materials have low tensile strength but high compressive strength.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（陶瓷材料具有低抗拉强度但高抗压强度），并要求判断其正确性（答案用√表示正确），这符合判断题的特征。 | 知识层次: 题目考查对陶瓷材料基本力学性能的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念正误判断题，仅需记忆陶瓷材料的基本力学特性（低抗拉强度、高抗压强度）即可作答。在选择题型中属于最简单的难度等级，不需要理解或分析复杂概念。", "convertible": true, "correct_option": "√", "choice_question": "Ceramic materials have low tensile strength but high compressive strength.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit higher hardness than all metallic materials under any conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While ceramics generally have higher hardness than metals, this is not universally true. Some specialty metallic alloys can surpass certain ceramics in hardness, especially under specific conditions or treatments. The use of 'all' and 'any' makes this statement incorrect due to these exceptions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 262, "question": "Explain the difference in diffusion coefficients of carbon in α-Fe and γ-Fe.", "answer": "The structure of the diffusion medium has a significant impact on diffusion. α-Fe has a body-centered cubic structure, while γ-Fe has a face-centered cubic structure. The body-centered cubic structure is more open than the face-centered cubic structure. A more open structure results in lower diffusion resistance and a higher diffusion coefficient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释碳在α-Fe和γ-Fe中扩散系数的差异，答案通过文字论述了晶体结构对扩散的影响，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求解释碳在α-Fe和γ-Fe中扩散系数的差异，需要理解晶体结构（体心立方和面心立方）对扩散的影响，并关联结构特征与扩散性能的关系。这涉及多个概念的关联和综合分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。虽然题目形式是选择题，但正确选项要求考生：", "convertible": true, "correct_option": "The body-centered cubic structure is more open than the face-centered cubic structure, resulting in lower diffusion resistance and a higher diffusion coefficient.", "choice_question": "What is the difference in diffusion coefficients of carbon in α-Fe and γ-Fe due to their structures?", "conversion_reason": "The answer is a standard explanation that can be rephrased as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The face-centered cubic structure has more interstitial sites, leading to higher carbon solubility but lower mobility", "B": "The body-centered cubic structure has higher atomic packing density, restricting carbon diffusion", "C": "Both structures have similar diffusion coefficients due to identical iron coordination numbers", "D": "The face-centered cubic structure has lower activation energy for carbon diffusion because of its higher symmetry" }, "correct_answer": "A", "explanation": "The correct answer is A because the FCC structure's higher number of interstitial sites increases carbon solubility but creates more energy barriers for diffusion. B is incorrect as BCC actually has lower packing density (68% vs 74% in FCC). C is wrong because coordination numbers differ (8 for BCC vs 12 for FCC). D is a symmetry fallacy - while FCC has higher symmetry, this doesn't directly correlate with diffusion activation energy.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 788, "question": "8.Sintering", "answer": "Sintering: A process in which one or more solid powders are formed and then heated to a certain temperature, causing them to shrink and become a dense, hard sintered body below the melting point temperature. Alternatively: Due to the mutual attraction of molecules (or atoms) in solids, heating causes the powder particles to bond, and through material migration and diffusion, the powder gains strength, leading to densification and recrystallization—this process is called sintering.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Sintering\"这一概念进行详细的文字解释和论述，答案提供了详细的定义和过程描述，符合简答题的特征。 | 知识层次: 题目考查烧结过程的基本定义和原理，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解和记忆烧结过程的基本定义和原理，包括粉末加热、收缩、致密化等关键步骤。虽然涉及多个概念，但都属于基础概念记忆层次，不需要复杂的分析或比较。因此，难度等级为2。", "convertible": true, "correct_option": "Sintering: A process in which one or more solid powders are formed and then heated to a certain temperature, causing them to shrink and become a dense, hard sintered body below the melting point temperature. Alternatively: Due to the mutual attraction of molecules (or atoms) in solids, heating causes the powder particles to bond, and through material migration and diffusion, the powder gains strength, leading to densification and recrystallization—this process is called sintering.", "choice_question": "下列关于Sintering的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Sintering involves atomic diffusion leading to neck formation between particles without reaching the melting point", "B": "Sintering requires the powder mixture to reach its eutectic temperature for effective bonding", "C": "The driving force for sintering is primarily the reduction of surface energy through particle coarsening", "D": "Liquid phase sintering always results in higher density than solid state sintering due to enhanced capillary forces" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental mechanism of solid-state sintering where atomic diffusion causes neck growth below melting point. B is wrong because eutectic temperature is only relevant for liquid phase sintering. C is partially correct but misleading - while surface energy reduction is the driving force, it occurs through densification (not coarsening). D is a common misconception - while liquid phase sintering often improves densification, the final density depends on multiple factors including dihedral angle and solubility.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 985, "question": "Both allotropic transformation and recrystallization transformation occur through nucleation and growth mechanisms. What are the differences between them?", "answer": "Allotropic transformation is a phase transition process, where the derivative of a certain thermodynamic quantity becomes discontinuous; recrystallization transformation is merely the reformation of grains and not a phase transition process.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述两种转变过程的区别，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目要求比较两种不同的相变机制（同素异构转变和再结晶转变），需要理解它们的本质区别，并能够关联相关概念进行综合分析。虽然涉及基础概念，但需要更深入的理解和应用能力来区分这两种机制。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求区分同素异构转变和再结晶转变这两种不同的相变过程，涉及对相变和再结晶的基本概念的理解，以及它们之间的差异。虽然题目没有涉及复杂的计算，但需要对材料科学中的相变和再结晶有清晰的认识，并能进行概念上的比较。因此，在选择题型内属于等级3的难度。", "convertible": true, "correct_option": "Allotropic transformation is a phase transition process, where the derivative of a certain thermodynamic quantity becomes discontinuous; recrystallization transformation is merely the reformation of grains and not a phase transition process.", "choice_question": "What are the differences between allotropic transformation and recrystallization transformation?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Allotropic transformation involves changes in crystal structure and is thermodynamically driven, while recrystallization only rearranges existing grains without phase change", "B": "Both processes are identical in mechanism but differ in driving forces: stress for recrystallization vs temperature for allotropic transformation", "C": "Recrystallization requires nucleation of new phases like allotropic transformation, but with different activation energies", "D": "The key difference lies in diffusion mechanisms: vacancy diffusion dominates recrystallization while interstitial diffusion controls allotropic transformation" }, "correct_answer": "A", "explanation": "Correct answer A precisely distinguishes the fundamental difference: allotropic transformation is a phase change process while recrystallization is a grain restructuring process. Option B exploits cognitive bias by suggesting identical mechanisms with different drivers. Option C creates professional intuition trap by incorrectly asserting recrystallization involves new phase nucleation. Option D sets a multi-level verification trap by introducing plausible but irrelevant diffusion mechanism differences.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4654, "question": "Calculate the radius of a palladium (P d) atom, given that P d has an FCC crystal structure, a density of 12.0g / {cm}^{3}, and an atomic weight of 106.4g / mol.", "answer": "the radius of a palladium (pd) atom is 0.138nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（FCC晶体结构、密度、原子重量等）来求解钯原子的半径，答案是一个具体的数值（0.138nm），符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及FCC晶体结构、密度和原子重量等概念的关联应用，需要综合分析能力来推导原子半径。 | 难度: 在选择题中属于中等偏上难度，需要综合运用晶体结构、密度、原子量等概念，并进行多步计算才能得出正确答案。虽然题目给出了正确选项，但解题过程涉及单位换算、晶格参数计算和原子半径推导等步骤，对学生的概念理解和计算能力要求较高。", "convertible": true, "correct_option": "0.138nm", "choice_question": "What is the radius of a palladium (Pd) atom, given that Pd has an FCC crystal structure, a density of 12.0g/cm³, and an atomic weight of 106.4g/mol?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.138nm", "B": "0.144nm", "C": "0.125nm", "D": "0.152nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.138nm) calculated using the FCC relationship between lattice parameter (a) and atomic radius (r=√2a/4), combined with density and atomic weight. Option B (0.144nm) is a common error from misapplying the BCC radius formula (r=√3a/4). Option C (0.125nm) exploits the tendency to confuse Pd with similar-weight elements like Ag. Option D (0.152nm) is designed to trap those who forget to convert units properly from cm³ to nm³ in density calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2913, "question": "After quenching 1.2% steel to obtain martensite and a small amount of retained austenite structure, what changes will occur when heated to 300°C and held for 2h?", "answer": "The retained austenite decomposes and transforms into α plus fine carbides, and the martensite also decomposes into α plus fine carbides, with the original martensite morphology becoming less distinct.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释热处理过程中组织变化的具体情况，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目要求分析淬火钢在回火过程中的组织转变，涉及马氏体和残余奥氏体的分解机制，需要综合运用相变原理和热处理知识进行推理分析，思维深度较高。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The retained austenite decomposes and transforms into α plus fine carbides, and the martensite also decomposes into α plus fine carbides, with the original martensite morphology becoming less distinct.", "choice_question": "After quenching 1.2% steel to obtain martensite and a small amount of retained austenite structure, what changes will occur when heated to 300°C and held for 2h?", "conversion_reason": "The answer is a specific and standard description of the changes that occur, making it suitable for conversion into a multiple-choice question where this description can be the correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The retained austenite transforms into pearlite while the martensite remains unchanged", "B": "Both the retained austenite and martensite decompose into ferrite and coarse cementite", "C": "The retained austenite decomposes into α plus fine carbides while martensite remains stable at this temperature", "D": "The retained austenite decomposes and transforms into α plus fine carbides, and the martensite also decomposes into α plus fine carbides, with the original martensite morphology becoming less distinct" }, "correct_answer": "D", "explanation": "The correct answer is D because at 300°C, both retained austenite and martensite undergo tempering transformations. Option A is incorrect because pearlite formation requires much higher temperatures and slower cooling. Option B is wrong as it describes over-tempering with coarse carbides, which occurs at higher temperatures. Option C is partially correct about austenite but wrong about martensite stability - this exploits the common misconception that low-temperature tempering doesn't affect martensite. Option D accurately describes the simultaneous decomposition processes at this temperature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2137, "question": "The nitriding temperature of steel is generally chosen to be close to but slightly below the eutectoid temperature of the Fe-N system (590°C), why?", "answer": "The reason is that the diffusion coefficient in α-Fe is higher than that in γ-Fe.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么钢的氮化温度选择接近但略低于Fe-N系统的共析温度（590°C），答案提供了文字解释和论述，说明在α-Fe中的扩散系数高于γ-Fe。这符合简答题的特征，需要文字解释而非选择、判断或计算。 | 知识层次: 题目不仅需要理解Fe-N系统的共析温度这一基础概念，还需要分析扩散系数在α-Fe和γ-Fe中的差异对氮化温度选择的影响，涉及材料相变和扩散机制的关联分析，思维过程较为深入。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The diffusion coefficient in α-Fe is higher than that in γ-Fe.", "choice_question": "The nitriding temperature of steel is generally chosen to be close to but slightly below the eutectoid temperature of the Fe-N system (590°C), why?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diffusion coefficient in α-Fe is higher than that in γ-Fe", "B": "To avoid the formation of brittle γ'-Fe4N phase", "C": "The solubility of nitrogen is maximized in the α-Fe phase", "D": "To maintain the steel's hardness by preventing austenite formation" }, "correct_answer": "A", "explanation": "The correct answer is A because the diffusion coefficient of nitrogen is indeed higher in ferrite (α-Fe) than in austenite (γ-Fe), which is critical for efficient nitriding. Option B is a cognitive bias trap - while γ'-Fe4N is brittle, it actually forms below the eutectoid temperature. Option C exploits intuitive thinking about solubility but is wrong because nitrogen solubility is higher in γ-Fe. Option D is a multi-level trap combining correct hardness considerations with incorrect reasoning about austenite formation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4198, "question": "State the Pauli exclusion principle.", "answer": "The Pauli exclusion principle states that each electron state can hold no more than two electrons, which must have opposite spins.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述一个科学原理（Pauli exclusion principle），答案是一个完整的句子解释，符合简答题的特征。 | 知识层次: 题目考查对泡利不相容原理这一基本概念的记忆和理解，属于定义性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆并复述泡利不相容原理的基本定义，属于最基础的概念记忆层次。题目仅涉及单一概念的直接表述，无需解释或复杂分析，因此难度等级为1。", "convertible": true, "correct_option": "The Pauli exclusion principle states that each electron state can hold no more than two electrons, which must have opposite spins.", "choice_question": "Which of the following correctly states the Pauli exclusion principle?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Pauli exclusion principle states that each electron state can hold no more than two electrons, which must have opposite spins", "B": "The Pauli exclusion principle states that no two electrons in an atom can have identical quantum numbers", "C": "The Pauli exclusion principle states that electrons fill atomic orbitals in order of increasing energy levels", "D": "The Pauli exclusion principle states that electrons preferentially occupy degenerate orbitals singly before pairing" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely states the Pauli exclusion principle's core concept of electron pairing with opposite spins in a single state. Option B is a common misconception - while related, this describes a consequence rather than the principle itself. Option C describes the Aufbau principle, exploiting conceptual proximity. Option D describes Hund's rule, using another quantum mechanics concept that often gets confused with Pauli's principle.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2692, "question": "Diamond is a crystalline form of carbon with a lattice constant α = 0.357 nm. When it transforms into the graphite (ρ = 2.25 g/cm³) structure, calculate the change in volume.", "answer": "The crystal structure of diamond is a complex face-centered cubic structure, with each unit cell containing a total of 8 carbon atoms. The density of diamond is $$ ρ = (8 × 12) / ((0.357 × 10⁻⁷)³ × 6.023 × 10²³) = 3.503 (g/cm³) $$. For 1 g of carbon, when it is in the diamond structure, its volume is $$ V₁ = 1 / 3.503 = 0.285 (cm³) $$. When it is in the graphite structure, its volume is $$ V₂ = 1 / 2.25 = 0.444 (cm³) $$. Therefore, the volume expansion when transforming from diamond to graphite is = (V₂ - V₁) / V₁ = (0.444 - 0.285) / 0.285 ≈ 55.8%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解体积变化，答案中包含了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括晶体结构分析、密度计算、体积转换和百分比变化计算。虽然不涉及复杂的推理或综合分析，但需要理解和应用多个概念，并进行关联计算。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、密度计算和体积变化的概念，并进行多步计算和综合分析。虽然题目提供了具体数值和公式，但解题过程涉及多个步骤和概念关联，对学生的计算能力和理解深度有一定要求。", "convertible": true, "correct_option": "55.8%", "choice_question": "Diamond is a crystalline form of carbon with a lattice constant α = 0.357 nm. When it transforms into the graphite (ρ = 2.25 g/cm³) structure, the change in volume is approximately:", "conversion_reason": "The original calculation question has a specific numerical answer (55.8%), which can be directly used as the correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice format by asking for the approximate change in volume.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "55.8%", "B": "42.3%", "C": "67.1%", "D": "33.5%" }, "correct_answer": "A", "explanation": "正确答案A(55.8%)是通过精确计算金刚石和石墨的摩尔体积比得出。干扰项B(42.3%)利用了常见错误计算方法(忽略石墨层间距)，C(67.1%)基于错误假设(完全忽略范德华间隙)，D(33.5%)则采用了错误的密度换算方法。这些干扰项都利用了材料计算中典型的认知偏差和直觉陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2443, "question": "For a ceramic oxide, in which temperature ranges does the vacancy diffusion mechanism occur as intrinsic or extrinsic?", "answer": "If the ceramic oxide is a solid solution, the incorporation of solutes with different valences will generate extrinsic point defects. The concentration of intrinsic point defects changes drastically with temperature, while the concentration of extrinsic point defects does not vary with temperature. Therefore, at low temperatures, the concentration of extrinsic vacancies is higher than that of intrinsic vacancies, and this difference becomes more pronounced as the temperature decreases. Thus, in the low-temperature range, the extrinsic vacancy diffusion mechanism dominates.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释陶瓷氧化物中空位扩散机制在何种温度范围内表现为本征或外征，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要综合运用点缺陷理论、温度对缺陷浓度的影响以及扩散机制的知识，进行推理分析和机理解释。涉及多个概念的关联和综合分析，思维过程较为深入。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生综合运用陶瓷氧化物中本征与非本征点缺陷的知识，理解不同温度范围内扩散机制的主导因素，并能够分析掺杂价态对缺陷浓度的影响。解题需要：", "convertible": true, "correct_option": "At low temperatures, the extrinsic vacancy diffusion mechanism dominates.", "choice_question": "For a ceramic oxide, in which temperature range does the extrinsic vacancy diffusion mechanism dominate?", "conversion_reason": "The answer is a specific statement that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by focusing on the key concept of temperature ranges for diffusion mechanisms.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "At low temperatures, where impurity concentrations control vacancy formation", "B": "At intermediate temperatures, where both intrinsic and extrinsic mechanisms contribute equally", "C": "At high temperatures, where thermal energy overcomes intrinsic defect formation energy", "D": "Across all temperature ranges, as vacancy diffusion is temperature-independent" }, "correct_answer": "A", "explanation": "The correct answer is A because extrinsic vacancy diffusion dominates at low temperatures where impurity concentrations (rather than thermal energy) primarily control vacancy formation. Option B is a cognitive bias trap - while both mechanisms may coexist, they never contribute equally. Option C exploits professional intuition by describing intrinsic (not extrinsic) diffusion behavior. Option D is a fundamental misconception trap, suggesting vacancy diffusion has no temperature dependence.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 914, "question": "5. Secondary recrystallization", "answer": "A phenomenon where the normal growth process is inhibited after recrystallization, leading to abnormal growth of a few grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Secondary recrystallization\"这一现象进行文字解释和论述，答案是一个描述性的定义，符合简答题的特征。 | 知识层次: 题目考查对二次再结晶这一基本现象的定义和描述，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆，但需要考生准确理解\"二次再结晶\"的定义特征（正常晶粒生长被抑制、少数晶粒异常长大），这比单纯记忆术语名称（等级1）要求更高。题目正确选项完整描述了现象的本质特征，属于概念解释和描述层面的考查，符合等级2的难度标准。", "convertible": true, "correct_option": "A phenomenon where the normal growth process is inhibited after recrystallization, leading to abnormal growth of a few grains.", "choice_question": "Which of the following best describes secondary recrystallization?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A phenomenon where the normal growth process is inhibited after recrystallization, leading to abnormal growth of a few grains", "B": "The second stage of primary recrystallization where smaller grains continue to grow uniformly", "C": "A process where previously recrystallized grains undergo further phase transformation", "D": "The selective dissolution of grain boundaries leading to porous microstructure formation" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines secondary recrystallization as abnormal grain growth after inhibited normal growth. Option B exploits the 'recrystallization' cognitive bias by suggesting a continuation of primary process. Option C uses phase transformation as a professional intuition trap, while D creates a multi-level verification trap by combining grain boundary phenomena with porosity formation, both real but unrelated concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4093, "question": "For a fibrous composite with fibers that are uniformly distributed and randomly oriented in all directions, when a stress is applied in any direction, what is the reinforcement efficiency?(a) 0(b) \\frac{1}{{ }_{5}}(c) \\frac{3}{8}(d) \\frac{3}{{ }_{4}}(e) 1", "answer": "For a fibrous composite with fibersthat are uniformly distributed and randomly oriented in all directions, when a stress is applied in any direction, the reinforcement efficiency is 1 / 5.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项(a)-(e)中选择关于纤维增强复合材料增强效率的正确答案 | 知识层次: 题目考查对纤维复合材料增强效率的基本理解和简单应用，需要记忆随机取向纤维的增强效率值，并选择正确的选项。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接套用基本公式或概念即可得出答案。题目明确给出了纤维复合材料在随机取向情况下的增强效率，学生只需记忆或简单应用这一知识点即可选择正确答案，无需进行复杂的计算或变形。因此，在选择题型内属于较低难度。", "convertible": true, "correct_option": "(b) \\frac{1}{{ }_{5}}", "choice_question": "For a fibrous composite with fibers that are uniformly distributed and randomly oriented in all directions, when a stress is applied in any direction, what is the reinforcement efficiency?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer among the provided options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The efficiency is 1/3 due to isotropic averaging of Young's modulus", "B": "The efficiency is 1/5 as derived from orientation averaging of stiffness tensor", "C": "The efficiency is 3/8 based on Voigt-Reuss-Hill approximation", "D": "The efficiency is 1/2 considering only axial loading components" }, "correct_answer": "B", "explanation": "The correct answer is B (1/5) because for randomly oriented fibers, the reinforcement efficiency is determined by orientation averaging of the stiffness tensor components, specifically the (1,1) component. Option A is a cognitive bias trap using isotropic elastic modulus averaging which doesn't apply to reinforcement efficiency. Option C exploits the common Voigt-Reuss-Hill approximation which is irrelevant here. Option D is a professional intuition trap that incorrectly assumes only axial components contribute.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4018, "question": "Is frozen water with trapped air bubbles a two-phase material system?", "answer": "Yes, it is a two-phase system because there is a physical boundary beyond the particle level that separates chemically and structurally distinct volumes.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（\"Is frozen water with trapped air bubbles a two-phase material system?\"），答案直接给出了判断结果（\"Yes\"）并提供了简要解释。这符合判断题的特征。 | 知识层次: 题目考查对两相材料系统基本概念的理解和判断，属于基础概念记忆范畴，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目直接考察对\"两相材料系统\"定义的理解，只需判断是否存在物理边界和化学/结构差异这两个基本要素。正确选项明确给出了定义性描述，不需要进行复杂分析或概念比较，符合等级1的简单记忆性知识考查要求。", "convertible": true, "correct_option": "Yes, it is a two-phase system because there is a physical boundary beyond the particle level that separates chemically and structurally distinct volumes.", "choice_question": "Is frozen water with trapped air bubbles a two-phase material system?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, some advanced ceramics like transformation-toughened zirconia can exhibit significant plasticity due to stress-induced phase transformations. The use of 'all' makes this statement incorrect.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2473, "question": "A low-alloy steel ingot containing silicon exhibits dendritic segregation with a dendrite arm spacing of 500μm. After diffusion annealing at 1200°C, the segregation amplitude is reduced to 10% of its original value. How long should the holding time be for the silicon element? Assume the diffusion coefficient of silicon in austenite at 1200°C is 7.03×10^(-11)cm^2/s.", "answer": "When dendritic segregation exists, the solute composition is distributed with the dendrite arm spacing as the period, where the period l is 500μm=0.05cm. According to the trigonometric series solution of the diffusion equation, the concentration amplitude decays with a decay factor, i.e., C=C¯+C0sin(πx/l)exp(-π^2Dt/l^2). If the amplitude decays to 1/10 of its original value, then exp(-π^2Dt/l^2)=0.1. Therefore, the required time for the Si element is: t=l^2/(π^2D)ln0.1=-(0.025)^2/(π^2×7.03×10^(-11))ln0.1s=2.07×10^6s. Since Si in Fe is a substitutional solute atom while C is an interstitial solute atom, the diffusion rate of Si atoms is much slower than that of C, so the homogenization time for Si is several orders of magnitude slower than that for C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解硅元素的保温时间，答案中包含了具体的计算过程和数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括理解扩散方程的三角级数解、计算衰减因子、求解时间等。同时需要理解枝晶偏析的概念和扩散系数的影响，涉及概念关联和综合分析。虽然不涉及复杂的机理分析或创新设计，但计算过程较为复杂，超出了简单应用的范畴。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程的解、三角函数级数解、衰减因子等概念，并进行多步计算（包括对数运算和单位转换）。虽然题目提供了关键参数，但需要综合运用材料科学和数学知识才能正确求解。相比单纯的概念选择题，这类计算题在选择题型中属于较复杂的类型。", "convertible": true, "correct_option": "2.07×10^6s", "choice_question": "A low-alloy steel ingot containing silicon exhibits dendritic segregation with a dendrite arm spacing of 500μm. After diffusion annealing at 1200°C, the segregation amplitude is reduced to 10% of its original value. How long should the holding time be for the silicon element? Assume the diffusion coefficient of silicon in austenite at 1200°C is 7.03×10^(-11)cm^2/s.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.07×10^6s", "B": "1.04×10^6s", "C": "4.14×10^6s", "D": "5.18×10^5s" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算扩散时间得到的正确结果。干扰项B设计为正确答案的一半，利用了计算中可能忽略平方关系的认知偏差。干扰项C是正确答案的两倍，针对可能错误理解衰减关系的直觉陷阱。干扰项D是正确答案的四分之一，利用了单位换算或系数遗漏的常见错误。所有干扰项都保持相同数量级，增加选择难度。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4180, "question": "Give the electron configuration for the ion Cu+.", "answer": "The electron configuration for a Cu+ ion is 1s2 2s2 2p6 3s2 3p6 3d10.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求给出Cu+离子的电子排布，需要文字解释和论述，而不是从选项中选择或判断对错，也不需要数值计算。 | 知识层次: 题目考查对电子排布基本概念的记忆和理解，仅需直接回忆铜离子(Cu+)的电子构型，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求记忆铜离子(Cu+)的电子排布，但需要掌握过渡金属离子的电子排布特点，特别是铜的例外情况（4s电子先填充但3d轨道未填满）。这超出了简单的定义记忆，需要对电子排布规则有一定理解和应用能力。", "convertible": true, "correct_option": "1s2 2s2 2p6 3s2 3p6 3d10", "choice_question": "What is the electron configuration for the ion Cu+?", "conversion_reason": "The answer is a standard and specific electron configuration, which can be presented as a correct option among other plausible but incorrect configurations.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1s2 2s2 2p6 3s2 3p6 3d10", "B": "1s2 2s2 2p6 3s2 3p6 3d9 4s1", "C": "1s2 2s2 2p6 3s2 3p6 3d8 4s2", "D": "1s2 2s2 2p6 3s2 3p6 3d9 4s2" }, "correct_answer": "A", "explanation": "正确答案A是Cu+的电子排布，因为Cu原子失去一个电子时，优先从4s轨道失去电子，留下完全填充的3d轨道。干扰项B利用了Cu原子的基态电子构型(3d10 4s1)的认知偏差，让人误以为离子态也保持这种构型。干扰项C和D设计了部分填充的3d轨道构型，利用了人们对过渡金属离子常见电子构型的直觉判断，但忽略了Cu+的特殊稳定性来自完全填充的d轨道。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1812, "question": "The viscosity corresponding to the glass transition temperature Tg is a.108dPa·s b.1010dPa·s c.1011dPa·s d.1013dPa·s", "answer": "d", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的四个选项中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查对玻璃转变温度Tg对应粘度值的记忆，属于基础概念的记忆性知识 | 难度: 该题目属于基础概念记忆类型，仅需直接回忆玻璃转变温度Tg对应的粘度数值即可选出正确答案。在选择题型中，这种仅需简单记忆的知识点属于最低难度等级。", "convertible": true, "correct_option": "d.1013dPa·s", "choice_question": "The viscosity corresponding to the glass transition temperature Tg is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress for dislocation motion in pure aluminum at room temperature", "B": "The yield strength of fully annealed copper single crystal", "C": "The Peierls-Nabarro stress for edge dislocations in bcc iron", "D": "The theoretical shear strength of a perfect crystal lattice" }, "correct_answer": "A", "explanation": "The correct answer is A because the critical resolved shear stress (CRSS) for dislocation motion in pure aluminum at room temperature is a well-documented material property (~0.5-1 MPa). Option B is a cognitive bias trap - while yield strength seems related, single crystal properties differ significantly from polycrystalline values. Option C exploits professional intuition by referencing the Peierls-Nabarro stress which is much higher (~1 GPa) but specific to bcc iron. Option D is a multi-level verification trap - while theoretically correct (G/2π), it's orders of magnitude higher than practical dislocation motion stresses.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1549, "question": "1. Pearlitic transformation", "answer": "The phase transformation in which the austenite of Fe-C alloy simultaneously transforms into the eutectoid structure of ferrite and cementite below the eutectoid transformation temperature during cooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对珠光体相变进行文字解释和论述，答案提供了详细的定义和过程描述，符合简答题的特征。 | 知识层次: 题目考查对珠光体转变这一基本概念的定义和描述，属于基础概念的记忆和理解层面 | 难度: 该题目属于选择题型中的概念解释和描述难度等级。题目要求考生准确记忆并理解珠光体转变的定义，即奥氏体在共析转变温度以下同时转变为铁素体和渗碳体的共析结构。虽然涉及专业术语，但属于材料科学基础概念，不需要复杂的分析或比较，只需准确回忆定义即可作答。在选择题型中，这属于中等偏下的难度水平。", "convertible": true, "correct_option": "The phase transformation in which the austenite of Fe-C alloy simultaneously transforms into the eutectoid structure of ferrite and cementite below the eutectoid transformation temperature during cooling.", "choice_question": "Which of the following best describes pearlitic transformation?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct definition as one of the options and other plausible but incorrect definitions as distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phase transformation in which the austenite of Fe-C alloy simultaneously transforms into the eutectoid structure of ferrite and cementite below the eutectoid transformation temperature during cooling.", "B": "The diffusionless martensitic transformation that occurs in Fe-C alloys when rapidly quenched below the martensite start temperature.", "C": "The precipitation of cementite from supersaturated ferrite during aging of low-carbon steels at intermediate temperatures.", "D": "The discontinuous decomposition of austenite into alternating layers of ferrite and cementite that occurs only in hypereutectoid steels." }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the simultaneous formation of ferrite and cementite from austenite at the eutectoid point. Option B incorrectly describes martensitic transformation, exploiting confusion between diffusion-based and diffusionless transformations. Option C describes a precipitation process rather than eutectoid transformation, targeting confusion between different phase change mechanisms. Option D introduces a specific but incorrect condition (hypereutectoid steels only), playing on the common misconception about pearlite formation range.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2708, "question": "At 700°C, what is the proportion of atoms with sufficient energy?", "answer": "According to the Arrhenius equation, ln C = ln A - E/kT. Given ln A = -2.92, E = 2.14×10^(-19) J, k = 1.38×10^(-23) J/K, and T = 973 K. Substituting these values yields ln C = -2.92 - (2.14×10^(-19))/(1.38×10^(-23)×973). The calculation gives C = n/N = 6×10^(-9).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（Arrhenius方程）来求解特定温度下具有足够能量的原子比例，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目需要应用Arrhenius方程进行多步计算，涉及对数运算和指数转换，需要理解方程中各参数的含义及其相互关系，并进行综合计算。虽然不涉及复杂的推理分析或创新应用，但计算过程较为复杂，超出了简单应用的范畴。 | 难度: 在选择题中属于中等偏上难度，需要理解阿伦尼乌斯方程并正确代入多个变量进行计算。题目涉及多步骤计算过程，包括对数运算和指数转换，同时需要综合理解能量、温度和比例之间的关系。虽然题目提供了所有必要参数，但计算过程较为复杂，需要较高的注意力以避免错误。", "convertible": true, "correct_option": "6×10^(-9)", "choice_question": "At 700°C, what is the proportion of atoms with sufficient energy according to the Arrhenius equation, given ln A = -2.92, E = 2.14×10^(-19) J, k = 1.38×10^(-23) J/K, and T = 973 K?", "conversion_reason": "The calculation yields a specific numerical answer, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6×10^(-9)", "B": "1.2×10^(-8)", "C": "3×10^(-10)", "D": "9×10^(-7)" }, "correct_answer": "A", "explanation": "正确答案A是通过严格应用Arrhenius方程计算得出的精确值。干扰项B利用了温度单位转换的认知偏差（未将700°C正确转换为973K），干扰项C利用了指数计算中常见的符号错误（将正指数误为负指数），干扰项D则利用了材料科学中常见的高温近似值直觉（但在此情境下严重高估）。每个干扰项都针对AI模型在科学计算中常见的特定错误模式设计。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4593, "question": "(a) Briefly explain why Cv rises with increasing temperature at temperatures near 0 K.", "answer": "The reason that Cv rises with increasing temperature at temperatures near 0 K is because, in this temperature range, the allowed vibrational energy levels of the lattice waves are far apart relative to the available thermal energy, and only a portion of the lattice waves may be excited. As temperature increases, more of the lattice waves may be excited by the available thermal energy, and, hence, the ability of the solid to absorb energy (i.e., the magnitude of the heat capacity) increases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释Cv在接近0 K时随温度升高的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释Cv在接近0 K时随温度升高的原因，涉及晶格振动能级的激发和热能的相互作用，需要综合运用固体物理和热力学知识进行机理分析和推理。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解晶格振动的基本概念，还需要掌握在接近0K温度下量子化能级的热激发机制。正确选项涉及对固体热容随温度变化的微观机理的深入解释，需要综合运用统计物理和固体物理知识进行推理分析。这种复杂现象的解释在选择题型中属于对知识掌握深度和综合分析能力要求最高的类型。", "convertible": true, "correct_option": "The reason that Cv rises with increasing temperature at temperatures near 0 K is because, in this temperature range, the allowed vibrational energy levels of the lattice waves are far apart relative to the available thermal energy, and only a portion of the lattice waves may be excited. As temperature increases, more of the lattice waves may be excited by the available thermal energy, and, hence, the ability of the solid to absorb energy (i.e., the magnitude of the heat capacity) increases.", "choice_question": "Why does Cv rise with increasing temperature at temperatures near 0 K?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The increasing thermal energy allows excitation of higher frequency phonon modes that were previously frozen out", "B": "The lattice vibrations begin to overcome the Debye temperature limit at these low temperatures", "C": "The electronic contribution to heat capacity becomes dominant as temperature approaches 0 K", "D": "The anharmonicity of atomic vibrations increases significantly near absolute zero" }, "correct_answer": "A", "explanation": "The correct answer is A because near 0 K, only low-energy phonon modes are excited, and as temperature increases, higher frequency modes become accessible, increasing Cv. Option B is incorrect because the Debye temperature is not a hard limit to be overcome. Option C is wrong because electronic contributions are negligible in this temperature range for non-metals. Option D is incorrect because anharmonic effects decrease, not increase, at low temperatures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1138, "question": "What is the movement of dislocations on the slip plane called?", "answer": "Slip", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用简短的文字回答特定概念的定义或名称，不需要选择或判断，也不需要计算 | 知识层次: 题目考查的是对位错运动的基本概念的记忆和理解，即滑移的定义，属于基础概念记忆性知识。 | 难度: 在选择题型中，此题仅考察对\"滑移\"这一基础定义的单点记忆，不需要解释或比较其他概念。属于最基础的定义简答级别，符合等级1的简单记忆要求。", "convertible": true, "correct_option": "Slip", "choice_question": "What is the movement of dislocations on the slip plane called?", "conversion_reason": "The answer is a standard term in the field, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip", "B": "Twinning", "C": "Dislocation climb", "D": "Grain boundary sliding" }, "correct_answer": "A", "explanation": "The correct answer is A (Slip) because it specifically refers to the movement of dislocations along slip planes under shear stress. Option B (Twinning) is a deformation mechanism involving mirror-image lattice reorientation, not dislocation movement. Option C (Dislocation climb) exploits the common confusion with edge dislocation motion perpendicular to the slip plane. Option D (Grain boundary sliding) targets the misconception that all deformation occurs at boundaries rather than within grains.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3170, "question": "Two edge dislocations with opposite signs on the same slip plane have Burgers vectors of b. If they approach infinitely close, what is the total energy?", "answer": "When two edge dislocations with opposite signs approach infinitely close, they annihilate each other, and the total energy becomes zero.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案是对现象的解释而非计算或选择 | 知识层次: 题目考查对位错湮灭这一基本概念的记忆和理解，不需要复杂的计算或分析，只需知道当两个符号相反的刃位错无限接近时会相互湮灭，总能量变为零。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接考察对位错湮灭现象的基础概念记忆，只需知道相反符号的刃位错在无限接近时会相互湮灭，总能量变为零这一基本原理即可作答，无需复杂推理或多步骤分析。", "convertible": true, "correct_option": "When two edge dislocations with opposite signs approach infinitely close, they annihilate each other, and the total energy becomes zero.", "choice_question": "Two edge dislocations with opposite signs on the same slip plane have Burgers vectors of b. If they approach infinitely close, what is the total energy?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The total energy becomes zero due to annihilation", "B": "The total energy equals 2Gb² where G is the shear modulus", "C": "The total energy approaches infinity due to stress field superposition", "D": "The total energy equals the sum of individual dislocation line energies" }, "correct_answer": "A", "explanation": "The correct answer is A because opposite sign dislocations on the same slip plane will annihilate when brought together, resulting in zero energy. Option B is a cognitive bias trap, using the correct formula for a single dislocation's energy but ignoring the annihilation effect. Option C exploits intuition about stress fields but fails to consider cancellation. Option D is a professional intuition trap, appealing to the common practice of summing energies while overlooking the special case of annihilation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2627, "question": "What does the short-range structure (primary structure) of polymer chain include?", "answer": "Chemical structure, atomic arrangement in the molecular chain, bonding sequence of structural units, branching, cross-linking, etc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释聚合物链的短程结构（一级结构）包括哪些内容，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对聚合物短程结构（一级结构）基本组成要素的记忆和理解，属于基础概念范畴 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项包含了多个具体知识点（化学结构、分子链中的原子排列、结构单元的键合序列、支化、交联等），需要考生对聚合物短程结构的多个方面有较为全面的理解和记忆。相较于仅考察单一基本定义的题目（等级1），该题目要求考生能够综合掌握并区分多个相关概念，因此难度稍高。", "convertible": true, "correct_option": "Chemical structure, atomic arrangement in the molecular chain, bonding sequence of structural units, branching, cross-linking, etc.", "choice_question": "What does the short-range structure (primary structure) of polymer chain include?", "conversion_reason": "The answer is a standard list of terms and concepts, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chemical structure and atomic arrangement only", "B": "Molecular weight distribution and polydispersity index", "C": "Crystallinity degree and spherulite size", "D": "Chemical structure, atomic arrangement, bonding sequence, branching, and cross-linking" }, "correct_answer": "D", "explanation": "The correct answer D comprehensively covers all aspects of primary structure including chemical structure, atomic arrangement, bonding sequence, branching, and cross-linking. Option A is incomplete as it misses key structural features. Option B describes polymer characteristics rather than primary structure. Option C refers to higher-order morphology properties, not the primary chain structure. The distractors exploit common misconceptions about structural hierarchy in polymers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1959, "question": "What are the conditions for forming an infinite solid solution?", "answer": "The same crystal structure of the two components is a necessary condition for forming an infinite solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释形成无限固溶体的条件，答案提供了文字解释和论述，符合简答题的特征 | 知识层次: 题目考查对无限固溶体形成条件的基本概念记忆和理解，主要涉及晶体结构相同这一必要条件的知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅考察对无限固溶体形成条件的必要条件的记忆，即两种组分具有相同的晶体结构。不需要解释或分析其他因素，属于最基础的概念记忆层次。", "convertible": true, "correct_option": "The same crystal structure of the two components is a necessary condition for forming an infinite solid solution.", "choice_question": "Which of the following is a necessary condition for forming an infinite solid solution?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The two components have identical atomic radii within 5% tolerance", "B": "The two components exhibit complete liquid miscibility at all temperatures", "C": "The two components have the same crystal structure and electronegativity values", "D": "The two components show negative deviation from Vegard's law in their phase diagram" }, "correct_answer": "C", "explanation": "The correct answer is C because having the same crystal structure is a fundamental requirement for infinite solid solubility, and similar electronegativity prevents compound formation. Option A is a cognitive bias trap - while atomic size similarity is important, it's not sufficient alone. Option B exploits professional intuition by suggesting liquid miscibility implies solid solubility, which is incorrect. Option D is a multi-level verification trap using a real but irrelevant phenomenon (Vegard's law deviation doesn't determine solubility limits).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 745, "question": "In the face-centered cubic crystal structure, the close-packed plane is (7)", "answer": "{111} plane", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的知识点（面心立方晶体结构中的密排面），答案是一个特定的晶体学平面（{111} plane），不需要计算或选择，属于简答题类型 | 知识层次: 题目考查面心立方晶体结构中密排面的记忆，属于基础概念的记忆性知识 | 难度: 在选择题型中，此题属于基础概念记忆类型，仅需考生记住面心立方晶体结构中密排面的晶面指数{111}即可作答。题目不涉及任何概念解释或复杂分析过程，完全基于对基本定义的直接回忆，因此属于最简单的难度等级1。", "convertible": true, "correct_option": "{111} plane", "choice_question": "In the face-centered cubic crystal structure, the close-packed plane is:", "conversion_reason": "The answer is a standard terminology in crystallography, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "{111} plane", "B": "{110} plane", "C": "{100} plane", "D": "{112} plane" }, "correct_answer": "A", "explanation": "The {111} plane is the close-packed plane in FCC structures because it has the highest atomic packing density. Option B ({110}) is a common trap as it appears in BCC structures. Option C ({100}) exploits surface energy misconceptions. Option D ({112}) targets confusion with twinning planes in BCC metals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2194, "question": "Given that the elastic modulus of sintered alumina is $370\\\\mathrm{GPa}$ when its porosity is $5\\\\%$, if the elastic modulus of another sintered alumina is $270~\\\\mathrm{GPa}$, calculate its porosity.", "answer": "The relationship between the elastic modulus $E$ of ceramic materials and their pore volume fraction $\\\\varphi$ can be expressed as $$ E=E_{\\\\circ}(1-1.9\\\\varphi+0.9\\\\varphi^{2}) $$ where $E_{0}$ is the elastic modulus of the material without pores. Given that when $\\\\varphi=0.05$, $E=370~\\\\mathrm{GPa}$, thus $$ E_{\\\\circ}={\\\\frac{E}{1-1.9{\\\\varphi}+0.9{\\\\varphi}^{2}}}={\\\\frac{370}{1-1.9\\\\times0.05+0.9\\\\times(0.05)^{2}}}=407.8{\\\\mathrm{~GPa}} $$ When $E=270$ GPa, $$ 270=407.8(1-1.9\\\\varphi+0.9\\\\varphi^{2}) $$ which simplifies to $$ 0.9\\\\varphi^{2}-1.9\\\\varphi+0.338=0 $$ Therefore, $$ \\\\varphi=0.196=19.6\\\\% $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和数值计算另一个烧结氧化铝的孔隙率，解答过程涉及数值计算和公式应用。 | 知识层次: 题目需要进行多步计算，包括公式的推导和数值求解，涉及弹性模量与孔隙率之间的非线性关系，需要一定的综合分析能力。虽然不涉及复杂的机理分析或创新设计，但超出了简单直接套用公式的范围。 | 难度: 在选择题中属于中等偏上难度，需要理解弹性模量与孔隙率的关系公式，并进行多步计算。首先需要根据已知条件求解无孔隙时的弹性模量E0，然后代入新的弹性模量值建立方程，最后解二次方程得到孔隙率。整个过程涉及公式推导、数值计算和方程求解，但题目提供了完整的解题思路，降低了部分难度。", "convertible": true, "correct_option": "19.6%", "choice_question": "Given that the elastic modulus of sintered alumina is $370\\mathrm{GPa}$ when its porosity is $5\\%$, if the elastic modulus of another sintered alumina is $270~\\mathrm{GPa}$, what is its porosity?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "19.6%", "B": "14.2%", "C": "27.0 GPa", "D": "5.0%" }, "correct_answer": "A", "explanation": "正确答案A是通过弹性模量与孔隙率的指数关系公式计算得出。干扰项B利用线性近似计算产生的认知偏差，数值接近但错误。干扰项C故意混淆弹性模量单位与孔隙率百分比的概念。干扰项D利用原始条件数据制造直觉陷阱，让AI忽略需要计算的事实。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1446, "question": "For a screw dislocation line, what is the relationship between its cross-slip motion direction and the Burgers vector?", "answer": "Perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释螺丝位错线的交叉滑移运动方向与伯格斯矢量之间的关系，答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目考查对螺位错基本性质的理解，即其交叉滑移运动方向与Burgers向量的关系，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别螺位错线的交叉滑移运动方向与伯格斯矢量之间的基本关系（垂直）。这属于基础概念记忆层次，无需解释或分析，只需直接回忆定义即可作答。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Perpendicular", "choice_question": "For a screw dislocation line, what is the relationship between its cross-slip motion direction and the Burgers vector?", "conversion_reason": "The answer is a standard term (Perpendicular), which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Parallel", "B": "Perpendicular", "C": "At 45 degrees", "D": "Depends on the slip plane orientation" }, "correct_answer": "B", "explanation": "The correct answer is B (Perpendicular) because cross-slip of a screw dislocation occurs when the dislocation moves from one slip plane to another parallel slip plane, requiring the motion direction to be perpendicular to the Burgers vector. Option A is a cognitive bias trap exploiting the common misconception that screw dislocation motion is always parallel to its Burgers vector. Option C is a professional intuition trap using an angle that appears plausible for mixed dislocations. Option D is a multi-level verification trap that seems correct at first glance but ignores the fundamental requirement for cross-slip geometry.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4358, "question": "In terms of heat treatment and the development of microstructure, what is one major limitation of the iron-iron carbide phase diagram related to nonequilibrium phases?", "answer": "The nonequilibrium martensite does not appear on the diagram.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释铁-碳相图的一个主要局限性，并需要文字论述，答案也是以文字形式给出解释，符合简答题的特征 | 知识层次: 题目要求理解铁-碳相图的基本原理，并能够分析其在非平衡相变中的局限性，涉及概念关联和综合分析。虽然不涉及多步计算，但需要对相图和实际热处理过程的关系有较深入的理解。 | 难度: 在选择题中属于中等难度，需要理解铁-碳相图的基本概念，并能够关联非平衡相（如马氏体）的形成条件与相图的局限性。虽然不涉及多步计算，但需要对相图的应用范围和局限性有较深入的理解，并进行综合分析。", "convertible": true, "correct_option": "The nonequilibrium martensite does not appear on the diagram.", "choice_question": "In terms of heat treatment and the development of microstructure, what is one major limitation of the iron-iron carbide phase diagram related to nonequilibrium phases?", "conversion_reason": "The answer is a standard concept or term, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diagram fails to account for the formation of pearlite under rapid cooling conditions", "B": "The nonequilibrium martensite does not appear on the diagram", "C": "The diagram inaccurately represents the solubility limit of carbon in austenite", "D": "The eutectoid reaction temperature is shown incorrectly for high cooling rates" }, "correct_answer": "B", "explanation": "The correct answer is B because the iron-iron carbide phase diagram is an equilibrium diagram and does not show nonequilibrium phases like martensite. Option A is incorrect because pearlite is an equilibrium phase product. Option C is a trap exploiting the common misconception about solubility limits changing with cooling rate. Option D uses a plausible-sounding but incorrect statement about eutectoid reaction temperature dependence on cooling rates.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2721, "question": "If the positive direction of a dislocation line is defined as the original opposite direction, does the type and nature of the dislocation change?", "answer": "The type and nature of this dislocation do not change.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（dislocation的类型和性质是否改变），答案直接给出了对错判断（不改变） | 知识层次: 题目考查对位错线方向和位错类型及性质的基本概念的理解，属于基础概念记忆范畴。 | 难度: 该题目属于基本概念正误判断，仅需记忆和理解位错线方向定义对位错类型和性质的影响即可作答，无需复杂分析或推理过程。在选择题型中属于最基础的难度等级。", "convertible": true, "correct_option": "The type and nature of this dislocation do not change.", "choice_question": "If the positive direction of a dislocation line is defined as the original opposite direction, does the type and nature of the dislocation change?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all crystalline materials, the Burgers vector magnitude is always an integer multiple of the lattice parameter.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the Burgers vector is often an integer multiple of the lattice parameter in simple cubic structures, this is not universally true for all crystalline materials. In complex crystal structures or when partial dislocations are present, the Burgers vector can be a fraction of the lattice parameter. This question tests understanding of dislocation fundamentals and challenges the common oversimplification about Burgers vectors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4046, "question": "For an n-type semiconductor, which type of charge carrier is present in the greater concentration?(a) Hole(b) Electron", "answer": "For an n-type semiconductor, electrons (i.e., negative charge carriers) are present in a greater concentration than holes.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的两个选项（a）Hole和（b）Electron中选择一个正确答案，符合选择题的特征。 | 知识层次: 题目考查n型半导体中主要载流子的基本概念记忆，属于定义和分类层面的基础知识点。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别n型半导体的主要载流子类型（电子）。题目直接考察定义性知识，无需复杂理解或分析步骤，属于最简单的难度等级。", "convertible": true, "correct_option": "Electron", "choice_question": "For an n-type semiconductor, which type of charge carrier is present in the greater concentration?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly identifies the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Electron", "B": "Hole", "C": "Equal concentration of both", "D": "Depends on the doping concentration" }, "correct_answer": "A", "explanation": "In n-type semiconductors, electrons are the majority charge carriers due to donor doping. Option B exploits the common confusion between n-type and p-type semiconductors. Option C creates a false symmetry perception by suggesting equal concentrations. Option D introduces a conditional trap that seems plausible but ignores the fundamental definition of n-type materials where electrons always dominate regardless of doping level.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3418, "question": "Explain the meaning of the steel grade 00Cr18Ni10", "answer": "00Cr18Ni10 is an austenitic stainless steel, with Wc≤0.03%, WCr=18%, WNi=10%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释钢材牌号00Cr18Ni10的含义，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对不锈钢牌号命名规则的基本概念记忆和理解，需要解释牌号中各元素的含义及其含量范围，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目要求解释钢号00Cr18Ni10的含义，正确选项直接给出了该钢号的成分和分类（奥氏体不锈钢），属于基础概念记忆层次的知识点。选择题型中，学生只需识别并选择与记忆内容匹配的选项，无需进行复杂的概念分析或推理，因此难度较低。", "convertible": true, "correct_option": "00Cr18Ni10 is an austenitic stainless steel, with Wc≤0.03%, WCr=18%, WNi=10%", "choice_question": "Which of the following correctly describes the steel grade 00Cr18Ni10?", "conversion_reason": "The answer is a standard description of the steel grade, which can be converted into a multiple-choice question format by presenting it as the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "00Cr18Ni10 is an austenitic stainless steel, with Wc≤0.03%, WCr=18%, WNi=10%", "B": "00Cr18Ni10 is a ferritic stainless steel, with Wc≤0.03%, WCr=18%, WNi=10%", "C": "00Cr18Ni10 is an austenitic stainless steel, with Wc≤0.08%, WCr=18%, WNi=8%", "D": "00Cr18Ni10 is a duplex stainless steel, with Wc≤0.03%, WCr=18%, WNi=10%" }, "correct_answer": "A", "explanation": "The correct answer is A because 00Cr18Ni10 is indeed an austenitic stainless steel with the specified composition. Option B is incorrect by misclassifying it as ferritic, exploiting the common confusion between austenitic and ferritic stainless steels. Option C is incorrect by slightly altering the nickel content and increasing the carbon content, which could mislead based on similar steel grades. Option D is incorrect by classifying it as duplex, which is a common mistake when seeing balanced chromium and nickel content.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3288, "question": "What is martensite?", "answer": "The supersaturated solid solution formed by carbon in α-Fe is called martensite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"martensite\"进行定义解释，需要文字描述而非选择、判断或计算 | 知识层次: 题目考查基本概念的记忆和理解，即马氏体的定义，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察对马氏体基本定义的记忆，属于最基础的概念性知识。正确选项直接给出了马氏体的定义，不需要进行任何概念解释或复杂分析，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The supersaturated solid solution formed by carbon in α-Fe is called martensite.", "choice_question": "What is martensite?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct option and distractor options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The supersaturated solid solution formed by carbon in α-Fe", "B": "The equilibrium phase of carbon in γ-Fe at room temperature", "C": "A metastable phase formed by rapid cooling of austenite with high carbon content", "D": "The body-centered tetragonal crystal structure resulting from diffusionless transformation" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines martensite as a supersaturated solid solution of carbon in α-Fe. Option B is a cognitive bias trap, confusing martensite with pearlite which is the equilibrium phase. Option C is a professional intuition trap, describing the formation process but not the fundamental definition. Option D is a multi-level verification trap, correctly describing the crystal structure but missing the key aspect of carbon supersaturation in α-Fe.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4887, "question": "For a continuous and oriented fiber-reinforced composite, the moduli of elasticity in the longitudinal and transverse directions are 33.1 and 3.66 \\mathrm{GPa}\\left(4.8 × 10^{6}\\right. and \\left.5.3 × 10^{5} psi\\right), respectively. If the volume fraction of fibers is 0.30 , determine the moduli of elasticity of fiber and matrix phases.", "answer": "the moduli of elasticity of the matrix and fiber phases are: \\[\ne_{m} = 2.6 \\, \\text{gpa} (3.77 × 10^{5} \\, \\text{psi})\n\\] \\[\ne_{f} = 104 \\, \\text{gpa} (15 × 10^{6} \\, \\text{psi})\n\\]", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的复合材料纵向和横向弹性模量以及纤维体积分数，计算出纤维和基体相的弹性模量。这需要进行数值计算和公式应用，答案也是具体的数值结果。 | 知识层次: 题目需要应用复合材料弹性模量的计算公式，涉及纵向和横向弹性模量的关系，以及纤维和基体体积分数的考虑。虽然计算过程相对直接，但需要理解复合材料的力学行为和公式的适用条件，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解复合材料纵向和横向弹性模量的概念，并运用体积分数进行多步计算。虽然题目提供了正确选项，但解题过程涉及综合分析弹性模量的关系，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "the moduli of elasticity of the matrix and fiber phases are: e_m = 2.6 GPa (3.77 × 10^5 psi), e_f = 104 GPa (15 × 10^6 psi)", "choice_question": "For a continuous and oriented fiber-reinforced composite, the moduli of elasticity in the longitudinal and transverse directions are 33.1 and 3.66 GPa (4.8 × 10^6 and 5.3 × 10^5 psi), respectively. If the volume fraction of fibers is 0.30, what are the moduli of elasticity of the fiber and matrix phases?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "e_m = 2.6 GPa, e_f = 104 GPa", "B": "e_m = 3.77 GPa, e_f = 15 GPa", "C": "e_m = 5.3 GPa, e_f = 48 GPa", "D": "e_m = 0.53 GPa, e_f = 150 GPa" }, "correct_answer": "A", "explanation": "正确答案A通过混合法则和逆混合法则精确计算得出。干扰项B交换了矩阵和纤维的模量数值，利用单位psi与GPa的混淆。干扰项C直接使用了题目中横向模量的数值作为矩阵模量，是典型的直觉陷阱。干扰项D故意将psi单位数值当作GPa使用，同时夸大纤维模量，测试单位转换敏感性。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4725, "question": "For an ASTM grain size of 6, approximately how many grains would there be per square inch at a magnification of 100x?", "answer": "32 grains/in.^2", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过计算得出ASTM晶粒尺寸为6时，在100倍放大下每平方英寸的晶粒数量。解答需要应用ASTM晶粒尺寸计算公式，属于数值计算类问题。答案以具体数值形式给出，符合计算题的特征。 | 知识层次: 题目涉及基本的ASTM晶粒度计算公式应用，仅需直接套用公式进行简单计算即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用ASTM晶粒度的基本公式进行计算，无需额外的概念理解或复杂的解题步骤。属于单一公式直接计算的简单题目。", "convertible": true, "correct_option": "32 grains/in.^2", "choice_question": "For an ASTM grain size of 6, approximately how many grains would there be per square inch at a magnification of 100x?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "32 grains/in.^2", "B": "64 grains/in.^2", "C": "16 grains/in.^2", "D": "8 grains/in.^2" }, "correct_answer": "A", "explanation": "The correct answer is A (32 grains/in.^2) because ASTM grain size number (n) relates to the number of grains per square inch at 100x magnification (N) by the formula N=2^(n-1). For n=6, N=2^(6-1)=32. Option B (64) is a common mistake from misapplying the formula as 2^n. Option C (16) results from incorrectly subtracting 2 instead of 1 in the exponent. Option D (8) comes from a double subtraction error in the exponent calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4923, "question": "The magnetic flux density within a bar of some material is 0.630 tesla at an H field of 5 x 10^5 A/m. What type(s) of magnetism would you suggest is (are) being displayed by this material? Why?", "answer": "This material would display both diamagnetic and paramagnetic behavior. All materials are diamagnetic, and since χm is positive and on the order of 10^-3, there would also be a paramagnetic contribution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释材料显示的磁性类型及其原因，答案提供了详细的文字解释和论述，而非简单的选择、判断或计算。 | 知识层次: 题目要求根据给定的磁场强度和磁通密度判断材料的磁性类型，并解释原因。这需要理解磁性的基本概念（如抗磁性和顺磁性），并能将理论知识与给定的数据联系起来进行分析。虽然不涉及复杂的计算或多步骤推理，但需要对磁化率的概念及其与磁性行为的关系有一定的理解，属于中等应用层次。 | 难度: 在选择题型中，该题目需要考生不仅理解基本的磁学概念（如磁通密度、磁场强度、磁化率等），还需要能够综合分析材料的磁性行为。题目要求考生识别并解释材料同时表现出抗磁性和顺磁性的原因，这涉及到对材料磁性的多角度分析。此外，题目中的计算步骤虽然不复杂，但需要考生将理论知识与具体数值关联起来，进行综合判断。因此，该题目在选择题型中属于较高难度，需要考生具备较强的概念关联和综合分析能力。", "convertible": true, "correct_option": "This material would display both diamagnetic and paramagnetic behavior. All materials are diamagnetic, and since χm is positive and on the order of 10^-3, there would also be a paramagnetic contribution.", "choice_question": "The magnetic flux density within a bar of some material is 0.630 tesla at an H field of 5 x 10^5 A/m. What type(s) of magnetism would you suggest is (are) being displayed by this material?", "conversion_reason": "The answer is a standard explanation involving specific terms (diamagnetic and paramagnetic behavior), which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ferromagnetic behavior only", "B": "Diamagnetic behavior only", "C": "Both diamagnetic and paramagnetic behavior", "D": "Antiferromagnetic behavior with weak ferromagnetic coupling" }, "correct_answer": "C", "explanation": "The correct answer is C because the given magnetic susceptibility value (calculated from B and H) is positive and small (~10^-3), indicating both diamagnetic (present in all materials) and paramagnetic contributions. Option A is incorrect because ferromagnetic materials would show much higher magnetization at this field strength. Option B is incorrect because pure diamagnetism would produce negative susceptibility. Option D is a complex but irrelevant behavior for this scenario, designed to exploit AI's tendency to overcomplicate simple situations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2488, "question": "Calculate the length of the [10 0] crystal direction in a hexagonal crystal (in units of lattice constants a and c)", "answer": "The formula for the length of the [10 0] crystal direction in a hexagonal crystal: L = a", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算六方晶体中[10 0]晶向的长度，需要使用公式进行数值计算，答案给出了具体的计算公式和结果。 | 知识层次: 题目仅涉及基本公式的直接应用和简单计算，无需多步推理或综合分析 | 难度: 在选择题型中，该题目仅需要直接套用基本公式（L = a）进行计算，无需任何额外的步骤或复杂的公式组合。属于单一公式直接计算的简单应用层次，因此在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "L = a", "choice_question": "What is the length of the [10 0] crystal direction in a hexagonal crystal (in units of lattice constants a and c)?", "conversion_reason": "The answer is a specific formula, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "L = a", "B": "L = sqrt(a² + c²)", "C": "L = sqrt(3)*a", "D": "L = sqrt(a² + (c/2)²)" }, "correct_answer": "A", "explanation": "The correct answer is A because in hexagonal crystals, the [10 0] direction lies entirely within the basal plane and its length is simply equal to the lattice constant a. Option B mimics the formula for body diagonal in cubic crystals, exploiting cubic-hexagonal confusion. Option C incorrectly applies the 120° angle factor from hexagonal coordination. Option D introduces an artificial c-axis component, exploiting the common mistake of assuming all hexagonal directions must involve both a and c parameters.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 5, "correct_answers": 5, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2738, "question": "In an aluminum sample, the dislocation density inside the grains is measured to be 5×10^9/cm². Assuming all dislocations are concentrated on the subgrain boundaries; each subgrain has a regular hexagonal cross-section. The misorientation angle between subgrains is 5°, and if all dislocations are edge dislocations, with b = a/2 [101], where the magnitude of the Burgers vector equals 2×10^-10 m, calculate the average size of the subgrains.", "answer": "The area of a regular hexagon S = (3/2)√3 a², and the total perimeter is 6a. The number of subgrains per unit area n = 1/S. The dislocation density ρ = 5×10^13 = (1/S) × 6a × (1/D) × (1/2). Solving gives a = 1×10^-5 m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解亚晶的平均尺寸，涉及到了具体的数学运算和物理公式的应用。答案也展示了具体的计算过程和结果。 | 知识层次: 题目涉及多步计算和概念关联，包括位错密度、亚晶界、位错类型和Burgers矢量的综合应用。需要理解几何关系并进行公式推导和数值计算，但不需要复杂的机理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解位错密度、亚晶界、位错类型和伯格斯矢量等多个概念，并进行多步骤计算。虽然题目提供了正确选项的解题思路，但仍需要综合运用材料科学和几何知识来推导亚晶尺寸，涉及单位换算和公式变形等操作。", "convertible": true, "correct_option": "a = 1×10^-5 m", "choice_question": "In an aluminum sample, the dislocation density inside the grains is measured to be 5×10^9/cm². Assuming all dislocations are concentrated on the subgrain boundaries; each subgrain has a regular hexagonal cross-section. The misorientation angle between subgrains is 5°, and if all dislocations are edge dislocations, with b = a/2 [101], where the magnitude of the Burgers vector equals 2×10^-10 m, what is the average size of the subgrains?", "conversion_reason": "The original question is a calculation problem with a specific numerical answer. It can be converted into a multiple-choice question by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1×10^-5 m", "B": "2×10^-6 m", "C": "5×10^-7 m", "D": "1×10^-4 m" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the relationship between dislocation density, misorientation angle, and subgrain size. The key equation is θ = b/d, where θ is the misorientation angle (converted to radians), b is the Burgers vector magnitude, and d is the subgrain size. Option B is designed to trap those who forget to convert degrees to radians. Option C exploits a common error in handling dislocation density units (using m^-2 instead of cm^-2). Option D is a plausible but incorrect scaling based on misinterpreting the hexagonal geometry.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2605, "question": "In the periodic table, how do the properties of elements in the same main group change from top to bottom?", "answer": "From top to bottom, the ionization energy decreases, the ability to lose electrons increases, the ability to gain electrons decreases, the metallic character increases, and the non-metallic character decreases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对元素周期表中同一主族元素性质的变化进行文字解释和论述，答案提供了详细的描述而非选择或判断。 | 知识层次: 题目考查元素周期表中主族元素性质变化的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个元素性质的变化规律（如电离能、得失电子能力、金属性等），但这些都属于同一主族元素性质的基础概念记忆和简单描述。不需要进行复杂的比较分析或推导，只需理解并记忆主族元素从上到下的性质变化趋势即可。因此，在选择题型内属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "From top to bottom, the ionization energy decreases, the ability to lose electrons increases, the ability to gain electrons decreases, the metallic character increases, and the non-metallic character decreases.", "choice_question": "In the periodic table, how do the properties of elements in the same main group change from top to bottom?", "conversion_reason": "The answer is a standard description of the periodic trends in the main group elements, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ionization energy increases due to stronger nuclear shielding effects", "B": "The metallic character decreases as atomic orbitals become more diffuse", "C": "The electron affinity becomes more negative with increasing principal quantum number", "D": "The atomic radius decreases as additional electron shells are filled" }, "correct_answer": "A", "explanation": "The correct answer is A because ionization energy actually decreases from top to bottom in a group due to increasing atomic radius and electron shielding, despite the stronger nuclear charge. Option B is wrong because metallic character actually increases down a group. Option C is wrong because electron affinity generally becomes less negative (easier to gain electrons) down a group. Option D is wrong because atomic radius increases down a group as additional electron shells are added.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4881, "question": "What is the process of injection molding used to form plastic materials?", "answer": "For injection molding (normally used for thermoplastic materials), the raw materials are impelled by a ram through a heating chamber, and finally into the die cavity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释注射成型的过程，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查注射成型过程的基本概念和原理，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别注射成型的基本定义和流程，属于最基础的概念记忆层次。正确选项直接描述了注射成型的过程，没有涉及复杂概念或需要分析比较的内容，因此属于等级1的基本定义简答难度。", "convertible": true, "correct_option": "For injection molding (normally used for thermoplastic materials), the raw materials are impelled by a ram through a heating chamber, and finally into the die cavity.", "choice_question": "What is the process of injection molding used to form plastic materials?", "conversion_reason": "The answer is a standard description of the process, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The raw materials are impelled by a ram through a heating chamber, and finally into the die cavity", "B": "The plastic is first vulcanized under high pressure before being injected into the mold", "C": "A rotating screw both melts and conveys the material forward into the mold cavity", "D": "The material is extruded through a die to form continuous profiles before being cut to length" }, "correct_answer": "A", "explanation": "The correct answer describes the classic injection molding process for thermoplastics using a ram system. Option B introduces vulcanization (a rubber process) to confuse thermoplastic processing. Option C describes a modern screw-based system which is technically correct but not the classic ram-based process specified in the original question. Option D describes extrusion molding, a completely different process, exploiting visual similarity in equipment.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2095, "question": "At 800°C, what are the fractions of α phase and γ phase in Fe-0.002C steel?", "answer": "nα=0.58, nγ=0.42.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算在特定温度下Fe-0.002C钢中α相和γ相的比例，需要通过相图或相关公式进行数值计算，最终给出具体的数值结果。答案以数值形式呈现，符合计算题的特征。 | 知识层次: 题目需要应用相图知识进行多步计算，涉及相平衡的概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图的基本概念，能够正确识别800°C时Fe-0.002C钢所处的相区，并应用杠杆定律进行两相含量的计算。虽然题目给出了具体温度（800°C）和成分（0.002C），简化了相区判断的步骤，但仍需要进行多步计算和概念关联，包括：", "convertible": true, "correct_option": "nα=0.58, nγ=0.42", "choice_question": "At 800°C, what are the fractions of α phase and γ phase in Fe-0.002C steel?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "nα=0.58, nγ=0.42", "B": "nα=0.42, nγ=0.58", "C": "nα=0.72, nγ=0.28", "D": "nα=0.28, nγ=0.72" }, "correct_answer": "A", "explanation": "正确答案A基于铁碳相图在800°C下的杠杆定律计算得出。干扰项B通过颠倒α和γ相比例制造认知偏差；干扰项C利用常见的高温相占比增加的直觉错误；干扰项D则通过极端数值偏差诱导选择。所有干扰项都利用了材料科学中相变比例判断的常见误区。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3927, "question": "Is it possible to produce a polymer that is 100% crystalline? (a) True (b) False", "answer": "False. It is not possible to produce a polymer that is 100% crystalline. The maximum crystallinity that can be obtained is about 95%, with the remaining material being amorphous.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目以判断陈述对错的形式提问，要求选择True或False作为答案，符合判断题的特征。 | 知识层次: 题目考查对聚合物结晶度的基本概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目直接询问聚合物是否可以100%结晶，正确选项明确给出了基础定义和基本原理（聚合物最大结晶度约为95%）。这只需要学生对聚合物结晶度的基本概念有记忆性了解即可回答，无需深入理解或分析多个概念。因此属于选择题型中最基础的难度等级。", "convertible": true, "correct_option": "False. It is not possible to produce a polymer that is 100% crystalline. The maximum crystallinity that can be obtained is about 95%, with the remaining material being amorphous.", "choice_question": "Is it possible to produce a polymer that is 100% crystalline? (a) True (b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials are inherently brittle at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain advanced ceramics like transformation-toughened zirconia can exhibit significant toughness through stress-induced phase transformations. This statement is false because it uses the absolute term 'all' which doesn't account for these exceptions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2719, "question": "Derive the volume change rate ΔVa/Va due to lattice constant expansion when the temperature increases from T1 to T2.", "answer": "ΔVa/Va = (a + Δa)^3 - a^3 / a^3 = 3 × (Δa/a).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过公式推导和数值计算来求解体积变化率，答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目要求应用基本公式进行简单的体积变化率计算，涉及基本的代数运算和热膨胀概念的直接应用，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要理解体积变化率的概念，但解题步骤相对直接，仅需应用基本的体积变化公式并进行简单的代数运算。不需要多个公式的组合或复杂的分析过程，因此属于等级2难度。", "convertible": true, "correct_option": "3 × (Δa/a)", "choice_question": "What is the volume change rate ΔVa/Va due to lattice constant expansion when the temperature increases from T1 to T2?", "conversion_reason": "The answer is a specific mathematical expression, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3 × (Δa/a)", "B": "(Δa/a)^3", "C": "3 × α × (T2 - T1)", "D": "exp[3 × α × (T2 - T1)] - 1" }, "correct_answer": "A", "explanation": "The correct answer is A because the volume change rate for a cubic crystal is three times the linear expansion rate (Δa/a). Option B is a cognitive bias trap that incorrectly applies cubic expansion to linear terms. Option C uses the thermal expansion coefficient α but misses the direct relationship with lattice constant change. Option D is a multi-level verification trap that introduces an exponential form which only applies to certain non-linear thermal expansion scenarios.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3527, "question": "Explain the role of Mg element in aluminum alloys", "answer": "Magnesium has a good solid solution strengthening effect in aluminum, which can increase the strength of aluminum while also reducing its density. The precipitation strengthening effect of magnesium-aluminum alloys is not significant, but they exhibit good corrosion resistance and can be used as corrosion-resistant alloys. Magnesium cannot serve as the main additive element for high-strength aluminum alloys alone; it must be combined with other elements to fully utilize its effects.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释镁元素在铝合金中的作用，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释镁元素在铝合金中的作用，涉及固溶强化、沉淀强化、腐蚀抗力等多个概念的综合应用，需要理解镁元素与其他元素的协同效应，属于中等应用层次。 | 难度: 在选择题型中，该题目要求考生不仅理解镁在铝合金中的基本固溶强化作用，还需要综合分析其与其他元素的协同效应、对密度的影响、腐蚀性能以及在高强度铝合金中的应用限制。这涉及多角度分析论述，超出了简单的概念记忆或单一知识点应用，属于较高难度的选择题。", "convertible": true, "correct_option": "Magnesium has a good solid solution strengthening effect in aluminum, which can increase the strength of aluminum while also reducing its density. The precipitation strengthening effect of magnesium-aluminum alloys is not significant, but they exhibit good corrosion resistance and can be used as corrosion-resistant alloys. Magnesium cannot serve as the main additive element for high-strength aluminum alloys alone; it must be combined with other elements to fully utilize its effects.", "choice_question": "Which of the following best describes the role of Mg element in aluminum alloys?", "conversion_reason": "The answer is a detailed and specific explanation that can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best description of the role of Mg in aluminum alloys.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Mg primarily forms intermetallic compounds with Al, significantly increasing hardness but reducing ductility", "B": "Mg acts as a grain refiner in Al alloys, improving strength through Hall-Petch mechanism while maintaining corrosion resistance", "C": "Mg has a good solid solution strengthening effect in Al, increasing strength while reducing density, but requires other elements for high-strength alloys", "D": "Mg creates precipitation hardening in Al alloys through Mg2Si phases, making it the primary strengthening mechanism in 6xxx series alloys" }, "correct_answer": "C", "explanation": "The correct answer is C because it accurately describes Mg's solid solution strengthening effect and the need for synergistic elements. Option A is incorrect as Mg-Al intermetallics are not the primary strengthening mechanism. Option B misrepresents Mg's role - while it affects grain size, it's not a grain refiner. Option D is partially correct about Mg2Si but misleadingly presents it as Mg's primary role, which is a common confusion in alloy design.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3368, "question": "What elements are commonly used to improve hardenability?", "answer": "Cr, Ni, Mn, Si, B", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举常见的元素来改善淬透性，答案是一系列元素符号，属于需要列举或简要回答的简答题类型 | 知识层次: 题目考查对常见合金元素及其作用的记忆，属于基础概念的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，此题属于基础概念记忆的简单题目。只需记住常见的提高淬透性元素（Cr, Ni, Mn, Si, B）即可作答，不需要进行概念解释或复杂分析。题目仅考察对基本元素的记忆，属于最基础的选择题难度等级。", "convertible": true, "correct_option": "Cr, Ni, Mn, Si, B", "choice_question": "Which of the following elements are commonly used to improve hardenability?", "conversion_reason": "The answer is a standard set of elements, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cr, Ni, Mn, Si, B", "B": "Cr, Ni, Mn, Si, C", "C": "Cr, Ni, Mo, Si, B", "D": "Cr, Ni, Mn, Al, B" }, "correct_answer": "A", "explanation": "正确答案A包含了所有已知能显著提高淬透性的合金元素。干扰项B用碳(C)替代硼(B)，利用了碳是钢中基本元素这一认知偏差。干扰项C用钼(Mo)替代锰(Mn)，利用了钼也是常用合金元素的直觉陷阱。干扰项D用铝(Al)替代硅(Si)，设计了需要区分相似元素作用的验证陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 553, "question": "3. The three crystal zones of an ingot refer to (8), (9), and (10).", "answer": "(8) surface fine grain zone; (9) columnar crystal zone; (10) central equiaxed coarse grain zone", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的晶体区域名称，需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查对铸锭三个晶区的基本概念的记忆，属于定义和分类的记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆和识别铸锭的三个晶区名称，属于基础概念记忆的简单题目。不需要解释或分析，只需直接回忆并匹配正确选项即可。", "convertible": true, "correct_option": "surface fine grain zone; columnar crystal zone; central equiaxed coarse grain zone", "choice_question": "The three crystal zones of an ingot refer to:", "conversion_reason": "The answer is a standard set of terms that can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "surface fine grain zone; columnar crystal zone; central equiaxed coarse grain zone", "B": "elastic zone; plastic zone; fracture zone", "C": "dendritic zone; equiaxed zone; single crystal zone", "D": "amorphous layer; transition layer; crystalline core" }, "correct_answer": "A", "explanation": "The correct answer A describes the three characteristic zones formed during solidification of an ingot: the fine-grained surface zone due to rapid cooling, columnar crystals growing perpendicular to the mold walls, and equiaxed crystals in the center. Option B incorrectly applies mechanical deformation zones to solidification structure. Option C mixes valid crystal growth terms but omits the critical surface zone. Option D describes a thin film deposition structure rather than bulk casting microstructure, exploiting the 'layer' terminology confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1886, "question": "When a small amount of CaO is doped into ThO2, write the corresponding solid solution formula (10)", "answer": "10) Th1-xCa2xO2", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求写出相应的固溶体化学式，需要根据掺杂规则进行推导并给出具体的化学式，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求根据掺杂情况写出固溶体化学式，需要理解掺杂原理和电荷平衡的概念，并进行多步推理和计算（如确定掺杂比例和电荷补偿方式），属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解掺杂固溶体的基本概念，掌握电荷平衡的计算方法，并能正确写出固溶体的化学式。虽然题目涉及多步计算和概念关联，但在选择题型中，通过选项可以辅助判断，降低了部分难度。", "convertible": true, "correct_option": "Th1-xCa2xO2", "choice_question": "When a small amount of CaO is doped into ThO2, what is the corresponding solid solution formula?", "conversion_reason": "The answer is a standard chemical formula, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Th1-xCaxO2", "B": "Th1-xCa2xO2", "C": "Th1-2xCaxO2", "D": "Th1-x/2CaxO2" }, "correct_answer": "B", "explanation": "The correct answer is B because when CaO (with Ca2+) is doped into ThO2 (with Th4+), charge neutrality requires two Ca2+ ions to substitute for one Th4+ ion, leading to the formula Th1-xCa2xO2. Option A is a common mistake where the charge balance is ignored. Option C incorrectly assumes a 1:1 substitution ratio. Option D creates a misleading fractional coefficient that seems plausible but violates stoichiometry rules.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3730, "question": "A ceramic matrix composite contains internal flaws as large as 0.001 cm in length. The plane strain fracture toughness of the composite is 45 MPa / m and the tensile strength is 550 MPa. Will the flaw cause the composite to fail before the tensile strength is reached? Assume that f=1.", "answer": "the applied stress required for the crack to cause failure is 11,354 MPa. the tensile strength of the composite is 550 MPa. any failure of the ceramic should be expected due to the massive overload, not because of the presence of the flaws.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算（计算裂纹导致失效所需的应力），并应用断裂力学公式（K_IC = f * σ * sqrt(πa)）。答案给出了具体的计算结果和比较过程，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括应用断裂力学公式计算临界应力，并将结果与材料的拉伸强度进行比较。虽然计算过程相对直接，但需要理解断裂韧性和裂纹尺寸之间的关系，以及如何应用这些概念来预测材料的失效行为。这超出了简单应用的范围，但尚未达到复杂分析或高级综合的层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及平面应变断裂韧性和拉伸强度的计算，需要应用断裂力学公式（K_IC = fσ√(πa)）来计算临界应力，然后将结果与给定的拉伸强度进行比较。虽然计算步骤明确，但需要综合应用多个概念并进行数值比较，属于多步骤计算和概念关联的综合分析问题。", "convertible": true, "correct_option": "the applied stress required for the crack to cause failure is 11,354 MPa. the tensile strength of the composite is 550 MPa. any failure of the ceramic should be expected due to the massive overload, not because of the presence of the flaws.", "choice_question": "A ceramic matrix composite contains internal flaws as large as 0.001 cm in length. The plane strain fracture toughness of the composite is 45 MPa / m and the tensile strength is 550 MPa. Will the flaw cause the composite to fail before the tensile strength is reached? Assume that f=1.", "conversion_reason": "The original question is a calculation problem with a definitive answer that can be presented as a correct option in a multiple-choice format. The answer explains the reasoning behind the failure mechanism, making it suitable for conversion into a multiple-choice question where the correct option is the detailed explanation provided.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, failure will occur due to tensile overload before the flaw becomes critical", "B": "Yes, the flaw will propagate catastrophically at 80% of the tensile strength", "C": "Yes, but only under cyclic loading conditions due to fatigue crack growth", "D": "No, because the flaw size is below the critical threshold for this material system" }, "correct_answer": "A", "explanation": "The correct answer is A because calculation shows the stress required for flaw propagation (11,354 MPa) far exceeds the tensile strength (550 MPa). B is a cognitive bias trap - the 80% value seems plausible but is numerically incorrect. C exploits fatigue intuition that doesn't apply to static loading. D plays on the common misconception about 'critical flaw size' without considering the actual fracture mechanics calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3860, "question": "A steel contains 18 % pearlite and 82 % primary ferrite at room temperature. Estimate the carbon content of the steel.", "answer": "the carbon content of the steel is 0.156 %c.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过计算来估计钢的碳含量，答案是一个具体的数值（0.156 %c），这表明解答过程涉及数值计算和公式应用。 | 知识层次: 题目需要进行多步计算和概念关联，涉及铁碳相图的应用和成分估算，需要综合分析珠光体和初生铁素体的比例来确定碳含量。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图中珠光体和初生铁素体的组成比例与碳含量的关系，并进行多步计算来估算碳含量。虽然题目给出了明确的比例关系，但仍需要考生具备综合分析能力和对相图的理解才能正确解答。", "convertible": true, "correct_option": "0.156 %c", "choice_question": "A steel contains 18 % pearlite and 82 % primary ferrite at room temperature. The carbon content of the steel is approximately:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.156 %c", "B": "0.77 %c", "C": "0.45 %c", "D": "0.0218 %c" }, "correct_answer": "A", "explanation": "The correct answer is A (0.156 %c) because pearlite forms from austenite containing 0.77% carbon, and the lever rule can be applied to the iron-carbon phase diagram to calculate the overall carbon content based on the given percentages of pearlite and primary ferrite. Option B (0.77 %c) is a trap for those who mistakenly assume the steel is entirely pearlite. Option C (0.45 %c) exploits the common eutectoid composition misconception. Option D (0.0218 %c) targets those who confuse the maximum solubility of carbon in ferrite with the overall composition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3284, "question": "Methods for controlling austenite grain size", "answer": "Methods for controlling austenite grain size: a) Establish appropriate heating specifications, including controlling heating temperature and holding time, rapid short-term heating; b) Control carbon content within a certain range and add a certain amount of alloying elements that hinder austenite grain growth, such as: Al, V, Ti, Zr, Nb, etc.; c) Consider the influence of the original microstructure, such as lamellar pearlite being more prone to coarsening than spheroidized pearlite during heating.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释控制奥氏体晶粒尺寸的方法，答案提供了详细的文字解释和论述，没有选项或计算要求，符合简答题的特征。 | 知识层次: 题目要求解释控制奥氏体晶粒尺寸的方法，涉及加热规范、合金元素添加和原始组织影响等多个方面的知识。需要综合理解和应用材料科学中的基本原理，并进行一定的分析和关联，但不需要过于复杂的推理或创新设计。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及控制奥氏体晶粒尺寸的多种方法，包括加热规范、碳含量和合金元素的影响以及原始组织的影响。虽然不需要复杂的计算，但需要对材料科学中的相关概念有较深的理解，并能综合分析不同因素对奥氏体晶粒尺寸的影响。", "convertible": true, "correct_option": "a) Establish appropriate heating specifications, including controlling heating temperature and holding time, rapid short-term heating; b) Control carbon content within a certain range and add a certain amount of alloying elements that hinder austenite grain growth, such as: Al, V, Ti, Zr, Nb, etc.; c) Consider the influence of the original microstructure, such as lamellar pearlite being more prone to coarsening than spheroidized pearlite during heating.", "choice_question": "Which of the following are methods for controlling austenite grain size?", "conversion_reason": "The answer provided is a detailed and structured list of methods, which can be converted into a multiple-choice question format by presenting these methods as options and asking the examinee to select the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Establish appropriate heating specifications, including controlling heating temperature and holding time, rapid short-term heating", "B": "Use cryogenic treatment to refine the grain structure through phase transformation", "C": "Apply high-frequency electromagnetic fields to disrupt grain boundary migration", "D": "Introduce nano-sized precipitates to pin grain boundaries during recrystallization" }, "correct_answer": "A", "explanation": "Correct answer A involves standard metallurgical practices for austenite grain control. Option B exploits confusion between martensitic transformation (cryogenic) and austenitic grain growth. Option C uses a plausible-sounding but non-standard method (electromagnetic fields are not used for austenite grain control). Option D is a sophisticated trap - while grain boundary pinning works for recrystallization, it's ineffective for austenite grain growth at high temperatures where precipitates dissolve.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4798, "question": "An aircraft component is fabricated from an aluminum alloy that has a plane strain fracture toughness of 40 MPa sqrt(m) (36.4 ksi sqrt(in)). It has been determined that fracture results at a stress of 300 MPa (43,500 psi) when the maximum (or critical) internal crack length is 4.0mm (0.16 in.). For this same component and alloy, will fracture occur at a stress level of 260 MPa (38,000 psi) when the maximum internal crack length is 6.0mm (0.24 in.)? Why or why not?", "answer": "fracture will occur since the value 42.4 MPa sqrt(m) is greater than the fracture toughness K_IC of the material, 40 MPa sqrt(m).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过公式计算临界应力强度因子，并与材料的断裂韧性进行比较，从而判断是否会发生断裂。解答过程涉及数值计算和公式应用。 | 知识层次: 题目需要应用断裂力学中的应力强度因子公式进行多步计算，并结合材料的断裂韧性进行综合分析判断。虽然计算过程相对直接，但需要理解公式中各参数的含义及其相互关系，并进行适当的数值计算和比较。 | 难度: 在选择题中属于中等难度，需要理解断裂韧性和临界应力强度因子的概念，并进行多步计算（包括应力强度因子的公式应用和比较分析）。虽然题目提供了部分参数，但需要考生综合运用这些参数来判断是否会发生断裂，涉及概念关联和综合分析能力。", "convertible": true, "correct_option": "fracture will occur since the value 42.4 MPa sqrt(m) is greater than the fracture toughness K_IC of the material, 40 MPa sqrt(m)", "choice_question": "An aircraft component is fabricated from an aluminum alloy that has a plane strain fracture toughness of 40 MPa sqrt(m) (36.4 ksi sqrt(in)). It has been determined that fracture results at a stress of 300 MPa (43,500 psi) when the maximum (or critical) internal crack length is 4.0mm (0.16 in.). For this same component and alloy, will fracture occur at a stress level of 260 MPa (38,000 psi) when the maximum internal crack length is 6.0mm (0.24 in.)? Why or why not?", "conversion_reason": "The question can be converted into a multiple-choice format because it has a definitive answer that can be presented as a correct option among possible choices. The original question is already in a form that can be directly used as the stem of a multiple-choice question, and the provided answer can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fracture will occur because the stress intensity factor (42.4 MPa√m) exceeds the material's fracture toughness", "B": "No fracture will occur because the applied stress (260 MPa) is below the original fracture stress (300 MPa)", "C": "No fracture will occur because the crack length increase is compensated by the stress reduction", "D": "Fracture will occur only if the component is subjected to cyclic loading conditions" }, "correct_answer": "A", "explanation": "The correct answer is A because the stress intensity factor K = σ√(πa) = 260√(π×0.003) = 42.4 MPa√m exceeds the material's fracture toughness (40 MPa√m). Option B is incorrect because it ignores the crack length effect on fracture. Option C is a common misconception about stress-crack length compensation. Option D introduces an irrelevant cyclic loading condition that doesn't apply to this static fracture analysis.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3191, "question": "Given: the melting point of aluminum Tm=993K, the volumetric heat of fusion Lm=1.836×10^9 J/m^3, the solid-liquid interface specific surface energy σ=93 mJ/m^2, and the atomic volume V0=1.66×10^-29 m^3. Considering the solidification of liquid aluminum at 1 atm, when the undercooling ΔT=19℃, calculate the critical nucleus size r*.", "answer": "The critical nucleus size r* = (2σ Tm) / (Lm ΔT) = (2 × 93 × 10^-3 × 993) / (1.836 × 10^9 × 19) = 9.45 × 10^-8 m = 94.5 nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和数据进行数值计算，最终得出一个具体的数值结果（临界核尺寸r*），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及多个参数的关联和综合分析，包括临界核尺寸的计算公式应用和单位转换，需要一定的理解和应用能力。 | 难度: 在选择题中属于中等偏上难度，需要理解临界核尺寸的概念，掌握相关公式，并进行多步计算。题目涉及多个物理量的代入和单位换算，要求考生具备一定的综合分析能力和计算准确性。虽然题目提供了所有必要参数，但计算过程较为复杂，需要仔细处理指数运算和单位转换。", "convertible": true, "correct_option": "94.5 nm", "choice_question": "Given the melting point of aluminum Tm=993K, the volumetric heat of fusion Lm=1.836×10^9 J/m^3, the solid-liquid interface specific surface energy σ=93 mJ/m^2, and the atomic volume V0=1.66×10^-29 m^3. Considering the solidification of liquid aluminum at 1 atm, when the undercooling ΔT=19℃, what is the critical nucleus size r*?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "94.5 nm", "B": "47.2 nm", "C": "189 nm", "D": "63.1 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (94.5 nm) calculated using the critical nucleus radius formula r* = 2σTm/(LmΔT). Option B (47.2 nm) is half the correct value, exploiting the common mistake of omitting the factor of 2 in the numerator. Option C (189 nm) doubles the correct answer, targeting those who might confuse the radius with diameter. Option D (63.1 nm) is derived by incorrectly using the atomic volume V0 instead of the volumetric heat of fusion Lm in the calculation, appealing to those who might confuse nucleation parameters.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2533, "question": "Briefly describe the law of solid solubility of specific group elements in the Hume-Rothery rules", "answer": "The solid solubility of solute elements from groups 11B to VB in solvent elements of group IB is the same (θ/a=1.36), regardless of the specific element types.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述Hume-Rothery规则中特定族元素的固溶度定律，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对Hume-Rothery规则中特定组元素固溶度定律的基本概念记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生描述Hume-Rothery规则中特定族元素固溶度的定律，属于概念解释和描述的层次。虽然涉及一定的记忆性知识，但不需要复杂的分析或比较多个概念，因此属于中等难度。", "convertible": true, "correct_option": "The solid solubility of solute elements from groups 11B to VB in solvent elements of group IB is the same (θ/a=1.36), regardless of the specific element types.", "choice_question": "Which of the following describes the law of solid solubility of specific group elements in the Hume-Rothery rules?", "conversion_reason": "The answer is a standard and specific description that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The solid solubility of solute elements from groups 11B to VB in solvent elements of group IB is the same (θ/a=1.36), regardless of the specific element types", "B": "Elements with similar atomic radii show complete solid solubility when their electronegativity difference is less than 0.4", "C": "The maximum solid solubility occurs when the valence electron concentration reaches 1.36 for all transition metal alloys", "D": "Group IB elements can dissolve up to 15 at.% of any element from groups 11B to VB due to their identical crystal structures" }, "correct_answer": "A", "explanation": "The correct answer A precisely states the specific group element solubility law in Hume-Rothery rules. Option B combines two correct but unrelated Hume-Rothery conditions (size factor and electronegativity) to create a plausible but incorrect rule. Option C misapplies the electron concentration rule (which is system-specific) as a universal value. Option D introduces a common misconception by mixing the group solubility rule with an arbitrary percentage limit and incorrect structural assumption.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3328, "question": "What are the types of quenching methods", "answer": "The quenching methods include: 1. Single-liquid quenching; 2. Dual-liquid quenching; 3. Graded quenching; 4. Isothermal quenching.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举淬火方法的类型，答案以文字解释和论述的形式给出，没有选项或计算要求 | 知识层次: 题目考查淬火方法的基本分类和记忆，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆淬火方法的分类，属于基础概念记忆的简单题目。正确选项直接列出了四种淬火方法，无需进一步解释或分析，符合等级1的基本定义简答要求。", "convertible": true, "correct_option": "Single-liquid quenching; Dual-liquid quenching; Graded quenching; Isothermal quenching", "choice_question": "Which of the following are the types of quenching methods?", "conversion_reason": "The answer provided is a list of standard terms or concepts, which can be converted into a multiple-choice question format by presenting these terms as options and asking the examinee to select the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Single-liquid quenching", "B": "Martempering (martensite tempering)", "C": "Graded quenching", "D": "Austenitizing" }, "correct_answer": "A", "explanation": "The correct answer is A because single-liquid quenching is a fundamental quenching method where the material is rapidly cooled in a single medium. Option B is a cognitive bias trap - while 'martempering' sounds related to quenching, it's actually a specific heat treatment process, not a quenching method. Option C is a valid quenching method but is included here to test if the AI can distinguish between primary and secondary methods. Option D exploits professional intuition by using a pre-quenching heat treatment term that novices might confuse with quenching itself.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4140, "question": "At the Curie temperature, the saturation magnetization abruptly diminishes. Which of the following magnetic material types will have Curie temperatures?(a) Diamagnetics(b) Paramagnetics(c) Ferromagnetics(d) Antiferromagnetics(e) Ferrimagnetics", "answer": "Ferromagnetic and ferrimagnetic materials will have Curie temperatures.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且答案明确指出了正确选项 | 知识层次: 题目考查对磁性材料基本分类和特性的记忆，特别是关于居里温度与不同类型磁性材料的关系。只需要记住哪些材料具有居里温度即可回答，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（Curie温度的定义和适用材料类型），但需要学生能够区分不同磁性材料的特性，特别是Ferromagnetic和Ferrimagnetic材料的共同点。这要求一定的概念理解和简单辨析能力，而不仅仅是直接记忆。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "(c) Ferromagnetics, (e) Ferrimagnetics", "choice_question": "At the Curie temperature, the saturation magnetization abruptly diminishes. Which of the following magnetic material types will have Curie temperatures?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer specifies which options are correct. It can be converted to a single-choice format by selecting the correct options as the answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress for slip in FCC metals decreases with increasing temperature", "B": "The Peierls-Nabarro stress for dislocation motion in BCC metals is temperature independent", "C": "The Hall-Petch coefficient for nanocrystalline materials increases with grain size refinement", "D": "The stacking fault energy in HCP metals determines their deformation twinning propensity" }, "correct_answer": "D", "explanation": "Correct answer is D because stacking fault energy directly influences the ease of deformation twinning in HCP metals. Option A is a cognitive bias trap - while CRSS generally decreases with temperature, the relationship is not linear and depends on the specific material. Option B exploits professional intuition - Peierls-Nabarro stress in BCC metals actually shows strong temperature dependence due to screw dislocation core structure. Option C is a multi-level verification trap - while grain size affects strength, the Hall-Petch coefficient itself is a material constant.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4677, "question": "High-density polyethylene may be chlorinated by inducing the random substitution of chlorine atoms for hydrogen. In what ways does this chlorinated polyethylene differ from poly(vinyl chloride)?", "answer": "chlorinated polyethylene differs from poly(vinyl chloride) in that, for pvc, (1) 25% of the side-bonding sites are substituted with Cl, and (2) the substitution is probably much less random.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来比较两种材料的差异，答案提供了详细的文字说明而非选择、判断或计算。 | 知识层次: 题目要求比较两种高分子材料的差异，涉及对材料结构和性能的理解，需要综合分析氯原子取代方式和随机性对材料性质的影响，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，需要考生进行多角度分析和论述。题目不仅要求理解高密度聚乙烯氯化与聚氯乙烯在氯原子取代方面的差异，还需要比较两种材料在取代位置（25% vs 随机）和取代规律性（非随机 vs 随机）的具体区别。这涉及到对高分子材料结构改性的深入理解，以及在不同条件下取代反应特性的综合分析。在选择题型内，这种需要同时掌握具体数据（25%）和反应机理（随机性）的题目较为复杂，属于等级4难度。", "convertible": true, "correct_option": "chlorinated polyethylene differs from poly(vinyl chloride) in that, for pvc, (1) 25% of the side-bonding sites are substituted with Cl, and (2) the substitution is probably much less random.", "choice_question": "In what ways does chlorinated polyethylene differ from poly(vinyl chloride)?", "conversion_reason": "The answer is a specific and standard description of the differences between the two materials, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chlorinated polyethylene has a more random chlorine distribution while PVC has ordered 1:3 chlorine substitution", "B": "Chlorinated polyethylene exhibits higher thermal stability due to its fully saturated carbon backbone", "C": "PVC contains chlorine in alternating monomer units while chlorinated polyethylene has random side-chain chlorination", "D": "The chlorination process creates crosslinks in polyethylene but maintains linear chains in PVC" }, "correct_answer": "A", "explanation": "The correct answer A highlights the key difference in chlorine distribution patterns. Option B is a thermal stability misconception trap - while saturation might suggest stability, the random chlorination actually decreases it. Option C exploits monomer-level confusion by suggesting alternating units which is incorrect for PVC. Option D is a processing fallacy, implying incorrect structural changes during chlorination.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3188, "question": "Direct observation of an aluminum specimen shows a dislocation density within the grains of ρ=5×10^13/m^2. If the angle between subgrains is 5°, estimate the average size of the subgrains (the lattice constant of aluminum is a=2.8×10^-10m).", "answer": "Assuming all dislocations are concentrated on the subgrain boundaries and each subgrain is a regular hexagon with side length a and area S. S=1/2×a×√3/2×a×6=3√3/2×a^2. The number of subgrains per unit area is n=1/S. Substituting the values of D and S gives 1/2×6a×1/2.28×10^-9×1/(3/2×√3×a^2)=5×10^13. Finally, a=1.01×10^-5m is obtained, so the average subgrain size d=2a=2.02×10^-5m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计亚晶粒的平均尺寸，答案中包含了具体的计算步骤和最终数值结果。 | 知识层次: 题目需要进行多步计算和概念关联，包括对位错密度、亚晶界角度和晶格常数的综合分析，以及几何形状的假设和计算。虽然不涉及复杂的机理解释或创新设计，但需要一定的综合分析能力和公式应用技巧。 | 难度: 在选择题中属于中等偏上难度，需要理解位错密度、亚晶界角度和亚晶尺寸之间的关联，并进行多步计算。题目涉及几何关系推导（六边形面积计算）、单位转换和代数运算，虽然正确选项提供了计算步骤，但需要较强的综合分析能力和材料科学基础知识才能正确理解和应用。", "convertible": true, "correct_option": "2.02×10^-5m", "choice_question": "Direct observation of an aluminum specimen shows a dislocation density within the grains of ρ=5×10^13/m^2. If the angle between subgrains is 5°, estimate the average size of the subgrains (the lattice constant of aluminum is a=2.8×10^-10m). The average subgrain size is:", "conversion_reason": "The problem is a calculation question with a specific numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.02×10^-5m", "B": "1.12×10^-6m", "C": "3.57×10^-4m", "D": "5.64×10^-7m" }, "correct_answer": "A", "explanation": "正确答案A通过Read-Shockley关系θ=b/D计算得出，其中θ=5°=0.087rad，b=a/√2=1.98×10^-10m，D=θ/ρb=0.087/(5×10^13×1.98×10^-10)=2.02×10^-5m。干扰项B错误地使用了晶格常数a代替伯格斯矢量b进行计算。干扰项C忽略了角度单位转换(直接使用5°而非弧度)。干扰项D错误地将位错密度ρ放在分子位置计算。这些干扰项利用了材料科学中常见的单位混淆和公式误用陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2467, "question": "What is the interdiffusion coefficient D for the A-B binary system at 550K with molar fractions x_A=0.6 and x_B=0.4, given D_B^AB=9×10^-12 cm²/s, D_A^AB=2×10^-12 cm²/s, and d²G/dx_B²=-95.325?", "answer": "The interdiffusion coefficient D is calculated as D = (x_A * D_B^AB + x_B * D_A^AB) * (x_A * x_B / (R * T)) * (d²G/dx_B²) = (0.6 * 2×10^-16 + 0.4 * 9×10^-16) * (0.6 * 0.4 / (8.314 * 550)) * (-95.325) m²/s = -2.4×10^-18 m²/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和数据进行数值计算，最终得出一个具体的数值结果。答案中包含了详细的公式应用和计算步骤，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括应用给定的公式和参数，涉及不同变量的综合运用和单位转换。虽然不涉及复杂的推理分析或机理解释，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于综合性计算问题，需要理解多个概念（如互扩散系数、摩尔分数、热力学参数等）并进行多步骤计算。虽然题目提供了所有必要参数，但计算过程涉及多个变量的组合和单位转换（如cm²/s到m²/s），要求考生具备较强的综合计算能力和概念关联能力。相比简单记忆或单步计算的选择题，这类题目在选择题型中属于较高难度。", "convertible": true, "correct_option": "-2.4×10^-18 m²/s", "choice_question": "What is the interdiffusion coefficient D for the A-B binary system at 550K with molar fractions x_A=0.6 and x_B=0.4, given D_B^AB=9×10^-12 cm²/s, D_A^AB=2×10^-12 cm²/s, and d²G/dx_B²=-95.325?", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, making it suitable for conversion into a multiple-choice format. The correct option can be directly derived from the provided solution.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-2.4×10^-18 m²/s", "B": "3.6×10^-12 cm²/s", "C": "1.8×10^-11 m²/s", "D": "-9.5×10^-13 cm²/s" }, "correct_answer": "A", "explanation": "正确答案A通过Darken方程计算得出：D = (x_A*D_B + x_B*D_A)*(1 + dlnγ/dlnx) = (0.6*9×10^-12 + 0.4*2×10^-12)*(-95.325/8.314/550) = -2.4×10^-18 m²/s。干扰项B使用了错误的单位转换且忽略了热力学因子，利用单位认知偏差。干扰项C直接相加扩散系数，利用简单算术直觉陷阱。干扰项D错误地将d²G/dx_B²值直接作为扩散系数，利用参数混淆策略。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2712, "question": "When the temperature increases from 20℃ to 1020℃, the lattice constant expands by (4 × 10^-4)%, and the density decreases by 0.012%. Assuming the total mass remains unchanged, calculate the total volume change rate ΔV/V.", "answer": "(1 + ΔV/V) × (1 - 0.00012) = 1 → ΔV/V ≈ 0.012%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，通过给定的条件计算体积变化率，答案也是通过计算得出的具体数值。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，需要理解密度和体积之间的关系，并进行直接套用公式计算体积变化率。虽然涉及温度变化和晶格常数，但计算过程相对直接，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然题目涉及了热膨胀和密度变化的概念，但解题过程仅需要直接套用给定的百分比变化关系（密度减少0.012%对应体积增加0.012%），并通过简单的代数运算得出结果。不需要复杂的推导或多步骤计算，因此属于等级2难度。", "convertible": true, "correct_option": "0.012%", "choice_question": "When the temperature increases from 20℃ to 1020℃, the lattice constant expands by (4 × 10^-4)%, and the density decreases by 0.012%. Assuming the total mass remains unchanged, the total volume change rate ΔV/V is approximately:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.012%", "B": "0.004%", "C": "0.016%", "D": "0.008%" }, "correct_answer": "A", "explanation": "The correct answer is A (0.012%) because the density decrease directly reflects the volume expansion when mass is constant (ρ=m/V). B (0.004%) is the linear expansion rate cubed (4×10^-4%)^3, tempting those who mistake lattice expansion for volumetric change. C (0.016%) adds lattice and density changes incorrectly, exploiting additive intuition. D (0.008%) averages the two values, a common heuristic trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4663, "question": "Beryllium (Be) has an HCP unit cell for which the ratio of the lattice parameters c/a is 1.568. If the radius of the Be atom is 0.1143 nm, determine the unit cell volume.", "answer": "4.87 × 10^{-23} cm3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（HCP晶胞参数与原子半径的关系）来确定晶胞体积，答案是一个具体的数值结果（4.87 × 10^{-23} cm3），符合计算题的特征。 | 知识层次: 题目需要多步计算和概念关联，包括HCP晶格参数与原子半径的关系、晶格参数c/a比的应用以及体积计算公式的综合运用。虽然不涉及复杂的推理分析或创新应用，但需要一定的综合分析能力来正确应用公式和计算步骤。 | 难度: 在选择题中属于中等偏上难度，需要理解HCP晶体结构的基本概念，掌握晶格参数与原子半径的关系，并进行多步计算。题目要求考生能够将c/a比与原子半径联系起来，推导出晶格参数a和c的具体数值，最后计算单位晶胞体积。虽然题目提供了部分参数，但解题过程涉及多个步骤和概念的综合运用，在选择题型中属于需要一定分析和计算能力的题目。", "convertible": true, "correct_option": "4.87 × 10^{-23} cm3", "choice_question": "Beryllium (Be) has an HCP unit cell for which the ratio of the lattice parameters c/a is 1.568. If the radius of the Be atom is 0.1143 nm, determine the unit cell volume.", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.87 × 10^{-23} cm3", "B": "3.92 × 10^{-23} cm3", "C": "5.64 × 10^{-23} cm3", "D": "4.12 × 10^{-23} cm3" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算HCP晶胞体积得到的。对于HCP结构，晶格参数a与原子半径r的关系为a=2r，因此a=0.2286 nm。根据给定的c/a比，c=1.568×0.2286=0.3584 nm。HCP晶胞体积V=√3a²c/2=4.87×10^{-23} cm3。干扰项B错误地使用了FCC结构的体积计算公式。干扰项C忽略了HCP结构的堆垛因子计算错误。干扰项D在单位换算时出现了错误，将nm³直接当作cm³使用。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 418, "question": "2. In polymer chains, the different spatial forms of molecules due to (4) are called conformations", "answer": "Internal rotation of single bonds", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释聚合物链中由于某种原因导致的不同空间形式，答案需要提供文字解释（Internal rotation of single bonds），而不是选择、判断或计算。 | 知识层次: 题目考查聚合物链中构象的基本概念，仅需记忆和理解由于单键内旋转导致分子不同空间形式的定义，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目直接考察对聚合物链构象形成原因的基础概念记忆，仅需识别\"Internal rotation of single bonds\"这一明确定义即可作答，无需进行概念解释或复杂分析。正确选项与题干关键词\"conformations\"存在直接对应关系，属于最基础的概念识别类选择题。", "convertible": true, "correct_option": "Internal rotation of single bonds", "choice_question": "In polymer chains, the different spatial forms of molecules due to (4) are called conformations. Which of the following is the correct reason?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Internal rotation of single bonds", "B": "Variation in monomer sequence distribution", "C": "Changes in crystallinity degree", "D": "Thermal vibration of side groups" }, "correct_answer": "A", "explanation": "The correct answer is A because polymer chain conformations specifically arise from the internal rotation around single bonds (σ bonds) along the polymer backbone, which allows different spatial arrangements without breaking chemical bonds. Option B exploits a common confusion between chain conformation and sequence distribution - while sequence affects overall properties, it doesn't cause conformational changes. Option C uses the important but irrelevant concept of crystallinity, which is a bulk property rather than molecular-level conformation. Option D creates a subtle trap by referencing real thermal motions (side group vibrations) that don't actually alter the main chain conformation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 188, "question": "At $20^{\\\\circ}\\\\mathrm{C}$ and normal pressure, mercury with a radius of $10~\\\\mathrm{^{-3}}\\\\mathrm{m}$ is dispersed into small mercury droplets with a radius of $10^{-9}\\\\mathrm{m}$. Calculate the work required for this process. The surface tension of mercury at $20^{\\\\circ}\\\\mathrm{C}$ is $0.47\\\\mathrm{N/m}$.", "answer": "The work required for this process should equal the increase in the system's surface energy, i.e., $\\\\[ \\\\overline{W} = \\\\frac{0.47 \\\\times 10^{-9}}{10^{-27}} \\\\times 4 \\\\times 3.14 \\\\times 10^{-18} = 59 \\\\, \\\\text{W} \\\\]$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算，涉及公式应用和具体数值的代入计算，答案也是具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括表面能的计算和液滴数量的估算，涉及概念关联和综合分析。虽然公式应用直接，但需要理解表面能与液滴半径变化的关系，并进行适当的单位转换和数值计算。 | 难度: 在选择题中属于中等偏上难度，需要理解表面能的概念，掌握表面张力与表面积变化的关系，并进行多步计算。题目涉及从宏观到微观的尺度转换，要求考生能够正确应用公式并处理数量级变化，属于综合性计算问题。", "convertible": true, "correct_option": "59 W", "choice_question": "At $20^{\\circ}\\mathrm{C}$ and normal pressure, mercury with a radius of $10~\\mathrm{^{-3}}\\mathrm{m}$ is dispersed into small mercury droplets with a radius of $10^{-9}\\mathrm{m}$. The surface tension of mercury at $20^{\\circ}\\mathrm{C}$ is $0.47\\mathrm{N/m}$. Calculate the work required for this process.", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format with the correct option being the calculated work required.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "59 W", "B": "5.9 kJ", "C": "0.47 J", "D": "470 mN/m" }, "correct_answer": "A", "explanation": "正确答案A是通过计算表面能变化得出的正确结果。干扰项B利用了单位换算陷阱，将焦耳错误转换为千焦。干扰项C直接使用了表面张力值而忽略计算过程。干扰项D混淆了表面张力单位与最终所需功的单位，是典型的单位陷阱设计。这些干扰项都利用了AI在处理单位转换和复杂计算时可能出现的直觉错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3501, "question": "What is the main difference between cast iron and carbon steel?", "answer": "The main difference between carbon steel and cast iron lies in the carbon content and the form of carbon present. The carbon content in cast iron is greater than 2.11%, while that in carbon steel is greater than 0.0218% but less than 2.11%. In carbon steel, apart from a portion dissolved in ferrite, all other carbon exists in the form of Fe3C. In cast iron, a small amount of carbon is dissolved in ferrite, while most of the carbon exists in the form of graphite (gray cast iron) or Fe3C (white cast iron). The microstructure is not entirely the same, leading to differences in properties (both processing and service performance).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释cast iron和carbon steel的主要区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查的是对碳钢和铸铁的基本区别的记忆和理解，主要涉及碳含量和碳的存在形式等基础概念，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解并区分两种材料（铸铁和碳钢）在碳含量和碳存在形式上的差异。正确选项提供了较为详细的解释，包括碳含量的具体范围、碳的存在形式（Fe3C或石墨）以及由此导致的性能差异。这要求考生不仅记住定义，还要能够理解和比较这些概念。因此，在选择题型内，该题目属于等级2（概念解释和描述）难度。", "convertible": true, "correct_option": "The main difference between carbon steel and cast iron lies in the carbon content and the form of carbon present. The carbon content in cast iron is greater than 2.11%, while that in carbon steel is greater than 0.0218% but less than 2.11%. In carbon steel, apart from a portion dissolved in ferrite, all other carbon exists in the form of Fe3C. In cast iron, a small amount of carbon is dissolved in ferrite, while most of the carbon exists in the form of graphite (gray cast iron) or Fe3C (white cast iron). The microstructure is not entirely the same, leading to differences in properties (both processing and service performance).", "choice_question": "What is the main difference between cast iron and carbon steel?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cast iron has higher thermal conductivity due to its graphite flakes acting as phonon scattering centers", "B": "Carbon steel exhibits better corrosion resistance because its microstructure forms a passive oxide layer", "C": "The key difference is in their carbon solubility limits: 0.77% for steel vs 4.3% for cast iron at eutectic temperature", "D": "Cast iron contains silicon as a mandatory alloying element while carbon steel does not" }, "correct_answer": "D", "explanation": "Correct answer D is subtle but accurate: silicon is essential in cast iron to promote graphite formation. Option A reverses the phonon scattering effect of graphite. Option B is incorrect as carbon steel lacks chromium for passive layers. Option C uses accurate solubility data but misrepresents them as the primary distinguishing feature.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1603, "question": "What is the difference in continuity between the two metal plastic deformation mechanisms of slip and twinning?", "answer": "The slip process can proceed continuously while the twinning process cannot proceed continuously.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两种金属塑性变形机制（滑移和孪生）在连续性方面的差异，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对金属塑性变形机制中滑移和孪生两种基本过程的理解和记忆，属于基础概念的记忆和简单对比。 | 难度: 该题目属于选择题型中的概念解释和描述难度等级。虽然题目涉及两种金属塑性变形机制（滑移和孪生）的比较，但正确选项仅要求考生区分两者的连续性差异这一特定概念特征，不需要进行复杂的体系阐述或多概念交叉分析。在选择题型中，这属于对基础概念的理解和简单应用，符合等级2\"概念解释和描述\"的难度特征。", "convertible": true, "correct_option": "The slip process can proceed continuously while the twinning process cannot proceed continuously.", "choice_question": "What is the difference in continuity between the two metal plastic deformation mechanisms of slip and twinning?", "conversion_reason": "The answer is a standard comparison between two mechanisms, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip occurs through discrete atomic plane shifts while twinning involves continuous lattice rotation", "B": "Both mechanisms proceed continuously but at different strain rate sensitivities", "C": "Twinning can proceed continuously while slip requires discrete dislocation movements", "D": "Slip process can proceed continuously while twinning cannot proceed continuously" }, "correct_answer": "D", "explanation": "The correct answer is D because slip involves continuous dislocation motion under stress, while twinning occurs in discrete, finite steps that reorient the crystal lattice. Option A reverses the continuity characteristics. Option B incorrectly states both are continuous. Option C inverts the correct relationship. These distractors exploit common misconceptions about deformation mechanisms and the intuitive but incorrect assumption that lattice rotation implies continuity.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 620, "question": "Jog and kink", "answer": "Jog and kink: During the movement of dislocations, certain dislocation intersection lines are formed after intersecting with other dislocations. If the dislocation line after intersection lies on the original slip plane of the dislocation, this dislocation line is called a kink. If the dislocation line after intersection is perpendicular to the original slip plane of the dislocation, this dislocation line is called a jog.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Jog and kink\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查对位错运动中形成的jog和kink的基本定义和分类的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并区分\"jog\"和\"kink\"这两个位错运动中的基本概念，需要掌握它们的定义和形成条件。虽然涉及两个相关概念，但每个概念的定义相对明确，不需要进行复杂的比较分析或推导。在选择题型中，这属于中等偏下的难度，主要考察对基础概念的记忆和理解能力。", "convertible": true, "correct_option": "Jog and kink: During the movement of dislocations, certain dislocation intersection lines are formed after intersecting with other dislocations. If the dislocation line after intersection lies on the original slip plane of the dislocation, this dislocation line is called a kink. If the dislocation line after intersection is perpendicular to the original slip plane of the dislocation, this dislocation line is called a jog.", "choice_question": "Which of the following correctly describes 'Jog and kink' in the context of dislocation movement?", "conversion_reason": "The original question is a short answer question that asks for a definition or explanation of 'Jog and kink'. This can be converted into a multiple-choice question by providing the correct definition as one of the options and asking the examinee to select the correct description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Jog and kink are formed when a dislocation intersects with another dislocation, with kink lying on the original slip plane and jog perpendicular to it", "B": "Jog and kink are temporary defects that disappear when dislocations move away from each other", "C": "Jog is a segment parallel to the Burgers vector while kink is perpendicular to it", "D": "Both jog and kink must lie on the same slip plane as the original dislocation" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the geometric relationship between jog/kink formations and the original slip plane. Option B exploits the cognitive bias that all dislocation interactions are temporary. Option C uses a plausible-sounding but incorrect definition based on Burgers vector orientation. Option D creates a verification trap by requiring the examinee to recognize that only kink remains on the original slip plane while jog does not.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4124, "question": "Do carbon-carbon composites exhibit high thermal conductivities?", "answer": "Carbon-carbon composites have high thermal conductivities.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个是非判断问题，要求判断\"碳碳复合材料是否具有高热导率\"这一陈述的正确性。答案直接给出了明确的判断结果(\"具有高热导率\")，符合判断题的特征。 | 知识层次: 题目考查对碳碳复合材料基本特性的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念正误判断，仅需记忆碳-碳复合材料的基本特性（高导热性）即可作答，无需理解或分析复杂概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "Carbon-carbon composites have high thermal conductivities.", "choice_question": "Do carbon-carbon composites exhibit high thermal conductivities?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All carbon-carbon composites exhibit higher thermal conductivity than copper at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While some carbon-carbon composites can have high thermal conductivity due to graphitic structure alignment, not all exceed copper's conductivity (≈400 W/m·K). The statement's absolute claim is incorrect as conductivity depends on fiber type, orientation, and processing conditions. Many C/C composites actually have lower conductivity than copper.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2437, "question": "For a face-centered cubic crystal stretched along the [131] axis, determine the resolved shear stress of the slip system (111)[10-1]. The tensile stress is 6.9×10^5 Pa", "answer": "For the slip system (111)[10-1], the cosine of the angle between [131] and the slip plane normal [111] is cosφ=5/(√3×√11)=0.870; the cosine of the angle between [131] and the slip direction [10-1] is cosλ=(1×1 + 3×0 + 1×(-1))/(√11×√(1+0+1))=0/(√11×√2)=0. The resolved shear stress τ=6.9×10^5×0.870×0 Pa=0 Pa", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定剪切应力，解答过程中涉及角度计算和应力分解，最终给出具体的数值结果。 | 知识层次: 题目需要多步计算和概念关联，包括计算角度余弦和应用分解剪应力公式，涉及晶体学方向和应力分解的综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体学方向指数、滑移系统、分解剪应力等概念，并进行多步向量计算（包括点积和模的计算）。虽然题目提供了具体数值，但考生仍需正确应用公式并执行准确的计算步骤，包括角度余弦值的确定和最终应力计算。这种综合性计算问题在选择题型中属于较高要求。", "convertible": true, "correct_option": "0 Pa", "choice_question": "For a face-centered cubic crystal stretched along the [131] axis, the resolved shear stress of the slip system (111)[10-1] under a tensile stress of 6.9×10^5 Pa is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0 Pa", "B": "2.8×10^5 Pa", "C": "4.1×10^5 Pa", "D": "5.7×10^5 Pa" }, "correct_answer": "A", "explanation": "The correct answer is 0 Pa because the slip direction [10-1] is perpendicular to the tensile axis [131], resulting in zero resolved shear stress. Option B (2.8×10^5 Pa) is designed to exploit the common mistake of not properly calculating the angle between the slip direction and tensile axis. Option C (4.1×10^5 Pa) is a cognitive bias trap that incorrectly assumes the maximum possible resolved shear stress. Option D (5.7×10^5 Pa) is a professional intuition trap that miscalculates the Schmid factor by using the wrong angle between the slip plane normal and tensile axis.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4159, "question": "Match the following material types with their light transmission characteristics: Porous electrical insulators - Transparent, Opaque, Translucent", "answer": "Porous electrical insulators are opaque to visible light.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项（Transparent, Opaque, Translucent）中选择与材料类型（Porous electrical insulators）匹配的光传输特性。 | 知识层次: 题目考查对材料光学特性分类的基础概念记忆，仅需将材料类型与透光性进行简单匹配，不涉及复杂推理或综合分析。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需识别和回忆材料的光学特性分类。题目直接给出了材料类型和其对应的光传输特性，无需进行复杂辨析或深度理解，属于最简单的概念识别类型。", "convertible": true, "correct_option": "Opaque", "choice_question": "What is the light transmission characteristic of porous electrical insulators?", "conversion_reason": "The original question is already in a multiple-choice format, and it can be directly converted to a single-choice question by specifying the correct option from the given choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Opaque", "B": "Transparent", "C": "Translucent", "D": "Variable depending on pore size" }, "correct_answer": "A", "explanation": "Porous electrical insulators are inherently opaque due to multiple light scattering at the numerous air-material interfaces. Option B exploits the cognitive bias that associates electrical insulators with optical transparency (like glass). Option C creates confusion with partially crystalline materials. Option D is a professional intuition trap, suggesting pore size affects transparency when in reality even nanoscale porosity causes opacity through Rayleigh scattering.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2604, "question": "In the periodic table, what are the differences in atomic structure of elements in the same period from left to right?", "answer": "From left to right, the nuclear charge increases sequentially, and the atomic radius gradually decreases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释元素在同一周期中从左到右的原子结构差异，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查元素周期表中同一周期元素原子结构变化的基本概念，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并比较同一周期内元素原子结构的变化趋势（核电荷增加和原子半径减小），而不仅仅是记忆单一的定义。这要求考生对周期表的基本规律有一定的理解和应用能力，但不需要复杂的分析或推理步骤。", "convertible": true, "correct_option": "From left to right, the nuclear charge increases sequentially, and the atomic radius gradually decreases.", "choice_question": "In the periodic table, what are the differences in atomic structure of elements in the same period from left to right?", "conversion_reason": "The answer is a standard description of the atomic structure differences in the periodic table, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Nuclear charge increases while electron shielding remains constant, leading to decreased atomic radius", "B": "Both nuclear charge and electron shielding increase proportionally, maintaining constant atomic radius", "C": "Nuclear charge increases but additional electron shells compensate, keeping atomic radius unchanged", "D": "Increasing nuclear charge is offset by greater electron-electron repulsion, resulting in larger atomic radius" }, "correct_answer": "A", "explanation": "The correct answer is A because within a period, electrons are added to the same principal energy level while protons are added to the nucleus. This increases effective nuclear charge without significant increase in shielding, causing atomic radius to decrease. Option B is wrong because electron shielding does not increase proportionally with nuclear charge in the same period. Option C is incorrect because no additional electron shells are added within a period. Option D is misleading because while electron-electron repulsion exists, it doesn't overcome the increased nuclear attraction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 372, "question": "Schottky defect", "answer": "A vacancy defect formed by displaced atoms migrating to the outer surface under thermal equilibrium conditions", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对Schottky defect进行文字解释和论述，答案提供了详细的定义和形成条件，符合简答题的特征 | 知识层次: 题目考查Schottky缺陷的基本定义和形成条件，属于基础概念的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对Schottky缺陷基本定义的记忆，属于最基础的概念性知识。正确选项直接描述了缺陷的形成机制，无需复杂分析或概念间的关联理解，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "A vacancy defect formed by displaced atoms migrating to the outer surface under thermal equilibrium conditions", "choice_question": "Which of the following best describes a Schottky defect?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A vacancy defect formed by displaced atoms migrating to the outer surface under thermal equilibrium conditions", "B": "An interstitial defect caused by high-energy particle bombardment creating Frenkel pairs", "C": "A charge-neutral defect complex consisting of cation vacancies and anion vacancies in equal numbers", "D": "A lattice distortion defect resulting from size mismatch between dopant and host atoms" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes a Schottky defect as a vacancy defect where atoms move to the surface. Option B incorrectly describes a Frenkel defect. Option C is partially correct but misleadingly emphasizes charge neutrality which is not the defining characteristic. Option D describes a completely different type of defect (size mismatch) to create a red herring for those who confuse defect types.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3015, "question": "The elasticity of a polymer is related to which temperature? A. $T_{\\\\mathrm{m}}$ B. $T_{_{8}}$ C. $T_{t}$ D.Ta", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对聚合物弹性相关温度的基本概念记忆，只需识别与弹性相关的温度符号即可，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即聚合物弹性与特定温度的关系。正确选项C（$T_{t}$）是直接记忆性知识点，无需复杂理解或辨析。因此，该题目属于简单概念识别，直接记忆的难度等级。", "convertible": true, "correct_option": "C", "choice_question": "The elasticity of a polymer is related to which temperature?", "conversion_reason": "The original question is already in a multiple-choice format, which can be directly used as a single-choice question. The correct option is provided as 'C'.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The temperature where storage modulus equals loss modulus (tan δ=1)", "B": "The onset temperature of rubbery plateau in DMA measurements", "C": "The temperature at which polymer chains achieve complete freedom of rotation", "D": "The midpoint temperature of glass transition measured by DSC" }, "correct_answer": "B", "explanation": "The correct answer is B because the onset of rubbery plateau directly indicates the transition from glassy to elastic behavior. Option A exploits the common misconception that tan δ peak corresponds to elasticity transition (actually indicates maximum energy dissipation). Option C uses an intuitive but incorrect definition of chain mobility. Option D leverages the cognitive bias toward DSC measurements while ignoring that Tg midpoint doesn't correlate with elastic properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1588, "question": "The microscopic mechanisms of diffusion in crystalline solids include (12)", "answer": "(12) interstitial mechanism", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释晶体固体中扩散的微观机制，答案以文字形式给出，需要简要描述扩散机制的类型。 | 知识层次: 题目考查晶体固体中扩散的微观机制，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别晶体固体中扩散的微观机制之一（间隙机制），属于基础概念记忆层次。题目仅涉及单一知识点的直接回忆，无需解释、比较或分析多个概念，因此属于选择题型中最简单的难度等级。", "convertible": true, "correct_option": "interstitial mechanism", "choice_question": "The microscopic mechanisms of diffusion in crystalline solids include:", "conversion_reason": "The answer is a standard term (interstitial mechanism), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial mechanism", "B": "Dislocation climb mechanism", "C": "Surface diffusion mechanism", "D": "Grain boundary sliding mechanism" }, "correct_answer": "A", "explanation": "The interstitial mechanism is the correct answer as it is a fundamental microscopic mechanism for diffusion in crystalline solids where atoms move through the interstitial spaces. Dislocation climb (B) is a creep mechanism, not a primary diffusion mechanism. Surface diffusion (C) occurs only at surfaces, not in bulk crystals. Grain boundary sliding (D) is a deformation mechanism in polycrystalline materials, unrelated to atomic diffusion within crystals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1508, "question": "What is the phenomenon called when a metal with finer grains exhibits higher strength and hardness but lower plasticity and toughness compared to the same metal with coarser grains?", "answer": "Grain refinement strengthening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释一个现象的名称，需要文字回答而非选择、判断或计算 | 知识层次: 题目考查对晶粒细化强化现象的基本概念记忆和理解，属于材料科学中的基础知识点。 | 难度: 在选择题中属于中等难度，需要理解晶粒细化强化的基本概念，并能够将其与金属的力学性能变化联系起来。虽然不涉及复杂的分析或比较，但需要一定的概念解释和描述能力。", "convertible": true, "correct_option": "Grain refinement strengthening", "choice_question": "What is the phenomenon called when a metal with finer grains exhibits higher strength and hardness but lower plasticity and toughness compared to the same metal with coarser grains?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain refinement strengthening", "B": "Hall-Petch effect", "C": "Solid solution strengthening", "D": "Precipitation hardening" }, "correct_answer": "A", "explanation": "The correct answer is A because grain refinement strengthening specifically describes the phenomenon where finer grains increase strength and hardness while reducing plasticity and toughness. Option B (Hall-Petch effect) is a strong distractor as it mathematically describes the grain size-strength relationship but doesn't encompass the full mechanical property trade-offs. Option C (solid solution strengthening) exploits confusion with another strengthening mechanism involving solute atoms. Option D (precipitation hardening) targets those who might associate hardness improvements with precipitate formation rather than grain boundaries.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1425, "question": "What is an extended dislocation? Please give an example.", "answer": "A dislocation configuration consisting of two partial dislocations and a stacking fault sandwiched between them. For example, in face-centered cubic crystals, $\\\\frac{a}{6}$ [121] $^+$ stacking fault $+{\\\\frac{a}{6}}$ [211].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释什么是扩展位错并给出一个例子，答案提供了详细的文字解释和具体实例，符合简答题的特征。 | 知识层次: 题目考查对扩展位错这一基本概念的定义记忆和简单理解，仅需描述其构成并举例说明，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目要求考生不仅记忆扩展位错的基本定义，还需要理解其具体构成（两个部分位错和中间的堆垛层错）并能举例说明（如面心立方晶体中的具体例子）。这超出了简单的定义记忆（等级1），但尚未达到需要阐述复杂概念体系的深度（等级3），因此属于概念解释和描述的中等难度（等级2）。", "convertible": true, "correct_option": "A dislocation configuration consisting of two partial dislocations and a stacking fault sandwiched between them. For example, in face-centered cubic crystals, $\\frac{a}{6}$ [121] $^+$ stacking fault $+{\\frac{a}{6}}$ [211].", "choice_question": "Which of the following best describes an extended dislocation?", "conversion_reason": "The answer is a standard definition and example of an extended dislocation, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A dislocation configuration consisting of two partial dislocations and a stacking fault sandwiched between them, e.g., in FCC crystals: $\frac{a}{6}$ [121] $^+$ stacking fault $+{\frac{a}{6}}$ [211]", "B": "A dislocation that has propagated beyond the crystal boundaries, creating long-range lattice distortions", "C": "A dislocation pair where the Burgers vectors sum to zero, forming a stable dipole configuration", "D": "A dislocation core that has undergone significant lattice diffusion, creating an extended defect region" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines an extended dislocation with the classic partial dislocation-stacking fault structure. Option B exploits the 'extended' literal interpretation trap. Option C describes a dislocation dipole, using a mathematically similar but physically distinct concept. Option D introduces diffusion effects, creating a plausible-sounding but incorrect advanced mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2724, "question": "Assume there is an edge dislocation with a b in the [0-10] direction gliding along the (100) crystal plane. If a screw dislocation with a b direction of [100] gliding on the (001) crystal plane passes through the aforementioned dislocation, will it form a kink or a jog?", "answer": "Jog", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从两个选项（kink或jog）中选择正确答案 | 知识层次: 题目需要理解位错的基本概念（如刃位错和螺位错的性质），并能够应用这些概念来分析两种位错相互作用的结果。虽然不涉及复杂的计算或多步推理，但需要对位错运动和相互作用有一定的综合分析能力。 | 难度: 在选择题型中，该题目属于复杂分析过程的判断难度。首先，题目涉及两种不同类型的位错（刃型位错和螺型位错）的相互作用，需要考生对位错的基本性质（如柏氏矢量和滑移面）有清晰的理解。其次，题目要求考生分析两种位错相互穿过时形成的缺陷类型（kink或jog），这需要综合应用位错理论中的相关知识，并进行空间想象和逻辑推理。此外，题目中的晶体学方向和平面描述增加了复杂性，要求考生能够准确地将抽象概念转化为具体情境。因此，该题目在选择题型内属于较高难度，需要考生具备较强的综合分析能力和概念应用能力。", "convertible": true, "correct_option": "Jog", "choice_question": "Assume there is an edge dislocation with a b in the [0-10] direction gliding along the (100) crystal plane. If a screw dislocation with a b direction of [100] gliding on the (001) crystal plane passes through the aforementioned dislocation, will it form a kink or a jog?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer, making it convertible to a single-choice question by presenting the options as choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Kink, because the dislocations are gliding on perpendicular planes", "B": "Jog, as the Burgers vectors are perpendicular to each other", "C": "Neither, since both dislocations are mobile and will simply pass through", "D": "Kink, due to the screw component of the edge dislocation" }, "correct_answer": "B", "explanation": "The correct answer is B because when a screw dislocation with b=[100] passes through an edge dislocation with b=[0-10], their Burgers vectors are perpendicular, creating a jog (non-conservative motion) in the edge dislocation line. Option A is a cognitive bias trap, as perpendicular glide planes don't necessarily mean kink formation. Option C exploits the common misconception that mobile dislocations always pass through unaffected. Option D creates confusion by suggesting the edge dislocation has a screw component, which it doesn't in this case.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1456, "question": "After metal undergoes cold plastic deformation, this phenomenon is called (42) strengthening or (43)", "answer": "deformation; work hardening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个专业术语（deformation; work hardening），属于需要文字回答的简答题类型，而非选择题、判断题或计算题。 | 知识层次: 题目考查金属冷塑性变形后的强化现象的基本概念记忆，即变形强化和加工硬化的术语填空，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目仅要求考生记忆并填写金属冷塑性变形后的两个专业术语（变形强化和加工硬化），属于基础概念记忆层次，无需复杂推理或概念体系阐述。选择题型中此类直接考查定义和术语的题目通常是最简单的类型。", "convertible": true, "correct_option": "work hardening", "choice_question": "After metal undergoes cold plastic deformation, this phenomenon is called deformation strengthening or:", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "work hardening", "B": "strain hardening", "C": "dislocation strengthening", "D": "precipitation hardening" }, "correct_answer": "A", "explanation": "The correct answer is A (work hardening) because it is the most widely accepted term for the phenomenon where metal becomes stronger after cold plastic deformation. B (strain hardening) is a strong distractor as it is a valid alternative term, but less commonly used in standard materials science terminology. C (dislocation strengthening) exploits the AI's tendency to focus on the underlying mechanism (dislocation multiplication), but this term refers to a specific type of strengthening rather than the general phenomenon. D (precipitation hardening) is a completely different strengthening mechanism that occurs in alloys through heat treatment, designed to catch AI models that might confuse different strengthening mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 215, "question": "Many properties of clay are related to the types of adsorbed cations. Indicate the variation pattern of the casting time of clay slurry when adsorbing the following different cations (use arrows to represent: small—large) H+ Al3+ Ba2+ Sr2+ Ca2+ Mg2+ NH4+ K+ Na+ Li+", "answer": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求用箭头表示不同阳离子吸附时粘土浆料浇注时间的变化规律，需要根据材料科学知识进行排序和解释，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求考生理解不同阳离子对粘土浆料浇注时间的影响，并能够根据离子特性（如离子半径、电荷数等）进行排序。这需要考生掌握粘土吸附阳离子的基本原理，并能将这些原理应用到具体情境中进行分析和判断。虽然不涉及复杂的计算或深度机理分析，但需要考生对多个概念进行关联和综合运用。 | 难度: 在选择题型中，该题目需要考生掌握粘土吸附不同阳离子时对浇铸时间的影响规律，涉及多个阳离子的比较和排序。考生需要理解阳离子的电荷、半径等性质对粘土性能的影响，并进行综合分析。虽然题目给出了正确选项，但需要考生具备较强的概念关联和综合分析能力，属于较高难度的选择题。", "convertible": true, "correct_option": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "choice_question": "Which of the following correctly represents the variation pattern of the casting time of clay slurry when adsorbing the cations H+, Al3+, Ba2+, Sr2+, Ca2+, Mg2+, NH4+, K+, Na+, Li+?", "conversion_reason": "The original question asks for a specific ordering of cations based on their effect on the casting time of clay slurry, which can be presented as a multiple-choice question with one correct sequence.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "B": "Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+ < H+", "C": "Al3+ < H+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "D": "H+ < Al3+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < NH4+ < K+ < Na+ < Li+" }, "correct_answer": "A", "explanation": "The correct answer A follows the actual variation pattern where casting time increases with decreasing cation valence and increasing hydrated radius. Option B reverses the entire sequence, exploiting the common misconception that smaller ionic radius always leads to faster casting. Option C incorrectly places Al3+ before H+, targeting confusion about the exceptional behavior of H+ in clay systems. Option D disrupts the divalent cation order (Mg2+ before Ca2+), capitalizing on the subtle hydration energy differences that even experts may misremember.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1614, "question": "Interstitial solid solution", "answer": "When the solute atoms are relatively small, they can enter the interstitial sites of the solvent lattice, and the solid solution formed in this way is called an interstitial solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Interstitial solid solution\"进行文字解释和论述，答案提供了详细的定义和形成机制，符合简答题的特征。 | 知识层次: 题目考查对间隙固溶体这一基本概念的定义和形成条件的记忆和理解，属于材料科学中最基础的概念性知识。 | 难度: 在选择题型中，该题目仅考察对\"interstitial solid solution\"基本定义的记忆，不需要解释或分析多个概念。正确选项直接给出了定义，属于最基础的概念记忆层次，因此难度等级为1。", "convertible": true, "correct_option": "When the solute atoms are relatively small, they can enter the interstitial sites of the solvent lattice, and the solid solution formed in this way is called an interstitial solid solution.", "choice_question": "Which of the following best describes an interstitial solid solution?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When the solute atoms are relatively small, they can enter the interstitial sites of the solvent lattice", "B": "When solute atoms replace solvent atoms in the crystal lattice while maintaining the same crystal structure", "C": "When solute atoms form a separate phase within the solvent matrix due to size mismatch", "D": "When solute atoms create lattice distortions large enough to form new crystallographic planes" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines interstitial solid solutions where small solute atoms occupy the spaces between solvent atoms. Option B describes substitutional solid solutions, a common confusion. Option C describes precipitation or phase separation, exploiting the 'size mismatch' intuition. Option D creates a trap by suggesting extreme lattice distortion that would actually form a new phase rather than a solid solution.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2362, "question": "Is the glass transition temperature of rubber band polymers above or below room temperature?", "answer": "The glass transition temperature of rubber band polymers is below room temperature. This is because rubber band polymers exhibit significant elasticity at room temperature; if they were in a glassy state at room temperature, they would not display elasticity but rather brittleness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释橡胶带聚合物的玻璃化转变温度与室温的关系，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对玻璃转变温度这一基本概念的记忆和理解，以及其在橡胶带聚合物中的具体表现。虽然需要一定的解释，但主要依赖于对基础概念的掌握，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接考察对玻璃化转变温度这一基础概念的记忆和理解，只需判断橡胶带聚合物在室温下的状态即可得出正确答案。不需要复杂的分析或概念间的联系，属于最基础的选择题难度等级。", "convertible": true, "correct_option": "below room temperature", "choice_question": "Is the glass transition temperature of rubber band polymers above or below room temperature?", "conversion_reason": "The answer is a standard term that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit the multiple-choice format by providing options such as 'above room temperature' and 'below room temperature'.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Below room temperature (Tg ≈ -70°C)", "B": "Above room temperature (Tg ≈ 120°C)", "C": "Exactly at room temperature (Tg = 25°C)", "D": "Depends on crosslink density (Tg range -50°C to 150°C)" }, "correct_answer": "A", "explanation": "Correct answer is A because natural rubber (polyisoprene) has Tg around -70°C, allowing elastic behavior at room temperature. B exploits confusion with vulcanization temperature. C traps those assuming perfect ambient adaptation. D misleads by suggesting crosslinks dominate Tg when they primarily affect elastic modulus.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4123, "question": "Do carbon-carbon composites exhibit large fracture toughness values?", "answer": "Carbon-carbon composites have large fracture toughness values.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个是非判断问题，要求判断\"碳碳复合材料是否具有大的断裂韧性值\"，答案直接给出了对错判断。这符合判断题的特征。 | 知识层次: 题目考查对碳碳复合材料基本性能的记忆和理解，属于基础概念层次。 | 难度: 该题目属于基础概念记忆层次，仅需判断碳碳复合材料是否具有较大的断裂韧性值这一基本事实。正确选项直接陈述了定义性知识，无需复杂理解或分析过程，在选择题型中属于最简单的正误判断级别。", "convertible": true, "correct_option": "Carbon-carbon composites have large fracture toughness values.", "choice_question": "Do carbon-carbon composites exhibit large fracture toughness values?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All carbon-carbon composites exhibit fracture toughness values above 30 MPa·m^1/2 due to their fiber reinforcement architecture.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While carbon-carbon composites generally have good fracture toughness, the absolute claim of 'all' exceeding 30 MPa·m^1/2 is incorrect. Actual values depend on fiber type, orientation, matrix properties, and processing conditions. Some architectures may fall below this threshold, making this an overgeneralization that catches those unfamiliar with the material's property range.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3107, "question": "Below the critical temperature Tc, superconductors exhibit complete (2) what property?", "answer": "Diamagnetism", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字回答超导体在临界温度以下表现出的特定性质，答案\"Diamagnetism\"是一个术语而非选项，需要学生对概念的理解和表述。 | 知识层次: 题目考查超导体在临界温度以下表现出的基本性质（完全抗磁性）的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需考生回忆超导体的基本特性之一——完全抗磁性（Diamagnetism）。题目直接考查定义性知识，无需解释或分析，解题步骤简单，属于最基础难度等级。", "convertible": true, "correct_option": "Diamagnetism", "choice_question": "Below the critical temperature Tc, superconductors exhibit complete (2) what property?", "conversion_reason": "The answer is a standard term (Diamagnetism), which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diamagnetism", "B": "Ferromagnetism", "C": "Paramagnetism", "D": "Zero electrical resistance" }, "correct_answer": "A", "explanation": "The correct answer is A (Diamagnetism) because superconductors below Tc exhibit the Meissner effect, which is perfect diamagnetism. Option B (Ferromagnetism) is incorrect but plausible because it involves strong magnetic properties. Option C (Paramagnetism) is incorrect but may seem right as it's a common magnetic response. Option D (Zero electrical resistance) is incorrect but highly tempting as it's the most famous property of superconductors, though the question specifically asks about magnetic properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2090, "question": "At 800°C, what are the compositions of the α phase and γ phase in Fe-0.002C steel?", "answer": "α: wC=0.0001, wFe=0.9999; γ: wC=0.0046, wFe=0.9954.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求计算在特定温度下α相和γ相的成分，需要参考相图或相关公式进行数值计算，答案给出了具体的数值结果。 | 知识层次: 题目需要应用铁碳相图的基本知识，通过查图和简单计算确定α相和γ相的成分。虽然涉及相图的理解，但计算过程直接，属于基本公式应用和简单计算的范畴。 | 难度: 在选择题型中，该题目属于简单应用层次，需要考生根据给定的温度（800°C）和钢的成分（Fe-0.002C），直接套用铁碳相图的基本知识来确定α相和γ相的成分。虽然涉及相图的应用，但题目已经提供了具体的温度点，且选项直接给出了计算结果，减少了复杂推导的需求。因此，该题目在选择题型内属于等级2难度，即简单公式应用计算。", "convertible": true, "correct_option": "α: wC=0.0001, wFe=0.9999; γ: wC=0.0046, wFe=0.9954", "choice_question": "At 800°C, what are the compositions of the α phase and γ phase in Fe-0.002C steel?", "conversion_reason": "The answer is a specific set of values, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "α: wC=0.0001, wFe=0.9999; γ: wC=0.0046, wFe=0.9954", "B": "α: wC=0.002, wFe=0.998; γ: wC=0.002, wFe=0.998", "C": "α: wC=0.0046, wFe=0.9954; γ: wC=0.0001, wFe=0.9999", "D": "α: wC=0.0001, wFe=0.9999; γ: wC=0.022, wFe=0.978" }, "correct_answer": "A", "explanation": "正确答案A基于铁碳相图在800°C时的相平衡数据。B选项错误地假设了均匀成分，忽略了相分离现象。C选项颠倒了α和γ相的成分，是典型的相混淆陷阱。D选项的γ相成分错误地采用了共析温度(727°C)下的溶解度数据，属于温度条件混淆陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1482, "question": "At 727°C, the maximum carbon content in the equilibrium iron-carbon alloy is w_C=0.0218% for ferrite, while the carbon content in austenite is w_C=0.77%. Explain why the carbon content differs so greatly between the two.", "answer": "Because the radius of the flat octahedral interstitial sites in the ferrite crystal is much smaller than that of the regular octahedral interstitial sites in the austenite crystal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释两种晶体结构中碳含量差异的原因，需要文字解释和论述，而不是选择、判断或计算。答案提供了详细的晶体结构差异解释，符合简答题的特征。 | 知识层次: 题目要求解释铁素体和奥氏体中碳含量差异的原因，涉及晶体结构中间隙位置的差异及其对碳溶解度的影响。这需要深入理解晶体结构、间隙固溶体以及相变等概念，并进行综合分析。思维过程需要从微观结构特征推导宏观性质差异，属于复杂分析和机理解释的范畴。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生理解并比较铁素体和奥氏体晶体结构中碳溶解度的差异，并解释其根本原因。正确选项涉及晶体结构中间隙位置的几何特征（平面八面体间隙与规则八面体间隙的半径差异），这需要考生具备：", "convertible": true, "correct_option": "Because the radius of the flat octahedral interstitial sites in the ferrite crystal is much smaller than that of the regular octahedral interstitial sites in the austenite crystal.", "choice_question": "At 727°C, the maximum carbon content in the equilibrium iron-carbon alloy is w_C=0.0218% for ferrite, while the carbon content in austenite is w_C=0.77%. Why does the carbon content differ so greatly between the two?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because the radius of the flat octahedral interstitial sites in the ferrite crystal is much smaller than that of the regular octahedral interstitial sites in the austenite crystal", "B": "Because the higher stacking fault energy of austenite allows more carbon atoms to be accommodated in its crystal structure", "C": "Because ferrite has a higher diffusion coefficient for carbon at this temperature, causing carbon to preferentially leave the phase", "D": "Because the magnetic ordering in ferrite creates electronic repulsion that limits carbon solubility" }, "correct_answer": "A", "explanation": "The correct answer is A because the BCC structure of ferrite has smaller and more distorted interstitial sites compared to the FCC structure of austenite. Option B is misleading because stacking fault energy is unrelated to interstitial solubility. Option C exploits the common misconception about diffusion rates affecting equilibrium solubility limits. Option D creates a false connection between magnetic properties and interstitial solubility that doesn't exist at this temperature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3109, "question": "Resistance materials can be divided into (1), (2), and (3) according to their characteristics and applications.", "answer": "(1) Precision resistance materials; (2) Film resistance materials; (3) Electric heating materials", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的分类名称，需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查对电阻材料分类的基本概念记忆，属于定义和分类的基础知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目要求考生记忆并识别电阻材料的分类，属于基础概念的记忆性知识。正确选项直接对应题目中的空缺部分，无需复杂推理或分析，仅需对电阻材料的基本分类有清晰记忆即可作答。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Precision resistance materials; Film resistance materials; Electric heating materials", "choice_question": "Resistance materials can be divided into which of the following according to their characteristics and applications?", "conversion_reason": "The original short answer question asks for a standard classification of resistance materials, which can be rephrased into a multiple-choice format by listing the correct classification as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Precision resistance materials", "B": "Structural resistance materials", "C": "Film resistance materials", "D": "Electric heating materials" }, "correct_answer": "A", "explanation": "Precision resistance materials are correct as they are specifically designed for stable resistance values. 'Structural resistance materials' is a cognitive bias trap - while structural materials may have resistance properties, they are not classified as resistance materials. Film resistance materials and electric heating materials are both valid classifications but are designed to test if the AI can distinguish between primary classifications (precision) and secondary applications (film/electric heating).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 31, "question": "In CaS, the unit cell parameter a=0.567 nm, and the anions and cations are in contact with each other. Calculate the radius of Ca2+. The radius of S2- is known to be 0.177 nm.", "answer": "In CaS, a=0.567 nm, and the anions and cations are in contact with each other, a=2(r+ + r-), therefore rCa2+=(0.567 nm / 2) - 0.177 nm = 0.107 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算，应用给定的公式（a=2(r+ + r-)）来求解Ca2+的半径，答案是一个具体的数值结果。 | 知识层次: 题目涉及基本的公式应用和简单计算，只需要直接套用已知的半径公式进行计算即可，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（a=2(r+ + r-)）进行简单计算即可得出答案，无需额外的概念理解或步骤组合。属于最基础的直接计算类型。", "convertible": true, "correct_option": "0.107 nm", "choice_question": "In CaS, the unit cell parameter a=0.567 nm, and the anions and cations are in contact with each other. The radius of S2- is known to be 0.177 nm. What is the radius of Ca2+?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.107 nm", "B": "0.142 nm", "C": "0.213 nm", "D": "0.284 nm" }, "correct_answer": "A", "explanation": "In a rocksalt structure like CaS, the body diagonal of the unit cell contains alternating anions and cations in contact. The sum of their ionic radii equals a√2/4. Given a=0.567 nm and r(S2-)=0.177 nm, solving for r(Ca2+) yields 0.107 nm. Distractors exploit common errors: B assumes simple cubic packing (a/2), C mistakenly uses a√3/4 (face diagonal), and D doubles the correct value, appealing to intuitive but incorrect scaling.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 798, "question": "In a simple cubic crystal, if the direction of the dislocation line is [112] and the Burgers vector is $b=a$ [110], determine the type of this dislocation.", "answer": "Since the direction of the dislocation line is perpendicular to the direction of the Burgers vector, this dislocation is an edge dislocation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来确定位错的类型，答案是一个简短的文字解释，而非选择、判断或计算。 | 知识层次: 题目需要理解位错线方向与伯格斯矢量的关系，并判断位错类型，涉及概念关联和综合分析，但不需要复杂的推理或机理解释。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握晶体中位错的基本概念，包括位错线的方向和Burgers向量的关系，并能判断位错的类型（刃位错或螺位错）。解题步骤涉及向量点积的计算和位错类型的判断，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "Since the direction of the dislocation line is perpendicular to the direction of the Burgers vector, this dislocation is an edge dislocation.", "choice_question": "In a simple cubic crystal, if the direction of the dislocation line is [112] and the Burgers vector is $b=a$ [110], what type of dislocation is this?", "conversion_reason": "The answer is a standard term or concept (edge dislocation), which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Edge dislocation (dislocation line ⊥ Burgers vector)", "B": "Screw dislocation (dislocation line ∥ Burgers vector)", "C": "Mixed dislocation (angle between vectors is 60°)", "D": "Partial dislocation (Burgers vector magnitude < a)" }, "correct_answer": "A", "explanation": "The correct answer is A because the dot product of [112] and [110] is zero, confirming perpendicularity. Option B exploits the common misconception that any non-perpendicular angle implies screw character. Option C uses the 60° angle which is typical for FCC crystals but irrelevant here. Option D introduces the unrelated concept of partial dislocations to distract from the core geometric relationship.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1965, "question": "When bending a tin plate (with a melting point of 232°C) back and forth at room temperature, what phenomenon will occur as the bending proceeds? Why?", "answer": "According to T_recrystallization=(0.35～0.45)Tm, the processing of Sn at room temperature is considered hot working. Therefore, as bending proceeds, dynamic recrystallization occurs in the Sn plate, allowing it to be bent for an extended period.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释现象并论述原因，答案提供了详细的文字解释和理论依据，符合简答题的特征。 | 知识层次: 题目需要综合运用动态再结晶理论（T_recrystallization=(0.35～0.45)Tm）和热加工概念，分析室温下锡板弯曲过程中的现象。这涉及材料科学中的相变机理、温度对材料行为的影响等复杂概念，并要求进行推理分析来解释现象。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Dynamic recrystallization occurs in the Sn plate, allowing it to be bent for an extended period.", "choice_question": "When bending a tin plate (with a melting point of 232°C) back and forth at room temperature, what phenomenon will occur as the bending proceeds?", "conversion_reason": "The answer is a standard scientific phenomenon (dynamic recrystallization) which can be presented as a correct option among plausible distractors in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dynamic recrystallization occurs in the Sn plate, allowing it to be bent for an extended period", "B": "Dislocation pile-up leads to rapid work hardening and fracture after few cycles", "C": "Localized melting occurs at grain boundaries due to frictional heating", "D": "Phase transformation from β-Sn to α-Sn occurs at the bending zone" }, "correct_answer": "A", "explanation": "The correct answer is A because tin exhibits dynamic recrystallization at room temperature (which is 0.6 of its melting point in Kelvin), allowing continuous deformation without fracture. Option B exploits the common intuition that metals should work-harden, but ignores tin's unique low-temperature recrystallization behavior. Option C uses the tempting but physically impossible scenario of room-temperature melting. Option D leverages the real α-β transition in tin, but falsely applies it to room-temperature deformation (the transition occurs at 13°C).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 511, "question": "Equilibrium distribution coefficient", "answer": "Equilibrium distribution coefficient: The ratio of the solute concentration in the solid phase to that in the liquid phase during equilibrium solidification.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对“Equilibrium distribution coefficient”进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查的是平衡分配系数的定义，属于基础概念的记忆和理解，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目仅要求记忆并识别平衡分配系数的基本定义，属于基础概念记忆层次。题目直接给出了定义，无需进行额外的解释或复杂分析，因此属于最简单的难度等级。", "convertible": true, "correct_option": "The ratio of the solute concentration in the solid phase to that in the liquid phase during equilibrium solidification.", "choice_question": "What is the definition of the equilibrium distribution coefficient?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ratio of the solute concentration in the solid phase to that in the liquid phase during equilibrium solidification", "B": "The ratio of the diffusion coefficients of solute atoms in solid and liquid phases at equilibrium", "C": "The ratio of the solidification front velocity to the solute diffusion velocity in the liquid phase", "D": "The ratio of the solute solubility limits in solid and liquid phases at a given temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because the equilibrium distribution coefficient is fundamentally defined as the ratio of solute concentrations in solid to liquid phases during equilibrium solidification. Option B exploits confusion with diffusion kinetics by using diffusion coefficients instead of concentrations. Option C creates a velocity-based trap that might appeal to models familiar with solidification dynamics. Option D uses solubility limits which is a related but distinct concept, exploiting the common confusion between distribution coefficient and solubility ratio.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2976, "question": "The difference between cast iron and carbon steel lies in the presence or absence of (A) ledeburite (B) pearlite (C) ferrite", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（A、B、C）中选择正确答案 | 知识层次: 题目考查对铸铁和碳钢的基本组成相的记忆，特别是莱氏体的存在与否这一基础概念，属于材料科学中基础知识的记忆和理解。 | 难度: 在选择题中属于中等偏下难度，需要理解铸铁和碳钢的基本区别，并能够识别莱氏体（ledeburite）的存在与否是关键差异点。虽然涉及基础概念记忆，但需要一定的材料学知识来区分不同组织的特征，属于概念理解和简单辨析的范畴。", "convertible": true, "correct_option": "A", "choice_question": "The difference between cast iron and carbon steel lies in the presence or absence of", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical cooling rate for martensite formation", "B": "The presence of substitutional alloying elements", "C": "The eutectoid reaction temperature", "D": "The stacking fault energy of austenite" }, "correct_answer": "A", "explanation": "The correct answer is A because the fundamental difference between cast iron and carbon steel lies in their carbon content and cooling behavior, where cast iron's higher carbon content allows ledeburite formation (eutectic) while steel forms pearlite (eutectoid). Option B exploits the common misconception that alloying elements are the key difference. Option C targets confusion between eutectic and eutectoid systems. Option D uses an advanced but irrelevant concept (stacking fault energy) to mislead those overcomplicating the analysis.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3321, "question": "Indicate the main purpose of normalizing T12 steel file and the structure after normalizing", "answer": "T12 steel file: Normalizing eliminates the network carbide and prepares for spheroidizing annealing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释T12钢文件的主要正火目的及正火后的结构，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释T12钢正火的主要目的及正火后的组织，涉及对正火工艺的理解和应用，需要将材料科学中的热处理知识与具体材料（T12钢）的特性相结合，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解T12钢正火的主要目的和后续球化退火的关系，涉及多个概念的综合分析。虽然题目给出了正确选项，但需要考生具备对正火工艺和球化退火的基本理解，以及对碳化物网络消除的认知。这种题目在选择题型中属于需要一定知识深度和概念关联的题目，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Normalizing eliminates the network carbide and prepares for spheroidizing annealing.", "choice_question": "What is the main purpose of normalizing T12 steel file and the structure after normalizing?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the main purpose and structure after normalizing.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Normalizing eliminates the network carbide and prepares for spheroidizing annealing", "B": "Normalizing refines the grain size to improve toughness while maintaining hardness", "C": "Normalizing dissolves all carbides to create a fully austenitic structure", "D": "Normalizing reduces internal stresses while preserving the original pearlite structure" }, "correct_answer": "A", "explanation": { "correct_answer": "For T12 hypereutectoid steel, normalizing specifically targets the elimination of continuous carbide networks at grain boundaries, which is crucial before spheroidizing annealing. This is a specialized treatment for high-carbon steels.", "distractors": { "B": "While grain refinement is a general benefit of normalizing, this option misrepresents the primary purpose for T12 steel by overemphasizing toughness improvement, which is less critical for this tool steel application.", "C": "This is incorrect because normalizing cannot dissolve all carbides in hypereutectoid steel - it's thermodynamically impossible at normalizing temperatures below the A1 line.", "D": "This option confuses the purpose of stress relief annealing with normalizing, and incorrectly states that original pearlite would be preserved in T12 steel after normalizing." }, "cognitive_traps": { "general_knowledge_trap": "Options B and D exploit general knowledge about normalizing that doesn't apply specifically to hypereutectoid steels.", "thermodynamic_trap": "Option C uses plausible-sounding metallurgical terms but violates phase diagram fundamentals.", "process_confusion": "Option D deliberately mixes up normalizing with stress relief annealing processes." } }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1695, "question": "How do different types of bonding affect the hardness of crystalline materials?", "answer": "The hardness of crystalline materials is closely related to the type of bonding. Crystals bonded by covalent, ionic, and metallic bonds generally exhibit higher hardness than those bonded by molecular bonds.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释不同键合类型对晶体材料硬度的影响，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目要求分析不同类型键合对晶体材料硬度的影响，需要理解不同键合类型的基本特性，并将这些特性与硬度这一宏观性能关联起来。这涉及到多概念的综合应用和中等程度的分析，但不需要复杂的机理推导或创新性设计。 | 难度: 在选择题中属于中等难度，需要理解不同化学键类型（共价键、离子键、金属键和分子键）对晶体硬度的影响，并进行概念关联和比较分析。题目要求考生综合运用材料科学基础知识，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "The hardness of crystalline materials is closely related to the type of bonding. Crystals bonded by covalent, ionic, and metallic bonds generally exhibit higher hardness than those bonded by molecular bonds.", "choice_question": "How does the type of bonding affect the hardness of crystalline materials?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Covalent bonding generally leads to the highest hardness due to directional electron sharing and strong bond energies", "B": "Ionic bonding produces the hardest materials because electrostatic forces are stronger than covalent bonds", "C": "Metallic bonding creates the hardest crystals as delocalized electrons provide uniform strength in all directions", "D": "Molecular bonding can achieve comparable hardness to covalent solids when hydrogen bonds are present" }, "correct_answer": "A", "explanation": "Correct answer A is justified because covalent bonds involve directional electron sharing with high bond energies, leading to high hardness (e.g., diamond). Option B is a cognitive bias trap - while ionic bonds are strong, they're not directional and materials are often brittle. Option C exploits metallic bonding misconceptions - while metals can be strong, hardness is generally lower than covalent materials. Option D is a molecular bonding overestimation - even with hydrogen bonds, molecular crystals can't match covalent solids' hardness.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1067, "question": "Given that copper has an FCC structure with an atomic radius of $0.1278\\\\mathrm{nm}$, calculate its density. (The atomic weight of copper is 63.5, and the Avogadro constant is $0.602\\\\times10^{24}$)", "answer": "Given that the Cu lattice has an FCC structure, meaning the unit cell contains 4 atoms, to find its density ρ, we only need to calculate the ratio of the mass of the atoms in the unit cell to the volume of the unit cell: $$\\\\rho={\\\\frac{n M}{N_{A}(2{\\\\sqrt{2}}r)^{3}}}={\\\\frac{4\\\\times63.5\\\\times10^{-3}}{0.602\\\\times10^{24}\\\\times(2{\\\\sqrt{2}}\\\\times0.1278\\\\times10^{-9})^{3}}}\\\\mathrm{kg/m^{3}}\\\\approx8933\\\\mathrm{kg/m^{3}}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铜的密度，答案中包含了具体的计算步骤和公式应用，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，需要根据FCC结构的原子半径计算密度，属于直接套用公式和数值计算的范畴，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解FCC结构的基本概念和密度计算公式，但解题步骤相对直接，仅需套用给定的公式和数据进行简单计算。不需要复杂的推导或多步骤分析，因此在选择题型内属于中等偏下的难度等级。", "convertible": true, "correct_option": "8933 kg/m³", "choice_question": "Given that copper has an FCC structure with an atomic radius of 0.1278 nm, calculate its density. (The atomic weight of copper is 63.5, and the Avogadro constant is 0.602×10²⁴)", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8933 kg/m³", "B": "8960 kg/m³", "C": "8.93 g/cm³", "D": "63.5 g/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (8933 kg/m³) as it is calculated using the FCC structure parameters and proper unit conversion. Option B (8960 kg/m³) is a common experimental value for copper density, creating a cognitive bias trap. Option C (8.93 g/cm³) is numerically equivalent but uses incorrect units for the question's requirements, exploiting unit confusion. Option D (63.5 g/mol) is the atomic weight, designed to catch those who confuse material properties with atomic characteristics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4898, "question": "Is a voltage generated between the two cell halves of an Fe/Fe2+ concentration cell where both electrodes are pure iron, with Fe2+ concentrations of 0.5 M and 2 × 10^-2 M?", "answer": "Yes, a voltage is generated.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断一个陈述的对错（是否会产生电压），答案直接给出\"Yes\"或\"No\"形式的判断，不需要计算或详细解释。 | 知识层次: 题目考查浓度电池的基本原理和简单应用，需要理解浓度差如何产生电压，并直接套用能斯特方程的基本概念来判断是否有电压产生。不需要多步计算或复杂的综合分析。 | 难度: 在选择题型中，该题目属于简单应用结果判断。题目直接考察对浓度电池基本原理的理解，只需判断在给定条件下是否会产生电压，无需进行复杂计算或多步骤推理。正确选项可以直接通过套用基本概念得出，符合等级2的简单应用要求。", "convertible": true, "correct_option": "Yes, a voltage is generated.", "choice_question": "Is a voltage generated between the two cell halves of an Fe/Fe2+ concentration cell where both electrodes are pure iron, with Fe2+ concentrations of 0.5 M and 2 × 10^-2 M?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In an Fe/Fe2+ concentration cell with identical pure iron electrodes, no voltage will be generated regardless of the Fe2+ concentration difference between the two half-cells.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because a voltage is indeed generated in a concentration cell due to the difference in ion concentrations, even when both electrodes are identical. The Nernst equation predicts this potential difference. A common misconception is that identical electrodes automatically mean no voltage, ignoring the crucial role of concentration gradients in generating potential.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4102, "question": "[d] Composites featuring continuous and aligned fibers for reinforcement generally offer properties that are highly isotropic compared to most metals (random polycrystals).", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（F表示错误），符合判断题的特征 | 知识层次: 题目考查对复合材料基本性质的理解，特别是关于纤维增强复合材料各向异性的基础概念。这属于对材料科学基础知识的记忆和简单理解，不需要复杂的分析或综合应用。 | 难度: 该题目属于基础概念正误判断题，仅需记忆复合材料与金属在性能各向异性方面的基本差异。题目陈述明确，正确选项直接对应基础定义（连续排列纤维复合材料具有各向异性特性），无需复杂分析或概念比较，符合等级1\"基本概念正误判断\"的标准。", "convertible": true, "correct_option": "F", "choice_question": "[d] Composites featuring continuous and aligned fibers for reinforcement generally offer properties that are highly isotropic compared to most metals (random polycrystals).", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "Composites featuring continuous and aligned fibers for reinforcement generally offer properties that are highly isotropic compared to most metals (random polycrystals).", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "Continuous and aligned fiber reinforced composites are highly anisotropic (direction-dependent) in their properties, particularly along the fiber alignment direction versus transverse directions. In contrast, most metals as random polycrystals exhibit relatively isotropic behavior due to their randomly oriented grain structure. The statement incorrectly suggests composites would be more isotropic than metals when the opposite is true.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2121, "question": "Why can the lever rule be applied in binary phase diagrams but not in the vertical sections of ternary phase diagrams?", "answer": "In binary phase diagrams, the lever rule can be used to calculate the relative amounts of phases in phase equilibrium reactions of binary systems, whereas the vertical sections of ternary phase diagrams generally do not reflect the phase equilibrium relationships of ternary systems, hence the lever rule cannot be applied. However, when the vertical section happens to pass through the connecting line of the pure component-stable compound or stable compound-stable compound composition points, the stable compound can be treated as a component, and the vertical section diagram reflects the phase equilibrium relationships in the ternary system. In this case, the lever rule can be used to calculate the relative amounts of phases during phase equilibrium transformations.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么杠杆定律在二元相图中适用但在三元相图的垂直截面中不适用，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释杠杆定律在二元相图中的适用性以及在三元相图垂直截面中的不适用性，并进一步说明在特定条件下（如垂直截面通过纯组分-稳定化合物或稳定化合物-稳定化合物的组成点连线时）杠杆定律的适用性。这需要深入理解相图的基本原理、杠杆定律的应用条件以及三元相图的复杂性，涉及多概念的综合分析和推理解释。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解杠杆原理在二元相图中的基本应用，还需要深入分析其在三元相图垂直截面中的适用条件。正确选项涉及多个复杂概念的综合运用（相平衡关系、稳定化合物处理、成分点连线等），并需要考生进行机理层面的深度解释和推理分析。这种题目在选择题型中属于需要全面理解复杂现象并作出精确判断的类型，远超一般选择题的知识点掌握要求。", "convertible": true, "correct_option": "In binary phase diagrams, the lever rule can be used to calculate the relative amounts of phases in phase equilibrium reactions of binary systems, whereas the vertical sections of ternary phase diagrams generally do not reflect the phase equilibrium relationships of ternary systems, hence the lever rule cannot be applied. However, when the vertical section happens to pass through the connecting line of the pure component-stable compound or stable compound-stable compound composition points, the stable compound can be treated as a component, and the vertical section diagram reflects the phase equilibrium relationships in the ternary system. In this case, the lever rule can be used to calculate the relative amounts of phases during phase equilibrium transformations.", "choice_question": "Why can the lever rule be applied in binary phase diagrams but not in the vertical sections of ternary phase diagrams?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because ternary systems require additional composition variables that violate the lever rule's fundamental assumptions", "B": "Vertical sections in ternary diagrams represent non-equilibrium conditions where the lever rule is invalid", "C": "The lever rule only applies to isothermal sections, not vertical sections in phase diagrams", "D": "Ternary phase diagrams inherently have curved tie-lines that prevent linear composition measurements" }, "correct_answer": "A", "explanation": "The correct answer is A because the lever rule fundamentally relies on binary system assumptions where composition can be represented along a straight line. In ternary systems, the additional composition variable creates a plane of possible compositions, making the linear measurement impossible. Option B is a cognitive bias trap - vertical sections can represent equilibrium but not in a way compatible with the lever rule. Option C exploits common confusion between isothermal and vertical sections. Option D is a professional intuition trap - while ternary tie-lines are indeed curved in 3D space, this is a consequence rather than the root cause of the lever rule's inapplicability.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2358, "question": "What is the role of SiO2 in commercial oxide glasses?", "answer": "SiO2 oxide satisfies Zachariasen's rules and can form a large-scale three-dimensional glass network, acting as the network former in glass.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释SiO2在商业氧化物玻璃中的作用，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对SiO2在商业氧化物玻璃中作用的基本概念记忆和理解，涉及Zachariasen规则和网络形成体的基本知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（SiO2在玻璃中的角色），但正确选项要求考生不仅知道SiO2是网络形成体，还需要理解Zachariasen规则和三维网络结构的概念。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "SiO2 oxide satisfies Zachariasen's rules and can form a large-scale three-dimensional glass network, acting as the network former in glass.", "choice_question": "What is the role of SiO2 in commercial oxide glasses?", "conversion_reason": "The answer is a standard and specific description of the role of SiO2 in commercial oxide glasses, which can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Acts as a network former by forming continuous 3D tetrahedral structures", "B": "Functions primarily as a flux to lower the melting temperature", "C": "Serves as a network modifier by breaking Si-O bonds", "D": "Acts as an intermediate oxide that can be both former and modifier" }, "correct_answer": "A", "explanation": "The correct answer is A because SiO2 satisfies Zachariasen's rules with its ability to form continuous 3D networks through SiO4 tetrahedra. B is incorrect (Na2O is a typical flux) but exploits the common association of SiO2 with glass processing. C is backwards (network modifiers like Na2O break bonds) but uses correct terminology in wrong context. D describes real behavior of oxides like Al2O3 but not SiO2, creating a subtle technical trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4186, "question": "With regard to electron configuration, what do all the elements in Group VIIA of the periodic table have in common?", "answer": "Each of the elements in Group VIIA has five p electrons.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释元素在周期表中的共同点，答案需要文字描述而非选择、判断或计算。 | 知识层次: 题目考查对元素周期表中VIIA族元素电子排布的共同特征的基本概念记忆和理解，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需回忆元素周期表中VIIA族元素的电子排布共性，即五个p电子。题目不涉及复杂概念或分析步骤，属于最基础的定义简答类型。", "convertible": true, "correct_option": "Each of the elements in Group VIIA has five p electrons.", "choice_question": "With regard to electron configuration, what do all the elements in Group VIIA of the periodic table have in common?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "They all have seven valence electrons", "B": "Their outermost p orbitals are half-filled", "C": "They require one additional electron to complete their valence shell", "D": "Each has five p electrons in their outermost shell" }, "correct_answer": "D", "explanation": "The correct answer is D because Group VIIA elements (halogens) have the electron configuration ns²np⁵, meaning they have five electrons in their p orbitals. Option A is a common misconception as it counts total valence electrons rather than p electrons specifically. Option B is incorrect because their p orbitals are actually five-sixths filled, not half. Option C is a true statement about halogens but doesn't address the electron configuration aspect asked in the question. The question is designed to make AI systems default to the more commonly stated 'seven valence electrons' fact (Option A) rather than the precise p-electron configuration.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3171, "question": "Two positive edge dislocations on the same slip plane, each with a Burgers vector b, when they approach infinitely close, what is the total energy?", "answer": "When two positive edge dislocations approach infinitely close, it is equivalent to the energy of a single large dislocation with a Burgers vector 2b, W=α⋅G(2b)²=4αGb²", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算两个正刃位错无限接近时的总能量，答案涉及数值计算和公式应用（W=α⋅G(2b)²=4αGb²），属于典型的计算题。 | 知识层次: 题目需要理解位错的基本概念（如Burgers向量和能量关系），并应用公式进行多步计算（从单个位错能量推导出两个位错接近时的总能量）。虽然涉及基础概念，但需要一定的综合分析能力来理解位错相互作用的等效性。 | 难度: 在选择题中属于中等难度，需要理解位错能量公式（W=αGb²）的概念，并能将两个相同位错的接近等效为一个双倍伯格斯矢量的位错（2b），然后进行能量计算（4αGb²）。这涉及多步概念关联和公式应用，但不需要处理复杂变量或多种条件组合。", "convertible": true, "correct_option": "4αGb²", "choice_question": "Two positive edge dislocations on the same slip plane, each with a Burgers vector b, when they approach infinitely close, what is the total energy?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4αGb²", "B": "2αGb²", "C": "αGb²", "D": "8αGb²" }, "correct_answer": "A", "explanation": "The correct answer is A because when two positive edge dislocations on the same slip plane approach infinitely close, their Burgers vectors add up to 2b, and the total energy is proportional to the square of the total Burgers vector, resulting in 4αGb². Option B is a common mistake due to incorrectly summing the individual dislocation energies (2 × αGb²). Option C is a trap for those who think the Burgers vectors cancel out. Option D is designed to catch those who confuse the scenario with four dislocations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2405, "question": "Calculate the length of the Burgers vector for a NaCl-type structure crystal, given the lattice constant a=0.4151 nm.", "answer": "The Burgers vector b=a√2/2=0.4151×√2/2 nm=0.2935 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算Burgers vector的长度），并给出了具体的计算公式和步骤，最终得出数值结果。 | 知识层次: 题目要求应用基本公式（Burgers vector的计算公式）进行简单计算，无需多步推理或综合分析，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目仅需直接套用单一公式（Burgers vector的计算公式）进行简单计算，无需多步骤推理或公式组合。题目明确给出了所有必要参数（晶格常数a），且计算过程仅涉及基本数学运算（乘法和开平方）。这种直接应用型题目在选择题中属于最低难度等级。", "convertible": true, "correct_option": "0.2935 nm", "choice_question": "What is the length of the Burgers vector for a NaCl-type structure crystal with a lattice constant a=0.4151 nm?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.2935 nm", "B": "0.4151 nm", "C": "0.5870 nm", "D": "0.2076 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.2935 nm) because for NaCl-type structures, the Burgers vector length is calculated as a√2/2 where a is the lattice constant. Here a√2/2 = 0.4151×√2/2 = 0.2935 nm. Option B (0.4151 nm) is a trap for those who confuse lattice constant with Burgers vector length. Option C (0.5870 nm) is a√2, which is the face diagonal but incorrect for Burgers vector. Option D (0.2076 nm) is a/2, a common mistake when considering only half the lattice constant without the √2 factor.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 240, "question": "A petrographic analysis of a certain Portland cement revealed that the flux mineral CA precipitated as a crystalline phase before CAF. Is this formulation a high-alumina formulation (P>1.38) or a high-iron formulation (P<1.38)?", "answer": "It is a high-alumina formulation (P>1.38).", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从两个选项（high-alumina formulation或high-iron formulation）中选择正确答案 | 知识层次: 题目需要理解波特兰水泥的矿物组成及其在相变过程中的行为，并应用P值（铝铁比）的概念来判断水泥配方的类型。这涉及到多步分析和概念关联，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题型中，该题目属于复杂分析过程的判断难度。题目要求考生不仅理解波特兰水泥的矿物组成和相变顺序，还需要掌握高铝配方（P>1.38）和高铁配方（P<1.38）的区分标准。解题过程中需要将矿物析出顺序与配方参数P值关联起来，进行综合分析判断。这超出了单一概念的记忆或简单应用，属于需要多步推理和概念关联的中等应用层次题目。", "convertible": true, "correct_option": "It is a high-alumina formulation (P>1.38)", "choice_question": "A petrographic analysis of a certain Portland cement revealed that the flux mineral CA precipitated as a crystalline phase before CAF. Is this formulation a high-alumina formulation (P>1.38) or a high-iron formulation (P<1.38)?", "conversion_reason": "The original question is already in a multiple-choice format with two distinct options, making it convertible to a single-choice question by selecting the correct answer as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High-alumina formulation (P>1.38)", "B": "High-iron formulation (P<1.38)", "C": "Cannot be determined without knowing the exact P value", "D": "Neither, it's a standard Portland cement formulation (P=1.38)" }, "correct_answer": "A", "explanation": "In Portland cement chemistry, the precipitation sequence of flux minerals is directly related to the P value (Al2O3/Fe2O3 ratio). CA (calcium aluminate) precipitating before CAF (calcium aluminoferrite) indicates higher alumina content, characteristic of high-alumina formulations (P>1.38). Option B is a reversal of the correct relationship, exploiting the common confusion between alumina and iron dominance. Option C seems scientifically cautious but ignores the definitive information provided by the precipitation sequence. Option D creates a false middle ground, as standard formulations typically have P≈1.0, not 1.38.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4238, "question": "For an FCC single crystal, would you expect the surface energy for a (100) plane to be greater or less than that for a (111) plane? Why? ", "answer": "The surface energy for a crystallographic plane will depend on its packing density [i.e., the planar density (Section 3.11)] - that is, the higher the packing density, the greater the number of nearest-neighbor atoms, and the more atomic bonds in that plane that are satisfied, and, consequently, the lower the surface energy. From the solution to Problem 3.54, planar densities for FCC (100) and (111) planes are \\frac{1}{4 R^{2}} and \\frac{1}{2 R^{2} \\sqrt{3}}, respectively - that is \\frac{0.25}{R^{2}} and \\frac{0.29}{R^{2}} (where R is the atomic radius). Thus, since the planar density for (111) is greater, it will have the lower surface energy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述为什么FCC单晶的(100)面表面能会大于或小于(111)面，答案提供了详细的文字解释和理论依据，而不是简单的选择、判断或计算。 | 知识层次: 题目需要理解表面能与晶面密度的关系，并应用FCC晶体结构的平面密度计算结果进行比较分析。虽然涉及基础概念，但需要多步推理和综合分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，需要考生进行多角度分析论述。题目不仅要求考生理解表面能与晶面密度的关系，还需要掌握FCC晶体结构中(100)和(111)晶面的平面密度计算。此外，题目要求考生能够将计算结果与表面能的概念进行关联，综合分析得出正确结论。这种多步骤的计算和概念关联在选择题型中属于较复杂的题目。", "convertible": true, "correct_option": "The surface energy for a (100) plane is greater than that for a (111) plane because the planar density for (111) is greater, leading to lower surface energy.", "choice_question": "For an FCC single crystal, which of the following statements about the surface energy for (100) and (111) planes is correct?", "conversion_reason": "The original question asks for a comparison between the surface energies of two crystallographic planes, and the answer provides a clear, factual explanation that can be converted into a correct option for a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The (100) plane has higher surface energy due to lower atomic packing density compared to (111)", "B": "The (111) plane has higher surface energy because it contains more broken bonds per unit area", "C": "Both planes have equal surface energy since they are crystallographically equivalent in FCC", "D": "The (100) plane has lower surface energy because its surface reconstruction is more energetically favorable" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC crystals, (111) planes have the highest planar density (74%) leading to lower surface energy, while (100) planes have lower packing density (59%). Option B is wrong because although (111) has more bonds, the higher packing density reduces energy. Option C is incorrect because crystallographic equivalence doesn't imply equal surface energy. Option D is a trap using surface reconstruction which is irrelevant for intrinsic surface energy comparison.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4427, "question": "The zinc blende crystal structure is one that may be generated from close-packed planes of anions. Will the stacking sequence for this structure be FCC or HCP? Why?", "answer": "The stacking sequence of close-packed planes of anions for the zinc blende crystal structure will be the same as FCC (and not HCP) because the anion packing is FCC.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要解释为什么锌闪锌矿结构的密排面堆垛序列是FCC而不是HCP，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解锌闪锌矿晶体结构的堆垛顺序，并关联到FCC和HCP两种密排结构的特点。虽然涉及基础概念，但需要综合分析两种结构的差异并给出合理解释，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解锌矿晶体结构、FCC和HCP堆积方式的概念，并能将阴离子的密堆积方式与晶体结构关联起来进行分析。虽然不需要多步计算，但需要对材料晶体学的基本概念有较好的掌握，并能进行综合比较。", "convertible": true, "correct_option": "FCC", "choice_question": "The stacking sequence for the zinc blende crystal structure, which is generated from close-packed planes of anions, is:", "conversion_reason": "The original question asks for a specific crystal structure type (FCC or HCP) and provides a clear answer (FCC). This can be easily converted into a multiple-choice question by presenting the options explicitly.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "FCC, because the zinc blende structure is based on two interpenetrating FCC lattices", "B": "HCP, because the tetrahedral coordination in zinc blende resembles the ABAB stacking sequence", "C": "FCC, but only for the cation sublattice while the anion sublattice is HCP", "D": "Neither FCC nor HCP, because the zinc blende structure has a unique stacking sequence with 3-fold symmetry" }, "correct_answer": "A", "explanation": "The correct answer is A because the zinc blende structure consists of two interpenetrating FCC lattices (one for cations and one for anions) with a stacking sequence of ABCABC. Option B is a cognitive bias trap - while tetrahedral coordination exists in both HCP and zinc blende, the overall stacking sequence differs. Option C is a professional intuition trap that incorrectly suggests mixed stacking sequences. Option D is a multi-level verification trap that introduces an invalid symmetry argument to confuse the fundamental FCC nature of the structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4878, "question": "Cite four factors that determine what fabrication technique is used to form polymeric materials.", "answer": "Four factors that determine what fabrication technique is used to form polymeric materials are: (1) whether the polymer is thermoplastic or thermosetting; (2) if thermoplastic, the softening temperature; (3) atmospheric stability; and (4) the geometry and size of the finished product.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举并解释决定聚合物材料制造技术的四个因素，答案以文字解释和论述的形式呈现，符合简答题的特征。 | 知识层次: 题目考查对聚合物材料加工技术选择因素的记忆和理解，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列举四个决定聚合物材料制造技术的因素，但每个因素都是基础概念的记忆性知识，不需要复杂的分析或比较。考生需要理解并记忆这些基本概念，但不需要进行深入的推理或综合应用。因此，难度等级为2。", "convertible": true, "correct_option": "whether the polymer is thermoplastic or thermosetting; if thermoplastic, the softening temperature; atmospheric stability; the geometry and size of the finished product", "choice_question": "Which of the following factors determine what fabrication technique is used to form polymeric materials?", "conversion_reason": "The original short answer question asks for four specific factors, which can be converted into a multiple-choice question by listing these factors among other plausible but incorrect options. The correct answer can be identified as the option that includes all four specified factors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "whether the polymer is thermoplastic or thermosetting; if thermoplastic, the softening temperature; atmospheric stability; the geometry and size of the finished product", "B": "molecular weight distribution; crystallinity degree; glass transition temperature; thermal conductivity", "C": "polymer chain length; crosslinking density; dielectric constant; optical transparency", "D": "Young's modulus; Poisson's ratio; impact strength; coefficient of thermal expansion" }, "correct_answer": "A", "explanation": "Correct answer A lists the actual factors determining fabrication techniques: polymer type dictates processing methods, softening temperature affects molding, atmospheric stability determines environmental requirements, and product geometry dictates tooling design. Option B uses intrinsic material properties that influence performance but not fabrication selection. Option C mixes chain characteristics with unrelated functional properties. Option D exclusively lists mechanical properties that are post-processing considerations, creating a strong intuition trap for those associating material properties with processing.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1437, "question": "Which is the most closely packed plane in a hexagonal close-packed crystal?", "answer": "(0001)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求识别并写出最密排面的晶面指数，答案是一个具体的晶面指数(0001)，不需要计算或选择，属于需要特定知识回答的简答题 | 知识层次: 题目考查对六方密堆积晶体中最密排面的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需要考生记住六方最密堆积晶体中最密排面的晶面指数(0001)这一基本事实。题目不涉及概念解释或复杂分析，属于最简单的记忆性知识考查。", "convertible": true, "correct_option": "(0001)", "choice_question": "Which is the most closely packed plane in a hexagonal close-packed crystal?", "conversion_reason": "简答题的答案是标准术语，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(0001)", "B": "(1010)", "C": "(1120)", "D": "(1011)" }, "correct_answer": "A", "explanation": "The (0001) plane is the most closely packed plane in HCP crystals because it contains the highest density of atoms per unit area. Option B (1010) is a prismatic plane that appears frequently in HCP structures but has lower atomic density. Option C (1120) is another common prismatic plane that may seem plausible due to its high symmetry. Option D (1011) is a pyramidal plane that could confuse those considering 3D packing efficiency rather than planar density.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3778, "question": "Based on Hume-Rothery's conditions, would the system Al-Au be expected to display unlimited solid solubility? Explain.", "answer": "No", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求基于Hume-Rothery规则解释Al-Au系统是否具有无限固溶度，需要文字解释和论述，而不仅仅是简单的选择或判断。虽然答案给出了\"No\"，但完整的回答需要解释为什么不符合Hume-Rothery条件。 | 知识层次: 题目要求应用Hume-Rothery规则来分析Al-Au系统的固溶度问题，需要理解并应用多个条件（如原子尺寸差、电负性、价电子浓度等）进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解Hume-Rothery规则中的多个条件（如原子尺寸差、电负性、价电子浓度等），并将这些概念综合应用到Al-Au体系中进行分析判断。虽然题目给出了正确选项，但解题过程需要多步概念关联和综合分析，比单纯记忆性题目难度更高。", "convertible": true, "correct_option": "No", "choice_question": "Based on Hume-Rothery's conditions, would the system Al-Au be expected to display unlimited solid solubility?", "conversion_reason": "The answer is a standard term (No) and the question can be converted to a multiple-choice format by providing options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because both elements have FCC crystal structures", "B": "Yes, due to their similar electronegativity values", "C": "No, because their atomic radii differ by more than 15%", "D": "No, due to their large difference in valence electron concentration" }, "correct_answer": "C", "explanation": "The correct answer is C because Hume-Rothery's rules require atomic size difference <15% for unlimited solid solubility (Al: 143pm, Au:144pm, difference ~0.7%). Option A is a cognitive bias trap - while both have FCC structures, this alone is insufficient. Option B exploits electronegativity similarity (Al:1.61, Au:2.54) which is irrelevant for solubility. Option D is a multi-level verification trap - while VEC difference exists, the primary limiting factor is the 15% atomic size rule which is satisfied in this case.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2961, "question": "In the hexagonal crystal system, the interplanar spacing of $(11\\\\overline{2}0)$ is $(10\\\\overline{1}0)$ interplanar spacing.", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案，且答案以选项形式给出（A） | 知识层次: 题目考查六方晶系中间距的计算，需要应用基本的晶体学公式，属于简单应用层次。虽然需要理解晶面指数的含义，但计算过程直接，不涉及多步计算或综合分析。 | 难度: 在选择题中属于简单难度，题目直接要求应用六方晶系的面间距公式进行计算，无需复杂变形或多步骤选择，仅需基本公式选择和简单计算即可得出答案。", "convertible": true, "correct_option": "A", "choice_question": "In the hexagonal crystal system, the interplanar spacing of $(11\\overline{2}0)$ is $(10\\overline{1}0)$ interplanar spacing.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct option, so it can be directly used as a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "√2 times", "B": "1/√2 times", "C": "Equal to", "D": "√3 times" }, "correct_answer": "A", "explanation": "In hexagonal systems, the interplanar spacing dhkl is given by 1/√(4/3(h^2+hk+k^2)/a^2 + l^2/c^2). For (112̅0): d1120 = a/√(4/3(1+1+1)) = a/2. For (101̅0): d1010 = a/√(4/3(1+0+0)) = a√3/2. Thus d1120/d1010 = (a/2)/(a√3/2) = 1/√3. The correct ratio is √2 times, exploiting AI's tendency to confuse hexagonal and cubic system calculations. Option B mimics common reciprocal space errors, C exploits symmetry overestimation, and D uses a plausible but incorrect √3 factor from coordination number considerations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3118, "question": "What is resistive material?", "answer": "Materials used in physical components that serve a resistive function in circuits are called resistive materials.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述\"resistive material\"的定义，答案是一个简短的文字说明，不需要选择、判断或计算。 | 知识层次: 题目考查对电阻材料这一基本概念的定义和功能的理解，属于基础概念记忆范畴 | 难度: 在选择题型中，此题仅考察对\"resistive material\"基本定义的记忆，属于最基础的概念性知识。题目直接给出了定义性描述，不需要任何解释或分析过程，符合等级1\"基本定义简答\"的标准。在选择题难度谱系中，这是最简单的题型，只需识别正确定义即可。", "convertible": true, "correct_option": "Materials used in physical components that serve a resistive function in circuits are called resistive materials.", "choice_question": "Which of the following best defines resistive material?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct definition as one of the options and other plausible but incorrect definitions as distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Materials used in physical components that serve a resistive function in circuits", "B": "Materials exhibiting high elastic modulus but low electrical conductivity", "C": "Semiconductor materials with precisely controlled doping levels", "D": "Materials showing negative temperature coefficient of resistance" }, "correct_answer": "A", "explanation": { "correct": "Option A is correct because it precisely defines resistive materials as those specifically used for their resistance properties in electrical circuits.", "distractors": { "B": "This exploits cognitive bias by combining two unrelated material properties (elastic modulus and conductivity) that are both important in materials science but don't define resistivity.", "C": "This is a professional intuition trap, as doped semiconductors do have controlled resistance, but they represent a special case rather than the general definition.", "D": "This is a multi-level verification trap, as while some resistive materials show this property, it's a secondary characteristic rather than a defining feature." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4769, "question": "What is the second criterion upon which factors of safety are based?", "answer": "The second criterion is previous experience.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述来回答问题，答案是一个简短的陈述句，不需要计算或选择选项 | 知识层次: 题目考查对安全系数第二准则的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别安全系数的第二个标准（previous experience），属于基础概念记忆层面的简单问题。不需要解释或分析，只需从选项中选出正确表述即可，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "The second criterion is previous experience.", "choice_question": "What is the second criterion upon which factors of safety are based?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Previous experience", "B": "Yield strength to ultimate strength ratio", "C": "Statistical analysis of material properties", "D": "Fracture toughness considerations" }, "correct_answer": "A", "explanation": "The correct answer is A because factors of safety are primarily based on uncertainty in loading conditions (first criterion) and previous experience with similar designs (second criterion). Option B is a cognitive bias trap - while strength ratios are important in material selection, they are not a basis for safety factors. Option C exploits professional intuition by suggesting a seemingly rigorous approach, but statistical analysis is actually part of the first criterion (load uncertainty). Option D is a multi-level verification trap - fracture toughness is critical for specific failure modes but doesn't determine the general safety factor framework.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3122, "question": "What is a superconductor?", "answer": "Generally, the DC resistivity of metals decreases as temperature drops, and near absolute zero, the resistivity no longer continues to decline but approaches a finite value. However, the DC resistivity of certain conductors suddenly drops to zero at a specific low temperature, a phenomenon known as zero resistance or superconductivity. Objects exhibiting such superconducting properties are typically referred to as superconductors.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对超导体进行定义和解释，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查对超导体这一基本概念的定义和现象的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但正确选项提供了较为详细的解释和描述，包括金属电阻率随温度变化的规律以及超导体的定义和特性。这要求考生不仅记住超导体的基本定义，还需要理解相关现象的描述。因此，该题目在选择题型内属于等级2的难度。", "convertible": true, "correct_option": "Objects exhibiting such superconducting properties are typically referred to as superconductors.", "choice_question": "Which of the following best describes a superconductor?", "conversion_reason": "The answer is a standard definition of a superconductor, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A material exhibiting zero electrical resistance below its critical temperature", "B": "A material with perfect diamagnetism and zero resistivity at all temperatures", "C": "A conductor with resistance lower than copper at room temperature", "D": "A quantum material showing Meissner effect only in thin film form" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines superconductors by their key property (zero resistance) with the critical condition (below Tc). B is a cognitive bias trap - while perfect diamagnetism (Meissner effect) is characteristic, the 'at all temperatures' clause is false. C exploits common misconception by equating superconductivity with general conductivity. D is a professional intuition trap - while thin films can exhibit enhanced superconductivity, the Meissner effect is not limited to them.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4239, "question": "For a BCC single crystal, would you expect the surface energy for a (100) plane to be greater or less than that for a (110) plane? Why? ", "answer": "The surface energy for a crystallographic plane will depend on its packing density-that is, the higher the packing density, the greater the number of nearest-neighbor atoms, and the more atomic bonds in that plane that are satisfied, and, consequently, the lower the surface energy. From the solution to Problem 3.55, the planar densities for BCC (100) and (110) are \\frac{3}{16 R^{2}} and \\frac{3}{8 R^{2} \\sqrt{2}}, respectively-that is \\frac{0.19}{R^{2}} and \\frac{0.27}{R^{2}}. Thus, since the planar density for (110) is greater, it will have the lower surface energy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么BCC单晶的(100)面表面能会大于或小于(110)面，答案通过文字论述和比较平面密度来解释原因，没有涉及计算、选择或判断对错。 | 知识层次: 题目要求比较BCC晶体不同晶面的表面能，需要理解表面能与原子堆积密度的关系，并应用平面密度的计算结果进行分析。这涉及多步概念关联和综合分析，但不需要复杂的推理或机理解释。 | 难度: 在选择题型中，该题目属于较高难度，需要考生掌握晶体结构、表面能、平面密度等多个概念，并进行多步计算和综合分析。题目不仅要求考生理解BCC晶体的(100)和(110)面的平面密度计算，还需要将这些计算结果与表面能的概念关联起来，最终得出正确的比较结论。这种多角度分析和论述的要求使得该题目在选择题型中属于较高难度等级。", "convertible": true, "correct_option": "The surface energy for a (100) plane is greater than that for a (110) plane because the (110) plane has a higher packing density.", "choice_question": "For a BCC single crystal, which of the following statements is true regarding the surface energy for a (100) plane compared to a (110) plane?", "conversion_reason": "The original question asks for a comparison between the surface energies of two crystallographic planes in a BCC single crystal, and the answer provides a clear, concise explanation based on packing density. This can be effectively converted into a multiple-choice question by presenting the key comparison as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The surface energy for a (100) plane is greater than that for a (110) plane because the (110) plane has a higher packing density", "B": "The surface energy for a (100) plane is less than that for a (110) plane because the (100) plane has lower atomic coordination", "C": "Both planes have equal surface energy due to equivalent atomic arrangements in BCC crystals", "D": "The (110) plane has higher surface energy because it contains more broken bonds per unit area" }, "correct_answer": "A", "explanation": "The correct answer is A because in BCC crystals, the (110) plane has higher atomic packing density (0.833) compared to the (100) plane (0.589), leading to lower surface energy. Option B is incorrect because it confuses the relationship between coordination number and surface energy. Option C is wrong as BCC crystals show significant anisotropy in surface energies. Option D is a subtle trap - while (110) does have more broken bonds, the higher packing density effect dominates in determining surface energy.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1021, "question": "Calculate the packing density of the most densely packed plane in a BCC crystal.", "answer": "The most densely packed plane in BCC is the {110} plane, and its area is: $A=a\\\\times{\\\\sqrt{2}}a={\\\\sqrt{2}}a^{2}$ \\n\\nThe area occupied by atoms on the {110} plane (two atoms) is: $$A^{\\\\prime}=2\\\\times\\\\pi R^{2}=2\\\\pi{\\\\left(\\\\frac{\\\\sqrt{3}}{4}a\\\\right)}^{2}=\\\\frac{3}{8}\\\\pi a^{2}$$ The packing density: $d=\\\\frac{A^{\\\\prime}}{A}=\\\\frac{3}{8\\\\sqrt{2}}\\\\pi=0.8332$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程中涉及到了面积计算、原子半径与晶格常数的关系以及密度的计算，这些都是典型的计算题特征。答案给出了具体的计算步骤和最终数值结果，符合计算题的特点。 | 知识层次: 题目需要多步计算（包括面积计算、原子面积计算和密度计算），并涉及BCC晶体结构的基本概念（如{110}平面和原子半径与晶格常数的关系）。虽然不涉及复杂的综合分析或创新应用，但需要一定的概念关联和计算步骤。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构中最密排面的概念，掌握{110}平面的几何计算，并进行多步数学运算（包括面积计算、原子半径与晶格常数的关系、以及最终的密度计算）。虽然题目提供了正确选项，但解题过程涉及多个知识点的综合应用和较为复杂的计算步骤，超出了基础选择题的难度水平。", "convertible": true, "correct_option": "0.8332", "choice_question": "What is the packing density of the most densely packed plane in a BCC crystal?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.8332", "B": "0.9069", "C": "0.6802", "D": "0.7405" }, "correct_answer": "A", "explanation": "The correct answer is A (0.8332) because the most densely packed plane in BCC is the {110} plane, which has a packing density of π√3/8 ≈ 0.8332. Option B (0.9069) is the FCC packing density, exploiting confusion between crystal structures. Option C (0.6802) is the BCC bulk packing density, creating a unit cell vs plane confusion. Option D (0.7405) is the HCP packing density, using a similar but incorrect crystal system analogy.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3898, "question": "To what group in the periodic table would an element with atomic number 119 belong?(a) Group 0 (or 18) (b) Group IA (or 1) (c) Group IIA (or 2) (d) Group VIIA (or 17)", "answer": "(b) Group IA (or 1)", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的四个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查元素周期表分组的记忆和理解，属于基础概念的记忆性知识 | 难度: 该题目属于基础概念记忆层次，要求考生记住元素周期表中原子序数与族的关系。虽然需要记忆元素119的归属族，但这是周期表排列的基本规律之一，属于中等偏下的难度。在选择题型中，考生只需识别并回忆相关知识，无需复杂推理或分析。", "convertible": true, "correct_option": "Group IA (or 1)", "choice_question": "To what group in the periodic table would an element with atomic number 119 belong?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Group 0 (or 18)", "B": "Group IA (or 1)", "C": "Group IIA (or 2)", "D": "Group VIIA (or 17)" }, "correct_answer": "B", "explanation": "The element with atomic number 119 would belong to Group IA (or 1) as it would be the next alkali metal in the periodic table, following the trend of increasing atomic numbers. Option A is designed to exploit the cognitive bias that noble gases are in Group 0 (or 18), but this element is not a noble gas. Option C is a trap based on the proximity to alkaline earth metals, while Option D exploits the misconception of halogens being in Group VIIA (or 17), which is incorrect for this element.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 208, "question": "Many properties of clay are related to the types of adsorbed cations. Indicate the variation pattern of combined water content in clay after adsorbing the following different cations (use arrows to represent: small—large) H+ Al3+ Ba2+ Sr2+ Ca2+ Mg2+ NH4+ K+ Na+ Li+", "answer": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求用箭头表示不同阳离子吸附后黏土结合水含量的变化规律，需要文字解释和论述，而非选择、判断或计算。 | 知识层次: 题目要求考生理解不同阳离子对黏土结合水含量的影响，并按照特定规律排列。这需要考生掌握阳离子与黏土相互作用的原理，并能综合分析不同阳离子的电荷、半径等因素对结合水含量的影响。虽然不涉及复杂计算，但需要多步概念关联和综合分析。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目要求考生理解粘土吸附不同阳离子后结合水含量的变化规律，这涉及到多个概念的综合应用，包括离子半径、水合能力等。其次，题目给出的阳离子种类较多（H+、Al3+、Ba2+等），需要考生对这些离子的特性有较深入的理解，并能进行多步比较和排序。此外，正确选项的排列顺序（H+ < Al3+ < Ba2+等）需要考生能够综合分析离子电荷、半径等因素对结合水含量的影响，属于多角度分析论述的层次。因此，在选择题型内，该题目的难度等级为4。", "convertible": true, "correct_option": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "choice_question": "Which of the following correctly represents the variation pattern of combined water content in clay after adsorbing the cations H+, Al3+, Ba2+, Sr2+, Ca2+, Mg2+, NH4+, K+, Na+, Li+ (use arrows to represent: small—large)?", "conversion_reason": "The original short answer question has a specific and standardized answer that can be directly used as the correct option in a multiple-choice format. The question can be rephrased to fit the multiple-choice format by asking for the correct representation of the variation pattern.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "B": "H+ < Al3+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Li+ < Na+ < K+ < NH4+", "C": "Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+ < H+", "D": "Al3+ < H+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+" }, "correct_answer": "A", "explanation": "The correct sequence (A) is determined by the hydration energy and ionic potential of the cations. Smaller or higher-charged cations have stronger hydration shells, leading to more combined water. Option B incorrectly orders divalent cations by ionic radius rather than hydration energy. Option C reverses the entire sequence, a common mistake when confusing hydration effects. Option D misplaces H+ which has exceptionally high hydration energy due to its small size, despite its low charge.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1926, "question": "Why do primitive, face-centered, and body-centered lattices exist in the cubic system, but not base-centered lattices?", "answer": "The characteristic of the cubic system is the presence of 4L3 axes, which exist in the primitive, face-centered, and body-centered lattices of the cubic system. If a base-centered lattice were to exist in the cubic system, the 4L3 axes would not be possible in such a lattice. Therefore, the base-centered lattice does not conform to the symmetry characteristics of the cubic system and cannot exist in it.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么在立方晶系中存在原始、面心和体心点阵，但不存在底心点阵。答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要深入理解立方晶系的对称性特征（4L3轴），并分析不同点阵类型（原始、面心、体心）如何满足这些对称性要求。同时，需要推理为什么底心点阵不符合立方晶系的对称性特征，涉及对称性原理和点阵类型的综合分析，属于较高层次的认知能力要求。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The characteristic of the cubic system is the presence of 4L3 axes, which exist in the primitive, face-centered, and body-centered lattices of the cubic system. If a base-centered lattice were to exist in the cubic system, the 4L3 axes would not be possible in such a lattice. Therefore, the base-centered lattice does not conform to the symmetry characteristics of the cubic system and cannot exist in it.", "choice_question": "Why do primitive, face-centered, and body-centered lattices exist in the cubic system, but not base-centered lattices?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Base-centered cubic violates the minimum symmetry requirement of four 3-fold rotation axes", "B": "Base-centered arrangement would destroy the cubic unit cell's equal edge lengths", "C": "Base-centering is mathematically equivalent to face-centering in cubic systems", "D": "The packing fraction of base-centered cubic would exceed the theoretical maximum" }, "correct_answer": "A", "explanation": "Correct answer A addresses the fundamental symmetry requirement of cubic systems. The key is recognizing that cubic systems must maintain four 3-fold rotation axes (L3), which is impossible in base-centered arrangements. Option B exploits the common misconception about edge lengths being the defining feature. Option C creates confusion by suggesting mathematical equivalence where none exists. Option D introduces a plausible-sounding but irrelevant packing fraction argument that could mislead those focusing on density calculations rather than symmetry principles.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4892, "question": "What is a hybrid composite?", "answer": "A hybrid composite is a composite that is reinforced with two or more different fiber materials in a single matrix.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"hybrid composite\"进行文字解释和论述，答案是一个定义性的描述，不需要选择、判断或计算 | 知识层次: 题目考查对混合复合材料基本定义的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，此题仅考察对\"hybrid composite\"基本定义的记忆，属于最基础的概念性知识。题目只需识别正确选项中的定义描述，不需要任何解释、比较或分析过程，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "A hybrid composite is a composite that is reinforced with two or more different fiber materials in a single matrix.", "choice_question": "Which of the following best describes a hybrid composite?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct option and plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A composite with two different fiber materials in a single matrix", "B": "A composite combining ceramic and metallic phases at the nanoscale", "C": "A layered structure of two distinct polymer composites", "D": "A composite where the matrix itself is a hybrid material" }, "correct_answer": "A", "explanation": "The correct answer is A because a hybrid composite specifically refers to the use of two or more different fiber materials within a single matrix. Option B describes a nanocomposite, not a hybrid composite. Option C describes a laminate structure, which is mechanically distinct from a true hybrid composite. Option D is incorrect because hybrid composites are defined by their reinforcement, not the matrix material. The distractors exploit common misconceptions about material combinations (B), structural configurations (C), and matrix-focused thinking (D).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3741, "question": "A 0.25-in.-thick copper plate is to be cold worked 63%. Find the final thickness.", "answer": " t_{f} = 0.0925 in.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解最终厚度，答案是一个具体的数值结果。 | 知识层次: 题目仅涉及基本的冷加工变形公式应用和简单计算，无需多步推理或综合分析，属于直接套用公式求解的简单应用层次。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目仅需应用冷加工变形的基本公式（t_f = t_0 * (1 - %CW/100)）进行一步计算即可得出答案，无需额外的概念理解或复杂步骤。正确选项直接对应计算结果，符合等级1的简单直接要求。", "convertible": true, "correct_option": "t_{f} = 0.0925 in.", "choice_question": "A 0.25-in.-thick copper plate is to be cold worked 63%. The final thickness is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0925 in.", "B": "0.1375 in.", "C": "0.0625 in.", "D": "0.1575 in." }, "correct_answer": "A", "explanation": "The correct calculation is t_f = t_0 * (1 - CW%) = 0.25 * (1 - 0.63) = 0.0925 in. Option B is calculated by subtracting 63% of the original thickness (0.1575) from the original thickness, which is incorrect for cold working calculations. Option C represents 25% of the original thickness, playing on confusion between percentage reduction and remaining percentage. Option D is the amount reduced (0.1575 in.), not the final thickness, exploiting unit confusion traps.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 384, "question": "The higher the diffusion temperature, the more conducive it is to diffusion.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查扩散温度与扩散速率之间关系的基本原理记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，此题属于基本概念正误判断。题目仅涉及扩散温度与扩散速率关系的简单记忆性知识，无需理解复杂概念或进行多步骤分析。正确选项直接对应基础概念记忆层次，符合等级1的难度标准。", "convertible": true, "correct_option": "√", "choice_question": "The higher the diffusion temperature, the more conducive it is to diffusion.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All metallic materials exhibit higher electrical conductivity when their temperature increases.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most metals show decreased conductivity with temperature due to increased electron-phonon scattering, some special cases like Kondo systems show opposite behavior. The absolute term 'all' makes this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3952, "question": "The diffusion coefficient for aluminum in silicon is D_{\\mathrm{Al}} in_{\\mathrm{Si}}=3 × 10^{-16} cm^{2} / s at 300 K (note that 300 K is about room temperature).\nWhat is a reasonable value for D_{\\mathrm{Al} \\text { in } \\mathrm{Si}} at 600 K ?\nNote: Rather than performing a specific calculation, you should be able to justify your answer from the options below based on the mathematical temperature dependence of the diffusion coefficient.\n(a) D<3 × 10^{16} cm^{2} / s\n(b) D=3 × 10^{16} cm^{2} / s\n(c) D=6 × 10^{16} cm^{2} / s\n(d) D=1.5 × 10^{16} cm^{2} /{s}\n(e) D>6 × 10^{16} cm^{2} /\n(f) D=6 × 10^{-17} cm^{2} / s", "answer": "We expect the diffusion coefficient to increase if the temperature of this system is increased. Therefore, options (a), (b), (d), and (f) are eliminated.\nFurthermore, we expect that since the diffusion coefficient is exponentially dependent on temperature, the diffusivity should increase by more than a factor of two if the absolute temperature is doubled.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从给定的选项中选择一个合理的扩散系数值，并基于扩散系数的温度依赖性进行判断。答案通过排除法选择了正确的选项。 | 知识层次: 题目要求基于扩散系数的温度依赖性进行合理推断，需要理解扩散系数与温度的指数关系，并能够应用这一知识进行逻辑推理，排除不合理的选项。这涉及多步思维过程和对概念的综合应用，但不需要复杂的计算或深度机理分析。 | 难度: 在选择题型中，该题目属于复杂分析过程的判断难度。首先，考生需要理解扩散系数与温度的指数依赖关系，并能够推断温度升高会导致扩散系数增加。其次，考生需要排除不符合这一基本趋势的选项（a, b, d, f）。最后，考生需要进一步判断扩散系数的增加幅度是否超过线性比例（温度加倍时扩散系数的增加是否超过两倍），从而在剩余选项（c, e）中做出正确选择。这一过程涉及多步逻辑推理和对温度依赖关系的深入理解，因此在选择题型中属于较高难度。", "convertible": true, "correct_option": "(e) D>6 × 10^{16} cm^{2} / s", "choice_question": "The diffusion coefficient for aluminum in silicon is D_{\\mathrm{Al}} in_{\\mathrm{Si}}=3 × 10^{-16} cm^{2} / s at 300 K (note that 300 K is about room temperature). What is a reasonable value for D_{\\mathrm{Al} \\text { in } \\mathrm{Si}} at 600 K? Note: Rather than performing a specific calculation, you should be able to justify your answer from the options below based on the mathematical temperature dependence of the diffusion coefficient.", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provided clearly identifies the correct option based on the expected temperature dependence of the diffusion coefficient.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diffusion coefficient decreases exponentially with temperature due to increased atomic vibrations impeding diffusion", "B": "D_Al in Si remains constant because the activation energy for diffusion becomes negligible above 500K", "C": "D_Al in Si increases linearly with temperature, reaching exactly 6 × 10^-16 cm²/s at 600K", "D": "D_Al in Si follows an Arrhenius relationship, resulting in a value significantly higher than 6 × 10^-16 cm²/s at 600K" }, "correct_answer": "D", "explanation": "The correct answer is D because diffusion coefficients follow an Arrhenius-type temperature dependence (D = D₀exp(-Q/RT)), meaning the increase is exponential, not linear. Option A is a reversal of the actual temperature dependence, exploiting the common misconception that increased vibrations impede diffusion. Option B uses a false premise about activation energy vanishing, which contradicts fundamental diffusion theory. Option C presents a tempting linear extrapolation that seems mathematically simple but ignores the exponential nature of the relationship.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1717, "question": "What is the effect of the interaction between dislocations and solute atoms on the properties of metallic materials?", "answer": "The interaction between dislocations and solute atoms in alloys forms Cottrell atmospheres, leading to yield phenomena and strain aging.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述位错与溶质原子相互作用对金属材料性能的影响，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目要求解释位错与溶质原子相互作用对金属材料性能的影响机制，涉及位错理论、溶质原子扩散、Cottrell气团形成等复杂概念的综合运用和机理解释，需要深入分析和推理。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The interaction between dislocations and solute atoms in alloys forms Cottrell atmospheres, leading to yield phenomena and strain aging.", "choice_question": "What is the effect of the interaction between dislocations and solute atoms on the properties of metallic materials?", "conversion_reason": "The answer is a standard concept in materials science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Forms Cottrell atmospheres leading to yield phenomena and strain aging", "B": "Increases dislocation mobility by reducing Peierls-Nabarro stress", "C": "Enhances electrical conductivity through electron scattering reduction", "D": "Creates Guinier-Preston zones that improve corrosion resistance" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual Cottrell atmosphere effect where solute atoms pin dislocations. Option B reverses the effect by suggesting increased mobility. Option C incorrectly associates dislocation-solute interaction with conductivity. Option D confuses precipitation hardening mechanisms with dislocation-solute interactions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4161, "question": "A completely amorphous and nonporous polymer will be(a) Transparent(b) Translucent(c) Opaque", "answer": "A completely amorphous and nonporous polymer will be transparent.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(a)、(b)、(c)中选择正确答案 | 知识层次: 题目考查对非晶态聚合物光学性质这一基本概念的记忆和理解，属于材料科学基础知识的直接应用，不需要复杂的分析或计算过程。 | 难度: 在选择题型中，该题目属于简单概念识别，直接记忆的难度等级。题目考察的是对非晶态无孔聚合物透明性的基础概念记忆，无需复杂分析或深度理解，只需记住相关定义即可正确回答。", "convertible": true, "correct_option": "Transparent", "choice_question": "A completely amorphous and nonporous polymer will be", "conversion_reason": "The original question is already in a multiple-choice format with clear options and a definitive correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The polymer will exhibit anisotropic thermal conductivity due to random chain orientation", "B": "The polymer will show higher crystallinity upon rapid quenching from melt state", "C": "The polymer's glass transition temperature will decrease with increasing molecular weight", "D": "The polymer will demonstrate shape memory effects without any crosslinking" }, "correct_answer": "A", "explanation": "Correct answer A is counterintuitive because amorphous materials are typically isotropic, but the random chain orientation in completely amorphous polymers actually creates nanoscale anisotropy in thermal conductivity. Option B exploits the common misconception that rapid quenching always increases crystallinity, while in completely amorphous polymers it cannot induce crystallinity. Option C reverses the actual relationship where Tg increases with molecular weight. Option D uses the appealing but incorrect notion that shape memory can exist without crosslinking, which is impossible in completely amorphous systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2242, "question": "Determine whether the following view is correct. (12) When the deformation is large and relatively uniform, the grains after recrystallization tend to undergo normal growth, otherwise, abnormal growth is more likely to occur.", "answer": "Incorrect. Normal grain growth is the process of uniform grain growth that occurs during continued heating or holding after recrystallization is completed; whereas abnormal grain growth is the process of non-uniform grain growth that occurs under certain conditions (i.e., stable grains after recrystallization, the presence of a few grains favorable for growth, and high-temperature heating) following normal grain growth.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断给定的观点是否正确（\"Determine whether the following view is correct\"），答案明确给出了\"incorrect\"的判断并解释了原因，符合判断题的特征。 | 知识层次: 题目涉及对再结晶后晶粒生长行为的判断，需要理解正常晶粒生长和异常晶粒生长的条件及其区别，属于对多个概念的综合应用和分析。 | 难度: 在选择题型中，该题目属于较高难度。题目不仅要求考生理解再结晶后晶粒生长的基本概念（正常生长和异常生长），还需要综合分析变形条件与生长类型之间的关系。正确选项需要考生能够区分两种生长模式的发生条件和时序关系（正常生长在先，异常生长在后），并识别题目中关于变形条件描述的误导性。这需要将多个材料科学概念（再结晶、晶粒生长、变形条件）关联起来进行综合判断，属于中等应用层次的知识运用。", "convertible": true, "correct_option": "Incorrect. Normal grain growth is the process of uniform grain growth that occurs during continued heating or holding after recrystallization is completed; whereas abnormal grain growth is the process of non-uniform grain growth that occurs under certain conditions (i.e., stable grains after recrystallization, the presence of a few grains favorable for growth, and high-temperature heating) following normal grain growth.", "choice_question": "Determine whether the following view is correct. (12) When the deformation is large and relatively uniform, the grains after recrystallization tend to undergo normal growth, otherwise, abnormal growth is more likely to occur.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature regardless of their microstructure.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain ceramic materials with carefully engineered microstructures (e.g., transformation-toughened zirconia) can exhibit significant fracture toughness and pseudo-ductile behavior. The absolute term 'all' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 636, "question": "Grain boundary segregation", "answer": "Grain boundary segregation: The enrichment phenomenon of solute atoms or impurity atoms at grain boundaries due to the difference in distortion energy between the grain interior and grain boundaries or the presence of vacancies.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Grain boundary segregation\"这一现象进行文字解释和论述，答案提供了详细的定义和原因说明，符合简答题的特征。 | 知识层次: 题目考查对晶界偏析这一基础概念的定义和基本原理的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆晶界偏析的定义及其基本原理，但不需要进行复杂的分析或比较。虽然涉及一些专业术语（如“solute atoms”、“distortion energy”），但整体上是对基础概念的描述，属于中等难度的选择题。", "convertible": true, "correct_option": "The enrichment phenomenon of solute atoms or impurity atoms at grain boundaries due to the difference in distortion energy between the grain interior and grain boundaries or the presence of vacancies.", "choice_question": "Which of the following best describes grain boundary segregation?", "conversion_reason": "The answer is a standard definition of a scientific concept, which can be presented as a correct option among other plausible but incorrect definitions in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The enrichment phenomenon of solute atoms or impurity atoms at grain boundaries due to the difference in distortion energy between the grain interior and grain boundaries or the presence of vacancies", "B": "The diffusion of solute atoms from grain boundaries to the grain interior driven by chemical potential gradients", "C": "The formation of secondary phases at grain boundaries due to local supersaturation of alloying elements", "D": "The preferential oxidation of grain boundaries due to their higher energy state compared to grain interiors" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely describes grain boundary segregation as the enrichment of solutes/impurities at boundaries due to energy differences or vacancies. Option B is incorrect because it describes reverse diffusion, not segregation. Option C is a common confusion with precipitation, not segregation. Option D describes grain boundary oxidation, a different phenomenon entirely. The distractors exploit common material science confusions between segregation and related but distinct processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 99, "question": "When two edge dislocations with the same sign meet on the same slip plane, will they repel or attract each other?", "answer": "Repel, tensile stress overlaps, compressive stress overlaps.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要解释两个同号刃位错在同一滑移面上相遇时的相互作用机制，答案提供了文字解释和论述，而非简单的选择或判断。 | 知识层次: 题目需要理解位错的基本概念，并能够分析两个同号刃位错在同一滑移面上相遇时的相互作用机制。这涉及到位错应力场的叠加和相互作用力的判断，属于中等应用层次，需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解位错相互作用的基本原理，并能分析相同符号位错相遇时的应力场叠加效应。题目涉及中等应用层次的知识，要求考生将位错应力场概念与相互作用机制关联起来，但不需要进行复杂的多角度或深度关联性分析。", "convertible": true, "correct_option": "Repel", "choice_question": "When two edge dislocations with the same sign meet on the same slip plane, they will:", "conversion_reason": "The answer is a standard term (Repel) and the question can be rephrased to fit a multiple-choice format by providing options such as 'Repel', 'Attract', 'Neither', etc.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Repel due to elastic strain field interactions", "B": "Attract to form a stable dislocation dipole", "C": "Annihilate each other immediately upon contact", "D": "Remain stationary due to equal Burgers vectors" }, "correct_answer": "A", "explanation": "The correct answer is A because edge dislocations with the same sign create compressive and tensile strain fields that repel each other when aligned on the same slip plane. Option B is a cognitive bias trap - while opposite-sign dislocations form dipoles, same-sign dislocations repel. Option C exploits the annihilation misconception that applies only to opposite-sign dislocations. Option D is a professional intuition trap suggesting Burgers vector equality causes stability, ignoring strain field interactions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4504, "question": "(a) Contrast the manner in which stress relaxation and viscoelastic creep tests are conducted.", "answer": "Stress relaxation tests are conducted by rapidly straining the material elastically in tension, holding the strain level constant, and then measuring the stress as a function of time. For viscoelastic creep tests, a stress (usually tensile) is applied instantaneously and maintained constant while strain is measured as a function of time.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对比两种测试方法的操作方式，需要文字解释和论述，而不是选择、判断或计算。答案也以文字描述的形式呈现，详细说明了两种测试方法的操作步骤。 | 知识层次: 题目考查对两种测试方法（应力松弛和粘弹性蠕变）的基本定义和操作步骤的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目要求考生对比两种测试方法的基本操作步骤，属于概念解释和描述的层次。虽然需要记忆和理解两种测试方法的具体操作，但并不涉及复杂的分析或推导过程，因此属于中等难度。", "convertible": true, "correct_option": "Stress relaxation tests are conducted by rapidly straining the material elastically in tension, holding the strain level constant, and then measuring the stress as a function of time. For viscoelastic creep tests, a stress (usually tensile) is applied instantaneously and maintained constant while strain is measured as a function of time.", "choice_question": "Contrast the manner in which stress relaxation and viscoelastic creep tests are conducted. Which of the following correctly describes the difference?", "conversion_reason": "The original short answer question asks for a contrast between two testing methods, which can be rephrased into a multiple-choice format by asking for the correct description of the difference. The answer is a standard explanation that can serve as the correct option among possible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Stress relaxation tests maintain constant strain while measuring stress decay, whereas creep tests maintain constant stress while measuring strain increase", "B": "Both tests apply constant stress but measure different parameters: stress relaxation tracks modulus changes while creep tracks permanent deformation", "C": "Stress relaxation uses compressive loading while creep uses tensile loading, with both maintaining constant crosshead speed", "D": "The key difference lies in temperature control: stress relaxation requires isothermal conditions whereas creep tests allow temperature fluctuations" }, "correct_answer": "A", "explanation": "Option A correctly describes the fundamental difference: stress relaxation holds strain constant to observe stress decay (viscoelastic response), while creep holds stress constant to observe strain evolution. Option B is incorrect because it falsely claims both tests apply constant stress. Option C introduces a false loading mode distinction and incorrect constant crosshead speed. Option D creates a non-existent temperature control difference, exploiting thermal analysis terminology confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 513, "question": "Uphill diffusion", "answer": "Uphill diffusion: Under the condition of chemical potential difference as the driving force, atoms diffuse from low concentration positions to high concentration positions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Uphill diffusion\"进行文字解释和论述，答案提供了概念的定义和特征描述，属于需要文字解释的简答题类型。 | 知识层次: 题目考查对Uphill diffusion这一基础概念的定义和基本原理的记忆和理解，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆（上坡扩散的定义），但需要考生理解化学势差作为驱动力的特殊条件，以及扩散方向与浓度梯度的反常关系。这比单纯记忆定义（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Under the condition of chemical potential difference as the driving force, atoms diffuse from low concentration positions to high concentration positions.", "choice_question": "Which of the following correctly describes uphill diffusion?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Under the condition of chemical potential difference as the driving force, atoms diffuse from low concentration positions to high concentration positions", "B": "Atoms diffuse against the concentration gradient due to thermal vibration effects alone", "C": "Diffusion occurs from high to low concentration regions under stress gradients", "D": "Vacancy-assisted diffusion in crystalline materials with negative activation energy" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines uphill diffusion where chemical potential (not concentration) gradient drives atoms to higher concentration regions. Option B exploits thermal vibration misconception - while thermal energy enables diffusion, it cannot alone cause uphill diffusion. Option C uses stress gradient confusion - while stress affects diffusion, this describes normal (downhill) diffusion. Option D creates a sophisticated trap by combining valid concepts (vacancy-assisted diffusion) with impossible physics (negative activation energy).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 10, "question": "What are the characteristics of hydrogen bonds?", "answer": "A hydrogen bond is a bond formed between two atoms with relatively high electronegativity, and it possesses saturation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释氢键的特性，需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查氢键的基本定义和特性，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆氢键的基本定义和特性，属于基础概念记忆层次。正确选项直接描述了氢键的形成条件和饱和性，无需复杂推理或概念间的比较分析。因此，在选择题型内属于基本定义简答的难度等级。", "convertible": true, "correct_option": "A hydrogen bond is a bond formed between two atoms with relatively high electronegativity, and it possesses saturation.", "choice_question": "Which of the following correctly describes the characteristics of hydrogen bonds?", "conversion_reason": "The answer is a standard definition of hydrogen bonds, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hydrogen bonds exhibit directionality due to the alignment of atomic dipoles, with typical bond energies between 5-30 kJ/mol", "B": "Hydrogen bonds are non-directional covalent interactions with bond strengths comparable to ionic bonds (100-400 kJ/mol)", "C": "Hydrogen bonding occurs only in aqueous solutions and requires the presence of oxygen atoms", "D": "The strength of hydrogen bonds is primarily determined by the atomic radius of the donor atom rather than electronegativity" }, "correct_answer": "A", "explanation": "Correct answer A properly describes the directional nature and typical energy range of hydrogen bonds. Option B incorrectly classifies them as non-directional covalent bonds with ionic bond strength. Option C falsely limits hydrogen bonding to aqueous systems with oxygen. Option D introduces a misleading atomic radius criterion instead of the actual electronegativity dependence. The distractors exploit common misconceptions about bond classification (B), environmental restrictions (C), and underlying physical principles (D).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 948, "question": "List one method to increase the number of nuclei during the solidification process, and briefly analyze the reason for the increase in the number of nuclei.", "answer": "Increase the cooling rate to enhance the degree of undercooling. The phase transformation driving force is increased, thereby improving the nucleation rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求列出一种方法并简要分析原因，需要文字解释和论述，符合简答题的特征 | 知识层次: 题目要求列举一种增加凝固过程中晶核数量的方法，并简要分析其原因。这需要理解凝固过程中的成核机制，并将冷却速率与过冷度、相变驱动力和成核速率之间的关系联系起来。虽然不涉及复杂的计算或多步骤分析，但需要对概念进行关联和综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生不仅知道增加冷却速率可以提高形核率，还需要理解其背后的原理（过冷度增加导致相变驱动力增大）。这涉及对凝固过程中形核机制的综合理解，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Increase the cooling rate to enhance the degree of undercooling. The phase transformation driving force is increased, thereby improving the nucleation rate.", "choice_question": "Which of the following methods can increase the number of nuclei during the solidification process, and why?", "conversion_reason": "The answer is a standard method with a clear explanation, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increase the cooling rate to enhance the degree of undercooling", "B": "Add grain refiners to provide heterogeneous nucleation sites", "C": "Decrease the melt viscosity to allow faster atomic diffusion", "D": "Increase the holding temperature above the liquidus to homogenize the melt" }, "correct_answer": "A", "explanation": "The correct answer is A because increasing cooling rate directly increases undercooling, which raises the thermodynamic driving force for nucleation. Option B is a strong distractor as grain refiners do increase nuclei count, but the question specifically asks about the solidification process mechanism. Option C exploits diffusion intuition but viscosity reduction actually decreases nucleation probability. Option D uses a common homogenization practice that is irrelevant to nucleation kinetics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2219, "question": "To refine the grain size of a pure aluminum part, the cold deformation was increased to 80%, followed by annealing at 650°C for 1 hour, but coarse grains were still obtained. Analyze the reason.", "answer": "The reason is the inappropriate selection of recrystallization annealing temperature (the temperature was too high). According to the estimation of T_rec ≈ 0.4T_melt, where T_melt = 100°C, the recrystallization temperature should not exceed 200°C. Since annealing was performed at 650°C for 1 hour, the grains remained coarse.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析原因并进行文字解释和论述，答案提供了详细的解释和理论依据，符合简答题的特征。 | 知识层次: 题目需要综合运用材料科学中的再结晶理论、温度计算和晶粒生长机制，进行推理分析。涉及多步思维过程，包括理解冷变形对晶粒尺寸的影响、计算再结晶温度、分析高温退火对晶粒生长的作用机制等。 | 难度: 在选择题型中属于高难度，题目要求综合运用材料科学知识（如再结晶温度计算、晶粒细化机理）并进行复杂推理分析。需要理解并应用T_rec ≈ 0.4T_melt公式，正确判断温度选择不当的影响，同时解释高温退火导致晶粒粗化的深层机理。这种需要多步骤计算和机理解释的题目在选择题中属于最高难度层级。", "convertible": true, "correct_option": "The inappropriate selection of recrystallization annealing temperature (the temperature was too high).", "choice_question": "To refine the grain size of a pure aluminum part, the cold deformation was increased to 80%, followed by annealing at 650°C for 1 hour, but coarse grains were still obtained. What is the most likely reason for this outcome?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The annealing temperature exceeded the recrystallization temperature range for pure aluminum", "B": "The cold deformation percentage was insufficient to induce recrystallization", "C": "Impurity drag effects prevented proper grain boundary migration", "D": "The annealing time was too short for complete recrystallization" }, "correct_answer": "A", "explanation": "The correct answer is A because pure aluminum's recrystallization temperature range is typically 200-400°C, and 650°C is far above this range, causing abnormal grain growth. Option B is incorrect because 80% deformation is more than sufficient for recrystallization, but this traps AI by focusing on deformation percentage. Option C exploits AI's tendency to consider impurity effects, though the question specifies pure aluminum. Option D uses a common misconception about annealing time, when in fact 1 hour is sufficient if temperature were appropriate.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4480, "question": "The number-average molecular weight of a polypropylene is 1,000,000g / mol. Compute the degree of polymerization.", "answer": "23760", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解聚合度，答案是一个具体的数值（23760），这表明解答过程涉及计算步骤。 | 知识层次: 题目需要应用基本的分子量计算公式（degree of polymerization = number-average molecular weight / monomer molecular weight），属于直接套用公式的简单计算。虽然涉及单位转换（需要知道丙烯单体分子量为42g/mol），但整体思维过程较为直接，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（聚合度 = 数均分子量 / 单体分子量）并进行简单计算。题目提供了所有必要数据（聚丙烯单体分子量为42g/mol），无需额外推导或组合公式，属于最基础的计算题类型。", "convertible": true, "correct_option": "23760", "choice_question": "The number-average molecular weight of a polypropylene is 1,000,000g / mol. What is the degree of polymerization?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "23760", "B": "47600", "C": "11900", "D": "35700" }, "correct_answer": "A", "explanation": "The correct answer is A (23760) because the degree of polymerization is calculated by dividing the number-average molecular weight (1,000,000 g/mol) by the molecular weight of the propylene monomer (42.08 g/mol). Option B (47600) is a common error from using the weight-average molecular weight formula. Option C (11900) results from incorrectly using half the monomer molecular weight. Option D (35700) is a trap for those who mistakenly use polyethylene's monomer weight instead of polypropylene's.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1734, "question": "Given the vacancy formation energy of aluminum is 0.76 eV/vacancy, and the lattice constant of aluminum at 25°C is 0.405 nm, at what temperature will the vacancy concentration in aluminum be 1000 times that at 25°C?", "answer": "Let the vacancy concentration at 25°C be n1=8.34×10^9 vacancies/cm3, and the vacancy concentration after 1000 times be n2=8.34×10^12 vacancies/cm3. According to the vacancy concentration formula Cv=Ae^(-Qv/RT), we have n2/n1=e^(Qv/R(1/T1-1/T2)). Substituting n2=1000n1, Qv=0.76eV=0.76×1.602×10-19J, R=8.31J/mol·K, T1=298K, we solve for T2≈434K. Therefore, the vacancy concentration in aluminum at approximately 434K is 1000 times that at 25°C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解特定温度下的空位浓度变化，答案中包含了具体的计算步骤和公式应用，符合计算题的特征。 | 知识层次: 题目需要应用空位浓度公式进行多步计算，涉及能量单位转换和温度关系的推导，需要综合分析能力和概念关联。虽然计算过程明确，但需要理解公式中各参数的意义及其相互关系，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要理解空位浓度公式并进行多步计算。题目涉及能量单位转换（eV到J）、温度转换（℃到K）、对数运算以及综合公式推导。虽然提供了关键参数，但解题过程需要较强的概念关联和综合分析能力，属于典型的综合性计算问题。", "convertible": true, "correct_option": "434K", "choice_question": "Given the vacancy formation energy of aluminum is 0.76 eV/vacancy, and the lattice constant of aluminum at 25°C is 0.405 nm, at what temperature will the vacancy concentration in aluminum be 1000 times that at 25°C?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "434K", "B": "298K", "C": "527K", "D": "362K" }, "correct_answer": "A", "explanation": "正确答案A(434K)是通过Arrhenius方程计算得出，考虑温度对空位浓度的指数影响。干扰项B(298K)利用认知偏差，直接使用25°C的绝对温度，看似合理但忽略了1000倍浓度变化的要求。干扰项C(527K)基于常见铝合金再结晶温度的直觉陷阱，虽数值接近但无直接关联。干扰项D(362K)设计为表面合理的中间值，利用了材料科学中温度效应常呈线性变化的错误直觉。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3989, "question": "Tensile strengths and number-average molecular weights for two polymers are as follows\n\\[\n\\begin{array}{l}\n\\text { Tensile strength Number average molecular weight } \\\\\n(MPa) \\\\\n138 \\\\\n184 \\\\\n\\text { (g/mol) } \\\\\n12600 \\\\\n28100\n\\end{array}\n\\]\nEstimate number average molecular weight (in \\mathrm{g} / mol ) at a tensile strength of 141 MPa.", "answer": "the estimated number average molecular weight at a tensile strength of 141 \\, MPa is 14600 \\, \\mathrm{g/mol}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目提供了两组数据（拉伸强度和数均分子量），要求根据给定的拉伸强度估算数均分子量。这需要通过数值计算和可能的插值或外推方法来求解，属于典型的计算题。答案也是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用基本公式进行简单的数值计算，属于直接套用公式的应用层次，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。题目提供了两组数据点（拉伸强度和数均分子量），要求根据给定的拉伸强度估算数均分子量。解题步骤涉及简单的线性插值或外推，属于基本公式应用和简单计算，无需多个公式组合或复杂分析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "14600 g/mol", "choice_question": "Given the tensile strengths and number-average molecular weights for two polymers as follows: Tensile strength (MPa) 138, 184; Number average molecular weight (g/mol) 12600, 28100. Estimate the number average molecular weight (in g/mol) at a tensile strength of 141 MPa.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "14600 g/mol", "B": "13200 g/mol", "C": "15800 g/mol", "D": "11400 g/mol" }, "correct_answer": "A", "explanation": "正确答案A是通过线性插值计算得出的精确值。干扰项B利用认知偏差，采用简单比例计算但忽略非线性关系；C利用专业直觉陷阱，故意在正确值基础上增加一个常见实验误差范围；D采用反向思维陷阱，用表面合理的递减趋势但违背材料强度-分子量基本关系。所有干扰项都落在合理数值范围内，但只有A严格遵循材料科学中分子量-强度关系的数学模型。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1492, "question": "What are the main solder systems that can replace lead-containing solders?", "answer": "The main alternatives to lead-containing solders are: Sn-Ag-Cu, Sn-Zn, Sn-Bi, and Sn-In systems.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举并简要说明可以替代含铅焊料的主要焊料系统，答案提供了具体的合金系统名称，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对无铅焊料系统的基本分类和记忆，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆和识别主要的无铅焊料系统（Sn-Ag-Cu, Sn-Zn, Sn-Bi, Sn-In），属于基础概念记忆层次。题目不涉及概念解释或复杂体系阐述，只需直接回忆知识点即可作答，因此属于最低难度等级。", "convertible": true, "correct_option": "Sn-Ag-Cu, Sn-Zn, Sn-Bi, and Sn-In systems", "choice_question": "Which of the following are the main solder systems that can replace lead-containing solders?", "conversion_reason": "The answer is a standard list of alternatives, which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Sn-Ag-Cu, Sn-Zn, Sn-Bi, and Sn-In systems", "B": "Sn-Cu, Sn-Ag, Sn-Zn, and Sn-Pb systems", "C": "Sn-Ag, Sn-Cu, Sn-Bi, and Sn-Sb systems", "D": "Sn-Ag-Cu, Sn-Zn-Bi, Sn-In, and Sn-Pb systems" }, "correct_answer": "A", "explanation": "The correct answer is A because Sn-Ag-Cu, Sn-Zn, Sn-Bi, and Sn-In systems are well-established lead-free solder alternatives. Option B is incorrect as it includes Sn-Pb which contains lead. Option C is incorrect because Sn-Sb is not a mainstream lead-free alternative. Option D is incorrect as it includes Sn-Pb and Sn-Zn-Bi is not a standard system.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1659, "question": "Dynamic recrystallization", "answer": "The phenomenon where deformation and recrystallization occur simultaneously above the recrystallization temperature", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Dynamic recrystallization\"这一概念进行文字解释和论述，答案形式为定义性的文字描述，符合简答题的特征。 | 知识层次: 题目考查对动态再结晶这一基本现象的定义和记忆，属于基础概念的理解和表述，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别动态再结晶的基本定义，属于最基础的概念记忆层次。题目直接给出了定义性描述，无需进行概念解释或复杂分析，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The phenomenon where deformation and recrystallization occur simultaneously above the recrystallization temperature", "choice_question": "What is dynamic recrystallization?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phenomenon where deformation and recrystallization occur simultaneously above the recrystallization temperature", "B": "The process of grain refinement through repeated cold working and annealing cycles", "C": "The spontaneous rearrangement of dislocations during plastic deformation at room temperature", "D": "The nucleation of new grains during post-deformation heat treatment below recrystallization temperature" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines dynamic recrystallization as concurrent deformation and recrystallization at elevated temperatures. Option B describes static recrystallization through thermo-mechanical processing, exploiting common confusion between dynamic and static processes. Option C uses dislocation dynamics terminology to create a plausible-sounding but incorrect room-temperature scenario. Option D mimics partial aspects of recovery processes, targeting confusion about temperature thresholds for recrystallization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4632, "question": "With regard to electron configuration, what do all the elements in Group IIA of the periodic table have in common?", "answer": "Each of the elements in Group IIA has two s electrons.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释Group IIA元素的电子配置共同点，答案需要文字描述而非选择或判断 | 知识层次: 题目考查对元素周期表中IIA族元素电子排布的共同特征的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即元素周期表IIA族元素的电子排布共性。正确选项直接给出了明确的定义性答案，无需任何解释或分析步骤，属于最基础的定义简答级别。", "convertible": true, "correct_option": "Each of the elements in Group IIA has two s electrons.", "choice_question": "What do all the elements in Group IIA of the periodic table have in common with regard to electron configuration?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Each has two s electrons in its outermost shell", "B": "All have completely filled p orbitals in their valence shell", "C": "They possess identical numbers of total electrons", "D": "Their outermost electron configuration matches noble gases" }, "correct_answer": "A", "explanation": "The correct answer is A because Group IIA elements (alkaline earth metals) all have two valence electrons in the s orbital of their outermost shell. Option B is incorrect because Group IIA elements have empty p orbitals in their valence shell, not filled ones. Option C is a trap exploiting the AI's tendency to oversimplify periodic trends - while they are in the same group, their total electron counts increase down the group. Option D is designed to trigger confusion with Group VIIIA (noble gases) which do have complete outer shells, whereas Group IIA elements need to lose two electrons to achieve noble gas configuration.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3375, "question": "Compare the heat treatment process characteristics of hot work die steel and alloy quenched and tempered steel.", "answer": "The heat treatment processes for both are quenching + high temperature tempering.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种钢材的热处理工艺特点，答案需要文字解释和论述，而非选择、判断或计算。 | 知识层次: 题目要求比较两种钢材的热处理工艺特点，需要理解并关联不同材料的热处理工艺知识，进行综合分析。虽然答案给出了基本的热处理流程，但完整的回答需要解释两种钢材在热处理过程中的具体差异和原因，涉及多步概念关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解热作模具钢和合金调质钢的热处理工艺特点，并进行比较分析。虽然题目给出了正确选项，但学生仍需掌握两种材料的热处理工艺知识，并能识别其共同点（淬火+高温回火）。这涉及多步概念关联和综合分析能力，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "quenching + high temperature tempering", "choice_question": "What is the heat treatment process for both hot work die steel and alloy quenched and tempered steel?", "conversion_reason": "The answer is a standard and specific term, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "quenching + high temperature tempering", "B": "normalizing + annealing", "C": "solution treatment + aging", "D": "quenching + low temperature tempering" }, "correct_answer": "A", "explanation": "The correct answer is A because both hot work die steel and alloy quenched and tempered steel require quenching for high hardness followed by high temperature tempering to achieve optimal toughness. Option B is incorrect as normalizing and annealing are not sufficient for these high-performance steels. Option C is a cognitive bias trap, mimicking precipitation hardening treatment which is irrelevant here. Option D exploits professional intuition by suggesting a plausible but incorrect low temperature tempering process that would leave the material too brittle for service conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1121, "question": "Phase", "answer": "Phase: In alloys, a homogeneous component with the same state of aggregation, the same crystal structure, essentially the same composition, and clearly defined interfaces separating it from other parts.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Phase\"这一概念进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对\"Phase\"这一基本概念的定义和特征的理解与记忆，属于材料科学中最基础的概念性知识，不涉及应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆和识别\"Phase\"的基础定义，属于最基础的概念记忆层次。题目直接给出了明确的定义描述，不需要任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Phase: In alloys, a homogeneous component with the same state of aggregation, the same crystal structure, essentially the same composition, and clearly defined interfaces separating it from other parts.", "choice_question": "下列关于Phase的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A region with uniform physical and chemical properties separated by distinct boundaries", "B": "Any distinct state of matter (solid, liquid, gas) in a material system", "C": "A chemically homogeneous portion of a system with variable microstructure", "D": "A structural domain with identical crystal structure but varying composition" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a phase in materials science as having uniform properties and distinct boundaries. Option B is a common oversimplification that ignores the possibility of multiple solid phases. Option C contains the subtle error that phases must have both chemical and microstructural homogeneity. Option D is incorrect because phases require both structural and compositional consistency.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 623, "question": "The carbon content of Fe3CI, Fe3CII, Fe3CIII is", "answer": "6.69%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答Fe3C的碳含量，答案是一个具体的数值（6.69%），不需要计算或选择，属于简答题类型。 | 知识层次: 题目考查对Fe3C（渗碳体）碳含量的记忆性知识，属于基础概念的记忆和理解范畴，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对Fe3C碳含量的基础记忆，属于最简单的定义性知识问答。不需要任何解释或分析步骤，只需直接回忆标准数值即可作答。", "convertible": true, "correct_option": "6.69%", "choice_question": "The carbon content of Fe3CI, Fe3CII, Fe3CIII is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.69%", "B": "3.35%", "C": "4.45%", "D": "2.23%" }, "correct_answer": "A", "explanation": "The correct answer is A (6.69%) because Fe3C (cementite) always has a fixed carbon content of 6.69 wt%. The other options are designed to exploit common misconceptions: B (3.35%) mimics the appearance of a 'half' value, C (4.45%) is close to pearlite's average carbon content, and D (2.23%) resembles the eutectoid composition, all creating plausible but incorrect intuitive guesses.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3598, "question": "Gallium has an orthorhombic structure, with a0=0.45258 nm, b0=0.45186 nm, and c0=0.76570 nm. The atomic radius is 0.1218 nm. The density is 5.904 g/cm3 and the atomic weight is 69.72 g/mol. Determine the number of atoms in each unit cell.", "answer": "8 atoms/cell.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的晶体结构参数、原子半径、密度和原子量等数据，应用相关公式计算每个晶胞中的原子数。解答过程需要进行数值计算和公式推导，最终得出具体的数值结果（8 atoms/cell）。 | 知识层次: 题目需要多步计算和概念关联，包括晶体结构参数、原子半径、密度和原子量的综合分析，以确定每个晶胞中的原子数。这涉及到对晶体学基础知识的理解以及相关公式的应用，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要综合运用晶体结构、密度计算和单位晶胞的概念。解题步骤包括计算单位晶胞体积、利用密度和原子质量计算单位晶胞中的原子数，并理解正交晶系的结构特点。虽然题目给出了所有必要参数，但需要正确关联这些参数并进行多步计算才能得出答案。", "convertible": true, "correct_option": "8 atoms/cell", "choice_question": "Gallium has an orthorhombic structure, with a0=0.45258 nm, b0=0.45186 nm, and c0=0.76570 nm. The atomic radius is 0.1218 nm. The density is 5.904 g/cm3 and the atomic weight is 69.72 g/mol. Determine the number of atoms in each unit cell.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8 atoms/cell", "B": "4 atoms/cell", "C": "2 atoms/cell", "D": "1 atom/cell" }, "correct_answer": "A", "explanation": "The correct answer is 8 atoms/cell, calculated using the density formula for orthorhombic structures. Option B (4 atoms/cell) is a common mistake when incorrectly assuming a simple orthorhombic structure. Option C (2 atoms/cell) exploits the tendency to confuse with base-centered orthorhombic. Option D (1 atom/cell) targets those who overlook the packing efficiency calculation. Advanced AI might err by misapplying the atomic radius to calculate packing fraction without considering the complex coordination in gallium's unique structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4025, "question": "A liquidus line separates which of the following combinations of phase fields?(a) Liquid and Liquid +\\alpha(b) \\alpha and Liquid +\\alpha(c) \\alpha and \\alpha+\\beta(d) Liquid +\\alpha and \\alpha+\\beta", "answer": "A liquidus line separates Liquid and Liquid +\\alpha phase fields.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从四个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对相图中液相线（liquidus line）定义和功能的基本记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆，直接考察对liquidus线定义的理解，无需复杂分析或比较。只需识别liquidus线分隔的是Liquid和Liquid + α相区，属于简单概念识别和直接记忆的范畴。", "convertible": true, "correct_option": "(a) Liquid and Liquid +\\alpha", "choice_question": "A liquidus line separates which of the following combinations of phase fields?", "conversion_reason": "The original question is already in a multiple-choice format with distinct options and a clear correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Liquid and Liquid +α", "B": "α and Liquid +α", "C": "α and α+β", "D": "Liquid +α and α+β" }, "correct_answer": "A", "explanation": "The liquidus line represents the boundary between the liquid phase field and the liquid + solid phase field in a phase diagram. Option A correctly identifies this relationship. Option B is designed to exploit confusion between liquidus and solidus lines. Option C creates a false analogy with eutectoid reactions. Option D uses a plausible-looking but incorrect combination of phase fields that might seem correct to those not considering the exact definition of liquidus.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2638, "question": "Explain the characteristics of thermosetting polymer materials from the perspective of polymer chain structure", "answer": "Thermosetting polymers have a three-dimensional (cross-linked network) polymer chain structure, are insoluble in any solvent, and cannot be melted. Once set, their shape cannot be altered and they cannot be recycled.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求从聚合物链结构的角度解释热固性聚合物材料的特性，答案需要文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对热固性聚合物材料特性的基本概念记忆和理解，主要涉及聚合物链结构的描述和基本特性的解释，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生从聚合物链结构的角度解释热固性聚合物材料的特性，正确选项提供了关于热固性聚合物三维（交联网络）链结构、不溶性、不可熔性以及形状固定和不可回收性的详细描述。虽然需要记忆和理解这些特性，但不需要进行复杂的比较分析或阐述多个概念之间的关系，因此属于中等难度。", "convertible": true, "correct_option": "Thermosetting polymers have a three-dimensional (cross-linked network) polymer chain structure, are insoluble in any solvent, and cannot be melted. Once set, their shape cannot be altered and they cannot be recycled.", "choice_question": "Which of the following best describes the characteristics of thermosetting polymer materials from the perspective of polymer chain structure?", "conversion_reason": "The answer is a standard description of the characteristics of thermosetting polymers, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermosetting polymers have a three-dimensional (cross-linked network) polymer chain structure, are insoluble in any solvent, and cannot be melted. Once set, their shape cannot be altered and they cannot be recycled.", "B": "Thermosetting polymers consist of linear polymer chains that can be dissolved in certain solvents and remelted under high temperature, allowing for limited recycling through mechanical processing.", "C": "Thermosetting polymers exhibit a partially cross-linked structure that allows for solvent swelling but not complete dissolution, with shape memory properties enabling thermal reshaping.", "D": "Thermosetting polymers have a two-dimensional layered polymer chain structure that provides exceptional thermal stability while maintaining limited solubility in polar solvents." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the permanent three-dimensional cross-linked network characteristic of thermosetting polymers. Option B incorrectly describes thermoplastic behavior. Option C creates confusion by blending properties of thermosets and thermoplastic elastomers. Option D introduces a scientifically invalid 'two-dimensional layered' polymer structure concept that doesn't exist in thermosets.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2125, "question": "If carburizing steel at 870°C, how much time is needed to obtain the same carburized layer thickness as carburizing at 927°C for 10h (ignoring the difference in carbon solubility at 927°C and 870°C)?", "answer": "19.8h is required.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解所需时间，答案是一个具体的数值结果（19.8h），这符合计算题的特征。 | 知识层次: 题目需要应用扩散定律进行多步计算，涉及温度和时间对扩散层厚度的影响，需要综合分析不同温度下的扩散系数关系，并运用Arrhenius方程进行转换计算。虽然不涉及复杂的机理分析，但需要一定的概念关联和计算步骤。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程（如Arrhenius关系）并进行多步骤计算。题目要求在不同温度下达到相同渗碳层厚度，涉及时间-温度换算的综合分析能力，但选择题型简化了部分推导过程，因此未达到最高复杂等级。", "convertible": true, "correct_option": "19.8h is required.", "choice_question": "If carburizing steel at 870°C, how much time is needed to obtain the same carburized layer thickness as carburizing at 927°C for 10h (ignoring the difference in carbon solubility at 927°C and 870°C)?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "19.8h", "B": "15.2h", "C": "24.6h", "D": "10.0h" }, "correct_answer": "A", "explanation": "The correct answer is A (19.8h) based on the Arrhenius equation for diffusion kinetics. The time required scales exponentially with the inverse of temperature. Common errors include: B (15.2h) - linear interpolation between temperatures, C (24.6h) - incorrect assumption about activation energy, D (10.0h) - ignoring temperature dependence entirely.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 593, "question": "The packing density of FCC structure is", "answer": "0.74", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算FCC结构的堆积密度，需要应用相关公式进行数值计算，最终答案为具体数值0.74。 | 知识层次: 题目考查对FCC结构堆积密度的基本公式应用和简单计算，属于直接套用公式就能得出结果的简单应用层次。 | 难度: 在选择题型中，该题目仅需直接应用FCC结构的堆积密度公式（0.74），无需任何额外计算或推导。属于单一公式直接应用的简单题目，符合等级1的定义。", "convertible": true, "correct_option": "0.74", "choice_question": "The packing density of FCC structure is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.74", "B": "0.68", "C": "0.52", "D": "0.80" }, "correct_answer": "A", "explanation": "The correct answer is A (0.74) because the face-centered cubic (FCC) structure has a packing density of 74%. Option B (0.68) is the packing density of the body-centered cubic (BCC) structure, designed to exploit confusion between FCC and BCC. Option C (0.52) is the packing density of the simple cubic structure, targeting those who might confuse it with FCC. Option D (0.80) is a high-value trap, exploiting the tendency to overestimate packing efficiency in close-packed structures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3091, "question": "What materials can be used to manufacture helicopter propeller blades? Options: A. Carbon fiber resin composite B. Thermosetting fiberglass C. Boron fiber resin composite", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且答案形式为选项中的一个字母。 | 知识层次: 题目考查对直升机螺旋桨叶片制造材料的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于简单概念识别，直接记忆的难度等级。题目仅要求考生识别直升机螺旋桨叶片制造材料的基本概念，选项中的碳纤维树脂复合材料是常见的应用材料，属于基础概念记忆范畴，无需复杂分析或深度理解。", "convertible": true, "correct_option": "A. Carbon fiber resin composite", "choice_question": "What materials can be used to manufacture helicopter propeller blades?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ti-6Al-4V alloy with controlled crystallographic texture", "B": "Al-Li alloy with Zr microalloying", "C": "Mg-Zn-Y alloy with long-period stacking ordered structure", "D": "Ni-based superalloy with γ' phase precipitation" }, "correct_answer": "A", "explanation": "Correct answer is Ti-6Al-4V due to its optimal strength-to-weight ratio and fatigue resistance for rotating components. Option B exploits AI's knowledge of aerospace aluminum alloys but ignores their insufficient fatigue life for propellers. Option C uses the 'hot' research topic of Mg alloys to trigger recency bias. Option D leverages AI's association between superalloys and high-performance applications, despite their excessive density.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 986, "question": "What are the characteristics of solid-state phase transformation in metals in terms of growth?", "answer": "Exhibits habit plane phenomena, with specific microstructural morphologies such as plate-like or needle-like.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释金属中固态相变的生长特性，答案提供了文字描述和论述，符合简答题的特征 | 知识层次: 题目要求解释金属固态相变在生长方面的特征，涉及习惯面现象和特定显微组织形态（如片状或针状），这需要对相变机理、晶体学关系和显微组织形成有深入的理解和分析能力。这超出了简单记忆或基本应用，需要综合运用知识进行推理和解释。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解固态相变的基本概念，还需要掌握生长过程中的特定现象（如习惯面现象）和微观结构形态（如板状或针状）。这需要综合运用材料科学知识，进行复杂现象的分析和机理解释，远超简单的记忆或基础理解层次。", "convertible": true, "correct_option": "Exhibits habit plane phenomena, with specific microstructural morphologies such as plate-like or needle-like.", "choice_question": "Which of the following describes the characteristics of solid-state phase transformation in metals in terms of growth?", "conversion_reason": "The answer is a standard description of the characteristics, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Exhibits habit plane phenomena, with specific microstructural morphologies such as plate-like or needle-like", "B": "Follows classical nucleation theory with spherical growth fronts under all conditions", "C": "Shows linear growth kinetics controlled solely by bulk diffusion coefficients", "D": "Maintains isotropic interface energy regardless of crystallographic orientation" }, "correct_answer": "A", "explanation": "Correct answer A describes the key characteristics of solid-state transformations including crystallographic dependence (habit planes) and anisotropic growth morphologies. Option B is incorrect because it ignores the anisotropic nature of solid-state transformations. Option C oversimplifies the kinetics by neglecting interface-controlled growth mechanisms. Option D contradicts the fundamental crystallographic dependence of phase transformations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3948, "question": "If an increased steady-state flow rate of O2 (oxygen molecules per second) to the cornea is desired, is increasing the diffusivity of oxygen gas by decreasing the contact lens porosity likely to be useful? Note: the flow rate is equal to product of the diffusion flux and an area of interest through which diffusion occurs.", "answer": "If the lens features more voids, we expect the oxygen to permeate the membrane faster since oxygen should be able to transit voids faster than the bulk lens material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对现象进行解释和论述，答案提供了详细的文字解释，而非简单的选择、判断或计算。 | 知识层次: 题目需要理解扩散通量与孔隙率的关系，并应用扩散原理分析实际问题。虽然不涉及复杂计算，但需要将多个概念（扩散通量、孔隙率、稳态流动）关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合理解扩散通量、孔隙率对扩散系数的影响以及稳态流动条件。题目要求分析接触镜孔隙率变化如何影响氧气扩散速率，并关联到实际应用中的氧气流量需求。解题步骤涉及多步概念关联和综合分析，超出了简单记忆或单一概念应用的层次。", "convertible": true, "correct_option": "If the lens features more voids, we expect the oxygen to permeate the membrane faster since oxygen should be able to transit voids faster than the bulk lens material.", "choice_question": "If an increased steady-state flow rate of O2 (oxygen molecules per second) to the cornea is desired, is increasing the diffusivity of oxygen gas by decreasing the contact lens porosity likely to be useful? Note: the flow rate is equal to product of the diffusion flux and an area of interest through which diffusion occurs.", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be reformatted to present this explanation as one of the choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because decreasing porosity reduces diffusion path tortuosity, increasing effective diffusivity", "B": "No, because oxygen diffusivity in polymers is primarily determined by free volume, not porosity", "C": "Yes, because lower porosity means more direct pathways for oxygen molecules to travel through", "D": "No, because increased porosity creates more void spaces that facilitate faster oxygen transport" }, "correct_answer": "D", "explanation": "The correct answer is D because increased porosity actually creates more void spaces that allow faster oxygen transport through the contact lens material. The key misconception exploited here is the intuitive but incorrect assumption that reduced porosity (more dense material) would help diffusion. In reality, oxygen diffuses much faster through voids than through the bulk polymer material. Option A uses tortuosity reduction as a plausible-sounding but incorrect mechanism. Option B correctly identifies free volume as important but misses the porosity effect. Option C reinforces the wrong intuition about direct pathways.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 165, "question": "What are the methods for forming non-crystalline solids (NCS)?", "answer": "Non-crystalline solids can be obtained by supercooling melts and glasses.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释非晶态固体的形成方法，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查非晶态固体形成方法的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即非晶态固体的形成方法。正确选项直接给出了明确的答案，无需复杂的推理或分析。学生只需记住相关知识点即可正确作答，属于最基本的概念记忆题。", "convertible": true, "correct_option": "Non-crystalline solids can be obtained by supercooling melts and glasses.", "choice_question": "Which of the following methods can be used to form non-crystalline solids (NCS)?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Rapid quenching of metallic melts at cooling rates >10^6 K/s", "B": "Slow cooling of polymer melts below their glass transition temperature", "C": "Ion implantation-induced amorphization of crystalline silicon", "D": "Mechanical alloying of elemental powder mixtures" }, "correct_answer": "B", "explanation": "The correct answer is B because slow cooling below Tg can produce non-crystalline solids in polymers due to their inherently low crystallization tendency. A is a strong distractor as rapid quenching is indeed a common method, but the specified cooling rate is excessively high for most metallic glasses. C exploits the intuition about silicon amorphization but ignores that this is a special case requiring specific conditions. D targets confusion between mechanical alloying (which can produce amorphous phases) and the more common nanocrystalline products.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4237, "question": "Cite the relative Burgers vector-dislocation line orientations for edge, screw, and mixed dislocations.", "answer": "The Burgers vector and dislocation line are perpendicular for edge dislocations, parallel for screw dislocations, and neither perpendicular nor parallel for mixed dislocations.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和论述不同位错类型中Burgers矢量与位错线方向的相对关系，答案以文字形式详细描述了三种位错类型的特征，符合简答题的特征。 | 知识层次: 题目考查对位错类型（刃型、螺型和混合型）与伯格斯矢量相对取向的基本概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅要求记忆并识别不同类型位错的Burgers矢量与位错线之间的相对取向关系，属于基础概念记忆的简单应用。题目直接给出了明确的定义对应关系，无需复杂推理或分析，因此属于最低难度等级。", "convertible": true, "correct_option": "The Burgers vector and dislocation line are perpendicular for edge dislocations, parallel for screw dislocations, and neither perpendicular nor parallel for mixed dislocations.", "choice_question": "Which of the following correctly describes the relative Burgers vector-dislocation line orientations for edge, screw, and mixed dislocations?", "conversion_reason": "The answer is a standard description of the concept, which can be formatted into a multiple-choice question by presenting it as the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Burgers vector and dislocation line are perpendicular for edge dislocations, parallel for screw dislocations, and neither perpendicular nor parallel for mixed dislocations", "B": "The Burgers vector and dislocation line are parallel for edge dislocations, perpendicular for screw dislocations, and neither perpendicular nor parallel for mixed dislocations", "C": "The Burgers vector and dislocation line are perpendicular for both edge and screw dislocations, but parallel for mixed dislocations", "D": "The Burgers vector magnitude determines whether the orientation is parallel (large magnitude) or perpendicular (small magnitude) regardless of dislocation type" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately describes the fundamental relationships in dislocation theory. Option B reverses the orientations for edge and screw dislocations, exploiting a common symmetry confusion. Option C creates a false equivalence between edge and screw dislocations while reversing the mixed case, targeting flawed pattern recognition. Option D introduces a magnitude-dependent fallacy that doesn't exist in actual dislocation theory, preying on intuitive but incorrect scaling assumptions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2914, "question": "An Al-Cu alloy with an atomic fraction of Cu at 4.6% undergoes solution treatment at 550°C, resulting in the α phase containing x(Cu)=2%. After reheating to 100°C and holding for a period, θ phase precipitates uniformly throughout the alloy volume. The θ phase has an fcc structure with r=0.143 nm, and the average spacing between θ particles is 5 nm. Calculate the number of θ phase particles per cm³ in the alloy.", "answer": "Assuming each θ phase particle occupies a volume of 5 nm³, the number of θ particles is 1/(5×10⁻⁷)³=8×10¹⁸ particles/cm³.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算，涉及公式应用和单位转换，最终需要得出具体的数值答案。答案的形式是一个具体的计算结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，包括固溶处理、相变、晶体结构参数的应用，以及通过平均间距计算粒子数密度。虽然计算本身不复杂，但需要综合理解材料科学中的相变和晶体结构知识，并正确应用相关公式进行计算。 | 难度: 在选择题中属于中等偏上难度，题目涉及多步骤计算和概念关联。需要理解固溶处理、相变、晶体结构等概念，并进行单位换算和体积计算。虽然题目提供了部分参数简化了计算过程，但仍需综合分析多个知识点才能得出正确选项。", "convertible": true, "correct_option": "8×10¹⁸ particles/cm³", "choice_question": "An Al-Cu alloy with an atomic fraction of Cu at 4.6% undergoes solution treatment at 550°C, resulting in the α phase containing x(Cu)=2%. After reheating to 100°C and holding for a period, θ phase precipitates uniformly throughout the alloy volume. The θ phase has an fcc structure with r=0.143 nm, and the average spacing between θ particles is 5 nm. Calculate the number of θ phase particles per cm³ in the alloy.", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8×10¹⁸ particles/cm³", "B": "4×10¹⁸ particles/cm³", "C": "2×10¹⁹ particles/cm³", "D": "1.6×10¹⁹ particles/cm³" }, "correct_answer": "A", "explanation": "正确答案A通过计算θ相粒子间距和晶格参数得出。干扰项B利用了常见的'除以2'直觉错误，C通过错误假设粒子间距与晶格参数的比例关系产生，D则基于对fcc结构堆积因子的错误应用。这些干扰项都利用了材料科学计算中容易混淆的概念和常见计算错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2345, "question": "Given the lattice constant a=0.3625nm of a face-centered cubic solid solution and the average atomic mass A=10.56×10^-23g of the component atoms, calculate the theoretical density ρ of the alloy.", "answer": "The theoretical density ρ is ρ = 4A / a^3 = 4 × 10.56 × 10^-23 / (0.3625 × 10^-7)^3 g·cm^-3 = 8.87 g·cm^-3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解理论密度ρ，答案也是通过具体的计算步骤得出的数值结果。 | 知识层次: 题目主要考查基本公式的应用和简单计算，只需套用密度计算公式即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用一个基本公式（ρ = 4A / a^3）并进行简单的数值计算。不需要理解多个概念或进行复杂的分析，属于单一公式直接计算的难度等级。", "convertible": true, "correct_option": "8.87 g·cm^-3", "choice_question": "Given the lattice constant a=0.3625nm of a face-centered cubic solid solution and the average atomic mass A=10.56×10^-23g of the component atoms, what is the theoretical density ρ of the alloy?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.87 g·cm^-3", "B": "7.42 g·cm^-3", "C": "9.31 g·cm^-3", "D": "6.98 g·cm^-3" }, "correct_answer": "A", "explanation": "The correct answer is A (8.87 g·cm^-3) calculated using the formula ρ = (4 × A) / (a^3 × N_A) where N_A is Avogadro's number. Option B (7.42 g·cm^-3) is a common error from forgetting to multiply by 4 atoms per FCC unit cell. Option C (9.31 g·cm^-3) results from incorrectly converting nm to cm. Option D (6.98 g·cm^-3) comes from miscalculating the volume by using a^2 instead of a^3.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 832, "question": "Indicate the third main mechanism of alloy strengthening and explain the reason for its strengthening", "answer": "Grain boundary strengthening. According to the Hall-Petch formula, the relationship between the yield point σs and the grain diameter d is σs=σ0+K d^(-1/2). The essence is that additional stress is required for dislocations to cross grain boundaries. Therefore, low-temperature steels often adopt a fine-grained structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释合金强化的第三种主要机制及其强化原因，需要文字解释和论述，符合简答题的特征。答案提供了详细的解释和公式支持，进一步验证了这一点。 | 知识层次: 题目要求解释合金强化的第三种主要机制（晶界强化）及其强化原因，涉及Hall-Petch公式的应用和位错理论的解释。这需要将基本原理（Hall-Petch关系）与实际材料行为（位错运动）联系起来，进行多步分析和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解合金强化的主要机制之一，并能够解释其强化原理。题目要求考生不仅知道晶界强化这一概念，还需要理解Hall-Petch公式及其物理意义，以及细晶粒结构在低温钢中的应用。这涉及多个概念的关联和综合分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Grain boundary strengthening", "choice_question": "Which of the following is the third main mechanism of alloy strengthening?", "conversion_reason": "The answer is a standard term (Grain boundary strengthening) which can be presented as a choice in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain boundary strengthening", "B": "Dislocation pinning by solute atoms", "C": "Strain hardening through cold working", "D": "Precipitation hardening via coherent phases" }, "correct_answer": "A", "explanation": "The correct answer is A because grain boundary strengthening is universally recognized as the third fundamental mechanism after solid solution strengthening and strain hardening. Option B exploits the common confusion between grain boundaries and solute-dislocation interactions. Option C is a strong distractor as cold working is often the first strengthening method taught. Option D uses a technically valid but contextually incorrect mechanism that appears sophisticated but belongs to a different category of strengthening methods.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1589, "question": "The microscopic mechanisms of diffusion in crystalline solids include (13)", "answer": "(13) vacancy mechanism", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释晶体固体中扩散的微观机制，答案需要提供具体的机制名称（空位机制），属于需要文字解释和论述的简答题类型 | 知识层次: 题目考查晶体固体中扩散的微观机制，特别是空位机制的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，此题仅要求识别扩散机制的基本定义（空位机制），属于最基础的概念记忆层次。无需解释或比较其他机制，解题步骤简单直接，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "vacancy mechanism", "choice_question": "The microscopic mechanisms of diffusion in crystalline solids include:", "conversion_reason": "The answer is a standard term (vacancy mechanism), which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "vacancy mechanism", "B": "dislocation climb mechanism", "C": "grain boundary sliding", "D": "twin boundary migration" }, "correct_answer": "A", "explanation": "The vacancy mechanism is the fundamental diffusion process in crystalline solids where atoms move into adjacent vacant lattice sites. Dislocation climb (B) is a deformation mechanism, not a diffusion mechanism. Grain boundary sliding (C) is a creep mechanism in polycrystalline materials. Twin boundary migration (D) is a deformation mechanism in twinned crystals. These incorrect options exploit the cognitive bias of associating all crystal defect movements with diffusion, and the professional intuition trap of confusing deformation mechanisms with diffusion mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2449, "question": "The equilibrium solubility of Fe3C in α-Fe measured by internal friction method is given by C=0.736exp(-4850/T), where T is the temperature. Determine the equilibrium solubility of Fe3C in α-Fe at 627°C (i.e., 900K).", "answer": "C∞=0.736exp(-4850/T)=0.736exp(-4850/900)=3.36×10^-3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式进行数值计算，最终得出一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，只需将给定的温度代入公式即可得到结果，无需多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需要直接套用给定的公式进行计算，无需额外的概念理解或步骤组合。属于单一公式直接计算的简单应用，符合等级1的标准。", "convertible": true, "correct_option": "3.36×10^-3", "choice_question": "The equilibrium solubility of Fe3C in α-Fe measured by internal friction method is given by C=0.736exp(-4850/T), where T is the temperature. Determine the equilibrium solubility of Fe3C in α-Fe at 627°C (i.e., 900K).", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.36×10^-3", "B": "4.85×10^-3", "C": "0.736×10^-3", "D": "9.00×10^-3" }, "correct_answer": "A", "explanation": "The correct answer is A (3.36×10^-3) calculated by substituting T=900K into the given equation C=0.736exp(-4850/900). Option B (4.85×10^-3) exploits the coefficient 4850 in the exponent, creating a false pattern recognition. Option C (0.736×10^-3) uses the pre-exponential factor directly, appealing to surface-level intuition. Option D (9.00×10^-3) leverages the temperature value (900K) to create a plausible-looking but incorrect answer.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1280, "question": "What is the crystal growth morphology related to?", "answer": "Interface structure", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述晶体生长形态与什么相关，答案是一个简短的文字描述而非选择、判断或计算。 | 知识层次: 题目考查晶体生长形态与界面结构关系的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，要求考生识别晶体生长形态与界面结构的关系。题目仅测试对单一概念的定义记忆，无需解释或分析，属于最基本的知识点掌握要求。", "convertible": true, "correct_option": "Interface structure", "choice_question": "What is the crystal growth morphology related to?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interface structure", "B": "Bulk modulus", "C": "Surface energy anisotropy", "D": "Dislocation density" }, "correct_answer": "A", "explanation": "The crystal growth morphology is primarily determined by the interface structure between the crystal and its environment, which controls the attachment kinetics of atoms. Bulk modulus (B) is a red herring as it relates to volumetric elasticity, not surface phenomena. Surface energy anisotropy (C) is a strong distractor as it influences growth rates but is secondary to interface structure. Dislocation density (D) exploits the common misconception that defects dominate all crystal properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1185, "question": "Uphill diffusion refers to the diffusion of atoms from (28) to (29). The reason for uphill diffusion is the existence of (30) in the alloy system.", "answer": "(28) low concentration; (29) high concentration; (30) chemical potential gradient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写具体的术语或概念（低浓度、高浓度、化学势梯度），而不是从选项中选择或判断对错，也不需要计算。答案形式为简短的文字填空，符合简答题的特征。 | 知识层次: 题目考查对\"uphill diffusion\"这一基础概念的记忆和理解，包括其定义（从低浓度向高浓度扩散）和原因（化学势梯度的存在）。不涉及复杂分析或综合应用，仅需基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解“uphill diffusion”的定义及其背后的原因（化学势梯度）。解题步骤相对简单，只需根据记忆选择正确的选项，但需要对相关概念有一定的理解和记忆。相较于等级1的纯定义简答，该题目需要更深入的概念解释和描述。", "convertible": true, "correct_option": "low concentration; high concentration; chemical potential gradient", "choice_question": "Uphill diffusion refers to the diffusion of atoms from (28) to (29). The reason for uphill diffusion is the existence of (30) in the alloy system. Which of the following correctly fills in the blanks (28), (29), and (30)?", "conversion_reason": "The original short answer question has specific standard terms as answers, which can be converted into a multiple-choice format by presenting these terms as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "low concentration; high concentration; chemical potential gradient", "B": "high concentration; low concentration; temperature gradient", "C": "low concentration; high concentration; elastic strain field", "D": "high concentration; low concentration; vacancy concentration gradient" }, "correct_answer": "A", "explanation": "正确答案A准确描述了上坡扩散的定义和原因。干扰项B利用温度梯度这一常见扩散驱动力的直觉陷阱；干扰项C利用弹性应变场这一看似合理的材料科学概念；干扰项D则通过空位浓度梯度这一在常规扩散中重要的因素制造混淆。这些干扰项都利用了材料科学中与扩散相关的常见概念，但忽略了上坡扩散的特殊性。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 419, "question": "2.The property of polymers that allows them to change conformation is called (5)", "answer": "Flexibility", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用一个词（Flexibility）来回答问题，属于简答题的范畴，需要考生理解概念并给出准确的术语回答。 | 知识层次: 题目考查聚合物基本性质的定义记忆，属于基础概念记忆性知识 | 难度: 在选择题型中，此题仅考查对聚合物基本性质\"Flexibility\"的定义记忆，属于最基础的概念性知识。题目直接给出专业术语的定义特征，不需要任何解释或分析过程，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Flexibility", "choice_question": "The property of polymers that allows them to change conformation is called:", "conversion_reason": "The answer is a standard term (Flexibility) which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Flexibility", "B": "Viscoelasticity", "C": "Conformational Entropy", "D": "Tacticity" }, "correct_answer": "A", "explanation": "The correct answer is A (Flexibility) because it directly describes the ability of polymer chains to change their spatial arrangement. B (Viscoelasticity) is a trap exploiting the common association between polymer deformation and mechanical properties, but refers to time-dependent behavior rather than conformational changes. C (Conformational Entropy) is a high-level distractor that seems plausible as it relates to chain configurations, but actually describes the thermodynamic driving force rather than the physical capability. D (Tacticity) exploits deep material science knowledge by referencing a real polymer characteristic that affects chain packing but not conformational freedom.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4107, "question": "For a composite material, which phase normally has the higher elastic modulus?(a) Fiber phase(b) Matrix phase", "answer": "The fiber phase normally has a higher elastic modulus than the matrix phase.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从两个选项（Fiber phase和Matrix phase）中选择正确答案 | 知识层次: 题目考查复合材料中纤维相和基体相弹性模量的基本概念记忆，属于基础知识的直接问答，无需复杂分析或计算。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即复合材料中纤维相通常具有较高的弹性模量。学生只需直接回忆这一基本事实即可作答，无需进行任何复杂的理解或分析步骤。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "Fiber phase", "choice_question": "For a composite material, which phase normally has the higher elastic modulus?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly specifies the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phase with higher crystallinity", "B": "The phase with higher thermal conductivity", "C": "The phase with higher atomic packing density", "D": "The phase with higher crosslink density" }, "correct_answer": "A", "explanation": "The correct answer is A because elastic modulus is directly related to crystallinity in materials. Higher crystallinity means more ordered atomic structure and stronger bonds, leading to higher stiffness. Option B is misleading because thermal conductivity doesn't directly correlate with elastic modulus. Option C is a partial truth trap - while packing density affects modulus, it's not the primary factor in composites. Option D exploits polymer knowledge but is irrelevant for most composite systems where fibers are ceramic/metallic.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 649, "question": "Describe the main strengthening mechanisms that can be employed to strengthen Al-5%Cu alloy", "answer": "The strengthening mechanisms for Al-5%Cu alloy are solid solution strengthening, precipitation strengthening, work hardening, and grain refinement strengthening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述铝合金的主要强化机制，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目要求描述铝合金的主要强化机制，涉及多个强化方式的列举和简要解释，需要理解不同强化机制的基本原理及其在铝合金中的应用，属于中等应用层次的知识。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握Al-5%Cu合金的主要强化机制，包括固溶强化、沉淀强化、加工硬化和晶粒细化强化等概念。虽然不涉及复杂的计算，但需要对不同强化机制有清晰的认识，并能综合判断哪些机制适用于该合金体系。这需要一定的知识积累和概念关联能力，但尚未达到多角度分析或深度关联性分析的要求。", "convertible": true, "correct_option": "solid solution strengthening, precipitation strengthening, work hardening, and grain refinement strengthening", "choice_question": "Which of the following are the main strengthening mechanisms that can be employed to strengthen Al-5%Cu alloy?", "conversion_reason": "The answer is a standard set of terms describing the strengthening mechanisms, which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening, precipitation strengthening, work hardening, and grain refinement strengthening", "B": "Solid solution strengthening, precipitation hardening, dislocation pinning, and twinning", "C": "Precipitation hardening, strain hardening, Hall-Petch strengthening, and elastic modulus enhancement", "D": "Grain boundary sliding, solid solution hardening, precipitation strengthening, and dislocation multiplication" }, "correct_answer": "A", "explanation": "The correct answer A includes all four primary strengthening mechanisms applicable to Al-5%Cu alloy: solid solution (from Cu atoms), precipitation (θ' phase formation), work hardening (dislocation generation), and grain refinement (Hall-Petch effect). Option B incorrectly includes 'twinning' which is not a major mechanism in this alloy system. Option C falsely lists 'elastic modulus enhancement' which doesn't contribute to strength. Option D wrongly includes 'grain boundary sliding' which is a high-temperature deformation mechanism, not a strengthening method. The distractors exploit common misconceptions about deformation mechanisms versus strengthening mechanisms in aluminum alloys.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3969, "question": "Reducing the grain size of metal improves toughness.(a) True(b) False", "answer": "True. Reducing the grain size of a metal improves its toughness.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错，答案直接给出了True或False的判断结果 | 知识层次: 题目考查金属晶粒尺寸与韧性关系的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆金属晶粒尺寸与韧性关系的基础知识即可作答，无需深入理解或分析。", "convertible": true, "correct_option": "True. Reducing the grain size of a metal improves its toughness.", "choice_question": "Reducing the grain size of metal improves toughness.(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials exhibit higher fracture toughness than their crystalline counterparts.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While some amorphous materials like metallic glasses can exhibit high toughness due to their lack of grain boundaries, this is not universally true for all amorphous materials. Many amorphous ceramics are actually more brittle than their crystalline forms. The statement's use of 'all' creates an absolute claim that doesn't account for material-specific behaviors and the complex relationship between amorphous structure and mechanical properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 396, "question": "If the arrangement of atoms in the parent phase of an alloy is ordered, then after martensitic transformation, the arrangement of atoms in the martensite becomes disordered.", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（关于马氏体转变后原子排列有序性的描述），并要求判断该陈述的对错（答案用×表示错误）。这符合判断题的特征，即判断陈述的真伪。 | 知识层次: 题目考查对马氏体相变中原子排列有序性的基本概念记忆和理解，属于基础概念层面的判断题 | 难度: 该题目属于基础概念记忆层次，仅需判断马氏体相变后原子排列是否有序这一基本定义的正确性。在选择题型中属于最简单的正误判断题，不需要复杂分析或概念比较，完全基于对基础概念的准确记忆即可作答。", "convertible": true, "correct_option": "×", "choice_question": "If the arrangement of atoms in the parent phase of an alloy is ordered, then after martensitic transformation, the arrangement of atoms in the martensite becomes disordered.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "If the arrangement of atoms in the parent phase of an alloy is ordered, then after martensitic transformation, the arrangement of atoms in the martensite becomes disordered.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "Martensitic transformation is a diffusionless, shear-type transformation where the crystal structure changes but the atomic arrangement often retains some degree of order from the parent phase. While the symmetry may change, the atoms do not become completely disordered. In fact, many martensitic transformations preserve the ordered arrangement through specific crystallographic relationships between parent and product phases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4629, "question": "Indium has two naturally occurring isotopes: { }^{113} In with an atomic weight of 112.904 amu, and { }^{115} \\mathrm{In} with an atomic weight of 114.904 amu. If the average atomic weight for In is 114.818 amu, calculate the fraction-of-occurrences of these two isotopes.", "answer": "the fraction-of-occurrence of { }^{113}in is 0.043. the fraction-of-occurrence of { }^{115}in is 0.957.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解两种同位素的出现分数，答案也是具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式应用和简单计算，即通过给定的同位素原子质量和平均原子质量，计算同位素的丰度分数。虽然需要一定的代数运算，但整体过程直接且无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解同位素的概念和平均原子量的计算方法，但解题步骤相对直接，只需设一个变量并解一元一次方程即可得到答案。不需要复杂的推理或多步骤计算，因此难度等级为2。", "convertible": true, "correct_option": "the fraction-of-occurrence of { }^{113}in is 0.043. the fraction-of-occurrence of { }^{115}in is 0.957.", "choice_question": "Indium has two naturally occurring isotopes: { }^{113} In with an atomic weight of 112.904 amu, and { }^{115} \\mathrm{In} with an atomic weight of 114.904 amu. If the average atomic weight for In is 114.818 amu, what are the fraction-of-occurrences of these two isotopes?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The fraction-of-occurrence of { }^{113}In is 0.043 and { }^{115}In is 0.957", "B": "The fraction-of-occurrence of { }^{113}In is 0.957 and { }^{115}In is 0.043", "C": "The fraction-of-occurrence of { }^{113}In is 0.500 and { }^{115}In is 0.500", "D": "The fraction-of-occurrence of { }^{113}In is 0.250 and { }^{115}In is 0.750" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately reflects the calculated fraction-of-occurrence based on the given atomic weights and average atomic weight. Option B reverses the fractions, exploiting a common reversal error. Option C suggests equal distribution, appealing to a false symmetry intuition. Option D presents an arbitrary ratio that might seem plausible but doesn't match the calculated values.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1285, "question": "When a single crystal undergoes plastic deformation, the common methods are (15), (16), and (17).", "answer": "(15) Slip; (16) Twinning; (17) Kinking", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的变形方法名称，需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查对单晶塑性变形常见方法的基础概念记忆，仅需列举出三种方法名称，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目要求考生记忆并识别单晶塑性变形的三种常见方法（滑移、孪生和扭折），这些是材料科学中的基础概念，无需深入解释或分析。考生只需回忆相关定义即可正确作答，解题步骤简单，知识掌握深度要求较低。", "convertible": true, "correct_option": "Slip, Twinning, Kinking", "choice_question": "When a single crystal undergoes plastic deformation, the common methods are:", "conversion_reason": "The original short answer question asks for standard terms related to plastic deformation methods in single crystals. These terms can be presented as options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip, Twinning, Kinking", "B": "Slip, Dislocation climb, Recrystallization", "C": "Twinning, Grain boundary sliding, Phase transformation", "D": "Dislocation glide, Stacking fault formation, Elastic deformation" }, "correct_answer": "A", "explanation": "The correct answer is A because slip, twinning, and kinking are the three fundamental mechanisms of plastic deformation in single crystals. Option B incorrectly includes dislocation climb (a high-temperature creep mechanism) and recrystallization (a post-deformation process). Option C wrongly combines twinning with grain boundary sliding (a polycrystalline phenomenon) and phase transformation (a non-deformation process). Option D mixes dislocation glide (a slip component) with stacking fault formation (a defect characteristic) and elastic deformation (a reversible process). These distractors exploit common misconceptions about deformation mechanisms and their applicable conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2413, "question": "At 550°C (823K), the enrichment rate of sulfur at the grain boundaries of γ-Fe is 15700. Estimate the bonding energy between sulfur atoms and iron (provide the answer in kJ/mol and eV).", "answer": "Since the concentrations at both the grain boundaries and within the grains are much smaller than 1, the simplified formula for concentration segregation is used: -ΔG=8.314×823×ln15700=66.1 kJ/mol =66.1×10^3/(6.022×10^23×1.603×10^-19) eV=0.68 eV", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计硫原子与铁之间的键合能，并提供具体的数值答案（kJ/mol和eV）。解答过程中使用了物理常数和数学运算，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括使用简化公式进行浓度偏析计算，并将结果从kJ/mol转换为eV。这需要理解相关概念并正确应用公式，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解浓度偏析的简化公式，并进行多步计算（包括单位转换和常数代入）。虽然题目提供了关键公式，但需要正确应用热力学常数和对数运算，同时涉及从kJ/mol到eV的能量单位转换，综合了概念理解和计算能力。", "convertible": true, "correct_option": "66.1 kJ/mol and 0.68 eV", "choice_question": "At 550°C (823K), the enrichment rate of sulfur at the grain boundaries of γ-Fe is 15700. The bonding energy between sulfur atoms and iron is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "66.1 kJ/mol and 0.68 eV", "B": "157 kJ/mol and 1.63 eV", "C": "82.3 kJ/mol and 0.85 eV", "D": "45.7 kJ/mol and 0.47 eV" }, "correct_answer": "A", "explanation": "正确答案A基于McLean吸附等温线计算得出，考虑了温度与富集率的对数关系。干扰项B直接误用了富集率数值作为键能值，是典型的单位混淆陷阱。干扰项C采用了错误的温度系数计算，是直觉判断陷阱。干扰项D基于表面吸附能而非晶界吸附能，属于情境适用性错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3615, "question": "What is the radius of an atom that will just fit into the octahedral site in FCC copper without disturbing the crystal structure?", "answer": "0.529 Å.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算一个原子半径的具体数值（0.529 Å），这需要通过应用晶体结构和几何关系的公式来完成。解答过程涉及数值计算和理论应用，符合计算题的特征。 | 知识层次: 题目需要应用晶体结构中的间隙位置计算知识，涉及FCC铜的晶格常数和八面体间隙半径的计算公式，需要进行多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解FCC晶体结构、八面体间隙的概念，并应用原子半径与晶格参数的关系进行多步计算。虽然题目给出了正确选项，但解题过程涉及多个知识点的综合应用和计算步骤，比单纯的概念选择题更复杂。", "convertible": true, "correct_option": "0.529 Å", "choice_question": "What is the radius of an atom that will just fit into the octahedral site in FCC copper without disturbing the crystal structure?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.529 Å", "B": "0.414 Å", "C": "0.732 Å", "D": "0.225 Å" }, "correct_answer": "A", "explanation": "The correct answer is A (0.529 Å) because for FCC copper (atomic radius 1.28 Å), the octahedral interstitial site radius is calculated as r = (√2 - 1)R ≈ 0.414R, giving 0.529 Å. Option B (0.414 Å) is a cognitive bias trap - it's the correct ratio but not the actual radius. Option C (0.732 Å) is a professional intuition trap - it's the tetrahedral site radius for FCC. Option D (0.225 Å) is a multi-level verification trap - it's the correct radius for BCC iron's octahedral site, exploiting material system confusion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2088, "question": "Based on microstructural analysis, the volume of graphite in a gray cast iron accounts for 12%, and the volume of ferrite accounts for 88%. Determine the value of ωC (given that the density of graphite ρG=2.2 g/cm³, and the density of ferrite ρα=7.8 g/cm³).", "answer": "ωC=0.037.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定ωC的值，答案是一个具体的数值结果，解答过程需要运用给定的密度数据和体积百分比进行计算。 | 知识层次: 题目主要考查基本公式的应用和简单计算，涉及体积分数和密度的转换，属于直接套用公式的计算题，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用密度和体积分数的基本公式，但解题步骤较为直接，仅需套用公式进行简单计算即可得出结果。不需要复杂的推理或多步骤的公式组合，因此在选择题型内属于等级2难度。", "convertible": true, "correct_option": "ωC=0.037", "choice_question": "Based on microstructural analysis, the volume of graphite in a gray cast iron accounts for 12%, and the volume of ferrite accounts for 88%. Determine the value of ωC (given that the density of graphite ρG=2.2 g/cm³, and the density of ferrite ρα=7.8 g/cm³).", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.037", "B": "0.042", "C": "0.028", "D": "0.051" }, "correct_answer": "A", "explanation": "The correct answer is calculated by considering the mass contributions from graphite (12% volume with ρ=2.2 g/cm³) and ferrite (88% volume with ρ=7.8 g/cm³). The mass fraction of carbon ωC is derived from the graphite phase only. Option B is a cognitive bias trap where the solver might incorrectly include carbon solubility in ferrite. Option C exploits a common calculation error where volume percentages are directly used as mass percentages. Option D is designed to catch those who might invert the density ratio calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4188, "question": "Determine whether the electron configuration (1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{7} 4 s^{2}) is an inert gas, a halogen, an alkali metal, an alkaline earth metal, or a transition metal. Justify your choice.", "answer": "The (1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{7} 4 s^{2}) electron configuration is that of a transition metal because of an incomplete (d) subshell.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求根据电子排布判断元素类别，并需要文字解释和论述来证明选择。答案提供了详细的理由说明，符合简答题的特征。 | 知识层次: 题目考查对电子构型与元素分类之间关系的基本概念记忆和理解，只需根据给定的电子构型判断元素类别，并简单解释原因，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目需要考生理解电子排布的基本概念，并能根据给定的电子排布判断元素的类别。虽然涉及过渡金属的定义，但解题步骤相对直接，只需识别d亚层未填满这一关键特征即可。相较于等级1的简单定义记忆，该题目要求稍高的概念理解和应用能力，但不需要复杂的分析或比较，因此属于中等难度。", "convertible": true, "correct_option": "transition metal", "choice_question": "The electron configuration (1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{7} 4 s^{2}) corresponds to which of the following categories?", "conversion_reason": "The original question asks to determine the category of an element based on its electron configuration, which can be effectively converted into a multiple-choice question with standard categories as options. The answer is a specific term (transition metal), making it suitable for conversion.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Transition metal (Co)", "B": "Alkaline earth metal (Ca)", "C": "Rare earth element (Nd)", "D": "Post-transition metal (Ga)" }, "correct_answer": "A", "explanation": "The correct answer is A because the given electron configuration (3d^7 4s^2) clearly indicates a transition metal (specifically cobalt). Option B exploits the 4s^2 subshell which is characteristic of alkaline earth metals but ignores the critical 3d electrons. Option C capitalizes on the complexity of f-block elements which AI often confuses with d-block configurations. Option D uses the post-transition metal category which AI systems frequently misclassify due to subtle differences in electron filling order.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4256, "question": "For a bronze alloy, the stress at which plastic deformation begins is 275 MPa (40,000 psi), and the modulus of elasticity is 115 GPa (16.7 x 10^6 psi). What is the maximum load that may be applied to a specimen with a cross-sectional area of 325 mm^2 (0.5 in.^2) without plastic deformation?", "answer": "the maximum load that may be applied without plastic deformation is 89,375 n (20,000 lb_f).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（应力=载荷/面积）来求解最大载荷，答案也是具体的数值计算结果。 | 知识层次: 题目主要考查基本公式的应用和简单计算，即利用应力公式（应力=力/面积）来计算最大载荷，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（应力=力/面积）进行计算，无需组合多个公式或进行复杂的概念分析。解题步骤简单，只需将给定的应力值和面积代入公式即可得出最大载荷。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "89,375 N (20,000 lb_f)", "choice_question": "For a bronze alloy, the stress at which plastic deformation begins is 275 MPa (40,000 psi), and the modulus of elasticity is 115 GPa (16.7 x 10^6 psi). What is the maximum load that may be applied to a specimen with a cross-sectional area of 325 mm^2 (0.5 in.^2) without plastic deformation?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "89,375 N (20,000 lb_f)", "B": "37,375 N (8,400 lb_f) - calculated using elastic modulus instead of yield stress", "C": "115,000 N (25,850 lb_f) - using the modulus value directly as stress", "D": "143,750 N (32,300 lb_f) - incorrectly doubling the yield stress for safety factor" }, "correct_answer": "A", "explanation": "The correct answer is calculated by multiplying the yield stress (275 MPa) by the cross-sectional area (325 mm²). Option B exploits confusion between elastic modulus and yield stress. Option C traps those who mistake modulus value for allowable stress. Option D introduces an incorrect safety factor application, a common engineering intuition trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 71, "question": "What are the characteristics of non-stoichiometric compounds?", "answer": "Characteristics of non-stoichiometric compounds: The formation and defect concentration of non-stoichiometric compounds are related to the nature and pressure of the atmosphere; they can be regarded as solid solutions of higher-valent and lower-valent compounds; the defect concentration is related to temperature, which can be seen from the equilibrium constant; non-stoichiometric compounds are all semiconductors.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释非化学计量化合物的特征，答案提供了详细的文字解释和论述，符合简答题的特点。 | 知识层次: 题目要求解释非化学计量化合物的特性，涉及多个相关概念（如缺陷浓度、温度影响、半导体性质等）的综合分析，需要理解并关联这些概念，而不仅仅是记忆基础定义。虽然不涉及复杂计算，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题型中，该题目属于较高难度。正确选项涵盖了非化学计量化合物的多个关键特征，包括与气氛性质和压力的关系、高低价态化合物的固溶体性质、缺陷浓度与温度的关系以及半导体特性。这些知识点需要考生不仅理解基本概念，还能进行多角度分析和概念关联。此外，题目要求考生能够综合这些信息并识别出正确选项，这在选择题型中属于较为复杂的综合分析任务。", "convertible": true, "correct_option": "The formation and defect concentration of non-stoichiometric compounds are related to the nature and pressure of the atmosphere; they can be regarded as solid solutions of higher-valent and lower-valent compounds; the defect concentration is related to temperature, which can be seen from the equilibrium constant; non-stoichiometric compounds are all semiconductors.", "choice_question": "Which of the following describes the characteristics of non-stoichiometric compounds?", "conversion_reason": "The answer is a standard description of the characteristics of non-stoichiometric compounds, which can be converted into a multiple-choice question format by presenting it as the correct option among several distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The formation and defect concentration of non-stoichiometric compounds are related to the nature and pressure of the atmosphere; they can be regarded as solid solutions of higher-valent and lower-valent compounds; the defect concentration is related to temperature, which can be seen from the equilibrium constant; non-stoichiometric compounds are all semiconductors.", "B": "Non-stoichiometric compounds have fixed composition ratios like stoichiometric compounds, but their properties vary due to point defects; their electrical conductivity is always higher than stoichiometric counterparts; defect formation is independent of temperature.", "C": "Non-stoichiometric compounds exhibit variable composition due to interstitial defects only; their defect concentration is solely determined by the cooling rate during synthesis; they are exclusively insulators regardless of defect type.", "D": "The deviation from stoichiometry in these compounds is always caused by Schottky defects; their defect concentration follows Arrhenius behavior but is unaffected by atmospheric conditions; they exhibit metallic conductivity when defects are present." }, "correct_answer": "A", "explanation": "Option A is correct as it comprehensively describes all key characteristics of non-stoichiometric compounds: atmospheric dependence, solid solution nature, temperature-dependent defect concentration through equilibrium constant, and semiconducting behavior. Option B uses cognitive bias by suggesting fixed composition (false) and temperature-independent defects (false). Option C employs professional intuition traps by limiting defects to only interstitial type (false) and claiming exclusive insulator behavior (false). Option D creates a multi-level verification trap by incorrectly specifying only Schottky defects (false) while mixing correct Arrhenius behavior with incorrect metallic conductivity claim (false).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 956, "question": "Briefly describe the solid-state phase transformation process of steel with a carbon content of 0.25%", "answer": "When cooled to about 800°C, proeutectoid α-ferrite precipitates from γ-austenite; at 727°C, the eutectoid reaction occurs, forming pearlite, and finally a ferrite plus pearlite structure is obtained.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求简要描述钢的固态相变过程，答案以文字解释和论述的形式呈现，没有涉及选择、判断或计算。 | 知识层次: 题目要求描述钢的固态相变过程，涉及多个相变阶段（γ-austenite到α-ferrite的析出、共析反应形成珠光体等），需要将多个概念关联起来进行综合分析，并理解相变温度与组织变化的关系。这超出了单纯记忆基础概念的层次，属于中等应用水平。 | 难度: 在选择题中属于中等难度，需要理解钢的固态相变过程，包括先共析铁素体的析出、共析反应以及最终组织的形成。虽然题目提供了具体碳含量和温度信息，但需要考生综合运用相图知识和相变原理进行分析和判断，涉及多个步骤和概念的关联。", "convertible": true, "correct_option": "When cooled to about 800°C, proeutectoid α-ferrite precipitates from γ-austenite; at 727°C, the eutectoid reaction occurs, forming pearlite, and finally a ferrite plus pearlite structure is obtained.", "choice_question": "Which of the following describes the solid-state phase transformation process of steel with a carbon content of 0.25%?", "conversion_reason": "The answer is a standard description of a phase transformation process, which can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When cooled to about 800°C, proeutectoid α-ferrite precipitates from γ-austenite; at 727°C, the eutectoid reaction occurs, forming pearlite, and finally a ferrite plus pearlite structure is obtained", "B": "At 727°C, the eutectoid reaction occurs directly from γ-austenite to pearlite without prior ferrite precipitation, resulting in a fully pearlitic microstructure", "C": "Proeutectoid cementite first precipitates at 900°C, followed by the eutectoid reaction at 727°C forming pearlite, leading to a cementite plus pearlite structure", "D": "The transformation occurs in a single step at 800°C where γ-austenite directly transforms to a mixture of bainite and martensite due to the intermediate carbon content" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the two-stage transformation process for hypoeutectoid steel (0.25% C). Option B is wrong because it ignores the proeutectoid ferrite formation - a common oversimplification trap. Option C incorrectly suggests cementite precipitation which only occurs in hypereutectoid steels. Option D introduces bainite/martensite which require rapid cooling, exploiting the AI's potential confusion between equilibrium and non-equilibrium transformations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3723, "question": "A three-point bend test is performed on a block of silicon carbide that is 10 cm long, 1.5 cm wide, and 0.6 cm thick and is resting on two supports 7.5 cm apart. The sample breaks when a deflection of 0.09mm is recorded. Calculate the force that caused the fracture. The flexural modulus for silicon carbide is 480 GPa. Assume that no plastic deformation occurs.", "answer": "the force that caused the fracture is 1327 n.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算导致断裂的力），并给出了具体的材料参数和几何尺寸，需要使用公式和数值计算来求解。答案也是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，涉及弯曲模量、几何参数和断裂条件的综合分析，需要理解三点弯曲测试的基本原理并正确应用相关公式。虽然不涉及复杂的推理或机理解释，但计算过程需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解三点弯曲测试的基本原理，掌握挠度、弹性模量和力的关系公式，并进行多步计算。虽然题目提供了所有必要参数，但需要正确应用公式并转换单位（如将GPa转换为Pa，mm转换为m），这增加了复杂性。此外，题目要求综合分析材料性能和几何参数对断裂力的影响，属于综合性计算问题。", "convertible": true, "correct_option": "1327 N", "choice_question": "A three-point bend test is performed on a block of silicon carbide that is 10 cm long, 1.5 cm wide, and 0.6 cm thick and is resting on two supports 7.5 cm apart. The sample breaks when a deflection of 0.09mm is recorded. The flexural modulus for silicon carbide is 480 GPa. Assuming no plastic deformation occurs, what is the force that caused the fracture?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1327 N", "B": "2654 N", "C": "663.5 N", "D": "3981 N" }, "correct_answer": "A", "explanation": "正确答案A是通过三点弯曲公式F=(4Ebh³δ)/L³计算得出，其中E=480GPa, b=1.5cm, h=0.6cm, δ=0.09mm, L=7.5cm。干扰项B是忘记将厚度h进行立方运算的结果，利用了常见的计算错误认知偏差。干扰项C是错误地将支撑间距L进行平方而非立方运算的结果，利用了公式记忆混淆。干扰项D是同时错误地将厚度和支撑间距都进行平方运算的结果，设置了多层次验证陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3373, "question": "What is the reason why alloying elements improve the tempering stability of steel?", "answer": "Non-carbide forming elements have the effect of delaying the decomposition of martensite. This is because they can dissolve into ε-carbide and stabilize it, slowing down the aggregation rate of carbides. Compared to carbon steel, the final decomposition temperature of martensite may be delayed to 350-500℃, which is 100-150℃ higher than that of carbon steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释合金元素提高钢的回火稳定性的原因，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释合金元素提高钢的回火稳定性的机理，涉及非碳化物形成元素对马氏体分解的延迟作用、ε-碳化物的稳定化以及碳化物聚集速率的减缓等复杂过程。这需要综合运用材料科学中的相变理论、合金化原理和热力学知识，进行深入的推理分析和机理解释。 | 难度: 在选择题中属于最高难度等级，题目要求考生深入理解合金元素对钢回火稳定性的影响机理，包括非碳化物形成元素如何延迟马氏体分解、稳定ε碳化物以及减缓碳化物聚集速率等复杂现象。需要综合运用材料科学知识进行推理分析，并解释背后的物理冶金原理，这远超出简单记忆或基础理解的范畴。", "convertible": true, "correct_option": "Non-carbide forming elements have the effect of delaying the decomposition of martensite. This is because they can dissolve into ε-carbide and stabilize it, slowing down the aggregation rate of carbides. Compared to carbon steel, the final decomposition temperature of martensite may be delayed to 350-500℃, which is 100-150℃ higher than that of carbon steel.", "choice_question": "Which of the following best explains why alloying elements improve the tempering stability of steel?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Alloying elements increase the activation energy required for carbide precipitation by altering the interfacial energy between matrix and precipitates", "B": "Alloying elements reduce the diffusion coefficient of carbon by increasing lattice distortion energy", "C": "Non-carbide forming elements delay martensite decomposition by stabilizing ε-carbide through solid solution effects", "D": "Strong carbide formers preferentially bind carbon atoms, reducing their mobility during tempering" }, "correct_answer": "C", "explanation": "Correct answer C describes the actual mechanism where non-carbide forming elements dissolve into and stabilize ε-carbide, delaying martensite decomposition. Option A uses a plausible-sounding but incorrect interfacial energy argument. Option B mixes correct concepts (lattice distortion) with wrong application (carbon diffusion). Option D describes a real phenomenon but for strong carbide formers, which is not the primary mechanism for tempering stability improvement.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2237, "question": "Determine whether the following statement is correct. (13) Recrystallization is a nucleation-growth process, so it is also a phase transformation process.", "answer": "Incorrect. Although recrystallization is a nucleation-growth process, the crystal lattice type does not change, so it is not a phase transformation process.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断陈述的正确性，答案明确指出了陈述的错误并解释了原因，符合判断题的特征。 | 知识层次: 题目考查对再结晶过程和相变过程这两个基础概念的理解和区分，属于基础概念的记忆和辨析范畴 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆（再结晶和相变），但需要考生理解两个关键概念之间的关系（再结晶是形核-生长过程但不改变晶格类型）。这超出了简单的定义记忆（等级1），但尚未达到需要分析复杂概念陈述的程度（等级3）。考生需要正确区分形核-生长过程和相变过程的本质区别，这属于概念理解层面的对错判断。", "convertible": true, "correct_option": "Incorrect. Although recrystallization is a nucleation-growth process, the crystal lattice type does not change, so it is not a phase transformation process.", "choice_question": "Determine whether the following statement is correct. (13) Recrystallization is a nucleation-growth process, so it is also a phase transformation process.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature due to their ionic/covalent bonding nature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature due to their bonding nature, some transformation-toughened ceramics like partially stabilized zirconia can exhibit significant plastic deformation through stress-induced phase transformation mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4550, "question": "What is the magnitude of the voltage generated in the Zn/Zn2+ concentration cell with Zn2+ concentrations of 1.0 M and 10^-2 M?", "answer": "The magnitude of the voltage is 0.0592 v.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算Zn/Zn2+浓度电池的电压大小，需要使用能斯特方程等公式进行数值计算，答案是一个具体的数值结果（0.0592 v），符合计算题的特征。 | 知识层次: 题目考查的是浓度电池电压的计算，需要应用能斯特方程进行简单的数值计算，属于基本公式的直接应用，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目仅要求应用Nernst方程的基本形式来计算浓度电池的电压，且给定的浓度差异直接可代入公式得出结果，无需复杂的推导或多步骤计算。", "convertible": true, "correct_option": "0.0592 v", "choice_question": "What is the magnitude of the voltage generated in the Zn/Zn2+ concentration cell with Zn2+ concentrations of 1.0 M and 10^-2 M?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0592 V", "B": "0.0296 V", "C": "0.1184 V", "D": "0.0888 V" }, "correct_answer": "A", "explanation": "The correct answer is A (0.0592 V) calculated using the Nernst equation for a concentration cell: E = (0.0592/n)log(Q), where n=2 for Zn2+ and Q=100. Option B (0.0296 V) is a common error from forgetting to divide by n=2. Option C (0.1184 V) doubles the correct value, exploiting AI's tendency to overcompensate. Option D (0.0888 V) is a random plausible value that might catch AI's pattern-matching errors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2091, "question": "How to obtain the mass and Cu content of solid α3 by heating solid α2 to melting and slowly cooling it to 920°C, then pouring off the liquid?", "answer": "Reheat α2 to melting, slowly cool to 920°C, pour off the liquid, leaving only α3, with a mass of 260g and w_Cu≈0.02.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字描述步骤和结果来解答，答案提供了具体的操作步骤和最终结果，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目涉及多步操作（加热、冷却、倒出液体）和综合分析（确定固体α3的质量和铜含量），需要理解相变过程和成分变化，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解相图概念、掌握多步计算过程，并能将加热冷却操作与物质组成变化关联起来。题目要求考生综合运用相变知识和成分计算能力，但选项已提供关键数值，降低了纯计算难度。", "convertible": true, "correct_option": "Reheat α2 to melting, slowly cool to 920°C, pour off the liquid, leaving only α3, with a mass of 260g and w_Cu≈0.02.", "choice_question": "How can you obtain the mass and Cu content of solid α3 by heating solid α2 to melting and slowly cooling it to 920°C, then pouring off the liquid?", "conversion_reason": "The answer is a specific procedure with clear steps and numerical values, making it suitable for conversion into a multiple-choice question where the correct option is the exact procedure described.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Reheat α2 to melting, slowly cool to 920°C, pour off the liquid, leaving only α3, with a mass of 260g and w_Cu≈0.02", "B": "Reheat α2 to melting, rapidly quench to 920°C, pour off the liquid, leaving α3 with a mass of 260g and w_Cu≈0.15", "C": "Reheat α2 to melting, slowly cool to 920°C, pour off the liquid, leaving α3 with a mass of 300g and w_Cu≈0.02", "D": "Reheat α2 to melting, slowly cool to 920°C, retain both phases, giving α3 with a mass of 260g and w_Cu≈0.02" }, "correct_answer": "A", "explanation": "The correct answer requires understanding that slow cooling allows phase separation and pouring off the liquid leaves only α3. Option B incorrectly suggests rapid quenching would give the same result. Option C overestimates the mass due to incomplete phase separation. Option D is wrong because retaining both phases contradicts the pouring step. The cooling rate and phase separation are key factors AI models might misjudge.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1445, "question": "There are five possible types of cementite in iron-carbon alloys, listed in order of formation temperature from high to low: (22) cementite, (23) cementite, (24) cementite, (25) cementite, and (26) cementite.", "answer": "(22) primary; (23) eutectic; (24) secondary; (25) eutectoid; (26) tertiary;", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写特定术语（五种渗碳体类型），答案以文字形式给出，属于需要补充完整信息的简答题类型。 | 知识层次: 题目考查对铁碳合金中不同类型渗碳体的分类和形成温度顺序的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个类型的cementite，但主要是要求考生记忆并正确排序不同cementite的形成温度顺序。这需要考生掌握基础概念和分类，但不需要进行复杂的分析或推理。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "primary; eutectic; secondary; eutectoid; tertiary", "choice_question": "In iron-carbon alloys, the five possible types of cementite, listed in order of formation temperature from high to low, are:", "conversion_reason": "The answer is a standard sequence of terms, which can be presented as a multiple-choice question where the correct sequence is one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "primary; eutectic; secondary; eutectoid; tertiary", "B": "eutectic; primary; secondary; eutectoid; tertiary", "C": "primary; secondary; eutectic; eutectoid; tertiary", "D": "eutectic; primary; eutectoid; secondary; tertiary" }, "correct_answer": "A", "explanation": "The correct order is based on the decreasing temperature of formation in the iron-carbon phase diagram. Primary cementite forms directly from the liquid at the highest temperature, followed by eutectic during the eutectic reaction, then secondary from austenite, eutectoid during pearlite formation, and finally tertiary from ferrite. Option B swaps primary and eutectic, a common mistake when confusing primary solidification with eutectic reaction. Option C incorrectly places secondary before eutectic, exploiting confusion between precipitation sequences. Option D introduces multiple swaps, particularly dangerous as it places eutectoid before secondary, a subtle but critical error in understanding phase transformation hierarchies.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4383, "question": "List the four classifications of steels.", "answer": "Low Carbon Steels, Medium Carbon Steels, High Carbon Steels, High Alloy Steels (Stainless and Tool)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列出钢材的四种分类，需要文字回答而非选择或判断 | 知识层次: 题目考查对钢材分类的基本概念记忆，属于基础概念记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆和识别钢材的四种基本分类，属于基础概念记忆层次。题目仅涉及简单的分类列举，无需解释或比较分析，解题步骤简单直接，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "Low Carbon Steels, Medium Carbon Steels, High Carbon Steels, High Alloy Steels (Stainless and Tool)", "choice_question": "Which of the following lists the four classifications of steels?", "conversion_reason": "The answer is a standard list of terms, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Low Carbon Steels, Medium Carbon Steels, High Carbon Steels, High Alloy Steels", "B": "Ferritic, Austenitic, Martensitic, Duplex", "C": "Plain Carbon Steels, Low Alloy Steels, Tool Steels, Stainless Steels", "D": "Hypoeutectoid, Eutectoid, Hypereutectoid, Ledeburitic" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately represents the four fundamental classifications based on carbon content and alloying elements. Option B is a trap for AI models as it lists microstructural classifications of stainless steels, not general steel categories. Option C exploits the common confusion between functional classifications (like tool steels) and fundamental compositional classifications. Option D targets advanced AI by presenting phase diagram terminology that applies to steel but isn't a classification system, leveraging the model's tendency to overcomplicate answers with technical terms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4555, "question": "Under what conditions is activation polarization rate controlling?", "answer": "Activation polarization is rate controlling when the reaction rate is low and/or the concentration of active species in the liquid solution is high.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释在什么条件下活化极化是速率控制步骤，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求理解活化极化控制速率的条件，涉及反应速率和活性物种浓度的综合分析，需要将多个概念关联起来进行解释，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及激活极化在特定条件下的控制作用，要求考生能够综合理解反应速率和活性物种浓度之间的关系，并进行概念关联。虽然不需要多步计算，但需要对电化学动力学有较好的掌握，属于中等应用层次的知识点。", "convertible": true, "correct_option": "Activation polarization is rate controlling when the reaction rate is low and/or the concentration of active species in the liquid solution is high.", "choice_question": "Under what conditions is activation polarization rate controlling?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When the reaction rate is low and/or the concentration of active species in the liquid solution is high", "B": "When the diffusion rate is significantly slower than the charge transfer rate", "C": "Under high temperature conditions where thermal activation dominates", "D": "When the electrolyte concentration is below 0.1M and the current density is high" }, "correct_answer": "A", "explanation": "The correct answer is A because activation polarization becomes rate-controlling precisely under conditions of low reaction rates (where the activation barrier is significant) and/or high concentrations of active species (where concentration polarization is minimized). Option B incorrectly describes concentration polarization conditions. Option C is a thermal activation trap that ignores the fundamental definition of activation polarization. Option D combines two unrelated conditions that actually favor concentration polarization, creating a complex verification trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2366, "question": "In the copolymer of PVC vinyl chloride $(C_{2}H_{3}C)$ and PVA vinyl alcohol $(C_{4}H_{5}C)_{2}$, the ratio of vinyl chloride to vinyl alcohol is 10:1. If the average molar mass of the copolymer molecular chain is $\\lvert5000\\rvert\\lvert\\bar{\\mathbf{g}}/17\\rvert\\lvert\\bar{\\mathbf{U}}\\rvert$, find its degree of polymerization (DP).", "answer": "First, calculate the molar mass of the repeating unit. In question 49, the molar masses of PVC and PVA were determined to be $\\bar{6}\\bar{2}.45\\bar{5}\\bar{5}^{\\prime}\\bar{1}710\\bar{1}$ and $86\\\\mathrm{g/mol}$, respectively. In this copolymer, the ratio of PVC to PVA is 10:1, so the molar mass of the repeating unit is $111$ $$\\\\begin{array}{l l}{{}}&{{M=\\\\displaystyle\\\\frac{10}{11}\\\\mathrm{PVC}\\\\mathrm{\\\\Ddot{H}^{\\\\sharp}J}\\\\frac{\\\\mathrm{s}\\\\mathrm{s}}{\\\\mathrm{1}}\\\\mathrm{s}^{\\\\prime}\\\\mathrm{H}\\\\overline{{{\\\\mathcal{T}}}}^{\\\\sharp}\\\\mathrm{IW}\\\\mathrm{E}\\\\mathrm{H}+\\\\displaystyle\\\\frac{1}{11}\\\\mathrm{PVA}\\\\mathrm{\\\\Ddot{H}^{\\\\sharp}}}}\\\\ {{}}&{{=\\\\displaystyle[\\\\frac{10}{11}\\\\mathrm{6}2.45+\\\\frac{1}{11}86]\\\\mathrm{g}/\\\\mathrm{mol}=\\\\mathrm{64.6}\\\\mathrm{g}/\\\\mathrm{mol}}}\\\\end{array}$$ The degree of polymerization (DP) of the copolymer is: DP = molar mass of the copolymer / molar mass of the repeating unit = 16000g/mol / 64.6g/mol = 248", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，包括计算摩尔质量和聚合度，最终得出一个具体的数值结果。答案中展示了详细的计算步骤和公式应用，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括计算重复单元的摩尔质量（涉及PVC和PVA的摩尔质量及其比例），然后计算聚合度（DP）。这需要理解共聚物的组成和聚合度的概念，并进行综合计算。虽然不涉及复杂的机理分析或创新设计，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及计算共聚物的平均摩尔质量和聚合度，需要掌握PVC和PVA的摩尔质量计算，以及根据比例计算重复单元的摩尔质量。解题步骤包括多个计算环节，但题目提供了部分中间结果，降低了部分计算难度。", "convertible": true, "correct_option": "248", "choice_question": "In the copolymer of PVC vinyl chloride $(C_{2}H_{3}C)$ and PVA vinyl alcohol $(C_{4}H_{5}C)_{2}$, the ratio of vinyl chloride to vinyl alcohol is 10:1. If the average molar mass of the copolymer molecular chain is $5000 \\bar{g}/mol$, find its degree of polymerization (DP).", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, making it suitable for conversion into a multiple-choice format. The correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "248", "B": "310", "C": "192", "D": "275" }, "correct_answer": "A", "explanation": "正确答案A(248)通过计算单体平均摩尔质量和总摩尔质量得出。干扰项B(310)利用直觉上可能忽略的共聚物比例计算错误；C(192)基于错误的单体分子量假设；D(275)则通过错误地简化计算过程产生。这些干扰项专门针对AI在材料科学计算中常见的单位混淆、比例误解和简化错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 669, "question": "How does allotropic transformation affect the diffusion coefficient?", "answer": "In metals with allotropic transformation, the diffusion coefficient changes significantly with the alteration of crystal structure, and the diffusion coefficient of solute atoms in BCC crystal structure is larger than that in FCC.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释同素异构转变如何影响扩散系数，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求解释同素异构转变对扩散系数的影响机制，涉及晶体结构变化与扩散行为的关联分析，需要综合运用材料科学中的相变理论和扩散理论进行机理层面的解释，属于需要推理分析和综合运用的复杂问题。 | 难度: 在选择题型内，该题目属于高难度等级。题目要求考生不仅理解同素异构转变的基本概念，还需要掌握其对扩散系数的具体影响机制。正确选项涉及BCC和FCC晶体结构中扩散系数的比较，这需要考生具备深入的材料科学知识，能够对不同晶体结构中的原子扩散行为进行机理层面的解释和综合分析。这种题目在选择题中属于需要复杂分析能力的类型，符合等级5\"复杂现象全面分析\"的标准。", "convertible": true, "correct_option": "In metals with allotropic transformation, the diffusion coefficient changes significantly with the alteration of crystal structure, and the diffusion coefficient of solute atoms in BCC crystal structure is larger than that in FCC.", "choice_question": "How does allotropic transformation affect the diffusion coefficient?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diffusion coefficient increases in BCC due to lower atomic packing density, but decreases in FCC due to higher activation energy for vacancy formation", "B": "Allotropic transformation has negligible effect on diffusion coefficient as it primarily depends on temperature", "C": "The diffusion coefficient follows the same trend as Young's modulus changes during phase transformation", "D": "Diffusion becomes anisotropic with the transformation, but the average coefficient remains unchanged" }, "correct_answer": "A", "explanation": "Correct answer A combines two key facts: 1) BCC's more open structure facilitates diffusion, and 2) FCC's tighter packing increases activation energy. Option B exploits temperature-dependence bias while ignoring structural effects. Option C creates false correlation with mechanical properties. Option D uses correct 'anisotropic' concept but wrongly applies it to average coefficient.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2813, "question": "The yield strength of Mg alloy is 180MPa, E is 45GPa, find the maximum load that will not cause plastic deformation of a 10mm×2mm Mg plate.", "answer": "F=σA=180×10^6×10×2×10^-6=3600(N)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算最大负载），并应用了公式（F=σA），答案是一个具体的数值结果（3600N），符合计算题的特征。 | 知识层次: 题目涉及基本的公式应用（F=σA）和简单计算，不需要多步推理或综合分析，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（F=σA）进行计算，无需理解多个概念或进行复杂分析。解题步骤简单，仅涉及基本单位换算和乘法运算，属于最基础的难度等级。", "convertible": true, "correct_option": "3600 N", "choice_question": "The yield strength of Mg alloy is 180 MPa, E is 45 GPa. What is the maximum load that will not cause plastic deformation of a 10 mm × 2 mm Mg plate?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format with the correct option being the calculated result.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3600 N", "B": "9000 N", "C": "1800 N", "D": "8100 N" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the yield strength (180 MPa) multiplied by the cross-sectional area (10 mm × 2 mm = 20 mm²), giving 3600 N. Option B is incorrect as it uses the elastic modulus (45 GPa) instead of yield strength, creating a cognitive bias trap. Option C is half the correct value, exploiting a common calculation error. Option D is derived by incorrectly using both yield strength and elastic modulus together, representing a multi-parameter verification trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3201, "question": "What are the characteristics of the intermediate crystal zone in the ingot structure?", "answer": "The intermediate zone consists of columnar crystals. Its formation is primarily due to the increase in mold wall temperature, where the growth rate of crystal nuclei exceeds the nucleation rate, and heat dissipation is more favorable in the direction perpendicular to the mold wall. In the fine crystal zone, preferentially oriented grains grow into columnar crystals.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释中间晶区的特征，答案提供了详细的文字描述和论述，符合简答题的特点。 | 知识层次: 题目要求解释中间晶区的特征及其形成原因，涉及晶体生长速率与形核速率的关系、热传导方向的影响以及晶粒择优取向等概念的综合分析，需要将多个知识点关联起来进行解释，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及中间晶区的特征、形成原因以及与细晶区的关系，要求考生能够综合运用晶体生长和热传导的知识。虽然不需要复杂的计算，但需要对多个概念进行关联分析，符合等级3的综合分析和说明要求。", "convertible": true, "correct_option": "The intermediate zone consists of columnar crystals. Its formation is primarily due to the increase in mold wall temperature, where the growth rate of crystal nuclei exceeds the nucleation rate, and heat dissipation is more favorable in the direction perpendicular to the mold wall. In the fine crystal zone, preferentially oriented grains grow into columnar crystals.", "choice_question": "Which of the following best describes the characteristics of the intermediate crystal zone in the ingot structure?", "conversion_reason": "The answer is a standard description of the characteristics of the intermediate crystal zone, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The intermediate zone consists of columnar crystals formed due to preferential growth perpendicular to the mold wall when nucleation rate is exceeded by growth rate", "B": "The intermediate zone contains equiaxed crystals resulting from uniform cooling conditions and homogeneous nucleation throughout the melt", "C": "The intermediate zone exhibits dendritic structures with secondary arms due to constitutional undercooling and solute redistribution", "D": "The intermediate zone shows amorphous characteristics caused by rapid quenching effects from the mold wall" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the columnar crystal formation in the intermediate zone due to thermal gradient effects. Option B incorrectly describes equiaxed crystals which are characteristic of the central zone. Option C describes dendritic growth which occurs in specific alloy systems but not the general intermediate zone. Option D is completely wrong as amorphous structures cannot form under normal ingot casting conditions. The high difficulty comes from requiring precise understanding of solidification zones and resisting the intuitive pull of dendritic growth descriptions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2077, "question": "In the Al-Mg alloy, $x_{\\\\mathrm{Mg}}=0.05$, calculate the mass fraction of Mg ($w_{\\\\mathrm{Mg}}$) in the alloy (given that the relative atomic mass of Mg is 24.31 and Al is 26.98).", "answer": "$w_{\\\\mathrm{Mg}}=0.0453$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算，应用给定的相对原子质量和摩尔分数来计算镁的质量分数，答案是一个具体的数值结果。 | 知识层次: 题目考查基本的质量分数计算，仅需套用简单公式（质量分数=组分质量/总质量），涉及单一概念的直接应用和基本数值计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（质量分数计算公式）进行简单计算，无需复杂的推理或多步骤操作。题目提供了所有必要的数据，且计算过程直接明了，属于最基础的难度等级。", "convertible": true, "correct_option": "0.0453", "choice_question": "In the Al-Mg alloy, $x_{\\mathrm{Mg}}=0.05$, what is the mass fraction of Mg ($w_{\\mathrm{Mg}}$) in the alloy (given that the relative atomic mass of Mg is 24.31 and Al is 26.98)?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0453", "B": "0.0500", "C": "0.0431", "D": "0.0472" }, "correct_answer": "A", "explanation": "The correct answer is A (0.0453) because the mass fraction calculation requires accounting for the different atomic masses of Al and Mg. Option B (0.0500) is a common mistake where one might assume the mole fraction equals the mass fraction. Option C (0.0431) is a miscalculation that might occur if the atomic mass of Al is incorrectly used for Mg. Option D (0.0472) is a plausible but incorrect result from rounding errors in intermediate steps.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4491, "question": "An alternating copolymer is known to have a number-average molecular weight of 250,000g / mol and a degree of polymerization of 3420 . If one of the repeat units is styrene, which of ethylene, propylene, tetrafluoroethylene, and vinyl chloride is the other repeat unit? ", "answer": "propylene", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从给定的选项（ethylene, propylene, tetrafluoroethylene, and vinyl chloride）中选择正确的另一个重复单元，符合选择题的特征。 | 知识层次: 题目需要计算分子量并分析共聚物的结构，涉及多步计算和概念关联。首先需要理解数均分子量和聚合度的关系，然后通过计算确定重复单元的分子量，最后根据选项中的单体分子量进行匹配。这需要中等程度的认知能力和综合分析。 | 难度: 在选择题型中，该题目属于较高难度，需要考生进行多步计算（如分子量计算、重复单元推断）、概念关联（如共聚物结构、单体分子量）以及综合分析（排除法判断正确单体）。虽然提供了正确选项，但解题过程涉及多个知识点的综合应用和较复杂的逻辑推理，超出了基础选择题的范畴。", "convertible": true, "correct_option": "propylene", "choice_question": "An alternating copolymer is known to have a number-average molecular weight of 250,000g / mol and a degree of polymerization of 3420 . If one of the repeat units is styrene, which of the following is the other repeat unit?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer among the given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ethylene", "B": "Propylene", "C": "Tetrafluoroethylene", "D": "Vinyl chloride" }, "correct_answer": "B", "explanation": "The correct answer is propylene because the number-average molecular weight divided by the degree of polymerization gives the average molecular weight of the repeat unit pair (styrene + comonomer). Styrene has a molecular weight of 104 g/mol, so the comonomer must be 250,000/3420 - 104 ≈ 69 g/mol, which matches propylene (42 g/mol) when accounting for the alternating copolymer structure. Ethylene is too light (28 g/mol), tetrafluoroethylene is too heavy (100 g/mol), and vinyl chloride is close but incorrect (62.5 g/mol). The interference options exploit common mistakes in molecular weight calculations and copolymer structure assumptions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 756, "question": "Briefly describe the characteristics of grain growth", "answer": "Characteristics of grain growth: Grain growth is a process during heat treatment of a strain-free material where the average grain size continuously increases without altering its distribution. Within the bulk, grain sizes grow uniformly; during grain growth, pores remain at grain boundaries or their junctions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述晶粒生长的特征，答案以文字解释和论述的形式呈现，符合简答题的特点 | 知识层次: 题目考查对晶粒生长特性的基本概念记忆和理解，不涉及复杂分析或综合应用 | 难度: 在选择题型中，该题目要求考生理解和描述晶粒生长的基本特征，涉及对定义和基本原理的记忆与解释。虽然需要一定的概念理解，但不需要复杂的分析或比较，属于中等偏下的难度等级。", "convertible": true, "correct_option": "Grain growth is a process during heat treatment of a strain-free material where the average grain size continuously increases without altering its distribution. Within the bulk, grain sizes grow uniformly; during grain growth, pores remain at grain boundaries or their junctions.", "choice_question": "Which of the following best describes the characteristics of grain growth?", "conversion_reason": "The answer is a standard description of grain growth characteristics, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain growth is a process during heat treatment of a strain-free material where the average grain size continuously increases without altering its distribution. Within the bulk, grain sizes grow uniformly; during grain growth, pores remain at grain boundaries or their junctions.", "B": "Grain growth occurs through the migration of dislocations, resulting in non-uniform grain size distribution and the elimination of all porosity within the material's microstructure.", "C": "Grain growth is primarily driven by surface energy reduction, leading to the spontaneous formation of new grain boundaries and a decrease in average grain size during prolonged annealing.", "D": "During grain growth, smaller grains dissolve completely while larger grains maintain their original size, creating a bimodal grain size distribution with distinct small and large grain populations." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes grain growth as a uniform process in strain-free materials where the average grain size increases without changing the distribution pattern, with pores remaining at boundaries. Option B incorrectly associates grain growth with dislocation migration (characteristic of recovery/recrystallization) and complete pore elimination. Option C reverses the fundamental driving force (it's boundary energy reduction, not surface energy) and incorrectly states grain size decreases. Option D creates a false bimodal distribution scenario that contradicts the continuous nature of normal grain growth.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 771, "question": "As long as the temperature is above 0K, point defects always exist in crystals", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查晶体中点缺陷存在的基本原理，属于基础概念的记忆和理解 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆点缺陷在晶体中存在的条件即可作答，无需深入理解或分析。题目直接考察对\"温度高于0K时晶体中总是存在点缺陷\"这一基础概念的识记能力，属于最基础的难度等级。", "convertible": true, "correct_option": "√", "choice_question": "As long as the temperature is above 0K, point defects always exist in crystals", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In single-component systems, the equilibrium vacancy concentration is always proportional to exp(-Q_v/kT) where Q_v is the vacancy formation energy.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While this Arrhenius relationship generally holds for dilute solutions, it may not apply at very high vacancy concentrations where defect interactions become significant, or in systems with significant anharmonic effects. The 'always' makes this statement false as there are exceptions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3903, "question": "Which of the following microstructures is expected to be most similar to a single crystal in terms of structure and properties? Assume all of the options offer the same volumes and only consider grain boundaries as a crystalline defect for this question. (a) Textured polycrystal with about 10,000 grains (b) Random polycrystal with about 1,000,000 grains (c) Random polycrystal with about 1,000,000,000 grains (d) Amorphous", "answer": "(a) Textured polycrystal with about 10,000 grains", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从多个选项中选择最接近单晶结构和性能的微观结构，答案是从给定的选项中选择一个正确答案。 | 知识层次: 题目需要理解单晶和多晶的结构差异，并分析晶粒数量和取向对性能的影响。虽然涉及基础概念，但需要综合分析不同选项的微观结构特征，才能得出最接近单晶的选项。 | 难度: 在选择题中属于较高难度，需要综合理解晶体结构、晶界影响以及织构效应等多个概念。题目要求比较不同微观结构对单晶相似性的影响，涉及多步分析过程：首先需要排除非晶选项（d），然后比较随机多晶与织构多晶的晶界密度差异（b/c vs a），最后评估织构效应对性能的影响。这种综合分析过程超出了简单概念识别的范畴，属于复杂分析判断的题型要求。", "convertible": true, "correct_option": "(a) Textured polycrystal with about 10,000 grains", "choice_question": "Which of the following microstructures is expected to be most similar to a single crystal in terms of structure and properties? Assume all of the options offer the same volumes and only consider grain boundaries as a crystalline defect for this question.", "conversion_reason": "The original question is already in a multiple-choice format, which can be directly used as a single-choice question without modification. The correct option is clearly provided.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Highly textured polycrystal with 100 grains and 95% preferred orientation", "B": "Random polycrystal with 10 grains and no texture", "C": "Single crystal with 0.1% point defects concentration", "D": "Amorphous material annealed near glass transition temperature" }, "correct_answer": "A", "explanation": "The textured polycrystal (A) mimics single crystal behavior due to strong preferred orientation, despite having grain boundaries. Option B's random orientation destroys single-crystal-like properties. Option C is a distractor - while single crystals are ideal, the point defects create property deviations. Option D exploits the misconception that amorphous materials can approach crystalline order through annealing.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 440, "question": "In a ternary phase diagram, the degree of freedom at the eutectic temperature point is 0. At this time, it is a three-phase equilibrium.", "answer": "(×)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（三元相图中共晶温度点的自由度为0，此时为三相平衡），并要求判断其正误（答案给出×表示错误），这符合判断题的特征。 | 知识层次: 题目考查对三元相图中自由度概念和三相平衡条件的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念正误判断题，仅需记忆三元相图中共晶温度点的自由度概念即可作答。在选择题型中属于最简单的难度等级，不需要复杂的理解或分析过程。", "convertible": true, "correct_option": "(×)", "choice_question": "In a ternary phase diagram, the degree of freedom at the eutectic temperature point is 0. At this time, it is a three-phase equilibrium.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In a ternary phase diagram, the degree of freedom at the eutectic temperature point is 0. At this time, it is a three-phase equilibrium.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "In a ternary system, the Gibbs phase rule (F = C - P + 2) gives F = 3 - 3 + 2 = 2 degrees of freedom at the eutectic point. However, when temperature is fixed (at eutectic temperature), F becomes 1, not 0. The statement incorrectly applies binary system logic to a ternary system. This is a common misconception when transitioning from binary to ternary phase diagrams.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3196, "question": "Analyze the basic conditions for the formation of single crystals.", "answer": "The basic condition for forming a single crystal is to ensure that only one nucleus is produced (or only one nucleus can grow) when the liquid metal crystallizes, and it grows into a single crystal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求分析单晶形成的基本条件，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查单晶形成的基本条件，属于对基本原理的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并描述单晶形成的基本条件，而不仅仅是简单的定义记忆。正确选项要求考生能够解释为什么需要确保只有一个核生成或生长，这比单纯记忆定义需要更深一层的理解。因此，该题目在选择题型中属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "The basic condition for forming a single crystal is to ensure that only one nucleus is produced (or only one nucleus can grow) when the liquid metal crystallizes, and it grows into a single crystal.", "choice_question": "Which of the following describes the basic condition for the formation of single crystals?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Maintaining a precisely controlled cooling rate just below the melting point to suppress heterogeneous nucleation", "B": "Ensuring the melt has extremely high purity (>99.9999%) to eliminate all potential nucleation sites", "C": "Applying a strong directional temperature gradient to allow only one nucleus to dominate growth", "D": "Using a seed crystal and carefully controlling solidification parameters to prevent new nucleation" }, "correct_answer": "C", "explanation": "The correct answer is C because the fundamental condition is allowing only one nucleus to grow, which is best achieved through directional solidification. Option A is a common misconception - while controlled cooling is important, it alone cannot guarantee single crystal formation. Option B exploits purity obsession but even ultra-pure melts will have homogeneous nucleation. Option D describes a common industrial method but doesn't address the fundamental condition (multiple nuclei could still form adjacent to the seed).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2108, "question": "Point out the incorrect concept and correct it: In solid solution grains, dendritic segregation exists, the composition of the main axis differs from that of the interdendritic regions, so the entire grain is not a single phase.", "answer": "Therefore, the entire grain is a single phase.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求指出错误概念并纠正，类似于判断陈述的对错并给出正确陈述。答案形式是直接给出正确陈述，符合判断题的特征。 | 知识层次: 题目考查对固溶体晶粒中枝晶偏析和单相概念的基本理解，属于基础概念的记忆和判断。 | 难度: 该题目属于基础概念正误判断，仅需识别并纠正一个明确的错误概念（\"整个晶粒不是单相\"），正确选项直接给出了标准定义（\"整个晶粒是单相\"）。题目不涉及概念关系的分析或复杂推理，完全依赖对\"固溶体晶粒\"和\"枝晶偏析\"这两个基础定义的记忆性判断，符合等级1对知识点掌握深度和解题步骤简单性的要求。", "convertible": true, "correct_option": "Therefore, the entire grain is a single phase.", "choice_question": "Point out the incorrect concept and correct it: In solid solution grains, dendritic segregation exists, the composition of the main axis differs from that of the interdendritic regions, so the entire grain is not a single phase.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all metallic solid solutions, dendritic segregation always leads to the formation of multiple distinct phases within a single grain.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While dendritic segregation causes compositional variations within a grain, the grain remains a single phase as long as the crystal structure is uniform. The statement is incorrect because it uses absolute terms ('all', 'always') and misrepresents the phase rule. Compositional variation alone does not define separate phases - identical crystal structure is the key criterion for single-phase designation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 702, "question": "Network former", "answer": "A substance with single bond energy $\\geq335\\mathrm{kJ/mol}$ that can form glass alone.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Network former\"进行定义和解释，答案提供了详细的文字描述，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对\"Network former\"这一基本概念的定义和特性的记忆，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察对\"Network former\"基础定义的记忆，即能够单独形成玻璃且单键能量≥335kJ/mol的物质。题目不涉及概念解释或复杂体系分析，属于最基础的定义简答类型，符合等级1标准。", "convertible": true, "correct_option": "A substance with single bond energy $\\geq335\\mathrm{kJ/mol}$ that can form glass alone.", "choice_question": "Which of the following best defines a Network former?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A substance with single bond energy ≥335kJ/mol that can form glass alone", "B": "Any oxide compound capable of forming a continuous 3D network in molten state", "C": "A material with coordination number ≥4 that lowers glass transition temperature", "D": "An additive that modifies network connectivity without forming covalent bonds" }, "correct_answer": "A", "explanation": "The correct answer is A because it precisely defines a network former with the critical single bond energy threshold and independent glass-forming ability. Option B is a cognitive bias trap - while many network formers are oxides, the definition is not limited to oxides. Option C exploits professional intuition by mixing correct coordination number with incorrect Tg effect. Option D describes a network modifier, creating a common classification confusion trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2289, "question": "A contact device is made of silver-tungsten composite material. Its production process involves first creating a porous tungsten powder metallurgy blank, then infiltrating pure silver into the pores. Before silver infiltration, the density of the tungsten compact is 14.5 g/cm³. Calculate the volume fraction of the pores. The density of pure tungsten is known to be 19.3 g/cm³. Assume the tungsten blank is very thin and all pores are open.", "answer": "The pore density ρ_pore is obviously zero. Therefore, φ_pore = 1 - φ_tungsten = 1 - (ρc / ρ_tungsten) = 1 - (14.5 / 19.3) = 0.25", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解孔隙的体积分数，答案给出了具体的计算过程和数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过已知的钨块密度和纯钨密度来计算孔隙的体积分数。虽然需要理解孔隙和材料密度的关系，但计算过程直接且步骤单一，属于简单应用层次。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。解题仅需应用一个基本公式（体积分数计算公式），且计算步骤简单直接（只需代入已知数值进行除法运算）。题目中所有必要参数均已明确给出，无需进行任何概念转换或额外推导，完全符合等级1\"单一公式直接计算\"的特征。", "convertible": true, "correct_option": "0.25", "choice_question": "A contact device is made of silver-tungsten composite material. Its production process involves first creating a porous tungsten powder metallurgy blank, then infiltrating pure silver into the pores. Before silver infiltration, the density of the tungsten compact is 14.5 g/cm³. Calculate the volume fraction of the pores. The density of pure tungsten is known to be 19.3 g/cm³. Assume the tungsten blank is very thin and all pores are open.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.25", "B": "0.19", "C": "0.31", "D": "0.42" }, "correct_answer": "A", "explanation": "The correct answer is A (0.25) because the volume fraction of pores is calculated by (1 - (density of compact/density of pure tungsten)) = 1 - (14.5/19.3) = 0.25. Option B (0.19) is a common error from incorrectly using the density difference directly. Option C (0.31) results from confusing the calculation with relative density. Option D (0.42) is a trap for those who mistakenly consider silver's density in the pre-infiltration state.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4554, "question": "Cite the major differences between activation and concentration polarizations.", "answer": "Activation polarization is the condition wherein a reaction rate is controlled by one step in a series of steps that takes place at the slowest rate. For corrosion, activation polarization is possible for both oxidation and reduction reactions. Concentration polarization occurs when a reaction rate is limited by diffusion in a solution. For corrosion, concentration polarization is possible only for reduction reactions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述激活极化和浓度极化的主要区别，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对激活极化和浓度极化这两个基本概念的定义和区别的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生能够解释和描述两个相关但不同的概念（激活极化和浓度极化），并指出它们在腐蚀反应中的具体应用差异。虽然涉及多个概念，但题目提供了明确的定义和区分点，不需要进行复杂的推导或综合分析，属于概念解释和描述层次的难度。", "convertible": true, "correct_option": "Activation polarization is the condition wherein a reaction rate is controlled by one step in a series of steps that takes place at the slowest rate. For corrosion, activation polarization is possible for both oxidation and reduction reactions. Concentration polarization occurs when a reaction rate is limited by diffusion in a solution. For corrosion, concentration polarization is possible only for reduction reactions.", "choice_question": "Which of the following correctly describes the major differences between activation and concentration polarizations?", "conversion_reason": "The answer is a standard explanation of the differences between activation and concentration polarizations, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Activation polarization is rate-limited by the slowest electrochemical step, while concentration polarization is limited by mass transport of reactants to the electrode surface", "B": "Both types of polarization occur simultaneously in all corrosion reactions, with activation controlling oxidation and concentration controlling reduction", "C": "Activation polarization dominates in high-concentration electrolytes, while concentration polarization prevails in dilute solutions regardless of reaction type", "D": "The key difference lies in their temperature dependence - activation polarization decreases with temperature while concentration polarization increases" }, "correct_answer": "A", "explanation": "Correct answer A precisely distinguishes the fundamental mechanisms: activation relates to reaction kinetics while concentration concerns mass transport. Option B incorrectly generalizes that both always occur together with specific reaction assignments. Option C reverses the actual concentration dependence and oversimplifies the solution effects. Option D creates a false dichotomy about temperature effects, when in reality both polarizations generally decrease with increasing temperature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2357, "question": "Is the glass transition temperature of ordinary window glass above or below room temperature?", "answer": "The glass transition temperature of ordinary window glass should be above room temperature. If it were below room temperature, the glass would remain in a liquid state at room temperature, albeit with high viscosity and some fluidity, meaning the atoms would still be delocalized. Consequently, it could not maintain a fixed shape at room temperature.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断\"普通窗玻璃的玻璃化转变温度是否高于室温\"这一陈述的对错，答案给出了明确的判断和解释，符合判断题的特征。 | 知识层次: 题目考查对玻璃转变温度这一基本概念的记忆和理解，以及其在室温下的状态判断，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅要求判断普通窗玻璃的玻璃化转变温度是否高于室温，属于对基础概念的记忆性知识。正确选项直接给出了结论，不需要复杂的分析或推理过程，因此难度等级为1。", "convertible": true, "correct_option": "The glass transition temperature of ordinary window glass should be above room temperature. If it were below room temperature, the glass would remain in a liquid state at room temperature, albeit with high viscosity and some fluidity, meaning the atoms would still be delocalized. Consequently, it could not maintain a fixed shape at room temperature.", "choice_question": "Is the glass transition temperature of ordinary window glass above or below room temperature?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The glass transition temperature of all amorphous polymers is always below room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because the glass transition temperature (Tg) of amorphous polymers varies widely depending on their chemical structure. While some polymers like polyisoprene have Tg below room temperature, others like polystyrene have Tg well above room temperature. The use of 'always' makes this statement incorrect. A key misunderstanding would be assuming all amorphous materials behave similarly at room temperature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4389, "question": "Cite three characteristics of ferrous alloys that limit their utilization.", "answer": "Disadvantages of ferrous alloys are: (1) They are susceptible to corrosion. (2) They have a relatively high density. (3) They have relatively low electrical conductivities.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举铁基合金的三个限制其应用的特性，答案以文字解释和论述的形式给出，没有选项或计算要求。 | 知识层次: 题目考查对铁基合金基本特性的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目要求考生回忆并列举铁基合金的三个限制性特征，属于概念解释和描述层次。虽然需要记忆多个特点，但都属于基础概念记忆范畴，无需复杂分析或比较。", "convertible": true, "correct_option": "They are susceptible to corrosion.", "choice_question": "Which of the following is a characteristic of ferrous alloys that limits their utilization?", "conversion_reason": "The original question asks for three characteristics of ferrous alloys that limit their use. The answer provides specific disadvantages, which can be converted into a multiple-choice format by selecting one of the given disadvantages as the correct option. The question can be rephrased to fit a multiple-choice format by asking for one of the limiting characteristics.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Higher stacking fault energy compared to FCC metals", "B": "Negative temperature coefficient of resistivity", "C": "Lower dislocation mobility than ceramic materials", "D": "Anomalous Hall effect at room temperature" }, "correct_answer": "A", "explanation": "Correct answer is A because ferrous alloys (BCC structure) generally have higher stacking fault energy than FCC metals, which affects their deformation mechanisms. Option B exploits confusion with semiconductor behavior, Option C reverses the actual dislocation mobility relationship, and Option D introduces an unrelated quantum phenomenon to mislead.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4535, "question": "In an aligned and continuous glass fiber-reinforced nylon 6,6 composite, the fibers are to carry 94% of a load applied in the longitudinal direction. What will be the tensile strength of this composite? Assume that the matrix stress at fiber failure is 30 MPa (4350 psi).", "answer": "the tensile strength of this composite is 1354 mpa (196,400 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解复合材料的拉伸强度，答案是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，涉及纤维和基体的应力分配，需要应用复合材料力学中的基本公式，并进行综合分析。虽然计算过程不复杂，但需要理解复合材料中各相的作用和相互关系，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解复合材料力学的基本概念（如载荷分配、纤维和基体的应力关系），并进行多步计算（包括百分比转换和应力叠加）。虽然题目提供了部分参数，但仍需综合分析才能得出正确结论，属于综合性计算问题。", "convertible": true, "correct_option": "1354 MPa (196,400 psi)", "choice_question": "In an aligned and continuous glass fiber-reinforced nylon 6,6 composite, the fibers are to carry 94% of a load applied in the longitudinal direction. What will be the tensile strength of this composite? Assume that the matrix stress at fiber failure is 30 MPa (4350 psi).", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1354 MPa (196,400 psi)", "B": "1270 MPa (184,200 psi)", "C": "1420 MPa (206,000 psi)", "D": "1180 MPa (171,100 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A (1354 MPa) as it properly accounts for the 94% load carried by fibers and the matrix stress contribution. Option B underestimates by incorrectly assuming partial fiber-matrix debonding. Option C overestimates by neglecting matrix stress limitations. Option D results from erroneously using the matrix's yield strength instead of its stress at fiber failure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1666, "question": "Crystals can be classified into seven crystal systems based on the order and number of rotation axes and rotoinversion axes: cubic crystal system, trigonal crystal system, tetragonal crystal system, —(1), —(2)—, —(3), and _(4).", "answer": "(1) Hexagonal crystal system; (2) Orthorhombic crystal system; (3) Monoclinic crystal system; (4) Triclinic crystal system", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写缺失的晶体系统名称，答案需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目考查对晶体系统分类的基本概念记忆，只需回忆并填写七种晶体系统的名称，不涉及应用或分析。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目要求填写晶体系统的分类，只需要记忆七个晶体系统的名称即可完成。不需要进行概念解释或复杂的概念体系阐述，解题步骤简单，仅需回忆基础知识。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Hexagonal crystal system; Orthorhombic crystal system; Monoclinic crystal system; Triclinic crystal system", "choice_question": "Crystals can be classified into seven crystal systems based on the order and number of rotation axes and rotoinversion axes. Which of the following are the missing crystal systems?", "conversion_reason": "The answer is a standard list of terms, which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hexagonal crystal system", "B": "Trigonal crystal system", "C": "Tetragonal crystal system", "D": "Cubic crystal system" }, "correct_answer": "A", "explanation": "The correct answer is A because the hexagonal crystal system is one of the seven fundamental crystal systems. Options B, C, and D are already listed in the original question as given crystal systems, making them incorrect choices for the missing systems. This question exploits the cognitive bias of selecting familiar terms (like trigonal or cubic) even when they don't fit the context of identifying missing systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4131, "question": "A rod of some material 0.50{m} long elongates 0.40mm on heating from 50^{\\circ} C to 151^{\\circ} C. What is the value of the linear coefficient of thermal expansion for this material?\n(A) 5.30 × 10^{-6}\\left({ }^{\\circ} C\\right)^{-1}\n(B) 7.92 × 10^{-6}\\left({ }^{\\circ} C C\\right)^{-1}\n(C) 1.60 × 10^{-5}\\left({ }^{\\circ} C\\right)^{-1}\n(D) 1.24 × 10^{-6}\\left({ }^{\\circ} C_{-}^{1}\\right.", "answer": "the linear coefficient of thermal expansion for this material is 7.92 × 10^{-6} \\left(^{\\circ}c\\right)^{-1}, which is answer b.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的选项中选择正确的线性热膨胀系数值，并且提供了多个选项供选择 | 知识层次: 题目考查的是线性热膨胀系数的基本公式应用，只需要套用公式进行简单计算即可得出答案，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单难度。题目仅需要直接套用线性热膨胀系数的基本公式，并进行简单的数值计算。解题步骤不涉及公式变形或多步骤选择，仅需正确识别和应用公式即可得出答案。因此，在选择题型内属于等级2的简单公式选择和应用难度。", "convertible": true, "correct_option": "B", "choice_question": "A rod of some material 0.50{m} long elongates 0.40mm on heating from 50^{\\circ} C to 151^{\\circ} C. What is the value of the linear coefficient of thermal expansion for this material?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option provided.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.30 × 10^{-6} (°C)^{-1}", "B": "7.92 × 10^{-6} (°C)^{-1}", "C": "1.60 × 10^{-5} (°C)^{-1}", "D": "1.24 × 10^{-6} (°C)^{-1}" }, "correct_answer": "B", "explanation": "The linear coefficient of thermal expansion (α) is calculated using the formula: α = ΔL / (L₀ × ΔT), where ΔL is the change in length (0.40 mm = 0.0004 m), L₀ is the original length (0.50 m), and ΔT is the temperature change (151°C - 50°C = 101°C). Plugging in the values gives α = 0.0004 / (0.50 × 101) ≈ 7.92 × 10^{-6} (°C)^{-1}. Option A is a common miscalculation where the temperature change is incorrectly taken as 151°C instead of 101°C. Option C is a result of forgetting to convert mm to m. Option D is a typical error from misplacing the decimal point during calculation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1515, "question": "What is the common method to refine grains in casting process (the first method)", "answer": "Increase the cooling rate", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的工艺方法，需要简要的文字解释，而不是从选项中选择或判断对错 | 知识层次: 题目考查的是铸造过程中细化晶粒的基本方法，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需回忆铸造过程中细化晶粒的常见方法（增加冷却速率），无需复杂分析或比较多个概念。题目直接考察单一知识点的定义性内容，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "Increase the cooling rate", "choice_question": "What is the common method to refine grains in casting process (the first method)?", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by providing plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increase the cooling rate", "B": "Add grain refiners (e.g., TiB2)", "C": "Apply mechanical vibration during solidification", "D": "Use directional solidification" }, "correct_answer": "A", "explanation": "The correct answer is A because increasing cooling rate is the most fundamental and first method to refine grains by promoting more nucleation sites. Option B is a strong distractor as grain refiners are commonly used but represent a secondary method. Option C exploits the intuitive appeal of physical methods while being less fundamental. Option D is a reversal trap as directional solidification actually promotes columnar grain growth.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3296, "question": "Compare the diffusivity during bainitic transformation, pearlitic transformation, and martensitic transformation", "answer": "In pearlitic transformation, both iron and carbon atoms can diffuse; in bainitic transformation, carbon atoms diffuse while iron atoms do not; in martensitic transformation, neither iron nor carbon atoms diffuse.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对不同相变过程中的扩散性进行比较和解释，答案提供了详细的文字论述，符合简答题的特征。 | 知识层次: 题目要求比较三种不同相变过程中的扩散行为，涉及对扩散机制的理解和不同相变过程特点的综合分析。虽然不需要复杂的计算或推理，但需要对多个概念进行关联和比较，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它要求考生同时理解并比较三种不同的相变过程（珠光体转变、贝氏体转变和马氏体转变）中原子扩散行为的差异。这涉及到多个概念的关联和综合分析，需要考生不仅掌握每种相变的基本特征，还要能够区分铁原子和碳原子在不同条件下的扩散行为。这种多角度的分析论述在选择题型中属于较复杂的题目类型。", "convertible": true, "correct_option": "In pearlitic transformation, both iron and carbon atoms can diffuse; in bainitic transformation, carbon atoms diffuse while iron atoms do not; in martensitic transformation, neither iron nor carbon atoms diffuse.", "choice_question": "Which of the following correctly describes the diffusivity during bainitic transformation, pearlitic transformation, and martensitic transformation?", "conversion_reason": "The answer is a standard description that can be converted into a multiple-choice format by presenting it as one of several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In pearlitic transformation, both iron and carbon atoms can diffuse; in bainitic transformation, carbon atoms diffuse while iron atoms do not; in martensitic transformation, neither iron nor carbon atoms diffuse.", "B": "In pearlitic transformation, only carbon atoms diffuse; in bainitic transformation, both iron and carbon atoms diffuse; in martensitic transformation, neither iron nor carbon atoms diffuse.", "C": "In pearlitic transformation, both iron and carbon atoms can diffuse; in bainitic transformation, neither iron nor carbon atoms diffuse; in martensitic transformation, carbon atoms diffuse while iron atoms do not.", "D": "In all three transformations, carbon atoms can diffuse but iron atoms cannot diffuse." }, "correct_answer": "A", "explanation": "The correct answer is A because pearlitic transformation involves both iron and carbon diffusion, bainitic transformation involves only carbon diffusion, and martensitic transformation is diffusionless. Option B is incorrect because it reverses the diffusion behavior of bainite and pearlite. Option C is wrong as it incorrectly assigns diffusion to martensite and denies it for bainite. Option D is incorrect as it oversimplifies the diffusion behavior across all transformations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 615, "question": "What are the two basic phases that make up the room-temperature equilibrium microstructure of iron-carbon alloys?", "answer": "Cementite (Fe3C)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和论述铁碳合金在室温下的平衡微观结构的基本相，答案需要文字描述而非选择或判断 | 知识层次: 题目考查铁碳合金室温平衡显微组织的基本组成相，属于基础概念的记忆和理解范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别铁碳合金室温平衡显微组织的基本相之一——渗碳体（Fe3C）。这属于最基础的定义性知识，无需解释或分析，只需直接回忆即可作答。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Cementite (Fe3C)", "choice_question": "Which of the following is one of the two basic phases that make up the room-temperature equilibrium microstructure of iron-carbon alloys?", "conversion_reason": "The answer is a standard term (Cementite (Fe3C)), which can be used as a correct option in a multiple-choice question. The original question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cementite (Fe3C)", "B": "Martensite", "C": "Austenite", "D": "Pearlite" }, "correct_answer": "A", "explanation": "The correct answer is A because cementite (Fe3C) and ferrite are the two equilibrium phases at room temperature in iron-carbon alloys. Option B (Martensite) is a non-equilibrium phase formed by rapid quenching, exploiting the AI's potential confusion between equilibrium and non-equilibrium microstructures. Option C (Austenite) is a high-temperature phase, targeting the AI's possible failure to recognize temperature-dependent phase stability. Option D (Pearlite) is a lamellar microstructure (not a phase) composed of ferrite and cementite, designed to exploit the AI's potential confusion between phases and microstructural constituents.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4281, "question": "What is the difference between deformation by twinning and deformation by slip relative to mechanism?", "answer": "With slip deformation there is no crystallographic reorientation, whereas with twinning there is a reorientation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释两种变形机制的差异，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释变形机制中的孪生和滑移的区别，涉及晶体学重新取向的概念，需要对两种变形机制的深入理解和综合分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它要求考生不仅理解滑移和孪生两种变形机制的基本概念，还需要深入掌握它们在晶体学取向变化方面的差异。正确选项涉及机理层面的解释，需要考生具备综合分析和推理能力，能够区分两种变形机制的本质区别。这种题目在选择题中属于机理深度解释的层次，对知识掌握的要求较高。", "convertible": true, "correct_option": "With slip deformation there is no crystallographic reorientation, whereas with twinning there is a reorientation.", "choice_question": "What is the difference between deformation by twinning and deformation by slip relative to mechanism?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip occurs along specific crystallographic planes while twinning involves coordinated atomic movement", "B": "Twinning requires higher stress than slip due to simultaneous atomic movement", "C": "Slip preserves crystal orientation while twinning creates mirror-image lattice regions", "D": "Both mechanisms involve dislocation motion but twinning occurs at lower temperatures" }, "correct_answer": "C", "explanation": "Correct answer C precisely captures the key mechanistic difference: slip maintains original orientation through dislocation motion, while twinning creates reoriented mirror regions. Option A is partially correct but misses the orientation change aspect. Option B exploits the common misconception about stress requirements (twinning can occur at lower stresses in some materials). Option D combines two truths (dislocations and temperature effects) into a false conclusion about twinning mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4704, "question": "Suppose that CaO is added as an impurity to Li2O. If the Ca2+ substitutes for Li+, what kind of vacancies would you expect to form? How many of these vacancies are created for every Ca2+ added?", "answer": "For Ca2+ substituting for Li+ in Li2O, lithium vacancies would be created. For each Ca2+ substituting for Li+, one positive charge is added; in order to maintain charge neutrality, a single positive charge may be removed. Positive charges are eliminated by creating lithium vacancies, and for every Ca2+ ion added, a single lithium vacancy is formed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目需要解释Ca2+取代Li+时形成的空位类型及其数量，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要理解杂质掺杂对晶体缺陷的影响，并分析电荷平衡机制。虽然涉及基础概念，但需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要理解掺杂过程中的电荷平衡原理，并能将Ca2+替代Li+的电荷变化与空位形成机制关联起来。解题步骤涉及多步逻辑推理（电荷补偿计算、空位类型判断），且需要综合分析晶体缺陷与电荷守恒的相互作用。虽然题目提供了明确选项，但概念关联和计算复杂度明显高于基础选择题。", "convertible": true, "correct_option": "Lithium vacancies would be created, with one vacancy formed for every Ca2+ added.", "choice_question": "Suppose that CaO is added as an impurity to Li2O. If the Ca2+ substitutes for Li+, what kind of vacancies would you expect to form and how many vacancies are created for every Ca2+ added?", "conversion_reason": "The answer is a standard explanation involving specific terms (lithium vacancies) and a quantifiable relationship (one vacancy per Ca2+), making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Lithium vacancies, one per Ca2+", "B": "Oxygen vacancies, two per Ca2+", "C": "Lithium interstitials, one per Ca2+", "D": "Schottky defect pairs (Li+ and O2- vacancies), one pair per Ca2+" }, "correct_answer": "A", "explanation": "The correct answer is A because when Ca2+ (divalent) substitutes for Li+ (monovalent), charge compensation requires the creation of lithium vacancies to maintain electroneutrality, with one vacancy per Ca2+ added. Option B exploits the common misconception that oxygen vacancies would form to compensate for the higher cation charge. Option C reverses the defect type by suggesting interstitials instead of vacancies. Option D introduces a complex defect pair scenario that seems plausible for maintaining stoichiometry but is incorrect for this specific substitution case.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1833, "question": "Glass has the following general properties: (15)", "answer": "Continuous change in properties during transformation", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求描述玻璃的一般性质，需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查玻璃的一般性质，属于基础概念的记忆和理解，不需要复杂的分析或应用。 | 难度: 在选择题型中，此题仅考察对玻璃基本特性的记忆，属于最基础的定义性知识。题目直接给出正确选项\"Continuous change in properties during transformation\"，不需要任何概念解释或复杂分析，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Continuous change in properties during transformation", "choice_question": "Which of the following is a general property of glass?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Continuous change in properties during transformation", "B": "Sharp melting point at a defined temperature", "C": "Crystalline long-range order in atomic arrangement", "D": "Definite glass transition temperature for all compositions" }, "correct_answer": "A", "explanation": "The correct answer is A because glass exhibits a gradual transition in properties (viscosity, thermal expansion) during the glass transition range, which is a defining characteristic of amorphous materials. Option B exploits the common misconception that all materials have sharp melting points, while glass actually softens over a temperature range. Option C uses the intuitive but incorrect association with crystalline materials' ordered structure. Option D creates a trap by suggesting a universal Tg value, ignoring composition-dependent variation in glass transition behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1678, "question": "Analyze the crystal structures of CaO and MgO, and determine whether CaO-MgO meets the crystal structural conditions for forming a solid solution.", "answer": "Both CaO and MgO have FCC NaCl-type crystal structures, which meet the crystal structural conditions for forming a solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求分析CaO和MgO的晶体结构，并判断它们是否满足形成固溶体的晶体结构条件。答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求分析两种氧化物的晶体结构并判断它们是否满足形成固溶体的晶体结构条件，这涉及对晶体结构类型的理解和应用，以及综合分析能力。虽然知识点相对明确，但需要将多个概念关联起来进行判断，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求分析CaO和MgO的晶体结构，并判断它们是否满足形成固溶体的晶体结构条件。这需要掌握FCC NaCl型晶体结构的知识，并能将这一概念应用到具体材料中。虽然不需要进行复杂的计算，但需要对晶体结构有深入的理解，并能进行综合分析。因此，在选择题型中属于等级3的难度。", "convertible": true, "correct_option": "Both CaO and MgO have FCC NaCl-type crystal structures, which meet the crystal structural conditions for forming a solid solution.", "choice_question": "Analyze the crystal structures of CaO and MgO, and determine whether CaO-MgO meets the crystal structural conditions for forming a solid solution.", "conversion_reason": "The answer is a standard statement that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because both have FCC NaCl-type structures with similar lattice parameters (4.81Å for CaO vs 4.21Å for MgO)", "B": "No, because CaO has a higher coordination number (8) than MgO (6) in their crystal structures", "C": "Yes, but only at high temperatures where their thermal expansion coefficients converge", "D": "No, because the large difference in ionic radii (Ca²⁺=1.00Å vs Mg²⁺=0.72Å) prevents stable substitution" }, "correct_answer": "A", "explanation": "The correct answer is A because both CaO and MgO share the same FCC NaCl-type structure, and their lattice parameter difference (14% mismatch) is within the 15% limit for solid solution formation. Option B exploits coordination number confusion (both actually have CN=6 in NaCl structure). Option C uses a plausible-sounding but irrelevant temperature effect. Option D exaggerates the ionic radius difference impact (Hume-Rothery rules allow up to 15% difference).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 402, "question": "What are the main factors affecting grain boundary migration?", "answer": "The main factors affecting grain boundary migration rate: 1 solute atoms; 2 second-phase particles; 3 temperature; 4 orientation of grains on both sides of the grain boundary.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举和解释影响晶界迁移的主要因素，答案以文字解释和论述的形式呈现，没有提供选项或要求计算，符合简答题的特征。 | 知识层次: 题目考查对影响晶界迁移的主要因素的基本概念记忆和理解，不需要复杂的分析或综合运用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个因素（溶质原子、第二相粒子、温度、晶粒取向），但每个因素都是基础概念记忆层面的知识点，不需要复杂的分析或推理。学生只需识别并回忆这些影响晶界迁移的主要因素即可作答，属于概念解释和描述层级。", "convertible": true, "correct_option": "The main factors affecting grain boundary migration rate: 1 solute atoms; 2 second-phase particles; 3 temperature; 4 orientation of grains on both sides of the grain boundary.", "choice_question": "Which of the following correctly lists the main factors affecting grain boundary migration?", "conversion_reason": "The answer is a standard list of factors, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1 solute atoms; 2 second-phase particles; 3 temperature; 4 orientation of grains on both sides of the grain boundary", "B": "1 applied stress; 2 dislocation density; 3 stacking fault energy; 4 Burgers vector magnitude", "C": "1 cooling rate; 2 phase diagram slope; 3 thermal expansion coefficient; 4 elastic modulus", "D": "1 surface energy; 2 interface curvature; 3 diffusion coefficient; 4 vacancy concentration" }, "correct_answer": "A", "explanation": "The correct answer A lists the four primary factors that directly influence grain boundary migration kinetics. Option B cleverly substitutes dislocation-related parameters which affect dislocation motion but not grain boundary migration. Option C uses processing parameters and bulk material properties that don't directly govern boundary migration. Option D mixes valid interface terms with unrelated vacancy effects, creating a plausible but incorrect combination. Advanced AIs might select D due to recognizing some correct terms while missing the complete set.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4271, "question": "Now suppose that the density is increased to 10^10 mm^-2 by cold working. What would be the chain length of dislocations in 1000 mm^3 of material?", "answer": "for a dislocation density of 10^10 mm^-2, the chain would extend 6.2 x 10^6 miles.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解位错的链长度，答案给出了具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过给定的位错密度计算位错链的长度。虽然需要理解位错密度的概念，但计算过程直接且无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用基本公式进行简单计算，属于单一公式直接计算的难度等级。题目给出了明确的密度数值和体积，要求计算位错链长度，解题步骤简单直接，无需复杂的推理或多步骤计算。", "convertible": true, "correct_option": "6.2 x 10^6 miles", "choice_question": "If the density is increased to 10^10 mm^-2 by cold working, what would be the chain length of dislocations in 1000 mm^3 of material?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.2 x 10^6 miles", "B": "3.1 x 10^6 km", "C": "1.0 x 10^10 mm", "D": "2.5 x 10^7 light-years" }, "correct_answer": "A", "explanation": "正确答案A是通过将位错密度(10^10 mm^-2)乘以体积(1000 mm^3)得到总位错长度(10^13 mm)，再转换为英里得出。B选项数值接近但单位错误(应为英里而非公里)，利用单位混淆陷阱。C选项直接使用位错密度数值，忽略体积计算，是典型的直觉陷阱。D选项使用完全不合理的天文单位，测试对数量级的判断能力。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3953, "question": "A specimen of some metal having a rectangular cross section 11.2mm × 12.4mm is pulled in tension with a force of 31200N, which produces only elastic deformation. Given that the elastic modulus of this metal is 63 \\mathrm{GPa}, calculate the resulting strain.", "answer": "the resulting strain is 2.92 × 10^{-3}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，通过给定的力和弹性模量计算应变，答案是一个具体的数值结果。 | 知识层次: 题目涉及基本的弹性模量公式应用和简单计算，仅需一步计算即可得出结果，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用胡克定律的基本公式（应变=应力/弹性模量），并进行简单的单位换算和计算。题目提供了所有必要的数据，且解题步骤非常直接，无需组合多个公式或进行复杂的分析。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "2.92 × 10^{-3}", "choice_question": "A specimen of some metal having a rectangular cross section 11.2mm × 12.4mm is pulled in tension with a force of 31200N, which produces only elastic deformation. Given that the elastic modulus of this metal is 63 GPa, the resulting strain is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.92 × 10^{-3}", "B": "3.58 × 10^{-3}", "C": "1.46 × 10^{-3}", "D": "5.84 × 10^{-3}" }, "correct_answer": "A", "explanation": "正确答案A通过应力(force/area)除以弹性模量计算得出。B项错误地使用了剪切模量公式(应力/2×弹性模量)，利用了弹性模量与剪切模量的混淆。C项是正确值的一半，模拟了常见的计算中遗漏面积计算或模量单位的错误。D项是正确值的两倍，利用了计算中可能出现的面积或力加倍错误。这些干扰项都针对AI在单位转换和材料常数应用上的潜在弱点。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4691, "question": "(a) Calculate the fraction of atom sites that are vacant for copper (Cu) at its melting temperature of 1084°C (1357 K). Assume an energy for vacancy formation of 0.90 eV/atom.", "answer": "the fraction of atom sites that are vacant for copper at 1357 k is 4.56 × 10^-4.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（如使用能量和温度计算空缺分数）来得出具体数值结果，答案也是一个具体的计算结果（4.56 × 10^-4）。 | 知识层次: 题目要求使用给定的能量和温度计算空位分数，涉及基本公式的直接应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（空位分数计算公式）进行简单计算，无需多个步骤或复杂推理。题目提供了所有必要参数，学生只需正确代入数值即可得出答案。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "4.56 × 10^-4", "choice_question": "Calculate the fraction of atom sites that are vacant for copper (Cu) at its melting temperature of 1084°C (1357 K), assuming an energy for vacancy formation of 0.90 eV/atom. The correct fraction is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option among multiple choices in a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.56 × 10^-4", "B": "2.28 × 10^-4", "C": "9.12 × 10^-4", "D": "1.82 × 10^-3" }, "correct_answer": "A", "explanation": "正确答案A是通过Arrhenius方程计算得到的精确值。干扰项B设计为正确值的一半，利用AI可能忽略温度单位转换的认知偏差；干扰项C是正确值的两倍，针对AI可能错误应用玻尔兹曼常数的陷阱；干扰项D是正确值的四倍，针对AI可能混淆空位形成能与扩散激活能的专业直觉陷阱。所有干扰项都保持相同数量级以增加迷惑性。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2527, "question": "Explain the term: superstructure (superlattice)", "answer": "A complex lattice composed of the sublattices of each component in an ordered solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释术语\"superstructure (superlattice)\"，答案是一个文字解释和论述，没有选项、判断或计算要求。 | 知识层次: 题目考查对\"superstructure (superlattice)\"这一术语的基本定义和概念的理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目要求考生不仅知道\"超结构\"的基本定义，还需要理解其组成原理（由有序固溶体中各组分的亚晶格构成）。这超出了简单的定义记忆（等级1），但尚未达到需要阐述复杂概念体系的等级3。属于需要概念解释和描述的中间难度等级。", "convertible": true, "correct_option": "A complex lattice composed of the sublattices of each component in an ordered solid solution.", "choice_question": "Which of the following best defines the term 'superstructure (superlattice)'?", "conversion_reason": "The answer is a standard definition of the term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A complex lattice composed of the sublattices of each component in an ordered solid solution", "B": "A secondary crystalline structure formed due to surface reconstruction in thin films", "C": "A periodic arrangement of dislocations that creates a metastable lattice configuration", "D": "The dominant lattice structure that emerges when two materials form an incoherent interface" }, "correct_answer": "A", "explanation": "The correct answer is A because a superstructure (superlattice) specifically refers to the ordered arrangement of atoms in a solid solution where each component maintains its own sublattice. Option B exploits surface science intuition by describing a real but unrelated phenomenon. Option C uses dislocation terminology that sounds plausible for lattice defects but is incorrect. Option D creates confusion with interface science concepts, particularly targeting AI's tendency to overgeneralize from related terms like 'structure'.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1987, "question": "Determine whether the following dislocation reaction can proceed: $a[100]\\\\rightarrow\\\\frac{a}{2}[111]+\\\\frac{a}{2}[1\\\\overline{{{11}}}]_{\\\\circ}$.", "answer": "No. Energy condition: $\\\\sum b_{\\\\mathbb{H}}^{2}=a^{2}<\\\\sum b_{\\\\mathbb{H}}^{2}={\\\\frac{3}{2}}a^{2}$, meaning the energy increases after the reaction.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断位错反应是否能进行，答案直接给出了\"是\"或\"否\"的判断，并提供了能量条件的解释。这符合判断题的特征，即对某个陈述或现象进行真伪判断。 | 知识层次: 题目需要应用位错反应的能量条件进行判断，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于较高难度，需要综合运用位错能量计算和反应条件判断的知识。题目要求考生不仅理解位错反应的能量条件（∑b²），还需要进行多步计算和比较（计算反应前后总伯氏矢量的平方和），最后综合分析得出反应不能进行的结论。这超出了单纯概念记忆或简单计算的范畴，属于需要综合分析判断的题目类型。", "convertible": true, "correct_option": "No. Energy condition: $\\\\sum b_{\\\\mathbb{H}}^{2}=a^{2}<\\\\sum b_{\\\\mathbb{H}}^{2}={\\\\frac{3}{2}}a^{2}$, meaning the energy increases after the reaction.", "choice_question": "Determine whether the following dislocation reaction can proceed: $a[100]\\\\rightarrow\\\\frac{a}{2}[111]+\\\\frac{a}{2}[1\\\\overline{{{11}}}]_{\\\\circ}$.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The dislocation reaction $a[100]\\rightarrow\\frac{a}{2}[111]+\\frac{a}{2}[1\\overline{{{11}}}]_{\\circ}$ is energetically favorable because the total Burgers vector magnitude decreases after the reaction.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the reaction conserves the Burgers vector (a[100] = a/2[111] + a/2[1-11]), it is not energetically favorable. The energy condition shows ∑b² increases from a² to (3/2)a² after the reaction. A common mistake is assuming vector conservation alone determines favorability, ignoring the crucial energy calculation based on Burgers vector magnitudes squared.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 306, "question": "During the melt cooling and crystallization process, given the solid-liquid interfacial energy γ_sl=5×10^-6 J/cm^2 and the unit volume free energy change △Gv=2090 J/cm^3 at 900°C, calculate the energy required for the phase transition.", "answer": "The energy required for the phase transition △G* = 16πγ_sl^3/3(△Gv)^2 = 16×3.14×(5×10^-6)^3/3×(2090)^2 = 3.24×10^-19 J", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过具体计算得出的数值结果。 | 知识层次: 题目主要涉及基本公式的直接套用和简单计算，不需要多步推理或综合分析，属于对相变能量计算的基本应用。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目明确给出了所需的公式和所有必要的参数，只需要将这些数值代入公式进行简单的计算即可得到正确答案。不需要理解多个概念或进行复杂的分析，因此属于最低难度等级。", "convertible": true, "correct_option": "3.24×10^-19 J", "choice_question": "During the melt cooling and crystallization process, given the solid-liquid interfacial energy γ_sl=5×10^-6 J/cm^2 and the unit volume free energy change △Gv=2090 J/cm^3 at 900°C, the energy required for the phase transition is:", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.24×10^-19 J", "B": "6.48×10^-19 J", "C": "1.62×10^-19 J", "D": "2.59×10^-19 J" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the critical nucleus formation energy formula ΔG* = 16πγ_sl^3/3(ΔGv)^2, where γ_sl is the solid-liquid interfacial energy and ΔGv is the unit volume free energy change. Option B doubles the correct value, exploiting the common mistake of missing the 1/3 factor in the formula. Option C halves the correct value, targeting those who might confuse radius with diameter in the calculation. Option D is derived from an incorrect assumption that the energy scales linearly with γ_sl rather than its cube, appealing to intuitive but wrong simplification.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3564, "question": "For two parallel screw dislocations, when their Burgers vectors are in the same direction, the interaction force between them is (). \\n\\nA. zero B. repulsive C. attractive", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项A、B、C中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对平行螺型位错相互作用力的基本概念记忆，属于对位错基本性质的理解和记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解平行螺型位错之间的相互作用力与Burgers向量方向的关系，并进行简单辨析。题目不涉及复杂概念的区分或深度理解，但比直接记忆的定义类题目稍难。", "convertible": true, "correct_option": "B", "choice_question": "For two parallel screw dislocations, when their Burgers vectors are in the same direction, the interaction force between them is ().", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The force follows Hooke's law with a proportionality constant equal to the elastic modulus", "B": "Repulsive when dislocations are in the same slip plane, attractive otherwise", "C": "Always attractive due to dislocation line tension minimization", "D": "Repulsive when Burgers vectors are parallel, attractive when antiparallel" }, "correct_answer": "D", "explanation": "The correct answer is D because for parallel screw dislocations, the interaction force is repulsive when Burgers vectors are parallel (same direction) and attractive when antiparallel (opposite directions). This is derived from the elastic interaction energy between dislocations. Option A is a cognitive bias trap, incorrectly applying Hooke's law which governs elastic deformation, not dislocation interactions. Option B is a professional intuition trap, mixing edge dislocation behavior with screw dislocations. Option C is a multi-level verification trap, incorrectly generalizing dislocation line tension effects that are secondary to the primary elastic interaction.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3063, "question": "In which fields can ceramic materials be applied?", "answer": "Applied in insulation, wear resistance, corrosion resistance, and high-temperature resistant parts.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举陶瓷材料的应用领域，答案以文字解释和论述的形式给出，没有提供选项或要求计算，符合简答题的特征。 | 知识层次: 题目考查陶瓷材料在不同领域的应用，属于直接套用已知知识点的简单应用，不需要复杂的分析或综合。 | 难度: 在选择题中属于简单应用过程描述，题目直接考察陶瓷材料的应用领域，正确选项列举了具体的应用场景（绝缘、耐磨、耐腐蚀、耐高温部件），无需复杂分析或计算，仅需基本知识记忆即可作答。", "convertible": true, "correct_option": "Applied in insulation, wear resistance, corrosion resistance, and high-temperature resistant parts.", "choice_question": "In which fields can ceramic materials be applied?", "conversion_reason": "The answer is a standard description of the applications of ceramic materials, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermal insulation and wear-resistant coatings", "B": "Structural load-bearing components in aircraft engines", "C": "Flexible electronic displays and stretchable sensors", "D": "All of the above applications are correct" }, "correct_answer": "A", "explanation": "The correct answer is A because ceramic materials are indeed widely used in thermal insulation and wear-resistant applications due to their inherent properties. Option B is a cognitive bias trap - while ceramics are used in high-temperature engine parts, they are not typically used as primary load-bearing components due to brittleness. Option C exploits material analogy fallacy by suggesting polymer-like applications that contradict ceramic's fundamental characteristics. Option D is a multi-level verification trap that appears comprehensive but actually contains invalid applications.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2484, "question": "What is the lattice constant?", "answer": "The lengths a, b, c of the three adjacent edges in a unit cell and the angles α, β, γ between these edges determine the size and shape of the unit cell. These six parameters are called the lattice constants.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对“lattice constant”进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即晶格常数的定义和描述，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆和识别晶格常数的基本定义，属于基础概念记忆层次。正确选项直接给出了晶格常数的定义，没有涉及复杂的概念体系或需要深入理解的内容，因此属于最简单的难度等级。", "convertible": true, "correct_option": "The lengths a, b, c of the three adjacent edges in a unit cell and the angles α, β, γ between these edges determine the size and shape of the unit cell. These six parameters are called the lattice constants.", "choice_question": "Which of the following best defines the lattice constant?", "conversion_reason": "The answer is a standard definition of the term 'lattice constant', which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The lengths a, b, c of the three adjacent edges in a unit cell and the angles α, β, γ between these edges determine the size and shape of the unit cell", "B": "The minimum distance between two adjacent lattice points in a crystal structure", "C": "A constant value representing the average atomic spacing in any crystalline material", "D": "The ratio of unit cell volume to the number of atoms in the basis for a given crystal structure" }, "correct_answer": "A", "explanation": "The lattice constants are the six parameters (a, b, c, α, β, γ) that fully define the unit cell geometry. Option B is incorrect because it describes only one aspect (nearest neighbor distance) but misses the angular parameters. Option C is a common oversimplification that ignores the directional dependence and unit cell geometry. Option D describes a derived parameter (atomic packing factor) rather than fundamental lattice constants. Advanced AI might choose B due to its partial correctness, or C due to its deceptive simplicity.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1703, "question": "For two types of diffusion with activation energies of E1= 83.7 kJ/mol and E2=251 kJ/mol, how does the diffusion rate change when the temperature increases from 25°C to 600°C?", "answer": "From D=D0exp(-Q/RT): when the temperature increases from 298K to 873K, the diffusion rate D increases by 4.6×10^9 and 9.5×10^28 times, respectively.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过公式计算扩散速率的变化，答案给出了具体的数值计算结果，符合计算题的特征。 | 知识层次: 题目需要应用扩散速率公式进行多步计算，涉及不同温度下的比较和指数运算，需要理解公式中各参数的意义并进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于高难度题目，需要综合运用扩散速率公式进行多步复杂计算。题目要求计算两种不同激活能情况下温度变化对扩散速率的影响，涉及指数函数的复杂运算（从298K到873K的9.5×10^28倍变化计算），需要准确理解并应用Arrhenius方程，同时处理两个不同激活能系统的对比分析。这种需要处理多变量、进行指数级计算并比较不同系统行为的题目，在选择题型中属于最复杂的类型之一。", "convertible": true, "correct_option": "The diffusion rate increases by 4.6×10^9 and 9.5×10^28 times, respectively.", "choice_question": "For two types of diffusion with activation energies of E1= 83.7 kJ/mol and E2=251 kJ/mol, how does the diffusion rate change when the temperature increases from 25°C to 600°C?", "conversion_reason": "The answer is a specific numerical result, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diffusion rate increases by 4.6×10^9 and 9.5×10^28 times, respectively", "B": "The diffusion rate increases by 2.3×10^6 and 1.7×10^18 times, respectively", "C": "The diffusion rate decreases due to thermal expansion effects", "D": "Both diffusion rates increase by the same factor of 1.2×10^12 times" }, "correct_answer": "A", "explanation": "The correct answer A uses the Arrhenius equation properly considering the exponential temperature dependence. Option B miscalculates the pre-exponential factor. Option C exploits the common misconception about thermal expansion dominating diffusion. Option D creates a false symmetry by ignoring the different activation energies.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4164, "question": "Match the luminescence characteristics with their descriptions.\nReemission of photons occurs in much less than one second after excitation.\n- Phosphorescence\n- Fluorescence\nReemission of photons occurs in more than one second after excitation.\n- Fluorescence\n- Phosphorescence", "answer": "Fluorescence involves reemission of photons in much less than one second after excitation; while phosphorescence involves reemission of photons in more than one second after excitation.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的选项中选择正确的匹配项，即将发光特性与描述进行配对。答案部分也明确给出了选项之间的对应关系，符合选择题的特征。 | 知识层次: 题目考查荧光和磷光的基本定义和区别，属于基础概念的记忆和理解 | 难度: 在选择题型中，该题目属于概念理解和简单辨析的难度等级。虽然题目涉及两个不同的发光现象（荧光和磷光），但只需要考生理解并区分两者的基本定义特征（光子再发射的时间差异）。不需要复杂的分析或深度理解多个概念之间的关系，属于基础概念记忆和简单辨析的范畴。", "convertible": true, "correct_option": "Fluorescence involves reemission of photons in much less than one second after excitation; while phosphorescence involves reemission of photons in more than one second after excitation.", "choice_question": "Match the luminescence characteristics with their descriptions.", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provides a clear distinction between the two options, making it suitable for conversion to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress for slip in FCC metals is primarily determined by the Peierls-Nabarro stress", "B": "Twinning is the dominant deformation mechanism in pure aluminum at room temperature", "C": "The Hall-Petch relationship predicts decreasing yield strength with decreasing grain size in polycrystalline metals", "D": "Dislocation climb is the primary mechanism for plastic deformation in BCC metals at 0.5Tm" }, "correct_answer": "A", "explanation": "Correct answer (A) is actually a common misconception - while Peierls-Nabarro stress is important for covalent/ionic crystals, FCC metals' CRSS is mainly determined by dislocation interactions. Option B exploits the intuitive but wrong association of 'soft' metals with twinning. Option C reverses the actual Hall-Petch relationship direction. Option D mixes up temperature regimes - climb becomes important at high temperatures (>0.5Tm). These options target AI's tendency to rely on surface-level material science correlations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1107, "question": "Indicate which plane among (100), (110), and (111) in a face-centered cubic crystal is the close-packed plane", "answer": "The (111) plane has the highest packing density (0.90), so the close-packed plane in a face-centered cubic crystal is the (111) plane", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的平面选项（100）、（110）和（111）中选择一个密排面，属于从多个选项中选择正确答案的类型 | 知识层次: 题目考查对立方晶系中密排面的基本概念记忆，仅需识别(111)面为面心立方结构中的密排面，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要记忆和理解面心立方晶体中不同晶面的堆垛密度，但题目直接给出了正确选项，且只需比较(100)、(110)、(111)三个晶面的堆垛密度即可得出答案。不需要复杂的分析或计算，属于基础概念理解和简单辨析的范畴。", "convertible": true, "correct_option": "(111) plane", "choice_question": "Which plane among (100), (110), and (111) in a face-centered cubic crystal is the close-packed plane?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provides a clear correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(100) plane due to its highest planar density in simple cubic crystals", "B": "(110) plane because it contains the closest-packed direction <110>", "C": "(111) plane with its hexagonal arrangement of atoms", "D": "All three planes are equally close-packed in FCC crystals" }, "correct_answer": "C", "explanation": "The correct answer is C because the (111) plane in FCC crystals has the highest planar atomic density with a hexagonal close-packed arrangement. Option A exploits confusion with simple cubic crystals where (100) is indeed most dense. Option B uses the true fact about <110> direction packing to mislead about plane packing. Option D creates ambiguity by suggesting equivalence, which is false but plausible given FCC's high symmetry.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4325, "question": "What is the distinction between hypoeutectoid and hypereutectoid steels?", "answer": "A \"hypoeutectoid\" steel has a carbon concentration less than the eutectoid; on the other hand, a \"hypereutectoid\" steel has a carbon content greater than the eutectoid.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释hypoeutectoid和hypereutectoid steels的区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对hypoeutectoid和hypereutectoid steels的基本定义和分类的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生区分并比较两个相关但不同的术语（hypoeutectoid和hypereutectoid steels），并理解它们与碳浓度的关系。这比单纯记忆一个定义（等级1）要求更高，但不需要复杂的分析或阐述（等级3）。", "convertible": true, "correct_option": "A \"hypoeutectoid\" steel has a carbon concentration less than the eutectoid; on the other hand, a \"hypereutectoid\" steel has a carbon content greater than the eutectoid.", "choice_question": "What is the distinction between hypoeutectoid and hypereutectoid steels?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hypoeutectoid steels contain less than 0.76% carbon and form proeutectoid ferrite, while hypereutectoid steels contain more than 0.76% carbon and form proeutectoid cementite", "B": "Hypoeutectoid steels have higher toughness due to ferrite dominance, while hypereutectoid steels show greater hardness from cementite networks", "C": "The distinction depends on cooling rate rather than composition, with hypoeutectoid forming at slower rates and hypereutectoid at faster rates", "D": "Hypoeutectoid steels are always below 0.2% carbon for weldability, while hypereutectoid steels exceed 1.0% carbon for tool applications" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines the carbon content boundary (0.76%) and corresponding microstructural phases. Option B describes mechanical properties rather than the fundamental distinction. Option C incorrectly shifts the criterion to cooling rate, exploiting a common processing misconception. Option D introduces arbitrary carbon thresholds for applications, creating a plausible but incorrect definition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 379, "question": "In the diamond structure, carbon is connected by (5) bonds, and the coordination number is (6).", "answer": "(5) covalent; (6) 4", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写特定术语（covalent和4）来补全句子，属于需要简短文字回答的简答题类型，而非选择、判断或计算题。 | 知识层次: 题目考查金刚石结构中碳原子之间的键合类型和配位数的基本概念记忆，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅考察对金刚石结构中碳原子键合类型和配位数的记忆性知识，无需复杂的概念解释或分析。正确选项直接对应基础概念记忆，解题步骤简单明了。", "convertible": true, "correct_option": "covalent; 4", "choice_question": "In the diamond structure, carbon is connected by bonds, and the coordination number is:", "conversion_reason": "The original short answer question has a specific and standard answer, which can be converted into a multiple-choice format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "covalent; 4", "B": "metallic; 12", "C": "ionic; 6", "D": "van der Waals; 8" }, "correct_answer": "A", "explanation": "The correct answer is A because in diamond structure, carbon atoms form covalent bonds with 4 neighboring atoms in a tetrahedral arrangement. Option B is designed to exploit the common metallic crystal structure misconception. Option C targets confusion with ionic crystals like NaCl. Option D creates a trap by combining an incorrect bond type with the coordination number of body-centered cubic structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2611, "question": "What are isotopes?", "answer": "Substances that occupy the same position in the periodic table, although their masses are different, yet their chemical properties are the same, are called isotopes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述同位素的定义，答案提供了详细的文字描述，符合简答题的特征。 | 知识层次: 题目考查同位素的基本定义和特性，属于基础概念的记忆和理解范畴，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别同位素的基本定义，属于最基础的概念记忆层次。正确选项直接给出了同位素的明确定义，无需进行任何解释、比较或分析，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Substances that occupy the same position in the periodic table, although their masses are different, yet their chemical properties are the same, are called isotopes.", "choice_question": "Which of the following best defines isotopes?", "conversion_reason": "The answer is a standard definition of isotopes, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Substances that occupy the same position in the periodic table, although their masses are different, yet their chemical properties are the same", "B": "Elements with identical atomic numbers but varying neutron counts, resulting in different nuclear properties while maintaining identical electron configurations", "C": "Atoms of the same element with different numbers of neutrons, leading to variations in both physical and chemical properties", "D": "Different crystalline forms of the same element where atomic arrangement differs but chemical composition remains constant" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines isotopes as variants of the same element (same position in periodic table) with different masses (due to neutron variation) but identical chemical properties. Option B is a near-perfect trap as it correctly describes isotopes but misleadingly suggests different nuclear properties affect chemical behavior. Option C is a common misconception that isotopes show chemical property variations. Option D describes allotropes, not isotopes, exploiting confusion between atomic and crystalline structure concepts.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3787, "question": "Which of these alloying elements is expected to have unlimited solid solubility in copper? (a) Au (b) Mn (c) Sr (d) Si (e) Co", "answer": "(a)", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从多个选项中选择一个正确答案，具有明确的选择项和单一正确答案特征 | 知识层次: 题目考查对固溶度概念的理解以及合金元素与铜的相互作用，需要综合分析原子尺寸、电负性、晶体结构等因素来判断固溶度，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，需要综合运用材料科学中的固溶度概念、Hume-Rothery规则以及元素周期表知识。解题过程涉及多步分析：1) 理解铜的晶体结构(FCC) 2) 掌握Hume-Rothery规则的四个条件(原子尺寸差、电负性、价电子数、晶体结构) 3) 对各选项元素进行系统比较。特别是需要判断金(Au)与铜的相似性，这需要较深入的材料学知识而非简单记忆。虽然题目形式是选择题，但解题所需的综合分析过程使其难度高于基础概念题。", "convertible": true, "correct_option": "Au", "choice_question": "Which of these alloying elements is expected to have unlimited solid solubility in copper?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Au", "B": "Ni", "C": "Zn", "D": "Cr" }, "correct_answer": "A", "explanation": "Au has unlimited solid solubility in Cu due to their similar atomic radii, crystal structure (both FCC), and electronegativity. Ni (B) is a strong trap with its similar FCC structure but limited solubility due to differing electronic structures. Zn (C) forms extensive solid solutions but shows deviation from ideal behavior. Cr (D) has BCC structure causing severe lattice mismatch with Cu's FCC structure, making it the most obvious wrong choice that may trap AI models relying on simple crystal structure matching.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4147, "question": "Which of the following characteristics are displayed by hard magnetic materials in terms of magnetization and demagnetization field requirements?", "answer": "Magnetization and demagnetization require relatively high applied fields.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对硬磁材料在磁化和退磁过程中所需磁场特性的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题中属于中等偏下难度，需要理解硬磁材料的基本特性（磁化和退磁需要较高外场）这一概念，但不需要进行复杂的概念比较或分析。属于基础概念理解和简单辨析层次。", "convertible": true, "correct_option": "Magnetization and demagnetization require relatively high applied fields.", "choice_question": "Which of the following characteristics are displayed by hard magnetic materials in terms of magnetization and demagnetization field requirements?", "conversion_reason": "The original question is already in a multiple-choice format and can be directly converted to a single-choice question by selecting the correct option from the given choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Magnetization and demagnetization require relatively high applied fields", "B": "Exhibit low coercivity and high magnetic permeability", "C": "Demagnetization occurs spontaneously at room temperature", "D": "Magnetization direction easily rotates with small applied fields" }, "correct_answer": "A", "explanation": "Hard magnetic materials are characterized by high coercivity, meaning they require strong fields for both magnetization and demagnetization (A). Option B incorrectly describes soft magnetic materials. Option C exploits the misconception that hard magnets might lose magnetization easily, while D describes behavior opposite to hard magnets' high anisotropy energy.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2957, "question": "The main reason why it is difficult to form a single-phase structure in polymer alloys is that the alloy has (A) smaller mixing entropy (B) opposite to (A) (C) smaller mixing heat", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（A、B、C）中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对聚合物合金形成单相结构困难原因的基础概念记忆，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（聚合物合金的单相结构形成困难的主要原因），但需要考生理解并区分\"混合熵\"和\"混合热\"这两个概念。正确选项A（较小的混合熵）需要考生对聚合物合金的基本原理有一定理解，而不仅仅是简单的概念识别。不过题目没有涉及更复杂的分析或多概念综合比较，因此难度属于等级2。", "convertible": true, "correct_option": "A", "choice_question": "The main reason why it is difficult to form a single-phase structure in polymer alloys is that the alloy has", "conversion_reason": "The original question is already in a multiple-choice format, which can be directly used as a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The entropic contribution to mixing is significantly reduced due to the large molecular weight of polymers", "B": "The high viscosity of molten polymers prevents adequate diffusion for homogeneous mixing", "C": "Most polymer pairs exhibit positive heat of mixing due to incompatible solubility parameters", "D": "Crystallinity in semi-crystalline polymers creates thermodynamic barriers to single-phase formation" }, "correct_answer": "A", "explanation": "The correct answer is A because the primary thermodynamic limitation in polymer mixing is the drastically reduced combinatorial entropy of mixing for long-chain molecules compared to small molecules. While options B, C, and D describe real phenomena, they are secondary effects: B describes a kinetic rather than thermodynamic limitation, C is true for many but not all polymer pairs, and D only applies to crystalline polymers. Advanced AI systems might incorrectly select C due to overemphasis on solubility parameter theory or D due to overgeneralization from crystalline material behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2517, "question": "Explain the term: alloy", "answer": "A material formed by the chemical bonding of a metal with one or more other elements.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释术语\"alloy\"，答案是一个文字解释和论述，没有选项、判断或计算的要求 | 知识层次: 题目考查基本概念的记忆和理解，即合金的定义，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别合金的基本定义，属于最基础的概念记忆层次。题目不涉及任何解释、分析或比较过程，只需直接回忆并选择正确的定义描述。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "A material formed by the chemical bonding of a metal with one or more other elements.", "choice_question": "Which of the following best defines the term 'alloy'?", "conversion_reason": "The answer is a standard definition of a term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A material formed by the chemical bonding of a metal with one or more other elements", "B": "A mixture where the primary component is always iron", "C": "Any homogeneous combination of two or more metals in solid state", "D": "A composite material with enhanced mechanical properties through phase dispersion" }, "correct_answer": "A", "explanation": { "correct": "This is the precise scientific definition of an alloy, emphasizing the chemical bonding aspect which distinguishes it from simple mixtures.", "A_trap": "Uses the technically accurate 'chemical bonding' phrasing that requires deep materials science knowledge to recognize as correct.", "B_trap": "Exploits the common association of alloys with steel (iron-based), creating a strong but incorrect intuitive link.", "C_trap": "Appears correct by including key terms like 'homogeneous' and 'metals', but fails by excluding non-metal alloying elements and implying only solid state.", "D_trap": "Mimics advanced materials terminology ('phase dispersion') while actually describing metal matrix composites, not alloys." }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3947, "question": "If an increased steady-state flow rate of O2 (oxygen molecules per second) to the cornea is desired, is increasing the contact lens thickness likely to be useful? Note: the flow rate is equal to product of the diffusion flux and an area of interest through which diffusion occurs.", "answer": "If the contact lens thickness is increased and all other factors are preserved, the concentration gradient decrease and the oxygen diffusion flux should decrease.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案提供了详细的解释和推理过程，而不是简单的选择或判断。 | 知识层次: 题目需要理解扩散通量的概念，并分析厚度变化对浓度梯度和扩散通量的影响，涉及多步推理和概念关联，但不需要复杂的综合或创新应用。 | 难度: 在选择题中属于中等难度，需要理解扩散通量、浓度梯度以及接触镜厚度之间的关系，并进行综合分析。题目要求考生能够将多个概念关联起来，并预测厚度变化对氧气传输的影响，但不需要进行复杂的多角度分析或深度关联性分析。", "convertible": true, "correct_option": "No, because increasing the contact lens thickness decreases the oxygen diffusion flux.", "choice_question": "If an increased steady-state flow rate of O2 (oxygen molecules per second) to the cornea is desired, is increasing the contact lens thickness likely to be useful? Note: the flow rate is equal to the product of the diffusion flux and an area of interest through which diffusion occurs.", "conversion_reason": "The answer is a clear and concise explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing plausible options, with the given answer being the correct one.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because thicker lenses have greater surface area for oxygen adsorption", "B": "Yes, because increased thickness provides more diffusion pathways through the polymer matrix", "C": "No, because increasing thickness decreases the concentration gradient driving diffusion", "D": "No, because thicker lenses increase the diffusion path length while keeping flux constant" }, "correct_answer": "C", "explanation": "The correct answer is C because according to Fick's first law, diffusion flux is inversely proportional to thickness when maintaining a constant concentration difference. Option A exploits surface area misconception (adsorption vs diffusion). Option B misleads by suggesting non-existent additional pathways. Option D contains partial truth but incorrectly states flux remains constant. Advanced AI might choose D due to its plausible-sounding but subtly wrong conclusion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1814, "question": "In the sintering process, the mass transfer method that only changes the pore shape without causing shrinkage of the green body is a. diffusion mass transfer b. flow mass transfer c. evaporation-condensation mass transfer d. grain boundary diffusion", "answer": "c", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从四个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查烧结过程中质量传递方式的基本概念记忆，特别是蒸发-凝聚质量传递的特点，属于基础概念的记忆和理解。 | 难度: 该题目属于基础概念记忆层次，要求考生识别烧结过程中不同传质方式的特点。虽然需要理解蒸发-凝聚传质与其他传质方式的区别，但题目直接给出了关键特征（不引起收缩），属于概念理解和简单辨析的难度级别。在选择题型中，不需要复杂的分析过程，只需将特征与选项对应即可。", "convertible": true, "correct_option": "c. evaporation-condensation mass transfer", "choice_question": "In the sintering process, the mass transfer method that only changes the pore shape without causing shrinkage of the green body is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "surface diffusion", "B": "viscous flow", "C": "evaporation-condensation", "D": "volume diffusion" }, "correct_answer": "C", "explanation": "The correct answer is C (evaporation-condensation) because this mass transfer mechanism only redistributes material between surfaces without causing macroscopic shrinkage. A (surface diffusion) is a strong distractor as it's also a surface transport mechanism, but it can lead to neck growth and slight shrinkage. B (viscous flow) is designed to exploit the common misconception about glass sintering behavior. D (volume diffusion) is included to test if the model can distinguish between bulk and surface transport mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1572, "question": "8. Dynamic recrystallization", "answer": "The phenomenon where deformation and recrystallization occur simultaneously above the recrystallization temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Dynamic recrystallization\"这一现象进行文字解释和论述，答案是一个定义性的文字描述，符合简答题的特征。 | 知识层次: 题目考查动态再结晶这一基本概念的定义，属于基础概念的记忆和理解层面，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别动态再结晶的基本定义，属于最基础的概念记忆层次。题目直接给出了定义描述作为正确选项，无需进行复杂的概念比较或分析，因此属于难度等级1。", "convertible": true, "correct_option": "The phenomenon where deformation and recrystallization occur simultaneously above the recrystallization temperature.", "choice_question": "What is dynamic recrystallization?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phenomenon where deformation and recrystallization occur simultaneously above the recrystallization temperature", "B": "The process of grain refinement through repeated cold working and annealing cycles below the recrystallization temperature", "C": "The spontaneous formation of new grains during high-temperature deformation without prior dislocation accumulation", "D": "The transformation of deformed grains into equiaxed grains during post-deformation heat treatment" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines dynamic recrystallization as concurrent deformation and recrystallization above the recrystallization temperature. Option B describes static recrystallization, exploiting the common confusion between dynamic and static processes. Option C uses a plausible-sounding but incorrect mechanism (spontaneous formation) to trap those with incomplete understanding. Option D describes conventional recrystallization, testing the ability to distinguish between in-situ and post-process phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4284, "question": "Briefly explain why small-angle grain boundaries are not as effective in interfering with the slip process as are high-angle grain boundaries.", "answer": "Small-angle grain boundaries are not as effective in interfering with the slip process as are high-angle grain boundaries because there is not as much crystallographic misalignment in the grain boundary region for small-angle, and therefore not as much change in slip direction.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求简要解释小角度晶界在干扰滑移过程中不如大角度晶界有效的原因，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释小角度晶界和大角度晶界在阻碍滑移过程中的不同效果，涉及晶界结构对滑移过程的影响，需要理解晶界角度与滑移方向变化之间的关系，属于概念关联和综合分析层次。 | 难度: 在选择题中属于中等难度，需要理解晶界角度对滑移过程的影响，并进行概念比较分析。题目要求考生理解小角度晶界和高角度晶界在晶体结构错排程度上的差异，以及这种差异如何影响滑移过程。虽然不需要多步计算，但需要对材料科学中的晶界概念有较好的掌握，并能进行综合分析。", "convertible": true, "correct_option": "Small-angle grain boundaries are not as effective in interfering with the slip process as are high-angle grain boundaries because there is not as much crystallographic misalignment in the grain boundary region for small-angle, and therefore not as much change in slip direction.", "choice_question": "Why are small-angle grain boundaries not as effective in interfering with the slip process as are high-angle grain boundaries?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dislocation density in small-angle boundaries is too low to effectively pin slip dislocations", "B": "The elastic strain fields in small-angle boundaries are insufficient to block dislocation motion", "C": "There is not enough crystallographic misalignment to significantly alter slip directions", "D": "Small-angle boundaries allow for continuous slip plane transmission across the boundary" }, "correct_answer": "C", "explanation": "The correct answer is C because small-angle grain boundaries have minimal crystallographic misorientation, resulting in insufficient change in slip direction to effectively interfere with dislocation motion. Option A is a cognitive bias trap - while dislocation density is relevant, it's not the primary reason. Option B exploits confusion between elastic strain fields (which exist) and their actual effect. Option D is a professional intuition trap, as it seems plausible but ignores that some slip transmission still occurs even in high-angle boundaries.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4034, "question": "For a congruent phase transformations there are (a) no composition alterations.(b) compositional alterations.", "answer": "(a) no composition alterations", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从两个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对“congruent phase transformations”这一基本概念的记忆和理解，特别是其定义中关于成分变化的特点。这属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即“共晶相变”的定义特征。题目直接考察学生是否记住“共晶相变没有成分改变”这一基本事实，无需理解或辨析其他复杂概念。属于最简单的概念识别层级。", "convertible": true, "correct_option": "no composition alterations", "choice_question": "For a congruent phase transformations there are:", "conversion_reason": "The original question is already in a multiple-choice format with two options, and it can be directly converted to a single-choice question by keeping the question stem and identifying the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No change in crystal structure symmetry", "B": "Simultaneous change in both composition and crystal structure", "C": "Only change in composition while maintaining the same crystal structure", "D": "A discontinuous change in free energy with temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because congruent phase transformations occur without any change in the symmetry of the crystal structure. Option B is a cognitive bias trap, combining two incorrect changes that might seem plausible together. Option C exploits the common confusion between congruent and diffusion-based transformations. Option D is a professional intuition trap, as it describes a characteristic of first-order transitions rather than congruent transformations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 671, "question": "How does solute concentration affect the diffusion coefficient?", "answer": "In many solid solution alloys, the diffusion coefficient of the solute increases with increasing concentration.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释溶质浓度如何影响扩散系数，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目涉及扩散系数与溶质浓度关系的理解，需要将扩散理论的基本概念与实际合金体系中的现象关联起来进行分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解扩散系数与溶质浓度的关系，并能够综合分析固体溶液合金中的扩散行为。题目涉及中等应用层次的知识，要求考生将多个概念关联起来进行判断，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "In many solid solution alloys, the diffusion coefficient of the solute increases with increasing concentration.", "choice_question": "How does solute concentration affect the diffusion coefficient in many solid solution alloys?", "conversion_reason": "The answer is a standard statement that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diffusion coefficient decreases exponentially with solute concentration due to lattice strain effects", "B": "The diffusion coefficient increases linearly with solute concentration up to the solubility limit", "C": "The diffusion coefficient shows a minimum at intermediate concentrations due to competing vacancy mechanisms", "D": "The diffusion coefficient becomes concentration-independent above 5 at.% solute due to percolation threshold effects" }, "correct_answer": "B", "explanation": "Correct answer B reflects the experimentally observed linear increase in many alloy systems due to enhanced vacancy-solute interactions. Option A exploits the common misconception about lattice strain always retarding diffusion. Option C creates a false intuition about competing mechanisms. Option D uses a real concept (percolation threshold) but misapplies it to diffusion behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4453, "question": "What is crystallization?", "answer": "Crystallization is the process whereby a glass material is caused to transform to a crystalline solid, usually as a result of a heat treatment.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"crystallization\"进行定义和解释，需要文字论述而非选择、判断或计算 | 知识层次: 题目考查基本概念的记忆和理解，即结晶化的定义和基本原理，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别结晶化的基本定义，属于最基础的概念记忆层次。题目正确选项直接给出了结晶化的定义，不需要任何解释、分析或比较过程，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Crystallization is the process whereby a glass material is caused to transform to a crystalline solid, usually as a result of a heat treatment.", "choice_question": "Which of the following best describes crystallization?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct option and plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A spontaneous process where atoms arrange into a periodic structure upon cooling below the melting point", "B": "The process where a glass material transforms to a crystalline solid through heat treatment", "C": "The alignment of polymer chains under mechanical stress to form ordered domains", "D": "The precipitation of solute atoms from a supersaturated solid solution" }, "correct_answer": "B", "explanation": "The correct answer is B because crystallization specifically refers to the transformation from an amorphous (glass) to crystalline state through heat treatment. Option A describes normal solidification, not crystallization. Option C describes polymer orientation, not true crystallization. Option D describes precipitation hardening, a different phenomenon. The distractors exploit common confusions between related but distinct material processes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 47, "question": "Into which categories can silicate crystals be classified?", "answer": "Silicate crystals can be specifically classified into five categories: island, group, chain, layer, and framework.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对硅酸盐晶体进行分类，并需要文字解释和论述，答案提供了具体的分类名称，符合简答题的特征 | 知识层次: 题目考查对硅酸盐晶体分类的基本概念记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆硅酸盐晶体的五种基本分类（岛状、群状、链状、层状和架状），属于基础概念的直接回忆。不需要解释或分析，只需识别正确选项，因此属于最简单的难度等级。", "convertible": true, "correct_option": "island, group, chain, layer, and framework", "choice_question": "Into which categories can silicate crystals be classified?", "conversion_reason": "The answer is a standard list of categories, which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "island, group, chain, layer, and framework", "B": "ionic, covalent, metallic, and molecular", "C": "primary, secondary, tertiary, and quaternary", "D": "simple cubic, body-centered cubic, face-centered cubic, and hexagonal close-packed" }, "correct_answer": "A", "explanation": "The correct answer is A because silicate crystals are classified based on their structural arrangement of SiO4 tetrahedra into island (isolated), group (paired), chain (linear), layer (sheet), and framework (3D network) silicates. Option B is incorrect as it lists bonding types rather than silicate classifications, exploiting the cognitive bias of confusing structural classification with bonding types. Option C is incorrect as it mimics protein structure terminology, creating a professional intuition trap for those familiar with biochemistry. Option D is incorrect as it provides common crystal packing arrangements, exploiting the multi-level verification trap by presenting real but irrelevant crystallographic concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3781, "question": "Based on Hume-Rothery's conditions, would the system Nb-W be expected to display unlimited solid solubility? Explain.", "answer": "No", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求基于Hume-Rothery条件进行解释说明，答案需要文字论述而非简单选择或判断，符合简答题的特征 | 知识层次: 题目要求基于Hume-Rothery规则分析Nb-W体系的固溶度问题，需要理解并应用多个条件（原子尺寸、电负性、价电子浓度、晶体结构）进行综合分析，属于中等应用层次。虽然不涉及复杂计算，但需要对多个概念进行关联判断。 | 难度: 在选择题中属于中等难度，需要理解Hume-Rothery规则中的多个条件（如原子尺寸、电负性、晶体结构等），并将这些概念应用于Nb-W系统的分析。虽然题目给出了正确选项，但学生仍需进行多步概念关联和综合分析才能得出正确结论。", "convertible": true, "correct_option": "No", "choice_question": "Based on Hume-Rothery's conditions, would the system Nb-W be expected to display unlimited solid solubility?", "conversion_reason": "The answer is a standard term (No) and the question can be converted to a multiple-choice format by providing options such as 'Yes' and 'No'.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because both elements are BCC with similar atomic radii (Nb: 1.43Å, W: 1.41Å)", "B": "No, due to significant differences in their electronegativity values (Nb: 1.6, W: 2.36)", "C": "Yes, since both are refractory metals with high melting points (>2400°C)", "D": "No, because their crystal structures are incompatible (Nb: BCC, W: FCC)" }, "correct_answer": "B", "explanation": "Correct answer is B because while atomic size factor is favorable, the large electronegativity difference (ΔEN=0.76) violates Hume-Rothery's condition for chemical affinity. Option A is a cognitive bias trap using correct radius data but ignoring electronegativity. Option C exploits professional intuition about refractory metals' similarity. Option D contains a factual error (W is actually BCC) to catch those with imperfect crystal structure knowledge.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 630, "question": "What final heat treatment process can be used for decorative wires for indoor electric lights after processing? Why?", "answer": "Decorative wires for indoor electric lights need to be easily deformable and have high electrical conductivity. Recrystallization annealing can be used to soften them and achieve high electrical conductivity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么特定的热处理工艺适用于装饰性电线，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解材料性能要求（易变形性和高导电性）与热处理工艺（再结晶退火）之间的关系，属于概念关联和综合分析层次。虽然不涉及复杂计算，但需要对材料性能和处理工艺有较深入的理解和应用能力。 | 难度: 在选择题中属于中等难度，题目要求理解装饰性电线所需的性能（易变形性和高导电性）以及再结晶退火的作用（软化和提高导电性）。需要将材料性能与热处理工艺关联起来，进行综合分析，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "Recrystallization annealing can be used to soften them and achieve high electrical conductivity.", "choice_question": "What final heat treatment process can be used for decorative wires for indoor electric lights after processing to ensure they are easily deformable and have high electrical conductivity?", "conversion_reason": "The answer is a standard term and concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization annealing at 0.5Tm for 1 hour", "B": "Precipitation hardening at 300°C for 2 hours", "C": "Martensitic quenching followed by tempering", "D": "Normalizing at 900°C with air cooling" }, "correct_answer": "A", "explanation": "Recrystallization annealing (A) is correct because it eliminates work hardening effects while maintaining high conductivity. Precipitation hardening (B) is a strong distractor as it's commonly used for strengthening conductive alloys, but would reduce deformability. Martensitic treatment (C) exploits the common association of quenching with conductivity enhancement, but is inappropriate for decorative wires. Normalizing (D) appears plausible for softening but would coarsen grains excessively. The key is recognizing that decorative wires require both softness (for shaping) and conductivity, which only recrystallization provides.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1937, "question": "It is known that atomic radius is related to crystal structure. When the coordination number decreases, how does the atomic radius change? Why?", "answer": "The radius contracts. If the radius remains unchanged, a decrease in coordination number would cause an increase in crystal volume. To minimize volume change, the atomic radius will contract.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要文字解释和论述原子半径如何变化及其原因，答案提供了详细的解释而非简单的选择或判断。 | 知识层次: 题目需要理解原子半径与配位数之间的关系，并解释其变化原因，涉及概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解原子半径与配位数之间的关系，并能够解释为什么半径会收缩。题目要求考生不仅知道现象，还要理解背后的原理（最小化体积变化），这涉及中等应用层次的知识点掌握和综合分析能力。", "convertible": true, "correct_option": "The radius contracts.", "choice_question": "When the coordination number decreases, how does the atomic radius change?", "conversion_reason": "The answer is a standard and concise statement that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit the multiple-choice format by focusing on the change in atomic radius.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The radius contracts due to reduced electron shielding", "B": "The radius expands because of decreased interatomic repulsion", "C": "Remains unchanged as it's an intrinsic property", "D": "First expands then contracts due to bond angle distortion" }, "correct_answer": "A", "explanation": "The correct answer is A because decreased coordination number reduces electron cloud overlap, leading to contraction. Option B exploits the common misconception about reduced repulsion causing expansion. Option C targets the fundamental misunderstanding of atomic radius being context-independent. Option D creates a complex multi-step reasoning trap that seems plausible for certain structural transformations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 407, "question": "Solid solution", "answer": "Solid solution: When foreign components enter the crystal structure, occupying part of the host crystal phase's lattice sites or interstitial positions, while still maintaining a single crystal phase, such a crystal is called a solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Solid solution\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对固溶体这一基本概念的定义和特征的理解和记忆，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项对“solid solution”的定义进行了较为详细的解释，包括外来组分进入晶体结构的方式（占据晶格位点或间隙位置）以及保持单晶相的特性。这要求考生不仅记住定义，还需要理解其中的关键要素。因此，相较于仅需简单记忆基本定义的题目（等级1），该题目的难度稍高，属于等级2。", "convertible": true, "correct_option": "When foreign components enter the crystal structure, occupying part of the host crystal phase's lattice sites or interstitial positions, while still maintaining a single crystal phase, such a crystal is called a solid solution.", "choice_question": "Which of the following correctly defines a solid solution?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by presenting the definition as the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When foreign components enter the crystal structure, occupying part of the host crystal phase's lattice sites or interstitial positions, while still maintaining a single crystal phase, such a crystal is called a solid solution.", "B": "A homogeneous mixture of two or more metals where the secondary component forms distinct crystalline regions within the primary matrix.", "C": "A metastable phase formed by rapid quenching that exhibits composition gradients across grain boundaries.", "D": "Any polycrystalline material containing solute atoms segregated at dislocations or grain boundaries." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a solid solution as a single-phase system where solute atoms occupy either substitutional or interstitial sites in the host lattice. Option B incorrectly describes a two-phase system with distinct crystalline regions. Option C refers to a non-equilibrium phase with composition gradients, not a true solid solution. Option D describes solute segregation phenomena in polycrystalline materials, which is a local effect rather than a homogeneous solid solution. The distractors exploit common misconceptions about phase homogeneity, equilibrium conditions, and microstructural features in alloy systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1392, "question": "What are the adverse effects of the work hardening characteristics of metals on the use of metal materials?", "answer": "It makes the metal difficult to undergo further cold plastic deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释金属加工硬化特性的不利影响，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释金属加工硬化特性对金属材料使用的不利影响，涉及对加工硬化概念的理解及其在实际应用中的影响分析。虽然需要一定的概念记忆，但更侧重于将概念与实际应用场景关联起来，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解金属加工硬化的特性及其对材料使用的影响，并进行综合分析。题目要求考生将金属的加工硬化特性与冷塑性变形的难度联系起来，这涉及多个概念的关联和一定程度的综合分析能力。", "convertible": true, "correct_option": "It makes the metal difficult to undergo further cold plastic deformation.", "choice_question": "What is one of the adverse effects of the work hardening characteristics of metals on the use of metal materials?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It makes the metal difficult to undergo further cold plastic deformation", "B": "It significantly reduces the electrical conductivity of the metal", "C": "It causes anisotropic thermal expansion during heating", "D": "It increases the solubility of interstitial elements in the lattice" }, "correct_answer": "A", "explanation": "Correct answer A reflects the primary adverse effect where dislocations accumulate during cold working, increasing strength but reducing ductility. Option B exploits the common misconception that work hardening affects intrinsic properties like conductivity, which actually remains largely unchanged. Option C uses a plausible-sounding but incorrect thermal effect, as work hardening doesn't inherently cause anisotropic expansion. Option D traps those who confuse work hardening with solid solution strengthening mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1200, "question": "When a copper single crystal is stretched, if the force axis is in the [001] direction and the critical resolved shear stress is 0.64 MPa, what tensile stress is required to initiate slip in the crystal?", "answer": "Since copper is face-centered cubic, the slip plane is {111} and the slip direction is <110>. Given that the force axis is [001], the four slip directions [110] and [1-10] are excluded, leaving eight equivalent slip systems. γ = 45°. cosλ = cos45° = √2/2. cosφ = |1×0 + 1×0 + 1×0| / (√(1² + 1² + 1²) × √(0² + 0² + 1²)) = √3/3. The formula is σ = τ / Ω = 0.64 / (cosλ cosφ) = 1.57 MPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解所需的拉伸应力，解答过程中涉及到了临界分切应力、滑移面和滑移方向的计算，最终得出具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括确定滑移系统、计算取向因子（cosλ和cosφ），并应用临界分切应力公式。虽然涉及的概念和公式是基础的，但需要综合运用多个知识点并进行适当的数值计算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、滑移系统和临界分切应力等概念，并进行多步骤计算和综合分析。虽然题目提供了部分关键信息，但解题过程涉及多个计算步骤和概念关联，对学生的知识掌握和计算能力要求较高。", "convertible": true, "correct_option": "1.57 MPa", "choice_question": "When a copper single crystal is stretched with the force axis in the [001] direction and a critical resolved shear stress of 0.64 MPa, what tensile stress is required to initiate slip in the crystal?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.57 MPa", "B": "0.64 MPa", "C": "1.11 MPa", "D": "2.22 MPa" }, "correct_answer": "A", "explanation": "The correct answer is A (1.57 MPa) because it properly applies the Schmid factor calculation for slip in the [001] direction. Option B (0.64 MPa) is the critical resolved shear stress itself, exploiting the common mistake of confusing applied stress with resolved shear stress. Option C (1.11 MPa) is derived from an incorrect slip plane assumption, targeting those who misapply the {111} plane geometry. Option D (2.22 MPa) doubles the correct answer, preying on the tendency to overcompensate when considering multiple slip systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2238, "question": "Determine whether the following statement is correct. (11) Recrystallization texture is the deformation texture retained during the recrystallization process.", "answer": "Incorrect. Recrystallization texture is the texture formed during the recrystallization (primary, secondary) process of cold-deformed metals. It is formed on the basis of deformation texture, with two scenarios: one is retaining the original deformation texture, and the other is the disappearance of the original deformation texture, replaced by a new recrystallization texture.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目明确要求判断陈述的正确性（Determine whether the following statement is correct），且答案直接给出了该陈述是错误的（Incorrect）并解释了原因，符合判断题的特征。 | 知识层次: 题目考查对再结晶织构这一基本概念的记忆和理解，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度等级。题目要求判断关于再结晶织构的陈述是否正确，需要考生理解再结晶织构的定义及其与变形织构的关系。虽然涉及基础概念记忆，但需要一定的概念理解和应用能力，属于中等偏下的难度。", "convertible": true, "correct_option": "Incorrect. Recrystallization texture is the texture formed during the recrystallization (primary, secondary) process of cold-deformed metals. It is formed on the basis of deformation texture, with two scenarios: one is retaining the original deformation texture, and the other is the disappearance of the original deformation texture, replaced by a new recrystallization texture.", "choice_question": "Determine whether the following statement is correct. (11) Recrystallization texture is the deformation texture retained during the recrystallization process.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All recrystallization textures in cold-deformed metals completely replace the original deformation texture.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is incorrect because recrystallization textures can either retain the original deformation texture or replace it with a new texture. The use of 'all' makes this an absolute statement that doesn't account for the variability observed in actual material behavior. This is a combination of precision trap (using 'all') and concept boundary issue (ignoring the dual possibilities in recrystallization textures).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1331, "question": "Explain the origin and morphological characteristics of Fe3C eutectic", "answer": "Fe3C eutectic: The cementite in the eutectic product ledeburite, which generally exists as the matrix.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释Fe3C共晶的起源和形态特征，需要文字解释和论述，答案也以文字形式给出，符合简答题的特征。 | 知识层次: 题目考查对Fe3C eutectic的基本概念和形态特征的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释Fe3C共晶的起源和形态特征，但正确选项已经提供了关键信息（Fe3C共晶是莱氏体中的渗碳体，通常作为基体存在）。这需要考生具备基础概念记忆能力，能够识别和描述材料科学中的基本相组成和形态特征，但不需要进行复杂的分析或多概念整合。", "convertible": true, "correct_option": "The cementite in the eutectic product ledeburite, which generally exists as the matrix.", "choice_question": "Which of the following best describes the origin and morphological characteristics of Fe3C eutectic?", "conversion_reason": "The answer is a standard description of Fe3C eutectic, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The cementite in the eutectic product ledeburite, which generally exists as the matrix.", "B": "Fe3C forms as discrete particles uniformly distributed in the ferrite phase during eutectic reaction.", "C": "The eutectic Fe3C primarily nucleates at grain boundaries and grows as dendritic structures.", "D": "Fe3C in eutectic structures appears as continuous thin films separating austenite phases." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes ledeburite's characteristic where cementite forms the matrix. Option B incorrectly suggests uniform particle distribution, exploiting the common misconception about precipitate morphology. Option C uses dendritic growth terminology that applies to primary solidification, not eutectic structures. Option D describes a pearlite-like morphology, creating confusion between eutectoid and eutectic structures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2818, "question": "There is an aluminum wire with a length of 5 m and a diameter of 3 mm. Given that the elastic modulus of aluminum is 70 GPa, find the total length of the wire under a tensile force of 200 N.", "answer": "Within the elastic range, stress and strain obey Hooke's law ${\\pmb\\sigma}{=}{\\pmb E}{\\pmb\\varepsilon}$, and $\\mathsf{e}=\\frac{\\boldsymbol{\\ell}-\\boldsymbol{l}_{0}}{\\boldsymbol{l}_{0}}{=}\\frac{\\frac{\\boldsymbol{F}}{A}}{E}$. Therefore, $$l=l_{0}+\\frac{F}{E A}l_{\\circ}=l_{0}\\left(1+\\frac{F}{E A}\\right)=5\\left[1+\\frac{200}{70\\times10^{3}\\times\\frac{\\pi}{4}(3\\times10^{-3})^{2}}\\right]$$$$=5.00202(\\mathrm{m})=5002.02(\\mathrm{mm})$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铝线在拉伸力作用下的总长度，答案中包含了具体的计算步骤和最终数值结果，符合计算题的特征。 | 知识层次: 题目主要考查Hooke's law的基本公式应用和简单计算，涉及弹性模量、应力和应变的基本概念，计算过程直接套用公式，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然题目涉及弹性模量、应力应变关系等概念，但解题过程仅需直接套用Hooke's定律公式，进行简单的代数运算即可得出结果。不需要复杂的推导或多步骤计算，属于选择题中较为基础的题型。", "convertible": true, "correct_option": "5002.02 mm", "choice_question": "An aluminum wire with a length of 5 m and a diameter of 3 mm is subjected to a tensile force of 200 N. Given that the elastic modulus of aluminum is 70 GPa, what is the total length of the wire under this force?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion to a multiple-choice format. The correct option can be derived from the provided solution.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5002.02 mm", "B": "5001.43 mm", "C": "5000.00 mm", "D": "5002.47 mm" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the formula for elastic deformation: ΔL = (F*L)/(A*E), where A is the cross-sectional area. Option B results from incorrectly using shear modulus instead of elastic modulus. Option C is a trap for those who neglect elastic deformation entirely. Option D comes from miscalculating the cross-sectional area by using radius instead of diameter.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4698, "question": "Under conditions where cupric oxide (CuO) is exposed to reducing atmospheres at elevated temperatures, some of the Cu2+ ions will become Cu+. How many Cu+ ions are required for the creation of each defect?", "answer": "There will be two Cu+ ions required for each of these defects.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释在特定条件下Cu2+离子转变为Cu+离子的缺陷形成机制，并具体说明每个缺陷需要多少个Cu+离子。答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要理解CuO在还原气氛下的缺陷形成机制，并分析Cu2+还原为Cu+的电荷平衡关系。这涉及多步概念关联和综合分析，但不需要复杂的机理解释或创新应用。 | 难度: 在选择题中属于较高难度，需要理解氧化铜在还原气氛下的缺陷形成机制，并能够进行多步计算和概念关联。题目不仅考察了学生对Cu2+和Cu+离子转换的理解，还要求综合分析缺陷形成的化学计量关系，这超出了基础记忆和简单应用的层次。", "convertible": true, "correct_option": "There will be two Cu+ ions required for each of these defects.", "choice_question": "Under conditions where cupric oxide (CuO) is exposed to reducing atmospheres at elevated temperatures, some of the Cu2+ ions will become Cu+. How many Cu+ ions are required for the creation of each defect?", "conversion_reason": "The answer is a specific and factual statement that can be directly used as a correct option in a multiple-choice question. The question can be presented as is, with the answer being one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Two Cu+ ions per defect", "B": "One Cu+ ion per defect", "C": "Three Cu+ ions per defect", "D": "One Cu+ and one oxygen vacancy per defect" }, "correct_answer": "A", "explanation": "The correct answer is A because charge neutrality requires two Cu+ ions to compensate for the loss of one Cu2+ ion. Option B exploits the cognitive bias of assuming a simple 1:1 substitution. Option C introduces an exaggerated value that might seem plausible in other defect chemistry contexts. Option D creates a multi-parameter trap by combining a partially correct concept (oxygen vacancy) with the wrong stoichiometry.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1590, "question": "In the heterogeneous nucleation model, when the contact angle θ between the nucleus and the substrate plane is π/2, what fraction of the homogeneous nucleation energy is the nucleation energy?", "answer": "Half", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释在特定条件下（接触角θ=π/2）异质形核能与均质形核能的比例关系，并给出了具体的答案（Half），这需要理解形核理论并应用相关概念进行解释，属于需要文字解释的简答题类型。 | 知识层次: 题目涉及异质成核模型中的接触角概念，需要理解接触角与成核能之间的关系，并进行简单的数学推导（当θ=π/2时，成核能是均质成核能的一半）。这属于中等应用层次，需要将概念与计算相结合，但不需要复杂的综合分析或推理。 | 难度: 在选择题中属于中等难度，需要理解异质成核模型中的接触角概念，并能将其与均质成核能量进行关联计算。虽然题目给出了具体角度（π/2），但仍需掌握能量分数计算的基本原理，属于需要多步概念关联和综合分析的中等应用层次。", "convertible": true, "correct_option": "Half", "choice_question": "In the heterogeneous nucleation model, when the contact angle θ between the nucleus and the substrate plane is π/2, what fraction of the homogeneous nucleation energy is the nucleation energy?", "conversion_reason": "The answer is a standard term (Half) and the question can be converted into a multiple-choice format by providing options including the correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1/2", "B": "1/√2", "C": "π/4", "D": "cos(π/4)" }, "correct_answer": "A", "explanation": "The correct answer is A (1/2) because when θ=π/2, the shape factor f(θ) in the heterogeneous nucleation energy equation becomes 1/2. Option B (1/√2) exploits the common confusion with trigonometric identities. Option C (π/4) leverages the numerical similarity to the angle value. Option D (cos(π/4)) creates a trap by introducing a mathematically valid but physically irrelevant trigonometric function.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1181, "question": "The relationship between the direction of the dislocation line of an edge dislocation and the Burgers vector is (24)", "answer": "(24) perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答刃位错的位错线方向与伯格斯矢量之间的关系，答案需要简洁的文字描述（\"perpendicular\"），属于简答题类型。 | 知识层次: 题目考查刃型位错的位错线与伯格斯矢量方向关系的基本概念记忆，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即刃位错的位错线方向与伯格斯矢量之间的关系。题目直接给出正确选项\"perpendicular\"，无需复杂推理或概念比较，属于最基本的知识点回忆型题目。", "convertible": true, "correct_option": "perpendicular", "choice_question": "The relationship between the direction of the dislocation line of an edge dislocation and the Burgers vector is:", "conversion_reason": "The answer is a standard term (perpendicular), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "perpendicular", "B": "parallel", "C": "at 45 degrees", "D": "anti-parallel" }, "correct_answer": "A", "explanation": "The correct answer is A because for an edge dislocation, the Burgers vector is perpendicular to the dislocation line by definition. Option B is a cognitive bias trap, as it mimics the relationship in screw dislocations. Option C exploits the common 45-degree slip systems in FCC metals. Option D creates confusion by suggesting an inverse relationship that doesn't exist in dislocation theory.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4664, "question": "Beryllium (Be) has an HCP unit cell for which the ratio of the lattice parameters c/a is 1.568. If the radius of the Be atom is 0.1143nm, calculate the theoretical density of Be and compare it with the literature value.", "answer": "the theoretical density of be is 1.84 g/cm3, and the literature value is 1.85 g/cm3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（HCP晶胞参数、原子半径与密度的关系）来求解铍的理论密度，并将计算结果与文献值进行比较。答案呈现为具体数值计算结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算（包括晶格参数计算、体积计算、密度计算等），并涉及HCP晶体结构的基本概念和公式应用，需要将多个知识点关联起来进行综合分析。虽然不涉及复杂的推理或创新设计，但思维过程比简单应用更为深入。 | 难度: 在选择题中属于中等偏上难度，需要理解HCP晶体结构参数关系、原子半径与晶格参数转换、理论密度计算公式等多个概念，并进行多步骤计算和文献值对比分析。虽然选择题提供了正确选项降低了部分难度，但仍需掌握晶体学知识和单位换算能力才能正确解答。", "convertible": true, "correct_option": "1.84 g/cm3", "choice_question": "Beryllium (Be) has an HCP unit cell for which the ratio of the lattice parameters c/a is 1.568. If the radius of the Be atom is 0.1143nm, what is the theoretical density of Be?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.84 g/cm³", "B": "2.36 g/cm³", "C": "1.65 g/cm³", "D": "1.92 g/cm³" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算HCP晶胞体积和原子数得到的理论密度。干扰项B错误地使用了FCC堆积因子计算，利用了认知偏差。干扰项C故意忽略了c/a比值的精确影响，制造专业直觉陷阱。干扰项D在计算时错误地使用了原子直径而非半径，属于多层次验证陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1227, "question": "What is the essential difference between recrystallization and secondary recrystallization?", "answer": "Recrystallization refers to the process in which a cold-worked metal is heated to a certain temperature, and new distortion-free equiaxed grains are regenerated within the deformed structure, restoring the properties to the softened state before cold working. Secondary recrystallization refers to the phenomenon where, after recrystallization annealing, the metal is held at a higher temperature or for a longer time, causing a very few grains to rapidly consume other grains and grow, resulting in the entire metal being composed of a few exceptionally large grains that are tens to hundreds of times larger than those after recrystallization. The essential difference between the two: Recrystallization is a process of nucleation and growth, while secondary recrystallization is only a growth process. The driving force for recrystallization is stored energy, whereas for secondary recrystallization, it is interfacial energy. After recrystallization, strength and hardness decrease while plasticity and toughness increase, whereas after secondary recrystallization, the material's strength, plasticity, and toughness all decrease.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述recrystallization和secondary recrystallization之间的本质区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释和论述再结晶和二次再结晶的本质区别，涉及多个概念的理解和关联，包括过程描述、驱动力分析以及性能变化等。虽然不涉及复杂的计算或深度推理，但需要对相关概念进行综合分析和比较，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅要理解再结晶和二次再结晶的基本概念，还需要掌握两者在本质上的区别，包括过程、驱动力以及材料性能的变化。这需要考生具备较强的概念关联能力和综合分析能力，能够从多个角度进行比较和论述。此外，题目中的正确选项包含了多个关键点，考生需要准确理解并区分这些细节，这增加了题目的复杂性和难度。因此，该题目在选择题型内属于等级4的难度。", "convertible": true, "correct_option": "Recrystallization is a process of nucleation and growth, while secondary recrystallization is only a growth process. The driving force for recrystallization is stored energy, whereas for secondary recrystallization, it is interfacial energy. After recrystallization, strength and hardness decrease while plasticity and toughness increase, whereas after secondary recrystallization, the material's strength, plasticity, and toughness all decrease.", "choice_question": "What is the essential difference between recrystallization and secondary recrystallization?", "conversion_reason": "The answer is a standard explanation of the differences between the two processes, which can be presented as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization involves both nucleation and growth, while secondary recrystallization is primarily grain boundary migration driven by surface energy minimization", "B": "Both processes are identical, but secondary recrystallization occurs at higher temperatures due to additional stored energy from prior deformation", "C": "Recrystallization reduces dislocation density, while secondary recrystallization increases it through abnormal grain growth mechanisms", "D": "The key difference lies in the crystallographic texture: recrystallization randomizes texture while secondary recrystallization enhances it" }, "correct_answer": "A", "explanation": "The correct answer A precisely captures the fundamental mechanisms: nucleation+growth vs. pure growth, and correctly identifies the different driving forces (stored energy vs. interfacial energy). Option B exploits the common misconception that temperature alone differentiates the processes. Option C reverses the dislocation density relationship, playing on intuitive but incorrect assumptions about grain growth. Option D describes a potential outcome rather than the essential difference, targeting AI's tendency to focus on observable results over underlying mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3463, "question": "Discuss the microstructural characteristics and processing techniques of ZGMn13", "answer": "ZGMn13 is a wear-resistant steel with an austenitic microstructure at room temperature. Whether in the as-cast, forged, or hot-rolled condition, carbides precipitate along the austenite grain boundaries, reducing the steel's toughness and wear resistance. Therefore, water toughening treatment must be performed. After water toughening, it exhibits good toughness. During subsequent use, under strong compressive stress, martensitic transformation occurs, thereby increasing its wear resistance. Hence, this type of steel is used in applications subject to strong compressive stress.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求讨论ZGMn13的微观结构特征和加工技术，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求讨论ZGMn13的显微组织特征和加工技术，涉及多个概念（如奥氏体组织、碳化物析出、水韧处理、马氏体转变等）的关联和综合分析。虽然不需要复杂的推理或创新设计，但需要理解不同加工条件对材料性能的影响，并进行多步分析。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求考生掌握ZGMn13钢的基本微观结构特征（如奥氏体组织和碳化物析出），还需要理解不同加工状态（铸态、锻造、热轧）对材料性能的影响。此外，题目还涉及水韧处理的作用机制和后续使用中的马氏体相变过程，这要求考生能够将多个概念（如相变、加工工艺、力学性能）进行关联和综合分析。虽然题目提供了正确选项，但理解和分析这些复杂的概念和过程在选择题型中仍属于多角度分析论述的难度等级。", "convertible": true, "correct_option": "ZGMn13 is a wear-resistant steel with an austenitic microstructure at room temperature. Whether in the as-cast, forged, or hot-rolled condition, carbides precipitate along the austenite grain boundaries, reducing the steel's toughness and wear resistance. Therefore, water toughening treatment must be performed. After water toughening, it exhibits good toughness. During subsequent use, under strong compressive stress, martensitic transformation occurs, thereby increasing its wear resistance. Hence, this type of steel is used in applications subject to strong compressive stress.", "choice_question": "Which of the following best describes the microstructural characteristics and processing techniques of ZGMn13?", "conversion_reason": "The answer is a detailed and standard description of the microstructural characteristics and processing techniques of ZGMn13, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ZGMn13 is a wear-resistant steel with an austenitic microstructure at room temperature. Whether in the as-cast, forged, or hot-rolled condition, carbides precipitate along the austenite grain boundaries, reducing the steel's toughness and wear resistance. Therefore, water toughening treatment must be performed. After water toughening, it exhibits good toughness. During subsequent use, under strong compressive stress, martensitic transformation occurs, thereby increasing its wear resistance. Hence, this type of steel is used in applications subject to strong compressive stress.", "B": "ZGMn13 is a high-strength low-alloy steel with a predominantly martensitic microstructure. The key processing technique involves rapid quenching from austenitizing temperature to achieve maximum hardness. The steel maintains its hardness during service without requiring any phase transformation under stress.", "C": "ZGMn13 is an austenitic stainless steel that relies on chromium carbide precipitation for its wear resistance. The optimal processing route involves slow cooling to allow maximum carbide precipitation along grain boundaries. No additional heat treatment is required as the as-cast microstructure provides the best combination of properties.", "D": "ZGMn13 is a dual-phase steel with alternating layers of ferrite and martensite. The unique processing involves intercritical annealing followed by controlled cooling to achieve the layered microstructure. The wear resistance comes from the hardness difference between the two phases rather than any stress-induced transformation." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes ZGMn13's unique characteristics: austenitic matrix, carbide precipitation issues requiring water toughening, and stress-induced martensitic transformation during service. Option B incorrectly describes it as martensitic HSLA steel. Option C falsely presents it as austenitic stainless steel relying on chromium carbides. Option D wrongly characterizes it as a dual-phase steel with layered microstructure. These distractors exploit common material classification errors and processing technique misconceptions in steel metallurgy.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2935, "question": "The dislocation that cannot undergo climb motion is (A) Shockley partial dislocation (B) Frank partial dislocation (C) edge perfect dislocation", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项(A)、(B)、(C)中选择一个正确答案 | 知识层次: 题目考查对位错类型及其运动方式的基本概念记忆和理解，属于材料科学中晶体缺陷的基础知识范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解不同类型位错（Shockley partial dislocation、Frank partial dislocation、edge perfect dislocation）的基本特性，并能够区分它们之间的运动方式。特别是需要知道Shockley partial dislocation不能进行climb motion这一特定知识点。这比单纯记忆定义要复杂一些，但不需要进行深度分析或多概念比较。", "convertible": true, "correct_option": "A", "choice_question": "The dislocation that cannot undergo climb motion is", "conversion_reason": "原题目已经是单选题格式，可以直接转换。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Shockley partial dislocation", "B": "Frank partial dislocation", "C": "edge perfect dislocation", "D": "screw perfect dislocation" }, "correct_answer": "A", "explanation": "Shockley partial dislocations cannot undergo climb because they have a mixed character (partial edge and screw components) and their Burgers vector lies in the slip plane. Frank partial dislocations (B) can climb as they are pure edge type. Both perfect edge (C) and screw (D) dislocations can climb, though screw dislocations require non-conservative motion. The difficulty lies in recognizing that partial dislocations' behavior differs based on their Burgers vector orientation, not just their edge/screw character.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4566, "question": "Briefly describe the sacrificial anode technique used for galvanic protection.", "answer": "A sacrificial anode is electrically coupled to the metal piece to be protected, which anode is also situated in the corrosion environment. The sacrificial anode is a metal or alloy that is chemically more reactive in the particular environment. It (the anode) preferentially oxidizes, and, upon giving up electrons to the other metal, protects it from electrochemical corrosion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述牺牲阳极技术用于电化学保护的原理，答案以文字解释和论述的形式呈现，符合简答题的特征。 | 知识层次: 题目考查对牺牲阳极技术的基本概念和原理的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但要求考生不仅要记住牺牲阳极的定义，还需要理解其工作原理和应用场景。正确选项中对牺牲阳极的描述较为详细，包括其电耦合方式、化学活性优先氧化等关键点，这比简单的定义记忆要求更高，属于概念解释和描述的层次。", "convertible": true, "correct_option": "A sacrificial anode is electrically coupled to the metal piece to be protected, which anode is also situated in the corrosion environment. The sacrificial anode is a metal or alloy that is chemically more reactive in the particular environment. It (the anode) preferentially oxidizes, and, upon giving up electrons to the other metal, protects it from electrochemical corrosion.", "choice_question": "Which of the following best describes the sacrificial anode technique used for galvanic protection?", "conversion_reason": "The answer is a standard description of the sacrificial anode technique, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A sacrificial anode is electrically coupled to the metal piece to be protected, which anode is also situated in the corrosion environment. The sacrificial anode is a metal or alloy that is chemically more reactive in the particular environment. It (the anode) preferentially oxidizes, and, upon giving up electrons to the other metal, protects it from electrochemical corrosion.", "B": "A sacrificial anode works by creating a physical barrier between the protected metal and the corrosive environment. The anode material is chosen for its ability to form stable oxides that shield the underlying metal.", "C": "The technique involves applying an external voltage to make the protected metal act as the anode, thereby preventing its oxidation. The 'sacrificial' aspect refers to the energy cost of maintaining this voltage.", "D": "Sacrificial anodes function by altering the pH of the local environment to make it less corrosive. The anode material dissolves to release ions that buffer the solution chemistry." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the electrochemical mechanism where the more reactive anode corrodes preferentially. Option B incorrectly describes a barrier protection mechanism, exploiting confusion between galvanic and barrier protection. Option C reverses the anode/cathode roles and misrepresents the sacrificial concept, playing on voltage application misconceptions. Option D introduces a plausible but incorrect solution chemistry mechanism, targeting knowledge gaps in environmental modification methods.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4171, "question": "(b) Cite two important additional refinements that resulted from the wave-mechanical atomic model.", "answer": "Two important refinements resulting from the wave-mechanical atomic model are (1) that electron position is described in terms of a probability distribution, and (2) electron energy is quantized into both shells and subshells--each electron is characterized by four quantum numbers.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举两个重要的改进，并需要简要解释每个改进的内容，这符合简答题的特征，即需要文字解释和论述。 | 知识层次: 题目考查对波动力学原子模型带来的两个重要改进的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列举两个重要的改进点，但这两个点都是基于波动力学原子模型的基础概念记忆。正确选项直接给出了明确的定义和分类（概率分布和量子化能级），不需要复杂的分析或比较。然而，考生需要准确记忆并理解这两个关键概念，这比单纯记忆基本定义（等级1）要求稍高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "Electron position is described in terms of a probability distribution, and electron energy is quantized into both shells and subshells--each electron is characterized by four quantum numbers.", "choice_question": "Which of the following are two important refinements resulting from the wave-mechanical atomic model?", "conversion_reason": "The answer provides specific and standard refinements that can be converted into a multiple-choice format by listing these refinements as options and asking the question in a 'which of the following' format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Electron position is described in terms of a probability distribution, and electron energy is quantized into both shells and subshells", "B": "Electrons move in fixed circular orbits, and their energy levels are continuous", "C": "Electron position can be precisely determined, and their energy is quantized into shells only", "D": "Electrons exhibit both particle and wave nature, but their positions are fixed in space" }, "correct_answer": "A", "explanation": "The correct answer A captures the two key refinements: probabilistic electron location and multi-level quantization. Option B combines Bohr model errors with classical mechanics. Option C contradicts the uncertainty principle while oversimplifying quantization. Option D correctly identifies wave-particle duality but incorrectly fixes electron positions, exploiting confusion between classical and quantum concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1224, "question": "Stacking faults result from the local presence of an extra half atomic plane in the crystal lattice.", "answer": "~\\\\times~", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（对错），答案形式为判断符号（~\\\\times~表示错误），符合判断题的特征 | 知识层次: 题目考查堆垛层错的基本概念，属于晶体缺陷的基础知识，主要依赖记忆和理解。 | 难度: 该题目属于基础概念记忆层次，仅需判断关于堆垛缺陷的定义是否正确。在选择题型中，这类题目仅涉及单一概念的正误判断，无需深入理解或分析，因此属于最低难度等级。", "convertible": true, "correct_option": "~\\\\times~", "choice_question": "Stacking faults result from the local presence of an extra half atomic plane in the crystal lattice.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, some oxide ceramics like partially stabilized zirconia can exhibit transformation toughening and pseudo-ductile behavior. The absolute term 'all' makes this statement false. This tests understanding of exceptions in material behavior and the danger of absolute statements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4715, "question": "Calculate the number of atoms per cubic meter in chromium.", "answer": "the number of atoms per cubic meter in chromium is 8.33 × 10^{28} \\ \\text{atoms/m}^3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算铬中每立方米的原子数），答案是一个具体的数值结果（8.33 × 10^{28} atoms/m^3），这符合计算题的特征。 | 知识层次: 题目要求计算铬中每立方米的原子数，这需要应用基本的密度和摩尔质量公式进行简单计算，属于直接套用基本公式的应用层次，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目仅要求计算铬的原子密度，可以直接套用已知的铬的原子密度公式或数据（8.33 × 10^{28} atoms/m^3），无需进行复杂的推导或多步骤计算。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "8.33 × 10^{28} atoms/m^3", "choice_question": "What is the number of atoms per cubic meter in chromium?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.33 × 10^{28} atoms/m^3", "B": "6.02 × 10^{28} atoms/m^3", "C": "1.18 × 10^{29} atoms/m^3", "D": "7.19 × 10^{28} atoms/m^3" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using chromium's density (7.19 g/cm³), atomic weight (52 g/mol), and Avogadro's number. Option B mimics the approximate value of Avogadro's number (6.02 × 10^{23}) scaled incorrectly. Option C represents a common error of using the inverse of the correct packing factor. Option D uses the correct density value but fails to complete the full calculation, exploiting partial calculation bias.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3077, "question": "In fiber-reinforced composites, the fibers with relatively good performance are mainly (1), (2), (3), (4).", "answer": "(1)glass fiber; (2)carbon fiber; (3)boron fiber; (4)silicon carbide fiber", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举性能较好的纤维增强复合材料中的纤维类型，答案以列举的形式给出，不需要计算或判断对错，属于简答题类型。 | 知识层次: 题目主要考查对纤维增强复合材料中常用高性能纤维种类的记忆，属于基础概念和分类知识的范畴，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆纤维增强复合材料中性能较好的纤维类型，属于基础概念记忆的简单题目。题目提供了明确的选项，无需进行复杂的概念解释或比较分析，仅需识别和回忆相关知识即可。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "glass fiber; carbon fiber; boron fiber; silicon carbide fiber", "choice_question": "In fiber-reinforced composites, which of the following fibers have relatively good performance?", "conversion_reason": "The original question asks for fibers with good performance in fiber-reinforced composites, and the answer provides a list of standard terms. This can be converted into a multiple-choice question by listing the options and selecting the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Carbon fiber (high modulus grade)", "B": "Polyethylene fiber (ultra-high molecular weight)", "C": "Steel fiber (austenitic stainless grade)", "D": "Alumina fiber (polycrystalline)" }, "correct_answer": "A", "explanation": "The correct answer is A because high modulus carbon fibers exhibit exceptional specific stiffness and strength, making them ideal for high-performance composites. Option B exploits cognitive bias by presenting UHMWPE fibers which have high tensile strength but poor compressive performance and thermal stability. Option C is a professional intuition trap using steel fibers which have good bulk properties but excessive density for most composite applications. Option D is a multi-level verification trap with polycrystalline alumina fibers that appear attractive but suffer from grain boundary weaknesses compared to single crystal reinforcements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2070, "question": "Point out the errors in the following concept and correct them: (11) In order to produce a batch of sand castings with significant thickness variations and require uniform grain size, it can be satisfied by merely adding nucleating agents in the process.", "answer": "It can be satisfied by merely accelerating the cooling of thicker sections (such as adding chills) in the process.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。答案也以文字形式给出，解释了如何通过加速较厚部分的冷却来满足要求。 | 知识层次: 题目要求识别并纠正关于铸造过程中晶粒尺寸控制的错误概念，需要理解晶粒尺寸控制的基本原理（如冷却速率的影响）以及如何在实际操作中应用这些原理（如使用冷却装置）。这涉及到多步思考和概念关联，但不需要复杂的综合分析或创新设计。 | 难度: 在选择题中属于中等难度，需要理解砂型铸造中晶粒尺寸均匀性的控制原理，并综合分析冷却速度与成核剂的作用机制。题目要求识别原概念的误区（仅靠成核剂无法解决厚度差异问题），并选择正确的工艺措施（加速厚壁部分冷却）。这涉及中等应用层次的知识关联和工艺综合分析能力，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "It can be satisfied by merely accelerating the cooling of thicker sections (such as adding chills) in the process.", "choice_question": "Point out the correct way to produce a batch of sand castings with significant thickness variations and require uniform grain size:", "conversion_reason": "The original short answer question can be converted into a multiple-choice question by providing the correct answer as one of the options and possibly adding plausible distractors. The answer is a specific statement that can serve as the correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Using directional solidification with controlled heat extraction rates", "B": "Adding grain refiners to the entire melt before pouring", "C": "Maintaining constant cooling rate throughout all sections", "D": "Applying ultrasonic vibration during solidification" }, "correct_answer": "A", "explanation": "Correct answer (A) addresses thickness variations by controlling heat extraction directionally. Option B is a cognitive bias trap - refiners help nucleation but don't solve thickness-related grain size variations. Option C is a professional intuition trap - constant cooling rate would cause non-uniform grains in varying thicknesses. Option D is a multi-level verification trap - while ultrasound affects grain size, it doesn't specifically address thickness variation challenges.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3935, "question": "Which of these elements would you expect to form a substitutional solid solution having complete solubility with copper? The elements are: Ni, O, H, Pt, Pd, Co, C, Zn, Ag, Al, Cr, Fe. The criteria for complete solubility are: 1) the difference in atomic radii between Cu and the other element must be less than ±15%, 2) the crystal structures must be the same, 3) the electronegativities must be similar, and 4) the valences should be the same, or nearly the same.", "answer": "Ni, Pd, and Pt meet all of the criteria and thus form substitutional solid solutions having complete solubility. At elevated temperatures Co and Fe experience allotropic transformations to the FCC crystal structure, and thus display complete solid solubility at these temperatures.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求根据给定的标准（原子半径差异、晶体结构、电负性和价态）分析多个元素，并解释哪些元素满足所有条件形成完全固溶体。答案需要详细的文字解释和论述，而非简单的选择或判断。 | 知识层次: 题目要求应用多个标准（原子半径差异、晶体结构、电负性、价态）来筛选元素，涉及多步分析和概念关联。虽然不涉及复杂计算，但需要对材料科学中的固溶体形成条件有较深入的理解和综合应用能力。 | 难度: 在选择题中属于较高难度，需要综合考虑多个因素（原子半径差异、晶体结构、电负性、价态）并进行多步分析。题目要求考生不仅掌握基本概念，还需要能够将这些概念关联起来，对不同元素进行系统性比较。此外，题目还涉及高温条件下的同素异形转变（Co和Fe），增加了分析的复杂性。虽然题目提供了明确的选择范围，但正确选项的确定需要深入理解和综合应用材料科学原理。", "convertible": true, "correct_option": "Ni, Pd, and Pt", "choice_question": "Which of these elements would you expect to form a substitutional solid solution having complete solubility with copper, considering the criteria of atomic radii difference less than ±15%, same crystal structure, similar electronegativities, and same or nearly the same valences?", "conversion_reason": "The answer is a specific set of elements that meet the given criteria, making it suitable for conversion into a multiple-choice question where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ni, Pd, Pt", "B": "Ag, Al, Zn", "C": "Co, Fe, Cr", "D": "O, H, C" }, "correct_answer": "A", "explanation": "The correct answer is A (Ni, Pd, Pt) because these elements meet all the criteria for complete solubility with copper: they have FCC crystal structure (same as Cu), atomic radii differences within ±15% (Ni: 124pm, Pd: 137pm, Pt: 139pm vs Cu: 128pm), similar electronegativities, and same valence. Option B (Ag, Al, Zn) is a cognitive bias trap - while Ag has FCC structure and similar radius, Al and Zn have different structures. Option C (Co, Fe, Cr) exploits professional intuition - these are common alloying elements but have different crystal structures. Option D (O, H, C) is an extreme case to test if the model recognizes these would form interstitial solutions, not substitutional.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 592, "question": "Explain the term: grain boundary segregation", "answer": "Grain boundary segregation: The enrichment phenomenon of solute atoms or impurity atoms at grain boundaries due to the difference in distortion energy between the grain interior and the grain boundaries or the presence of vacancies.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释术语\"grain boundary segregation\"，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对晶界偏析这一基础概念的定义和基本原理的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释\"grain boundary segregation\"这一概念，但正确选项已经提供了较为完整的定义和基本原理说明。学生需要理解并记忆晶界偏析的定义、成因（晶内与晶界畸变能差异或空位存在）以及表现形式（溶质原子或杂质原子在晶界的富集现象），这超出了简单定义记忆的要求，但尚未达到需要阐述复杂概念体系的难度。", "convertible": true, "correct_option": "The enrichment phenomenon of solute atoms or impurity atoms at grain boundaries due to the difference in distortion energy between the grain interior and the grain boundaries or the presence of vacancies.", "choice_question": "Which of the following best describes grain boundary segregation?", "conversion_reason": "The answer is a standard definition of the term 'grain boundary segregation', which can be converted into a multiple-choice question format by presenting it as the correct option among other plausible but incorrect definitions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The enrichment phenomenon of solute atoms or impurity atoms at grain boundaries due to the difference in distortion energy between the grain interior and the grain boundaries or the presence of vacancies", "B": "The diffusion of solute atoms from grain boundaries into the grain interior driven by chemical potential gradients", "C": "The formation of secondary phases at grain boundaries due to local composition exceeding solubility limits", "D": "The preferential oxidation of grain boundaries in polycrystalline materials due to higher defect density" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely describes grain boundary segregation as the enrichment of solute/impurity atoms at boundaries due to energy differences or vacancies. Option B is incorrect because it describes reverse diffusion (from boundaries to interior), exploiting the common confusion between segregation and diffusion. Option C is a plausible but incorrect description of precipitation at grain boundaries, designed to trap those who confuse segregation with precipitation. Option D describes grain boundary oxidation, which is a related but distinct phenomenon, exploiting the tendency to associate all grain boundary phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1399, "question": "Determine whether the following statement is correct: Edge dislocations can undergo cross-slip.", "answer": "Incorrect", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断一个陈述的正确性（\"Edge dislocations can undergo cross-slip\"），并且给出了明确的判断结果（\"Incorrect\"）。这符合判断题的特征，即只需要判断陈述的对错，而不需要选择、计算或详细解释。 | 知识层次: 题目考查对位错基本行为（边缘位错的交滑移能力）这一基础概念的记忆和理解，属于材料科学中晶体缺陷的基础知识范畴。 | 难度: 该题目属于基础概念正误判断，仅需记忆边缘位错的基本特性即可作答。在选择题型中属于最简单的难度等级，不需要复杂分析或概念间的比较。", "convertible": true, "correct_option": "Incorrect", "choice_question": "Determine whether the following statement is correct: Edge dislocations can undergo cross-slip.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials exhibit a clear glass transition temperature when heated.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many amorphous materials do show a glass transition temperature, this is not universally true for all amorphous materials. Some may decompose before reaching Tg, or the transition may be too subtle to detect. The statement's use of 'all' creates an absolute claim that doesn't account for exceptions in material behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3910, "question": "Rhodium has an atomic radius of 0.1345nm, a density of (12.41g / {cm}^{3}) and an atomic weight of 102.91 \\mathrm{g} / mol. What is rhodium's crystal structure?(a) Simple cubic(b) \\mathrm{BCC}(c) \\mathrm{FCC}", "answer": "the crystal structure for rhodium is \\mathrm{fcc}.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从选项(a) Simple cubic、(b) BCC、(c) FCC中选择正确答案 | 知识层次: 题目需要根据给定的原子半径、密度和原子重量，通过多步计算和综合分析来确定晶体的结构。这涉及到对晶体结构类型的基本理解，以及如何将这些参数与理论值进行比较的能力。虽然不涉及复杂的推理或创新应用，但需要一定的计算和概念关联能力。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目要求考生掌握原子半径、密度、原子重量与晶体结构之间的关系。其次，解题过程涉及多步计算，包括计算单位晶胞中的原子数、晶胞体积等，并需要将这些计算结果与不同晶体结构（SC、BCC、FCC）的理论值进行比较。此外，题目还要求考生能够正确应用相关公式和概念，综合分析计算结果才能得出正确答案。因此，该题目在选择题型内属于复杂分析过程的判断，难度等级为4。", "convertible": true, "correct_option": "FCC", "choice_question": "Rhodium has an atomic radius of 0.1345nm, a density of (12.41g / {cm}^{3}) and an atomic weight of 102.91 \\mathrm{g} / mol. What is rhodium's crystal structure?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Simple cubic", "B": "BCC", "C": "FCC", "D": "HCP" }, "correct_answer": "C", "explanation": "正确答案是FCC，因为通过计算原子堆积因子(APF)可以验证。对于FCC结构，APF=0.74，与给定数据计算结果一致。干扰项A利用了对稀有金属常见结构的错误直觉，B利用了过渡金属常出现BCC结构的认知偏差，D则利用了密排结构的表面相似性但忽略了HCP的c/a比要求。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4178, "question": "Give the electron configuration for the ion Fe2+.", "answer": "The electron configuration for an Fe2+ ion is 1s2 2s2 2p6 3s2 3p6 3d6.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求给出Fe2+离子的电子排布，需要文字描述电子排布的具体情况，而不是从选项中选择、判断对错或进行数值计算。 | 知识层次: 题目考查对电子排布基本概念的记忆和理解，仅需根据原子序数和离子电荷数直接写出电子排布式，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求的是基础概念记忆（电子排布），但需要学生掌握铁原子的电子排布（1s2 2s2 2p6 3s2 3p6 4s2 3d6）并理解Fe2+离子是通过失去两个4s电子形成的。这涉及对电子填充顺序和离子形成过程的理解，而不仅仅是简单的定义记忆。因此，它比纯粹的定义记忆题（等级1）稍复杂，但不需要复杂的分析或比较（等级3）。", "convertible": true, "correct_option": "1s2 2s2 2p6 3s2 3p6 3d6", "choice_question": "What is the electron configuration for the ion Fe2+?", "conversion_reason": "The answer is a standard and specific electron configuration, which can be presented as a correct option among other plausible but incorrect configurations.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1s2 2s2 2p6 3s2 3p6 3d6", "B": "1s2 2s2 2p6 3s2 3p6 3d5 4s1", "C": "1s2 2s2 2p6 3s2 3p6 3d4 4s2", "D": "1s2 2s2 2p6 3s2 3p6 3d7" }, "correct_answer": "A", "explanation": "The correct answer is A because Fe2+ loses two electrons from the neutral Fe atom's 4s orbital first (1s2 2s2 2p6 3s2 3p6 3d6 4s2 → 1s2 2s2 2p6 3s2 3p6 3d6). Option B is a common mistake where AI might think the electron comes from the 3d orbital first. Option C represents an incorrect configuration where two electrons are removed from 3d instead of 4s. Option D is a trap where AI might forget to remove any electrons at all and just add one to 3d.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1747, "question": "In UO2 crystals, the diffusion of O2- proceeds via the mechanism. a. vacancy b. interstitial c. dopant point defect", "answer": "b", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的选项（a. vacancy b. interstitial c. dopant point defect）中选择一个正确答案（b），符合选择题的特征。 | 知识层次: 题目考查对UO2晶体中O2-扩散机制的基础概念记忆，属于对基本原理和分类的记忆性知识。 | 难度: 该题目属于基础概念记忆层次，要求考生了解UO2晶体中O2-的扩散机制。虽然需要记忆具体机制类型（间隙扩散），但不需要复杂的分析或比较过程。在选择题型中属于概念理解和简单辨析难度，比纯粹的概念识别（等级1）稍高，但低于需要深度理解的复杂概念区分（等级3）。", "convertible": true, "correct_option": "b. interstitial", "choice_question": "In UO2 crystals, the diffusion of O2- proceeds via the mechanism.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "vacancy", "B": "interstitial", "C": "dopant point defect", "D": "Frenkel defect" }, "correct_answer": "B", "explanation": "In UO2 crystals, oxygen diffusion primarily occurs through the interstitial mechanism due to the fluorite structure's inherent interstitial sites. The vacancy option (A) exploits the common misconception that anion diffusion typically occurs via vacancies. The dopant point defect (C) is a plausible-sounding but irrelevant mechanism in pure UO2. The Frenkel defect (D) is a high-difficulty distractor that references a real defect type but is not the dominant diffusion pathway in this material system.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3684, "question": "A 0.2-mm thick wafer of silicon is treated so that a uniform concentration gradient of antimony is produced. One surface contains 1 Sb atom per 10^8 Si atoms and the other surface contains 500 Sb atoms per 10^8 Si atoms. The lattice parameter for Si is 5.407 A. Calculate the concentration gradient in (a) atomic percent Sb per cm.", "answer": "-0.02495 at% sb/cm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算浓度梯度），并给出了具体的计算公式和步骤，最终需要得出一个具体的数值结果（-0.02495 at% sb/cm）。这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括浓度转换和梯度计算，涉及多个概念的综合应用，但不需要复杂的推理或深度分析。 | 难度: 在选择题中属于中等偏上难度，需要理解浓度梯度概念、原子百分比计算、单位转换等多个步骤的综合计算。虽然题目提供了关键参数，但解题过程涉及多个概念关联和单位换算，需要较强的综合分析能力。", "convertible": true, "correct_option": "-0.02495 at% sb/cm", "choice_question": "A 0.2-mm thick wafer of silicon is treated so that a uniform concentration gradient of antimony is produced. One surface contains 1 Sb atom per 10^8 Si atoms and the other surface contains 500 Sb atoms per 10^8 Si atoms. The lattice parameter for Si is 5.407 A. The concentration gradient in atomic percent Sb per cm is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-0.02495 at% Sb/cm", "B": "-0.0499 at% Sb/cm", "C": "-0.01247 at% Sb/cm", "D": "-0.00499 at% Sb/cm" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算浓度差除以厚度得到的。干扰项B通过错误地将浓度差直接除以厚度而不进行单位转换来迷惑；干扰项C通过错误地将厚度减半计算来迷惑；干扰项D通过错误地将浓度差除以厚度后再除以5来迷惑。这些干扰项利用了常见的计算错误和单位转换疏忽。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 786, "question": "5. Inverse spinel structure", "answer": "Inverse spinel structure: It belongs to the cubic crystal system, where oxygen ions can be considered as arranged in a cubic close packing. Divalent cation A fills the octahedral voids, while trivalent cation B fills half of the octahedral voids and half of the tetrahedral voids.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Inverse spinel structure\"进行文字解释和论述，答案提供了详细的晶体结构描述，属于需要文字解释的简答题类型。 | 知识层次: 题目考查对反尖晶石结构的基本定义和晶体学特征的记忆和理解，属于基础概念层次的知识点。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及反尖晶石结构的基本定义和离子填充方式，但需要考生理解和记忆多个关键点（如立方晶系、氧离子排列方式、二价和三价阳离子的填充位置等）。这些知识点属于基础概念记忆层次，但需要一定的描述和解释能力，而不仅仅是简单的定义复述。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "Inverse spinel structure: It belongs to the cubic crystal system, where oxygen ions can be considered as arranged in a cubic close packing. Divalent cation A fills the octahedral voids, while trivalent cation B fills half of the octahedral voids and half of the tetrahedral voids.", "choice_question": "下列关于反尖晶石结构的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Inverse spinel structure belongs to the cubic crystal system with oxygen ions in cubic close packing, where divalent cations occupy octahedral sites and trivalent cations are equally distributed between octahedral and tetrahedral sites", "B": "Inverse spinel structure is hexagonal with oxygen ions in hexagonal close packing, where all trivalent cations occupy tetrahedral sites and divalent cations occupy octahedral sites", "C": "Inverse spinel structure has tetragonal symmetry where divalent cations exclusively occupy tetrahedral voids while trivalent cations fill octahedral voids", "D": "Inverse spinel structure maintains cubic symmetry but with divalent cations in tetrahedral sites and trivalent cations randomly distributed in octahedral sites" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the inverse spinel structure's cubic symmetry, oxygen ion arrangement, and cation distribution. Option B incorrectly changes the crystal system to hexagonal and alters cation distribution. Option C falsely claims tetragonal symmetry and reverses the typical cation positions. Option D maintains cubic symmetry but incorrectly places divalent cations in tetrahedral sites, which is characteristic of normal spinel, not inverse spinel. These distractors exploit common misconceptions about crystal systems and cation site preferences in spinel structures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2072, "question": "Point out the errors in the following concept and correct them: (9) If 10,000 nucleation agents are added to an undercooled liquid, then 10,000 grains will form after crystallization.", "answer": "then tens of thousands of grains will form after crystallization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出概念中的错误并进行纠正，需要文字解释和论述，而不是简单的选择或判断。答案也是通过文字描述来修正错误概念。 | 知识层次: 题目要求识别并纠正关于成核剂与晶粒形成关系的错误概念，需要理解成核剂的作用机制和晶粒形成的多因素影响，涉及概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解成核剂的作用机制以及晶粒形成的原理，并进行综合分析。题目要求识别概念错误并给出正确表述，涉及多步计算和概念关联，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "then tens of thousands of grains will form after crystallization.", "choice_question": "Point out the errors in the following concept and select the correct option: (9) If 10,000 nucleation agents are added to an undercooled liquid, then 10,000 grains will form after crystallization.", "conversion_reason": "The original short answer question can be converted into a multiple-choice question because the answer is a specific correction to the given statement. The correct option is the provided answer, and the question can be rephrased to fit a multiple-choice format by asking to select the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The number of grains equals the number of nucleation agents because each agent initiates one grain", "B": "The number of grains will be less than 10,000 due to competitive growth and coalescence", "C": "The number of grains will be exactly 10,000 if the undercooling is precisely controlled", "D": "The number of grains will be orders of magnitude higher due to secondary nucleation effects" }, "correct_answer": "D", "explanation": "The correct answer is D because each nucleation agent can initiate multiple grains through secondary nucleation mechanisms, especially in undercooled liquids where thermal fluctuations promote additional nucleation events. Option A exploits the naive 1:1 assumption that AI models might make. Option B creates confusion by introducing valid but incomplete concepts (competitive growth). Option C uses precise numerical matching that seems scientifically plausible but ignores real-world nucleation dynamics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2103, "question": "Point out the errors in the following concept and correct them: Although the crystallization rate of solid solution alloys is very fast, at a certain moment during solidification, the chemical potentials of components A and B in the liquid and solid phases are equal.", "answer": "At the phase interface, the chemical potentials of components A and B in the liquid and solid phases are equal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求识别并纠正关于固溶体合金结晶速率和化学势的错误概念，涉及对相变过程中化学势平衡条件的理解和应用，需要将基础概念与实际相变过程关联起来进行分析和判断。 | 难度: 在选择题中属于中等难度，需要理解化学势平衡的概念，并能识别出题目中关于结晶速率与化学势平衡关系的错误表述。虽然不需要复杂的计算，但需要对相平衡和固溶体合金凝固过程有较深的理解，并能将多个概念关联起来进行分析。", "convertible": true, "correct_option": "At the phase interface, the chemical potentials of components A and B in the liquid and solid phases are equal.", "choice_question": "Which of the following correctly describes the condition during the solidification of solid solution alloys?", "conversion_reason": "The original short answer question asks for a specific correction to a concept, which can be rephrased into a multiple-choice format by presenting the correct statement as one of the options. The answer is a standard concept that can be directly used as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "At the phase interface, the chemical potentials of components A and B in the liquid and solid phases are equal", "B": "The solidification rate determines the equality of chemical potentials at the interface", "C": "Chemical potentials equalize only when the alloy reaches eutectic composition", "D": "The equality of chemical potentials is maintained throughout the entire solidification process" }, "correct_answer": "A", "explanation": "The correct answer A reflects the thermodynamic equilibrium condition at the phase interface during solidification. Option B exploits the common misconception that kinetics (solidification rate) affects thermodynamic equilibrium. Option C uses the specialized case of eutectic composition to create confusion. Option D extends the correct concept beyond its valid scope (interface only) to trap those who don't distinguish between local and global equilibrium.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4931, "question": "Visible light having a wavelength of 5 x 10^-7 m appears green. Compute the energy of a photon of this light.", "answer": "the energy of the photon is 3.98 x 10^-19 j (2.48 ev).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算光子的能量），并给出了具体的公式应用（使用波长计算光子能量）。答案也是以数值形式呈现的。 | 知识层次: 题目涉及基本公式（光子能量公式E=hc/λ）的直接应用和简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（E=hc/λ）进行计算，无需多个步骤或公式组合。题目提供了所有必要的信息，且计算过程简单直接，属于最基础的难度等级。", "convertible": true, "correct_option": "3.98 x 10^-19 j (2.48 ev)", "choice_question": "Visible light having a wavelength of 5 x 10^-7 m appears green. What is the energy of a photon of this light?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.98 x 10^-19 J (2.48 eV)", "B": "1.24 x 10^-19 J (0.77 eV)", "C": "6.63 x 10^-19 J (4.14 eV)", "D": "9.94 x 10^-19 J (6.20 eV)" }, "correct_answer": "A", "explanation": "正确答案A是通过E=hc/λ计算得出，其中h=6.626x10^-34 J·s，c=3x10^8 m/s，λ=5x10^-7 m。干扰项B是错误地将波长单位当作nm计算的结果，利用了单位混淆的认知偏差。干扰项C是错误地将普朗克常数h当作1x10^-33 J·s计算的结果，利用了常数记忆错误的直觉陷阱。干扰项D是错误地使用了E=2hc/λ计算的结果，利用了公式系数错误的多层次验证陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2160, "question": "If the surface of a single crystal copper is the {111} crystal plane, assuming that the crystal can slip on various slip systems. Discuss the possible morphology of slip lines on the surface (the orientation of slip lines and the angles between them).", "answer": "When the outer surface of a copper single crystal is the {111} family of crystal planes, the slip lines appearing on the surface are <110>, which are either parallel to each other or intersect at an angle of 60°.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求讨论单晶铜表面滑移线的可能形态（滑移线的取向和它们之间的角度），需要文字解释和论述，而不是选择、判断或计算。答案也提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目要求分析单晶铜在特定晶面（{111}）上的滑移线形态，涉及晶体滑移系统的选择和滑移线方向的确定。这需要理解晶体结构、滑移系统的基本原理，并能将这些概念应用于具体情境中。虽然不涉及复杂的计算或深度推理，但需要对多个概念进行关联和综合分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，需要考生掌握晶体滑移系统的基本概念，理解{111}晶面和<110>滑移方向的关系，并能综合分析滑移线在表面形成的可能形态（平行或60°夹角）。这需要将晶体学知识与实际观察现象进行多角度关联，并正确推导出结论，超出了简单记忆或单一概念应用的层次。", "convertible": true, "correct_option": "The slip lines are <110>, which are either parallel to each other or intersect at an angle of 60°.", "choice_question": "If the surface of a single crystal copper is the {111} crystal plane, assuming that the crystal can slip on various slip systems, what is the possible morphology of slip lines on the surface (the orientation of slip lines and the angles between them)?", "conversion_reason": "The answer is a standard description of the morphology of slip lines on the {111} crystal plane of copper, which can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip lines are <110> directions, forming 60° or 120° angles between them", "B": "Slip lines are <112> directions, forming 30° or 90° angles between them", "C": "Slip lines are <123> directions with variable angles depending on stress axis", "D": "Parallel slip lines only, as all {111}<110> slip systems project similarly" }, "correct_answer": "A", "explanation": "Correct answer is A because FCC slip occurs on <110> directions in {111} planes, which project as 60° or 120° angles on the (111) surface. Option B incorrectly uses <112> directions which are not active slip directions. Option C introduces an invalid higher-index slip direction. Option D is wrong because different <110> directions in the {111} plane project at 60° angles to each other on the surface.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1401, "question": "Determine whether the following statement is correct: The distinction between hot (deformation) working and cold (deformation) working of metals is based on the temperature of the deformation process.", "answer": "Incorrect", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错，答案直接给出了正确或错误的结论，符合判断题的特征。 | 知识层次: 题目考查对金属热加工和冷加工区分标准的基本概念记忆，属于定义性知识的判断。 | 难度: 该题目属于基础概念正误判断，仅需记忆热加工和冷加工的定义区别即可作答，无需深入理解或分析多个概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "Incorrect", "choice_question": "Determine whether the following statement is correct: The distinction between hot (deformation) working and cold (deformation) working of metals is based on the temperature of the deformation process.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials will eventually crystallize if held at a temperature just below their glass transition temperature for a sufficiently long time.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many amorphous materials can crystallize below their glass transition temperature (Tg) given enough time, this is not universally true for all amorphous materials. Some materials, particularly those with complex molecular structures or high kinetic barriers to crystallization, may remain amorphous indefinitely even below Tg. The statement incorrectly uses 'all' as an absolute qualifier, which is a common misconception in materials science where exceptions often exist.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1450, "question": "For a screw dislocation line, what is the relationship between its slip direction and the Burgers vector?", "answer": "Perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释螺位错线的滑移方向与伯格斯矢量之间的关系，答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目考查对螺位错基本性质的理解，即其滑移方向与伯氏矢量之间的关系，属于基础概念的记忆和理解范畴。 | 难度: 该题目属于基础概念记忆类型，仅需记住螺位错的滑移方向与伯格斯矢量之间的基本关系（垂直关系）。在选择题型中，这种直接考察定义或基本关系的题目属于最简单的等级1难度，不需要复杂的推理或分析过程。", "convertible": true, "correct_option": "Perpendicular", "choice_question": "For a screw dislocation line, what is the relationship between its slip direction and the Burgers vector?", "conversion_reason": "The answer is a standard term (Perpendicular), which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Parallel", "B": "Perpendicular", "C": "At 45° angle", "D": "Anti-parallel" }, "correct_answer": "B", "explanation": "For a screw dislocation, the Burgers vector is parallel to the dislocation line, making it perpendicular to the slip direction. Option A exploits the common confusion between edge and screw dislocations. Option C creates a plausible intermediate angle scenario. Option D introduces a directional relationship that seems logical but is incorrect for this case.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2816, "question": "Analyze the effect of polymer molecular weight on the viscous flow temperature", "answer": "When the molecular weight is smaller, the internal frictional resistance between molecular chains is reduced, making the relative movement of molecular chains easier, thus lowering the viscous flow temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求分析聚合物分子量对粘流温度的影响，需要文字解释和论述，答案也是以文字形式给出解释，符合简答题的特征。 | 知识层次: 题目要求分析聚合物分子量对粘流温度的影响，涉及分子链间摩擦阻力和相对运动的机理解释，需要理解分子量与粘流温度之间的关系，并进行综合分析。虽然不涉及复杂计算，但需要对概念进行关联和推理分析。 | 难度: 在选择题中属于中等难度，需要理解聚合物分子量对粘流温度的影响机制，涉及分子链间内摩擦阻力和相对运动的概念关联，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "When the molecular weight is smaller, the internal frictional resistance between molecular chains is reduced, making the relative movement of molecular chains easier, thus lowering the viscous flow temperature.", "choice_question": "Which of the following describes the effect of polymer molecular weight on the viscous flow temperature?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When the molecular weight is smaller, the internal frictional resistance between molecular chains is reduced, making the relative movement of molecular chains easier, thus lowering the viscous flow temperature.", "B": "Higher molecular weight polymers exhibit lower viscous flow temperatures due to increased chain entanglement facilitating segmental motion.", "C": "Viscous flow temperature is independent of molecular weight but directly proportional to the degree of crystallinity in the polymer.", "D": "The viscous flow temperature decreases with molecular weight up to the critical entanglement molecular weight, then increases due to reptation dynamics." }, "correct_answer": "A", "explanation": "Correct answer A accurately describes the inverse relationship between molecular weight and viscous flow temperature due to reduced chain friction. Option B reverses the relationship by incorrectly attributing easier motion to entanglements. Option C introduces a false crystallinity dependency, exploiting common confusion between thermal properties. Option D combines partially correct concepts (entanglement threshold) with misleading reptation effects, creating a complex but ultimately wrong scenario.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 479, "question": "7. What are the main structural types (subtypes) of silicate crystals?", "answer": "Island, group (or ring), chain, layer, framework", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举硅酸盐晶体的主要结构类型，答案需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目考查对硅酸盐晶体主要结构类型的基本分类记忆，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 该题目属于基础概念记忆类型，仅要求考生回忆并选择硅酸盐晶体的主要结构类型（岛状、群状/环状、链状、层状、框架状）。在选择题型中，这类直接考察定义和分类的记忆性知识属于最简单的难度等级，不需要任何解释、分析或推理过程。", "convertible": true, "correct_option": "Island, group (or ring), chain, layer, framework", "choice_question": "What are the main structural types (subtypes) of silicate crystals?", "conversion_reason": "The answer is a standard set of terms that can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Island, group, chain, layer, framework", "B": "Isolated, cyclic, single-chain, double-chain, sheet", "C": "Orthosilicate, metasilicate, phyllosilicate, tectosilicate", "D": "Monomer, dimer, oligomer, polymer, network" }, "correct_answer": "A", "explanation": "Correct answer A uses the standard classification terminology in crystallography. Option B introduces misleading terms like 'isolated' and 'cyclic' which are chemically plausible but not standard for silicate classification. Option C uses correct IUPAC terms for silicate subclasses but these describe chemical composition rather than structural types. Option D applies polymer chemistry terminology which is conceptually related but technically incorrect for crystalline structures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3521, "question": "Please specify the type of cast iron and heat treatment method that should be used for ball mill liners, and why?", "answer": "Ball mill liners: alloy nodular cast iron (such as medium manganese cast iron).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述特定材料的选择原因，答案需要文字说明而非简单选择或判断 | 知识层次: 题目要求选择特定类型的铸铁和热处理方法来满足球磨机衬板的使用需求，这需要理解不同铸铁材料的性能特点及其热处理工艺的影响，属于多概念关联和综合分析的应用层次。虽然不涉及复杂的计算或深度机理分析，但需要综合考虑材料选择与工艺匹配的合理性。 | 难度: 在选择题型内，该题目要求考生不仅掌握球磨机衬板材料的基本选择标准，还需要理解合金球墨铸铁（如中锰铸铁）的具体特性和适用原因。这涉及到多步概念关联和综合分析，包括材料性能、应用场景和热处理方法的匹配。虽然题目提供了正确选项，但考生仍需具备较深的知识储备和实际应用能力才能准确判断，因此属于较高难度等级。", "convertible": true, "correct_option": "alloy nodular cast iron (such as medium manganese cast iron)", "choice_question": "Which type of cast iron and heat treatment method should be used for ball mill liners?", "conversion_reason": "The answer is a standard term (alloy nodular cast iron), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Medium manganese nodular cast iron with austempering heat treatment", "B": "White cast iron with conventional quenching and tempering", "C": "Gray cast iron with stress relief annealing", "D": "High chromium cast iron with solution treatment and aging" }, "correct_answer": "A", "explanation": "Medium manganese nodular cast iron with austempering provides the optimal combination of hardness and toughness required for ball mill liners. The nodular graphite structure improves impact resistance while austempering produces bainitic microstructure for wear resistance. Option B is incorrect because white cast iron is too brittle despite its hardness. Option C is a cognitive bias trap - gray cast iron is commonly used but lacks the required wear resistance. Option D is a professional intuition trap - while high chromium cast iron has excellent wear resistance, its impact toughness is insufficient for this application.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 535, "question": "Syndiotactic", "answer": "Syndiotactic: A polymer in which the substituents are alternately attached to opposite sides of the main chain plane.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对术语进行文字解释和论述，没有提供选项或要求判断对错，也不需要数值计算 | 知识层次: 题目考查对\"Syndiotactic\"这一聚合物结构的基本定义和概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆，但需要考生准确理解并描述\"Syndiotactic\"的定义和特征，而不仅仅是简单的定义复述。题目要求考生能够解释聚合物中取代基的排列方式，这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "A polymer in which the substituents are alternately attached to opposite sides of the main chain plane.", "choice_question": "Which of the following best describes 'Syndiotactic'?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by presenting the definition as the correct option among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A polymer in which the substituents are alternately attached to opposite sides of the main chain plane", "B": "A polymer with random orientation of substituents relative to the main chain plane", "C": "A polymer where all substituents are on the same side of the main chain plane", "D": "A polymer with substituents arranged in a helical pattern around the main chain" }, "correct_answer": "A", "explanation": "The correct answer is A because syndiotactic polymers specifically have substituents alternating on opposite sides of the main chain. Option B describes atactic polymers, which is a common confusion. Option C describes isotactic polymers, another easily confused configuration. Option D mimics helical structures seen in some proteins but is irrelevant to syndiotacticity, playing on visual imagination biases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4608, "question": "Confirm that there are 2.2 Bohr magnetons associated with each iron atom, given that the saturation magnetization is 1.70 × 10^{6} \\mathrm{~A} / m, that iron has a BCC crystal structure, and that the unit cell edge length is 0.2866 nm.", "answer": "2.16 bohr magnetons/atom", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的物理参数（饱和磁化强度、晶体结构、晶胞边长）进行数值计算，最终得出每个铁原子的玻尔磁子数。解答过程需要应用相关公式和单位转换，属于典型的计算题。 | 知识层次: 题目需要进行多步计算，包括利用饱和磁化强度、晶体结构参数（BCC晶格常数）和单位体积原子数计算每个铁原子的磁矩，并转换为玻尔磁子单位。这涉及多个概念的综合应用和数值计算，但不需要复杂的推理或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要综合运用多个概念和公式进行计算。题目要求考生理解饱和磁化强度、BCC晶体结构、单位晶胞边长与原子数的关系，以及玻尔磁子与原子磁矩的转换。解题步骤包括计算单位体积内的铁原子数、推导每个原子的磁矩，最后转换为玻尔磁子单位。虽然选择题提供了正确选项，但解题过程涉及多步计算和单位转换，对概念理解和计算能力要求较高。", "convertible": true, "correct_option": "2.16 bohr magnetons/atom", "choice_question": "Confirm that the number of Bohr magnetons associated with each iron atom, given that the saturation magnetization is 1.70 × 10^{6} A/m, iron has a BCC crystal structure, and the unit cell edge length is 0.2866 nm, is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.16 bohr magnetons/atom", "B": "2.22 bohr magnetons/atom", "C": "1.91 bohr magnetons/atom", "D": "2.40 bohr magnetons/atom" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算得到的：对于BCC铁，每个晶胞有2个原子，体积为(0.2866 nm)^3。饱和磁化强度1.70×10^6 A/m转换为每个原子的磁矩为2.16 bohr magnetons。干扰项B利用了原始题目中的错误值2.2进行四舍五入；C是错误地使用了FCC结构的原子数计算；D则故意接近铁的纯自旋理论值2.4，但忽略了轨道角动量淬灭效应。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3402, "question": "What are the characteristics of carbon steel and alloy steel in terms of performance?", "answer": "Carbon steel is inferior to alloy steel in mechanical, physical, and chemical properties such as strength, wear resistance, toughness, and corrosion resistance.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释碳钢和合金钢在性能上的特点，答案提供了详细的文字论述，符合简答题的特征。 | 知识层次: 题目考查对碳钢和合金钢性能特点的基础概念记忆和理解，属于材料科学中钢材分类和基本性能的入门知识，不涉及复杂分析或综合应用。 | 难度: 该题目属于选择题型，要求考生比较碳钢和合金钢在性能上的特点。虽然涉及多个性能指标（强度、耐磨性、韧性、耐腐蚀性），但只需记忆和识别基本概念差异，无需深入分析或复杂推理。在选择题型中属于中等偏下的难度。", "convertible": true, "correct_option": "Carbon steel is inferior to alloy steel in mechanical, physical, and chemical properties such as strength, wear resistance, toughness, and corrosion resistance.", "choice_question": "Which of the following statements correctly compares the characteristics of carbon steel and alloy steel in terms of performance?", "conversion_reason": "The answer is a standard comparison between carbon steel and alloy steel, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Carbon steel exhibits higher thermal conductivity than alloy steel due to its simpler composition, but alloy steel surpasses it in all mechanical properties", "B": "While alloy steel generally has better corrosion resistance, carbon steel maintains superior toughness at cryogenic temperatures due to reduced interstitial effects", "C": "The yield strength of medium carbon steel (0.3-0.6% C) typically exceeds that of low-alloy steels (e.g., 4140) when both are in the annealed condition", "D": "Alloying elements in steel primarily improve machinability, while carbon content determines the ultimate tensile strength regardless of heat treatment" }, "correct_answer": "A", "explanation": "Correct answer A is accurate because while carbon steel does have higher thermal conductivity (due to fewer alloying elements disrupting phonon transport), alloy steels are superior in mechanical properties through mechanisms like solid solution strengthening and precipitation hardening. Option B exploits cryogenic properties intuition but is incorrect - alloy steels maintain better toughness at low temperatures. Option C uses a specific condition trap (annealed state) where medium carbon steel can momentarily appear stronger. Option D creates a false dichotomy between alloying elements and carbon content, oversimplifying their synergistic effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4085, "question": "As the porosity of refractory ceramic bricks increases, what happens to the thermal insulation?", "answer": "Thermal insulation increases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释孔隙率增加对隔热性能的影响，答案需要文字解释和论述，而不是选择或判断。 | 知识层次: 题目考查对多孔材料热绝缘性能与孔隙率关系的基本概念理解，属于基础概念记忆和简单应用范畴 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即孔隙率增加对隔热性能的影响。正确选项直接对应基本原理，无需复杂推理或概念整合，属于最基础的难度等级。", "convertible": true, "correct_option": "Thermal insulation increases", "choice_question": "As the porosity of refractory ceramic bricks increases, what happens to the thermal insulation?", "conversion_reason": "The answer is a standard statement that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermal insulation increases due to increased air pockets acting as insulators", "B": "Thermal insulation decreases because porosity reduces structural integrity", "C": "Thermal conductivity increases proportionally with porosity", "D": "No significant change occurs as porosity affects mechanical properties more than thermal properties" }, "correct_answer": "A", "explanation": "The correct answer is A because air pockets in porous materials significantly reduce heat transfer. Option B exploits the cognitive bias linking structural integrity with thermal properties. Option C uses a common misconception that porosity directly correlates with conductivity. Option D creates confusion by suggesting porosity only affects mechanical properties, which is a partial truth but ignores thermal effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4315, "question": "For 11.20 kg of a magnesium-lead alloy of composition 30 wt% Pb-70 wt% Mg, is it possible, at equilibrium, to have α and Mg2Pb phases having respective masses of 7.39 kg and 3.81 kg?", "answer": "yes, it is possible to have a 30 wt% pb-70 wt% mg alloy with masses of 7.39 kg and 3.81 kg for the α and mg2pb phases, respectively.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断在特定条件下是否可能达到某种相平衡状态，答案只需回答\"yes\"或\"no\"即可，属于典型的判断题形式。 | 知识层次: 题目需要应用相图知识进行多步计算，涉及相的质量分数计算和相平衡的判断，需要综合分析合金成分与相组成的关系。 | 难度: 在选择题型中，该题目属于较高难度，需要综合运用相图知识、质量平衡计算和相组成分析。解题过程涉及多步计算（如确定各相组成和验证质量平衡）以及概念关联（如理解α相和Mg2Pb相在相图中的位置）。虽然题目提供了正确选项，但学生仍需进行综合分析才能判断其正确性，这超出了简单的概念回忆或单步计算，属于中等应用层次的要求。", "convertible": true, "correct_option": "yes, it is possible to have a 30 wt% pb-70 wt% mg alloy with masses of 7.39 kg and 3.81 kg for the α and mg2pb phases, respectively.", "choice_question": "For 11.20 kg of a magnesium-lead alloy of composition 30 wt% Pb-70 wt% Mg, is it possible, at equilibrium, to have α and Mg2Pb phases having respective masses of 7.39 kg and 3.81 kg?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "For a magnesium-lead alloy with 30 wt% Pb and 70 wt% Mg, the α phase always contains less than 25 wt% Pb at equilibrium.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because the composition of the α phase varies with temperature. At some temperatures, the α phase can indeed contain more than 25 wt% Pb. The use of 'always' makes this statement incorrect. A common misconception is assuming fixed composition ranges for phases regardless of temperature conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4118, "question": "Compared to other ceramic materials, do ceramic-matrix composites have better stability at elevated temperatures?", "answer": "The answer is not provided in the given information.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（陶瓷基复合材料在高温下是否比其他陶瓷材料具有更好的稳定性），答案形式为判断性结论 | 知识层次: 题目考查对陶瓷基复合材料在高温下稳定性的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即陶瓷基复合材料在高温下的稳定性与其他陶瓷材料的比较。题目要求的是对定义或分类的基本记忆，不需要深入理解或分析多个概念。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "The answer is not provided in the given information.", "choice_question": "Compared to other ceramic materials, do ceramic-matrix composites have better stability at elevated temperatures?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic-matrix composites exhibit superior thermal stability compared to monolithic ceramics at temperatures above 1500°C.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramic-matrix composites do show improved thermal stability, the use of 'all' makes this statement false. Performance depends on specific matrix/reinforcement combinations, processing methods, and environmental conditions. Some monolithic ceramics like alumina or zirconia may outperform certain composites in specific high-temperature scenarios.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 997, "question": "Please briefly describe the mechanism of high-temperature recovery and its driving force", "answer": "High-temperature mechanism: corresponds to polygonization (dislocation slip + climb). Driving force: release of stored energy (mainly lattice distortion energy) generated during cold deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要描述高温回复的机制及其驱动力，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目要求解释高温回复的机制及其驱动力，涉及位错滑移和攀移等多重概念的综合运用，需要深入理解材料变形和能量释放的机理，属于对知识点的复杂分析和推理解释。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解高温回复的机制（多边形化过程，涉及位错滑移和攀移），还需要准确识别其驱动力（冷变形储存能的释放，主要是晶格畸变能）。这需要考生具备将多个复杂概念（位错理论、能量释放原理、变形机制）综合运用的能力，并进行机理层面的深度解释。选择题型中能够完整回答这种综合机理分析题的选项非常少见，对知识整合和推理能力要求极高。", "convertible": true, "correct_option": "High-temperature mechanism: corresponds to polygonization (dislocation slip + climb). Driving force: release of stored energy (mainly lattice distortion energy) generated during cold deformation.", "choice_question": "Which of the following correctly describes the mechanism of high-temperature recovery and its driving force?", "conversion_reason": "The answer is a standard description of a scientific concept, which can be converted into a multiple-choice format by presenting it as the correct option among possible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High-temperature mechanism: corresponds to polygonization (dislocation slip + climb). Driving force: release of stored energy (mainly lattice distortion energy) generated during cold deformation", "B": "High-temperature mechanism: involves recrystallization and grain growth. Driving force: reduction of interfacial energy through grain boundary migration", "C": "High-temperature mechanism: dominated by vacancy diffusion. Driving force: minimization of free energy through entropy maximization", "D": "High-temperature mechanism: involves dislocation annihilation through cross-slip. Driving force: reduction of strain energy in the crystal lattice" }, "correct_answer": "A", "explanation": "The correct answer is A because high-temperature recovery specifically involves polygonization through both dislocation slip and climb, with the driving force being the release of stored energy from cold deformation. Option B incorrectly describes recrystallization rather than recovery. Option C focuses on vacancy diffusion which is more relevant to annealing than recovery. Option D describes a partial mechanism (cross-slip) but misses the critical climb component and misidentifies the driving force.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3379, "question": "What is the role of carbon and alloying elements in high-speed steel?", "answer": "The purpose of high carbon content is to form carbides with carbide-forming elements such as Cr, W, Mo, and V, and to ensure a strong martensitic matrix to enhance the hardness and wear resistance of the steel. W, Mo, and V primarily improve the red hardness of the steel, as the carbides formed by these elements have high hardness and produce a 'secondary hardening' effect, thereby significantly enhancing the steel's red hardness, hardness, and wear resistance. Cr mainly improves the hardenability of the steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释碳和合金元素在高速钢中的作用，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释碳和合金元素在高速钢中的作用，涉及多个元素的协同效应和机理解释，需要综合分析不同元素对钢性能的影响，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求考生理解高碳钢和合金元素的基本作用，还需要综合分析不同元素（如Cr、W、Mo、V）在高速钢中的具体功能及其相互作用。题目涉及多个概念（如碳化物形成、马氏体基体、红硬性、二次硬化效应等），并要求考生将这些概念关联起来，进行多角度分析。此外，解题步骤较为复杂，需要考生具备较强的材料科学知识背景和综合分析能力。", "convertible": true, "correct_option": "The purpose of high carbon content is to form carbides with carbide-forming elements such as Cr, W, Mo, and V, and to ensure a strong martensitic matrix to enhance the hardness and wear resistance of the steel. W, Mo, and V primarily improve the red hardness of the steel, as the carbides formed by these elements have high hardness and produce a 'secondary hardening' effect, thereby significantly enhancing the steel's red hardness, hardness, and wear resistance. Cr mainly improves the hardenability of the steel.", "choice_question": "What is the role of carbon and alloying elements in high-speed steel?", "conversion_reason": "The answer is a standard explanation of the role of carbon and alloying elements in high-speed steel, which can be directly used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Carbon forms carbides with W/Mo/V to create secondary hardening, while Cr enhances hardenability", "B": "Carbon primarily increases ductility, while alloying elements reduce the steel's thermal conductivity", "C": "Carbon content is minimized to prevent brittleness, while alloying elements mainly improve corrosion resistance", "D": "Carbon stabilizes austenite phase, while alloying elements lower the eutectoid temperature" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the carbide formation and secondary hardening mechanism. Option B incorrectly states carbon increases ductility (it actually reduces it) and misrepresents the primary role of alloying elements. Option C is wrong about minimizing carbon (high-speed steel requires high carbon) and misidentifies the main purpose of alloying. Option D inaccurately describes carbon's role (it promotes martensite, not austenite stability) and oversimplifies alloying elements' effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1169, "question": "What type of solid solution is ferrite?", "answer": "Interstitial", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述铁素体的固溶体类型，答案\"Interstitial\"是一个术语性的简短回答，属于需要专业知识解释的简答题类型 | 知识层次: 题目考查对铁素体类型的基本概念记忆，属于基础分类知识的直接回忆 | 难度: 该题目属于基础概念记忆类型，仅需识别铁素体（ferrite）属于间隙式固溶体（Interstitial）这一基本定义。选择题型中无需复杂推理或概念比较，属于最基础的定义简答级别。", "convertible": true, "correct_option": "Interstitial", "choice_question": "What type of solid solution is ferrite?", "conversion_reason": "The answer is a standard term (Interstitial), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial", "B": "Substitutional", "C": "Intermetallic", "D": "Eutectic" }, "correct_answer": "A", "explanation": "Ferrite is an interstitial solid solution where carbon atoms occupy the interstitial sites in the BCC iron lattice. Option B (Substitutional) is incorrect but tempting because many solid solutions involve substitutional atoms. Option C (Intermetallic) exploits the common confusion between solid solutions and intermetallic compounds. Option D (Eutectic) is a phase mixture, not a solid solution type, designed to trap those who confuse microstructure types with atomic-scale solutions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 624, "question": "According to the influence of cooling rate on metal microstructure, how should the solidification be controlled to obtain metastable phases?", "answer": "To obtain metastable phases, the cooling rate must far exceed the equilibrium cooling rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释如何通过控制凝固过程获得亚稳相，答案需要文字论述而非选择、判断或计算 | 知识层次: 题目要求理解冷却速率对金属微观结构的影响，并应用这一知识来论述如何通过控制凝固过程获得亚稳相。这需要将多个概念（冷却速率、平衡冷却速率、亚稳相）关联起来，并进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解金属微观结构受冷却速率影响的基本概念，并能将冷却速率与亚稳态相的形成关联起来。虽然题目涉及多步计算和概念关联，但在选择题型中，正确选项直接给出了关键结论，减少了分析步骤的复杂性。", "convertible": true, "correct_option": "The cooling rate must far exceed the equilibrium cooling rate.", "choice_question": "According to the influence of cooling rate on metal microstructure, how should the solidification be controlled to obtain metastable phases?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The cooling rate must far exceed the equilibrium cooling rate", "B": "The cooling rate should match the equilibrium phase diagram conditions", "C": "A slow cooling rate is required to allow sufficient diffusion time", "D": "The cooling rate should be precisely at the eutectic point of the alloy system" }, "correct_answer": "A", "explanation": "Correct answer A is based on the fundamental principle that metastable phases form when kinetic conditions prevent the system from reaching thermodynamic equilibrium. Option B exploits the common misconception that phase diagrams directly dictate all solidification outcomes. Option C uses reverse psychology by suggesting a slow cooling process which actually promotes equilibrium phases. Option D creates a numerical trap by referencing a specific but irrelevant point on phase diagrams.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3809, "question": "Consider a Pb-35% Sn alloy. Determine if the alloy is hypoeutectic or hypereutectic.", "answer": "hypoeutectic", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过分析合金成分来判断其类型（hypoeutectic或hypereutectic），需要基于相图知识进行解释和论述，而不是简单的选择或计算。答案虽然简短，但需要理解合金成分与共晶点之间的关系。 | 知识层次: 题目考查对合金分类（hypoeutectic或hypereutectic）的基本概念记忆和理解，仅需根据给定的成分百分比与共晶点比较即可判断，无需复杂计算或分析。 | 难度: 在选择题型中，该题目仅需记忆Pb-Sn合金相图中35% Sn的组成位置相对于共晶点的关系，属于基础定义简答。无需解释或复杂分析，只需识别hypoeutectic的定义即可作答。", "convertible": true, "correct_option": "hypoeutectic", "choice_question": "Consider a Pb-35% Sn alloy. Is the alloy hypoeutectic or hypereutectic?", "conversion_reason": "The answer is a standard term (hypoeutectic), which can be presented as a choice in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hypoeutectic (Sn content below eutectic composition)", "B": "Hypereutectic (Sn content above eutectic composition)", "C": "Eutectic (exactly at the eutectic composition)", "D": "Peritectic (undergoes peritectic reaction instead)" }, "correct_answer": "A", "explanation": "The correct answer is A because the eutectic composition for Pb-Sn system is 61.9% Sn, and 35% Sn is below this value. B is incorrect but tempting because 35% seems high numerically. C is incorrect but exploits the common misconception that intermediate compositions are eutectic. D is a completely unrelated phase reaction type included to test fundamental concept clarity.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1856, "question": "Give two examples of forming continuous substitutional solid solutions", "answer": "PbTiO3-PbZrO3, albite-orthoclase, MgO-NiO, etc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出两个连续置换固溶体的例子，答案需要列举具体的材料组合，属于需要文字回答的简答题类型。 | 知识层次: 题目考查对连续置换固溶体基本概念的记忆和理解，只需列举典型例子，不需要深入分析或综合应用。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目要求列举两个形成连续置换固溶体的例子，这只需要学生对相关基础概念的记忆，无需深入解释或分析。正确选项直接提供了几个常见的例子，学生只需识别或回忆这些例子即可作答，解题步骤简单，对知识点掌握深度的要求较低。", "convertible": true, "correct_option": "PbTiO3-PbZrO3, albite-orthoclase, MgO-NiO", "choice_question": "Which of the following are examples of forming continuous substitutional solid solutions?", "conversion_reason": "The answer is a standard set of terms that can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "PbTiO3-PbZrO3", "B": "Fe-C (steel system)", "C": "Al2O3-Cr2O3", "D": "Cu-Zn (brass system)" }, "correct_answer": "A", "explanation": "The correct answer is A because PbTiO3-PbZrO3 forms continuous solid solutions due to similar ionic radii and crystal structures. Option B is a cognitive bias trap - while Fe-C is important in steel, it forms interstitial not substitutional solutions. Option C is a professional intuition trap - though both are oxides, their crystal structures differ preventing complete solubility. Option D is a multi-level verification trap - while Cu-Zn forms substitutional solutions, they are limited (brass) not continuous.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2180, "question": "How is fibrous structure formed?", "answer": "After cold working of materials, in addition to transforming the disordered orientation of polycrystalline materials into materials with preferred orientation, it also causes deformation of insoluble impurities, second phases, and various defects in the material. Since grains, impurities, second phases, and defects are all elongated into fibrous shapes along the main deformation direction of the metal, it is called fibrous structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释纤维状结构的形成过程，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目不仅要求解释纤维结构的形成过程，还需要理解冷加工对材料微观结构的影响，包括晶粒、杂质、第二相和缺陷的变形机制。这需要综合运用材料科学的知识，进行推理分析和机理解释，思维过程的深度要求较高。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解冷加工对材料微观结构的影响，还需要综合运用多方面的知识（包括晶粒取向、杂质、第二相和缺陷的变形机制）来解释纤维状结构的形成机理。这种复杂现象的分析和机理解释在选择题中属于最高认知层次的要求，需要考生具备深入的材料科学知识和综合推理能力。", "convertible": true, "correct_option": "After cold working of materials, in addition to transforming the disordered orientation of polycrystalline materials into materials with preferred orientation, it also causes deformation of insoluble impurities, second phases, and various defects in the material. Since grains, impurities, second phases, and defects are all elongated into fibrous shapes along the main deformation direction of the metal, it is called fibrous structure.", "choice_question": "How is fibrous structure formed?", "conversion_reason": "The answer is a standard explanation of the concept, which can be used as the correct option in a multiple-choice question. The question can be kept as is for the multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "After cold working, grains and defects elongate along deformation direction forming fiber-like morphology", "B": "During rapid solidification, directional dendrite growth creates aligned fibrous microstructure", "C": "High-temperature annealing causes recrystallization into columnar grain structures", "D": "Electrospinning polymer solutions produces nanoscale fiber assemblies" }, "correct_answer": "A", "explanation": "Correct answer A describes the true metallurgical process where cold working induces fibrous structure through mechanical deformation. B exploits confusion with solidification structures (dendrites ≠ fibers). C uses a plausible high-temperature process but describes columnar grains, not true fibrous structure. D is a red herring from polymer processing that sounds technologically relevant but is unrelated to metallic fibrous structure formation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1243, "question": "According to the phase rule, what is the maximum number of equilibrium phases in a binary system?", "answer": "17", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据相规则回答二元系统中平衡相的最大数量，需要理论知识的文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目考查对相律这一基本原理的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对相律基础定义的记忆，无需解释或分析。学生只需回忆\"二元系统中最大平衡相数\"这一基本概念即可直接选择正确答案，属于最基础的定义简答类型。", "convertible": true, "correct_option": "17", "choice_question": "According to the phase rule, what is the maximum number of equilibrium phases in a binary system?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "选项B", "C": "17", "D": "选项D" }, "correct_answer": "C", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 3606, "question": "Determine the planar density for BCC lithium in the (110) plane.", "answer": "planar density = 0.1149 x 10^16 points/cm^2", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算BCC锂在(110)晶面上的平面密度，需要通过数值计算和公式应用来得出具体数值结果。答案以数值形式给出，符合计算题的特征。 | 知识层次: 题目需要理解BCC晶体结构、(110)平面的原子排列，并应用平面密度计算公式进行多步计算，涉及概念关联和综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构、(110)晶面原子排列、平面密度计算公式等多个概念，并进行多步骤计算（包括晶格常数推导、有效原子数计算、面积计算等综合步骤）。虽然题目提供了正确选项减少了推导负担，但仍需较强的空间想象能力和计算准确性，属于需要综合分析的应用题。", "convertible": true, "correct_option": "0.1149 x 10^16 points/cm^2", "choice_question": "What is the planar density for BCC lithium in the (110) plane?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1149 x 10^16 points/cm^2", "B": "0.0724 x 10^16 points/cm^2", "C": "0.1443 x 10^16 points/cm^2", "D": "0.0574 x 10^16 points/cm^2" }, "correct_answer": "A", "explanation": "The correct answer A is calculated by considering the (110) plane in BCC lithium, where the planar density is determined by the number of atoms per unit area. Option B is a common error from incorrectly calculating the area by using the face diagonal instead of the correct planar dimensions. Option C is a trap for those who mistakenly use FCC planar density calculation. Option D is half the correct value, targeting those who forget to account for both atoms in the (110) plane unit cell.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1882, "question": "When a small amount of CaO is doped into ThO2, write the corresponding solid solution formula (9)", "answer": "9) Th1-xCaxO2-x", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求写出相应的固溶体化学式，需要根据掺杂规则进行推导和书写，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目需要理解掺杂过程中的电荷平衡原理，并能够正确应用缺陷化学的知识来推导固溶体化学式。这涉及到多步的思考和概念关联，而不仅仅是简单的记忆或直接套用公式。 | 难度: 在选择题中属于中等难度，需要理解掺杂固溶体的基本概念，掌握电荷平衡原理，并能正确推导出固溶体化学式。题目涉及多步计算和概念关联，但选项提供了明确的结构指引，降低了纯推导的难度。", "convertible": true, "correct_option": "Th1-xCaxO2-x", "choice_question": "When a small amount of CaO is doped into ThO2, what is the corresponding solid solution formula?", "conversion_reason": "The answer is a standard chemical formula, which can be presented as a choice in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Th1-xCaxO2-x", "B": "Th1-xCaxO2", "C": "ThO2-xCax", "D": "(Th,Ca)O2" }, "correct_answer": "A", "explanation": "The correct answer is A because when CaO (which has a +2 cation) is doped into ThO2 (where Th is +4), charge compensation requires the creation of oxygen vacancies, leading to the formula Th1-xCaxO2-x. Option B is incorrect because it ignores the necessary charge compensation. Option C is wrong as it incorrectly places Ca in the anion site. Option D is a common oversimplification that fails to account for the defect chemistry involved.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3875, "question": "Describe the hardness and microstructure in an eutectoid steel that has been heated to 700^{\\circ} C, quenched to 650^{\\circ} C and held for 500s, and finally quenched to room temperature.", "answer": "HRC =25 and the microstructure is all pearlite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述材料的硬度和微观结构，需要文字解释和论述，答案也是以文字形式给出。 | 知识层次: 题目要求描述特定热处理条件下共析钢的硬度和显微组织，涉及对热处理工艺、相变过程以及显微组织与性能关系的理解和应用。需要将热处理步骤与相变动力学和显微组织演变联系起来，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及钢的热处理过程、相变行为以及最终组织和硬度的预测，要求考生能够综合运用相关知识，分析不同温度下的相变过程，并正确判断最终的组织和硬度。虽然题目提供了具体的温度和时间参数，但考生仍需具备一定的综合分析能力才能正确选择答案。", "convertible": true, "correct_option": "HRC =25 and the microstructure is all pearlite.", "choice_question": "What are the hardness and microstructure in an eutectoid steel that has been heated to 700°C, quenched to 650°C and held for 500s, and finally quenched to room temperature?", "conversion_reason": "The answer is a standard and specific description, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "HRC =25 and the microstructure is all pearlite", "B": "HRC =45 and the microstructure is bainite with some martensite", "C": "HRC =65 and the microstructure is fully martensitic", "D": "HRC =15 and the microstructure is spheroidized cementite in ferrite matrix" }, "correct_answer": "A", "explanation": "The correct answer is A because heating to 700°C puts the steel in the austenite phase field, quenching to 650°C is above the eutectoid temperature (allowing full austenitization), and holding for 500s at 650°C allows complete pearlite transformation (not enough time for bainite formation). Final quenching to room temperature doesn't change the microstructure. Option B is a cognitive bias trap - the temperature/time combination is insufficient for bainite formation. Option C exploits the common misconception that any quenching leads to martensite. Option D mimics a spheroidization treatment but the temperature/time parameters are incorrect for this process.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3864, "question": "A steel contains 55% \\alpha and 45% \\gamma at 750^{\\circ} C. Estimate the carbon content of the steel.", "answer": "the carbon content of the steel is 0.281% C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算估计钢的碳含量，答案是一个具体的数值结果（0.281% C），解答过程需要应用材料科学中的相图或相关公式进行计算。 | 知识层次: 题目需要应用铁碳相图的知识，通过给定的相比例和温度来估算碳含量，涉及多步计算和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图中α和γ相的比例关系，并能正确应用杠杆定律进行多步计算。虽然题目给出了具体温度（750°C）简化了部分分析步骤，但仍需要考生综合运用相图知识和计算能力才能得出正确答案。相比单纯的概念题或单步计算题，这类题目对知识掌握深度和计算能力的要求更高，但尚未达到复杂多变量计算的难度。", "convertible": true, "correct_option": "0.281% C", "choice_question": "A steel contains 55% \\alpha and 45% \\gamma at 750^{\\circ} C. What is the estimated carbon content of the steel?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.281% C", "B": "0.68% C", "C": "0.45% C", "D": "0.77% C" }, "correct_answer": "A", "explanation": "正确答案A是通过铁碳相图在750°C时α相和γ相的比例精确计算得出的。干扰项B利用了常见的认知偏差，将相比例直接转换为碳含量百分比。干扰项C设计为γ相比例的直接数值，利用了直觉陷阱。干扰项D采用了共析点碳含量，虽然相关但在当前温度下不适用。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4297, "question": "A large plate is fabricated from a steel alloy that has a plane strain fracture toughness of 55 MPa \\sqrt{m}(50 ksi \\sqrt{in}.). If, during service use, the plate is exposed to a tensile stress of 200 MPa(29,000 psi), determine the minimum length of a surface crack that will lead to fracture. Assume a value of 1.0 for Y.", "answer": "the minimum length of a surface crack that will lead to fracture is 0.024 \\, m (24 mm).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定表面裂纹的最小长度，答案是一个具体的数值结果（0.024 m），这表明解答过程涉及计算步骤。 | 知识层次: 题目主要考查基本公式的应用和简单计算，涉及平面应变断裂韧性和应力强度因子的直接套用，思维过程较为直接，无需多步计算或综合分析。 | 难度: 在选择题中属于简单难度，题目要求直接应用平面应变断裂韧性公式（K_IC = Y * σ * sqrt(πa)）进行简单计算，仅需一步代数变形即可求解裂纹长度a。虽然涉及单位转换和公式理解，但步骤直接且无需多步推导或复杂分析。", "convertible": true, "correct_option": "0.024 m (24 mm)", "choice_question": "A large plate is fabricated from a steel alloy that has a plane strain fracture toughness of 55 MPa √m (50 ksi √in.). If, during service use, the plate is exposed to a tensile stress of 200 MPa (29,000 psi), what is the minimum length of a surface crack that will lead to fracture? Assume a value of 1.0 for Y.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.024 m (24 mm)", "B": "0.012 m (12 mm)", "C": "0.048 m (48 mm)", "D": "0.006 m (6 mm)" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the fracture toughness formula: K_IC = Yσ√(πa), where K_IC is the plane strain fracture toughness (55 MPa√m), Y is the geometric factor (1.0), σ is the tensile stress (200 MPa), and a is the crack length. Solving for a gives 0.024 m. Option B is half the correct value, exploiting the common mistake of not squaring the terms in the formula. Option C is double the correct value, targeting those who might confuse the relationship between stress and crack length. Option D is one-fourth the correct value, designed to trap those who might incorrectly apply a safety factor or misremember the formula's exponent.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4823, "question": "What is the principal difference between natural and artificial aging processes?", "answer": "For precipitation hardening, natural aging is allowing the precipitation process to occur at the ambient temperature; artificial aging is carried out at an elevated temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释自然时效和人工时效的主要区别，答案以文字形式进行解释和论述，没有提供选项或要求判断对错，也不需要数值计算。 | 知识层次: 题目考查对自然时效和人工时效两种工艺的基本定义和区别的记忆与理解，属于基础概念层次的知识点。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解并区分自然老化和人工老化的定义及其在沉淀硬化过程中的不同应用。正确选项提供了明确的对比解释，但考生仍需掌握相关背景知识才能准确作答。相较于仅要求记忆单一定义的等级1题目，此题要求考生对两个相关概念进行解释和描述，因此属于等级2难度。", "convertible": true, "correct_option": "For precipitation hardening, natural aging is allowing the precipitation process to occur at the ambient temperature; artificial aging is carried out at an elevated temperature.", "choice_question": "What is the principal difference between natural and artificial aging processes?", "conversion_reason": "The answer is a standard explanation of the difference between natural and artificial aging processes, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Natural aging occurs at ambient temperature while artificial aging requires elevated temperatures to accelerate precipitation kinetics", "B": "Natural aging relies on vacancy diffusion whereas artificial aging is driven by dislocation climb mechanisms", "C": "Artificial aging produces finer precipitates due to higher nucleation rates at elevated temperatures", "D": "Natural aging achieves full thermodynamic equilibrium while artificial aging results in metastable phases" }, "correct_answer": "A", "explanation": "The correct answer A precisely distinguishes the temperature difference between natural and artificial aging processes. Option B incorrectly associates aging with dislocation mechanisms rather than precipitation. Option C contains partial truth about nucleation rates but fails to capture the fundamental temperature difference. Option D reverses the thermodynamic states - artificial aging actually approaches equilibrium faster while natural aging often stops at metastable states.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2251, "question": "During the solid-state phase transformation, assuming the nucleation rate $\\\\dot{N}$ and growth rate $G$ are constants, the volume fraction of the new phase formed after time $t$ can be obtained using the Johnson-Mehl equation, i.e., $$ \\\\begin{array}{r}{\\\\varphi=1-\\\\exp\\\\left(-\\\\frac{\\\\pi}{3}\\\\dot{N}G^{3}t^{4}\\\\right)}\\\\end{array}$$ Given the nucleation rate $\\\\dot{N}=1~000/(\\\\mathrm{cm}^{3}\\\\bullet\\\\mathrm{s}),G=3\\\\times10^{5}~\\\\mathrm{cm/s},$ calculate the time required to achieve a $50\\\\%$ transformation.", "answer": "$$ \\\\varphi=1-\\\\exp\\\\Bigl(-\\\\textstyle{\\\\frac{\\\\pi}{3}}\\\\dot{N}G^{3}t^{4}\\\\Bigr)$$ $$ 50\\\\%=1-\\\\exp\\\\Bigl(-\\\\frac{\\\\pi}{3}\\\\dot{N}G^{3}t^{4}\\\\Bigr)$$ $$ 0.6931={\\\\frac{\\\\pi}{3}}\\\\times1000\\\\times(3\\\\times10^{-5})^{3}t^{4}$$ $$ t^{4}=2.45\\\\times10^{10}$$ $$ t=395\\\\mathrm{~s~}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出具体的时间数值。解答过程涉及公式变换和数值运算，符合计算题的特征。 | 知识层次: 题目需要应用Johnson-Mehl方程进行多步计算，涉及对数运算和指数函数的转换，需要理解相变动力学的基本原理并正确代入数值进行计算，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要理解Johnson-Mehl方程的概念，并进行多步骤的计算和转换。题目涉及对数运算、指数函数处理以及单位换算，虽然计算过程明确但步骤较多，对学生的综合计算能力和概念理解有一定要求。", "convertible": true, "correct_option": "395 s", "choice_question": "During the solid-state phase transformation, assuming the nucleation rate $\\dot{N}$ and growth rate $G$ are constants, the volume fraction of the new phase formed after time $t$ can be obtained using the Johnson-Mehl equation, i.e., $$ \\begin{array}{r}{\\varphi=1-\\exp\\left(-\\frac{\\pi}{3}\\dot{N}G^{3}t^{4}\\right)}\\end{array}$$ Given the nucleation rate $\\dot{N}=1~000/(\\mathrm{cm}^{3}\\bullet\\mathrm{s}),G=3\\times10^{5}~\\mathrm{cm/s},$ what is the time required to achieve a $50\\%$ transformation?", "conversion_reason": "The calculation leads to a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "395 s", "B": "1.25 × 10^4 s", "C": "2.37 × 10^-3 s", "D": "7.94 × 10^5 s" }, "correct_answer": "A", "explanation": "The correct answer is derived by solving the Johnson-Mehl equation for 50% transformation (φ=0.5). Option B results from incorrectly assuming linear instead of exponential kinetics. Option C arises from unit conversion errors with the high growth rate. Option D comes from mishandling the t^4 term in the exponential. The correct calculation requires precise handling of both the exponential form and the t^4 dependence.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 738, "question": "Which valence state of cations must be present in the exchange of originally adsorbed cations in clay for mud peptization? (d) Monovalent (e) Divalent (f) Trivalent", "answer": "d", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项（d、e、f）中选择一个正确答案（d），符合选择题的特征 | 知识层次: 题目考查粘土中阳离子交换的基本概念，即单价阳离子在泥浆胶溶中的作用，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于基础概念记忆层次，仅需识别黏土中阳离子交换的基本原理（单价阳离子促进泥浆胶溶）。题目直接给出定义性知识，无需理解或辨析其他选项的化学意义，属于最简单的概念识别题。", "convertible": true, "correct_option": "d", "choice_question": "Which valence state of cations must be present in the exchange of originally adsorbed cations in clay for mud peptization?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The presence of divalent cations (e.g., Ca2+) is essential for peptization due to their strong bridging effect between clay layers", "B": "Trivalent cations (e.g., Al3+) are required as they provide optimal charge density for colloidal stability", "C": "A mixture of mono- and divalent cations creates the ideal balance between dispersion and flocculation", "D": "Monovalent cations (e.g., Na+) are necessary to maximize double layer repulsion between particles" }, "correct_answer": "D", "explanation": "The correct answer is D because monovalent cations (like Na+) maximize the double layer repulsion between clay particles, which is essential for peptization. This creates sufficient electrostatic repulsion to overcome van der Waals attraction. Option A is a cognitive bias trap - while divalent cations do bridge clay layers, this actually promotes flocculation rather than peptization. Option B exploits professional intuition by suggesting trivalent cations would be best due to their high charge, but in reality they cause too much flocculation. Option C is a multi-level verification trap that seems plausible by suggesting a balance, but in fact monovalent cations alone provide the best peptization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3350, "question": "To predict the normalizing effect of φ25 eutectoid steel bars, how applicable is the continuous cooling transformation curve?", "answer": "To predict the microstructure and hardness after cooling, the continuous cooling transformation curve should be used, as normalizing is a continuous cooling process.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释连续冷却转变曲线在预测正火效果中的适用性，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求将连续冷却转变曲线应用于预测正火效果，涉及概念关联和综合分析，需要理解正火过程与连续冷却转变曲线的关系，并应用该知识进行预测。 | 难度: 在选择题中属于中等难度，需要理解连续冷却转变曲线的应用场景，并能将其与正火工艺（连续冷却过程）关联起来。题目要求考生不仅知道连续冷却转变曲线的基本概念，还要能综合分析其在预测显微组织和硬度方面的适用性。这种题目涉及多步概念关联和综合分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "To predict the microstructure and hardness after cooling, the continuous cooling transformation curve should be used, as normalizing is a continuous cooling process.", "choice_question": "To predict the normalizing effect of φ25 eutectoid steel bars, how applicable is the continuous cooling transformation curve?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The continuous cooling transformation curve is essential for predicting microstructure evolution during normalizing", "B": "The isothermal transformation diagram should be used instead, as normalizing involves holding at elevated temperature", "C": "Neither is needed since eutectoid steels always form pearlite during normalizing", "D": "Both curves are equally applicable as they show identical transformation behavior" }, "correct_answer": "A", "explanation": "The correct answer is A because normalizing is a continuous cooling process, making the CCT curve essential for predicting microstructure evolution. Option B exploits the common confusion between isothermal and continuous cooling processes. Option C creates a cognitive trap by oversimplifying eutectoid steel behavior. Option D is a professional intuition trap suggesting equivalence between fundamentally different transformation diagrams.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 428, "question": "6.Common methods for strengthening metal materials include: (14)", "answer": "Solid solution strengthening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举金属材料强化的常见方法，需要文字解释和论述，而不是从给定选项中选择或判断对错 | 知识层次: 题目考查金属材料强化方法的基本概念记忆，属于基础概念记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对金属材料强化方法的基础概念记忆，属于最基本的定义简答级别。学生只需识别\"固溶强化\"这一基本术语即可作答，无需进行概念解释或复杂分析，符合等级1的简单记忆要求。", "convertible": true, "correct_option": "Solid solution strengthening", "choice_question": "下列哪个是强化金属材料的常见方法？", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening", "B": "Increasing elastic modulus", "C": "Reducing dislocation density", "D": "Enhancing surface reflectivity" }, "correct_answer": "A", "explanation": "Solid solution strengthening is a fundamental method where solute atoms distort the crystal lattice, impeding dislocation motion. Option B exploits cognitive bias by confusing stiffness (elastic modulus) with strength. Option C is a reverse intuition trap - while dislocations enable plasticity, reducing them would actually weaken most metals. Option D uses a completely unrelated material property to mislead.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3631, "question": "For \\mathrm{UO}_{2} with fluorite structure, determine the packing factor.", "answer": "The packing factor is pf = 0.624.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算UO2的堆积因子(packing factor)，需要通过数值计算和公式应用来得出具体数值0.624的答案。 | 知识层次: 题目要求计算UO2的堆积因子，这需要应用基本的几何公式和晶体结构知识，属于直接套用公式的简单计算题。虽然需要理解氟化钙结构的基本特征，但整体思维过程较为直接，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需要直接应用基本公式进行简单计算，属于单一公式直接计算的难度等级。学生只需知道氟化钙结构的堆积因子公式并代入数值即可得出答案，无需复杂的推理或多步骤计算。", "convertible": true, "correct_option": "0.624", "choice_question": "For \\mathrm{UO}_{2} with fluorite structure, the packing factor is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.624", "B": "0.740", "C": "0.680", "D": "0.520" }, "correct_answer": "A", "explanation": "The correct packing factor for UO2 with fluorite structure is 0.624, calculated based on the unit cell geometry and ion radii. Option B (0.740) is the packing factor for FCC/HCP structures, exploiting the common misconception that all ceramic structures have similar packing. Option C (0.680) mimics typical values for spinel structures, creating confusion through material system analogy. Option D (0.520) represents a distorted calculation that might result from incorrect ion radius assumptions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4902, "question": "For the Inconel and nickel pair that are coupled in seawater, predict the possibility of corrosion; if corrosion is probable, note which metal/alloy will corrode.", "answer": "For the Inconel-nickel couple, corrosion is unlikely inasmuch as both alloys appear within the same set of brackets (in both active and passive states).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求预测腐蚀可能性并解释哪种金属/合金会腐蚀，答案提供了文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求预测腐蚀可能性并解释原因，涉及对材料腐蚀行为的综合分析，需要理解不同金属在特定环境下的电化学行为及其相互作用。虽然不涉及复杂计算，但需要关联多个概念进行判断，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生对Inconel和镍在海水中的腐蚀行为有基本了解，并能根据它们在电偶序中的位置（同一组括号内）判断腐蚀可能性。这涉及中等应用层次的知识，包括多步计算、概念关联和综合分析，但不需要过于复杂的推导或深度关联性分析。", "convertible": true, "correct_option": "For the Inconel-nickel couple, corrosion is unlikely inasmuch as both alloys appear within the same set of brackets (in both active and passive states).", "choice_question": "For the Inconel and nickel pair that are coupled in seawater, predict the possibility of corrosion; if corrosion is probable, note which metal/alloy will corrode.", "conversion_reason": "The answer is a standard statement that can be directly used as a correct option in a multiple-choice question. The question can be presented as is, with the answer being one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Corrosion is unlikely as both alloys are in the same galvanic series bracket", "B": "Nickel will corrode due to its lower nobility compared to Inconel", "C": "Inconel will corrode preferentially due to its complex alloy composition", "D": "Severe galvanic corrosion will occur due to seawater electrolyte" }, "correct_answer": "A", "explanation": "The correct answer is A because Inconel and nickel fall within the same galvanic series bracket in both active and passive states, making significant corrosion unlikely. Option B exploits the common misconception about nobility differences within the same bracket. Option C traps those who overemphasize alloy complexity without considering galvanic series positioning. Option D exaggerates the electrolyte effect while ignoring the fundamental galvanic compatibility.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1535, "question": "Recrystallization annealing", "answer": "Recrystallization annealing: For plastically deformed metals, during the reheating process, when the temperature exceeds the recrystallization temperature, new grains with low defect density are formed, restoring properties such as strength to their pre-deformation levels, while the phase structure remains unchanged.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Recrystallization annealing\"进行文字解释和论述，答案提供了详细的定义和过程描述，符合简答题的特征。 | 知识层次: 题目考查对再结晶退火这一基本概念的记忆和理解，包括其定义、发生条件和效果，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（recrystallization annealing的定义和基本原理），但正确选项需要考生理解并描述一个相对完整的过程（包括温度条件、晶粒变化和性能恢复等），而不仅仅是简单的定义复述。这比单纯记忆定义（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Recrystallization annealing: For plastically deformed metals, during the reheating process, when the temperature exceeds the recrystallization temperature, new grains with low defect density are formed, restoring properties such as strength to their pre-deformation levels, while the phase structure remains unchanged.", "choice_question": "下列关于再结晶退火的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization annealing: For plastically deformed metals, during the reheating process, when the temperature exceeds the recrystallization temperature, new grains with low defect density are formed, restoring properties such as strength to their pre-deformation levels, while the phase structure remains unchanged.", "B": "Recrystallization annealing involves heating cold-worked metals above their melting point to eliminate dislocations and restore ductility, resulting in a complete phase transformation to austenite.", "C": "During recrystallization annealing, the primary mechanism is diffusion-controlled grain boundary migration, which always leads to a decrease in both strength and hardness compared to the cold-worked state.", "D": "Recrystallization annealing temperature is strictly defined as 0.4 times the absolute melting temperature of the material, regardless of prior deformation level or alloy composition." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes recrystallization annealing as a process where new defect-free grains form above the recrystallization temperature, restoring pre-deformation properties without phase change. Option B is incorrect because it confuses recrystallization with melting and introduces an erroneous phase transformation. Option C is a partial truth trap - while grain boundary migration occurs, the strength typically increases to pre-deformation levels, not decreases. Option D exploits the common approximation of recrystallization temperature but incorrectly presents it as an absolute rule ignoring material-specific factors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3758, "question": "A 5-cm diameter sphere solidifies in 1050s. Calculate the solidification time for a 0.3 cm × 10 cm × 20 cm plate cast under the same conditions. Assume that n=2.", "answer": "the solidification time for the plate is 31.15s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解固结时间，答案是一个具体的数值结果，解答过程需要运用材料科学中的相关公式和计算步骤。 | 知识层次: 题目需要进行多步计算，涉及固体凝固时间的公式应用和不同几何形状的转换，需要理解凝固时间与体积/表面积比的关系，并正确应用n=2的条件进行计算。虽然不涉及复杂的机理分析，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解凝固时间计算的基本概念（如Chvorinov法则），并能正确应用n=2的假设。题目涉及从球体到平板几何形状的转换计算，需要多步骤推导（包括等效模数计算和比例关系应用），但选择题型提供了正确选项，降低了部分计算验证的复杂度。", "convertible": true, "correct_option": "31.15s", "choice_question": "A 5-cm diameter sphere solidifies in 1050s. Under the same conditions, what is the solidification time for a 0.3 cm × 10 cm × 20 cm plate, assuming n=2?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "31.15s", "B": "1050s", "C": "8.82s", "D": "126.5s" }, "correct_answer": "A", "explanation": "The correct answer is A (31.15s) calculated using the Chvorinov's rule (t = k*(V/A)^n) with n=2. B (1050s) is a cognitive bias trap - using the sphere's time directly without considering geometry change. C (8.82s) is a unit conversion trap - incorrectly using thickness alone. D (126.5s) is a partial calculation trap - considering only two dimensions of the plate.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2431, "question": "Is the diffusion in oxide ceramics a vacancy exchange mechanism or a rotary exchange mechanism?", "answer": "The bonding in oxide ceramics is ionic bonding, and the diffusion mechanism in ionic crystals is primarily the vacancy exchange mechanism. The activation energy for the rotary exchange mechanism is too high and often disrupts the ionic bonding, so it cannot be the diffusion mechanism.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释扩散机制的类型，并提供详细的论述和理由，而不是从多个选项中选择或判断对错。答案也以文字解释的形式呈现，符合简答题的特征。 | 知识层次: 题目要求解释氧化物陶瓷中的扩散机制，涉及离子键合、空位交换机制和旋转交换机制的比较，需要综合运用材料科学中的扩散理论和晶体缺陷知识，进行推理分析和机理解释。这超出了简单记忆或基本应用的范围，属于复杂分析的层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解氧化物陶瓷中的扩散机制，还需要深入分析离子键合的特性，并比较空位交换机制和旋转交换机制的活化能差异。这需要综合运用材料科学中的键合理论、扩散机理和能量分析等多方面知识，进行复杂的推理和判断。正确选项的解释涉及机理深度解释和复杂现象全面分析，远超一般选择题的知识点掌握要求。", "convertible": true, "correct_option": "vacancy exchange mechanism", "choice_question": "What is the primary diffusion mechanism in oxide ceramics?", "conversion_reason": "The original short answer question asks about the diffusion mechanism in oxide ceramics, and the answer is a standard term ('vacancy exchange mechanism'). This can be converted into a multiple-choice question by providing options for different mechanisms.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Vacancy exchange mechanism", "B": "Interstitial diffusion mechanism", "C": "Rotary exchange mechanism", "D": "Direct exchange mechanism" }, "correct_answer": "A", "explanation": "The correct answer is A because oxide ceramics primarily diffuse through vacancy exchange due to their ionic bonding nature and stoichiometric constraints. Option B is a cognitive bias trap - while interstitial diffusion occurs in metals, it's rare in ceramics due to high energy barriers. Option C exploits professional intuition by suggesting a plausible-sounding but non-existent mechanism in ceramics. Option D is a multi-level verification trap - direct exchange occurs in some materials but requires unrealistic atomic movements in oxide ceramics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3165, "question": "The vacancy formation energy of copper is 1.7×10⁻¹⁹ J. Calculate the average vacancy concentration C at 1000°C, given the Boltzmann constant K=1.38×10⁻²³ J/K.", "answer": "The average vacancy concentration C = e^(-Ev/KT) = exp{- (1.7×10⁻¹⁹) / (1.38×10⁻²³ × 1273)} ≈ 6.27×10⁻⁵", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过具体计算得出的数值结果。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即使用Boltzmann公式计算空位浓度，不需要多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解并应用Boltzmann公式计算空位浓度，但题目已经提供了所有必要的参数和公式，解题步骤相对直接，仅需代入数值并进行简单计算即可得出结果。相较于需要多个公式组合或复杂分析的题目，此题的难度较低。", "convertible": true, "correct_option": "6.27×10⁻⁵", "choice_question": "The vacancy formation energy of copper is 1.7×10⁻¹⁹ J. Calculate the average vacancy concentration C at 1000°C, given the Boltzmann constant K=1.38×10⁻²³ J/K.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.27×10⁻⁵", "B": "1.25×10⁻⁴", "C": "3.14×10⁻⁵", "D": "2.51×10⁻⁴" }, "correct_answer": "A", "explanation": "正确答案A是通过正确的Arrhenius方程计算得出：C = exp(-E_v/kT)，其中E_v=1.7×10⁻¹⁹ J，T=1273K。干扰项B是忘记将温度转换为开尔文的结果；干扰项C是错误地将能量值减半的计算；干扰项D是错误地使用了摄氏温度而非开尔文温度的结果。这些干扰项利用了材料科学计算中常见的单位转换错误和公式应用错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4850, "question": "At temperatures between 540^{\\circ} C(813 K) and 727^{\\circ} C(1000 K), the activation energy and preexponential for the diffusion coefficient of \\mathrm{Na}^{+}in \\mathrm{NaCl} are 173,000 J/ mol and 4.0 × 10^{-4} m^{2} / s, respectively. Compute the mobility for an \\mathrm{Na}^{+}ion at 600^{\\circ} C(873 K).", "answer": "the mobility for a \\mathrm{na}^{+} ion at 600^{\\circ} C (873 k) is 2.34 × 10^{-13} m^{2}/\\mathrm{v}-s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的激活能和前置指数计算钠离子在特定温度下的迁移率，需要使用公式进行数值计算，答案也是一个具体的数值结果。 | 知识层次: 题目需要应用扩散系数的阿伦尼乌斯公式计算离子迁移率，涉及多步计算和概念关联，但不需要复杂的综合分析或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散系数与迁移率的关系，并应用阿伦尼乌斯公式进行多步计算。题目涉及温度转换、单位统一和公式推导，虽然选项已给出正确答案，但仍需较强的综合分析能力来验证。", "convertible": true, "correct_option": "2.34 × 10^{-13} m^{2}/\\mathrm{v}-s", "choice_question": "At temperatures between 540^{\\circ} C(813 K) and 727^{\\circ} C(1000 K), the activation energy and preexponential for the diffusion coefficient of \\mathrm{Na}^{+}in \\mathrm{NaCl} are 173,000 J/ mol and 4.0 × 10^{-4} m^{2} / s, respectively. Compute the mobility for an \\mathrm{Na}^{+}ion at 600^{\\circ} C(873 K).", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.34 × 10^{-13} m^{2}/V-s", "B": "3.72 × 10^{-12} m^{2}/V-s", "C": "1.56 × 10^{-14} m^{2}/V-s", "D": "4.81 × 10^{-11} m^{2}/V-s" }, "correct_answer": "A", "explanation": "正确答案A通过Nernst-Einstein关系式正确计算得出：u = (D * z * e)/(k * T)，其中D通过阿伦尼乌斯方程计算。干扰项B错误地将温度倒数项放在指数函数外；干扰项C错误使用了玻尔兹曼常数单位；干扰项D错误地将激活能量单位混淆为kJ/mol。这些干扰项利用了材料科学计算中常见的单位混淆和公式误用陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3166, "question": "To dissolve MgF2 into LiF, what type of vacancies should be introduced into LiF?", "answer": "Dissolving MgF2 into LiF, i.e., replacing Li+ with Mg2+, generates cation vacancies.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要解释和论述溶解MgF2到LiF中时应该引入的空位类型，答案以文字解释的形式给出，没有选项或计算要求。 | 知识层次: 题目需要理解溶解过程中离子替换的机制，并关联到空位的产生，涉及多步推理和概念关联，但不需要复杂的综合分析或创新应用。 | 难度: 在选择题中属于中等难度，需要理解离子替换的概念以及由此产生的空位类型。虽然题目涉及多个概念（离子替换、空位形成），但在选择题型中，正确选项直接给出了结论，减少了分析步骤的复杂性。考生需要具备将Mg2+替换Li+与阳离子空位形成关联起来的能力，这属于中等应用层次的知识要求。", "convertible": true, "correct_option": "Dissolving MgF2 into LiF, i.e., replacing Li+ with Mg2+, generates cation vacancies.", "choice_question": "To dissolve MgF2 into LiF, what type of vacancies should be introduced into LiF?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cation vacancies to maintain charge neutrality", "B": "Anion vacancies to compensate for the smaller Mg2+ ion", "C": "Schottky defects to balance both cation and anion sites", "D": "Frenkel defects to accommodate the size mismatch" }, "correct_answer": "A", "explanation": "The correct answer is A because substituting Li+ (1+) with Mg2+ (2+) creates a positive charge imbalance that must be compensated by cation vacancies. Option B is incorrect but tempting as it plays on the intuitive but wrong idea that smaller cations require anion vacancies. Option C exploits the common knowledge of Schottky defects in ionic crystals but misapplies it to this specific doping scenario. Option D leverages the valid concept of Frenkel defects but incorrectly applies it to a situation requiring charge compensation rather than size accommodation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 163, "question": "Among the following three substances, which one is most likely to form glass, and why? (1) Na2O·2SiO2; (2) Na2O·SiO2; (3) NaCl", "answer": "(1) Na2O·2SiO2 is most likely to form glass. Calculations show that R1=2.5, Y1=3. At high temperatures, (1) has high viscosity and is prone to form glass.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么某个物质最可能形成玻璃，需要文字解释和论述，而不是简单的选择或判断。答案中包含了理论依据（R1=2.5, Y1=3）和物理解释（高粘度易形成玻璃），符合简答题的特征。 | 知识层次: 题目要求考生不仅知道玻璃形成的条件，还需要通过计算R1和Y1值来比较不同物质的玻璃形成能力，涉及多步计算和概念关联。虽然不需要复杂的推理分析，但需要综合分析不同物质的组成和性质，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解玻璃形成的基本原理（如粘度、网络形成体与修饰体的比例关系），并能通过R1和Y1的计算结果进行综合分析。题目要求比较三种物质的玻璃形成倾向，涉及多步计算和概念关联，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "(1) Na2O·2SiO2", "choice_question": "Among the following three substances, which one is most likely to form glass?", "conversion_reason": "The original question asks to identify the most likely substance to form glass from given options, which can be directly converted to a multiple-choice format. The answer provides a clear correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Na2O·2SiO2 (soda-lime silicate composition)", "B": "Na2O·SiO2 (higher modifier content)", "C": "NaCl (ionic crystal with simple cubic structure)", "D": "SiO2 (pure silica with high melting point)" }, "correct_answer": "A", "explanation": "The correct answer is A because Na2O·2SiO2 represents the classic soda-lime silicate glass composition where the 2:1 SiO2:Na2O ratio creates optimal glass-forming ability by disrupting the silica network just enough to lower viscosity without causing crystallization. Option B is a cognitive bias trap - while Na2O·SiO2 contains glass-forming components, the higher modifier content actually reduces glass-forming tendency by oversaturating the network. Option C exploits material intuition - NaCl is an ionic crystal that cannot form glass under normal conditions. Option D is a multi-level verification trap - while pure SiO2 can form glass, it requires extremely high melting temperatures and rapid quenching compared to the soda-lime system, making it less likely under practical conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1286, "question": "The negative sign of the diffusion flux indicates that diffusion proceeds from high concentration to low concentration, and the driving force for diffusion in this process is (20)", "answer": "Chemical potential gradient (chemical force)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述扩散过程的驱动力，答案是一个概念性的解释（化学势梯度），而不是从多个选项中选择或进行数值计算。 | 知识层次: 题目考查扩散通量的负号含义以及扩散驱动力的基本概念，属于对基本原理的记忆和理解。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需考生记住扩散过程的驱动力是化学势梯度（化学力）这一基本定义。题目直接给出明确选项，无需复杂推理或概念比较，属于最简单的记忆性知识考查。", "convertible": true, "correct_option": "Chemical potential gradient (chemical force)", "choice_question": "The negative sign of the diffusion flux indicates that diffusion proceeds from high concentration to low concentration, and the driving force for diffusion in this process is:", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chemical potential gradient (chemical force)", "B": "Concentration gradient (Fick's first law)", "C": "Temperature gradient (thermal force)", "D": "Stress gradient (mechanical force)" }, "correct_answer": "A", "explanation": "The correct answer is A because the fundamental driving force for diffusion is the chemical potential gradient, not simply the concentration gradient. Option B is a strong distractor as Fick's first law uses concentration gradient, which is a common misconception. Option C exploits the thermal activation aspect of diffusion but is incorrect as the primary driving force. Option D targets confusion with stress-induced diffusion but is irrelevant here.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2174, "question": "What is cross-slip? What are the characteristics of its slip lines?", "answer": "Cross-slip refers to the simultaneous or alternating slip of two or more slip planes along a common slip direction. Their slip lines are usually zigzag or wavy. This is the result of screw dislocations repeatedly 'expanding' on different slip planes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"cross-slip\"进行定义并描述其滑移线特征，需要文字解释和论述，属于简答题类型。 | 知识层次: 题目考查对交叉滑移（cross-slip）这一基本概念的定义及其滑移线特征的理解和记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生不仅知道\"cross-slip\"的基本定义，还需要理解其特征（如zigzag或wavy slip lines）以及形成机制（screw dislocations在不同滑移面上的运动）。这超出了简单的定义记忆，需要对概念进行一定程度的解释和描述，但尚未达到需要阐述复杂概念体系的难度。", "convertible": true, "correct_option": "Cross-slip refers to the simultaneous or alternating slip of two or more slip planes along a common slip direction. Their slip lines are usually zigzag or wavy. This is the result of screw dislocations repeatedly 'expanding' on different slip planes.", "choice_question": "Which of the following best describes cross-slip and its characteristics?", "conversion_reason": "The answer is a standard definition and description of cross-slip, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cross-slip refers to the simultaneous or alternating slip of two or more slip planes along a common slip direction, resulting in zigzag or wavy slip lines due to screw dislocations moving between planes.", "B": "Cross-slip is the phenomenon where edge dislocations change their slip plane under stress, creating straight parallel slip lines on the material surface.", "C": "Cross-slip occurs when dislocations bypass obstacles by climbing out of their original slip plane, leading to curved slip traces on the surface.", "D": "Cross-slip describes the cooperative movement of multiple dislocations on the same slip plane, producing intersecting slip lines with sharp angles." }, "correct_answer": "A", "explanation": "The correct answer A precisely describes cross-slip involving screw dislocations moving between planes. Option B incorrectly attributes cross-slip to edge dislocations. Option C describes dislocation climb rather than cross-slip. Option D falsely suggests cross-slip occurs on a single plane. These distractors exploit common misconceptions about dislocation types and their movement mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3959, "question": "A cylindrical rod 380mm (15.0 in.) long and having a diameter of 10.0mm (0.40 in.), is to be subjected to a tensile load of 24,500 N (5500 lbf). Which of the four metals or alloys listed below will experience an elongation of no more than 0.9mm (0.035 in.) under this load? The materials are: Aluminum alloy (Modulus of Elasticity: 70 GPa), Brass alloy (Modulus of Elasticity: 100 GPa), Copper (Modulus of Elasticity: 110 GPa), Steel alloy (Modulus of Elasticity: 207 GPa).", "answer": "The materials that will experience an elongation of no more than 0.9mm under the load of 24,500 N are the Brass alloy, Copper, and Steel alloy, as their calculated elongations (0.57 mm, 0.52 mm, and 0.57 mm, respectively) are less than or equal to 0.9 mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算不同材料的伸长量来判断哪些材料满足伸长不超过0.9mm的条件。解答过程需要应用弹性模量和应力-应变关系的公式进行数值计算，最终得出具体数值结果。 | 知识层次: 题目需要进行多步计算（包括应力、应变和伸长量的计算），需要应用胡克定律公式，并综合分析不同材料的弹性模量对伸长量的影响。虽然计算过程相对直接，但涉及多个概念关联和综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解弹性模量的概念，进行多步计算（包括应力、应变和伸长量的计算），并对不同材料的结果进行比较分析。虽然题目提供了必要的参数，但解题过程涉及多个步骤和概念的综合应用。", "convertible": true, "correct_option": "Brass alloy, Copper, and Steel alloy", "choice_question": "A cylindrical rod 380mm (15.0 in.) long and having a diameter of 10.0mm (0.40 in.), is to be subjected to a tensile load of 24,500 N (5500 lbf). Which of the four metals or alloys listed below will experience an elongation of no more than 0.9mm (0.035 in.) under this load?", "conversion_reason": "The original question is a calculation problem with a definitive answer that can be presented as a multiple-choice question. The correct options are clearly identified based on the calculated elongations.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Aluminum alloy (Yield Strength: 275 MPa, Strain Hardening Exponent: 0.20)", "B": "Titanium alloy (Yield Strength: 830 MPa, Strain Hardening Exponent: 0.15)", "C": "Brass alloy (Yield Strength: 415 MPa, Strain Hardening Exponent: 0.35)", "D": "Steel alloy (Yield Strength: 450 MPa, Strain Hardening Exponent: 0.25)" }, "correct_answer": "D", "explanation": "正确答案D正确，因为钢合金的屈服强度与应变硬化指数的组合使其在给定载荷下变形最小。干扰项A利用了对铝合金高延展性的直觉判断；B利用了钛合金高强度但忽略了其低应变硬化指数的影响；C利用了黄铜合金中等强度但高应变硬化指数的特性制造迷惑。这些干扰项都针对AI模型可能过度依赖单一参数或产生错误关联的弱点设计。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 5, "correct_answers": 5, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 74, "question": "Explain the meaning of the symbol V_{Na}", "answer": "Sodium atom vacancy", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释符号V_{Na}的含义，需要文字解释和论述，答案\"Sodium atom vacancy\"是一个简短的文字解释，符合简答题的特征 | 知识层次: 题目考查对材料科学中缺陷符号的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目仅要求识别和记忆基础符号的定义（钠原子空位），属于最基本的概念记忆层次。不需要解释或分析，只需直接回忆符号对应的含义，因此属于最低难度等级。", "convertible": true, "correct_option": "Sodium atom vacancy", "choice_question": "What is the meaning of the symbol V_{Na}?", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by providing options including the correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Sodium atom vacancy", "B": "Vanadium-doped sodium compound", "C": "Voltage across sodium electrolyte", "D": "Vibrational mode of sodium lattice" }, "correct_answer": "A", "explanation": "The correct answer is A because V_{Na} is the standard notation in defect chemistry for a sodium vacancy. Option B exploits the 'V' symbol ambiguity by suggesting a doping interpretation. Option C leverages electrochemical intuition by misinterpreting 'V' as voltage. Option D targets phonon physics knowledge by incorrectly associating 'V' with vibrational modes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 750, "question": "In the ${\\\\bf R O}\\\\mathrm{-SiO}{2}$ system, the order of the size of the immiscibility regions for: (1) $\\\\mathbf{Mg0-SiO}{2}$; (2) $\\\\mathbf{CaO}\\\\mathbf{-SiO}{2}$; (3) $\\\\mathbf{SrO}\\\\mathbf{-SiO}{2}$; (4) BaO$\\\\mathrm{SiO}_{2}$ is (a)$\\\\left(1\\\\right)>\\\\left(2\\\\right)>\\\\left(3\\\\right)>\\\\left(4\\\\right)$(b)(4)>(3)>(2)>(1)(c)$\\\\left(2\\\\right)>\\\\left(1\\\\right)>\\\\left(3\\\\right)>\\\\left(4\\\\right)$ (d $)(3)>(4)>(2)>(1)$", "answer": "a", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从多个选项中选择正确的顺序排列，属于选择题类型 | 知识层次: 题目要求对不同氧化物-SiO2系统中的不混溶区大小进行排序，这需要理解离子半径对相图不混溶区的影响，并能够综合分析不同氧化物的特性（如离子半径变化趋势）来推断不混溶区的大小顺序。这属于中等应用层次，涉及多步分析和概念关联。 | 难度: 在选择题中属于较高难度，需要综合理解RO-SiO2系统中不同氧化物的不混溶区域大小规律，并掌握碱土金属离子半径对相分离的影响。题目要求考生将多个概念（离子半径效应、相图特征）进行关联分析，并正确排序四种系统的相对大小关系，解题步骤涉及多步逻辑判断和比较。虽然题目提供了选项引导，但正确解答需要较深入的材料科学知识背景和综合分析能力。", "convertible": true, "correct_option": "a", "choice_question": "In the ${\\bf R O}\\mathrm{-SiO}{2}$ system, the order of the size of the immiscibility regions for: (1) $\\mathbf{Mg0-SiO}{2}$; (2) $\\mathbf{CaO}\\mathbf{-SiO}{2}$; (3) $\\mathbf{SrO}\\mathbf{-SiO}{2}$; (4) BaO$\\mathrm{SiO}_{2}$ is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The immiscibility region size decreases with increasing cation size due to decreasing field strength", "B": "The immiscibility region size increases with cation size because larger cations promote phase separation", "C": "The immiscibility region shows no systematic trend with cation size as it depends primarily on temperature", "D": "The immiscibility region size first increases then decreases with cation size due to competing effects of polarizability and field strength" }, "correct_answer": "A", "explanation": "The correct answer is A because in RO-SiO2 systems, smaller cations (Mg2+) have higher field strength which enhances immiscibility. As cation size increases (Ca2+ → Sr2+ → Ba2+), the field strength decreases, reducing the immiscibility region. Option B is a common misconception that larger cations automatically increase phase separation. Option C exploits the AI's tendency to default to 'no clear trend' answers. Option D is a sophisticated trap combining partially correct concepts about polarizability but misapplying them to this system.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1442, "question": "For an edge dislocation line, what is the relationship between its climb direction and the Burgers vector?", "answer": "Perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释刃位错线的攀移方向与伯格斯矢量之间的关系，答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目考查对位错基本性质的理解，特别是刃位错的攀移方向与伯格斯矢量之间的关系，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即刃位错线的攀移方向与其柏氏矢量的关系。题目直接给出了正确选项\"Perpendicular\"，无需任何解释或分析步骤，属于最基础的定义简答级别。", "convertible": true, "correct_option": "Perpendicular", "choice_question": "For an edge dislocation line, what is the relationship between its climb direction and the Burgers vector?", "conversion_reason": "The answer is a standard term (Perpendicular) which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Perpendicular", "B": "Parallel", "C": "At 45 degrees", "D": "Depends on the slip plane orientation" }, "correct_answer": "A", "explanation": "The climb direction of an edge dislocation is always perpendicular to its Burgers vector because climb involves diffusion of vacancies/interstitials normal to the slip plane. Option B exploits the common misconception that motion directions should align with the Burgers vector. Option C uses an intermediate angle that seems plausible for mixed dislocations. Option D introduces a conditional element that appears sophisticated but is irrelevant for pure edge dislocations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 339, "question": "What are the main characteristics of martensitic transformation?", "answer": "Martensitic transformation is a diffusionless, shear-type phase transformation that occurs in both pure metals and alloys, and is controlled by interface processes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释马氏体转变的主要特征，答案提供了文字解释和论述，符合简答题的特点 | 知识层次: 题目考查马氏体相变的基本特征，属于定义和基本原理的记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然考查的是基础概念记忆，但需要考生理解并整合多个关键特征（扩散less、剪切型、界面过程控制等），比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Martensitic transformation is a diffusionless, shear-type phase transformation that occurs in both pure metals and alloys, and is controlled by interface processes.", "choice_question": "Which of the following best describes the main characteristics of martensitic transformation?", "conversion_reason": "The answer is a standard description of the concept, which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Martensitic transformation is a diffusionless, shear-type phase transformation that occurs in both pure metals and alloys, and is controlled by interface processes.", "B": "Martensitic transformation involves long-range atomic diffusion and results in equiaxed grain structures, similar to recrystallization processes.", "C": "The transformation occurs through nucleation and growth mechanisms with significant composition changes, following Fick's laws of diffusion.", "D": "Martensitic transformation is exclusively a bulk diffusion-controlled process that requires high temperature thermal activation." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the key features of martensitic transformation: it's diffusionless (no atomic rearrangement), shear-type (military transformation), occurs in various materials, and is interface-controlled. Option B incorrectly introduces diffusion and equiaxed structures (characteristic of recrystallization). Option C falsely attributes nucleation/growth mechanisms and composition changes. Option D wrongly claims it's bulk diffusion-controlled and requires high temperatures, which are characteristics of diffusional transformations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1986, "question": "Given the Burgers vector b=0.25 nm, if the misorientation angle θ of a symmetric tilt grain boundary is 10°, calculate the distance between dislocations at the grain boundary.", "answer": "When θ=10°, D=1.4 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的Burgers向量和错向角计算晶界位错间距，需要应用公式进行数值计算，答案是一个具体的数值结果。 | 知识层次: 题目需要应用基本公式（Burgers vector与位错间距的关系公式）进行简单计算，属于直接套用公式的范畴，不需要多步计算或综合分析。 | 难度: 在选择题型内，该题目仅需要直接应用单一公式（D = b/θ）进行计算，无需多个步骤或复杂推理。题目提供了所有必要参数，且计算过程简单直接，属于最基础的难度等级。", "convertible": true, "correct_option": "D=1.4 nm", "choice_question": "Given the Burgers vector b=0.25 nm, if the misorientation angle θ of a symmetric tilt grain boundary is 10°, what is the distance between dislocations at the grain boundary?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.4 nm", "B": "0.25 nm", "C": "2.5 nm", "D": "0.7 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (1.4 nm) calculated using D = b/θ (in radians). B (0.25 nm) is the Burgers vector itself, exploiting the tendency to confuse input parameters with solutions. C (2.5 nm) is 10 times the Burgers vector, playing on angle magnitude misinterpretation. D (0.7 nm) is half the correct answer, targeting those who might incorrectly halve the angle.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1513, "question": "For an edge dislocation line, the direction of its slip motion is (18) to the Burgers vector", "answer": "(18) parallel", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个单词（parallel）来回答问题，属于简答题的填空形式，需要根据知识理解来提供简短答案。 | 知识层次: 题目考查对位错滑移方向与伯格斯矢量关系的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目仅考察对位错滑移方向与伯格斯矢量关系的基础概念记忆，无需解释或分析，只需选择\"parallel\"这一简单定义性答案。这是材料科学中最基础的概念之一，在选择题中属于最基础难度层级。", "convertible": true, "correct_option": "parallel", "choice_question": "For an edge dislocation line, the direction of its slip motion is (18) to the Burgers vector", "conversion_reason": "The short answer question can be converted to a multiple-choice question as the answer is a standard term (parallel). The question can be presented as is, with the correct option being 'parallel'.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "parallel", "B": "perpendicular", "C": "at 45° angle", "D": "anti-parallel" }, "correct_answer": "A", "explanation": "The correct answer is A (parallel) because for an edge dislocation, the slip direction is always parallel to the Burgers vector. Option B (perpendicular) is a common misconception due to the perpendicular relationship between the Burgers vector and dislocation line. Option C (45° angle) exploits the visual similarity with mixed dislocations. Option D (anti-parallel) creates confusion with the opposite directionality of screw dislocations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 375, "question": "Up-hill diffusion", "answer": "Driven by the chemical potential gradient, solute diffuses from areas of low concentration to areas of high concentration.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对\"Up-hill diffusion\"现象进行文字解释和论述，答案是一个完整的句子解释该现象，符合简答题的特征。 | 知识层次: 题目涉及对化学势梯度驱动下溶质从低浓度向高浓度扩散的机理解释，需要综合运用扩散理论和热力学知识进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Driven by the chemical potential gradient, solute diffuses from areas of low concentration to areas of high concentration.", "choice_question": "Which of the following best describes up-hill diffusion?", "conversion_reason": "The answer is a standard description of the concept 'up-hill diffusion', which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Driven by the chemical potential gradient, solute diffuses from areas of low concentration to areas of high concentration", "B": "Occurs when temperature gradients overcome Fick's first law, causing reverse diffusion", "C": "A special case of interstitial diffusion where smaller atoms move against concentration gradients", "D": "Results from stress-induced lattice distortion creating preferential diffusion pathways" }, "correct_answer": "A", "explanation": "The correct answer describes the counterintuitive nature of up-hill diffusion where chemical potential (not concentration) gradient drives the process. Option B misapplies temperature effects on diffusion. Option C conflates interstitial mechanism with chemical potential driving force. Option D incorrectly attributes the phenomenon to mechanical stress rather than thermodynamic driving forces.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3745, "question": "Suppose that liquid nickel is undercooled until homogeneous nucleation occurs. Calculate the number of nickel atoms in the nucleus. Assume that the lattice parameter of the solid FCC nickel is 0.356 nm.", "answer": "the number of nickel atoms in the nucleus is 109 atoms.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算镍原子在核中的数量），并给出了具体的参数（FCC镍的晶格参数），答案也是一个具体的数值（109 atoms），符合计算题的特征。 | 知识层次: 题目需要应用均质形核理论，结合FCC晶体的晶格参数计算原子数，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解均匀成核、晶格参数、FCC结构等概念，并进行多步计算（如计算晶胞体积、原子数等）。虽然题目提供了正确选项，但解题过程涉及多个知识点的综合应用和计算步骤，对学生的理解能力和计算能力有一定要求。", "convertible": true, "correct_option": "109 atoms", "choice_question": "Suppose that liquid nickel is undercooled until homogeneous nucleation occurs. The number of nickel atoms in the nucleus is: (Assume that the lattice parameter of the solid FCC nickel is 0.356 nm.)", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "109 atoms", "B": "128 atoms (FCC unit cell atoms × 4 unit cells)", "C": "74 atoms (assuming BCC structure by mistake)", "D": "92 atoms (incorrect volume calculation)" }, "correct_answer": "A", "explanation": "The correct answer is A (109 atoms) because it properly accounts for the critical nucleus size in homogeneous nucleation of FCC nickel. Option B is a cognitive bias trap - while 4 FCC unit cells do contain 128 atoms, this incorrectly assumes the nucleus forms perfect cubic units. Option C exploits structural confusion by using BCC atom count. Option D presents a plausible but incorrectly calculated volume-based estimate that advanced AIs might generate if they make rounding errors in spherical volume calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 609, "question": "At room temperature, the equilibrium microstructure of hypoeutectoid steel is", "answer": "ferrite and pearlite", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求描述亚共析钢在室温下的平衡显微组织，答案需要给出具体的组织名称（铁素体和珠光体），属于需要文字解释和论述的简答题类型 | 知识层次: 题目考查对亚共析钢在室温下平衡显微组织的基础概念记忆，仅需回答铁素体和珠光体这一基本知识点，无需深入分析或综合应用。 | 难度: 该题目属于基础概念记忆类型，仅需回忆亚共析钢在室温下的平衡显微组织（铁素体和珠光体）这一基本定义即可作答，无需复杂分析或概念关联。在选择题型中属于最基础的难度等级。", "convertible": true, "correct_option": "ferrite and pearlite", "choice_question": "At room temperature, the equilibrium microstructure of hypoeutectoid steel is:", "conversion_reason": "The answer is a standard term in materials science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ferrite and pearlite", "B": "austenite and cementite", "C": "ferrite and cementite", "D": "pearlite and cementite" }, "correct_answer": "A", "explanation": "The correct answer is A because hypoeutectoid steel at room temperature consists of ferrite (formed from proeutectoid ferrite) and pearlite (a lamellar structure of ferrite and cementite). Option B is incorrect because austenite is not stable at room temperature. Option C is a trap for those who forget pearlite is the equilibrium structure, not separate ferrite and cementite. Option D misses the proeutectoid ferrite phase present in hypoeutectoid steels.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4244, "question": "Briefly explain the concept of steady state as it applies to diffusion.", "answer": "Steady-state diffusion is the situation wherein the rate of diffusion into a given system is just equal to the rate of diffusion out, such that there is no net accumulation or depletion of diffusing species--i.e., the diffusion flux is independent of time.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要解释稳态扩散的概念，答案以文字解释和论述的形式呈现，没有涉及计算、选择或判断对错。 | 知识层次: 题目考查对稳态扩散这一基本概念的记忆和理解，不需要复杂的应用或分析，仅需解释其定义和基本原理。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释稳态扩散的概念，但正确选项已经提供了清晰的定义和关键特征（如扩散速率相等、无净积累、通量不随时间变化等）。这需要考生不仅记住定义，还要理解其背后的基本原理，但不需要进行复杂的分析或比较多个概念。因此，它属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "Steady-state diffusion is the situation wherein the rate of diffusion into a given system is just equal to the rate of diffusion out, such that there is no net accumulation or depletion of diffusing species--i.e., the diffusion flux is independent of time.", "choice_question": "Which of the following best describes the concept of steady state as it applies to diffusion?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Steady-state diffusion occurs when the concentration gradient remains constant over time, resulting in a time-independent diffusion flux", "B": "Steady-state diffusion is achieved when the diffusion coefficient becomes independent of temperature according to Arrhenius equation", "C": "Steady-state diffusion refers to the condition where the diffusing species completely saturate the host material, stopping further diffusion", "D": "Steady-state diffusion describes the situation where Fick's first law transforms into Fick's second law through mathematical derivation" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the time-independent nature of steady-state diffusion where the concentration profile doesn't change with time. Option B incorrectly associates steady-state with temperature dependence of diffusion coefficient. Option C confuses steady-state with saturation limit, a common misconception. Option D misrepresents the relationship between Fick's laws, where the second law is actually derived from the first law under non-steady-state conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3280, "question": "What is the inherent grain size of austenite?", "answer": "According to the former national metallurgical industry standard, the grain size measured after heating the steel to 930°C ± 10°C, holding for 8 hours, and then cooling is called the inherent grain size. This grain size is used to indicate the tendency of austenite grain growth during heating.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"inherent grain size of austenite\"进行解释说明，答案提供了详细的定义和测量方法，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对固有晶粒尺寸这一基本概念的记忆和理解，涉及标准测试方法和定义，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然题目涉及具体的温度和时间参数（930°C ± 10°C，8小时），但核心是考察对\"固有晶粒度\"这一基础概念的定义记忆。正确选项直接给出了标准定义和测试方法，不需要进行比较分析或推导。属于概念解释和描述层级，但相比纯定义记忆题（等级1）需要掌握更多细节参数。", "convertible": true, "correct_option": "According to the former national metallurgical industry standard, the grain size measured after heating the steel to 930°C ± 10°C, holding for 8 hours, and then cooling is called the inherent grain size. This grain size is used to indicate the tendency of austenite grain growth during heating.", "choice_question": "What is the inherent grain size of austenite?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The grain size measured after heating to 930°C ± 10°C for 8 hours followed by cooling", "B": "The initial grain size observed immediately after austenitization at Ac3 temperature", "C": "The minimum achievable grain size through severe plastic deformation", "D": "The grain size stabilized by Zener pinning at 0.8Tm of the material" }, "correct_answer": "A", "explanation": "Correct answer A follows the standard metallurgical definition of inherent grain size. Option B exploits the common misconception that inherent grain size relates to initial formation conditions. Option C leverages confusion with ultra-fine grain processing techniques. Option D uses a plausible but incorrect thermodynamic stabilization concept, playing on the AI's tendency to over-apply theoretical models.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2825, "question": "An aluminum rod with a length of 20m and a diameter of 14mm is drawn through a die with an aperture of 12.7mm. Calculate the length of the aluminum rod after drawing.", "answer": "During the deformation process, the total volume remains unchanged. Let the length after drawing be L, then π(14.0/2)^2×20×10^3 = π(12.7/2)^2×L×10^3, L=24.3m", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铝棒在拉伸后的长度，答案也是通过具体的计算步骤得出的数值结果。 | 知识层次: 题目主要考查基本公式的应用和简单计算，涉及体积不变原理的直接套用，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用体积不变原理这一基本公式进行计算，解题步骤简单，无需组合多个公式或进行复杂分析。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "24.3m", "choice_question": "An aluminum rod with a length of 20m and a diameter of 14mm is drawn through a die with an aperture of 12.7mm. What is the length of the aluminum rod after drawing?", "conversion_reason": "The calculation question has a definite numerical answer, making it suitable for conversion into a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "24.3m", "B": "22.1m", "C": "17.6m", "D": "20.0m" }, "correct_answer": "A", "explanation": "The correct answer is A (24.3m) based on volume conservation principle in metal forming (πr₁²L₁ = πr₂²L₂). Option B (22.1m) is designed to exploit cognitive bias by using an incorrect area ratio calculation. Option C (17.6m) traps those who confuse drawing with extrusion processes. Option D (20.0m) targets those who assume length remains constant, ignoring plastic deformation fundamentals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3002, "question": "The five major engineering plastics are (1), (2), (3), (4), (5).", "answer": "(1)Polyoxymethylene; (2)Polyamide; (3)Polycarbonate; (4)ABS; (5)Polysulfone", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写五个主要工程塑料的名称，需要学生回忆并列举具体材料名称，属于简答题类型。答案形式为文字列举，而非选择或判断。 | 知识层次: 题目考查对五大工程塑料名称的记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需回忆五大工程塑料的具体名称，无需解释或分析。题目要求的知识点掌握深度较浅，解题步骤简单直接，属于选择题型中最基础的难度等级。", "convertible": true, "correct_option": "Polyoxymethylene; Polyamide; Polycarbonate; ABS; Polysulfone", "choice_question": "下列哪一组材料属于五大工程塑料？", "conversion_reason": "原题目是简答题，要求列举五大工程塑料。答案为标准术语，可以转换为单选题形式，通过选项列举可能的组合，其中一组为正确答案。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polyoxymethylene; Polyamide; Polycarbonate; ABS; Polysulfone", "B": "Polyethylene; Polypropylene; Polystyrene; PVC; PET", "C": "Polyimide; PTFE; PEEK; LCP; PPS", "D": "Polyurethane; Phenolic resin; Epoxy; Unsaturated polyester; Silicone" }, "correct_answer": "A", "explanation": "正确答案A是国际公认的五大工程塑料。B选项是五大通用塑料，利用认知偏差让AI混淆工程塑料与通用塑料。C选项是高性能工程塑料，利用专业直觉陷阱让AI选择更'高级'的材料。D选项是热固性塑料，设计多层次验证陷阱让AI忽略工程塑料必须是热塑性的关键约束。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3092, "question": "What is the reinforcement mechanism of fiber-reinforced composites?", "answer": "Fiber-reinforced composites are formed by combining high-strength, high-modulus continuous (long) fibers or discontinuous (short) fibers with a matrix (resin, metal, ceramic, etc.). When the composite material is subjected to force, the high-strength, high-modulus reinforcing fibers bear most of the load, while the matrix primarily acts as a medium to transfer and disperse the load.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释纤维增强复合材料的增强机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查纤维增强复合材料的基本增强机制，属于基本原理的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并描述纤维增强复合材料的增强机制，包括纤维和基体的作用。这比简单的定义记忆（等级1）要求更高，但不需要复杂的分析或比较（等级3）。", "convertible": true, "correct_option": "Fiber-reinforced composites are formed by combining high-strength, high-modulus continuous (long) fibers or discontinuous (short) fibers with a matrix (resin, metal, ceramic, etc.). When the composite material is subjected to force, the high-strength, high-modulus reinforcing fibers bear most of the load, while the matrix primarily acts as a medium to transfer and disperse the load.", "choice_question": "Which of the following best describes the reinforcement mechanism of fiber-reinforced composites?", "conversion_reason": "The answer is a standard explanation of the reinforcement mechanism, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The high-strength fibers primarily bear the load while the matrix transfers stress, with interfacial bonding ensuring load transfer efficiency", "B": "The matrix material develops crystalline structures around fibers that enhance overall stiffness through phase transformation", "C": "Fiber-matrix thermal expansion mismatch creates compressive stresses that improve fracture toughness", "D": "Fiber alignment induces anisotropic electron cloud polarization that reinforces covalent bonding" }, "correct_answer": "A", "explanation": "The correct answer A describes the fundamental reinforcement mechanism where fibers carry most of the load while the matrix transfers stress. Option B incorrectly suggests crystalline phase transformation, which doesn't occur in typical polymer matrices. Option C describes a secondary effect (residual stresses) rather than the primary reinforcement mechanism. Option D introduces an entirely fictional quantum mechanical concept that doesn't apply to macroscopic composite behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3403, "question": "Why do the dimensions of some measuring tools change during storage and use?", "answer": "The reason for the dimensional changes of measuring tools during storage and use is: due to the excessive amount of retained austenite after quenching and tempering, stress relaxation occurs during storage and use, causing the retained austenite to transform, thereby leading to dimensional changes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么测量工具的尺寸在储存和使用过程中会发生变化，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目需要解释测量工具尺寸变化的机理，涉及淬火回火后残余奥氏体的应力松弛和相变过程，需要综合运用材料科学知识进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅要理解淬火回火后残余奥氏体的概念，还需要掌握应力松弛和相变机理对尺寸变化的影响机制。解题需要综合运用材料热处理、相变动力学和尺寸稳定性等多方面知识，进行复杂的机理分析和推理判断。这种深度机理解释和复杂现象分析的题目，在选择题型中属于对专业知识和分析能力要求最高的类型。", "convertible": true, "correct_option": "due to the excessive amount of retained austenite after quenching and tempering, stress relaxation occurs during storage and use, causing the retained austenite to transform, thereby leading to dimensional changes", "choice_question": "Why do the dimensions of some measuring tools change during storage and use?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "due to the excessive amount of retained austenite after quenching and tempering, stress relaxation occurs during storage and use, causing the retained austenite to transform, thereby leading to dimensional changes", "B": "because of creep deformation caused by residual stresses from the manufacturing process under ambient temperature conditions", "C": "as a result of reversible martensitic transformation triggered by minor temperature fluctuations during storage", "D": "due to oxidation-induced surface layer expansion that creates compressive stresses in the bulk material" }, "correct_answer": "A", "explanation": "The correct answer is A because retained austenite transformation is the primary mechanism for dimensional instability in precision measuring tools. Option B exploits the common misconception that creep occurs at room temperature, while in reality it requires elevated temperatures for most metals. Option C uses the martensitic transformation concept correctly but falsely suggests it's reversible in this context. Option D creates a plausible-sounding surface phenomenon that doesn't actually account for bulk dimensional changes in precision tools.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1070, "question": "Assuming carbon atoms are all located in the octahedral interstices of γ-Fe, calculate the maximum proportion of octahedral interstices occupied by carbon atoms in γ-Fe. (The atomic weight of iron is 55.85, and the Avogadro constant is 0.602×10^24)", "answer": "In the γ-Fe phase, the maximum carbon concentration C_max = 2.11%. Given that γ-Fe has an FCC structure with n = 4, there are 400 Fe atoms per 100 unit cells. The mass fraction of Fe is: w_Fe = 1 - 2.11% = 97.89%. The total mass is: M = (400 × 55.85) / 0.9789 = 22821.5. The number of carbon atoms is: n_c = (M × C_max) / M_c = (22821.5 × 0.0211) / 12 = 40. Thus, there are 40 carbon atoms per 100 unit cells.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，以确定γ-Fe中碳原子占据八面体间隙的最大比例。答案中包含了具体的计算步骤和数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括质量分数的转换、总质量的计算以及碳原子数量的确定。虽然涉及的是基本的公式应用，但需要综合运用多个概念和步骤来解决问题，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解γ-Fe的FCC结构、碳原子占据八面体间隙的概念，并进行多步计算（包括质量分数计算、总质量计算和碳原子数量计算）。虽然题目提供了部分数据，但仍需要综合应用材料科学和化学知识来解决问题。", "convertible": true, "correct_option": "40 carbon atoms per 100 unit cells", "choice_question": "Assuming carbon atoms are all located in the octahedral interstices of γ-Fe, what is the maximum proportion of octahedral interstices occupied by carbon atoms in γ-Fe? (The atomic weight of iron is 55.85, and the Avogadro constant is 0.602×10^24)", "conversion_reason": "The answer is a specific numerical value derived from the calculation, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "40 carbon atoms per 100 unit cells", "B": "50 carbon atoms per 100 unit cells", "C": "1 carbon atom per unit cell", "D": "4 carbon atoms per unit cell" }, "correct_answer": "A", "explanation": "The correct answer is A because γ-Fe has an FCC structure with 4 octahedral interstices per unit cell, but due to size constraints and repulsion between carbon atoms, only 40% can be occupied (40 per 100 cells). Option B is a cognitive bias trap suggesting perfect 50% occupation. Option C exploits the common mistake of assuming one interstitial per cell. Option D is a professional intuition trap suggesting all interstices can be filled simultaneously.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3163, "question": "Calculate the number of atoms N in 1 cm³ of copper, given that the density of copper is 8.9 g/cm³, the relative atomic mass is 63.5, and Avogadro's number is 6.02×10²³.", "answer": "N = (6.02×10²³ × 8.9) / 63.5 ≈ 0.84×10²³", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及密度、相对原子质量和阿伏伽德罗常数的计算，最终得出具体的数值结果。 | 知识层次: 题目需要应用基本的公式（密度、摩尔质量、阿伏伽德罗常数）进行简单计算，属于直接套用公式的范畴，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（N = (Avogadro's number × density) / relative atomic mass）并进行简单计算，无需组合多个公式或进行复杂分析。题目提供的所有必要参数明确，计算步骤直接，属于最基础的单一公式应用层级。", "convertible": true, "correct_option": "0.84×10²³", "choice_question": "Calculate the number of atoms N in 1 cm³ of copper, given that the density of copper is 8.9 g/cm³, the relative atomic mass is 63.5, and Avogadro's number is 6.02×10²³. The correct answer is:", "conversion_reason": "The calculation problem has a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.84×10²³", "B": "8.4×10²²", "C": "1.06×10²³", "D": "5.3×10²²" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算得出的：N = (密度×体积×阿伏伽德罗常数)/相对原子质量 = (8.9×1×6.02×10²³)/63.5 ≈ 0.84×10²³。干扰项B通过错误地移动小数点位置制造视觉混淆；干扰项C是忽略密度直接使用原子质量倒数计算的结果；干扰项D则是错误地将计算结果除以2，模拟常见计算错误。这些干扰项都利用了材料科学计算中常见的认知偏差和直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1968, "question": "Please write out the crystal planes included in the {110} and {100} crystal plane families in the cubic crystal system, respectively.", "answer": "{110}: (110) (101) (011) (110) (101) (011) {100}: (100) (010) (001) (001) (010) (100)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求写出立方晶系中{110}和{100}晶面族包含的所有晶面，需要列举具体的晶面指数，属于需要文字回答的简答题类型。答案形式为列举具体晶面而非计算或选择。 | 知识层次: 题目考查立方晶系中{110}和{100}晶面族包含的具体晶面的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确回忆并区分立方晶系中{110}和{100}晶面族包含的具体晶面。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。考生需要理解晶面族的对称性并正确列举所有等效晶面，这属于概念解释和描述的范畴。", "convertible": true, "correct_option": "{110}: (110) (101) (011) (110) (101) (011) {100}: (100) (010) (001) (001) (010) (100)", "choice_question": "Which of the following correctly lists the crystal planes included in the {110} and {100} crystal plane families in the cubic crystal system?", "conversion_reason": "The answer is a standard and specific list of crystal planes, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "{110}: (110) (101) (011) (110) (101) (011) {100}: (100) (010) (001) (001) (010) (100)", "B": "{110}: (110) (101) (011) (110) (101) (011) {100}: (100) (010) (001)", "C": "{110}: (110) (101) (011) {100}: (100) (010) (001)", "D": "{110}: (110) (101) (011) (110) (101) (011) (110) (101) (011) {100}: (100) (010) (001) (001) (010) (100)" }, "correct_answer": "A", "explanation": "正确答案A完整列出了立方晶系中{110}和{100}晶面族的所有等效晶面。选项B错误地遗漏了{100}晶面族的负指数晶面，利用了'第一印象'正确但深入分析错误的认知偏差。选项C仅列出部分等效晶面，属于专业直觉陷阱。选项D重复列出{110}晶面族的晶面，是多层次验证陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1366, "question": "At what temperature or temperature range is primary cementite formed, and through what reaction? Also, write the reaction equation.", "answer": "Primary cementite: >1148°C, eutectic reaction, L→Fe3C1.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释温度范围、反应类型并写出反应方程式，需要文字解释和论述，符合简答题的特征 | 知识层次: 题目考查对初级渗碳体形成温度范围、反应类型及反应方程的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生准确掌握初级渗碳体的形成温度范围（>1148°C）和共晶反应（L→Fe3C1）这两个关键知识点。这比单纯记忆定义（等级1）要求更高，但又不涉及复杂概念体系的阐述（等级3）。", "convertible": true, "correct_option": ">1148°C, eutectic reaction, L→Fe3C1", "choice_question": "At what temperature or temperature range is primary cementite formed, and through what reaction?", "conversion_reason": "The answer is a specific temperature range and reaction, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": ">1148°C, eutectic reaction: L→Fe3C1", "B": "727-1148°C, eutectoid reaction: γ→Fe3C1 + α", "C": "<727°C, precipitation reaction: α→Fe3C1", "D": "1495°C, peritectic reaction: L + δ→Fe3C1" }, "correct_answer": "A", "explanation": "Primary cementite forms above 1148°C through the eutectic reaction in hypereutectic cast irons. Option B describes the pearlite formation, a common confusion point. Option C mimics tempering processes, exploiting precipitation reaction similarity. Option D uses a real peritectic temperature but wrong reaction type, targeting memory of phase diagram points.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4692, "question": "(b) Repeat this calculation at room temperature (298 K). Assume an energy for vacancy formation of 0.90 eV/atom.", "answer": "the fraction of atom sites that are vacant for copper at 298 k is 6.08 × 10^-16.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算空位分数），并给出了具体的计算条件和参数（温度298 K，空位形成能0.90 eV/atom）。答案是一个具体的数值结果（6.08 × 10^-16），这表明解答过程涉及公式应用和数值计算。 | 知识层次: 题目要求使用给定的能量值和温度进行简单的数值计算，直接套用公式计算空位分数，属于基本公式应用和简单计算，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算，属于最基础的难度等级。题目明确给出了所有必要参数（温度、空位形成能），只需将数值代入公式即可得出答案，无需额外的分析或组合多个公式。", "convertible": true, "correct_option": "6.08 × 10^-16", "choice_question": "At room temperature (298 K), assuming an energy for vacancy formation of 0.90 eV/atom, the fraction of atom sites that are vacant for copper is:", "conversion_reason": "The calculation question has a specific numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.08 × 10^-16", "B": "3.04 × 10^-16", "C": "1.22 × 10^-15", "D": "2.43 × 10^-8" }, "correct_answer": "A", "explanation": "正确答案A是通过正确的Boltzmann分布计算得出的空位分数。干扰项B利用了常见的一半错误直觉，干扰项C是温度加倍时的计算结果，干扰项D则错误使用了晶格振动频率而非空位形成能。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 802, "question": "What is the physical significance of the critical nucleus?", "answer": "The physical significance of the critical nucleus: the smallest embryo that can grow spontaneously (or, a nucleus with a radius equal to rk).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释临界核的物理意义，答案提供了文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查对临界晶核物理意义的基本概念记忆和理解，属于定义性知识 | 难度: 在选择题型中，该题目仅考察对\"critical nucleus\"基本定义的记忆，属于最基础的概念性知识。正确选项直接给出了定义表述，不需要任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "the smallest embryo that can grow spontaneously (or, a nucleus with a radius equal to rk)", "choice_question": "What is the physical significance of the critical nucleus?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The smallest embryo that can grow spontaneously", "B": "The nucleus size where surface energy equals bulk energy", "C": "The point where nucleation rate reaches maximum", "D": "The radius at which Gibbs free energy change is zero" }, "correct_answer": "A", "explanation": "The correct answer is A because the critical nucleus is defined as the smallest stable cluster of atoms that can grow without requiring additional energy input. Option B is a cognitive bias trap - while surface and bulk energies are equal at critical size, this is not the defining characteristic. Option C exploits professional intuition by confusing thermodynamic stability with kinetic behavior. Option D is a multi-level verification trap - while ΔG reaches a maximum at critical size, it's never zero in this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 514, "question": "Stored energy", "answer": "Stored energy: A small portion of the energy consumed during cold deformation exists within the deformed crystal in the form of elastic strain energy and structural defect energy, which is called stored energy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Stored energy\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查的是对\"stored energy\"这一基本概念的定义和解释，属于材料科学中基础概念的记忆和理解范畴，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目仅要求记忆和识别\"stored energy\"的基本定义，属于最基础的概念记忆层次。题目直接给出了定义性描述，不需要进行概念解释或复杂分析，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "A small portion of the energy consumed during cold deformation exists within the deformed crystal in the form of elastic strain energy and structural defect energy, which is called stored energy.", "choice_question": "Which of the following best describes stored energy?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A small portion of the energy consumed during cold deformation exists within the deformed crystal in the form of elastic strain energy and structural defect energy", "B": "The total potential energy difference between the deformed and annealed states of a material", "C": "The energy required to initiate recrystallization in a cold-worked metal", "D": "The excess free energy stored primarily as vacancies and dislocations after plastic deformation" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines stored energy as the portion of deformation energy retained in the crystal structure. Option B is a cognitive bias trap, overgeneralizing the concept to include all potential energy differences. Option C exploits professional intuition by focusing on recrystallization threshold rather than stored energy itself. Option D is a multi-level verification trap, containing partially correct elements (dislocations) but incorrectly emphasizing vacancies which are minor contributors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3596, "question": "Bismuth has a hexagonal structure, with a0=0.4546 nm and c0=1.186 nm. The density is 9.808 g/cm3 and the atomic weight is 208.98 g/mol. Determine the volume of the unit cell.", "answer": "0.21226 nm3 or 2.1226 x 10^-22 cm3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定单位晶胞的体积，答案是一个具体的数值结果，解答过程需要运用密度、原子量和晶格参数等数据进行计算。 | 知识层次: 题目要求应用基本的晶体学公式计算单位晶胞体积，涉及简单的数值计算和单位转换，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算单位晶胞的体积，只需要应用六方晶系的体积公式V = (3√3/2) * a0² * c0，代入给定的a0和c0值即可得到结果。不需要额外的概念理解或多步骤计算，属于最基础的计算题类型。", "convertible": true, "correct_option": "0.21226 nm3 or 2.1226 x 10^-22 cm3", "choice_question": "Bismuth has a hexagonal structure, with a0=0.4546 nm and c0=1.186 nm. The density is 9.808 g/cm3 and the atomic weight is 208.98 g/mol. What is the volume of the unit cell?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.21226 nm³", "B": "0.4546 nm³", "C": "1.186 nm³", "D": "0.10613 nm³" }, "correct_answer": "A", "explanation": "The correct answer is A (0.21226 nm³) calculated using the formula for hexagonal unit cell volume: V = (√3/2) × a0² × c0. Option B (0.4546 nm³) is a cognitive bias trap using just the a0 parameter. Option C (1.186 nm³) exploits unit confusion by presenting the c0 value alone. Option D (0.10613 nm³) is a half-volume trap designed to catch those who might divide by 2 incorrectly when considering atomic packing factor.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1599, "question": "What is the difference in deformation mode between slip and twinning, the two mechanisms of metal plastic deformation?", "answer": "The slip process involves the relative sliding of one part of the crystal relative to another, while the twinning process involves the uniform shear of one part of the crystal relative to another.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两种金属塑性变形机制的区别，答案需要文字解释和论述，没有提供选项或要求进行判断或计算。 | 知识层次: 题目考查金属塑性变形中滑移和孪生两种机制的基本概念和区别，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（滑移和孪生的定义），但需要考生理解并区分两种塑性变形机制的具体差异（相对滑动 vs 均匀剪切）。这比单纯记忆单个定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。正确选项通过对比方式清晰解释了两种机制的关键区别，符合选择题型中对概念解释和描述的要求。", "convertible": true, "correct_option": "The slip process involves the relative sliding of one part of the crystal relative to another, while the twinning process involves the uniform shear of one part of the crystal relative to another.", "choice_question": "What is the difference in deformation mode between slip and twinning, the two mechanisms of metal plastic deformation?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip occurs through dislocation motion while twinning involves coordinated atomic shuffling without dislocations", "B": "Both mechanisms involve dislocation motion but twinning requires specific crystallographic orientations", "C": "Slip preserves the crystal structure while twinning creates a mirror-image lattice orientation", "D": "Twinning requires higher stress than slip because it involves breaking more atomic bonds simultaneously" }, "correct_answer": "C", "explanation": "Correct answer C captures the fundamental difference that slip preserves the original crystal orientation while twinning creates a mirrored orientation. Option A is incorrect because twinning does not involve 'atomic shuffling'. Option B is wrong as twinning does not require dislocations. Option D is a common misconception - while twinning often requires higher stress, this is not due to bond breaking but rather the coordinated nature of the deformation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4495, "question": "Explain briefly why the tendency of a polymer to crystallize decreases with increasing molecular weight.", "answer": "The tendency of a polymer to crystallize decreases with increasing molecular weight because as the chains become longer it is more difficult for all regions along adjacent chains to align so as to produce the ordered atomic array.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释聚合物结晶倾向随分子量增加而降低的原因，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释高分子结晶倾向随分子量增加而降低的机理，需要深入理解高分子链排列和结晶过程的复杂性，涉及分子链长度对有序排列的影响机制，属于对材料科学原理的综合分析和推理解释。 | 难度: 在选择题型中，该题目属于较高难度等级。虽然题目形式为选择题，但正确选项要求考生理解高分子结晶的机理，并能分析分子量增加对结晶倾向的影响。这需要考生掌握高分子链排列的微观机制，并能将分子链长度与结晶难易度建立因果关系。相比简单记忆型或基础概念型选择题，此类题目要求考生具备机理深度解释能力，属于选择题型中较难的类型。", "convertible": true, "correct_option": "The tendency of a polymer to crystallize decreases with increasing molecular weight because as the chains become longer it is more difficult for all regions along adjacent chains to align so as to produce the ordered atomic array.", "choice_question": "Why does the tendency of a polymer to crystallize decrease with increasing molecular weight?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Longer polymer chains have higher entanglement density which kinetically hinders chain alignment", "B": "Increased molecular weight reduces the glass transition temperature, making crystallization thermodynamically unfavorable", "C": "Higher molecular weight polymers have stronger intermolecular forces that prevent ordered packing", "D": "The end-group concentration decreases with molecular weight, reducing nucleation sites for crystallization" }, "correct_answer": "A", "explanation": "The correct answer is A because longer polymer chains indeed have more entanglements that physically prevent the extensive chain alignment required for crystallization. Option B is a thermodynamic trap - while Tg may change slightly, it doesn't directly explain the crystallization tendency. Option C reverses the logic - stronger forces would actually promote crystallization. Option D sounds plausible but end-group effects become negligible at typical molecular weights for crystallization studies.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 538, "question": "7. Small-angle grain boundaries are composed of dislocations, among which symmetric tilt boundaries are composed of (14) dislocations, and twist boundaries are composed of (15) dislocations.", "answer": "(14) edge; (15) screw", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写特定类型的位错名称（刃型位错和螺型位错），属于需要准确回答特定术语的简答题形式。虽然形式上类似填空题，但根据提供的题型选项，最接近的是简答题类型。 | 知识层次: 题目考查对小角度晶界和位错类型的基本概念的记忆和理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目直接考察对对称倾斜晶界和扭转晶界组成位错类型的基础记忆，无需复杂推理或概念比较。正确选项直接对应基础概念记忆，属于最基础的选择题难度。", "convertible": true, "correct_option": "edge; screw", "choice_question": "Small-angle grain boundaries are composed of dislocations, among which symmetric tilt boundaries are composed of (14) dislocations, and twist boundaries are composed of (15) dislocations. Which of the following correctly fills in the blanks (14) and (15)?", "conversion_reason": "The original short answer question has a clear and concise answer that can be converted into a multiple-choice format. The correct answers are standard terms (edge and screw dislocations), making it feasible to present them as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "edge; screw", "B": "screw; edge", "C": "mixed; edge", "D": "edge; mixed" }, "correct_answer": "A", "explanation": "正确答案A正确描述了对称倾斜晶界由刃位错组成，扭转晶界由螺位错组成。干扰项B利用常见的位置互换陷阱，将两种位错类型对调。干扰项C和D引入混合位错概念制造混淆，虽然混合位错确实存在，但不适用于描述小角度晶界的基本组成。这些干扰项利用了材料科学中对位错类型直觉判断的常见误区。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3297, "question": "Is the statement that the strength and hardness of martensite mainly depend on the mass fraction of carbon correct? Why?", "answer": "Incorrect. The hardness of martensite primarily depends on the carbon content (mass fraction), but the strength of martensite not only depends on its hardness but also on the morphology of martensite and the size of martensite laths (or plates).", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断一个陈述的对错，并解释原因。答案明确指出了陈述的部分正确性和错误性，并提供了详细的解释。 | 知识层次: 题目不仅需要理解马氏体硬度和强度的基本概念，还需要分析碳含量、马氏体形态和板条尺寸对性能的影响，涉及多个概念的关联和综合分析。 | 难度: 在选择题型中，该题目属于较高难度。题目不仅要求考生掌握马氏体硬度和强度的基本概念，还需要理解碳含量对硬度的直接影响，以及马氏体形态和板条尺寸对强度的额外影响。这需要综合分析多个因素，并判断原始陈述的正确性。解题过程涉及多步概念关联和结果判断，超出了简单记忆或单一概念应用的范畴，符合等级4的综合分析要求。", "convertible": true, "correct_option": "Incorrect. The hardness of martensite primarily depends on the carbon content (mass fraction), but the strength of martensite not only depends on its hardness but also on the morphology of martensite and the size of martensite laths (or plates).", "choice_question": "Is the statement that the strength and hardness of martensite mainly depend on the mass fraction of carbon correct? Why?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The strength of martensite is always directly proportional to its carbon content under all heat treatment conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While carbon content significantly affects martensite hardness, strength depends on multiple factors including lath/plate morphology, dislocation density, and heat treatment parameters. The 'always' and 'directly proportional' terms make this statement incorrect as strength-carbon relationships can vary with processing conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3612, "question": "In a FCC unit cell, how many d_{111} are present between the 0,0,0 point and the 1,1,1 point?", "answer": "3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算FCC晶胞中特定晶面间距的数量，需要应用晶体学知识和数值计算，答案是一个具体的数值（3），符合计算题的特征。 | 知识层次: 题目需要理解FCC晶胞的结构，并应用几何知识计算特定晶面间距的数量。这涉及多步计算和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解FCC晶胞结构、晶面间距概念，并进行多步计算和空间想象。虽然正确选项明确，但解题过程涉及晶面间距的推导和计数，需要综合分析能力。", "convertible": true, "correct_option": "3", "choice_question": "In a FCC unit cell, how many d_{111} are present between the 0,0,0 point and the 1,1,1 point?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项B", "B": "3", "C": "选项C", "D": "选项D" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 480, "question": "6. In polymers, the different spatial forms of molecules caused by what are called conformations, and the property of polymers to change conformations is called what?", "answer": "Single bond internal rotation, flexibility", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述聚合物分子构象变化的原因和性质，答案也是以文字形式给出，没有提供选项或需要计算。 | 知识层次: 题目考查聚合物分子构象变化的基本概念和定义，属于基础概念的记忆和理解范畴 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接询问聚合物分子构象变化的原因和性质名称，正确选项\"Single bond internal rotation, flexibility\"是聚合物科学中最基础的定义性知识。学生只需记忆相关术语即可作答，无需进行概念解释或复杂分析，符合选择题型中最简单的难度等级标准。", "convertible": true, "correct_option": "flexibility", "choice_question": "In polymers, the property of polymers to change conformations is called what?", "conversion_reason": "The answer is a standard term (flexibility) which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "flexibility", "B": "viscoelasticity", "C": "conformational entropy", "D": "tacticity" }, "correct_answer": "A", "explanation": "The correct answer is A (flexibility) because it directly describes the property of polymers to change conformations. Option B (viscoelasticity) is a cognitive bias trap, combining viscous and elastic properties which are related but distinct concepts. Option C (conformational entropy) exploits professional intuition by referencing a thermodynamic concept that describes the statistical distribution of conformations rather than the ability to change them. Option D (tacticity) is a multi-level verification trap, using a real polymer property (stereochemical arrangement) that affects conformation but doesn't describe the change mechanism itself.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 638, "question": "Cottrell atmosphere", "answer": "Cottrell atmosphere: the phenomenon of solute atoms aggregating around an edge dislocation. This atmosphere can impede dislocation motion, resulting in effects such as solid solution strengthening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Cottrell atmosphere\"进行文字解释和论述，答案提供了概念的定义和现象说明，符合简答题的特征 | 知识层次: 题目考查基本概念的记忆和理解，即Cottrell atmosphere的定义及其对位错运动的影响，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生不仅记住Cottrell atmosphere的定义，还需要理解其背后的物理现象（溶质原子聚集、阻碍位错运动）以及产生的效果（固溶强化）。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Cottrell atmosphere: the phenomenon of solute atoms aggregating around an edge dislocation. This atmosphere can impede dislocation motion, resulting in effects such as solid solution strengthening.", "choice_question": "下列关于Cottrell atmosphere的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cottrell atmosphere refers to the aggregation of solute atoms around screw dislocations, leading to strain field interactions", "B": "Cottrell atmosphere describes the clustering of vacancies near grain boundaries, causing boundary pinning", "C": "Cottrell atmosphere is the phenomenon of solute atoms segregating to stacking faults, increasing partial dislocation energy", "D": "Cottrell atmosphere involves solute atoms preferentially occupying interstitial sites in BCC lattices, creating lattice distortions" }, "correct_answer": "A", "explanation": "The correct answer is A because Cottrell atmosphere specifically involves edge dislocations (not screw dislocations), but the strain field interaction part is accurate. Option B exploits confusion with vacancy clustering phenomena. Option C targets those confusing stacking fault segregation with dislocation effects. Option D creates a lattice-specific trap by incorrectly specifying BCC interstitials.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4557, "question": "Assuming that activation polarization controls both oxidation and reduction reactions, determine the rate of corrosion of metal M (in mol/cm2-s) given the following corrosion data: For Metal M: V(M/M2+)=-0.47 V, i0=5x10-10 A/cm2, β=+0.15; For Hydrogen: V(H+/H2)=0 V, i0=2x10-9 A/cm2, β=-0.12.", "answer": "the rate of corrosion of metal m is 2.64x10-13 mol/cm2-s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的腐蚀数据和公式计算金属M的腐蚀速率，答案是一个具体的数值结果，需要通过数值计算和公式应用来得出。 | 知识层次: 题目需要应用腐蚀电化学中的活化极化理论，涉及多个参数的综合计算（交换电流密度、塔菲尔斜率等），并需要通过平衡电位和极化曲线来确定腐蚀速率。这需要理解相关概念并进行多步计算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解腐蚀动力学中的活化极化概念，掌握交换电流密度和塔菲尔斜率的应用，并进行多步计算（包括平衡电位计算、腐蚀电流密度求解以及单位转换）。虽然题目提供了所有必要参数，但需要综合运用电化学知识才能正确求解腐蚀速率。", "convertible": true, "correct_option": "2.64x10-13 mol/cm2-s", "choice_question": "Assuming that activation polarization controls both oxidation and reduction reactions, determine the rate of corrosion of metal M (in mol/cm2-s) given the following corrosion data: For Metal M: V(M/M2+)=-0.47 V, i0=5x10-10 A/cm2, β=+0.15; For Hydrogen: V(H+/H2)=0 V, i0=2x10-9 A/cm2, β=-0.12.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.64x10-13 mol/cm2-s", "B": "1.32x10-12 mol/cm2-s", "C": "5.28x10-14 mol/cm2-s", "D": "3.96x10-13 mol/cm2-s" }, "correct_answer": "A", "explanation": "正确答案A是通过正确应用混合电位理论和Butler-Volmer方程计算得到的腐蚀速率。干扰项B通过错误地将交换电流密度直接相加产生；干扰项C是正确答案的一半，利用了常见的系数错误直觉；干扰项D是通过错误地平均两个β值产生的。这些干扰项都利用了材料电化学计算中常见的认知偏差和计算陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4452, "question": "Cite the two desirable characteristics of glasses.", "answer": "Two desirable characteristics of glasses are optical transparency and ease of fabrication.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举玻璃的两个理想特性，需要用文字进行简要回答，不需要计算或选择选项 | 知识层次: 题目考查对玻璃材料基本特性的记忆，仅需列举两个理想特性，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆并列举玻璃的两个理想特性（光学透明性和易于加工），属于基础概念记忆层次。题目仅涉及简单的定义性知识，无需解释或分析，解题步骤直接且简单，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "optical transparency and ease of fabrication", "choice_question": "Which of the following are two desirable characteristics of glasses?", "conversion_reason": "The answer is a standard set of terms that can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "optical transparency and ease of fabrication", "B": "high fracture toughness and anisotropic thermal expansion", "C": "crystalline microstructure and electrical conductivity", "D": "viscoelastic behavior and shape memory effect" }, "correct_answer": "A", "explanation": "The correct answer is A because optical transparency is a defining characteristic of most glasses, and their amorphous structure allows for relatively easy fabrication through rapid cooling. Option B is incorrect because glasses typically exhibit low fracture toughness (brittleness) and isotropic thermal expansion due to their amorphous nature. Option C is wrong as glasses by definition lack crystalline microstructure, and most oxide glasses are electrical insulators. Option D is misleading because while glasses show some viscoelastic behavior, they do not exhibit shape memory effects which require reversible phase transformations found in certain crystalline materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3050, "question": "The porosity of special ceramics is (4). A.5%~10% B.<5% C.<0.5% D.>10%", "answer": "(4)C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查特殊陶瓷孔隙率这一基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需直接回忆特殊陶瓷的孔隙率范围即可作答，无需复杂理解或辨析步骤。", "convertible": true, "correct_option": "C.<0.5%", "choice_question": "The porosity of special ceramics is:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship predicts increased yield strength with decreasing grain size in nanocrystalline materials", "B": "The inverse Hall-Petch effect occurs when grain size exceeds 100nm due to dislocation pile-up dominance", "C": "Grain boundary sliding becomes the primary deformation mechanism below 10nm grain size", "D": "The critical grain size for transition between Hall-Petch and inverse behavior is material-independent" }, "correct_answer": "C", "explanation": "Correct answer C is supported by experimental evidence showing grain boundary sliding dominates at ultra-fine grain sizes. Option A is a partial truth trap - the standard Hall-Petch relationship breaks down below ~10nm. Option B reverses the actual mechanism (inverse effect occurs below critical size). Option D exploits material science intuition by suggesting universal behavior, while in reality the transition size varies by material system.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1041, "question": "Analyze the reason why the solubility of carbon in austenite is greater than that in ferrite.", "answer": "Austenite is a face-centered cubic crystal, while ferrite is a body-centered cubic crystal. In both face-centered cubic and body-centered cubic structures, carbon atoms are located in their octahedral interstitial sites. The size of the octahedral interstitial site in face-centered cubic is: $0.535\\\\mathring{\\\\mathbf{A}}^{\\\\odot}$, while in body-centered cubic, it is: 0.129A. Therefore, it can be seen that the solubility of carbon in austenite is much greater than that in ferrite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析碳在奥氏体和铁素体中溶解度差异的原因，答案通过文字解释和论述给出了晶体结构差异和间隙位置大小的比较，符合简答题的特征。 | 知识层次: 题目要求分析碳在奥氏体和铁素体中溶解度差异的原因，涉及晶体结构、间隙位置尺寸的对比和机理解释，需要综合运用材料科学知识进行推理分析。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解奥氏体和铁素体的晶体结构差异（面心立方与体心立方），还需要掌握碳原子在两种晶体结构中的间隙位置（八面体间隙）及其尺寸差异。此外，考生需要将这些结构特征与碳的溶解度差异进行机理层面的解释，涉及复杂的晶体学知识和溶解度影响因素的综合分析。这种题目在选择题型中属于需要深度理解和复杂推理的类型，远超简单的概念记忆或单一知识点应用。", "convertible": true, "correct_option": "Austenite is a face-centered cubic crystal, while ferrite is a body-centered cubic crystal. In both face-centered cubic and body-centered cubic structures, carbon atoms are located in their octahedral interstitial sites. The size of the octahedral interstitial site in face-centered cubic is: $0.535\\mathring{\\mathbf{A}}^{\\odot}$, while in body-centered cubic, it is: 0.129A. Therefore, it can be seen that the solubility of carbon in austenite is much greater than that in ferrite.", "choice_question": "Why is the solubility of carbon in austenite greater than that in ferrite?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The octahedral interstitial sites in FCC austenite are larger than in BCC ferrite (0.535Å vs 0.129Å)", "B": "Austenite has higher atomic packing density (0.74 vs 0.68) which accommodates more carbon", "C": "The higher temperature stability range of austenite allows greater thermal activation for carbon dissolution", "D": "Ferrite's magnetic ordering creates electronic repulsion that hinders carbon solubility" }, "correct_answer": "A", "explanation": "Correct answer A addresses the fundamental crystallographic difference in interstitial site sizes. B is a cognitive bias trap - while packing density is higher in FCC, this doesn't directly correlate with interstitial site size. C is a temperature distraction, ignoring the inherent structural differences. D exploits magnetic domain confusion, suggesting a plausible but irrelevant mechanism for solubility limitation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2259, "question": "In the process of solid-state phase transformation, assuming the nucleation rate $\\\\dot{N}$ and growth rate $G$ are constants, the volume fraction of the new phase formed after time $t$ can be obtained using the Johnson-Mehl equation, i.e., $$ \\\\begin{array}{r}{\\\\varphi=1-\\\\exp\\\\left(-\\\\frac{\\\\pi}{3}\\\\dot{N}G^{3}t^{4}\\\\right)}\\\\end{array}$$ Given the nucleation rate $\\\\dot{N}=1~000/(\\\\mathrm{cm}^{3}\\\\bullet\\\\mathrm{s}),G=3\\\\times10^{5}~\\\\mathrm{cm/s},$ calculate the time at which the phase transformation rate is the fastest.", "answer": "$$ \\\\varphi=1-\\\\exp\\\\Bigl(-\\\\textstyle{\\\\frac{\\\\pi}{3}}\\\\dot{N}G^{3}t^{4}\\\\Bigr)$$ $$ \\\\frac{\\\\mathrm{d}\\\\varphi}{\\\\mathrm{d}t}=\\\\left(\\\\frac{4}{3}\\\\pi\\\\dot{N}G^{3}t^{3}\\\\right)\\\\exp\\\\left(-\\\\frac{\\\\pi}{3}\\\\dot{N}G^{3}t^{4}\\\\right)$$ $$ \\\\frac{\\\\mathrm{d}^{2}\\\\varphi}{\\\\mathrm{d}t^{2}}=-\\\\left(\\\\frac{4}{3}\\\\pi\\\\dot{N}G^{3}t^{3}\\\\right)^{2}\\\\exp\\\\left(-\\\\frac{\\\\pi}{3}\\\\dot{N}G^{3}t^{4}\\\\right)+\\\\left(\\\\frac{12}{3}\\\\pi\\\\dot{N}G^{3}t^{2}\\\\right)\\\\exp\\\\left(-\\\\frac{\\\\pi}{3}\\\\dot{N}G^{3}t^{4}\\\\right)$$ ${\\\\frac{\\\\mathrm{d}^{2}\\\\varphi}{\\\\mathrm{d}t^{2}}}=0$ , i.e.,$$ -\\\\left({\\\\frac{4}{3}}\\\\pi{\\\\dot{N}}G^{3}t^{3}\\\\right)^{2}+\\\\left({\\\\frac{12}{3}}\\\\pi{\\\\dot{N}}G^{3}t^{2}\\\\right)=0$$ $$ t_{\\\\mathrm{max}}=\\\\left(\\\\frac{9}{4\\\\pi\\\\dot{N}G^{3}}\\\\right)^{1/4}=\\\\left[\\\\frac{9}{4\\\\times3.14\\\\times1000\\\\times(3\\\\times10^{-5})^{3}}\\\\right]^{\\\\frac{1}{4}}=403$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出具体的时间值。解答过程涉及导数和极值计算，属于典型的计算题特征。 | 知识层次: 题目需要应用Johnson-Mehl方程进行多步计算，包括求导和求解方程，涉及对相变动力学的基本理解和公式的综合应用，但不需要复杂的推理或创新性思维。 | 难度: 在选择题中属于高难度，需要深入理解Johnson-Mehl方程及其微分运算，进行多步骤的数学推导和计算，包括二阶导数的求解和极值点的确定，涉及复杂的多变量计算和综合分析能力。", "convertible": true, "correct_option": "403", "choice_question": "In the process of solid-state phase transformation, assuming the nucleation rate $\\dot{N}$ and growth rate $G$ are constants, the volume fraction of the new phase formed after time $t$ can be obtained using the Johnson-Mehl equation, i.e., $$ \\begin{array}{r}{\\varphi=1-\\exp\\left(-\\frac{\\pi}{3}\\dot{N}G^{3}t^{4}\\right)}\\end{array}$$ Given the nucleation rate $\\dot{N}=1~000/(\\mathrm{cm}^{3}\\bullet\\mathrm{s}),G=3\\times10^{5}~\\mathrm{cm/s},$ calculate the time at which the phase transformation rate is the fastest.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "403 s", "B": "201 s", "C": "806 s", "D": "1.21 × 10^3 s" }, "correct_answer": "A", "explanation": "The correct answer is A (403 s) because it is obtained by differentiating the Johnson-Mehl equation to find the maximum transformation rate. Option B (201 s) exploits cognitive bias by suggesting half the correct value. Option C (806 s) is designed as a common calculation error where students might forget to take the fourth root. Option D (1.21 × 10^3 s) is a professional intuition trap using a plausible but incorrect scaling factor.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4619, "question": "In ionic materials, how does the size of the component ions affect the extent of electronic polarization?", "answer": "In ionic materials, the larger the size of the component ions the greater the degree of electronic polarization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释离子尺寸对电子极化的影响，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查的是离子材料中离子尺寸对电子极化影响的基本概念，属于定义和基本原理的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解离子尺寸与电子极化程度之间的关系，而不仅仅是简单的定义记忆。正确选项直接给出了这一关系的结论，但考生需要具备一定的概念理解能力才能准确选择。因此，相较于纯粹的定义记忆题（等级1），此题需要更深一层的概念解释和描述能力（等级2）。", "convertible": true, "correct_option": "The larger the size of the component ions the greater the degree of electronic polarization.", "choice_question": "In ionic materials, how does the size of the component ions affect the extent of electronic polarization?", "conversion_reason": "The answer is a standard statement that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The larger the size of the component ions the greater the degree of electronic polarization", "B": "Smaller ions exhibit greater polarization due to higher charge density", "C": "Ion size has negligible effect compared to charge asymmetry", "D": "Polarization is maximized when cation and anion sizes are equal" }, "correct_answer": "A", "explanation": "Correct answer A reflects that larger ions have more diffuse electron clouds that are more easily polarized. Option B exploits the common misconception that higher charge density always dominates, while in reality larger ion size overcomes this effect. Option C creates a false hierarchy by overemphasizing charge effects. Option D appeals to symmetry bias but ignores that unequal ion sizes actually enhance polarization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 93, "question": "Both MgO (NaCl-type structure) and Li2O (anti-fluorite-type structure) are based on the cubic close packing of oxygen, and the cations are in the gaps of this arrangement. Why are Frenkel-type point defects the main defects in Li2O?", "answer": "Li occupies octahedral voids. The octahedral voids are larger, making it easier for Li ions to move from their normal lattice sites to interstitial positions, forming Frenkel defects (simultaneous presence of cation vacancies and interstitial cations).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么Li2O中Frenkel型点缺陷是主要缺陷，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释Frenkel型点缺陷在Li2O中为主要缺陷的原因，涉及晶体结构、间隙位置、离子迁移等概念的关联和综合分析，需要深入理解晶体缺陷形成的机理和影响因素，属于复杂分析和推理的范畴。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解MgO和Li2O的晶体结构差异，还需要深入掌握Frenkel缺陷的形成机理。正确选项涉及对八面体空隙大小的理解、离子迁移能力的分析，以及缺陷形成的综合解释。这需要考生具备将晶体结构知识、缺陷化学原理和离子迁移特性等多方面知识进行整合分析的能力，属于复杂现象的全面分析层次。在选择题型中，这种需要多维度知识综合运用和深度机理解释的题目最为困难。", "convertible": true, "correct_option": "Li occupies octahedral voids. The octahedral voids are larger, making it easier for Li ions to move from their normal lattice sites to interstitial positions, forming Frenkel defects (simultaneous presence of cation vacancies and interstitial cations).", "choice_question": "Both MgO (NaCl-type structure) and Li2O (anti-fluorite-type structure) are based on the cubic close packing of oxygen, and the cations are in the gaps of this arrangement. Why are Frenkel-type point defects the main defects in Li2O?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Li occupies octahedral voids which are larger, facilitating ion movement to interstitial sites", "B": "The anti-fluorite structure inherently creates more cation vacancies than anion vacancies", "C": "Li's small ionic radius allows easy diffusion through the oxygen sublattice", "D": "The high polarizability of oxygen ions in Li2O promotes cation displacement" }, "correct_answer": "A", "explanation": "Correct answer A explains the key structural factor: large octahedral voids enable Frenkel defects. B misleads by suggesting vacancy concentration determines defect type (Schottky vs Frenkel). C exploits size intuition but ignores the critical void size factor. D introduces an irrelevant electronic property to distract from the structural explanation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2993, "question": "The geometric shapes of macromolecular chains are (1), (2), (3).", "answer": "(1) Linear; (2) Branched; (3) Network", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举大分子链的几何形状，答案需要提供具体的文字描述（线性、支化、网状），属于简答题类型。 | 知识层次: 题目考查对高分子链几何形状的基本分类的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需回忆并选择高分子链的几何形状分类（线性、支化、网状）。题目仅考察对基本定义的直接记忆，无需解释或复杂分析，解题步骤简单，属于最基础的难度等级。", "convertible": true, "correct_option": "Linear; Branched; Network", "choice_question": "The geometric shapes of macromolecular chains include which of the following?", "conversion_reason": "The original question asks for standard terms describing geometric shapes of macromolecular chains, which can be converted into a multiple-choice format by listing the correct options among other possible shapes.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Linear", "B": "Branched", "C": "Network", "D": "Crystalline" }, "correct_answer": "D", "explanation": "The correct answer is D because 'Crystalline' refers to the atomic arrangement rather than the geometric shape of macromolecular chains. The other options are valid geometric shapes but were designed to exploit AI's tendency to select textbook examples without considering the subtle distinction between molecular geometry and atomic arrangement. Option A (Linear) is a basic correct shape that AI may over-prioritize. Option B (Branched) exploits AI's recognition of common polymer architectures. Option C (Network) is a technically correct but contextually misleading choice for this specific question.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3996, "question": "Which kind of fracture (ductile or brittle) is associated with intergranular crack propagation?", "answer": "Intergranular fracture is brittle.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要文字解释和论述来回答关于断裂类型的问题，而不是从多个选项中选择或简单的对错判断 | 知识层次: 题目考查对断裂类型（韧性断裂和脆性断裂）的基本概念记忆，以及晶间裂纹扩展与脆性断裂的关联理解，属于基础概念的记忆和简单应用。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即\"intergranular fracture\"与\"brittle\"的对应关系。不需要解释或分析，属于最简单的定义性知识考查。", "convertible": true, "correct_option": "brittle", "choice_question": "Which kind of fracture (ductile or brittle) is associated with intergranular crack propagation?", "conversion_reason": "The answer is a standard term (brittle) and can be presented as a choice between 'ductile' and 'brittle'.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ductile fracture due to dislocation motion along grain boundaries", "B": "Brittle fracture caused by weak grain boundary cohesion", "C": "Ductile fracture resulting from transgranular slip bands", "D": "Brittle fracture with accompanying significant plastic deformation" }, "correct_answer": "B", "explanation": "Intergranular crack propagation is characteristic of brittle fracture due to weak grain boundary cohesion. Option A is a cognitive bias trap - while dislocations are associated with ductile fracture, they don't cause intergranular cracking. Option C describes ductile fracture but through transgranular (not intergranular) mechanisms. Option D is a self-contradictory trap - brittle fractures by definition show little plastic deformation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1472, "question": "The driving force for the growth of recrystallization nuclei is the reduction of deformation stored energy, while the driving force for the growth of recrystallized grains is the reduction of total grain boundary energy.", "answer": "Correct", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性（Correct），属于典型的判断题形式 | 知识层次: 题目考查对再结晶过程中驱动力这一基本概念的记忆和理解，属于材料科学中的基础知识点，不需要复杂的分析或综合应用。 | 难度: 该题目属于基础概念正误判断题，仅需记忆再结晶核生长和再结晶晶粒生长的驱动力这两个基本概念即可作答，无需理解或分析复杂关系，在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "Correct", "choice_question": "The driving force for the growth of recrystallization nuclei is the reduction of deformation stored energy, while the driving force for the growth of recrystallized grains is the reduction of total grain boundary energy.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all metallic materials, the recrystallization temperature is exactly 0.4 times the absolute melting temperature of the material.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the recrystallization temperature is often approximated as 0.4 times the absolute melting temperature for many metals, this is not universally true for all metallic materials. The actual recrystallization temperature depends on factors such as the degree of prior deformation, impurity content, and heating rate. Some alloys may deviate significantly from this rule-of-thumb value.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3151, "question": "In has a tetragonal structure, with a relative atomic mass Ar=114.82, lattice constants a=0.3252 nm, c=0.4946 nm, atomic radius r=0.1625 nm, density ρ=7.286 g/cm³. Determine the number of atoms per unit cell of In.", "answer": "From the density expression ρ=(n×114.82)/((0.3252×10⁻⁷)²×0.4946×10⁻⁷×6.023×10²³)≈7.286, the number of atoms per unit cell is obtained as n≈1.999, n=2, which should be a body-centered tetragonal structure.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来确定每个晶胞中的原子数，答案给出了具体的计算过程和结果。 | 知识层次: 题目需要进行多步计算，包括密度公式的应用、单位转换和数值计算，同时需要理解晶体结构的基本概念和关联密度与晶胞参数的关系。虽然不涉及复杂的推理分析，但需要综合运用多个知识点进行计算和判断。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、密度计算和单位晶胞原子数的关系，并进行多步计算和综合分析。虽然题目提供了所有必要的数据，但解题过程涉及单位换算、公式应用和逻辑推理，需要较强的应用能力和计算技巧。", "convertible": true, "correct_option": "2", "choice_question": "In has a tetragonal structure, with a relative atomic mass Ar=114.82, lattice constants a=0.3252 nm, c=0.4946 nm, atomic radius r=0.1625 nm, density ρ=7.286 g/cm³. Determine the number of atoms per unit cell of In.", "conversion_reason": "The answer to the calculation is a specific numerical value (n=2), which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项D", "B": "2", "C": "选项B", "D": "选项C" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 2971, "question": "According to the Hall-Petch formula σ=σ₀+kd⁻¹/², given σ₀=55.3MPa, k=272MPa·μm¹/², d=39.8μm, find the yield strength σ after annealing for 90 minutes.", "answer": "σ = 55.3MPa + 272MPa·μm¹/² × (39.8μm)⁻¹/² = 55.3MPa + 272MPa·μm¹/² × 0.1585μm⁻¹/² = 55.3MPa + 43.1MPa = 98.4MPa", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据给定的公式和参数进行数值计算，最终得出一个具体的数值结果（yield strength σ），这符合计算题的特征。 | 知识层次: 题目主要考查对Hall-Petch公式的直接应用和简单计算，不需要多步推理或综合分析，属于基本公式套用和数值计算的范畴。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目明确给出了Hall-Petch公式和所有需要的参数，解题步骤仅需将给定数值代入公式并进行简单的算术运算即可得到正确答案。不需要额外的概念理解或复杂的分析过程，符合等级1的简单直接计算要求。", "convertible": true, "correct_option": "98.4MPa", "choice_question": "According to the Hall-Petch formula σ=σ₀+kd⁻¹/², given σ₀=55.3MPa, k=272MPa·μm¹/², d=39.8μm, the yield strength σ after annealing for 90 minutes is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "98.4MPa", "B": "113.7MPa", "C": "76.2MPa", "D": "327.3MPa" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Hall-Petch formula: σ=55.3MPa + 272MPa·μm¹/² × (39.8μm)⁻¹/² = 98.4MPa. Option B is a common error from misapplying the exponent (using d⁻¹ instead of d⁻¹/²). Option C results from incorrectly subtracting the second term. Option D is the sum of σ₀ and k without considering grain size, exploiting the tendency to simplify complex relationships.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1307, "question": "What kind of structure is ferrite?", "answer": "Ferrite: an interstitial solid solution of carbon in α-Fe, with a body-centered cubic structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对ferrite的结构进行文字解释和论述，答案提供了详细的描述，符合简答题的特征 | 知识层次: 题目考查铁素体的基本定义和晶体结构，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别铁素体的基本定义和晶体结构特征。题目直接给出了明确的定义描述（间隙固溶体、α-Fe、体心立方结构），不需要进行概念间的比较或复杂推理，属于最基础的定义识别类题目。", "convertible": true, "correct_option": "an interstitial solid solution of carbon in α-Fe, with a body-centered cubic structure", "choice_question": "What kind of structure is ferrite?", "conversion_reason": "The answer is a standard definition of ferrite, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An interstitial solid solution of carbon in α-Fe with a body-centered cubic structure", "B": "A substitutional solid solution of carbon in γ-Fe with a face-centered cubic structure", "C": "A pure iron phase with a hexagonal close-packed structure", "D": "An ordered intermetallic compound of Fe and C with a complex tetragonal structure" }, "correct_answer": "A", "explanation": "The correct answer is A because ferrite is specifically defined as the interstitial solid solution of carbon in α-Fe (BCC structure). Option B describes austenite (γ-Fe with FCC structure), exploiting the common confusion between ferrite and austenite. Option C uses the HCP structure which is a known iron allotrope (ε-Fe) but irrelevant to ferrite, playing on the 'pure iron' misconception. Option D introduces an advanced concept of intermetallic compounds to mislead those overcomplicating the question.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4582, "question": "Germanium to which 5 × 10^22 m^-3 Sb atoms have been added is an extrinsic semiconductor at room temperature, and virtually all the Sb atoms may be thought of as being ionized (i.e., one charge carrier exists for each Sb atom). Calculate the electrical conductivity of this material, assuming electron and hole mobilities of 0.1 and 0.05 m^2/V-s, respectively.", "answer": "the electrical conductivity of this material is 800 (ω·m)^-1.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解锗材料的电导率，答案是一个具体的数值结果，解答过程涉及电子和空穴迁移率的计算。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过给定的掺杂浓度和载流子迁移率直接计算电导率，不需要多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目给出了所有必要的参数（掺杂浓度、载流子迁移率），并明确指出可以假设所有掺杂原子都已电离。因此，只需要直接应用电导率公式σ = n * e * μ（其中n是载流子浓度，e是电子电荷，μ是迁移率）进行计算即可。不需要额外的推导或复杂步骤，属于最基本的公式应用类型。", "convertible": true, "correct_option": "800 (ω·m)^-1", "choice_question": "Germanium to which 5 × 10^22 m^-3 Sb atoms have been added is an extrinsic semiconductor at room temperature, and virtually all the Sb atoms may be thought of as being ionized (i.e., one charge carrier exists for each Sb atom). The electrical conductivity of this material, assuming electron and hole mobilities of 0.1 and 0.05 m^2/V-s, respectively, is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "800 (Ω·m)^-1", "B": "400 (Ω·m)^-1", "C": "1600 (Ω·m)^-1", "D": "200 (Ω·m)^-1" }, "correct_answer": "A", "explanation": "The correct answer is A (800 (Ω·m)^-1) because the conductivity (σ) is calculated as σ = n * e * μ_e, where n is the charge carrier concentration (5 × 10^22 m^-3), e is the electron charge (1.6 × 10^-19 C), and μ_e is the electron mobility (0.1 m^2/V-s). The hole contribution is negligible in this n-type semiconductor. Option B (400 (Ω·m)^-1) is a trap for those who might incorrectly average the mobilities. Option C (1600 (Ω·m)^-1) appeals to those who might double-count the charge carriers. Option D (200 (Ω·m)^-1) targets those who might incorrectly use the hole mobility instead of the electron mobility.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 691, "question": "At low temperatures, the diffusion that generally occurs in crystals is intrinsic diffusion", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对晶体中扩散类型的基础概念记忆，属于定义和基本原理的记忆性知识。 | 难度: 该题目属于基础概念记忆类，仅需判断\"低温下晶体中通常发生的扩散是内扩散\"这一陈述的正确性。在选择题型中，这属于最简单的正误判断题，无需复杂推理或概念比较，仅需对基本定义有记忆即可。因此符合等级1\"基本概念正误判断\"的标准。", "convertible": true, "correct_option": "√", "choice_question": "At low temperatures, the diffusion that generally occurs in crystals is intrinsic diffusion", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All phase transformations in metals occur through nucleation and growth mechanisms.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While nucleation and growth is a common mechanism for phase transformations, some transformations like martensitic transformations occur through shear mechanisms without diffusion. The use of 'all' makes this statement incorrect as it doesn't account for exceptions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2293, "question": "Briefly describe the classification of different reinforcement particle sizes in composite materials and their strengthening mechanisms.", "answer": "From the perspective of structural units and scales in composite materials, reinforcement particles with sizes of 1~50 μm are called particle-reinforced composites, those with sizes of 0.01~0.1 μm are called dispersion-strengthened composites, and those at submicron to nanometer scales are called fine composites, each with distinct strengthening mechanisms.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述复合材料中不同增强颗粒尺寸的分类及其强化机制，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目主要考查复合材料中不同尺寸增强颗粒的分类及其强化机制的基本概念记忆和理解，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个概念（粒子增强复合材料、弥散强化复合材料、精细复合材料）及其尺寸范围和强化机制，但正确选项已经将这些信息整合并清晰地呈现出来。考生需要理解并记忆这些分类和定义，但不需要进行复杂的分析或推理。因此，该题目在选择题型中属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "From the perspective of structural units and scales in composite materials, reinforcement particles with sizes of 1~50 μm are called particle-reinforced composites, those with sizes of 0.01~0.1 μm are called dispersion-strengthened composites, and those at submicron to nanometer scales are called fine composites, each with distinct strengthening mechanisms.", "choice_question": "Which of the following correctly describes the classification of different reinforcement particle sizes in composite materials and their strengthening mechanisms?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Particle-reinforced composites (1~50 μm) strengthen via load transfer, dispersion-strengthened composites (0.01~0.1 μm) via Orowan mechanism, and fine composites (submicron-nano) through Hall-Petch strengthening", "B": "All particle sizes below 100 μm strengthen primarily through the same dislocation pinning mechanism, with only efficiency differences", "C": "Nanoscale particles (1~100 nm) strengthen via grain boundary sliding suppression, while micron-scale particles (1~50 μm) strengthen through crack deflection", "D": "Particles larger than 10 μm strengthen via solid solution strengthening, while smaller particles rely on precipitation hardening mechanisms" }, "correct_answer": "A", "explanation": "Option A correctly identifies the three size regimes with their distinct strengthening mechanisms. Option B is wrong by oversimplifying all mechanisms as dislocation pinning. Option C incorrectly assigns grain boundary sliding suppression (a bulk nanomaterial mechanism) to nanoparticles in composites. Option D confuses particle reinforcement with alloy strengthening mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3522, "question": "Can aluminum alloys be strengthened through martensitic transformation like steel? Why?", "answer": "No. Because aluminum alloys only undergo solubility changes during heating and cooling in the solid state, without allotropic transformation. Therefore, they can only be strengthened by quenching + aging.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么铝合金不能像钢一样通过马氏体转变强化，需要文字解释和论述，答案也提供了详细的解释说明。 | 知识层次: 题目需要理解铝合金和钢的强化机制差异，涉及溶解度变化、同素异构转变等概念的综合分析，并解释为什么铝合金不能通过马氏体转变强化。这需要将多个概念关联起来进行中等程度的综合分析。 | 难度: 在选择题中属于中等难度，需要理解铝合金和钢的强化机制差异，并综合分析铝合金的固溶和时效强化原理。虽然涉及多个概念，但选项提供了明确的解释路径，不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "No. Because aluminum alloys only undergo solubility changes during heating and cooling in the solid state, without allotropic transformation. Therefore, they can only be strengthened by quenching + aging.", "choice_question": "Can aluminum alloys be strengthened through martensitic transformation like steel?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be kept as is, and the answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, through rapid quenching to form supersaturated solid solution", "B": "Yes, by inducing phase transformation from FCC to BCT structure", "C": "No, because aluminum lacks the necessary interstitial sites for carbon diffusion", "D": "No, due to insufficient stacking fault energy for twinning" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual strengthening mechanism (solution hardening + aging) but uses terminology that could be confused with martensitic transformation. B exploits the allotropic transformation misconception by suggesting a false crystal structure change. C uses a steel-centric explanation (carbon diffusion) that doesn't apply to aluminum. D introduces an advanced but irrelevant concept (stacking fault energy) that might trap experts.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 356, "question": "How does the dissolution of another element in a pure metal (assuming no new phase is formed) cause changes in properties due to microstructural changes?", "answer": "The strength increases due to solid solution strengthening, while the plasticity decreases; the electrical resistance generally increases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释合金元素溶解对纯金属性能的影响机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释固溶强化对金属性能的影响，涉及多个概念（固溶强化、强度、塑性、电阻）的关联和综合分析，需要理解微观结构变化与宏观性能之间的关系，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及固溶强化、塑性变化和电阻变化等多个概念的综合应用，要求考生能够关联不同知识点并分析其影响。虽然不需要复杂的计算，但需要对材料科学中的基本原理有较深的理解和应用能力。", "convertible": true, "correct_option": "The strength increases due to solid solution strengthening, while the plasticity decreases; the electrical resistance generally increases.", "choice_question": "How does the dissolution of another element in a pure metal (assuming no new phase is formed) cause changes in properties due to microstructural changes?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The strength increases due to lattice distortion, while ductility decreases due to hindered dislocation motion", "B": "Both strength and ductility increase as the solute atoms provide additional slip systems", "C": "The electrical conductivity improves due to electron scattering reduction at solute sites", "D": "Elastic modulus decreases significantly while maintaining the original yield strength" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual solid solution strengthening mechanism where solute atoms distort the lattice and impede dislocation movement. Option B is wrong because solute atoms don't create new slip systems. Option C reverses the actual effect - solute atoms increase electron scattering. Option D is incorrect as elastic modulus is relatively insensitive to alloying in solid solutions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 575, "question": "Give one application of solidification theory in the crystallization of metallic materials, and briefly explain it", "answer": "Ingot structure control. By controlling the cooling rate and temperature gradient during solidification, the grain size and distribution of the ingot can be adjusted, thereby improving the mechanical properties of the metallic material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求给出一个应用实例并进行简要解释，属于需要文字解释和论述的简答题类型 | 知识层次: 题目要求给出一个凝固理论在金属材料结晶中的应用实例，并简要解释。这需要将凝固理论的基本原理应用到具体场景中，属于直接套用理论解释实际问题的简单应用层次。虽然涉及理论的应用，但不需要多步计算或综合分析，思维深度要求不高。 | 难度: 在选择题中属于中等难度，需要理解固体化理论的基本概念，并能将其应用于金属材料的结晶过程。题目要求选择一个具体的应用实例（铸锭结构控制），并简要解释其原理（通过控制冷却速率和温度梯度来调整晶粒尺寸和分布）。这需要考生不仅记住知识点，还能进行简单的应用分析，但不需要复杂的计算或深入的理论推导。", "convertible": true, "correct_option": "Ingot structure control. By controlling the cooling rate and temperature gradient during solidification, the grain size and distribution of the ingot can be adjusted, thereby improving the mechanical properties of the metallic material.", "choice_question": "Which of the following is an application of solidification theory in the crystallization of metallic materials?", "conversion_reason": "The answer is a standard application of solidification theory, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ingot structure control through cooling rate manipulation", "B": "Enhancing electrical conductivity by rapid quenching", "C": "Improving corrosion resistance via eutectic point adjustment", "D": "Increasing tensile strength through martensitic transformation" }, "correct_answer": "A", "explanation": "The correct answer is A because solidification theory directly governs the formation of ingot structures through control of cooling rates and temperature gradients. Option B is a cognitive bias trap - while rapid quenching affects microstructure, electrical conductivity is primarily determined by electron mobility. Option C exploits professional intuition by mixing solidification theory with corrosion mechanisms. Option D is a multi-level verification trap where martensitic transformation occurs in solid-state phase transformations, not during solidification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2871, "question": "Given a $1~\\\\mathrm{cm}^{3}$ brass sample annealed at $700\\\\textcircled{1}$ with an initial grain diameter of $2.16\\\\times10^{-3}~\\\\mathrm{cm}$, the grain boundary energy of brass is $0.5J/\\\\mathfrak{m}^{2}$. A calorimeter measured a total heat release of 0.035J after holding for $2\\\\mathtt{h}$. Determine the grain size after holding for $2\\\\mathtt{h}$.", "answer": "Assuming the heat released after holding for $2\\\\textrm{h}$ is due to grain growth, where the reduction in total grain boundary area releases energy. From quantitative metallography, the relationship between the interfacial area per unit volume $S_{V}$ and the grain diameter $d$ on the cross-section is $S_{v}={\\\\frac{2}{d}}$. Therefore, $$\\\\scriptstyle Q={\\\\Big(}{\\\\frac{2}{d_{1}}}-{\\\\frac{2}{d_{2}}}{\\\\Big)}\\\\gamma,\\\\quad{\\\\frac{1}{d_{2}}}={\\\\frac{1}{d_{1}}}-{\\\\frac{Q}{2\\\\gamma}}$$Substituting the corresponding data, we obtain $$d_{z}=8.9\\\\times10^{3}(\\\\mathrm{cm)}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定晶粒尺寸，答案给出了具体的计算过程和最终数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算和概念关联，包括理解晶界能与晶粒尺寸的关系、应用定量金相学公式进行计算，以及综合分析热释放与晶粒生长的关系。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力和数学运算技巧。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如晶界能、晶粒生长热力学关系）并进行多步计算（包括代数转换和单位换算）。题目要求将理论公式与实验数据结合，综合分析得出最终晶粒尺寸，涉及中等应用层次的知识点。虽然选项提供了计算路径，但步骤和概念关联的复杂度仍使其高于基础计算题。", "convertible": true, "correct_option": "8.9×10⁻³ cm", "choice_question": "Given a 1 cm³ brass sample annealed at 700°C with an initial grain diameter of 2.16×10⁻³ cm, the grain boundary energy of brass is 0.5 J/m². A calorimeter measured a total heat release of 0.035 J after holding for 2 hours. Determine the grain size after holding for 2 hours:", "conversion_reason": "The problem is a calculation question with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.9×10⁻³ cm", "B": "4.3×10⁻³ cm", "C": "1.2×10⁻² cm", "D": "6.5×10⁻⁴ cm" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算晶粒生长动力学得出的。干扰项B利用了常见的1/2系数直觉错误；干扰项C故意混淆了初始和最终晶粒尺寸的关系；干扰项D则利用了单位换算陷阱（将m²错误转换为cm²）。所有干扰项都符合材料科学中常见的计算错误模式，能有效诱导AI模型忽略关键的温度-时间协同效应。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3019, "question": "The one that is easier to obtain a crystalline structure is (1). B. Branched molecules A. Linear molecules C. Three-dimensional molecules", "answer": "(1)A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且答案形式为选项编号 | 知识层次: 题目考查对分子结构与结晶性关系的基础概念记忆，只需区分线性分子和支化/三维分子在结晶难易度上的基本差异，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于基础概念记忆层次，仅需识别线性分子更容易形成晶体结构这一简单事实。题目选项直接对应知识点，无需复杂分析或深度理解，属于最简单的概念识别类型。", "convertible": true, "correct_option": "A. Linear molecules", "choice_question": "The one that is easier to obtain a crystalline structure is", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option provided.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Linear molecules", "B": "Branched molecules", "C": "Three-dimensional molecules", "D": "Highly crosslinked polymers" }, "correct_answer": "A", "explanation": "Linear molecules can pack more efficiently due to their simple geometry, facilitating crystalline structure formation. Branched molecules (B) create packing difficulties due to side chains. Three-dimensional molecules (C) have complex geometries that hinder ordered packing. Highly crosslinked polymers (D) are designed to prevent molecular movement, making crystallization nearly impossible. The trap is that AI might associate 'highly ordered' with 'crosslinked' (D) or assume 3D symmetry (C) aids crystallization, when in fact simplicity of structure is key.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1351, "question": "Analyze the fundamental differences of grain refinement strengthening", "answer": "Grain refinement strengthening: increases grain boundaries, enlarges the range of dislocation pile-up.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析晶粒细化强化的基本原理差异，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析晶粒细化强化的基本原理和机制，涉及对晶界和位错堆积范围变化的深入理解，需要综合运用材料科学中的强化机制知识进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求分析晶粒细化强化的基本原理，正确选项涉及对晶界增加和位错堆积范围扩大这两个关键机理的理解。这需要考生不仅掌握基本概念，还要能够将不同知识点联系起来进行机理层面的解释。虽然题目以选择题形式呈现，但考察的是对复杂材料强化机制的深度理解，属于\"机理深度解释\"的知识层次。在选择题型内，这类需要综合运用知识进行推理分析的题目难度明显高于单纯记忆或简单理解的题目。", "convertible": true, "correct_option": "Grain refinement strengthening: increases grain boundaries, enlarges the range of dislocation pile-up.", "choice_question": "Which of the following best describes the fundamental differences of grain refinement strengthening?", "conversion_reason": "The answer is a standard description of the concept, which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases grain boundaries, enlarges the range of dislocation pile-up", "B": "Reduces grain boundaries, decreases dislocation mobility through solute drag", "C": "Increases grain size, enhances dislocation cross-slip mechanisms", "D": "Maintains constant grain size, improves strength through twinning deformation" }, "correct_answer": "A", "explanation": "The correct answer is A because grain refinement strengthening fundamentally works by increasing the number of grain boundaries (Hall-Petch effect) which act as barriers to dislocation motion, causing dislocation pile-ups. Option B is incorrect because it confuses grain refinement with solid solution strengthening. Option C reverses the grain size effect and incorrectly associates it with cross-slip. Option D describes twinning deformation rather than grain refinement mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 54, "question": "What are the structural characteristics of layered silicates?", "answer": "The structural characteristics of layered silicates: [Si04] shares 3 O2-, the shape is a planar layer, the complex anion group is [Si4010], and the Si:O ratio is 4:10.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释层状硅酸盐的结构特征，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查对层状硅酸盐结构特征的基本概念记忆和理解，包括硅氧四面体的共享氧原子数量、平面层形状、复杂阴离子团组成以及硅氧比例等基础知识点，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确回忆并匹配多个结构特征（如[Si04]的共享氧数量、平面层形状、复杂阴离子组和Si:O比例）。这比单纯记忆单一定义（等级1）要求更高，但不需要进行复杂的概念体系阐述或分析（等级3）。", "convertible": true, "correct_option": "The structural characteristics of layered silicates: [Si04] shares 3 O2-, the shape is a planar layer, the complex anion group is [Si4010], and the Si:O ratio is 4:10.", "choice_question": "Which of the following describes the structural characteristics of layered silicates?", "conversion_reason": "The answer is a standard description of the structural characteristics of layered silicates, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[Si04] shares 3 O2-, forming planar layers with [Si4010] complex anions (Si:O=4:10)", "B": "[Si04] shares 2 O2-, forming chain structures with [Si306] complex anions (Si:O=3:9)", "C": "[Si04] shares 4 O2-, forming 3D frameworks with [SiO2] complex anions (Si:O=1:2)", "D": "[Si04] shares 1 O2-, forming isolated tetrahedra with [SiO4] complex anions (Si:O=1:4)" }, "correct_answer": "A", "explanation": "Correct answer A describes the unique 2D sheet structure where each [SiO4] shares 3 oxygen atoms. B mimics chain silicates, C mimics quartz structure, and D mimics orthosilicates - all common but wrong structural analogs. The key is recognizing the specific 4:10 ratio and planar [Si4010] sheets unique to layered silicates.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2778, "question": "At a temperature of 1223K, calculate the diffusion coefficient of interstitial atoms in a face-centered cubic metal. The thickness of the metal film is 0.25mm, the end face area is 1000mm², the rate of interstitial atoms passing through the film is 0.0025g/s, and the solubility of interstitial atoms in the film is 14.4kg/m³.", "answer": "According to Fick's first law, the formula for calculating the diffusion coefficient D is: D = -J * Δx / Δρ. Here, J = v / A = 0.0025g/s / 1000mm² = 0.0025×10⁻³kg/s / 10⁻³m² = 0.0025kg/(m²·s). Δx = 0.25mm = 0.25×10⁻³m. Δρ = 0 - 14.4kg/m³ = -14.4kg/m³. Therefore, D = -0.0025kg/(m²·s) * 0.25×10⁻³m / (-14.4kg/m³) ≈ 4.34×10⁻⁸m²/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解扩散系数，答案展示了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目主要涉及Fick第一定律的直接应用和简单计算，不需要多步推理或综合分析，属于基本公式的直接套用和数值计算。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用Fick第一定律公式，但解题步骤相对直接，仅需进行单位转换和简单代数运算。题目提供了所有必要参数，且计算过程不涉及复杂推导或多步骤分析，符合选择题型中\"简单公式应用计算\"的特征。", "convertible": true, "correct_option": "4.34×10⁻⁸m²/s", "choice_question": "At a temperature of 1223K, the diffusion coefficient of interstitial atoms in a face-centered cubic metal is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.34×10⁻⁸m²/s", "B": "2.17×10⁻⁸m²/s", "C": "8.68×10⁻⁸m²/s", "D": "1.73×10⁻⁷m²/s" }, "correct_answer": "A", "explanation": "The correct answer A is derived from the steady-state diffusion solution using Fick's first law, where the diffusion coefficient D = (rate × thickness)/(area × concentration gradient). Option B is a common error from incorrectly halving the concentration gradient. Option C results from doubling the film thickness in calculations. Option D comes from confusing the temperature dependence of diffusion coefficients with Arrhenius equation pre-exponential factors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3359, "question": "Classify according to the interaction between alloying elements and carbon, and indicate which elements do not form carbides", "answer": "Non-carbide forming elements: nickel, silicon, cobalt, aluminum, copper, boron, nitrogen, etc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对合金元素与碳的相互作用进行分类，并列举不形成碳化物的元素，这需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对合金元素与碳相互作用分类的基础概念记忆，以及非碳化物形成元素的列举，属于基础概念的记忆和理解层面。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别并回忆非碳化物形成元素的列表。题目直接给出了正确选项，无需进行复杂的概念比较或推理分析，符合等级1“基本定义简答”的标准。", "convertible": true, "correct_option": "nickel, silicon, cobalt, aluminum, copper, boron, nitrogen", "choice_question": "Which of the following elements do not form carbides?", "conversion_reason": "The answer is a standard list of elements, which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ni, Co, Cu", "B": "Si, B, N", "C": "Al, Ti, V", "D": "Cr, W, Mo" }, "correct_answer": "A", "explanation": "Correct answer is A because nickel (Ni), cobalt (Co), and copper (Cu) are transition metals that do not form stable carbides due to their electronic configurations and low carbon affinity. Option B is a trap using elements that actually form carbides (B, Si) or nitrides (N). Option C exploits the common misconception that all light metals (Al) don't form carbides, while including actual carbide formers (Ti, V). Option D lists classic strong carbide formers to test if the AI recognizes the opposite pattern.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3241, "question": "The driving force for atomic diffusion is A. Concentration gradient of components B. Temperature gradient C. Chemical potential gradient of components", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案 | 知识层次: 题目考查对原子扩散驱动力的基本概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然考查的是基础概念记忆，但需要学生对\"原子扩散驱动力\"这一概念有准确理解，并能区分浓度梯度、温度梯度和化学势梯度这三个相近概念。正确选项C不是最直观的选项(学生可能首先想到浓度梯度)，因此需要一定的概念辨析能力，但不需要复杂的分析过程。", "convertible": true, "correct_option": "Chemical potential gradient of components", "choice_question": "The driving force for atomic diffusion is", "conversion_reason": "The original question is already in a single-choice format with a clear correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Concentration gradient of components", "B": "Temperature gradient", "C": "Chemical potential gradient of components", "D": "Electrochemical potential gradient" }, "correct_answer": "C", "explanation": "The correct answer is C because atomic diffusion is fundamentally driven by the chemical potential gradient, which accounts for both concentration and other thermodynamic factors. Option A is a strong distractor as it exploits the common misconception that concentration gradient alone drives diffusion (Fick's first law surface-level interpretation). Option B targets confusion with heat transfer mechanisms. Option D introduces a sophisticated but contextually incorrect concept (electrochemical potential applies to charged species in electric fields). The question requires distinguishing between phenomenological laws and fundamental driving forces in non-equilibrium thermodynamics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1864, "question": "Briefly describe the crystallographic characteristics of martensitic transformation.", "answer": "The crystallographic characteristics of martensitic transformation include: a strict orientation relationship between the new phase and the parent phase during the transformation, maintenance of a coherent relationship through shear, the presence of a habit plane that remains undistorted and unrotated before and after the transformation, and macroscopic continuity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要描述马氏体相变的晶体学特征，答案以文字解释和论述的形式呈现，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求描述马氏体相变的晶体学特征，涉及多个复杂概念的关联和综合分析，包括新相与母相的取向关系、剪切保持的相干关系、习惯面的不变性以及宏观连续性等。这需要深入理解相变机理和晶体学原理，并进行推理分析，属于较高层次的认知要求。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生综合运用多个复杂概念（如取向关系、共格关系、惯习面等），并理解马氏体相变的晶体学机理。正确选项涉及对相变过程中微观结构和宏观现象的全面分析，需要考生具备深度推理和机理解释能力。这种综合性的知识运用和复杂现象分析在选择题中属于最高难度水平。", "convertible": true, "correct_option": "a strict orientation relationship between the new phase and the parent phase during the transformation, maintenance of a coherent relationship through shear, the presence of a habit plane that remains undistorted and unrotated before and after the transformation, and macroscopic continuity", "choice_question": "Which of the following describes the crystallographic characteristics of martensitic transformation?", "conversion_reason": "The answer is a standard description of the crystallographic characteristics of martensitic transformation, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A strict orientation relationship between phases maintained through shear deformation, with an invariant habit plane", "B": "Random nucleation of new phase with isotropic growth, accompanied by significant volume diffusion", "C": "Complete loss of crystallographic registry, resulting in polycrystalline microstructure with high angle grain boundaries", "D": "Gradual lattice rotation through dislocation climb, preserving the original crystal symmetry" }, "correct_answer": "A", "explanation": "Correct answer A describes the key features of martensitic transformation: strict orientation relationship, shear mechanism, and invariant habit plane. Option B incorrectly describes diffusional transformation characteristics. Option C describes complete recrystallization, not martensite. Option D describes creep deformation, not phase transformation. The traps exploit: 1) confusion between diffusionless vs diffusional transformations (B), 2) mixing recrystallization concepts (C), and 3) borrowing dislocation mechanisms from deformation processes (D).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3945, "question": "If [m] atoms of helium pass through a [a] square meter plate area every [t] hours, and if this flux is constant with time, compute the flux of helium in units of atoms per square meter per second.", "answer": "\\[\nj = \\frac{[m]}{[a] × [t] × 3600} \\text{ atoms per square meter per second}\n\\]", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，以求得氦的通量，答案给出了具体的计算公式和单位转换步骤。 | 知识层次: 题目要求将给定的物理量（原子数、面积、时间）通过基本公式转换为特定单位（原子/平方米/秒）的流量，属于直接套用单位换算公式的简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用一个简单的公式进行计算，即通过给定的原子数量、面积和时间，转换为每秒每平方米的原子通量。解题步骤非常直接，不涉及多个公式的组合或复杂的逻辑推理，符合等级1的单一公式直接计算标准。", "convertible": true, "correct_option": "j = [m]/([a] × [t] × 3600) atoms per square meter per second", "choice_question": "If [m] atoms of helium pass through a [a] square meter plate area every [t] hours, and if this flux is constant with time, what is the flux of helium in units of atoms per square meter per second?", "conversion_reason": "The calculation problem has a specific and deterministic answer, making it suitable for conversion into a multiple-choice question format. The correct option can be directly derived from the given formula.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "j = [m]/([a] × [t] × 3600) atoms per square meter per second", "B": "j = [m] × [a] × [t]/3600 atoms per square meter per second", "C": "j = [m]/([a] × [t]) atoms per square meter per second", "D": "j = [m] × 3600/([a] × [t]) atoms per square meter per second" }, "correct_answer": "A", "explanation": "The correct answer A properly accounts for all variables and unit conversions (hours to seconds). Option B reverses the numerator and denominator relationship, a common algebraic error. Option C neglects the crucial time unit conversion from hours to seconds, exploiting cognitive bias toward simpler expressions. Option D incorrectly multiplies by 3600 instead of dividing, targeting intuition about time unit conversions but reversing the operation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2866, "question": "A factory used a cold-drawn steel wire rope to lift a large steel component into a heat treatment furnace. Due to a momentary oversight, the wire rope was not removed but was heated together with the component to $860~\\\\mathrm{{^\\\\circC}}$. When the holding time was reached and the furnace door was opened to lift out the component, the wire rope broke. Analyze the cause.", "answer": "The cold-drawn steel wire rope is made by twisting cold-drawn steel wires with large deformation. The cold work hardening during the processing significantly improves the strength and hardness of the steel wires, enabling them to bear heavy loads. However, when heated to ${\\\\tt860^{\\\\circ}C}$, the temperature far exceeds the recrystallization temperature of the wire rope, leading to recovery and recrystallization phenomena. The effect of work hardening completely disappears, and the strength and hardness are greatly reduced. When used for lifting again, once the load exceeds its bearing capacity, it inevitably leads to the fracture of the wire rope.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析钢丝绳断裂的原因，答案通过文字解释和论述的方式详细说明了冷拔钢丝绳在高温下发生的微观结构变化及其对力学性能的影响，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求分析冷拔钢丝绳在高温下断裂的原因，涉及冷加工硬化、回复与再结晶等复杂材料科学原理的综合运用和推理分析。需要理解冷加工硬化对材料性能的影响，以及高温下回复和再结晶过程如何消除加工硬化效应，导致材料性能下降。这需要较深层次的材料科学知识和对材料行为机理的理解，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The cold-drawn steel wire rope is made by twisting cold-drawn steel wires with large deformation. The cold work hardening during the processing significantly improves the strength and hardness of the steel wires, enabling them to bear heavy loads. However, when heated to ${\\tt860^{\\circ}C}$, the temperature far exceeds the recrystallization temperature of the wire rope, leading to recovery and recrystallization phenomena. The effect of work hardening completely disappears, and the strength and hardness are greatly reduced. When used for lifting again, once the load exceeds its bearing capacity, it inevitably leads to the fracture of the wire rope.", "choice_question": "A factory used a cold-drawn steel wire rope to lift a large steel component into a heat treatment furnace. Due to a momentary oversight, the wire rope was not removed but was heated together with the component to $860~\\mathrm{{^\\circC}}$. When the holding time was reached and the furnace door was opened to lift out the component, the wire rope broke. What is the cause of the wire rope breaking?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the cause of the wire rope breaking.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The high temperature caused oxidation-induced embrittlement of the steel wire surface", "B": "The heating process eliminated the cold work hardening effect through recrystallization", "C": "The thermal expansion mismatch between the wire rope and the component created excessive stress", "D": "The austenitization temperature altered the wire's crystal structure, reducing its yield strength" }, "correct_answer": "B", "explanation": "The correct answer is B because cold-drawn steel's strength comes from work hardening, which is eliminated by recrystallization at 860°C. Option A is a cognitive bias trap - while oxidation occurs, it's not the primary failure mechanism. Option C exploits intuition about thermal stresses but ignores the fundamental material change. Option D contains partially correct information about austenitization but misattributes the primary failure cause.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2439, "question": "For a face-centered cubic crystal stretched along the [131] axis, determine the resolved shear stress on the slip system (111)[0-11]. The tensile stress is 6.9×10^5 Pa.", "answer": "According to the relationship between tensile stress and resolved shear stress on the slip system, τ=σcosλcosφ. For the slip system (111)[0-11], the cosine of the angle between [131] and the slip plane normal [111], cosφ, and the cosine of the angle between [131] and the slip direction [0-11], cosλ, are: cosφ=(1×1 + 3×1 + 1×1)/(√(1+1+1)×√(1+9+1))=5/(√3×√11)=0.870; cosλ=(1×0 + 3×(-1) + 1×1)/(√(1+9+1)×√(0+1+1))=-2/(√11×√2)=-0.426. The resolved shear stress τ=6.9×10^5×0.870×(-0.426) Pa=-2.56×10^5 Pa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（如τ=σcosλcosφ）来确定分解剪应力，答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目需要多步计算（包括角度余弦计算和应力分解），涉及晶体几何和力学概念的关联应用，需要综合分析拉伸方向、滑移面和滑移方向之间的关系。虽然不涉及创新或深度机理分析，但计算过程较为复杂，超出了简单套用公式的范畴。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如晶体学方向指数、滑移系统、分切应力公式）并进行多步计算（包括方向余弦计算和应力转换）。虽然题目提供了具体步骤，但要求考生具备较强的空间几何想象力和综合计算能力，属于需要综合分析的应用题。", "convertible": true, "correct_option": "-2.56×10^5 Pa", "choice_question": "For a face-centered cubic crystal stretched along the [131] axis, the resolved shear stress on the slip system (111)[0-11] under a tensile stress of 6.9×10^5 Pa is:", "conversion_reason": "The original calculation question has a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-2.56×10^5 Pa", "B": "3.82×10^5 Pa", "C": "1.73×10^5 Pa", "D": "5.12×10^5 Pa" }, "correct_answer": "A", "explanation": "The correct answer is A (-2.56×10^5 Pa) calculated using the resolved shear stress formula considering the correct slip plane normal and slip direction vectors. Option B (3.82×10^5 Pa) is a common error from incorrectly using the Schmid factor for a different slip system. Option C (1.73×10^5 Pa) results from miscalculating the angle between tensile axis and slip direction. Option D (5.12×10^5 Pa) is a trap for those who forget to include the negative sign indicating opposite shear directions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 194, "question": "At $20^{\\\\circ}\\\\mathrm{C}$, the interfacial tensions of ether-water, mercury-ether, and mercury-water are 0.0107, 0.379, and 0.375 N/m, respectively. A drop of water is placed on the interface between ether and mercury. Find the contact angle.", "answer": "$$\\\\cos\\\\theta=\\\\frac{\\\\gamma_{s v}-\\\\gamma_{s l}}{\\\\gamma_{l v}}=\\\\frac{0.379-0.375}{0.0107}=0.3738.\\\\theta=68.0498^{\\\\circ}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的界面张力数据，应用公式计算接触角，答案是一个具体的数值计算结果，符合计算题的特征。 | 知识层次: 题目主要考查基本公式的应用和简单计算，涉及界面张力的概念和接触角公式的直接套用，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目直接给出了所需的界面张力数据，并明确要求使用接触角的基本公式进行计算。解题步骤仅涉及将给定数值代入公式并进行简单的除法运算，无需复杂的推导或多步骤分析。虽然需要理解界面张力和接触角的基本概念，但在选择题型中，这种直接套用公式的题目相对简单，属于等级2难度。", "convertible": true, "correct_option": "68.0498°", "choice_question": "At $20^{\\circ}\\mathrm{C}$, the interfacial tensions of ether-water, mercury-ether, and mercury-water are 0.0107, 0.379, and 0.375 N/m, respectively. A drop of water is placed on the interface between ether and mercury. What is the contact angle?", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format with the correct option being the calculated angle.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "68.0498°", "B": "112.345°", "C": "45.000°", "D": "151.231°" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Young's equation for interfacial tensions: θ = arccos((γ_mercury-ether - γ_mercury-water)/γ_ether-water). Option B is a common error from misapplying the cosine function. Option C exploits the tendency to assume 45° for symmetric systems. Option D is the supplementary angle trap, exploiting confusion between contact angle and its supplement.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3353, "question": "Suppose the microstructure of a certain alloy consists of spherical second-phase particles and a matrix. If the actual diameters of the second-phase particles are all equal, how should the particle size be determined under a metallographic microscope?", "answer": "Measure the diameter of the largest particle.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释和论述来说明如何确定粒子尺寸，而不是从选项中选择、判断对错或进行数值计算。 | 知识层次: 题目考查对金相显微镜下测量第二相粒子尺寸的基本方法的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即测量第二相颗粒直径的基本方法。正确选项直接给出了明确的答案，无需复杂推理或概念比较，属于最基础的定义简答级别。", "convertible": true, "correct_option": "Measure the diameter of the largest particle", "choice_question": "Suppose the microstructure of a certain alloy consists of spherical second-phase particles and a matrix. If the actual diameters of the second-phase particles are all equal, how should the particle size be determined under a metallographic microscope?", "conversion_reason": "The answer is a standard procedure or method, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Measure the diameter of the largest particle", "B": "Calculate the average diameter of all visible particles", "C": "Measure the diameter where the particle intersects the focal plane", "D": "Use the smallest visible particle diameter as reference" }, "correct_answer": "A", "explanation": "The correct answer is A because in metallography, spherical particles appear as circles of varying diameters depending on their position relative to the sectioning plane. Only the largest observed diameter represents the true particle size. Option B is incorrect because averaging would underestimate the true size. Option C exploits the common microscopy intuition but is wrong for spherical particles. Option D is a reversal trap exploiting the opposite intuition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 382, "question": "Coincidence site lattice", "answer": "Consider two identical and coinciding lattices $L_{1}$ and $L_{2}$. After rotating or translating $L_{2}$ relative to $L_{1}$, the lattices formed by the coinciding positions of the two lattices constitute a new periodic superlattice.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Coincidence site lattice\"进行文字解释和论述，答案提供了概念性的描述和定义，属于简答题类型 | 知识层次: 题目考查对Coincidence site lattice（重合位置点阵）这一基本概念的定义和基本原理的记忆和理解，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要理解并描述两个晶格重合后形成超晶格的过程，这比简单的定义记忆要复杂一些。题目要求考生能够解释和描述这一现象，而不仅仅是回忆定义，因此属于等级2。", "convertible": true, "correct_option": "Consider two identical and coinciding lattices $L_{1}$ and $L_{2}$. After rotating or translating $L_{2}$ relative to $L_{1}$, the lattices formed by the coinciding positions of the two lattices constitute a new periodic superlattice.", "choice_question": "下列关于Coincidence site lattice的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Consider two identical and coinciding lattices $L_{1}$ and $L_{2}$. After rotating or translating $L_{2}$ relative to $L_{1}$, the lattices formed by the coinciding positions of the two lattices constitute a new periodic superlattice.", "B": "Coincidence site lattice is formed when two identical lattices are superimposed without any rotation or translation, resulting in perfect atomic registry.", "C": "The coincidence site lattice represents the common periodic structure formed by the intersection of two identical lattices after one undergoes a specific rotation that creates a rational fraction of coinciding sites.", "D": "Coincidence site lattice is a non-periodic arrangement that occurs when two dissimilar lattices are superimposed at arbitrary angles, creating a quasicrystalline pattern." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines CSL as a periodic superlattice formed by coinciding positions after relative rotation/translation of identical lattices. Option B is incorrect because it eliminates the essential rotation/translation requirement. Option C is a subtle trap - while mentioning rotation, it incorrectly implies only rational fractions create CSL. Option D exploits confusion with quasicrystals by suggesting non-periodicity, which contradicts CSL's fundamental periodic nature.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4125, "question": "Do carbon-carbon composites exhibit low coefficients of thermal expansion?", "answer": "Carbon-carbon composites have low coefficients of thermal expansion.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（碳-碳复合材料是否具有低热膨胀系数），答案直接给出了对陈述的判断（是/否）。这符合判断题的特征。 | 知识层次: 题目考查对碳碳复合材料基本特性的记忆和理解，属于基础概念层次。 | 难度: 在选择题型内，该题目仅涉及基础概念记忆，即碳碳复合材料的热膨胀系数特性。正确选项直接陈述了定义性知识，无需复杂理解或分析。属于最基础的正误判断，符合等级1的难度标准。", "convertible": true, "correct_option": "Carbon-carbon composites have low coefficients of thermal expansion.", "choice_question": "Do carbon-carbon composites exhibit low coefficients of thermal expansion?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All carbon-carbon composites exhibit coefficients of thermal expansion below 1×10^-6/K at all temperatures.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While carbon-carbon composites generally have low CTE values (typically 0.5-4×10^-6/K), this absolute statement is incorrect because: 1) CTE values vary with fiber architecture and processing conditions, 2) some orientations may exceed this threshold, 3) temperature dependence exists (CTE may increase at elevated temperatures), and 4) exact values depend on measurement conditions. The absolute claim fails to account for these variations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3161, "question": "What type of alloy phase is VC, and what are its structural characteristics?", "answer": "VC is an interstitial phase, where V occupies the lattice points of a face-centered cubic lattice, and C occupies all the octahedral interstitial sites. It belongs to the face-centered cubic lattice and has a NaCl-type structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释VC合金相的类型和结构特征，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查对合金相类型和结构特征的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（合金相类型和结构特征），但需要考生准确记忆并描述VC的具体结构特征（间隙相、面心立方晶格、NaCl型结构）。这比单纯识别合金相类型（等级1）要求更高的概念解释和描述能力，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "VC is an interstitial phase, where V occupies the lattice points of a face-centered cubic lattice, and C occupies all the octahedral interstitial sites. It belongs to the face-centered cubic lattice and has a NaCl-type structure.", "choice_question": "Which of the following correctly describes the type of alloy phase VC and its structural characteristics?", "conversion_reason": "The answer is a standard description of the alloy phase VC and its structural characteristics, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "VC is an interstitial phase with V in FCC lattice and C occupying all octahedral sites, forming NaCl-type structure", "B": "VC is a substitutional solid solution where C atoms randomly replace V atoms in a BCC lattice", "C": "VC is an intermetallic compound with ordered CsCl-type structure where V and C occupy alternate cube corners", "D": "VC is an interstitial compound with hexagonal close-packed structure where C occupies tetrahedral voids" }, "correct_answer": "A", "explanation": "The correct answer is A because VC indeed forms an interstitial phase with vanadium atoms forming an FCC lattice and carbon occupying all octahedral interstitial sites, creating a NaCl-type structure. Option B is wrong but tempting because it uses the common misconception of substitutional solutions in BCC structures. Option C is deceptive as it describes a real CsCl-type structure but applies it to the wrong material system. Option D exploits the common association of interstitial compounds with HCP structures, which is incorrect for VC.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4309, "question": "Give the approximate temperature at which creep deformation becomes an important consideration for aluminum.", "answer": "for al: 100 degrees c (212 degrees f)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从多个选项中选择或判断对错，也不需要复杂的计算过程。答案是一个简短的具体数值，符合简答题的特征。 | 知识层次: 题目考查对铝材料蠕变变形温度的基本概念记忆，不需要复杂的应用或分析，只需记住特定温度值即可。 | 难度: 在选择题型中，该题目仅要求记忆铝的蠕变变形重要温度这一基础知识点，属于基本定义简答级别。不需要解释或分析，只需直接回忆具体数值即可作答。", "convertible": true, "correct_option": "100 degrees C (212 degrees F)", "choice_question": "At approximately what temperature does creep deformation become an important consideration for aluminum?", "conversion_reason": "The answer is a specific temperature value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "100°C (212°F)", "B": "0.4 times the melting point (≈200°C)", "C": "Room temperature (25°C)", "D": "Recrystallization temperature (≈150°C)" }, "correct_answer": "A", "explanation": "The correct answer is A because creep becomes significant for aluminum at about 100°C, which is approximately 0.3 of its melting point. Option B is a trap for those who know the '0.4 rule' but don't realize it applies to steels, not aluminum. Option C exploits the common misconception that creep only occurs at high temperatures. Option D uses a related but irrelevant material property (recrystallization temp) to mislead.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4275, "question": "Define a slip system.", "answer": "A slip system is a crystallographic plane, and, within that plane, a direction along which dislocation motion (or slip) occurs.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"slip system\"进行定义和解释，需要提供文字论述而非选择、判断或计算 | 知识层次: 题目考查对\"slip system\"这一基本概念的定义记忆和理解，属于材料科学中晶体缺陷和塑性变形的基础知识范畴，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并复述\"slip system\"的基本定义，属于最基础的概念性知识。题目不涉及任何解释、比较或应用层面的要求，完全符合等级1\"基本定义简答\"的标准。选择题型中此类直接考查定义的题目通常难度最低，只需简单记忆即可作答。", "convertible": true, "correct_option": "A slip system is a crystallographic plane, and, within that plane, a direction along which dislocation motion (or slip) occurs.", "choice_question": "Which of the following best defines a slip system?", "conversion_reason": "The answer is a standard definition of a slip system, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A slip system is a crystallographic plane, and, within that plane, a direction along which dislocation motion (or slip) occurs.", "B": "A slip system refers to the combination of a Burgers vector and a line direction of dislocation in a crystal lattice.", "C": "A slip system is defined by the maximum resolved shear stress direction in a polycrystalline material under load.", "D": "A slip system represents the atomic density difference between two adjacent crystallographic planes in a deformed material." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a slip system as the combination of a crystallographic plane and a slip direction within that plane, which is the fundamental definition in materials science. Option B incorrectly confuses slip systems with dislocation line characteristics. Option C misleadingly associates slip systems with stress conditions rather than crystallography. Option D introduces an unrelated concept of atomic density differences, creating a surface-level plausible but fundamentally wrong definition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4576, "question": "Define the term 'extrinsic' as it pertains to semiconducting materials and provide an example.", "answer": "extrinsic--P-doped Ge, B-doped Si, S-doped GaP, etc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求定义术语并提供例子，需要文字解释和论述 | 知识层次: 题目考查对\"extrinsic\"这一基本术语的定义记忆，以及通过举例说明的理解能力，属于半导体材料的基础概念范畴。 | 难度: 在选择题型中，该题目仅要求记忆并选择\"extrinsic\"的定义和相关示例（如P-doped Ge等），属于基础概念记忆层次。题目不涉及解释或复杂概念体系，只需识别正确选项即可，因此属于最简单的等级1难度。", "convertible": true, "correct_option": "extrinsic--P-doped Ge, B-doped Si, S-doped GaP, etc.", "choice_question": "Which of the following correctly defines the term 'extrinsic' as it pertains to semiconducting materials and provides an example?", "conversion_reason": "The answer is a standard definition with examples, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Extrinsic semiconductors contain intentional dopant atoms that alter electrical properties, e.g. P-doped Ge", "B": "Extrinsic refers to surface defects in semiconductors that influence conductivity, e.g. oxidized Si surfaces", "C": "Extrinsic denotes temperature-dependent conductivity changes in pure semiconductors, e.g. undoped Si at high temperatures", "D": "Extrinsic describes the natural impurity levels in as-grown semiconductor crystals, e.g. trace carbon in GaAs" }, "correct_answer": "A", "explanation": "The correct answer is A because extrinsic semiconductors are defined by deliberate doping with foreign atoms to modify electrical properties. Option B exploits surface science confusion, Option C describes intrinsic behavior, and Option D targets confusion between intentional doping and unintentional impurities. Advanced AI might select B due to 'surface' being a common extrinsic factor in materials, or D by misinterpreting 'extrinsic' as any impurity.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3242, "question": "When polycrystalline metal is heated to a relatively high temperature and held, the grains will grow. The grain growth mode is A. Subgrain coalescence and growth B. Grain boundary bowing outward and growth C. Grain boundary moving toward the curvature center D. Movement of Y junctions", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从选项A、B、C、D中选择一个正确答案，符合选择题的特征。 | 知识层次: 题目考查对晶粒生长模式的理解，需要将晶界移动与曲率中心的关系进行综合分析，属于中等应用层次。 | 难度: 在选择题型中，此题属于较高难度。题目涉及多晶金属在高温下的晶粒生长机制，需要考生理解晶界移动的物理机制（如曲率驱动迁移）并综合分析不同生长模式的区别。正确选项C要求考生掌握晶界向曲率中心移动这一非直观概念，并能排除其他看似合理的干扰选项（如亚晶合并或Y结移动）。这需要将材料科学基础理论与实际现象关联，属于中等应用层次的多步分析判断。", "convertible": true, "correct_option": "C. Grain boundary moving toward the curvature center", "choice_question": "When polycrystalline metal is heated to a relatively high temperature and held, the grains will grow. The grain growth mode is:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a standard single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dislocation climb controlled by vacancy diffusion", "B": "Grain boundary migration driven by surface energy minimization", "C": "Atomic shuffling through coordinated shear transformations", "D": "Collective rearrangement of atoms via liquid-like interfaces" }, "correct_answer": "B", "explanation": "The correct answer is B because grain growth in polycrystalline metals at high temperatures is primarily driven by grain boundary migration to minimize total grain boundary energy. Option A describes creep deformation mechanism, not grain growth. Option C describes martensitic transformation mechanism. Option D describes grain boundary sliding or superplastic deformation mechanisms. These incorrect options exploit AI's tendency to confuse related but distinct materials phenomena and overcomplicate the physical process.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 889, "question": "Determine whether the following dislocation reaction can proceed in FCC and confirm the reaction direction in the absence of external forces: 1/3[112]+1/2[111]⇔1/6[11−1]", "answer": "The reaction cannot proceed.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断位错反应是否能进行，并给出明确结论（\"The reaction cannot proceed\"），这符合判断题的特征，即判断陈述的对错。 | 知识层次: 题目需要理解位错反应的基本原理，并能够应用这些原理来判断反应是否可行。虽然不涉及复杂的计算，但需要对FCC晶体结构中的位错类型和反应方向有较深入的理解，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。需要综合运用位错反应的能量条件（Frank判据）和晶体学知识进行多步计算和判断。解题过程涉及矢量运算、能量比较和反应方向分析，属于需要综合分析结果判断的类型。虽然题目提供了反应式，但需要考生自行验证反应前后的能量变化和晶体学可行性，比单纯的概念识别或简单计算题更复杂。", "convertible": true, "correct_option": "The reaction cannot proceed.", "choice_question": "Determine whether the following dislocation reaction can proceed in FCC and confirm the reaction direction in the absence of external forces: 1/3[112]+1/2[111]⇔1/6[11−1]", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In FCC crystals, the dislocation reaction 1/3[112] + 1/2[111] ⇔ 1/6[11−1] can proceed spontaneously in the absence of external forces due to the reduction in total Burgers vector magnitude.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This reaction cannot proceed because: 1) The left side Burgers vector sum (1/3[112] + 1/2[111] = [7/6, 7/6, 1/6]) doesn't equal the right side (1/6[11−1] = [1/6, 1/6, -1/6]), violating conservation of Burgers vector. 2) The energy criterion isn't satisfied as the magnitude of the left side (√(2*(7/6)^2 + (1/6)^2) ≈ 1.68) is greater than the right side (√(2*(1/6)^2 + (1/6)^2) ≈ 0.41). Common mistakes include overlooking Burgers vector conservation or miscalculating the energy balance.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2204, "question": "Pure zirconium requires 40 h and 1 h of isothermal annealing at $553^{\\\\circ}\\\\mathrm{C}$ and $627^{\\\\circ}\\\\mathrm{C}$ respectively to complete recrystallization. Calculate the recrystallization activation energy of this material.", "answer": "From Equation (7-6) in Section 7.3: $$Therefore$$ Q=R\\\\ln\\\\frac{t_{1}}{t_{2}}\\\\bigg/\\\\Big(\\\\frac{1}{T_{1}}-\\\\frac{1}{T_{2}}\\\\Big)$$ Substituting the known values, we get $$ Q={\\\\frac{8.31\\\\ln{\\\\frac{40}{1}}}{{\\\\frac{1}{553+273}}-{\\\\frac{1}{627+273}}}}=3.08\\\\times10^{5}~\\\\mathrm{J/mol}$$ \\\\ln{\\\\frac{t_{1}}{t_{2}}}=\\\\frac{Q}{R}\\\\Big(\\\\frac{1}{T_{1}}-\\\\frac{1}{T_{2}}\\\\Big)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解再结晶活化能，答案中包含了具体的计算步骤和公式应用，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括公式的变形和数值代入，同时需要理解再结晶激活能的概念及其与温度和时间的关系。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力和概念关联。 | 难度: 在选择题中属于中等偏上难度，需要理解再结晶激活能的概念，掌握Arrhenius方程的应用，并进行多步骤的计算。题目涉及温度转换（摄氏到开尔文）、对数运算和单位换算，虽然计算过程明确，但步骤较多且需要准确执行。", "convertible": true, "correct_option": "3.08×10^5 J/mol", "choice_question": "Pure zirconium requires 40 h and 1 h of isothermal annealing at 553°C and 627°C respectively to complete recrystallization. The recrystallization activation energy of this material is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.08×10^5 J/mol", "B": "2.45×10^5 J/mol", "C": "1.86×10^5 J/mol", "D": "4.12×10^5 J/mol" }, "correct_answer": "A", "explanation": "正确答案A是通过Arrhenius方程精确计算得出的纯锆再结晶激活能。干扰项B利用了常见金属激活能范围(2-3×10^5 J/mol)的直觉判断陷阱；干扰项C基于错误使用自然对数与常用对数的换算关系；干扰项D则通过温度倒数计算时故意混淆开尔文与摄氏温度单位。这些干扰项都针对AI在单位换算和材料特性范围判断上的潜在弱点。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3360, "question": "When hypereutectoid steel is slowly cooled from the austenite region, secondary cementite will precipitate along the austenite grain boundaries in a network form. How can the network cementite be eliminated by heating above Ac cm followed by air cooling and subsequent treatment?", "answer": "Heating above Ac cm followed by air cooling to obtain a pseudo-eutectoid structure, then performing high-temperature tempering or spheroidizing annealing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案提供了详细的处理步骤和后续处理方法，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目需要理解过共析钢的冷却过程及二次渗碳体的形成机制，并应用热处理工艺（加热至Ac cm以上、空冷、高温回火或球化退火）来消除网状渗碳体。这涉及多步操作和概念关联，但不需要复杂的推理或创新设计。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目涉及多个热处理步骤的综合应用，包括加热、冷却和后续处理，需要考生对每个步骤的作用和相互关系有深入理解。其次，正确选项要求考生能够将伪共析组织形成原理与高温回火或球化退火工艺联系起来，这需要较强的概念关联能力。此外，题目考察的是对网络状渗碳体消除方法的综合分析能力，而非单一知识点的简单记忆，在选择题型中属于需要多角度分析论述的复杂题目。", "convertible": true, "correct_option": "Heating above Ac cm followed by air cooling to obtain a pseudo-eutectoid structure, then performing high-temperature tempering or spheroidizing annealing.", "choice_question": "How can the network cementite in hypereutectoid steel be eliminated by heating above Ac cm followed by air cooling and subsequent treatment?", "conversion_reason": "The answer is a standard procedure and can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Heating above Ac cm followed by air cooling to obtain a pseudo-eutectoid structure, then performing high-temperature tempering or spheroidizing annealing", "B": "Heating above Ac cm followed by rapid quenching to form martensite, then performing low-temperature tempering", "C": "Heating just below Ac cm followed by slow cooling to promote complete spheroidization of cementite", "D": "Heating above Ac cm followed by controlled cooling at 50°C/hour to prevent network cementite formation" }, "correct_answer": "A", "explanation": "The correct answer is A because heating above Ac cm dissolves the network cementite, air cooling creates a pseudo-eutectoid structure that avoids grain boundary precipitation, and subsequent tempering/spheroidizing ensures cementite forms as discrete particles. Option B is incorrect because quenching would form martensite but not address the network cementite issue. Option C is wrong as heating below Ac cm cannot dissolve existing network cementite. Option D is incorrect because controlled cooling alone cannot prevent network cementite formation in hypereutectoid steels.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 952, "question": "Briefly describe the crystallization process of steel with a carbon content of 0.25%", "answer": "The liquid phase first solidifies into ferrite, and a peritectic reaction occurs at 1495°C to form γ-austenite; upon further cooling, the remaining liquid phase precipitates γ-austenite again, which then transforms into single-phase austenite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求简要描述钢的结晶过程，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求描述钢的结晶过程，涉及相变反应和温度变化，需要理解并关联多个概念（如铁素体、奥氏体、包晶反应等），并进行综合分析。虽然不涉及复杂计算，但需要对相图和相关转变有较深的理解和应用能力。 | 难度: 在选择题中属于中等难度，需要理解钢的结晶过程、相变反应（如包晶反应）以及不同温度下的相组成变化。虽然题目提供了具体的碳含量和温度信息，但解题者仍需综合运用相图知识和相变原理来分析结晶过程，涉及多步概念关联和综合分析。", "convertible": true, "correct_option": "The liquid phase first solidifies into ferrite, and a peritectic reaction occurs at 1495°C to form γ-austenite; upon further cooling, the remaining liquid phase precipitates γ-austenite again, which then transforms into single-phase austenite.", "choice_question": "Which of the following correctly describes the crystallization process of steel with a carbon content of 0.25%?", "conversion_reason": "The answer is a standard description of a process, which can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The liquid phase first solidifies into ferrite, and a peritectic reaction occurs at 1495°C to form γ-austenite; upon further cooling, the remaining liquid phase precipitates γ-austenite again, which then transforms into single-phase austenite.", "B": "The liquid phase directly transforms into austenite at 1495°C through a peritectic reaction, followed by complete solidification into single-phase austenite without intermediate ferrite formation.", "C": "The liquid phase first forms δ-ferrite, then undergoes a eutectic reaction at 1148°C to produce a mixture of austenite and cementite.", "D": "The liquid phase solidifies into austenite through a continuous cooling transformation, bypassing all peritectic reactions due to the low carbon content." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the crystallization process of 0.25% carbon steel: initial ferrite formation, peritectic reaction at 1495°C, and final austenite transformation. Option B incorrectly skips the initial ferrite formation. Option C wrongly introduces a eutectic reaction which doesn't occur at this carbon content. Option D falsely suggests continuous transformation, ignoring the mandatory peritectic reaction in this steel composition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1084, "question": "Are the shapes of the room-temperature tensile curves of low-carbon steel and aluminum alloy the same?", "answer": "The shapes of the room-temperature tensile curves of low-carbon steel and aluminum alloy are not the same.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断陈述的对错（低碳钢和铝合金的室温拉伸曲线形状是否相同），答案直接给出了明确的判断结果（不相同），符合判断题的特征。 | 知识层次: 题目考查对低合金钢和铝合金室温拉伸曲线形状差异的基本概念记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度等级。题目要求考生比较低碳钢和铝合金的室温拉伸曲线形状是否相同，这需要考生掌握两种材料的基本拉伸行为特征，属于对基础概念的对比理解。虽然需要记忆两种材料的特性，但不需要复杂的分析或推理过程，因此属于中等偏下的难度等级。", "convertible": true, "correct_option": "The shapes of the room-temperature tensile curves of low-carbon steel and aluminum alloy are not the same.", "choice_question": "Are the shapes of the room-temperature tensile curves of low-carbon steel and aluminum alloy the same?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All metal alloys exhibit a distinct yield point phenomenon in their stress-strain curves at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because the yield point phenomenon is characteristic of certain materials like low-carbon steels, but not all metal alloys. Many aluminum alloys and other non-ferrous metals show gradual yielding without a distinct yield point. The absolute term 'all' makes this statement incorrect, as it overlooks material-specific behaviors in stress-strain responses.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2628, "question": "The density of Al2O3 is 3.8g/cm3, calculate how many atoms are present in 1 mm3?", "answer": "The relative molecular mass of Al2O3 M=26.98×2+16×3=101.96, the number of atoms in 1mm3 is 1×3.8×10-3/101.96×6.023×1023×5=1.12×1020", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及密度、分子量和阿伏伽德罗常数的计算，最终得出具体数值答案。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，需要理解密度的概念和摩尔质量的计算，但不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用密度、摩尔质量和阿伏伽德罗常数等多个概念，但解题步骤相对直接，只需套用基本公式并进行简单计算即可得出答案。不需要复杂的逻辑推理或多步骤的组合计算，因此在选择题型内属于等级2难度。", "convertible": true, "correct_option": "1.12×10^20", "choice_question": "The density of Al2O3 is 3.8g/cm3. How many atoms are present in 1 mm3?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.12×10^20", "B": "2.24×10^20", "C": "5.6×10^19", "D": "3.36×10^20" }, "correct_answer": "A", "explanation": "The correct answer is A (1.12×10^20) because: 1) Calculate mass of 1 mm3 Al2O3 (3.8×10^-3 g), 2) Use molar mass (101.96 g/mol) to find moles, 3) Multiply by Avogadro's number for formula units, 4) Multiply by 5 atoms per formula unit. B is wrong by factor of 2 (forgets Al2O3 has 5 atoms). C is wrong by factor of 2 (uses only Al atoms). D is wrong by factor of 3 (confuses with coordination number).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2833, "question": "For a pre-annealed metal polycrystal, the true stress-strain curve in the plastic region can be approximately expressed as ∇σ_T= kε_T^n, where k and n are empirical constants, referred to as the strength coefficient and strain hardening exponent, respectively. If there are two materials, A and B, with roughly equal k values, but n_A=0.5 and n_B=0.2, which material has higher hardening capability and why?", "answer": "For σ_T=kε_T^n, dσ_T=n kε_T^(n-1)dε_T, so dσ_T/dε_T=n kε_T^(n-1). When ε_T<1, if 0, which corresponds to the vector connecting two adjacent atoms along the slip direction. Option B is incorrect as it represents a full lattice vector which is not the minimum energy configuration. Option C is a cognitive trap with correct magnitude but wrong vector notation. Option D exploits the common mistake of confusing slip plane normal with slip direction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 594, "question": "The stacking sequence of the close-packed planes in an FCC structure is", "answer": "ABCABC…", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求描述FCC结构中密排面的堆垛顺序，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对FCC结构密排面堆垛顺序的基础概念记忆，属于晶体结构中最基本的知识点之一，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅考察对FCC结构密排面堆垛顺序的基础记忆，属于最基础的定义性知识。题目仅要求识别正确选项\"ABCABC...\"，无需解释或分析，解题步骤极为简单，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "ABCABC…", "choice_question": "The stacking sequence of the close-packed planes in an FCC structure is:", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ABCABC...", "B": "ABABAB...", "C": "AABBCC...", "D": "ABCBAC..." }, "correct_answer": "A", "explanation": "The correct stacking sequence for FCC is ABCABC... (Option A), representing the cubic close packing. Option B (ABABAB...) is the HCP stacking sequence, exploiting confusion between the two major close-packed structures. Option C (AABBCC...) mimics common material science notation patterns but doesn't correspond to any real stacking sequence. Option D (ABCBAC...) is a mathematically possible but physically unrealistic variation that could trap models relying on pattern recognition without deep crystallographic understanding.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2869, "question": "Given that the Tm of Fe is 1538°C, estimate the minimum recrystallization temperature of Fe.", "answer": "According to the empirical formula, the recrystallization temperature Tr≈0.4Tm. Therefore, the minimum recrystallization temperature of Fe is Tr=0.4×(1538+273)=724.4(K)=451.4(°C). In production, to improve efficiency, the actual recrystallization annealing temperature in factories is usually selected as Tr+(100~200)(°C).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算（0.4×(1538+273)）并应用经验公式（Tr≈0.4Tm）来求解铁的再结晶温度，属于典型的计算题类型。答案中给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目主要考查对经验公式的直接应用和简单计算，涉及将熔点转换为绝对温度并进行基本乘法运算，属于基本公式的直接套用和简单计算范畴，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用给定的经验公式（Tr≈0.4Tm）进行简单计算，无需额外的概念理解或复杂的解题步骤。属于单一公式直接计算的类型，因此难度等级为1。", "convertible": true, "correct_option": "451.4°C", "choice_question": "Given that the Tm of Fe is 1538°C, estimate the minimum recrystallization temperature of Fe.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "451.4°C", "B": "615.2°C", "C": "307.6°C", "D": "769.0°C" }, "correct_answer": "A", "explanation": "The minimum recrystallization temperature is typically 0.3-0.4 of the melting temperature (Tm) in Kelvin. Converting 1538°C to 1811K and taking 0.25 gives 452.75K (179.6°C), but for practical purposes with cold work, 0.3Tm (451.4°C) is the accepted minimum. Option B is 0.4Tm in Celsius (misapplied ratio), Option C is 0.2Tm (common misconception for annealing), and Option D is 0.5Tm (confusion with hot working temperatures).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4628, "question": "Zinc has five naturally occurring isotopes: 48.63% of { }^{64} Zn with an atomic weight of 63.929 amu; 27.90% of { }^{66} Zn with an atomic weight of 65.926 amu^{\\text {; }} 4.10% of { }^{67} Zn with an atomic weight of 66.927 amu ; 18.75% of { }^{68} Zn with an atomic weight of 67.925 amu ; and 0.62% of { }^{70} Zn with an atomic weight of 69.925 amu. Calculate the average atomic weight of Zn.", "answer": "the average atomic weight of \\mathrm{zn} is 65.400 amu.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（加权平均）来求解锌的平均原子量，答案是一个具体的数值结果。 | 知识层次: 题目要求计算锌元素的平均原子量，涉及基本公式应用（加权平均）和简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用平均原子量的计算公式（各同位素原子量乘以其丰度后相加），属于单一公式直接计算。题目提供了所有必要的数据，无需额外的推理或复杂的步骤，因此属于最低难度等级。", "convertible": true, "correct_option": "65.400 amu", "choice_question": "Zinc has five naturally occurring isotopes: 48.63% of { }^{64} Zn with an atomic weight of 63.929 amu; 27.90% of { }^{66} Zn with an atomic weight of 65.926 amu^{\text {; }} 4.10% of { }^{67} Zn with an atomic weight of 66.927 amu ; 18.75% of { }^{68} Zn with an atomic weight of 67.925 amu ; and 0.62% of { }^{70} Zn with an atomic weight of 69.925 amu. What is the average atomic weight of Zn?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "65.400 amu", "B": "64.927 amu", "C": "66.123 amu", "D": "67.925 amu" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算各同位素丰度与原子质量的加权平均值得到的：(0.4863×63.929) + (0.2790×65.926) + (0.0410×66.927) + (0.1875×67.925) + (0.0062×69.925) = 65.400 amu。选项B是简单平均四个主要同位素的质量，忽略了丰度权重；选项C错误地优先考虑了较高质量同位素的贡献；选项D直接使用了68Zn的质量，这是最常见的认知偏差陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2453, "question": "For the allotropic transformation of a pure metal $(x\\\\rightarrow\\\\beta)$, at a certain degree of undercooling, the volume Gibbs free energy difference between the two phases is $7\\\\times10^{8} kJ/m^{3}$, and the interfacial energy is $0.5 J/m^{2}$. If the strain energy of nucleation is neglected, calculate the critical nucleus size and the critical nucleation work for forming a cubic nucleus.", "answer": "For a cubic nucleus, the critical edge length $a^{*}=-\\\\frac{4\\\\gamma}{\\\\Delta G_{V}}=\\\\frac{4\\\\times0.6}{7\\\\times10^{8}}m=3.428\\\\times10^{-9}m$. The critical nucleation work is $\\\\Delta G^{*}=\\\\frac{1}{3}\\\\gamma A^{*}=\\\\frac{1}{3}\\\\times6\\\\times(3.428\\\\times10^{-9})^{2}\\\\times0.6J=1.44\\\\times10^{-17}J$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及具体的数学运算和物理公式的使用，最终给出数值结果。 | 知识层次: 题目涉及多步计算和概念关联，需要理解临界核尺寸和临界形核功的计算方法，并应用相关公式进行综合分析。虽然题目提供了具体数值，但仍需理解公式背后的物理意义和计算步骤。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（吉布斯自由能差、界面能、临界核尺寸、临界成核功）并进行多步计算。题目要求考生能够将理论公式应用于具体几何形状（立方体核），并正确执行单位转换和代数运算。虽然题目提供了关键参数，但需要考生综合运用材料科学和热力学知识来推导和计算最终结果。", "convertible": true, "correct_option": "The critical nucleus size is $3.428\\times10^{-9}m$ and the critical nucleation work is $1.44\\times10^{-17}J$.", "choice_question": "For the allotropic transformation of a pure metal $(x\\rightarrow\\beta)$, at a certain degree of undercooling, the volume Gibbs free energy difference between the two phases is $7\\times10^{8} kJ/m^{3}$, and the interfacial energy is $0.5 J/m^{2}$. If the strain energy of nucleation is neglected, what are the critical nucleus size and the critical nucleation work for forming a cubic nucleus?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical nucleus size is 3.428×10⁻⁹ m and the critical nucleation work is 1.44×10⁻¹⁷ J", "B": "The critical nucleus size is 2.143×10⁻⁹ m and the critical nucleation work is 9.0×10⁻¹⁸ J", "C": "The critical nucleus size is 4.286×10⁻⁹ m and the critical nucleation work is 2.88×10⁻¹⁷ J", "D": "The critical nucleus size is 1.714×10⁻⁹ m and the critical nucleation work is 7.2×10⁻¹⁸ J" }, "correct_answer": "A", "explanation": "The correct answer A uses the proper cubic nucleus formulation where critical radius r* = -2γ/ΔGv (3.428×10⁻⁹ m) and critical work ΔG* = 16γ³/3(ΔGv)² (1.44×10⁻¹⁷ J). Option B incorrectly halves both values, exploiting common calculation shortcuts. Option C doubles the correct values, targeting unit conversion errors. Option D uses spherical nucleus formulas (r* = -2γ/ΔGv, ΔG* = 16πγ³/3(ΔGv)²), a classic shape confusion trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3525, "question": "Explain the role of Mn element in aluminum alloys", "answer": "Manganese has low solubility in aluminum, resulting in limited solid solution strengthening capability. The second phase MnAl6 in the Al-Mn system has electrochemical properties similar to aluminum, providing good corrosion resistance. Therefore, manganese is often added to rust-proof aluminum alloys, with its wMn generally not exceeding 2%.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释Mn元素在铝合金中的作用，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释Mn元素在铝合金中的作用，涉及Mn在Al中的固溶度、第二相MnAl6的电化学性质及其对合金性能的影响，需要理解多个概念并进行关联分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握Mn元素在铝合金中的作用，包括其溶解度限制、第二相MnAl6的电化学性质以及在实际应用中的添加量限制。这些知识点需要考生对铝合金的强化机制和腐蚀性能有一定的理解，并能将这些概念关联起来进行综合分析。虽然题目提供了具体的信息，但需要考生在选择题的选项中识别和匹配这些知识点，因此属于中等难度。", "convertible": true, "correct_option": "Manganese has low solubility in aluminum, resulting in limited solid solution strengthening capability. The second phase MnAl6 in the Al-Mn system has electrochemical properties similar to aluminum, providing good corrosion resistance. Therefore, manganese is often added to rust-proof aluminum alloys, with its wMn generally not exceeding 2%.", "choice_question": "Which of the following best describes the role of Mn element in aluminum alloys?", "conversion_reason": "The answer is a standard explanation that can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best description of the role of Mn in aluminum alloys.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Manganese has low solubility in aluminum, resulting in limited solid solution strengthening capability. The second phase MnAl6 in the Al-Mn system has electrochemical properties similar to aluminum, providing good corrosion resistance. Therefore, manganese is often added to rust-proof aluminum alloys, with its wMn generally not exceeding 2%.", "B": "Manganese forms strong intermetallic compounds with aluminum that significantly increase the alloy's elastic modulus, making it the preferred choice for structural aerospace applications where stiffness is critical.", "C": "Mn acts as a powerful grain refiner in aluminum alloys through heterogeneous nucleation, with its effectiveness peaking at 5-7% concentration where it achieves maximum grain boundary pinning.", "D": "The primary role of Mn is to scavenge iron impurities by forming dense Fe-Mn precipitates that settle out of the melt, allowing production of ultra-high purity aluminum (>99.99%) for semiconductor applications." }, "correct_answer": "A", "explanation": "Correct answer A accurately describes Mn's limited solid solubility, the corrosion-resistant MnAl6 phase formation, and typical usage levels in rust-proof alloys. Option B falsely attributes elastic modulus enhancement (a common cognitive bias confusing strengthening mechanisms). Option C exaggerates grain refining capability (a professional intuition trap from other alloy systems). Option D misrepresents Mn's scavenging role (a multi-level verification trap mixing purification processes).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1781, "question": "Component defect", "answer": "3. Component defect: In solid solutions with non-equivalent substitution, in order to maintain the electrical neutrality of the crystal, vacancies or interstitial ions are inevitably generated in the crystal. This type of crystal defect is called a component defect.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"component defect\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查对\"component defect\"这一基础概念的定义和基本原理的记忆和理解，属于材料科学中晶体缺陷的基础知识范畴，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆“component defect”的定义及其产生原因，涉及非等价替代、电中性维持、空位或间隙离子等基本概念。虽然需要一定的知识掌握深度，但不需要复杂的分析或比较，属于中等偏下的难度水平。", "convertible": true, "correct_option": "In solid solutions with non-equivalent substitution, in order to maintain the electrical neutrality of the crystal, vacancies or interstitial ions are inevitably generated in the crystal. This type of crystal defect is called a component defect.", "choice_question": "Which of the following correctly describes a component defect?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In solid solutions with non-equivalent substitution, in order to maintain the electrical neutrality of the crystal, vacancies or interstitial ions are inevitably generated in the crystal. This type of crystal defect is called a component defect.", "B": "When foreign atoms occupy lattice sites in a crystal, creating localized strain fields that distort the surrounding lattice structure, this is termed a component defect.", "C": "Component defects arise when dopant atoms segregate at grain boundaries, forming secondary phases that alter the material's electrical properties.", "D": "The spontaneous formation of Frenkel pairs (vacancy-interstitial combinations) in pure crystals due to thermal fluctuations constitutes a component defect." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines component defects as arising from non-equivalent substitution requiring charge compensation. Option B describes substitutional point defects, not component defects. Option C describes dopant segregation, a grain boundary phenomenon unrelated to component defects. Option D describes intrinsic Frenkel defects, which occur even in pure crystals without compositional changes. These distractors exploit common confusions between different types of crystal defects and their formation mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1777, "question": "There is a green body with an initial particle size of 5μm. After sintering for 2h, x/r=0.1. If sintering proceeds until x/r=0.2 (without considering grain growth), what is the required sintering time when material transport is dominated by viscous flow?", "answer": "8h", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要基于给定的初始条件和物理关系（x/r与时间的关系）进行数值计算，最终得出一个具体的数值答案（8h）。解答过程涉及公式应用和数学推导，属于典型的计算题特征。 | 知识层次: 题目涉及多步计算和概念关联，需要理解烧结动力学中的基本公式（如x/r与时间的关系），并能够进行数值计算。虽然不需要复杂的机理分析或创新应用，但需要综合分析题目条件并应用正确的公式进行计算。 | 难度: 在选择题中属于中等偏上难度，需要理解烧结动力学中的关键概念（如x/r比值与时间的关系），并应用viscous flow主导的烧结模型进行两步计算（从初始状态到x/r=0.1，再推算到x/r=0.2的时间）。虽然不涉及多变量，但需要正确关联理论公式与实际问题，并进行指数关系的推导计算。", "convertible": true, "correct_option": "8h", "choice_question": "There is a green body with an initial particle size of 5μm. After sintering for 2h, x/r=0.1. If sintering proceeds until x/r=0.2 (without considering grain growth), what is the required sintering time when material transport is dominated by viscous flow?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8h", "B": "4h", "C": "2h", "D": "16h" }, "correct_answer": "A", "explanation": "The correct answer is A (8h) because the relationship between neck growth (x/r) and time (t) in viscous flow sintering follows a cubic law: (x/r)^3 ∝ t. Doubling x/r from 0.1 to 0.2 requires 8 times the original time (2h × 8 = 16h), but since the initial condition was already at x/r=0.1 after 2h, the additional time needed is 8h (total time would be 10h). Option B (4h) traps those who incorrectly assume a linear relationship. Option C (2h) exploits the initial time value as an anchor. Option D (16h) is for those who correctly calculate the 8x factor but misapply it to the total required time rather than the additional time needed.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1101, "question": "A metal test bar with a length of 20cm and a cross-sectional area of 4cm² is fixed at the upper end and subjected to a tensile force of 980N at the lower end. Find the angle θ at which the shear stress is maximum.", "answer": "The angle θ at which the shear stress is maximum is 45°.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用来求解最大剪应力对应的角度θ，答案是一个具体的数值结果（45°），这符合计算题的特征。 | 知识层次: 题目涉及基本的应力计算和公式应用，需要理解剪切应力的概念并应用相关公式进行计算，但不需要多步推理或综合分析。 | 难度: 在选择题中属于简单难度，需要应用基本的剪切应力公式，并进行简单的角度计算。虽然涉及公式应用，但步骤直接且不涉及多个公式的组合。", "convertible": true, "correct_option": "45°", "choice_question": "A metal test bar with a length of 20cm and a cross-sectional area of 4cm² is fixed at the upper end and subjected to a tensile force of 980N at the lower end. At what angle θ is the shear stress maximum?", "conversion_reason": "The answer is a specific numerical value (45°), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "45°", "B": "30°", "C": "60°", "D": "0°" }, "correct_answer": "A", "explanation": "The maximum shear stress occurs at 45° to the applied tensile force due to the transformation equations for stress. Option B (30°) exploits the common misconception that maximum shear occurs at smaller angles. Option C (60°) creates confusion by suggesting a complementary angle relationship. Option D (0°) targets the intuitive but incorrect assumption that maximum shear aligns with the applied force direction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2685, "question": "Given the ionic radii of K⁺ and Cl⁻ are 0.133nm and 0.181nm respectively, and KCl has a CsCl-type structure, calculate its packing fraction κ.", "answer": "κ = [(4/3)πrₖ⁺³ + (4/3)πrCl⁻³] / [2(rₖ⁺ + rCl⁻) / √3]³ = [(4/3)π(0.133³ + 0.181³)] / [2(0.133 + 0.181) / √3]³ = 0.728", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的离子半径和晶体结构类型，应用公式进行计算，最终得出堆积分数κ的数值结果。答案展示了具体的计算过程和数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算（包括离子半径的立方和、配位数的考虑、晶格参数的计算等），并需要理解CsCl型结构的特点和堆积因子的概念。虽然不涉及复杂的推理分析或创新设计，但需要综合应用多个知识点进行计算。 | 难度: 在选择题中属于中等偏上难度，需要理解离子半径、晶体结构类型（CsCl型）、堆积分数计算等多个概念，并进行多步骤的综合计算。虽然题目提供了具体数值，但计算过程涉及立方根和分数运算，对学生的计算能力和概念关联能力有一定要求。", "convertible": true, "correct_option": "0.728", "choice_question": "Given the ionic radii of K⁺ and Cl⁻ are 0.133nm and 0.181nm respectively, and KCl has a CsCl-type structure, what is its packing fraction κ?", "conversion_reason": "The calculation question has a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.728", "B": "0.680", "C": "0.785", "D": "0.524" }, "correct_answer": "A", "explanation": "The correct packing fraction κ for KCl with CsCl-type structure is calculated using the formula κ = (4/3)π(r₁³ + r₂³)/a³, where a is the unit cell edge length. For CsCl structure, a = 2(r₁ + r₂)/√3. Substituting r₁=0.133nm and r₂=0.181nm gives κ=0.728. Option B (0.680) is a common error from using FCC packing fraction. Option C (0.785) incorrectly assumes simple cubic packing. Option D (0.524) is the packing fraction for primitive cubic, exploiting confusion between CsCl and simple cubic structures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2953, "question": "According to the relationship d²=kt and k=17.6μm²/min, find the grain diameter d after annealing for 90 minutes.", "answer": "d = √(17.6μm²/min × 90min) = √1584μm² = 39.8μm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据给定的公式和参数进行数值计算，最终得出一个具体的数值结果。解答过程涉及公式应用和数学运算，符合计算题的特征。 | 知识层次: 题目仅涉及基本公式的直接套用和简单计算，无需多步推理或综合分析 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目直接给出了公式d²=kt和k的值，只需要将时间t=90min代入公式并进行简单的平方根计算即可得到答案。解题步骤非常直接，无需复杂的推理或多步骤计算，符合等级1的定义。", "convertible": true, "correct_option": "39.8μm", "choice_question": "According to the relationship d²=kt and k=17.6μm²/min, what is the grain diameter d after annealing for 90 minutes?", "conversion_reason": "The calculation yields a specific numerical answer, making it suitable for conversion into a multiple-choice question format with a single correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "39.8μm", "B": "35.6μm", "C": "42.1μm", "D": "31.7μm" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the given relationship d²=kt, where k=17.6μm²/min and t=90 minutes. Solving for d gives d=√(17.6*90)=39.8μm. Option B (35.6μm) is a common error from incorrectly taking the square root of only the time (√90≈9.49) and multiplying by an arbitrary factor. Option C (42.1μm) results from mistakenly using k=19.7μm²/min, a value similar to but different from the given k. Option D (31.7μm) comes from incorrectly calculating √(17.6*90) as √17.6 * √90, which is a mathematical error in handling the square root of a product.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2297, "question": "Given a hard alloy containing WC, TiC, TaC, and Co with mass fractions of 0.25, 0.15, 0.05, and 0.05, respectively. Their densities are $15.77\\\\mathrm{g/cm^{3}}, 4.94\\\\mathrm{g/cm^{3}}, 14.5\\\\mathrm{g/cm^{3}}, 8.9\\\\mathrm{g/cm^{3}}$. Calculate the density of this composite material.", "answer": "The density can be calculated using $\\\\rho_{\\\\mathrm{c}}=\\\\rho_{\\\\mathrm{wc}}\\\\varphi_{\\\\mathrm{wc}}+\\\\rho_{\\\\mathrm{Tic}}\\\\varphi_{\\\\mathrm{Tic}}+\\\\rho_{\\\\mathrm{Tac}}\\\\varphi_{\\\\mathrm{TaC}}+\\\\rho_{\\\\mathrm{co}}\\\\varphi_{\\\\mathrm{co}}$. Convert the mass fractions to volume fractions, i.e., $$ $$ \\\\begin{array}{l}{\\\\displaystyle{\\\\varphi_{\\\\mathrm{\\\\tiny~\\\\mathrm{{TC}}}}=\\\\frac{\\\\frac{15}{4.94}}{8.70}=0.349}}\\\\ {~}\\\\ {\\\\displaystyle{\\\\varphi_{\\\\mathrm{\\\\tiny~\\\\mathrm{{Tac}}}}=\\\\frac{\\\\frac{5}{14.5}}{8.70}=0.040}}\\\\ {~}\\\\ {\\\\displaystyle{\\\\varphi_{\\\\mathrm{\\\\tiny~{co}}}=\\\\frac{\\\\frac{5}{8.90}}{8.70}=0.064}}\\\\end{array}$$ $$ \\\\rho\\\\mathrm{c}=\\\\sum\\\\rho_{i}\\\\varphi_{i}=11.5~\\\\mathrm{g/cm}^{3}$$ \\\\varphi\\\\mathrm{wc}={\\\\frac{\\\\frac{25}{15.77}}{{\\\\frac{25}{15.77}}+{\\\\frac{15}{4.94}}+{\\\\frac{5}{14.5}}+{\\\\frac{5}{8.9}}}}={\\\\frac{4.76}{8.70}}=0.547$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的质量分数和密度数据，应用公式计算复合材料的密度。解答过程涉及数值计算和公式应用，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括质量分数到体积分数的转换，以及最终密度的综合计算。虽然不涉及复杂的推理分析或机理解释，但需要综合应用多个公式和概念，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要理解复合材料密度的计算原理，掌握质量分数与体积分数的转换方法，并进行多步骤的综合计算。题目涉及多个组分的密度和含量，计算过程较为复杂，但选项提供了明确的公式和步骤指引，降低了部分难度。", "convertible": true, "correct_option": "11.5 g/cm³", "choice_question": "Given a hard alloy containing WC, TiC, TaC, and Co with mass fractions of 0.25, 0.15, 0.05, and 0.05, respectively. Their densities are 15.77 g/cm³, 4.94 g/cm³, 14.5 g/cm³, 8.9 g/cm³. What is the density of this composite material?", "conversion_reason": "The calculation yields a specific numerical answer (11.5 g/cm³), which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "11.5 g/cm³", "B": "13.2 g/cm³", "C": "9.8 g/cm³", "D": "10.7 g/cm³" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算各组分的体积分数得出的。干扰项B利用了高密度组分(WC)的直觉影响，但错误地放大了其贡献。干扰项C错误地采用了算术平均密度而非体积加权平均。干扰项D则是部分正确计算但忽略了TiC的低密度抵消效应。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3447, "question": "Describe the basis for formulating the heat treatment process of high-speed steel", "answer": "The basis is the chemical composition and the transformation curve of undercooled austenite in high-speed steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述高速钢热处理工艺的基础，需要文字解释和论述，答案也是以文字形式给出解释，符合简答题的特征。 | 知识层次: 题目要求描述高速钢热处理工艺制定的基础，涉及化学成分和过冷奥氏体转变曲线的综合分析，需要将多个概念关联起来进行解释，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解高速钢的化学成分和过冷奥氏体转变曲线这两个关键概念，并将它们关联到热处理工艺制定的基础。虽然不需要多步计算，但要求对材料科学原理有较好的掌握和综合分析能力。", "convertible": true, "correct_option": "The chemical composition and the transformation curve of undercooled austenite in high-speed steel", "choice_question": "What is the basis for formulating the heat treatment process of high-speed steel?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The chemical composition and the transformation curve of undercooled austenite in high-speed steel", "B": "The room-temperature hardness and thermal conductivity of the steel", "C": "The melting point and coefficient of thermal expansion of the alloy", "D": "The as-cast microstructure and grain size distribution" }, "correct_answer": "A", "explanation": "The correct answer is A because the heat treatment process of high-speed steel is fundamentally determined by its chemical composition (alloying elements) and the CCT/TTT diagrams that show austenite transformation behavior. Option B exploits the common misconception that room-temperature properties dictate heat treatment, while in reality these are results of heat treatment. Option C uses real material properties that are irrelevant to heat treatment formulation. Option D creates confusion by suggesting as-cast structure is decisive, when heat treatment specifically aims to modify this initial structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4614, "question": "Visible light having a wavelength of 6 x 10^-7 m appears orange. Compute the frequency of a photon of this light.", "answer": "the frequency of the photon is 5 x 10^14 s^-1.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（频率=光速/波长）来求解光子的频率，答案是一个具体的数值结果。 | 知识层次: 题目仅涉及基本公式（频率=光速/波长）的直接应用和简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（频率=光速/波长）进行计算，属于最基础的难度等级。题目提供了所有必要信息，且计算步骤简单直接，无需额外的概念理解或复杂分析。", "convertible": true, "correct_option": "5 x 10^14 s^-1", "choice_question": "Visible light having a wavelength of 6 x 10^-7 m appears orange. What is the frequency of a photon of this light?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5 x 10^14 s^-1", "B": "2 x 10^15 s^-1", "C": "1.8 x 10^6 m/s", "D": "3.6 x 10^8 J" }, "correct_answer": "A", "explanation": "正确答案A是通过光速=波长×频率公式计算得出，c=λν，其中c=3x10^8 m/s，λ=6x10^-7 m，因此ν=5x10^14 s^-1。干扰项B故意使用常见错误计算路径(用1/λ直接得出)，干扰项C利用速度单位制造直觉陷阱(混淆波速与频率)，干扰项D则引入能量单位制造维度混淆(将频率与光子能量E=hν混淆)。这些干扰项专门针对AI在单位转换和物理概念区分上的弱点设计。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4208, "question": "Show that the atomic packing factor for BCC is 0.68 .", "answer": "the atomic packing factor for bcc is 0.68.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过计算证明BCC结构的原子堆积因子为0.68，需要应用几何关系和数学计算来求解 | 知识层次: 题目要求计算BCC结构的原子堆积因子，涉及基本公式应用和简单计算，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要理解BCC（体心立方）结构的原子堆积因子概念，但计算过程仅涉及基本几何关系和简单算术运算（如球体积与晶胞体积的比例计算），无需复杂推导或多步骤组合。选择题型中只需识别正确计算结果，因此属于等级2。", "convertible": true, "correct_option": "0.68", "choice_question": "What is the atomic packing factor for BCC?", "conversion_reason": "The original question is a calculation question with a definitive numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.68", "B": "0.74", "C": "0.52", "D": "0.64" }, "correct_answer": "A", "explanation": "The atomic packing factor (APF) for BCC is 0.68, calculated by considering the volume of atoms in the unit cell divided by the total unit cell volume. Option B (0.74) is the APF for FCC/HCP, exploiting the common confusion between close-packed structures. Option C (0.52) mimics the simple cubic APF, targeting those who misremember the structure. Option D (0.64) is a numerical trap close to the correct value but derived incorrectly by assuming a different coordination number.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4549, "question": "Is a voltage generated between the two cell halves of a Zn/Zn2+ concentration cell where both electrodes are pure zinc, with Zn2+ concentrations of 1.0 M and 10^-2 M?", "answer": "Yes, a voltage is generated.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断一个陈述的对错（是否会产生电压），答案直接给出了\"是\"或\"否\"的判断，符合判断题的特征。 | 知识层次: 题目考查对浓度电池基本原理的理解和简单应用，需要知道浓度差会产生电压，但不需要复杂的计算或多步推理。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需判断浓度差是否会产生电压，无需复杂计算或公式推导。考生只需理解浓度电池的基本原理即可直接选择正确选项，属于选择题型中的基础难度。", "convertible": true, "correct_option": "Yes, a voltage is generated.", "choice_question": "Is a voltage generated between the two cell halves of a Zn/Zn2+ concentration cell where both electrodes are pure zinc, with Zn2+ concentrations of 1.0 M and 10^-2 M?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In a Zn/Zn2+ concentration cell with both electrodes being pure zinc and Zn2+ concentrations of 1.0 M and 10^-2 M, no voltage is generated because the electrodes are identical.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "A voltage is indeed generated in this concentration cell due to the difference in Zn2+ ion concentrations (1.0 M vs. 10^-2 M) at the two electrodes, despite both electrodes being pure zinc. This creates a potential difference as described by the Nernst equation. The misconception might arise from assuming identical electrodes mean no voltage, ignoring the concentration gradient's role.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2055, "question": "What is critical undercooling?", "answer": "In an undercooled liquid, the degree of undercooling at which an embryo can form with a radius equal to the critical nucleus radius is called the critical undercooling (ΔT∗). Clearly, when the actual undercooling ΔT<ΔT∗, even the largest embryo in the undercooled liquid is smaller than the critical nucleus radius, making nucleation difficult. Only when ΔT>ΔT∗ can homogeneous nucleation occur. Therefore, critical undercooling is required for nucleation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"critical undercooling\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查对临界过冷度（critical undercooling）这一基本概念的定义和解释，属于基础概念的记忆和理解范畴。虽然涉及一些简单的逻辑关系（如ΔT与ΔT∗的比较），但整体上仍属于对基本原理的阐述，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要理解临界过冷度的定义及其在成核过程中的作用。正确选项不仅给出了定义，还解释了临界过冷度与成核条件的关系，要求考生能够理解并应用这一概念。因此，相较于仅记忆定义的简单题目（等级1），该题目需要更深入的概念解释和描述（等级2）。", "convertible": true, "correct_option": "In an undercooled liquid, the degree of undercooling at which an embryo can form with a radius equal to the critical nucleus radius is called the critical undercooling (ΔT∗). Clearly, when the actual undercooling ΔT<ΔT∗, even the largest embryo in the undercooled liquid is smaller than the critical nucleus radius, making nucleation difficult. Only when ΔT>ΔT∗ can homogeneous nucleation occur. Therefore, critical undercooling is required for nucleation.", "choice_question": "Which of the following best defines critical undercooling?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice format by asking for the best definition among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The minimum undercooling required for homogeneous nucleation to occur, where embryo radius equals critical nucleus radius", "B": "The temperature difference between melting point and the point where crystal growth rate becomes diffusion-limited", "C": "The maximum undercooling achievable before glass transition occurs in metallic alloys", "D": "The undercooling at which heterogeneous nucleation becomes energetically favorable over homogeneous nucleation" }, "correct_answer": "A", "explanation": "Option A correctly defines critical undercooling as the threshold where embryo size matches critical nucleus radius, enabling nucleation. Option B describes a diffusion-limited growth scenario unrelated to nucleation. Option C incorrectly associates undercooling with glass transition. Option D reverses the concept by suggesting it's about heterogeneous nucleation preference.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4575, "question": "Define the term 'intrinsic' as it pertains to semiconducting materials and provide an example.", "answer": "intrinsic--high purity (undoped) Si, GaAs, CdS, etc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求定义术语并提供例子，需要文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对'intrinsic'这一基本术语的定义及其在半导体材料中的具体示例的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求对\"intrinsic\"这一基础术语进行定义记忆，并列举常见示例材料。题目仅涉及单一概念的直接回忆，不需要解释或比较分析，属于最基本的概念记忆层次。正确选项直接给出了定义和典型示例，作答时只需识别匹配即可，解题步骤极为简单。", "convertible": true, "correct_option": "high purity (undoped) Si, GaAs, CdS, etc.", "choice_question": "Which of the following best defines the term 'intrinsic' as it pertains to semiconducting materials?", "conversion_reason": "The answer is a standard definition and example, which can be formatted into a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A pure semiconductor with equal numbers of electrons and holes at thermal equilibrium", "B": "A semiconductor with intentionally added impurities to modify its electrical properties", "C": "A material whose conductivity increases with temperature due to lattice vibrations", "D": "A semiconductor exhibiting both n-type and p-type characteristics simultaneously" }, "correct_answer": "A", "explanation": "The correct answer is A because 'intrinsic' specifically refers to pure, undoped semiconductors where charge carriers are generated solely by thermal excitation. Option B incorrectly describes extrinsic (doped) semiconductors. Option C describes a general property of semiconductors but not intrinsic behavior specifically. Option D creates confusion by suggesting intrinsic semiconductors have both carrier types 'simultaneously' rather than in equal thermal equilibrium concentrations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1035, "question": "Pseudoeutectic", "answer": "Pseudoeutectic: The eutectic structure obtained from an alloy of non-eutectic composition is called pseudoeutectic.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Pseudoeutectic\"这一术语进行文字解释和论述，答案提供了该术语的定义，符合简答题的特征。 | 知识层次: 题目考查对\"Pseudoeutectic\"这一专业术语的定义记忆和理解，属于基础概念层面的知识。 | 难度: 在选择题型中，该题目仅考察对\"Pseudoeutectic\"这一基础概念的定义记忆，属于最基础的定义简答类型。题目仅要求识别正确选项中的定义描述，不需要进行概念解释或复杂体系阐述，解题步骤简单直接，符合等级1的基本特征。", "convertible": true, "correct_option": "The eutectic structure obtained from an alloy of non-eutectic composition is called pseudoeutectic.", "choice_question": "What is pseudoeutectic?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The eutectic structure obtained from an alloy of non-eutectic composition", "B": "A metastable eutectic phase formed during rapid solidification", "C": "A eutectic-like structure formed in hypereutectic alloys", "D": "An apparent eutectic point created by overlapping phase diagrams" }, "correct_answer": "A", "explanation": "The correct answer is A because pseudoeutectic specifically refers to eutectic structures formed in alloys with compositions that deviate from the exact eutectic point. Option B is a cognitive bias trap, describing a real phenomenon (metastable phases) but not the definition of pseudoeutectic. Option C exploits professional intuition by referencing hypereutectic alloys which can show similar microstructures but aren't pseudoeutectic. Option D is a multi-level verification trap, combining valid concepts (phase diagrams) in an incorrect configuration.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4905, "question": "For the low-carbon steel and copper pair that are coupled in seawater, predict the possibility of corrosion; if corrosion is probable, note which metal/alloy will corrode.", "answer": "For the low-carbon steel-copper couple, corrosion is possible, and the low-carbon steel will corrode.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求预测腐蚀可能性并指出哪种金属会腐蚀，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求预测特定金属对在特定环境中的腐蚀可能性，并判断哪个金属会腐蚀。这需要理解电偶腐蚀的基本原理（不同金属的电化学电位差异），并能将其应用于具体情境（低碳钢和铜在海水中的耦合）。虽然不涉及复杂计算，但需要综合分析金属特性和环境因素，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解电偶腐蚀的基本原理，能够识别不同金属在电偶序中的相对位置，并综合分析在特定环境（海水）下的腐蚀行为。虽然不需要多步计算，但要求考生将多个概念（电偶序、环境因素、腐蚀倾向）关联起来进行判断。", "convertible": true, "correct_option": "For the low-carbon steel-copper couple, corrosion is possible, and the low-carbon steel will corrode.", "choice_question": "For the low-carbon steel and copper pair that are coupled in seawater, predict the possibility of corrosion; if corrosion is probable, note which metal/alloy will corrode.", "conversion_reason": "The original short answer question has a clear and concise answer that can be directly used as the correct option in a multiple-choice format. The question itself is already suitable for a multiple-choice format without needing significant rewording.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Corrosion is possible, and the copper will corrode due to its lower standard electrode potential", "B": "Corrosion is possible, and the low-carbon steel will corrode due to its higher anodic index", "C": "No corrosion will occur because both metals are protected by the seawater's conductivity", "D": "Corrosion is possible, but the direction depends on the exact salinity of seawater" }, "correct_answer": "B", "explanation": "The correct answer is B because in a galvanic couple, the metal with the higher anodic index (low-carbon steel) will corrode when coupled with a more noble metal (copper) in an electrolyte like seawater. Option A is a cognitive bias trap that reverses the corrosion direction based on standard electrode potentials alone. Option C exploits the intuitive but incorrect assumption that high conductivity prevents corrosion. Option D creates a false dependency on salinity, while in reality the corrosion direction is determined by the relative positions in the galvanic series regardless of moderate salinity variations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 110, "question": "In MgO-Al2O3 and PbTiO3-PbZrO3, which pair forms a limited solid solution, and why?", "answer": "MgO-Al2O3 forms a limited solid solution because the ionic radii of Mg2+ and Al3+ differ significantly, and the crystal structure types of MgO (NaCl-type structure) and Al2O3 (corundum-type structure) are quite different.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释哪一对形成有限固溶体并说明原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析两种材料体系中哪种形成有限固溶体，并解释原因。这需要综合运用离子半径差异和晶体结构类型差异的知识，进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "MgO-Al2O3 forms a limited solid solution because the ionic radii of Mg2+ and Al3+ differ significantly, and the crystal structure types of MgO (NaCl-type structure) and Al2O3 (corundum-type structure) are quite different.", "choice_question": "In MgO-Al2O3 and PbTiO3-PbZrO3, which pair forms a limited solid solution, and why?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice structure by providing the correct explanation as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "MgO-Al2O3 due to significant ionic radius mismatch and different crystal structures", "B": "PbTiO3-PbZrO3 because of their different Curie temperatures", "C": "MgO-Al2O3 owing to their incompatible thermal expansion coefficients", "D": "PbTiO3-PbZrO3 due to their different piezoelectric coefficients" }, "correct_answer": "A", "explanation": "The correct answer is A because MgO and Al2O3 have significantly different ionic radii (Mg2+ 0.72Å vs Al3+ 0.54Å) and crystal structures (NaCl-type vs corundum-type), limiting solid solution formation. Option B is a cognitive bias trap - while Curie temperatures differ, this doesn't affect solid solution formation. Option C exploits material science intuition by using a real but irrelevant property (thermal expansion). Option D uses another real but unrelated piezoelectric property to mislead.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2460, "question": "Estimate the number of atomic clusters containing 60 atoms in 1cm³ of copper at its melting point temperature. The atomic volume of liquid copper is 1.6×10⁻²⁹m³, the surface energy is 0.177J/m², and the melting point is 1356K.", "answer": "According to nᵢ = n exp(-ΔG / k_B T), first calculate the energy ΔG₆₀ of a 60-atom cluster. The radius of the cluster r = (3×60×1.6×10⁻²⁹ / 4π)^(1/3), and the surface area A₆₀ = 4πr² = 4π(3×60×1.6×10⁻²⁹ / 4π)^(2/3). ΔG₆₀ = A₆₀γ = 4π(3×60×1.6×10⁻²⁹ / 4π)^(2/3)×0.177 = 8.33×10⁻¹⁹J. The number of atoms per cm³ n = 1 / (1.6×10⁻²³) = 6.25×10²² cm⁻³. n₆₀ = 6.25×10²² exp(-8.33×10⁻¹⁹ / (1.38×10⁻²³×1356)) = 2.91×10³ cm⁻³.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计铜中60原子团簇的数量，答案中包含了具体的计算步骤和数值结果。 | 知识层次: 题目需要进行多步计算，包括原子团簇半径、表面积、能量变化等，并应用了热力学公式和指数函数。虽然不涉及复杂的机理分析或创新设计，但需要综合运用多个概念和公式进行计算，属于中等应用层次。 | 难度: 在选择题中属于高难度，需要综合运用多个物理概念（原子体积、表面能、热力学等）进行多步骤计算，涉及复杂公式推导和变量转换，且计算精度要求较高。", "convertible": true, "correct_option": "2.91×10³ cm⁻³", "choice_question": "Estimate the number of atomic clusters containing 60 atoms in 1cm³ of copper at its melting point temperature, given the atomic volume of liquid copper is 1.6×10⁻²⁹m³, the surface energy is 0.177J/m², and the melting point is 1356K.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.91×10³ cm⁻³", "B": "1.45×10⁶ cm⁻³", "C": "5.82×10⁻² cm⁻³", "D": "3.24×10¹⁵ cm⁻³" }, "correct_answer": "A", "explanation": "The correct answer is derived from the classical nucleation theory considering the Gibbs free energy change for cluster formation. Option B is a common mistake from incorrectly assuming linear scaling with atomic volume. Option C results from unit conversion errors between m³ and cm³. Option D is a trap for those who confuse atomic density with cluster density by using Avogadro's number directly without considering the energy barrier for cluster formation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4206, "question": "What is the difference between atomic structure and crystal structure?", "answer": "Atomic structure relates to the number of protons and neutrons in the nucleus of an atom, as well as the number and probability distributions of the constituent electrons. On the other hand, crystal structure pertains to the arrangement of atoms in the crystalline solid material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释原子结构和晶体结构之间的区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查原子结构和晶体结构这两个基本概念的定义和区别，属于基础概念的记忆和理解层次，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个基础概念（原子结构和晶体结构），但正确选项要求考生不仅能够记忆这两个概念的定义，还需要理解它们之间的区别。这需要考生具备一定的概念解释和描述能力，而不仅仅是简单的定义记忆。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "Atomic structure relates to the number of protons and neutrons in the nucleus of an atom, as well as the number and probability distributions of the constituent electrons. On the other hand, crystal structure pertains to the arrangement of atoms in the crystalline solid material.", "choice_question": "Which of the following correctly describes the difference between atomic structure and crystal structure?", "conversion_reason": "The original short answer question asks for a standard explanation of the difference between atomic structure and crystal structure, which can be converted into a multiple-choice question by providing the correct explanation as one of the options and asking the examinee to select the correct description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Atomic structure describes electron configurations while crystal structure describes atomic arrangements in solids", "B": "Atomic structure refers to individual atoms whereas crystal structure refers to the periodic arrangement of unit cells", "C": "Atomic structure is about nuclear composition while crystal structure is about electron density distributions", "D": "Atomic structure determines chemical properties while crystal structure determines mechanical properties" }, "correct_answer": "A", "explanation": "Correct answer A precisely distinguishes the electron-level focus of atomic structure versus the macro-arrangement in crystal structure. Option B is a strong distractor that seems correct but incorrectly equates crystal structure with unit cells rather than atomic arrangement. Option C exploits nuclear physics confusion by incorrectly assigning electron density to crystal structure. Option D creates a false dichotomy by oversimplifying property determination, which actually involves both structures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1571, "question": "2. Space group", "answer": "A symmetry group formed by the combination of all symmetry elements (including microscopic symmetry elements) in a crystal structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Space group\"进行文字解释和论述，答案是一个详细的定义，不需要选择、判断或计算 | 知识层次: 题目考查对空间群这一基本概念的定义记忆和理解，属于晶体学中的基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。虽然题目涉及空间群的定义，但只需要记忆和理解对称元素组合形成空间群的基本概念，不需要进行复杂的分析或比较多个概念。因此，难度属于中等偏下。", "convertible": true, "correct_option": "A symmetry group formed by the combination of all symmetry elements (including microscopic symmetry elements) in a crystal structure.", "choice_question": "Which of the following best describes a space group?", "conversion_reason": "The answer is a standard definition of a space group, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A symmetry group formed by the combination of all symmetry elements (including microscopic symmetry elements) in a crystal structure", "B": "The group of crystallographic point operations that leave at least one point fixed in a crystal lattice", "C": "The mathematical description of atomic arrangements in amorphous materials", "D": "A set of symmetry operations that describe the external morphology of crystals" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines space groups as encompassing all symmetry elements including translations (microscopic symmetry). B describes point groups, a common confusion. C is a trap for those confusing crystalline/amorphous structures. D describes morphological symmetry, a surface-level understanding trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3493, "question": "What are the characteristics of cast iron and carbon steel in terms of mechanical properties?", "answer": "Cast iron has low tensile strength, compressive strength similar to steel with the same matrix, and poor plasticity and toughness; carbon steel has higher strength and better plasticity and toughness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述铸铁和碳钢在机械性能方面的特点，答案提供了详细的文字描述而非选择、判断或计算。 | 知识层次: 题目考查对铸铁和碳钢机械性能基本特征的记忆和理解，属于基础概念层面的知识。 | 难度: 该题目在选择题型中属于中等偏下难度。虽然需要考生同时掌握铸铁和碳钢的机械性能特点（包括抗拉强度、抗压强度、塑性、韧性等），但题目仅要求对两种材料的基本特性进行对比描述，不涉及复杂的概念体系或深入的分析。正确选项直接给出了两种材料的特性对比，属于概念解释和描述层面的知识，符合等级2的标准。", "convertible": true, "correct_option": "Cast iron has low tensile strength, compressive strength similar to steel with the same matrix, and poor plasticity and toughness; carbon steel has higher strength and better plasticity and toughness.", "choice_question": "Which of the following correctly describes the characteristics of cast iron and carbon steel in terms of mechanical properties?", "conversion_reason": "The answer is a standard description of the mechanical properties of cast iron and carbon steel, which can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cast iron has low tensile strength, compressive strength similar to steel with the same matrix, and poor plasticity and toughness; carbon steel has higher strength and better plasticity and toughness.", "B": "Cast iron exhibits higher tensile strength than carbon steel due to its graphite inclusions, while maintaining comparable compressive strength and superior impact toughness.", "C": "Both cast iron and carbon steel show nearly identical stress-strain curves in tension, with cast iron having slightly better ductility owing to its heterogeneous microstructure.", "D": "Carbon steel demonstrates lower yield strength but higher strain hardening capacity compared to cast iron, which shows brittle fracture behavior under all loading conditions." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the mechanical properties: cast iron's low tensile strength and poor plasticity due to graphite flakes, while maintaining compressive strength similar to steel matrix. Option B incorrectly suggests higher tensile strength and toughness in cast iron - graphite actually reduces these properties. Option C falsely claims similar tensile behavior and better ductility in cast iron. Option D is wrong about carbon steel's lower yield strength and cast iron's universal brittleness (some grades show limited plasticity).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2929, "question": "In substitutional solid solution alloys, the diffusion of solute atoms is achieved through . (A) Atomic exchange mechanism (B) Interstitial diffusion mechanism (C) Vacancy mechanism", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（A、B、C）中选择关于置换固溶体中溶质原子扩散机制的正确描述 | 知识层次: 题目考查的是对置换固溶体中溶质原子扩散机制的基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要学生对固溶体扩散机制有一定的理解和辨析能力，能够区分原子交换机制、间隙扩散机制和空位机制。学生需要掌握这些机制的基本定义和特点，才能正确选择答案。因此，该题目属于等级2，需要概念理解和简单辨析。", "convertible": true, "correct_option": "C", "choice_question": "In substitutional solid solution alloys, the diffusion of solute atoms is achieved through .", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Collective oscillation of electron clouds", "B": "Direct interstitial hopping between lattice sites", "C": "Vacancy-mediated atomic exchange", "D": "Grain boundary sliding mechanism" }, "correct_answer": "C", "explanation": "The correct answer is C because substitutional diffusion fundamentally requires vacancies for solute atoms to move. Option A exploits confusion with plasmonic phenomena in metals. Option B is a strong distractor as it describes interstitial diffusion which is mechanistically different. Option D targets confusion with high-temperature deformation mechanisms. Advanced AI might incorrectly select B due to oversimplified atomic movement models.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 471, "question": "Coordination polyhedron", "answer": "The polyhedron formed by connecting the centers of atoms or ions directly bonded to a central atom or ion is called the coordination polyhedron of that atom or ion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Coordination polyhedron\"进行定义和解释，答案以文字形式给出，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对\"coordination polyhedron\"这一基本概念的定义记忆和理解，不涉及应用或分析过程 | 难度: 在选择题型中，该题目仅考察对\"配位多面体\"这一基础概念的定义记忆，属于最基础的知识层次。题目仅要求识别正确描述定义的正确选项，无需解释或分析概念之间的关系，解题步骤简单直接，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The polyhedron formed by connecting the centers of atoms or ions directly bonded to a central atom or ion is called the coordination polyhedron of that atom or ion.", "choice_question": "Which of the following best describes a coordination polyhedron?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The polyhedron formed by connecting the centers of atoms or ions directly bonded to a central atom or ion", "B": "The geometric shape formed by the outermost electron orbitals of a coordination complex", "C": "The polyhedron defined by the Voronoi tessellation around a central atom in a crystal lattice", "D": "The spatial arrangement of all atoms within the first Brillouin zone of a coordination compound" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines the coordination polyhedron as the geometric arrangement of ligands around a central atom. Option B exploits the cognitive bias of associating polyhedrons with electron orbitals rather than atomic positions. Option C uses the advanced concept of Voronoi tessellation which is related but not equivalent to coordination polyhedrons. Option D creates confusion by mixing coordination chemistry with Brillouin zone concepts from solid state physics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1059, "question": "Critical nucleus", "answer": "Critical nucleus: In a metal liquid, an embryo with a radius larger than the critical radius rk can stably grow and is called a critical nucleus.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Critical nucleus\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对\"Critical nucleus\"这一基本概念的定义和解释，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于概念解释和描述难度。虽然涉及基础概念记忆，但需要理解并描述\"critical nucleus\"的定义及其在金属液体中的行为，比单纯记忆定义稍复杂，但不需要进行多概念比较或复杂体系阐述。", "convertible": true, "correct_option": "In a metal liquid, an embryo with a radius larger than the critical radius rk can stably grow and is called a critical nucleus.", "choice_question": "Which of the following best describes a critical nucleus in a metal liquid?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct description as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In a metal liquid, an embryo with a radius larger than the critical radius rk can stably grow and is called a critical nucleus", "B": "The smallest crystalline structure that can form spontaneously in a supercooled liquid without dissolving back", "C": "A nucleus that has reached the minimum Gibbs free energy required for stable growth in a solidifying alloy", "D": "The first ordered atomic arrangement that appears during liquid-to-solid transformation in metals" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines the critical nucleus in terms of the critical radius concept in nucleation theory. Option B is misleading by suggesting spontaneous formation without considering the energy barrier. Option C incorrectly focuses on Gibbs free energy minimum rather than the critical size threshold. Option D describes general nucleation but fails to specify the critical size aspect that distinguishes a critical nucleus.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4371, "question": "Name the microstructural products of 4340 alloy steel specimens that are first completely transformed to austenite, then cooled to room temperature at a rate of 10°C/s.", "answer": "only martensite forms.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述4340合金钢在特定冷却条件下的微观结构产物，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求考生理解4340合金钢的微观结构转变过程，并应用连续冷却转变图（CCT图）的知识来判断在特定冷却速率（10°C/s）下形成的产物。这需要将多个概念（奥氏体化、冷却速率、马氏体转变）关联起来进行分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解4340合金钢的相变行为、冷却速率对微观结构的影响以及马氏体形成的条件。虽然题目给出了具体的冷却速率（10°C/s），但学生需要知道这一速率足以避免其他相（如珠光体或贝氏体）的形成，从而仅形成马氏体。这涉及多个概念的关联和综合分析，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "only martensite forms", "choice_question": "What are the microstructural products of 4340 alloy steel specimens that are first completely transformed to austenite, then cooled to room temperature at a rate of 10°C/s?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "only martensite forms", "B": "martensite with retained austenite", "C": "bainite and martensite", "D": "pearlite and martensite" }, "correct_answer": "A", "explanation": "The correct answer is A because at a cooling rate of 10°C/s, 4340 steel exceeds the critical cooling rate for full martensitic transformation without forming other phases. Option B is a common misconception due to incomplete transformation knowledge in some alloys. Option C exploits the bainite formation temperature range confusion. Option D triggers pearlite formation intuition from slower cooling rates.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4253, "question": "The diffusion coefficients for silver in copper are given at two temperatures: T(°C) = 650, D(m2/s) = 5.5 × 10^-16 and T(°C) = 900, D(m2/s) = 1.3 × 10^-13. What is the magnitude of D at 875°C?", "answer": "the magnitude of d at 875°c is 8.3 × 10^-14 m2/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的扩散系数和温度数据，应用阿伦尼乌斯方程或其他相关公式进行计算，以求出在特定温度下的扩散系数。答案是一个具体的数值结果，这表明需要进行数值计算和公式应用。 | 知识层次: 题目需要应用扩散系数的阿伦尼乌斯方程进行多步计算，涉及温度转换、对数运算和指数运算，需要综合分析给定的数据点并求解未知参数，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解扩散系数与温度的关系，应用阿伦尼乌斯方程进行多步计算，并综合分析给定数据来求解未知温度下的扩散系数。虽然题目提供了必要的数据，但解题过程涉及对数运算和代数操作，对学生的计算能力和概念掌握有一定要求。", "convertible": true, "correct_option": "8.3 × 10^-14 m2/s", "choice_question": "The diffusion coefficients for silver in copper are given at two temperatures: T(°C) = 650, D(m2/s) = 5.5 × 10^-16 and T(°C) = 900, D(m2/s) = 1.3 × 10^-13. What is the magnitude of D at 875°C?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.3 × 10^-14 m2/s", "B": "1.3 × 10^-13 m2/s", "C": "5.5 × 10^-16 m2/s", "D": "3.7 × 10^-14 m2/s" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Arrhenius equation for diffusion, which requires converting temperatures to Kelvin and solving the system of equations for activation energy and pre-exponential factor. Option B is a direct data point from the problem (at 900°C) designed to exploit the AI's tendency to select given values. Option C is the lower temperature data point, exploiting recency bias. Option D is a carefully calculated wrong answer using incorrect temperature conversion (forgetting to add 273 to Celsius), targeting a common calculation mistake.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2710, "question": "Given that W at 20℃ has one vacancy per 10^23 unit cells, and each unit cell contains 2 W atoms, calculate the vacancy concentration C at 20℃.", "answer": "C_20 = 1 / (2 × 10^23) = 5 × 10^-24.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及具体的数学运算和单位转换，最终给出一个数值结果。 | 知识层次: 题目仅涉及基本公式应用和简单计算，直接套用给定的数值进行计算即可，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用一个基本公式（空缺浓度计算）并进行简单的数值计算。解题步骤非常直接，没有涉及多个公式的组合或复杂的概念分析，因此属于单一公式直接计算的难度等级1。", "convertible": true, "correct_option": "5 × 10^-24", "choice_question": "Given that W at 20℃ has one vacancy per 10^23 unit cells, and each unit cell contains 2 W atoms, the vacancy concentration C at 20℃ is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5 × 10^-24", "B": "1 × 10^-23", "C": "2 × 10^-23", "D": "5 × 10^-23" }, "correct_answer": "A", "explanation": "The correct answer is A (5 × 10^-24) because vacancy concentration is calculated as (number of vacancies)/(total number of atomic sites). Here, 1 vacancy exists per 10^23 unit cells, with each unit cell containing 2 atoms, so total atomic sites = 2 × 10^23. Thus, C = 1/(2 × 10^23) = 5 × 10^-24. Option B (1 × 10^-23) is a trap for those who forget to account for 2 atoms per unit cell. Option C (2 × 10^-23) incorrectly uses the reciprocal relationship. Option D (5 × 10^-23) is an order-of-magnitude trap that might catch those who miscalculate the exponent.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1542, "question": "Give the one-dimensional form of Fick's second law and explain the meaning and units of each physical quantity in the formula", "answer": "The one-dimensional form of Fick's second law is: ∂C/∂t = D·∂²C/∂x². In the formula, C (g/cm³) is the concentration; D (cm²/s) is the diffusion coefficient; t (s) is the time; x (cm) is the distance.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求给出Fick's第二定律的一维形式，并解释公式中每个物理量的含义和单位。这需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对Fick's第二定律一维形式的基本概念记忆，包括公式中各物理量的含义和单位，属于基础概念的记忆和理解层面。 | 难度: 在选择题型中，该题目要求考生不仅记忆Fick's第二定律的一维形式，还需要解释公式中各个物理量的含义和单位。这属于概念解释和描述的层次，比单纯的定义简答（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。因此，该题目在选择题型内属于中等难度（等级2）。", "convertible": true, "correct_option": "The one-dimensional form of Fick's second law is: ∂C/∂t = D·∂²C/∂x². In the formula, C (g/cm³) is the concentration; D (cm²/s) is the diffusion coefficient; t (s) is the time; x (cm) is the distance.", "choice_question": "Which of the following correctly represents the one-dimensional form of Fick's second law and explains the meaning and units of each physical quantity in the formula?", "conversion_reason": "The answer is a standard explanation of Fick's second law, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "∂C/∂t = D·∂²C/∂x², where C (g/cm³) is concentration, D (cm²/s) is diffusivity, t (s) is time, x (cm) is distance", "B": "∂C/∂t = D·∂C/∂x, where C (mol/m³) is concentration, D (m²/s) is diffusivity, t (s) is time, x (m) is distance", "C": "∂²C/∂t² = D·∂²C/∂x², where C (wt%) is concentration, D (mm²/s) is diffusivity, t (hr) is time, x (mm) is distance", "D": "∂C/∂x = D·∂²C/∂t², where C (at%) is concentration, D (μm²/s) is diffusivity, t (min) is time, x (μm) is distance" }, "correct_answer": "A", "explanation": "Option A is correct as it shows the proper second-order partial differential form with consistent units. Option B incorrectly uses Fick's first law form. Option C introduces a second time derivative which doesn't exist in diffusion equations. Option D reverses the spatial and temporal derivatives. The distractors exploit common confusions between Fick's first/second laws, time derivative orders, and unit system inconsistencies that may trigger incorrect pattern matching in AI models.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 963, "question": "According to the size of defects relative to the crystal dimensions and their range of influence, into which categories can defects be classified? Briefly describe the characteristics of these categories.", "answer": "There are four categories: Point defects: Very small in all three dimensions, such as solute atoms, interstitial atoms, and vacancies. Line defects: Very small in two dimensions, but large in the third dimension, potentially extending through the entire crystal, referring to dislocations. Planar defects: Very small in one dimension but large in the other two dimensions, such as grain boundaries and phase boundaries. Volume defects: Relatively large in all three dimensions but not excessively so, such as second-phase particles and microscopic voids.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对缺陷进行分类并简要描述各类别的特征，答案以文字解释和论述的形式呈现，符合简答题的特点。 | 知识层次: 题目考查对晶体缺陷分类的基本概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目要求考生理解和描述四种缺陷分类及其特征，属于概念解释和描述的层次。虽然需要记忆和掌握多个概念，但题目提供了明确的分类和特征描述，解题步骤相对直接，不需要复杂的分析或比较。因此，在选择题型内属于中等难度（等级2）。", "convertible": true, "correct_option": "There are four categories: Point defects: Very small in all three dimensions, such as solute atoms, interstitial atoms, and vacancies. Line defects: Very small in two dimensions, but large in the third dimension, potentially extending through the entire crystal, referring to dislocations. Planar defects: Very small in one dimension but large in the other two dimensions, such as grain boundaries and phase boundaries. Volume defects: Relatively large in all three dimensions but not excessively so, such as second-phase particles and microscopic voids.", "choice_question": "According to the size of defects relative to the crystal dimensions and their range of influence, into which categories can defects be classified?", "conversion_reason": "The answer is a standard classification with clear categories and descriptions, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Point defects, line defects, surface defects, and bulk defects", "B": "Atomic defects, linear defects, planar defects, and volumetric defects", "C": "Vacancies, dislocations, grain boundaries, and precipitates", "D": "Zero-dimensional, one-dimensional, two-dimensional, and three-dimensional defects" }, "correct_answer": "D", "explanation": "The correct classification is based on the dimensionality of defects (0D, 1D, 2D, 3D) relative to the crystal structure. Option A incorrectly uses 'surface' and 'bulk' which are not standard classifications. Option B mixes defect types with their dimensional classification. Option C lists specific defect examples rather than categories. Advanced AIs may choose B due to its seemingly technical terminology, but it misrepresents the standard classification system.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4679, "question": "Compare thermoplastic and thermosetting polymers according to possible molecular structures.", "answer": "Thermoplastic polymers have linear and branched structures, while for thermosetting polymers, the structures will normally be network or crosslinked.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较两种聚合物的分子结构，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对热塑性聚合物和热固性聚合物分子结构的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目要求考生比较热塑性聚合物和热固性聚合物的分子结构，并选择正确的描述。虽然涉及两个概念的比较，但知识点相对基础，属于定义和分类的记忆性知识。解题步骤较为直接，只需识别并匹配正确的结构特征即可，不需要复杂的分析或推理过程。因此，在选择题型中属于中等偏下的难度等级。", "convertible": true, "correct_option": "Thermoplastic polymers have linear and branched structures, while for thermosetting polymers, the structures will normally be network or crosslinked.", "choice_question": "Compare thermoplastic and thermosetting polymers according to possible molecular structures. Which of the following is correct?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct comparison.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermoplastic polymers have linear and branched structures, while thermosetting polymers have network or crosslinked structures", "B": "Both thermoplastic and thermosetting polymers can form crosslinked structures, but thermosets have higher crosslink density", "C": "Thermosetting polymers exhibit only linear structures prior to curing, then form branched structures", "D": "Thermoplastic polymers always maintain linear structures, while thermosets alternate between linear and network structures" }, "correct_answer": "A", "explanation": "The correct answer is A because thermoplastics are characterized by linear or branched chains that can be remelted, while thermosets form permanent crosslinked networks. Option B is misleading because thermoplastics generally do not form crosslinks. Option C exploits the curing misconception by suggesting incorrect structural evolution. Option D creates confusion by implying structural alternation in thermosets, which is impossible after curing.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3007, "question": "ABS plastic is an engineering material with excellent comprehensive properties.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（ABS plastic is an engineering material with excellent comprehensive properties），并要求判断其正确性（答案：√），符合判断题的特征。 | 知识层次: 题目考查对ABS塑料基本特性的记忆和理解，属于基础概念记忆范畴 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆ABS塑料的基本定义和特性即可做出正确选择，无需深入理解或分析复杂概念。", "convertible": true, "correct_option": "√", "choice_question": "ABS plastic is an engineering material with excellent comprehensive properties.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ABS plastics exhibit identical mechanical properties regardless of their composition ratios.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "ABS (Acrylonitrile Butadiene Styrene) is a terpolymer whose mechanical properties vary significantly depending on the relative proportions of its three monomers. The statement contains an absolute claim ('All') that is incorrect, as properties like impact strength, heat resistance, and rigidity can be tailored by adjusting composition ratios. This tests understanding of material property dependence on microstructure and composition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3497, "question": "How to distinguish between 45 steel and HT150 metals through macroscopic fracture analysis", "answer": "Macroscopic fracture analysis", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来区分两种金属材料，答案形式为文字描述而非选择、判断或计算。 | 知识层次: 题目要求通过宏观断口分析区分45钢和HT150金属，这需要理解两种材料的断口特征（如45钢的韧性断裂和HT150的脆性断裂），并能将这些特征与实际观察结果关联起来进行分析。虽然不涉及复杂计算，但需要综合运用材料科学知识进行判断，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解金属材料的宏观断裂特征（如45钢的韧性断裂和HT150的脆性断裂表现），并能通过断口形貌（纤维状/结晶状）进行区分。题目要求将材料性能知识与实际观察技能结合，但无需多角度或深度关联性分析。", "convertible": true, "correct_option": "Macroscopic fracture analysis", "choice_question": "How can you distinguish between 45 steel and HT150 metals?", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by asking for the correct method among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Observing the color difference in fracture surfaces under UV light", "B": "Measuring the Vickers hardness at identical indentation loads", "C": "Comparing the fracture surface roughness with profilometry", "D": "Analyzing the acoustic emission frequency during fracture" }, "correct_answer": "C", "explanation": "Correct answer C is based on the fundamental difference in fracture mechanisms between ductile steel (45 steel shows dimpled rupture) and brittle cast iron (HT150 shows cleavage facets). Option A exploits color perception bias but both materials oxidize similarly. Option B uses hardness similarity trap (both ~200HB) but ignores microstructure differences. Option D leverages advanced NDT method bias that's actually insensitive to material type.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4626, "question": "Briefly explain why some transparent materials appear colored while others are colorless.", "answer": "For a transparent material that appears colorless, any absorption within its interior is the same for all visible wavelengths. On the other hand, if there is any selective absorption of visible light (usually by electron excitations), the material will appear colored, its color being dependent on the frequency distribution of the transmitted light beam.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要解释透明材料为何呈现有色或无色，需要文字解释和论述，答案也提供了详细的文字说明，符合简答题的特征。 | 知识层次: 题目考查对透明材料颜色现象的基本原理的理解和记忆，涉及吸收光谱和电子激发等基础概念，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然涉及基础概念记忆，但需要考生理解并解释透明材料颜色现象背后的基本原理（选择性吸收与均匀吸收的区别）。题目要求考生能够区分两种不同光学现象的本质原因，并正确描述颜色产生的机制，这比单纯记忆定义（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "For a transparent material that appears colorless, any absorption within its interior is the same for all visible wavelengths. On the other hand, if there is any selective absorption of visible light (usually by electron excitations), the material will appear colored, its color being dependent on the frequency distribution of the transmitted light beam.", "choice_question": "Why do some transparent materials appear colored while others are colorless?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The material's refractive index varies significantly with wavelength, causing selective light scattering", "B": "The presence of transition metal ions creates d-d electron transitions that absorb specific visible wavelengths", "C": "The bandgap energy corresponds exactly to ultraviolet frequencies, leaving all visible light unaffected", "D": "Random atomic vacancies in the crystal lattice preferentially scatter shorter wavelengths" }, "correct_answer": "B", "explanation": "Correct answer B identifies the most common mechanism through transition metal ion electron transitions. Option A describes dispersion (wavelength-dependent refraction) which causes chromatic aberration but not coloration. Option C is a trap for those who know UV absorption but don't realize complete visible transparency would result. Option D sounds plausible but describes Rayleigh scattering which occurs in imperfect materials, not perfect crystals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3707, "question": "A ceramic part made of MgO is sintered successfully at 1700 degrees C in 90 minutes. To minimize thermal stresses during the process, we plan to reduce the temperature to 1500 degrees C. Which will limit the rate at which sintering can be done: diffusion of magnesium ions or diffusion of oxygen ions?", "answer": "diffusion of oxygen is the slower of the two, due to the larger ionic radius of the oxygen.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释哪种离子扩散会限制烧结速率，并需要提供文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目要求分析在烧结过程中不同离子扩散速率对烧结速率的影响，需要综合运用材料科学中的扩散理论、离子半径对扩散速率的影响以及烧结动力学等知识，进行推理分析和机理解释。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "diffusion of oxygen ions", "choice_question": "A ceramic part made of MgO is sintered successfully at 1700 degrees C in 90 minutes. To minimize thermal stresses during the process, we plan to reduce the temperature to 1500 degrees C. Which will limit the rate at which sintering can be done:", "conversion_reason": "The original short answer question can be converted into a multiple-choice question because the answer is a specific concept (diffusion of oxygen ions) that can be presented as one of the options. The question can be rephrased to fit a multiple-choice format by asking which factor limits the sintering rate.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diffusion of magnesium ions", "B": "Diffusion of oxygen ions", "C": "Grain boundary migration", "D": "Surface energy reduction" }, "correct_answer": "B", "explanation": "In MgO sintering, oxygen ion diffusion is the rate-limiting step due to its larger ionic radius and higher activation energy compared to magnesium ions. Option A exploits the cognitive bias that smaller magnesium ions would diffuse slower. Option C targets the misconception that grain boundary movement controls sintering kinetics. Option D uses the intuitive but incorrect assumption that surface energy reduction is the limiting factor.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2021, "question": "Calculate the distance between the center of a sodium ion and the third nearest Cl− ion in NaCl (given the radii of Na+ and Cl− are 0.097nm and 0.181nm, respectively).", "answer": "0.622nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算钠离子与第三近邻氯离子之间的距离），并给出了具体的离子半径数据，需要使用公式和计算步骤来得出最终答案0.622nm。 | 知识层次: 题目需要理解NaCl晶体结构，应用离子半径和晶体几何关系进行多步计算，涉及空间几何概念和数值计算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构的基本概念（如离子半径、晶格排列），并能够进行多步计算（确定晶格常数、计算第三近邻距离）。虽然题目给出了离子半径，但需要考生综合运用这些信息来推导正确答案，涉及概念关联和综合分析能力。", "convertible": true, "correct_option": "0.622nm", "choice_question": "What is the distance between the center of a sodium ion and the third nearest Cl− ion in NaCl (given the radii of Na+ and Cl− are 0.097nm and 0.181nm, respectively)?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.622nm", "B": "0.486nm", "C": "0.278nm", "D": "0.414nm" }, "correct_answer": "A", "explanation": "The correct answer is 0.622nm, calculated as the sum of the ionic radii (0.097nm + 0.181nm) multiplied by √3 (the distance factor for the third nearest neighbor in an FCC structure). Option B (0.486nm) is the distance to the second nearest neighbor, a common mistake from confusing coordination shells. Option C (0.278nm) is simply the sum of ionic radii, representing first nearest neighbor distance. Option D (0.414nm) is the second nearest neighbor distance in BCC structure, a trap for those misremembering crystal structures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2994, "question": "Thermoplastics mainly have (4) molecular chains.", "answer": "(4) linear", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的单词（linear）来描述热塑性塑料的分子链结构，属于简短的文字回答形式，而非从多个选项中选择或判断对错。 | 知识层次: 题目考查热塑性塑料分子链结构的基本概念记忆，属于定义和分类的基础知识范畴，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对热塑性塑料分子链结构的基础定义记忆（线性结构），属于最基础的概念识别层级，无需解释或分析步骤。", "convertible": true, "correct_option": "linear", "choice_question": "Thermoplastics mainly have which type of molecular chains?", "conversion_reason": "The answer is a standard term (linear) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "linear", "B": "cross-linked", "C": "branched", "D": "dendritic" }, "correct_answer": "A", "explanation": "Thermoplastics primarily consist of linear molecular chains that allow for reversible melting upon heating. Option B (cross-linked) is a thermoset characteristic that creates irreversible bonds. Option C (branched) exploits the common knowledge that some polymers have branches, but thermoplastics are predominantly linear. Option D (dendritic) uses an advanced polymer structure that exists but is irrelevant to standard thermoplastics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4894, "question": "(a) Write an expression for the modulus of elasticity for a hybrid composite in which all fibers of both types are oriented in the same direction.", "answer": "the expression for the modulus of elasticity for a hybrid composite with all fibers aligned in the same direction is: e_cl = e_m v_m + e_f1 v_f1 + e_f2 v_f2", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求写出混合复合材料弹性模量的表达式，需要文字解释和论述，答案是一个公式表达式，属于简答题类型。 | 知识层次: 题目要求写出混合复合材料弹性模量的表达式，这属于基本公式的直接应用。虽然涉及多个组分（基体和两种纤维），但只需简单地将各组分模量按其体积分数加权求和，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单应用过程描述。题目要求直接套用已知的混合复合材料弹性模量公式，无需复杂的分析或计算步骤。考生只需识别并应用基本公式即可得出正确答案，属于基础难度水平。", "convertible": true, "correct_option": "e_cl = e_m v_m + e_f1 v_f1 + e_f2 v_f2", "choice_question": "What is the expression for the modulus of elasticity for a hybrid composite in which all fibers of both types are oriented in the same direction?", "conversion_reason": "The answer is a standard expression, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "E_cl = E_m V_m + E_f1 V_f1 + E_f2 V_f2", "B": "E_cl = (E_f1 V_f1 + E_f2 V_f2) / (V_f1 + V_f2)", "C": "E_cl = E_m V_m + (E_f1 + E_f2)(V_f1 + V_f2)", "D": "E_cl = (E_m V_m + E_f1 V_f1 + E_f2 V_f2) / (V_m + V_f1 + V_f2)" }, "correct_answer": "A", "explanation": "The correct answer A follows the rule of mixtures for hybrid composites with unidirectional fibers. Option B incorrectly averages the fiber moduli, a common mistake when forgetting the matrix contribution. Option C creates a false intuition by grouping fiber terms incorrectly. Option D mimics an average calculation, exploiting the cognitive bias towards normalized values. Advanced AIs may choose B or D due to their mathematical symmetry, while humans might favor C for its deceptive grouping logic.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1928, "question": "Given a powder compact with an average particle size of 5μm, after sintering for 2 hours, the neck growth ratio x/r=0.1. If grain growth is not considered, how much time is required to sinter the compact to a neck growth ratio x/r=0.2 through diffusion mass transport?", "answer": "Diffusion mass transport formula: x/r = k r^(-3/5) t^(1/5). Substituting x/r=0.1, r=5μm, t=2h to solve for k: 0.1 = k (5)^(-3/5) (2)^(1/5), yielding k. Then substituting x/r=0.2, r=5μm and k to solve for t: 0.2 = k (5)^(-3/5) t^(1/5), yielding t=64h. Diffusion mass transport requires 64h.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，通过给定的公式和条件求解所需时间，答案也是具体的数值结果。 | 知识层次: 题目涉及多步计算和公式应用，需要理解扩散质量传输公式并正确代入数值求解常数k，然后再次应用公式求解新的时间t。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力和概念关联。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散质量传输公式并进行多步计算。题目要求考生首先根据已知条件求解常数k，然后利用k值计算新的时间t。虽然计算步骤明确，但涉及指数运算和代数求解，对考生的计算能力和公式应用能力有一定要求。", "convertible": true, "correct_option": "64h", "choice_question": "Given a powder compact with an average particle size of 5μm, after sintering for 2 hours, the neck growth ratio x/r=0.1. If grain growth is not considered, how much time is required to sinter the compact to a neck growth ratio x/r=0.2 through diffusion mass transport?", "conversion_reason": "The calculation leads to a specific numerical answer (64h), which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "64h", "B": "8h", "C": "32h", "D": "16h" }, "correct_answer": "A", "explanation": "The correct answer is 64h because neck growth in sintering follows a power law relationship (x/r)^n = Kt, where n=5 for diffusion-controlled sintering. Doubling the neck growth ratio from 0.1 to 0.2 requires 2^5=32 times longer, hence 2h*32=64h. Option B (8h) is a linear time scaling trap. Option C (32h) results from incorrectly using n=4. Option D (16h) is a square relationship trap (n=2).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2026, "question": "Calculate the distance between the centers of sodium ions at the nearest identical positions in NaCl (given the radii of Na+ and Cl− are 0.097nm and 0.181nm, respectively).", "answer": "0.393nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算钠离子之间的距离），并给出了具体的数值答案（0.393nm），这符合计算题的特征。 | 知识层次: 题目主要考查基本公式应用和简单计算，仅需知道离子半径和晶体结构的基本概念，通过简单加法即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算NaCl晶体中最近邻钠离子中心之间的距离，只需应用简单的晶体学距离公式（即离子半径之和的两倍），无需多个步骤或复杂推理。给定离子半径后，计算过程直接且明确，属于基础级别的应用。", "convertible": true, "correct_option": "0.393nm", "choice_question": "What is the distance between the centers of sodium ions at the nearest identical positions in NaCl (given the radii of Na+ and Cl− are 0.097nm and 0.181nm, respectively)?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.393nm", "B": "0.278nm", "C": "0.556nm", "D": "0.181nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.393nm) because in NaCl structure, the distance between nearest identical Na+ ions is the face diagonal of the unit cell, which is √2 times the lattice parameter (a=2(r_Na+ + r_Cl-)=0.556nm). The interference strategies are: B (0.278nm) exploits the cognitive bias of simply adding ionic radii (0.097+0.181), C (0.556nm) traps those who confuse Na+-Na+ distance with lattice parameter, and D (0.181nm) targets those who mistake the Cl- radius for the interionic distance.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 953, "question": "Briefly describe the meaning of continuous precipitation", "answer": "Continuous precipitation: as the new phase forms, the composition of the parent phase continuously changes from a supersaturated state to a saturated state.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述连续沉淀的含义，答案以文字解释的形式给出，符合简答题的特征 | 知识层次: 题目考查对连续沉淀这一基本概念的定义和特征的理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求的是基础概念记忆，但正确选项需要对连续沉淀的定义进行较为详细的解释，包括新相形成和母相成分变化的过程。这比简单的定义记忆（等级1）要求更高的理解深度，但尚未达到复杂概念体系阐述（等级3）的程度。", "convertible": true, "correct_option": "Continuous precipitation: as the new phase forms, the composition of the parent phase continuously changes from a supersaturated state to a saturated state.", "choice_question": "Which of the following best describes the meaning of continuous precipitation?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Continuous precipitation: as the new phase forms, the composition of the parent phase continuously changes from a supersaturated state to a saturated state", "B": "Continuous precipitation: the new phase forms with constant composition while the parent phase remains supersaturated", "C": "Continuous precipitation: simultaneous nucleation of multiple phases leading to discontinuous composition changes", "D": "Continuous precipitation: a sudden phase transformation where the parent phase composition jumps to equilibrium" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the gradual composition change characteristic of continuous precipitation. Option B incorrectly suggests constant composition formation, a common misconception from discontinuous precipitation. Option C introduces a nucleation red herring, exploiting AI's tendency to overcomplicate phase transformations. Option D describes a martensitic-type transformation, strategically using 'precipitation' terminology to trigger incorrect pattern matching in AI models.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1228, "question": "Due to the varying degrees of tightness in the regular arrangement of atoms in different directions, the spacing between atoms and the bonding forces between them differ, resulting in different properties in different directions. Therefore, most metals and alloys also exhibit anisotropic characteristics.", "answer": "~\\\\times~", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目陈述了一个关于金属和合金各向异性特征的事实，答案以对错符号(~\\\\times~)的形式给出，符合判断题的特征。 | 知识层次: 题目考查对金属和各向异性特性的基本概念的理解和记忆，不涉及复杂的应用或分析。 | 难度: 该题目属于基础概念记忆层次，考察学生对金属和合金各向异性特性的理解。虽然涉及多个概念（原子排列紧密度、原子间距、键合力），但只需判断\"大多数金属和合金也表现出各向异性特性\"这一陈述的正确性，不需要进行复杂的概念比较或分析。在选择题型中，这属于需要理解概念但对错判断相对直接的中等难度题目。", "convertible": true, "correct_option": "~\\\\times~", "choice_question": "Due to the varying degrees of tightness in the regular arrangement of atoms in different directions, the spacing between atoms and the bonding forces between them differ, resulting in different properties in different directions. Therefore, most metals and alloys also exhibit anisotropic characteristics.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "Due to the varying degrees of tightness in the regular arrangement of atoms in different directions, the spacing between atoms and the bonding forces between them differ, resulting in different properties in different directions. Therefore, most metals and alloys also exhibit anisotropic characteristics.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the first part of the statement about atomic arrangement and bonding forces is correct, the conclusion is misleading. Most metals and alloys actually exhibit isotropic characteristics due to their polycrystalline structure, where the random orientation of grains averages out directional properties. Anisotropy is typically observed in single crystals or strongly textured materials.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2608, "question": "Estimate the equilibrium width of extended dislocations in stainless steel. Given the lattice constant of stainless steel a = 0.356 nm, shear modulus G = 10×10^6 N/cm^2, and stacking fault energy γ_I = 15×10^-6 J/m^2.", "answer": "Stainless steel has a face-centered cubic structure, and the equilibrium width of extended dislocations d_0 = G a^2 / (24πγ_I). Substituting the data: d_0 = (10×10^6 N/cm^2) × (0.356×10^-9 m)^2 / (24π × 15×10^-6 J/m^2) = 1.12×10^-5 m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和数据进行数值计算，最终得出一个具体的数值结果。解答过程涉及公式应用和单位转换，符合计算题的特征。 | 知识层次: 题目需要应用公式进行多步计算，涉及材料科学中的基本概念（如剪切模量、堆垛层错能）和公式推导，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如晶格常数、剪切模量、堆垛层错能）并进行多步骤计算。题目要求将给定的公式代入数值并进行单位换算，涉及中等应用层次的知识综合运用。虽然计算过程明确，但需要较强的概念关联能力和计算准确性。", "convertible": true, "correct_option": "1.12×10^-5 m", "choice_question": "Estimate the equilibrium width of extended dislocations in stainless steel. Given the lattice constant of stainless steel a = 0.356 nm, shear modulus G = 10×10^6 N/cm^2, and stacking fault energy γ_I = 15×10^-6 J/m^2. The equilibrium width of extended dislocations d_0 is:", "conversion_reason": "The calculation problem has a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct option among possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.12×10^-5 m", "B": "2.24×10^-5 m", "C": "5.6×10^-6 m", "D": "3.36×10^-5 m" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the formula d_0 = G*a/(2πγ_I), where all units must be properly converted. Option B doubles the correct value by incorrectly assuming the stacking fault energy should be halved. Option C is half the correct value due to misapplying the shear modulus conversion from N/cm^2 to N/m^2. Option D triples the correct value by erroneously incorporating the Burgers vector magnitude without proper normalization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2033, "question": "Describe the thermodynamic conditions of crystallization phase transition", "answer": "Analysis of the change in system free energy during crystallization phase transition shows that the thermodynamic condition for crystallization is ΔG<0. From the change in free energy per unit volume ΔGB=-LmΔT/Tm, it can be seen that only when ΔT>0 can ΔGg<0 be achieved. That is, only undercooling can make ΔG<0.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求描述结晶相变的热力学条件，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求分析结晶相变的热力学条件，涉及系统自由能变化和单位体积自由能变化的计算，需要理解并应用相关公式（ΔG<0和ΔGB=-LmΔT/Tm），同时需要关联概念（过冷度ΔT>0）来综合解释热力学条件。这属于中等应用层次，需要多步推理和概念关联。 | 难度: 在选择题中属于较高难度，题目要求分析结晶相变的热力学条件，涉及系统自由能变化、单位体积自由能变化以及过冷度等概念的综合理解和计算。需要考生能够将多个热力学概念关联起来，并进行多步推导和分析，才能得出正确的结论。这种题目不仅考察基本概念的理解，还要求考生能够进行综合分析和应用，因此在选择题型中属于较高难度。", "convertible": true, "correct_option": "Analysis of the change in system free energy during crystallization phase transition shows that the thermodynamic condition for crystallization is ΔG<0. From the change in free energy per unit volume ΔGB=-LmΔT/Tm, it can be seen that only when ΔT>0 can ΔGg<0 be achieved. That is, only undercooling can make ΔG<0.", "choice_question": "Which of the following describes the thermodynamic conditions of crystallization phase transition?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to ask for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ΔG<0 with ΔT>0, where ΔT is the undercooling below Tm", "B": "ΔH<0 at constant pressure, indicating exothermic crystallization", "C": "ΔS>0 at the melting temperature Tm", "D": "dG/dT=0 at the equilibrium melting point" }, "correct_answer": "A", "explanation": "The correct condition requires both ΔG<0 and undercooling (ΔT>0) as derived from ΔGB=-LmΔT/Tm. Option B exploits the common misconception that negative enthalpy change alone is sufficient, ignoring the need for undercooling. Option C traps those who confuse the entropy condition for melting (ΔS>0) with crystallization. Option D uses a true equilibrium condition but is irrelevant to the kinetic driving force for phase transition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 257, "question": "The diffusion coefficients of carbon in titanium at different temperatures were experimentally measured as 2×10−9cm2/s (736℃), 5×10−9cm2/s (782℃), and 1.3×10−8cm2/s (838℃). Given the activation energy for diffusion Q=2342787J/mol, determine the diffusion coefficient of carbon at 500℃.", "answer": "Substituting T=773K into D=D0exp(−Q/RT), with Q=2342787J/mol known, D0 is derived from D̅1=2×10−9cm2/s and T1=1009K as D0=2×10−9exp(2342787/(8.31×1009)). The calculated D500℃=1.87×10−10cm2/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的实验数据和公式（D=D0exp(−Q/RT)）进行数值计算，最终得出特定温度下的扩散系数。答案是一个具体的数值计算结果（D500℃=1.87×10−10cm2/s），符合计算题的特征。 | 知识层次: 题目需要应用扩散系数的阿伦尼乌斯公式进行多步计算，包括从已知数据推导前置因子D0，再计算新温度下的扩散系数。涉及公式变形、对数运算和单位转换，属于中等难度的应用题型。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散系数与温度的关系（阿伦尼乌斯方程），并能够正确代入已知条件进行多步计算。题目要求从实验数据推导出前置因子D0，再计算新温度下的扩散系数，涉及多个概念的综合应用和较复杂的计算步骤。虽然题目提供了部分关键参数，但解题过程仍需较强的综合分析能力。", "convertible": true, "correct_option": "1.87×10−10cm2/s", "choice_question": "Given the diffusion coefficients of carbon in titanium at different temperatures and the activation energy for diffusion Q=2342787J/mol, determine the diffusion coefficient of carbon at 500℃.", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.87×10−10cm2/s", "B": "3.42×10−9cm2/s", "C": "5.76×10−11cm2/s", "D": "2.14×10−8cm2/s" }, "correct_answer": "A", "explanation": "正确答案A通过阿伦尼乌斯方程计算得出，考虑了温度对扩散系数的指数影响。干扰项B利用了常见的高估温度影响的认知偏差，数值接近高温区间的测量值。干扰项C故意低估了扩散系数，利用了低温下扩散可能被过度抑制的直觉错误。干扰项D直接使用了最高温度下的测量值，忽略了温度降低对扩散系数的显著影响。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2801, "question": "Calculate the root mean square displacement $\\sqrt{\\overline{R_{n}^{2}}}$ of carbon atoms at $20\\%$, given the transition frequency is $r=2.1\\times10^{-9}/\\mathrm{s}$, the transition step length is $2.53\\times10^{-10}\\mathrm{m}$, and the time is $4\\mathrm{h}$.", "answer": "$\\sqrt{\\overline{R_{n}^{2}}}=\\sqrt{n}\\cdot r=\\sqrt{2.1\\times10^{-9}\\times4\\times3600}\\times2.53\\times10^{-10}=1.39\\times10^{-12}\\mathrm{m}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算，应用给定的公式和参数来求解碳原子的均方根位移，答案是一个具体的计算结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括时间单位的转换、频率与步长的综合应用，以及根均方位移公式的运用。虽然不涉及复杂的机理分析或创新设计，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散理论中的根均方位移概念，并正确应用公式进行多步骤计算。题目涉及时间单位转换、频率与步长的综合运用，以及平方根运算，但选项提供了明确的解题路径，减少了分析复杂度。", "convertible": true, "correct_option": "$1.39\\times10^{-12}\\mathrm{m}$", "choice_question": "Calculate the root mean square displacement $\\sqrt{\\overline{R_{n}^{2}}}$ of carbon atoms at $20\\%$, given the transition frequency is $r=2.1\\times10^{-9}/\\mathrm{s}$, the transition step length is $2.53\\times10^{-10}\\mathrm{m}$, and the time is $4\\mathrm{h}$. The correct value is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.39×10⁻¹² m", "B": "3.72×10⁻⁶ m", "C": "2.53×10⁻¹⁰ m", "D": "5.64×10⁻⁹ m" }, "correct_answer": "A", "explanation": "正确答案A是通过正确的扩散方程计算得出：√(n*l²) = √(6D*t)，其中D=(r*l²)/6。干扰项B是直接使用D=r*l²的错误计算，忽略了1/6因子。干扰项C是简单的步长值，利用了'看起来合理'的直觉陷阱。干扰项D是混淆了频率倒数与扩散时间的计算错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 688, "question": "Order-disorder transformation refers to the transformation between crystals and non-crystals", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（答案给出的是×表示错误），符合判断题的特征 | 知识层次: 题目考查对有序-无序转变这一基本概念的记忆和理解，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆\"有序-无序转变\"的定义即可判断对错，无需理解或分析复杂概念，解题步骤简单直接。", "convertible": true, "correct_option": "×", "choice_question": "Order-disorder transformation refers to the transformation between crystals and non-crystals", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials will eventually crystallize given sufficient time at temperatures below their glass transition temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many amorphous materials can crystallize over time (a process called devitrification), this is not universally true for all amorphous materials. Some materials like certain oxide glasses are extremely resistant to crystallization even over geological timescales. The statement incorrectly generalizes this behavior to all amorphous materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4249, "question": "The activation energy for the diffusion of carbon in chromium is 111,000 J/ mol. Calculate the diffusion coefficient at 1100 K\\left(827^{\\circ} C\\right), given that D at 1400 K\\left(1127^{\\circ} C\\right) is 6.25 × 10^{-11}{m}^{2} / s.", "answer": "the diffusion coefficient at 1100k is 4.6 × 10^{-12}{m}^{2} / s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的激活能和扩散系数数据，应用阿伦尼乌斯方程进行数值计算，最终得出特定温度下的扩散系数。答案是一个具体的数值计算结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要应用阿伦尼乌斯方程计算扩散系数，并理解温度对扩散系数的影响。虽然计算过程较为直接，但需要综合运用扩散理论和数学计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解阿伦尼乌斯方程的应用，并进行多步计算。题目要求考生能够将给定的温度、扩散系数和活化能关联起来，正确运用公式计算不同温度下的扩散系数。虽然题目提供了部分已知条件，但解题过程涉及对数运算和指数计算，对考生的综合计算能力和概念理解有一定要求。", "convertible": true, "correct_option": "4.6 × 10^{-12} m²/s", "choice_question": "The activation energy for the diffusion of carbon in chromium is 111,000 J/mol. Given that the diffusion coefficient at 1400 K is 6.25 × 10^{-11} m²/s, what is the diffusion coefficient at 1100 K?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as the correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.6 × 10^{-12} m²/s", "B": "1.2 × 10^{-11} m²/s", "C": "6.25 × 10^{-12} m²/s", "D": "3.8 × 10^{-13} m²/s" }, "correct_answer": "A", "explanation": "正确答案A是通过阿伦尼乌斯方程正确计算得出的扩散系数值。干扰项B利用了温度降低但扩散系数反而增大的反直觉陷阱，模拟了忽略指数关系的线性思维错误。干扰项C直接取用了原始数据的十分之一，利用了简单比例关系的认知偏差。干扰项D设计了一个过小的数值，利用了忽略预指数因子重要性的常见计算错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1014, "question": "Compare the activation energies of substitutional diffusion and interstitial diffusion.", "answer": "In comparison, the activation energy of interstitial diffusion is smaller.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较两种扩散方式的激活能，并给出解释性的答案，这属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对两种扩散方式（置换扩散和间隙扩散）激活能的基本概念记忆和理解，属于基础概念层面的比较。 | 难度: 在选择题中属于中等难度，需要理解并比较两种扩散机制（置换扩散和间隙扩散）的激活能概念，但不需要深入分析复杂的影响因素或推导过程。", "convertible": true, "correct_option": "The activation energy of interstitial diffusion is smaller.", "choice_question": "Compare the activation energies of substitutional diffusion and interstitial diffusion.", "conversion_reason": "The answer is a standard comparison statement that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy of interstitial diffusion is smaller due to smaller atomic displacement required", "B": "The activation energy of substitutional diffusion is smaller because it involves vacancy mechanisms", "C": "Both diffusion mechanisms have identical activation energies under equilibrium conditions", "D": "Substitutional diffusion has lower activation energy in FCC structures but higher in BCC structures" }, "correct_answer": "A", "explanation": "Correct answer A is based on the fundamental principle that interstitial atoms require less energy to move through crystal lattices compared to substitutional atoms which need to overcome vacancy formation energies. Option B reverses the correct relationship, exploiting the common misconception that vacancy-assisted diffusion should be easier. Option C creates a false equivalence trap by suggesting equilibrium conditions eliminate the difference. Option D introduces a structural dependency that doesn't fundamentally change the activation energy relationship between the two mechanisms, playing on AI's tendency to overgeneralize from specific material cases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4392, "question": "Compare white and nodular cast irons with respect to composition and heat treatment.", "answer": "White iron--2.5 to 4.0 wt% C and less than 1.0 wt% Si. No heat treatment; however, cooling is rapid during solidification. Nodular cast iron--2.5 to 4.0 wt% C, 1.0 to 3.0 wt% Si, and a small amount of Mg or Ce. A heat treatment at about 700°C may be necessary to produce a ferritic matrix.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种铸铁的成分和热处理方式，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求比较两种铸铁的成分和热处理工艺，涉及多个知识点的关联和综合分析，需要理解不同成分对材料性能的影响以及热处理工艺的选择依据，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解并比较两种铸铁的成分和热处理工艺，涉及多个概念的综合分析。虽然题目提供了具体数据，但考生仍需掌握相关知识才能正确理解和比较这些信息。", "convertible": true, "correct_option": "White iron--2.5 to 4.0 wt% C and less than 1.0 wt% Si. No heat treatment; however, cooling is rapid during solidification. Nodular cast iron--2.5 to 4.0 wt% C, 1.0 to 3.0 wt% Si, and a small amount of Mg or Ce. A heat treatment at about 700°C may be necessary to produce a ferritic matrix.", "choice_question": "Which of the following correctly compares white and nodular cast irons with respect to composition and heat treatment?", "conversion_reason": "The answer is a standard description that can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "White iron--2.5 to 4.0 wt% C and less than 1.0 wt% Si. No heat treatment; however, cooling is rapid during solidification. Nodular cast iron--2.5 to 4.0 wt% C, 1.0 to 3.0 wt% Si, and a small amount of Mg or Ce. A heat treatment at about 700°C may be necessary to produce a ferritic matrix.", "B": "White iron--1.0 to 2.5 wt% C and 1.0 to 3.0 wt% Si. Requires quenching to form martensite. Nodular cast iron--3.0 to 4.5 wt% C, less than 1.0 wt% Si, and added Ni. Annealing at 900°C is essential for ductility.", "C": "Both contain 2.5 to 4.0 wt% C, but white iron has higher Si (2.0-3.0 wt%) for graphite suppression. Nodular iron requires rapid cooling after adding Mg/Ce to prevent graphite formation.", "D": "White iron--3.0 to 4.5 wt% C with no Si, requiring tempering at 600°C. Nodular cast iron--identical composition to white iron but with slow cooling to form spheroidal graphite." }, "correct_answer": "A", "explanation": "Option A is correct as it accurately describes the higher carbon but lower silicon content in white iron that prevents graphite formation during rapid cooling, versus nodular iron's silicon and Mg/Ce addition that promotes spheroidal graphite, sometimes requiring ferritizing anneal. Option B reverses the Si contents and incorrectly suggests martensite formation in white iron. Option C falsely claims white iron has higher Si and that nodular iron needs rapid cooling. Option D is wrong about Si absence in white iron and identical compositions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3647, "question": "The density of a sample of HCP beryllium is 1.844 g/cm³ and the lattice parameters are a₀=0.22858 nm and c₀=0.35842 nm. Calculate the fraction of the lattice points that contain vacancies.", "answer": "0.0008", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算，涉及密度、晶格参数和空位分数的计算，需要应用相关公式和步骤来得出具体数值答案。答案是一个具体的数值（0.0008），符合计算题的特征。 | 知识层次: 题目需要应用HCP晶体结构的基本知识，进行多步计算（包括密度计算、晶格参数应用、空位分数计算等），涉及概念关联和综合分析，但不需要复杂的推理或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解六方密堆积（HCP）晶体的结构参数与密度的关系，并应用密度公式计算理论密度与实际密度的差异，进而推导空位分数。解题步骤包括：", "convertible": true, "correct_option": "0.0008", "choice_question": "The density of a sample of HCP beryllium is 1.844 g/cm³ and the lattice parameters are a₀=0.22858 nm and c₀=0.35842 nm. The fraction of the lattice points that contain vacancies is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0008", "B": "0.0024", "C": "0.0016", "D": "0.0004" }, "correct_answer": "A", "explanation": "The correct answer is A (0.0008) because it accurately reflects the calculated vacancy fraction based on the given HCP beryllium parameters. Option B (0.0024) is a cognitive bias trap that incorrectly assumes a linear relationship with the c/a ratio. Option C (0.0016) exploits a common calculation error where students forget to account for the 2-atom basis in HCP. Option D (0.0004) is designed to catch those who miscalculate by using only half the unit cell volume.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 495, "question": "The reason why the carbon solubility of austenite is higher than that of ferrite is that the interstitial spaces in the austenite crystal structure are larger.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性（√表示正确），这是典型的判断题特征 | 知识层次: 题目考查对奥氏体和铁素体晶体结构中碳溶解度的基本概念的理解，属于基础概念的记忆和简单理解范畴。 | 难度: 该题目属于基础概念正误判断题，仅需记忆奥氏体和铁素体的晶体结构差异这一基本原理即可作答。在选择题型中，这类仅涉及单一概念记忆的判断题属于最低难度等级。", "convertible": true, "correct_option": "√", "choice_question": "The reason why the carbon solubility of austenite is higher than that of ferrite is that the interstitial spaces in the austenite crystal structure are larger.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit higher hardness than all metallic materials under all conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While ceramics generally have higher hardness than metals, this is not an absolute rule. Some specially processed metals (like hardened tool steels) can surpass softer ceramics in hardness. Additionally, environmental conditions like temperature can affect material properties. The use of 'all' and 'under all conditions' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2133, "question": "What would be the result if carburizing of steel parts is not conducted in the γ phase region?", "answer": "If carburizing is not performed in the γ phase region, since the maximum carbon solubility (mass fraction) in α-Fe is only 0.0218%, for steel with a carbon mass fraction greater than 0.0218%, the carbon concentration gradient in the part during carburizing would be zero, making carburizing impossible; even for pure iron, when carburizing in the α phase region, the concentration gradient in the iron is very small, and a high carbon layer cannot be obtained on the surface. Additionally, due to the low temperature, the diffusion coefficient is also very small, making the carburizing process extremely slow and practically meaningless.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释在γ相区外进行钢件渗碳的结果，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释在非γ相区进行渗碳的后果，涉及对相图、扩散系数和浓度梯度的综合分析，需要深入理解材料科学中的相变和扩散机制，并进行推理分析。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解γ相区和α相区的碳溶解度差异，还需要综合运用扩散系数、浓度梯度等概念进行机理分析。正确选项涉及多个专业概念的联动解释（如碳溶解度限制、扩散动力学、相变条件等），需要考生具备将材料科学原理与工程实践相结合的复杂分析能力。这种在选择题中要求全面分析相变、扩散和工艺参数相互作用的题目，已经达到了选择题型中最高的认知要求层次。", "convertible": true, "correct_option": "If carburizing is not performed in the γ phase region, since the maximum carbon solubility (mass fraction) in α-Fe is only 0.0218%, for steel with a carbon mass fraction greater than 0.0218%, the carbon concentration gradient in the part during carburizing would be zero, making carburizing impossible; even for pure iron, when carburizing in the α phase region, the concentration gradient in the iron is very small, and a high carbon layer cannot be obtained on the surface. Additionally, due to the low temperature, the diffusion coefficient is also very small, making the carburizing process extremely slow and practically meaningless.", "choice_question": "What would be the result if carburizing of steel parts is not conducted in the γ phase region?", "conversion_reason": "The answer is a detailed explanation that can be directly used as a correct option in a multiple-choice question. The question can be kept as is, and the answer can be one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Carburizing would proceed normally but at a slower rate due to reduced diffusion coefficients", "B": "Surface decarburization would occur instead of carburization due to reverse carbon diffusion", "C": "Carbon solubility limit would be exceeded, causing graphite precipitation throughout the material", "D": "Martensite formation would occur spontaneously even without subsequent quenching" }, "correct_answer": "A", "explanation": "The correct answer is A because carburizing outside the γ phase region would indeed be extremely slow due to low carbon solubility in α-Fe and small diffusion coefficients, making the process practically ineffective. Option B exploits the common misconception about diffusion directionality. Option C uses the intuitive but incorrect expectation of exceeding solubility limits. Option D taps into the well-known association between carburizing and martensite formation, but incorrectly suggests it would occur without quenching.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4488, "question": "Is it possible to grind up and reuse polypropylene? Why or why not?", "answer": "Yes, it is possible to grind up and reuse polypropylene since it is a thermoplastic polymer, will soften when reheated, and, thus, may be remolded.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对是否可能研磨和再利用聚丙烯进行解释和论述，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对聚丙烯（polypropylene）基本特性的记忆和理解，即它是一种热塑性聚合物，可以通过加热软化并重新塑形。这属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（聚丙烯的可回收性），但需要考生理解并应用\"热塑性聚合物\"这一概念来解释其可回收原理。相比单纯记忆定义（等级1），该题要求考生能够将概念与具体材料特性联系起来进行解释（等级2）。但题目不需要分析复杂概念体系或进行多步骤推理（等级3），因此属于等级2难度。", "convertible": true, "correct_option": "Yes, it is possible to grind up and reuse polypropylene since it is a thermoplastic polymer, will soften when reheated, and, thus, may be remolded.", "choice_question": "Is it possible to grind up and reuse polypropylene?", "conversion_reason": "The answer is a clear and concise explanation that can serve as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice scenario by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because polypropylene's semi-crystalline structure allows it to retain mechanical properties after multiple melt cycles", "B": "No, because the polymer chains undergo irreversible scission during the grinding process", "C": "Only if mixed with virgin material, as recycled PP always requires compatibilizers", "D": "Yes, but only for non-structural applications due to severe molecular weight degradation" }, "correct_answer": "A", "explanation": "Correct answer A leverages PP's unique semi-crystalline nature that enables multiple recycling while maintaining properties. Option B exploits confusion between mechanical grinding and chemical degradation. Option C creates a false requirement for virgin material blending. Option D exaggerates the molecular weight loss issue, a common misconception in polymer recycling.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3627, "question": "For NiO with sodium chloride structure, determine the packing factor.", "answer": "0.678.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定NiO的packing factor，答案是一个具体的数值结果（0.678），这表明解答过程涉及计算步骤。 | 知识层次: 题目要求计算NiO的堆积因子，这需要应用基本的晶体结构知识（如NaCl结构）和堆积因子的计算公式。虽然需要理解相关概念，但计算过程相对直接，属于基本公式应用和简单计算的范畴。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算NiO的堆积因子，只需直接应用已知的NaCl结构堆积因子公式（0.678）即可得出答案，无需额外推导或组合多个公式。解题步骤简单，仅需基本概念记忆和简单数值匹配。", "convertible": true, "correct_option": "0.678", "choice_question": "For NiO with sodium chloride structure, the packing factor is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.678", "B": "0.785", "C": "0.740", "D": "0.524" }, "correct_answer": "A", "explanation": "The correct packing factor for NiO with NaCl structure is 0.678, calculated considering the ionic radii of Ni2+ and O2- and the unit cell geometry. Option B (0.785) mimics the packing factor for simple cubic structures, exploiting common confusion between cubic packing types. Option C (0.740) represents FCC/HCP packing factors, a tempting guess for those misapplying close-packing concepts. Option D (0.524) is the simple cubic packing factor, designed to catch those confusing NiO's structure with primitive cubic arrangements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1481, "question": "Qualitatively compare the elastic modulus of ceramic materials, metal materials, and polymer materials", "answer": "Among the three types of materials, ceramic materials have the highest elastic modulus, metal materials have the next highest elastic modulus, and polymer materials have the lowest elastic modulus.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对三种材料的弹性模量进行定性比较，答案需要文字解释和论述，而非选择、判断或计算。 | 知识层次: 题目考查对不同材料弹性模量的基本概念记忆和简单比较，属于基础概念的记忆和理解层次，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于基础概念记忆的范畴，仅需回忆和比较三种材料的基本弹性模量顺序，无需深入分析或复杂推理。正确选项直接给出了明确的比较结果，符合等级1的基本定义简答要求。", "convertible": true, "correct_option": "Among the three types of materials, ceramic materials have the highest elastic modulus, metal materials have the next highest elastic modulus, and polymer materials have the lowest elastic modulus.", "choice_question": "Which of the following correctly compares the elastic modulus of ceramic materials, metal materials, and polymer materials?", "conversion_reason": "The original short answer question asks for a qualitative comparison of the elastic modulus of three types of materials, and the answer is a standard, factual statement. This can be converted into a multiple-choice question by presenting the answer as one of the options and rephrasing the question to fit the multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ceramics > Metals > Polymers (all crystalline forms)", "B": "Metals > Ceramics > Polymers (all amorphous forms)", "C": "Metals > Ceramics ≈ Polymers (all at 500°C)", "D": "Ceramics ≈ Metals > Polymers (all single crystals)" }, "correct_answer": "A", "explanation": "The correct answer is A because crystalline ceramics generally have the highest elastic modulus due to their strong ionic/covalent bonds, followed by metals with metallic bonds, then polymers with weak van der Waals forces. Option B reverses ceramics and metals for amorphous forms, exploiting the misconception that amorphous metals would outperform ceramics. Option C introduces temperature effects (500°C) where polymers would degrade and metals soften, creating a false equivalence. Option D uses single crystal condition to suggest ceramic-metal equivalence, ignoring that even single crystal ceramics maintain higher stiffness than metals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4514, "question": "Name the following polymer(s) that would be suitable for the fabrication of cups to contain hot coffee: polyethylene, polypropylene, poly(vinyl chloride), PET polyester, and polycarbonate. Why?", "answer": "This question asks us to name which, of several polymers, would be suitable for the fabrication of cups to contain hot coffee. At its glass transition temperature, an amorphous polymer begins to soften. The maximum temperature of hot coffee is probably slightly below 100^{\\circ} C\\left(212^{\\circ} F\\right). Of the polymers listed, only polystyrene and polycarbonate have glass transition temperatures of 100^{\\circ} C or above, and would be suitable for this application.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释哪些聚合物适合制作热咖啡杯，并说明原因。答案提供了详细的解释和论述，而不是简单的选择或判断。 | 知识层次: 题目要求学生在理解聚合物玻璃化转变温度的基础上，分析不同聚合物在特定温度条件下的适用性，涉及多个概念的关联和综合分析。虽然不需要复杂的计算或深度推理，但需要对材料性能和应用场景有一定的理解和判断能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生不仅知道各种聚合物的基本性质，还需要了解玻璃化转变温度的概念，并能将其与实际应用场景（热咖啡的温度）联系起来进行综合分析。虽然题目提供了多个选项，但正确解答需要考生排除不合适的选项并选择最合适的聚合物，这涉及多步推理和概念关联。", "convertible": true, "correct_option": "polycarbonate", "choice_question": "Which of the following polymers would be suitable for the fabrication of cups to contain hot coffee?", "conversion_reason": "The original question asks for a specific polymer suitable for a particular application, and the answer provided is a standard term (polycarbonate). This makes it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polycarbonate (Tg ~150°C, high optical clarity)", "B": "PET polyester (Tg ~70°C, excellent barrier properties)", "C": "Polypropylene (Tg ~-10°C, low cost food-grade availability)", "D": "Crosslinked polyethylene (Tg ~-25°C, superior chemical resistance)" }, "correct_answer": "A", "explanation": "Polycarbonate is correct due to its high glass transition temperature (Tg) maintaining structural integrity at coffee temperatures (~95°C) and optical clarity. PET (B) is misleading as its Tg is dangerously close to coffee temperature despite good barrier properties. Polypropylene (C) exploits food-grade availability bias but its low Tg causes deformation. Crosslinked PE (D) uses chemical resistance as distraction while ignoring critical thermal limitations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2633, "question": "The density of Al2O3 is 3.8g/cm3, calculate how many atoms are contained in 1g?", "answer": "The relative molecular mass of Al2O3 M=26.98×2+16×3=101.96, the number of atoms contained in 1g is 1/101.96×6.023×1023×5=2.95×1022", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算1g Al2O3中的原子数量），答案给出了具体的计算过程和数值结果，符合计算题的特征。 | 知识层次: 题目涉及基本的分子量计算和摩尔概念的应用，属于直接套用公式和简单计算的范畴，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用相对分子质量和阿伏伽德罗常数的概念，但解题步骤较为直接，仅需套用基本公式并进行简单计算即可得出答案。不需要复杂的逻辑推理或多步骤转换，因此在选择题型内属于中等偏下难度。", "convertible": true, "correct_option": "2.95×10^22", "choice_question": "The density of Al2O3 is 3.8g/cm3. How many atoms are contained in 1g of Al2O3?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.95×10^22", "B": "1.18×10^22", "C": "5.90×10^22", "D": "3.54×10^22" }, "correct_answer": "A", "explanation": "The correct answer is A (2.95×10^22) because it properly accounts for both Al and O atoms in the molecular formula Al2O3. Option B (1.18×10^22) is a common error where only the aluminum atoms are counted. Option C (5.90×10^22) results from incorrectly doubling the correct value. Option D (3.54×10^22) comes from miscalculating Avogadro's number application. These distractors exploit common calculation mistakes in stoichiometry and unit conversions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4465, "question": "Glass pieces may also be strengthened by chemical tempering. With this procedure, the glass surface is put in a state of compression by exchanging some of the cations near the surface with other cations having a larger diameter. Suggest one type of cation that, by replacing \\mathrm{Na}^{+}, will induce chemical tempering in a soda-lime glass.", "answer": "Chemical tempering will be accomplished by substitution, for \\mathrm{Na}^{+}, another monovalent cation with a slightly larger diameter. Both K^{+}and \\mathrm{Cs}^{+}fill these criteria, having ionic radii of 0.138 and 0.170 nm, respectively, which are larger than the ionic radius of \\mathrm{Na}^{+}(0.102nm). In fact, soda-lime glasses are tempered by a K^{+}-\\mathrm{Na}^{+}ion exchange.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，需要提出一种可以替代Na+的阳离子，并解释其如何通过化学强化来增强玻璃。答案提供了详细的解释和论述，符合简答题的特征。 | 知识层次: 题目要求考生理解化学强化玻璃的基本原理，并应用离子半径的知识选择合适的阳离子进行替换。这涉及到对离子交换过程的理解和离子半径的比较，属于中等应用层次。虽然题目没有涉及复杂的计算或多步骤分析，但需要考生将多个概念关联起来进行综合分析。 | 难度: 在选择题中属于中等难度，需要理解化学强化玻璃的基本原理，并能够比较不同阳离子的半径大小及其对玻璃性能的影响。虽然题目给出了具体的离子半径数据，但考生仍需具备一定的材料科学基础知识，才能正确选择替换Na⁺的合适阳离子。此外，题目还涉及实际应用中的离子交换过程，需要考生将理论知识与实际应用相结合。", "convertible": true, "correct_option": "K^{+}", "choice_question": "Which of the following cations, by replacing \\mathrm{Na}^{+}, will induce chemical tempering in a soda-lime glass?", "conversion_reason": "The answer is a standard term (K^{+}) that can be presented as a choice among other possible cations. The question can be rephrased to fit a multiple-choice format by asking for the specific cation that meets the criteria.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "K⁺ (ionic radius 138 pm)", "B": "Li⁺ (ionic radius 76 pm)", "C": "Ca²⁺ (ionic radius 100 pm)", "D": "Al³⁺ (ionic radius 53 pm)" }, "correct_answer": "A", "explanation": "Chemical tempering requires substituting Na⁺ (102 pm) with a larger cation to create compressive surface stresses. K⁺ (138 pm) is the only option significantly larger than Na⁺. Li⁺ is smaller and would cause opposite effect. While Ca²⁺ and Al³⁺ are common glass modifiers, their charge difference prevents effective ion exchange with Na⁺. The trap is that AI might consider multivalent ions due to their common presence in glasses, overlooking the charge compatibility requirement for ion exchange.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1001, "question": "Assuming that the active slip system in a face-centered cubic crystal is (111)[011], if the slip dislocation is a pure screw dislocation, what is the direction of the dislocation line?", "answer": "The dislocation line of a pure screw dislocation is parallel to $\\\\vec{b}$, which is [011]", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释和论述来确定位错线的方向，答案提供了详细的解释和方向说明，符合简答题的特征。 | 知识层次: 题目考查对纯螺型位错线方向与伯氏矢量关系的基本概念记忆和理解，属于材料科学中位错理论的基础知识点，不需要复杂的计算或综合分析。 | 难度: 在选择题型中，该题目仅需记忆纯螺型位错线的方向与伯氏矢量平行的基本原理，属于基础概念记忆的简单题目。无需复杂分析或推理步骤，仅需直接回忆定义即可选择正确答案。", "convertible": true, "correct_option": "[011]", "choice_question": "Assuming that the active slip system in a face-centered cubic crystal is (111)[011], if the slip dislocation is a pure screw dislocation, what is the direction of the dislocation line?", "conversion_reason": "The answer is a standard crystallographic direction [011], which can be presented as a clear option among other possible directions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[011]", "B": "[111]", "C": "[101]", "D": "[110]" }, "correct_answer": "A", "explanation": "对于纯螺型位错，位错线方向必须与滑移方向平行。在(111)[011]滑移系中，滑移方向是[011]，因此位错线方向也是[011]。选项B[111]是滑移面法线方向，容易误选。选项C[101]和D[110]都是滑移面上的其他方向，容易因对纯螺型位错理解不深而误选。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4099, "question": "[a] Composites are single-phase materials by definition.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（答案为F表示错误），符合判断题的特征 | 知识层次: 题目考查复合材料定义的基础概念记忆，属于对材料科学基本分类的理解 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆复合材料的定义即可判断正误。题目直接考察对\"复合材料是否为单相材料\"这一基础定义的记忆，无需理解或分析复杂概念，因此属于最低难度等级。", "convertible": true, "correct_option": "F", "choice_question": "[a] Composites are single-phase materials by definition.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect ionic bonding without any covalent character.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics have predominantly ionic bonding, most exhibit some degree of covalent character. The statement uses absolute terms ('all', 'perfect') which are incorrect. Materials like silicon carbide (SiC) and boron nitride (BN) are ceramics with primarily covalent bonding. Even in typically ionic ceramics like MgO, there's measurable covalent contribution to bonding.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2632, "question": "What does the long-range structure (secondary structure) of polymer chain structures include?", "answer": "Relative molecular mass and its distribution, chain flexibility and conformation", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释聚合物链结构的远程结构（二级结构）包括哪些内容，答案需要文字解释和论述，而不是从选项中选择或简单的对错判断。 | 知识层次: 题目考查聚合物长程结构（二级结构）的基本概念，包括相对分子质量及其分布、链柔性和构象等基础知识的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆，但需要考生同时掌握聚合物长程结构的两个关键方面（相对分子质量及其分布、链柔性和构象），并理解它们之间的关联性。这比单纯记忆单一概念（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Relative molecular mass and its distribution, chain flexibility and conformation", "choice_question": "What does the long-range structure (secondary structure) of polymer chain structures include?", "conversion_reason": "The answer is a standard term or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Relative molecular mass and its distribution, chain flexibility and conformation", "B": "Crystallinity degree and spherulite size", "C": "Tacticity and head-to-head configuration", "D": "Glass transition temperature and melting point" }, "correct_answer": "A", "explanation": "The correct answer is A because the long-range (secondary) structure of polymers specifically refers to molecular-level characteristics that affect chain behavior over large distances. Option B describes morphological features (tertiary structure), Option C describes short-range (primary) structural arrangements, and Option D lists bulk material properties - all are common misclassifications due to their close association with polymer characterization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3653, "question": "A niobium alloy is produced by introducing tungsten substitutional atoms in the BCC structure; eventually an alloy is produced that has a lattice parameter of 0.32554nm and a density of 11.95g / {cm}^{3}. Calculate the fraction of the atoms in the alloy that are tungsten.", "answer": "0.345", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解钨原子在合金中的比例，答案是一个具体的数值（0.345），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括晶格参数和密度的关系计算，以及原子分数的推导。这需要理解BCC结构、原子质量和密度之间的关系，并进行综合分析。虽然不涉及复杂的推理或机理解释，但需要多个步骤和概念的综合应用。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC结构、晶格参数与密度的关系，并进行多步计算。题目涉及原子分数计算，需要综合运用材料科学和数学知识，但选项提供了明确目标，减少了开放性问题带来的复杂度。", "convertible": true, "correct_option": "0.345", "choice_question": "A niobium alloy is produced by introducing tungsten substitutional atoms in the BCC structure; eventually an alloy is produced that has a lattice parameter of 0.32554nm and a density of 11.95g/cm³. The fraction of the atoms in the alloy that are tungsten is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be presented among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.345", "B": "0.265", "C": "0.412", "D": "0.298" }, "correct_answer": "A", "explanation": "The correct answer is A (0.345) because it requires precise calculation of atomic fraction considering the BCC structure, lattice parameter, and density. Option B (0.265) is a common error from misapplying the atomic packing factor. Option C (0.412) exploits the tendency to overestimate tungsten's contribution due to its higher atomic weight. Option D (0.298) is designed to trap those who incorrectly assume linear density variation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3022, "question": "Comparison of mechanical properties, the (1) of polymers is better than that of metal materials. A. Stiffness B. Strength C. Impact strength (toughness) D. Specific strength", "answer": "(1)D", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对聚合物和金属材料机械性能基本概念的对比记忆，属于基础概念的记忆和理解。 | 难度: 该题目属于基础概念记忆层次，但需要考生理解\"specific strength\"的定义（强度与密度之比）并能与金属材料进行简单比较。虽然不涉及复杂分析，但比单纯记忆定义略高一个难度层次，属于概念理解和简单辨析级别。", "convertible": true, "correct_option": "D", "choice_question": "Comparison of mechanical properties, the (1) of polymers is better than that of metal materials.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Stiffness", "B": "Strength", "C": "Impact strength (toughness)", "D": "Specific strength" }, "correct_answer": "D", "explanation": "Specific strength (strength-to-weight ratio) is the correct answer because polymers often have better specific strength than metals due to their lower density. Option A (Stiffness) is a cognitive bias trap as polymers generally have lower elastic modulus than metals. Option B (Strength) exploits the common misconception that metals always have higher absolute strength. Option C (Impact strength) is a professional intuition trap since some polymers do exhibit good toughness, but this is not universally better than metals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4658, "question": "Magnesium (Mg) has an HCP crystal structure and a density of 1.74 g/cm3. What is the volume of its unit cell in cubic centimeters?", "answer": "the volume of the unit cell is 1.39 × 10^-22 cm3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解镁的HCP晶胞体积，答案是一个具体的数值结果。 | 知识层次: 题目需要应用基本公式（密度公式）进行简单计算，涉及HCP晶体结构的基本参数，但不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用密度公式和HCP晶体结构的基本参数进行计算，属于单一公式直接计算的类型。解题步骤简单，仅需套用公式并代入已知数值，无需复杂的分析或组合多个公式。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "1.39 × 10^-22 cm3", "choice_question": "Magnesium (Mg) has an HCP crystal structure and a density of 1.74 g/cm3. What is the volume of its unit cell in cubic centimeters?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.39 × 10^-22 cm3", "B": "2.78 × 10^-22 cm3", "C": "4.16 × 10^-22 cm3", "D": "5.55 × 10^-22 cm3" }, "correct_answer": "A", "explanation": "The correct answer is A because for HCP structure with 6 atoms per unit cell, using Mg's atomic weight (24.305 g/mol) and Avogadro's number, the calculation yields 1.39 × 10^-22 cm3. Option B is 2x the correct value, exploiting the common mistake of miscounting HCP atoms as 12 instead of 6. Option C is 3x the correct value, targeting those who confuse HCP with BCC packing. Option D is 4x the correct value, preying on the tendency to overcomplicate density calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1426, "question": "What is the intrinsic magnetic moment of a substance?", "answer": "The intrinsic magnetic moment of a substance refers to the sum of all atomic magnetic moments in the absence of an external magnetic field.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"intrinsic magnetic moment\"进行文字解释和论述，答案是一个定义性的陈述，不需要计算或选择，符合简答题的特征。 | 知识层次: 题目考查对\"本征磁矩\"这一基本概念的定义和记忆，属于基础概念的理解层面，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目仅要求记忆和识别“内在磁矩”的基本定义，属于最基础的概念记忆层次。正确选项直接给出了定义，无需进行任何解释或分析，解题步骤极为简单，符合等级1“基本定义简答”的标准。", "convertible": true, "correct_option": "The intrinsic magnetic moment of a substance refers to the sum of all atomic magnetic moments in the absence of an external magnetic field.", "choice_question": "What is the intrinsic magnetic moment of a substance?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The sum of all atomic magnetic moments in the absence of an external magnetic field", "B": "The maximum magnetization achievable when all atomic dipoles are perfectly aligned", "C": "The magnetic moment per unit volume under saturation conditions", "D": "The residual magnetic moment after removing an applied field (remanence)" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines the intrinsic magnetic moment as the inherent atomic-level magnetism without external influence. Option B describes saturation magnetization, a common confusion point. Option C mixes the concept with volumetric density under specific conditions. Option D substitutes remanence, which is a post-application residual effect rather than intrinsic property. These distractors exploit: 1) confusion between intrinsic and extrinsic magnetic properties (B/D), 2) unit/condition traps (C), and 3) the subtle distinction between spontaneous and induced magnetization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1225, "question": "Metal solidification occurs through two processes: nucleation of the solid phase and grain growth. During the grain growth process, the liquid-solid interface of pure metals (such as Fe, Ni, Cu, Au, etc.) generally remains smooth.", "answer": "~\\\\times~", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（金属凝固过程中纯金属的液固界面通常保持平滑），并要求判断其正确性（答案给出的是×，表示错误）。这符合判断题的特征，即判断陈述的对错。 | 知识层次: 题目考查金属凝固过程中晶粒生长和液固界面形态的基础概念记忆，属于对基本原理的记忆性知识 | 难度: 该题目属于基础概念记忆层次，仅需判断关于金属凝固过程中液固界面形态的基本陈述是否正确。题目涉及的知识点较为简单，属于纯记忆性内容，无需深入理解或分析多个概念。在选择题型中，此类正误判断题通常属于最低难度等级。", "convertible": true, "correct_option": "~\\\\times~", "choice_question": "Metal solidification occurs through two processes: nucleation of the solid phase and grain growth. During the grain growth process, the liquid-solid interface of pure metals (such as Fe, Ni, Cu, Au, etc.) generally remains smooth.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "During the grain growth process in pure metals, the liquid-solid interface remains smooth under all solidification conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While pure metals often exhibit smooth liquid-solid interfaces during solidification, this is not universally true under all conditions. Interface morphology depends on factors like cooling rate and thermal gradients. Rapid solidification or certain thermal conditions can lead to unstable, dendritic growth patterns even in pure metals. The absolute term 'all conditions' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2863, "question": "Given that the yield strength of industrial pure copper is ${\\\\pmb{\\\\sigma{s}}}=70~{\\\\bf M}{\\\\bf P}{\\\\bf a}$, its grain size is $N{\\\\mathrm{A}}=18$ per $'\\\\mathbf{m}\\\\mathbf{m}^{2}$, and when $N{\\\\mathbf{A}}=$ $\\\\bf{4025}$ per $\\\\scriptstyle{\\\\prime}{\\\\mathbf{m}\\\\mathbf{m}^{2}}$, ${\\\\pmb{\\\\sigma}}{\\\\mathsf{S}}={\\\\pmb{95}}\\\\mathbf{M}\\\\mathbf{P}{\\\\bf a}$. Calculate ${\\\\pmb\\\\sigma_{\\\\mathfrak{s}}}$ when $N{\\\\mathbf{A}}=260$ per $\\\\scriptstyle{\\\\left/{\\\\mathfrak{m m}}^{2}\\\\right.}$.", "answer": "Let the average grain diameter be $^{d}$, and the number of grains per $\\\\scriptstyle\\\\mathtt{m m}^{2}$ be $N_{\\\\Lambda}$. It can be proven that: Thus $$d=\\\\sqrt{\\\\frac{8}{3\\\\pi N_{\\\\Lambda}}}$$$$d_{1}=\\\\sqrt{\\\\frac{8}{3\\\\pi\\\\times\\\\mathrm{i}8}}=0.217(\\\\mathrm{mm})$$$$d_{2}=\\\\sqrt{\\\\frac{8}{3\\\\pi\\\\times4025}}=1.452\\\\times10^{-2}(\\\\mathrm{mm})$$$$d_{3}=\\\\sqrt{\\\\frac{8}{3\\\\pi\\\\times260}}=5.714\\\\times10^{-2}(\\\\mathrm{mm})$$Substituting into the Hall-Petch formula: Solving $$\\\\left\\\\{\\\\begin{array}{l l}{{70=\\\\sigma_{0}+k(0,217\\\\times10^{-3})^{-\\\\frac{1}{2}}}}\\\\ {{95=\\\\sigma_{0}+k(1,452\\\\times10^{-5})^{-\\\\frac{1}{2}}}}\\\\end{array}\\\\right.$$$$\\\\begin{array}{r}{\\\\sigma_{0}=61,3\\\\mathrm{MPa},\\\\quad k=0,1285}\\\\end{array}$$$$\\\\sigma_{5}=61,3+0.1285\\\\times(5,714\\\\times10^{-5})^{-\\\\frac{1}{2}}=78.3(\\\\mathrm{MPa})$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（Hall-Petch公式）来求解特定条件下的屈服强度，答案给出了详细的计算过程和最终数值结果。 | 知识层次: 题目需要应用Hall-Petch公式进行多步计算，涉及不同晶粒尺寸下的屈服强度求解，需要理解公式中各参数的含义并进行适当的代数运算。虽然不涉及复杂的机理分析或创新设计，但计算过程较为复杂，需要一定的综合分析能力。 | 难度: 在选择题中属于中等偏上难度，题目涉及多步骤计算和概念关联。需要掌握Hall-Petch公式的应用，能够正确计算晶粒尺寸，并建立方程组求解材料常数。虽然题目提供了正确选项，但解题过程需要综合运用材料科学知识和数学计算能力，属于综合性计算问题。", "convertible": true, "correct_option": "78.3 MPa", "choice_question": "Given that the yield strength of industrial pure copper is ${\\pmb{\\sigma{s}}}=70~{\\bf M}{\\bf P}{\\bf a}$, its grain size is $N{\\mathrm{A}}=18$ per $'\\mathbf{m}\\mathbf{m}^{2}$, and when $N{\\mathbf{A}}=$ $\\bf{4025}$ per $\\scriptstyle{\\prime}{\\mathbf{m}\\mathbf{m}^{2}}$, ${\\pmb{\\sigma}}{\\mathsf{S}}={\\pmb{95}}\\mathbf{M}\\mathbf{P}{\\bf a}$. Calculate ${\\pmb\\sigma_{\\mathfrak{s}}}$ when $N{\\mathbf{A}}=260$ per $\\scriptstyle{\\left/{\\mathfrak{m m}}^{2}\\right.}$.", "conversion_reason": "The calculation problem has a definite numerical answer (78.3 MPa), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "78.3 MPa", "B": "72.1 MPa", "C": "85.6 MPa", "D": "68.9 MPa" }, "correct_answer": "A", "explanation": "正确答案A是通过Hall-Petch公式精确计算得出的结果。干扰项B利用了常见的线性外推错误，忽略了晶界强化的非线性特性。干扰项C故意混淆了不同晶粒尺寸区间的强化机制，适用于纳米晶而非本题的微米级晶粒。干扰项D则错误地使用了反向比例关系，这是初学者常见的直觉错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2936, "question": "When a deformed material is reheated and undergoes recovery and recrystallization phenomena, the significant decrease in point defect concentration occurs during (A) recovery stage (B) recrystallization stage (C) grain growth stage", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项(A)、(B)、(C)中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查对材料科学中恢复和再结晶过程中点缺陷浓度变化的基础概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 在选择题中属于中等偏易难度，需要理解恢复阶段和再结晶阶段的基本概念，并能区分点缺陷浓度显著下降发生的具体阶段。虽然涉及多个概念，但选项间的区分度较高，只需基础概念理解和简单辨析即可正确作答。", "convertible": true, "correct_option": "A", "choice_question": "When a deformed material is reheated and undergoes recovery and recrystallization phenomena, the significant decrease in point defect concentration occurs during", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The annihilation of dislocations during polygonization", "B": "The nucleation of new strain-free grains", "C": "The migration of high-angle grain boundaries", "D": "The thermal activation of vacancy diffusion" }, "correct_answer": "A", "explanation": "The significant decrease in point defect concentration occurs during the recovery stage (A) due to dislocation annihilation and polygonization. Option B is a strong distractor as recrystallization involves new grain formation, but point defect reduction primarily happens earlier. Option C exploits the common confusion between recovery and grain growth mechanisms. Option D uses a technically correct but irrelevant process that occurs throughout heating.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4394, "question": "Compare white and nodular cast irons with respect to mechanical characteristics.", "answer": "White iron--Extremely hard and brittle. Nodular cast iron--Moderate strength and ductility.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较两种铸铁的机械特性，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对白口铸铁和球墨铸铁机械性能的基本概念记忆和理解，属于基础概念对比，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两种铸铁材料的机械特性比较，但正确选项直接给出了明确的对比描述（白铸铁的硬脆性和球墨铸铁的中等强度与延展性），不需要复杂的推理或概念整合。这属于基础概念记忆层次，但需要考生能够区分和记忆两种材料的特性，属于概念解释和描述级别。", "convertible": true, "correct_option": "White iron--Extremely hard and brittle. Nodular cast iron--Moderate strength and ductility.", "choice_question": "Which of the following correctly compares white and nodular cast irons with respect to mechanical characteristics?", "conversion_reason": "The answer is a standard comparison that can be presented as a correct option among other plausible but incorrect comparisons.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "White iron--Extremely hard and brittle. Nodular cast iron--Moderate strength and ductility", "B": "White iron--High toughness and impact resistance. Nodular cast iron--Low thermal conductivity", "C": "White iron--Excellent machinability. Nodular cast iron--High hardness and wear resistance", "D": "White iron--High ductility and fracture toughness. Nodular cast iron--Low elastic modulus" }, "correct_answer": "A", "explanation": "Correct answer A accurately describes white iron's characteristic hardness/brittleness due to cementite formation, and nodular iron's balanced properties from graphite spheroids. Option B reverses white iron's actual brittleness with toughness. Option C falsely attributes machinability to white iron (known for being difficult to machine) and misrepresents nodular iron's primary advantage. Option D incorrectly assigns ductility to white iron and misleads by suggesting nodular iron has unusually low elastic modulus.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2817, "question": "What are the changes in properties of a Gu–30%Zn brass sheet after cold rolling?", "answer": "After cold rolling, the strength and hardness of the brass sheet increase, while plasticity and toughness decrease, which is the phenomenon of work hardening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释冷轧后黄铜板材性能的变化，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释冷轧后黄铜板材性能的变化，涉及多个性能指标（强度、硬度、塑性、韧性）的综合分析，需要理解冷加工对材料性能的影响机制（加工硬化现象），属于中等应用层次的知识。 | 难度: 在选择题中属于中等难度，需要理解冷轧对黄铜板材性能的影响，包括强度、硬度、塑性和韧性的变化，并关联到加工硬化现象。虽然不需要多步计算，但需要对材料科学中的基本概念有较好的掌握，并能综合分析不同性能指标的变化趋势。", "convertible": true, "correct_option": "After cold rolling, the strength and hardness of the brass sheet increase, while plasticity and toughness decrease, which is the phenomenon of work hardening.", "choice_question": "What are the changes in properties of a Gu–30%Zn brass sheet after cold rolling?", "conversion_reason": "The answer is a standard description of the phenomenon of work hardening, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yield strength increases but ultimate tensile strength remains unchanged", "B": "Both hardness and electrical conductivity increase significantly", "C": "Ductility improves while maintaining original yield strength", "D": "Recrystallization temperature decreases due to stored energy accumulation" }, "correct_answer": "A", "explanation": "The correct answer is A because cold rolling introduces dislocations that increase yield strength through work hardening, while ultimate tensile strength is less affected in this alloy system. Option B is a cognitive bias trap - while hardness increases, conductivity should decrease due to dislocation scattering. Option C reverses the expected ductility behavior and violates the Hall-Petch relationship. Option D is a professional intuition trap - while stored energy increases, recrystallization temperature actually increases for brass due to its specific stacking fault energy characteristics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 447, "question": "What is the equivalent time required to achieve the same carburization depth at 1000°C (1273K) as 10 hours at 900°C (1173K), given Q=32900 cal/mol and R=1.987 cal?", "answer": "t_1273 = D_1173 * t_1173 / D_1273 = 10 * exp[-32900/(1.987*1173)] / exp[-32900/(1.987*1273)] = 10 * exp(-14.1156) / exp(-13.0068) h = 10 * exp(-1.5089) h = 10 * 0.3299 h = 3.299 h", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解等效时间，涉及指数函数和温度转换的计算过程。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括公式应用、指数运算和单位转换，涉及扩散方程的深入理解和温度对扩散系数的影响。虽然不涉及复杂的推理或创新设计，但需要综合运用多个知识点进行计算和分析。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程和温度对扩散系数的影响，并进行多步计算（包括指数运算和除法）。虽然题目提供了公式和参数，但解题过程涉及多个概念的综合应用和较复杂的计算步骤，属于综合性计算问题。", "convertible": true, "correct_option": "3.299 h", "choice_question": "What is the equivalent time required to achieve the same carburization depth at 1000°C (1273K) as 10 hours at 900°C (1173K), given Q=32900 cal/mol and R=1.987 cal?", "conversion_reason": "The calculation problem has a definite numerical answer, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.299 h", "B": "1.832 h", "C": "5.647 h", "D": "7.214 h" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Arrhenius equation to compare diffusion rates at different temperatures. Option B is designed to trap those who incorrectly linearize the temperature difference. Option C exploits a common error in unit conversion between Celsius and Kelvin. Option D is derived from a flawed assumption that the time difference should be proportional to the absolute temperature ratio.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1239, "question": "When an embryo appears in an undercooled liquid, what can the total free energy change ΔG be written as?", "answer": "ΔG=VΔGV+σS", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求写出总自由能变化的表达式，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目考查的是对过冷液体中胚胎出现时总自由能变化公式的记忆和理解，属于基础概念的记忆性知识，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即自由能变化的基本表达式。正确选项直接给出了公式形式，无需解释或推导，属于最基础的定义简答级别。题目仅要求考生识别并选择正确的公式表达，不涉及任何分析或复杂推理过程。", "convertible": true, "correct_option": "ΔG=VΔGV+σS", "choice_question": "When an embryo appears in an undercooled liquid, what can the total free energy change ΔG be written as?", "conversion_reason": "The answer is a standard formula, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ΔG=VΔGV+σS", "B": "ΔG=ΔH-TΔS", "C": "ΔG=4/3πr³ΔGV+4πr²σ", "D": "ΔG=ΔGV+σ" }, "correct_answer": "A", "explanation": "The correct answer A represents the total free energy change as the sum of volume free energy (VΔGV) and surface energy (σS). Option B is a common thermodynamic equation but does not account for the embryo formation specifics. Option C is a spherical approximation that would be correct only for spherical embryos, making it a context-specific trap. Option D omits the critical volume and area terms, representing a dimensional inconsistency trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1198, "question": "What kind of motion can an edge dislocation undergo?", "answer": "Slip", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释边缘位错可以进行的运动类型，答案需要文字描述（\"Slip\"），属于需要简要文字解释的简答题类型。 | 知识层次: 题目考查位错运动类型的基础概念记忆，仅需回答\"滑移\"这一基本定义，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对基本定义（edge dislocation的运动方式）的记忆，属于最基础的概念性知识，无需复杂分析或推理步骤。正确选项\"Slip\"是位错运动的标准术语，直接对应教材中的基础定义，符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "Slip", "choice_question": "What kind of motion can an edge dislocation undergo?", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip", "B": "Climb", "C": "Twinning", "D": "Diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A (Slip) because edge dislocations primarily move through slip along the slip plane under shear stress. Option B (Climb) is a plausible but incorrect answer as it requires vacancy diffusion and is not the primary motion mode. Option C (Twinning) exploits the cognitive bias of associating dislocation motion with crystal deformation mechanisms. Option D (Diffusion) is a professional intuition trap, as diffusion is related but not the direct motion mechanism for edge dislocations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 366, "question": "During the deformation of polycrystals, under a certain amount of deformation, why do some grains exhibit single slip while others exhibit multiple slips?", "answer": "Hard-oriented stress axes induce multiple slips, such as <111>, <100>, <110> directions, while soft-oriented stress axes correspond to single slip, such as the <123> direction.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么在变形过程中某些晶粒表现出单滑移而其他晶粒表现出多滑移，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释多晶变形过程中不同晶粒表现出单滑移和多滑移的原因，涉及晶体取向、应力轴方向与滑移系激活的复杂关系。需要综合运用晶体塑性变形理论、Schmid因子分析以及不同晶向的滑移系激活条件，属于机理分析和推理解释的范畴。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Hard-oriented stress axes induce multiple slips, such as <111>, <100>, <110> directions, while soft-oriented stress axes correspond to single slip, such as the <123> direction.", "choice_question": "During the deformation of polycrystals, under a certain amount of deformation, why do some grains exhibit single slip while others exhibit multiple slips?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hard-oriented stress axes induce multiple slips, such as <111>, <100>, <110> directions, while soft-oriented stress axes correspond to single slip, such as the <123> direction.", "B": "Grain boundary diffusion dominates in hard-oriented grains, leading to multiple slips, while volume diffusion controls soft-oriented grains resulting in single slip.", "C": "Grains with higher elastic modulus exhibit multiple slips due to increased dislocation density, while those with lower modulus show single slip.", "D": "The critical resolved shear stress is lower for multiple slip systems, causing hard-oriented grains to activate more slip systems simultaneously." }, "correct_answer": "A", "explanation": "The correct answer A explains the fundamental crystallographic orientation effect on slip systems activation. Option B incorrectly applies diffusion mechanisms to slip phenomena. Option C misattributes the effect to elastic modulus rather than crystallographic orientation. Option D reverses the relationship between CRSS and slip system activation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 542, "question": "Peritectic transformation", "answer": "Peritectic transformation: At a certain temperature, a liquid phase with a specific composition interacts with a solid phase of a specific composition to form a new solid phase with another specific composition.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Peritectic transformation\"进行文字解释和论述，答案提供了详细的定义和过程描述，符合简答题的特征 | 知识层次: 题目考查对包晶转变（Peritectic transformation）这一基本概念的定义和描述，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆，但需要考生准确理解并描述包晶转变的定义和过程，涉及液相与固相在特定条件下的相互作用以及新固相的形成。这比单纯记忆基本定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Peritectic transformation: At a certain temperature, a liquid phase with a specific composition interacts with a solid phase of a specific composition to form a new solid phase with another specific composition.", "choice_question": "下列关于Peritectic transformation的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Peritectic transformation involves a liquid phase reacting with a solid phase to form a new solid phase at a specific temperature", "B": "Peritectic transformation is a diffusionless transformation similar to martensitic transformation", "C": "Peritectic transformation occurs when two solid phases combine to form a single solid phase", "D": "Peritectic transformation is characterized by complete solubility of components in both liquid and solid phases" }, "correct_answer": "A", "explanation": { "correct": "Option A is correct because peritectic transformation specifically involves a liquid phase reacting with a solid phase to form a new solid phase at a fixed temperature, which is the textbook definition.", "distractors": { "B": "This exploits the common confusion between diffusion-based and diffusionless transformations. While martensitic is diffusionless, peritectic involves diffusion.", "C": "This describes a solid-state reaction, not a peritectic transformation which must involve a liquid phase.", "D": "This incorrectly applies characteristics of isomorphous systems to peritectic systems, exploiting confusion between different phase diagram types." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3962, "question": "A cylindrical specimen of a metal alloy 48.8mm long and 9.09mm in diameter is stressed in tension. A true stress of 327 MPa causes the specimen to plastically elongate to a length of 55 mm. If it is known that the strain-hardening exponent for this alloy is 0.3 , calculate the true stress (in MPa )necessary to plastically elongate a specimen of this same material from a length of 48.8mm to a length of 57.6 mm.", "answer": "390 MPa", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（应变硬化指数公式）来求解真实应力，最终需要给出具体的数值计算结果（390 MPa）。 | 知识层次: 题目需要进行多步计算，包括应变计算、应变硬化公式的应用以及不同条件下的应力转换。虽然涉及的概念（如应变硬化指数）较为基础，但需要将这些概念关联起来进行综合分析，才能得出最终结果。思维过程需要一定的深度和逻辑性，但不需要进行复杂的机理分析或创新应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及塑性变形、应变硬化指数、真实应力-应变关系等概念的综合运用，解题步骤包括计算初始和最终应变、应用应变硬化公式等，属于多步骤计算过程。虽然题目提供了正确选项，但解题过程需要一定的综合分析能力，因此在选择题型内属于等级3难度。", "convertible": true, "correct_option": "390 MPa", "choice_question": "A cylindrical specimen of a metal alloy 48.8mm long and 9.09mm in diameter is stressed in tension. A true stress of 327 MPa causes the specimen to plastically elongate to a length of 55 mm. If it is known that the strain-hardening exponent for this alloy is 0.3, what is the true stress (in MPa) necessary to plastically elongate a specimen of this same material from a length of 48.8mm to a length of 57.6 mm?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "390 MPa", "B": "355 MPa", "C": "412 MPa", "D": "327 MPa" }, "correct_answer": "A", "explanation": "正确答案A通过真实应变计算和Hollomon方程得出。干扰项B忽略了应变硬化指数的非线性影响，是线性外推的错误结果。干扰项C错误地使用了工程应变而非真实应变进行计算。干扰项D直接使用了题目中给出的初始应力值，忽略了不同应变条件下的应力变化。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 66, "question": "Describe the basic types of dislocations and their characteristics.", "answer": "There are two main types of dislocations: edge dislocation and screw dislocation. Characteristics of edge dislocation: the slip direction is perpendicular to the dislocation line, denoted by the symbol ⊥, with an extra half-plane of atoms. Characteristics of screw dislocation: the slip direction is parallel to the dislocation line, the plane perpendicular to the dislocation line is not flat, presenting a spiral shape, hence called screw dislocation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求描述位错的基本类型及其特征，需要文字解释和论述，而不是选择、判断或计算。答案提供了详细的文字描述，符合简答题的特点。 | 知识层次: 题目考查对位错基本类型（刃位错和螺位错）及其特征的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目要求考生描述两种基本位错类型及其特征，属于概念解释和描述的层次。虽然需要记忆和区分两种位错的定义和特点，但不需要进行复杂的分析或比较，因此属于中等难度。", "convertible": true, "correct_option": "There are two main types of dislocations: edge dislocation and screw dislocation. Characteristics of edge dislocation: the slip direction is perpendicular to the dislocation line, denoted by the symbol ⊥, with an extra half-plane of atoms. Characteristics of screw dislocation: the slip direction is parallel to the dislocation line, the plane perpendicular to the dislocation line is not flat, presenting a spiral shape, hence called screw dislocation.", "choice_question": "Which of the following correctly describes the basic types of dislocations and their characteristics?", "conversion_reason": "The answer is a standard description of the types and characteristics of dislocations, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Edge dislocation: slip direction perpendicular to dislocation line (⊥), extra half-plane of atoms. Screw dislocation: slip direction parallel to dislocation line, spiral atomic arrangement around the line.", "B": "Edge dislocation: slip direction parallel to dislocation line, extra quarter-plane of atoms. Screw dislocation: slip direction at 45° to dislocation line, helical atomic arrangement.", "C": "Edge dislocation: Burgers vector parallel to dislocation line, creates tensile strain field. Screw dislocation: Burgers vector perpendicular to dislocation line, creates shear strain field.", "D": "Both types have slip directions at 45° to dislocation lines; edge dislocations create compressive strain while screw dislocations create torsional strain." }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the two fundamental dislocation types with their defining characteristics. Option B introduces a 'quarter-plane' error and incorrect angle for screw dislocation. Option C reverses the Burgers vector relationships and misrepresents strain fields. Option D completely distorts the angular relationships and strain fields, creating a plausible-sounding but fundamentally wrong description. The traps exploit common misconceptions about Burgers vector orientation and strain fields, while using technically accurate terminology in wrong contexts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1207, "question": "When a crystal undergoes tensile slip, the slip plane is driven to rotate, attempting to align parallel to the (16), while the slip direction also rotates to coincide with the (17) direction.", "answer": "(16) direction of the force axis; (17) maximum resolved shear stress", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求填写特定术语或概念来完成句子，答案需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目涉及晶体滑移过程中滑移面和滑移方向的旋转行为，需要理解滑移机制与外力方向及最大分切应力方向的关系。这需要将基础概念（滑移面、滑移方向、分切应力）进行关联分析，属于中等应用层次的知识。 | 难度: 在选择题中属于中等难度，需要理解晶体滑移过程中的力学行为，并关联滑移面和滑移方向的旋转机制。题目涉及对力轴方向和最大分解剪应力方向的概念理解，要求考生能够综合分析滑移系统的响应。虽然不涉及复杂计算，但需要对材料力学行为有较深的理解。", "convertible": true, "correct_option": "direction of the force axis; maximum resolved shear stress", "choice_question": "When a crystal undergoes tensile slip, the slip plane is driven to rotate, attempting to align parallel to the ______, while the slip direction also rotates to coincide with the ______ direction.", "conversion_reason": "The short answer question has specific standard terms as answers, which can be converted into a multiple-choice format by providing options for the blanks.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "direction of the force axis; maximum resolved shear stress", "B": "direction of maximum normal stress; direction of the force axis", "C": "direction of minimum shear stress; direction of maximum normal stress", "D": "direction of maximum shear stress; direction of minimum normal stress" }, "correct_answer": "A", "explanation": "The correct answer is A because during tensile slip, the slip plane rotates to align with the force axis to minimize shear stress, while the slip direction aligns with the maximum resolved shear stress direction to facilitate dislocation motion. Option B is a common misconception where students confuse maximum normal stress with force axis alignment. Option C reverses the actual physical principles by suggesting alignment with minimum shear stress. Option D creates a false symmetry by suggesting alignment with both maximum shear and minimum normal stresses, which doesn't reflect actual crystal rotation mechanics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1982, "question": "At $800^{\\circ}\\mathrm{C}$, one atom in $10^{10}$ atoms has sufficient energy to move within the solid, while at $900^{\\circ}\\mathrm{C}$, only one atom in $10^{9}$ atoms does. Calculate the activation energy (J/atom).", "answer": "$0.4\\times10^{-18}~\\mathrm{J}/$ atom", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解激活能（J/atom），答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用阿伦尼乌斯公式进行多步计算，涉及温度与激活能的关系，需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解阿伦尼乌斯方程的概念，并进行多步计算和综合分析。题目涉及温度变化与活化能的关系，需要考生将给定的数据转换为合适的数学表达式，并进行对数运算来求解活化能。虽然计算步骤较多，但在选择题型中，正确选项的提示可以降低部分难度。", "convertible": true, "correct_option": "$0.4\\times10^{-18}~\\mathrm{J}/$ atom", "choice_question": "At $800^{\\circ}\\mathrm{C}$, one atom in $10^{10}$ atoms has sufficient energy to move within the solid, while at $900^{\\circ}\\mathrm{C}$, only one atom in $10^{9}$ atoms does. The activation energy (J/atom) is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.4×10⁻¹⁸ J/atom", "B": "1.2×10⁻¹⁹ J/atom", "C": "2.5×10⁻¹⁹ eV/atom", "D": "0.8×10⁻¹⁸ J/mol" }, "correct_answer": "A", "explanation": "正确答案A使用阿伦尼乌斯方程计算活化能，考虑了温度对原子迁移概率的影响。干扰项B利用常见错误计算路径产生看似合理的数值。干扰项C故意混用eV和J单位制造陷阱。干扰项D使用正确的数值但错误的单位（J/mol而非J/atom），利用材料科学中常见的单位混淆问题。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2126, "question": "If carburizing is performed for 10 hours at both 927°C and 870°C, what is the difference in carburized layer thickness?", "answer": "δ927τ/δ870τ=1.41.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来比较两种温度下渗碳层厚度的差异，答案以数值比例形式给出，体现了计算题的特征。 | 知识层次: 题目需要应用扩散定律和温度对扩散系数的影响公式进行多步计算，涉及不同温度下扩散系数的比较和计算，需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程的温度依赖关系（阿伦尼乌斯方程），进行多步计算比较不同温度下的扩散系数，并最终推导出厚度比例关系。虽然题目提供了正确选项减少了计算量，但仍需掌握碳扩散的物理机制和数学关系才能正确选择。", "convertible": true, "correct_option": "δ927τ/δ870τ=1.41", "choice_question": "If carburizing is performed for 10 hours at both 927°C and 870°C, what is the ratio of carburized layer thickness (δ927τ/δ870τ)?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.41", "B": "1.73", "C": "2.24", "D": "0.71" }, "correct_answer": "A", "explanation": "The correct answer is A (1.41) because the carburized layer thickness is proportional to the square root of the diffusion coefficient, which follows an Arrhenius relationship. The ratio is calculated using the activation energy for carbon diffusion in iron. Option B (1.73) is a trap for those who mistakenly use a linear temperature ratio. Option C (2.24) exploits confusion with the temperature difference in Kelvin. Option D (0.71) is the inverse of the correct ratio, targeting those who reverse the temperature order.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 916, "question": "Briefly describe the gravity segregation in the macrosegregation of ingots", "answer": "Gravity segregation: During solidification, the solid phase and the liquid phase have different densities, causing deposition or floating, which results in uneven composition between the lower and upper ends of the ingot, also on a macroscopic scale.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述重力偏析在铸锭宏观偏析中的表现，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目考查对重力偏析这一基本概念的记忆和理解，涉及定义和基本原理的解释，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求的是基础概念记忆，但需要考生对重力偏析的定义、形成原因及其在宏观偏析中的表现有一定的理解和描述能力。题目不仅要求记忆，还需要能够简要解释现象背后的原理，因此难度略高于纯粹的定义记忆题。", "convertible": true, "correct_option": "Gravity segregation: During solidification, the solid phase and the liquid phase have different densities, causing deposition or floating, which results in uneven composition between the lower and upper ends of the ingot, also on a macroscopic scale.", "choice_question": "Which of the following best describes gravity segregation in the macrosegregation of ingots?", "conversion_reason": "The answer is a standard description of a concept, which can be converted into a multiple-choice question format by providing the correct description as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Gravity segregation: During solidification, the solid phase and the liquid phase have different densities, causing deposition or floating, which results in uneven composition between the lower and upper ends of the ingot, also on a macroscopic scale.", "B": "Gravity segregation occurs when lighter alloy elements migrate upwards due to thermal convection currents during the cooling process, creating a concentration gradient along the vertical axis.", "C": "Gravity segregation is caused by the preferential nucleation of high-density phases at the bottom of the ingot due to gravitational compression during solidification.", "D": "Gravity segregation results from the difference in solidification rates between the top and bottom of the ingot, where slower cooling at the top allows more time for solute redistribution." }, "correct_answer": "A", "explanation": "The correct answer A precisely describes gravity segregation as density-driven separation during solidification. Option B incorrectly attributes the phenomenon to thermal convection rather than density differences. Option C wrongly suggests gravitational compression affects nucleation. Option D mistakenly associates segregation with cooling rate differences rather than density-driven phase separation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2926, "question": "When a pure metal undergoes an allotropic transformation during cooling from high temperature to room temperature with volume expansion, the atomic coordination number of the low-temperature phase is ___ that of the high-temperature phase. (A) Lower (B) Higher (C) The same", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（A、B、C）中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对同素异构转变过程中原子配位数变化的基础概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（同素异构转变和原子配位数），但需要考生理解体积膨胀与配位数变化之间的关系，并进行简单辨析。题目不涉及复杂概念的区分或深度理解，但比直接记忆性题目（等级1）要求稍高。", "convertible": true, "correct_option": "A", "choice_question": "When a pure metal undergoes an allotropic transformation during cooling from high temperature to room temperature with volume expansion, the atomic coordination number of the low-temperature phase is ___ that of the high-temperature phase.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy for vacancy migration decreases", "B": "The equilibrium vacancy concentration increases", "C": "The dislocation mobility significantly improves", "D": "The stacking fault energy becomes negative" }, "correct_answer": "A", "explanation": "The correct answer is A because applying hydrostatic pressure reduces atomic spacing, which lowers the energy barrier for vacancy migration. Option B is incorrect as pressure decreases vacancy concentration (Le Chatelier's principle), but this counterintuitive relationship challenges AI's tendency to associate 'pressure' with 'increased concentration'. Option C exploits AI's common overgeneralization that pressure always improves mechanical properties, while actually dislocation mobility typically decreases under pressure. Option D uses a physically impossible scenario (negative energy) that may not trigger immediate rejection by AI models trained on diverse materials data.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2172, "question": "Given that the critical resolved shear stress τc for the {111}[110] slip system in pure copper is 1MPa, what stress should be applied in the [001] direction to produce slip in the [101] direction on the (111) plane?", "answer": "For cubic crystals, the angle between two crystallographic directions [u1v1w1] and [u2v2w2] is given by cosφ=(u1u2+v1v2+w1w2)/(√(u1²+v1²+w1²)*√(u2²+v2²+w2²)). Therefore, the angle between the normal direction [111] of the slip plane (111) and the tensile axis [001] is cosφ=(1×0+1×0+1×1)/(√(1²+1²+1²)*√(0²+0²+1²))=1/√3=0.577. The angle between the slip direction [101] and the tensile axis [001] is cosλ=(1×0+0×0+1×1)/(√(1²+0²+1²)*√(0²+0²+1²))=1/√2=0.707. The applied stress σ=τc/(cosφcosλ)=1/(0.577×0.707)=2.45MPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解应力值，解答过程中涉及角度计算和应力公式的应用，最终给出具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括角度计算和应力计算，并需要理解临界分切应力的概念及其与施加应力的关系。虽然涉及公式的直接应用，但需要综合运用晶体学知识和力学概念来解决问题。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体学方向计算、临界分切应力概念，并进行多步骤的向量点积和反余弦计算。虽然题目提供了公式，但需要正确应用并综合计算才能得出最终应力值，涉及中等应用层次的知识关联和综合分析能力。", "convertible": true, "correct_option": "2.45MPa", "choice_question": "Given that the critical resolved shear stress τc for the {111}[110] slip system in pure copper is 1MPa, what stress should be applied in the [001] direction to produce slip in the [101] direction on the (111) plane?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.45MPa", "B": "1.73MPa", "C": "1.00MPa", "D": "3.46MPa" }, "correct_answer": "A", "explanation": "The correct answer requires calculating the Schmid factor for the [001] direction on the (111) plane with [101] slip direction. The Schmid factor is cos(φ)cos(λ) where φ=54.7° (angle between [001] and (111) normal) and λ=45° (angle between [001] and [101]). This gives a Schmid factor of 0.408, requiring 2.45MPa applied stress to reach the critical resolved shear stress of 1MPa. Option B is the critical resolved shear stress multiplied by √3, exploiting confusion with crystal geometry. Option C is the raw critical resolved shear stress value, tempting those who forget to calculate the Schmid factor. Option D is 2 times the correct answer, targeting those who miscalculate the angle relationships.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1471, "question": "The presence of dislocations always increases the free energy of a crystal.", "answer": "Correct", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（Correct/Incorrect），属于典型的判断题形式。答案只需给出对错判断，无需解释或计算。 | 知识层次: 题目考查对位错基本性质的理解，属于晶体缺陷的基础概念记忆范畴 | 难度: 该题目属于基础概念记忆层次，仅需判断关于位错增加晶体自由能量的陈述是否正确。在选择题型中，这类直接考察定义或基本原理记忆的题目属于最低难度等级，无需复杂分析或推理过程。", "convertible": true, "correct_option": "Correct", "choice_question": "The presence of dislocations always increases the free energy of a crystal.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The presence of dislocations always increases the free energy of a crystal.", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "While dislocations can sometimes lower energy in specific contexts (like strain hardening), the absolute statement is correct because dislocations inherently distort the crystal lattice, increasing strain energy. The key is recognizing 'always' applies to the fundamental physics, not special cases where other energy terms may dominate.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 158, "question": "A glass composition (wt%) is Na2O 14%, CaO 13%, SiO2 73%, with a density of 2.5 g/cm3. If soda ash, limestone, and quartz sand are used as raw materials to melt this glass with 1000 kg of quartz sand, how much of the other two raw materials are needed?", "answer": "With 1000 kg of quartz sand, the required soda ash (Na2CO3) is: (14/73)×1000×(106/62)=327.88 kg. The required limestone (CaCO3) is: (13/73)×1000×(100/56)=318.00 kg.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，以确定所需的原材料数量。答案中给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括质量百分比的转换、分子量的计算以及原料用量的推导。虽然不涉及复杂的机理分析或创新设计，但需要综合运用化学计量和材料组成知识，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解玻璃成分的化学计量关系，进行多步计算（包括分子量转换和比例计算），并综合分析原料与最终成分之间的关联。虽然题目提供了明确的解题路径，但涉及多个计算步骤和概念转换，对学生的应用能力和计算准确性要求较高。", "convertible": true, "correct_option": "327.88 kg of soda ash and 318.00 kg of limestone", "choice_question": "A glass composition (wt%) is Na2O 14%, CaO 13%, SiO2 73%, with a density of 2.5 g/cm3. If soda ash, limestone, and quartz sand are used as raw materials to melt this glass with 1000 kg of quartz sand, how much of the other two raw materials are needed?", "conversion_reason": "The calculation problem has a definite numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "327.88 kg of soda ash and 318.00 kg of limestone", "B": "245.91 kg of soda ash and 238.50 kg of limestone", "C": "409.85 kg of soda ash and 397.50 kg of limestone", "D": "163.94 kg of soda ash and 159.00 kg of limestone" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately calculates the required amounts based on molecular weight conversions and stoichiometry. Option B is a 75% scaling of the correct values, exploiting the tendency to underestimate raw material needs. Option C is a 125% scaling, playing on overcompensation bias. Option D is exactly half the correct values, a common error when misinterpreting batch calculations. All incorrect options maintain the correct ratio between materials to appear plausible.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3999, "question": "A structural component in the shape of a flat plate 27.3mm thick is to be fabricated from a metal alloy for which the yield strength and plane strain fracture toughness values are 535 MPa and 31.3 MPa·m^{-1 / 2}, respectively. For this particular geometry, the value of Y is 1.8 . Assuming a design stress of 0.5 times the yield strength, calculate the critical length of a surface flaw.", "answer": "the critical length of a surface flaw is 2.0 mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解临界表面缺陷长度，答案是一个具体的数值结果（2.0 mm），符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括设计应力的计算、临界裂纹长度的公式应用（涉及断裂韧性和几何因子Y的综合考虑），需要将多个概念关联起来进行综合分析。虽然不涉及复杂的推理或机理解释，但超出了简单直接套用公式的层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及多个步骤的计算，包括设计应力的计算、临界裂纹长度的计算，以及对材料性能参数的理解和应用。虽然题目提供了所有必要的参数，但解题过程需要综合运用这些参数进行多步计算，并正确应用相关公式。此外，题目还要求对材料的断裂力学有一定的理解，能够将理论知识与实际应用相结合。因此，在选择题型中，这道题的难度属于中等偏上。", "convertible": true, "correct_option": "2.0 mm", "choice_question": "A structural component in the shape of a flat plate 27.3mm thick is to be fabricated from a metal alloy for which the yield strength and plane strain fracture toughness values are 535 MPa and 31.3 MPa·m^{-1 / 2}, respectively. For this particular geometry, the value of Y is 1.8. Assuming a design stress of 0.5 times the yield strength, the critical length of a surface flaw is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.0 mm", "B": "4.1 mm", "C": "1.2 mm", "D": "3.7 mm" }, "correct_answer": "A", "explanation": "正确答案A是通过断裂力学公式a_c = (K_IC/(Y*σ*√π))^2计算得出，其中设计应力σ=0.5*535=267.5MPa。干扰项B是通过错误使用屈服强度而非设计应力计算得出；干扰项C来自错误地将厚度参数纳入计算；干扰项D则是混淆了平面应变和平面应力条件下的计算结果。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4299, "question": "A structural component in the form of a wide plate is to be fabricated from a steel alloy that has a plane strain fracture toughness of 77.0 MPa \\sqrt{m}(70.1 ksi \\sqrt{m}.) and a yield strength of 1400 MPa(205,000 psi). The flaw size resolution limit of the flaw detection apparatus is 4.0 mm(0.16 in.) If the design stress is one half of the yield strength and the value of Y is 1.0 , determine whether or not a critical flaw for this plate is subject to detection.", "answer": "the critical flaw size a_c is 3.9 mm. therefore, the critical flaw is not subject to detection since it is less than the 4.0 mm resolution limit.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定临界缺陷尺寸是否可被检测到。答案给出了具体的计算结果（3.9 mm），并基于计算结果进行了判断。 | 知识层次: 题目需要进行多步计算（临界裂纹尺寸计算、设计应力计算），并需要将计算结果与检测设备的限制进行比较分析。虽然公式直接给出，但需要正确应用并理解各参数之间的关系，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及平面应变断裂韧性、屈服强度、设计应力等多个材料科学概念，需要进行多步计算（包括临界裂纹尺寸的计算和与检测限度的比较）。虽然题目提供了正确选项，但解题过程需要综合应用多个知识点和公式推导，属于综合性计算问题。", "convertible": true, "correct_option": "the critical flaw is not subject to detection since it is less than the 4.0 mm resolution limit.", "choice_question": "A structural component in the form of a wide plate is to be fabricated from a steel alloy that has a plane strain fracture toughness of 77.0 MPa √m (70.1 ksi √m) and a yield strength of 1400 MPa (205,000 psi). The flaw size resolution limit of the flaw detection apparatus is 4.0 mm (0.16 in.). If the design stress is one half of the yield strength and the value of Y is 1.0, determine whether or not a critical flaw for this plate is subject to detection.", "conversion_reason": "The original question is a calculation problem with a definitive answer that can be converted into a multiple-choice format. The answer provides a clear conclusion that can serve as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical flaw is detectable because it exceeds the resolution limit when accounting for stress concentration effects", "B": "The critical flaw is not detectable because its calculated size is below the apparatus resolution limit", "C": "The critical flaw becomes detectable when considering the alloy's strain hardening behavior", "D": "The critical flaw detection depends on the plate thickness, which is not specified" }, "correct_answer": "B", "explanation": "The correct answer is B because calculation shows the critical flaw size (3.08 mm) is below the 4.0 mm detection limit. Option A exploits stress concentration misconception. Option C introduces irrelevant strain hardening concept. Option D creates false dependency on unspecified thickness parameter.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4745, "question": "For a brass alloy, the stress at which plastic deformation begins is 345 MPa (50,000 psi), and the modulus of elasticity is 103 GPa (15.0 x 10^6 psi). If the original specimen length is 76mm (3.0 in.), what is the maximum length to which it can be stretched without causing plastic deformation?", "answer": "the maximum length to which the specimen can be stretched without causing plastic deformation is 76.25mm (3.01 in.).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定最大拉伸长度，答案也是具体的数值结果。 | 知识层次: 题目涉及基本的应力-应变关系公式应用，即胡克定律（σ = Eε），需要计算弹性变形范围内的最大长度变化。计算过程直接，仅需一步公式应用和简单代数运算，无需多步推理或综合分析。 | 难度: 在选择题型内，该题目仅需要直接应用胡克定律（Hooke's Law）进行单一公式计算，即通过应力、弹性模量和原始长度计算最大弹性变形长度。解题步骤简单，无需组合多个公式或进行复杂分析，属于最基础的难度等级。", "convertible": true, "correct_option": "76.25mm (3.01 in.)", "choice_question": "For a brass alloy, the stress at which plastic deformation begins is 345 MPa (50,000 psi), and the modulus of elasticity is 103 GPa (15.0 x 10^6 psi). If the original specimen length is 76mm (3.0 in.), what is the maximum length to which it can be stretched without causing plastic deformation?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "76.25mm (3.01 in.)", "B": "76.34mm (3.006 in.)", "C": "76.50mm (3.012 in.)", "D": "76.10mm (2.996 in.)" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算弹性应变得出的：ε = σ/E = 345MPa/103GPa = 0.00335，ΔL = ε×L0 = 0.00335×76mm = 0.25mm。干扰项B利用了常见的单位换算错误（将psi直接转换为mm），干扰项C故意使用接近但超过屈服点的应变值，干扰项D则利用了反向计算误差（从错误假设的塑性变形开始点反推）。这些干扰项都针对AI可能出现的计算路径选择错误或单位处理不当的弱点。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2294, "question": "What role does the interface play in composite materials?", "answer": "The interface serves to coordinate the deformation of the matrix and the reinforcement. Through the interface, the stress from the matrix can be transferred to the reinforcement. The matrix and reinforcement are bonded via the interface, but the bonding strength must be appropriate—neither too strong nor too weak. Excessive bonding strength can reduce the toughness of the composite material, while insufficient bonding strength fails to transfer stress effectively, making the interface prone to cracking.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对复合材料中界面的作用进行文字解释和论述，答案提供了详细的描述和分析，符合简答题的特征。 | 知识层次: 题目考查对复合材料界面作用的综合理解，需要解释界面的功能、应力传递机制以及结合强度的影响，涉及多个概念的关联和综合分析。 | 难度: 在选择题型中，该题目要求考生不仅理解复合材料中界面的基本功能，还需要综合分析界面在应力传递、变形协调以及结合强度对材料性能的影响。题目涉及多个概念的关联（如应力传递、结合强度与韧性的关系），并要求考生在选项中进行多角度分析（如界面结合强度对材料性能的双重影响）。这种深度和广度的知识应用在选择题中属于较高难度，符合等级4的多角度分析论述标准。", "convertible": true, "correct_option": "The interface serves to coordinate the deformation of the matrix and the reinforcement. Through the interface, the stress from the matrix can be transferred to the reinforcement. The matrix and reinforcement are bonded via the interface, but the bonding strength must be appropriate—neither too strong nor too weak. Excessive bonding strength can reduce the toughness of the composite material, while insufficient bonding strength fails to transfer stress effectively, making the interface prone to cracking.", "choice_question": "What role does the interface play in composite materials?", "conversion_reason": "The answer is a standard explanation of the role of the interface in composite materials, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The interface primarily acts as a diffusion barrier to prevent chemical reactions between matrix and reinforcement", "B": "The interface serves to coordinate deformation by transferring stress, with optimal bonding strength that balances toughness and load transfer", "C": "The interface functions as a thermal expansion buffer to accommodate mismatch between components", "D": "The interface's main role is to provide electrical insulation between conductive reinforcements and matrix" }, "correct_answer": "B", "explanation": "The correct answer B captures the dual role of stress transfer and deformation coordination while emphasizing the critical aspect of bonding strength optimization. Option A exploits the common misconception about interface chemistry, while C uses a real but secondary function as the primary role. Option D introduces an unrelated property (electrical) that some interfaces may have but isn't fundamental to composite mechanics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3949, "question": "If an increased steady-state flow rate of O2 (oxygen molecules per second) to the cornea is desired, is increasing the ambient temperature likely to be useful? Note: the flow rate is equal to product of the diffusion flux and an area of interest through which diffusion occurs.", "answer": "Increasing the temperature should increase the diffusivity and therefore increase the diffusion flux and flow rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述温度对氧气扩散速率的影响，答案提供了文字解释而非选择、判断或计算。 | 知识层次: 题目需要理解扩散通量和流量的关系，并应用温度对扩散系数的影响来推导结果。这涉及到多步概念关联和综合分析，但不需要复杂的推理或深度理解。 | 难度: 在选择题中属于中等难度，需要理解扩散通量、温度对扩散系数的影响以及稳态流动速率之间的关系，并进行综合分析。虽然题目涉及多个概念，但解题步骤相对直接，不需要复杂的多角度分析或深度关联性分析。", "convertible": true, "correct_option": "Increasing the temperature should increase the diffusivity and therefore increase the diffusion flux and flow rate.", "choice_question": "If an increased steady-state flow rate of O2 (oxygen molecules per second) to the cornea is desired, is increasing the ambient temperature likely to be useful? Note: the flow rate is equal to product of the diffusion flux and an area of interest through which diffusion occurs.", "conversion_reason": "The answer is a clear and concise statement that can serve as a correct option in a multiple-choice question. The question can be converted by presenting this statement as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because higher temperature increases oxygen diffusivity through the Arrhenius relationship", "B": "No, because higher temperature would decrease oxygen solubility in the cornea tissue according to Henry's law", "C": "Only if the temperature increase is accompanied by higher humidity to prevent corneal dehydration", "D": "No, because the diffusion area would decrease due to thermal expansion of corneal proteins" }, "correct_answer": "A", "explanation": "The correct answer is A because diffusivity follows an Arrhenius-type temperature dependence, where higher temperatures increase molecular mobility. Option B is a cognitive bias trap - while Henry's law is valid for solubility, it's irrelevant to diffusion-controlled flow rate. Option C exploits medical intuition about corneal hydration but is irrelevant to the diffusion mechanism. Option D creates a false correlation between thermal expansion and diffusion area that doesn't exist in this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 556, "question": "Given: When the grain size of annealed pure iron is 16 per $\\mathbf{\\chi}_{\\mathbf{m}\\mathbf{m}^{2}}$, the yield strength $\\sigma_{\\mathsf{s}}=100\\mathrm{N/\\Omega}$ $\\mathbf{m}\\mathbf{m}^{2}$; when the grain size is 4096 per $\\prime_{\\mathbf{m}\\mathbf{m}^{2}}$, $\\sigma_{\\mathrm{s}}=250\\mathrm{N}/\\mathrm{mm}^{2}$. Find the value of yield strength $\\pmb{\\sigma_{\\S}}$ when the grain size is 256 per $\\mathbf{m}\\mathbf{m}^{2}$.", "answer": "According to the Hall-Petch formula: $\\sigma_{\\mathrm{s}}=\\sigma_{0}+K_{\\mathrm{y}}d^{-1/2}$, the yield strength $\\sigma_{\\mathbf{s}}$ of the material is calculated from the average grain size $^d$. Expressing the grain size in terms of the radius of an equal-area circle: $$d_{1}=(4A_{1}/\\pi)^{1/2}d_{2}=(4A_{2}/\\pi)^{1/2}$$$A_{1}$ and $A_{2}$ are the grain areas. Thus, $$\\sigma_{\\mathrm{s1}}=\\sigma_{0}+K_{\\mathrm{y}}d_{1}^{-1/2}\\sigma_{\\mathrm{s2}}=\\sigma_{0}+K_{\\mathrm{y}}d_{2}^{-1/2}$$Given that $A_{1}=1/16\\mathrm{mm}^{2}$, $A_{2}=1/4096\\mathrm{mm}^{2}$, $\\sigma_{\\mathrm{s}1}=100\\mathrm{N/mm}^{2}$, $\\sigma_{\\mathrm{s}2}=250\\mathrm{N}/\\mathrm{mm}^{2}$, substituting into the above equations yields $K_{\\mathrm{y}}=25{\\sqrt{2}}\\pi^{-1/4}\\mathrm{N}/\\mathrm{mm}^{3/2}$, $\\pmb{\\sigma_{0}}=50\\mathbf{N}/\\mathbf{m}\\mathbf{m}^{2}$. Then, with $A_{3}=1/256\\mathrm{mm}^{2}$, we find $\\sigma_{\\mathbf{s}3}=150\\mathbf{N}/\\mathbf{m}\\mathbf{m}^{2}$. (10 points)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的数据和公式（Hall-Petch公式）进行数值计算，最终得出一个具体的数值结果（yield strength的值）。解答过程涉及公式应用和代数运算，符合计算题的特征。 | 知识层次: 题目需要应用Hall-Petch公式进行多步计算，涉及不同晶粒尺寸下的屈服强度计算，需要理解公式中各参数的含义并进行数值代入和求解。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力和概念关联。 | 难度: 在选择题中属于中等偏上难度，需要理解Hall-Petch公式并正确应用，涉及多步计算和单位转换。虽然题目提供了部分已知条件，但仍需进行综合分析才能得出最终答案。", "convertible": true, "correct_option": "150 N/mm²", "choice_question": "Given: When the grain size of annealed pure iron is 16 per mm², the yield strength σₛ = 100 N/mm²; when the grain size is 4096 per mm², σₛ = 250 N/mm². Find the value of yield strength σₛ when the grain size is 256 per mm².", "conversion_reason": "The problem provides a clear calculation path leading to a specific numerical answer, making it suitable for conversion to a multiple-choice question format with the correct option being the calculated yield strength.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "150 N/mm²", "B": "175 N/mm²", "C": "200 N/mm²", "D": "125 N/mm²" }, "correct_answer": "A", "explanation": "正确答案A基于Hall-Petch关系σₛ=σ₀+kd^(-1/2)计算得出。干扰项B利用线性插值直觉错误；C利用对数坐标直觉错误；D反向应用Hall-Petch关系错误。先进AI可能因忽视晶界强化非线性本质而误选B或C。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3883, "question": "Materials Science and Engineering is the study of material behavior & performance and how this is simultaneously related to structure, properties, and processing. Which of the following is the best example of material processing?(a) Extrusion(b) Crystalline(c) Amorphous(d) Glassy (e) Elastic Modulus", "answer": "(a)Extrusion", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择最佳答案，符合选择题的特征 | 知识层次: 题目考查对材料加工基本概念的识别和记忆，只需从选项中选出与材料加工相关的术语，不需要复杂的分析或推理。 | 难度: 在选择题型中属于简单难度，题目直接考察对\"材料加工\"这一基础概念的识别能力。正确选项(a)Extrusion是材料加工的典型示例，而其他选项都是材料结构或性能的描述。这只需要最基本的定义记忆即可作答，无需理解或辨析过程。", "convertible": true, "correct_option": "Extrusion", "choice_question": "Materials Science and Engineering is the study of material behavior & performance and how this is simultaneously related to structure, properties, and processing. Which of the following is the best example of material processing?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hot isostatic pressing of titanium alloy powder at 900°C under 100MPa argon pressure", "B": "The {111} slip system activation in FCC aluminum single crystal under tensile stress", "C": "The 0.2% offset yield strength measurement of annealed copper", "D": "The Hall-Petch relationship observed in nanocrystalline nickel" }, "correct_answer": "A", "explanation": "The correct answer is A because hot isostatic pressing is a clear example of material processing that alters microstructure through simultaneous heat and pressure. Option B describes a deformation mechanism (slip system activation), not processing. Option C is a material property measurement technique. Option D describes a structure-property relationship. The difficulty lies in distinguishing between actual processing techniques (A) versus fundamental phenomena (B,D) or characterization methods (C), particularly when all options involve specific material systems and quantitative parameters that may trigger AI's pattern matching toward more 'scientific-sounding' options.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3056, "question": "What can SiC ceramics be used for? Options: A. Grinding wheel B. Blade C. Cutting tool D. Abrasive E. Crucible", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择正确答案 | 知识层次: 题目考查对SiC陶瓷用途的基本概念记忆，属于基础知识的直接回忆和识别，不需要复杂的分析或综合应用。 | 难度: 该题目属于基础概念记忆层次，仅需识别SiC陶瓷的基本用途。选项B（Blade）是直接记忆性知识点，无需复杂分析或概念辨析，符合等级1的简单概念识别标准。", "convertible": true, "correct_option": "B", "choice_question": "What can SiC ceramics be used for?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High-temperature structural components in aerospace engines", "B": "Primary load-bearing elements in civil engineering bridges", "C": "Biocompatible implants for orthopedic applications", "D": "Transparent optical windows for infrared systems" }, "correct_answer": "A", "explanation": "Correct answer A is justified because SiC ceramics exhibit exceptional thermal stability and mechanical strength at high temperatures, making them ideal for aerospace applications. Option B exploits the cognitive bias of associating ceramics with construction materials, while ignoring SiC's brittleness in tensile loading. Option C creates a professional intuition trap by referencing ceramic biocompatibility (true for alumina/zirconia but not SiC). Option D uses a multi-level verification trap - while SiC does have good IR transmission, achieving optical transparency requires single-crystal forms not typical for structural ceramics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2154, "question": "For a face-centered cubic crystal with a movable slip system of (111)[110], indicate the direction of dislocation line movement during slip in the cases of pure edge dislocation and pure screw dislocation.", "answer": "In the case of pure edge dislocation, the direction of dislocation line movement is parallel to b; in the case of pure screw dislocation, the direction of dislocation line movement is perpendicular to b.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和描述纯刃型位错和纯螺型位错在位错线移动时的方向，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求分析面心立方晶体中特定滑移系统下纯刃型位错和纯螺型位错的运动方向，需要理解位错类型与运动方向的关系，并能够将这一知识应用到具体晶体结构中。这涉及多步概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题型中，该题目属于较高难度，需要考生具备以下能力：", "convertible": true, "correct_option": "In the case of pure edge dislocation, the direction of dislocation line movement is parallel to b; in the case of pure screw dislocation, the direction of dislocation line movement is perpendicular to b.", "choice_question": "For a face-centered cubic crystal with a movable slip system of (111)[110], indicate the direction of dislocation line movement during slip in the cases of pure edge dislocation and pure screw dislocation. Which of the following is correct?", "conversion_reason": "The answer is a standard description that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In the case of pure edge dislocation, the direction of dislocation line movement is parallel to b; in the case of pure screw dislocation, the direction of dislocation line movement is perpendicular to b", "B": "In both cases, the direction of dislocation line movement is parallel to b", "C": "In the case of pure edge dislocation, the direction of dislocation line movement is perpendicular to b; in the case of pure screw dislocation, the direction of dislocation line movement is parallel to b", "D": "In both cases, the direction of dislocation line movement is perpendicular to b" }, "correct_answer": "A", "explanation": "The correct answer is A because for edge dislocations, the dislocation line moves parallel to the Burgers vector (b) as the extra half-plane moves, while for screw dislocations, the dislocation line moves perpendicular to b as the crystal planes shear. Option B is incorrect as it oversimplifies both cases. Option C reverses the correct relationships, exploiting common confusion between edge and screw dislocation behavior. Option D is incorrect but plausible as it maintains symmetry in both cases, appealing to intuitive but wrong symmetry considerations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3496, "question": "What method is used to strengthen austenitic stainless steel in production?", "answer": "Work hardening is commonly used to strengthen it in production.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释哪种方法用于强化奥氏体不锈钢，答案提供了文字解释而非选择或判断，符合简答题的特征。 | 知识层次: 题目考查对奥氏体不锈钢强化方法的基础概念记忆，即冷加工硬化（work hardening）这一基本原理的应用。 | 难度: 在选择题型中，此题仅需记忆基础概念（奥氏体不锈钢的强化方法），属于最简单的定义性知识考察。题目直接给出正确选项\"work hardening\"，不需要任何解释或分析步骤，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Work hardening", "choice_question": "Which method is used to strengthen austenitic stainless steel in production?", "conversion_reason": "The answer is a standard term (Work hardening) which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Work hardening", "B": "Precipitation hardening", "C": "Grain boundary strengthening", "D": "Solid solution strengthening" }, "correct_answer": "A", "explanation": "The correct answer is A because austenitic stainless steels cannot be strengthened by heat treatment (like precipitation hardening) due to their stable austenitic structure, making work hardening the primary method. Option B is a trap as precipitation hardening is commonly used for other stainless steels but not austenitic. Option C exploits the intuitive appeal of grain boundary effects, which are secondary in this context. Option D is plausible but incorrect because while solid solution strengthening contributes to initial strength, it's not the primary production method for significant strengthening.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1102, "question": "Calculate the planar density of the (111) plane in a face-centered cubic crystal, given the atomic radius r=(√2/4)a", "answer": "For the (111) plane of a face-centered cubic crystal, there are 2 atoms. The planar density is calculated as: 2π(√2/4 a)^2 / (1/2 √2 a×√2 a×sin60°) = 2π×1/8 / (√3/2) = π/(2√3) = 0.90", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及具体的数学运算和物理公式的使用，最终给出一个数值结果。 | 知识层次: 题目需要应用面心立方晶体的几何关系和平面密度的计算公式，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解面心立方晶体结构、(111)晶面的原子排布、平面密度计算公式等多个概念，并进行多步计算和综合分析。虽然题目提供了部分计算步骤，但仍需要较强的空间想象能力和数学计算能力才能正确解答。", "convertible": true, "correct_option": "0.90", "choice_question": "What is the planar density of the (111) plane in a face-centered cubic crystal, given the atomic radius r=(√2/4)a?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.90", "B": "0.78", "C": "1.15", "D": "0.58" }, "correct_answer": "A", "explanation": "The correct answer is A (0.90) because the planar density of the (111) plane in an FCC crystal is calculated as (number of atoms in the plane)/(area of the plane). For FCC (111), there are 2 full atoms within the hexagonal plane area of (√3/2)a², giving 2/(√3/2)a² = 4/(√3a²). Substituting a=4r/√2 gives 0.90. Option B (0.78) exploits the common mistake of using the wrong plane area calculation. Option C (1.15) targets confusion between planar and linear density. Option D (0.58) is designed to trap those who miscalculate the number of atoms in the plane.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4882, "question": "Why must fiber materials that are melt-spun be thermoplastic?", "answer": "Fiber materials that are melt spun must be thermoplastic because they must be capable of forming a viscous liquid when heated, which is not possible for thermosets.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释为什么熔纺纤维材料必须是热塑性的，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对热塑性材料基本特性的记忆和理解，即为什么熔融纺丝的材料必须是热塑性的。这属于基础概念的记忆和简单解释，不需要复杂的分析或综合。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并区分热塑性材料和热固性材料的特性，并能够解释为什么熔融纺丝必须使用热塑性材料。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或比较（等级3）。", "convertible": true, "correct_option": "They must be capable of forming a viscous liquid when heated, which is not possible for thermosets.", "choice_question": "Why must fiber materials that are melt-spun be thermoplastic?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "They must be capable of forming a viscous liquid when heated, which is not possible for thermosets", "B": "Thermoplastics have higher crystallinity which is essential for fiber strength", "C": "The melt-spinning process requires reversible phase transitions only possible in thermoplastics", "D": "Thermosets cannot achieve the necessary viscosity for fiber formation at any temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because melt-spinning fundamentally requires the material to melt into a viscous liquid, a property exclusive to thermoplastics. B is incorrect because crystallinity is not a fundamental requirement for melt-spinning (many amorphous thermoplastics can be melt-spun). C is a cognitive bias trap - while phase transition reversibility is true for thermoplastics, it's not the core reason for melt-spinning suitability. D is a professional intuition trap - while generally true, some thermosets can achieve fiber-forming viscosity before crosslinking completes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1531, "question": "Explain the strengthening mechanism of work hardening", "answer": "Work hardening: During the plastic deformation of cold-worked metals, a large number of dislocations are formed. Some of these dislocations become immobile dislocations, thereby increasing their resistance to mobile dislocations. This makes further deformation of the material difficult, resulting in work hardening or strain hardening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释加工硬化的强化机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释加工硬化的强化机制，涉及位错的形成、运动及其相互作用等复杂概念，需要综合运用材料科学中的位错理论和塑性变形知识进行机理层面的分析和解释。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求深入理解位错理论、塑性变形机制以及加工硬化的微观机理，并能够将这些复杂概念整合起来进行综合解释。这需要考生具备扎实的材料科学基础，能够将抽象的理论知识与实际现象联系起来，属于复杂现象的全面分析层次。在选择题型中，这类需要深度机理解释和综合分析的题目通常是最具挑战性的。", "convertible": true, "correct_option": "Work hardening: During the plastic deformation of cold-worked metals, a large number of dislocations are formed. Some of these dislocations become immobile dislocations, thereby increasing their resistance to mobile dislocations. This makes further deformation of the material difficult, resulting in work hardening or strain hardening.", "choice_question": "Which of the following best describes the strengthening mechanism of work hardening?", "conversion_reason": "The answer is a standard explanation of the concept of work hardening, which can be presented as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Work hardening occurs due to the formation of immobile dislocation tangles that impede further dislocation motion", "B": "Work hardening results from the reduction in grain size during cold working, increasing grain boundary strengthening", "C": "Work hardening is caused by the precipitation of secondary phases that block dislocation movement", "D": "Work hardening arises from the alignment of dislocations into low-energy configurations that resist deformation" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual mechanism where dislocation tangles form during plastic deformation, creating barriers to further dislocation motion. Option B incorrectly attributes work hardening to grain refinement (Hall-Petch effect). Option C describes precipitation hardening rather than work hardening. Option D describes dislocation cell formation which occurs at later stages but isn't the primary strengthening mechanism. Advanced AI might confuse these similar but distinct strengthening mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3656, "question": "Suppose we introduce one carbon atom for every 100 iron atoms in an interstitial position in BCC iron, giving a lattice parameter of 0.2867 nm. For the Fe-C alloy, find the density.", "answer": "7.89 g/cm³", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解Fe-C合金的密度，答案是一个具体的数值（7.89 g/cm³），这表明解答过程需要涉及材料科学中的密度计算公式和单位转换等计算步骤。 | 知识层次: 题目需要进行多步计算，包括确定晶胞中的原子数、计算晶胞质量、体积以及最终的密度计算。虽然不涉及复杂的机理分析或创新设计，但需要综合运用晶体结构、原子质量和密度计算等知识，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要综合运用晶体结构、原子质量和密度计算的知识。解题步骤包括：1) 理解BCC铁的单位晶胞原子数；2) 计算掺杂碳后的晶胞质量；3) 利用晶格参数计算晶胞体积；4) 综合计算密度。虽然题目给出了关键参数（晶格常数），但仍需进行多步计算和单位换算，且需要正确理解间隙固溶体的概念。相比简单回忆型选择题，这需要更高层次的应用能力。", "convertible": true, "correct_option": "7.89 g/cm³", "choice_question": "Suppose we introduce one carbon atom for every 100 iron atoms in an interstitial position in BCC iron, giving a lattice parameter of 0.2867 nm. For the Fe-C alloy, the density is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice in a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.89 g/cm³", "B": "8.02 g/cm³", "C": "7.65 g/cm³", "D": "7.93 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer is A (7.89 g/cm³) because it accounts for the precise atomic mass and volume changes due to carbon interstitial insertion in BCC iron. Option B (8.02 g/cm³) is a cognitive bias trap that overestimates the density by assuming FCC packing efficiency. Option C (7.65 g/cm³) exploits the intuitive error of subtracting carbon's effect rather than adding it. Option D (7.93 g/cm³) is a professional intuition trap using the density of pure iron at room temperature, ignoring the carbon's impact.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2689, "question": "Given that the number-average relative molecular weight of linear polytetrafluoroethylene is 5×10^5, its C-C bond length is 0.154 nm, and the bond angle θ is 109°, calculate its root-mean-square length.", "answer": "The root-mean-square length r=d√N=0.154×√(1.0×10^4)=15.4 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的参数（分子量、键长、键角）应用公式计算均方根长度，答案呈现为具体的数值计算结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括理解根均方长度的概念、应用相关公式（r=d√N）以及进行数值计算。虽然不涉及复杂的综合分析或推理，但需要将多个概念（如键长、键角和分子量）关联起来进行计算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解高分子链的均方根末端距计算公式（r=d√N），并正确关联题目给出的参数（键长d=0.154 nm、聚合度N=5×10^5/100=5×10^3）。虽然计算步骤明确（先求聚合度再开方计算），但需要综合应用高分子物理知识和三角函数计算（109°键角隐含的投影关系），且涉及数量级转换（将5×10^5分子量转换为聚合度）。相比简单概念选择题（等级1）或单步计算题（等级2），该题需要更系统的知识整合能力。", "convertible": true, "correct_option": "15.4 nm", "choice_question": "Given that the number-average relative molecular weight of linear polytetrafluoroethylene is 5×10^5, its C-C bond length is 0.154 nm, and the bond angle θ is 109°, its root-mean-square length is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "15.4 nm", "B": "24.7 nm", "C": "7.8 nm", "D": "31.2 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (15.4 nm) because it is calculated using the formula for root-mean-square length of a polymer chain: sqrt(n) * l * sqrt((1 - cosθ)/(1 + cosθ)), where n is the degree of polymerization, l is the bond length, and θ is the bond angle. Option B (24.7 nm) is designed to exploit the common mistake of forgetting to take the square root of the degree of polymerization. Option C (7.8 nm) is based on the error of using the wrong bond angle (180° instead of 109°). Option D (31.2 nm) is a trap for those who incorrectly use the weight-average molecular weight instead of the number-average.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1944, "question": "For metals without phase transformation in the solid state, if not remelted, how to refine grains through cold deformation and recrystallization?", "answer": "By performing significant cold deformation followed by recrystallization at an appropriate temperature to obtain fine grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案提供了详细的步骤和方法，而不是简单的选择或判断。 | 知识层次: 题目需要理解冷变形和再结晶的基本原理，并能够将这两个概念关联起来，综合分析如何通过这两个步骤细化晶粒。这涉及到多步的知识应用和概念关联，而不仅仅是简单的记忆或直接套用。 | 难度: 在选择题中属于中等难度，需要理解金属冷变形和再结晶的基本概念，并能将这两个过程关联起来综合分析其对晶粒细化的影响。题目要求考生不仅知道冷变形和再结晶的单独作用，还要理解它们结合使用的效果，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "By performing significant cold deformation followed by recrystallization at an appropriate temperature to obtain fine grains.", "choice_question": "For metals without phase transformation in the solid state, if not remelted, how to refine grains through cold deformation and recrystallization?", "conversion_reason": "The answer is a standard procedure and can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "By performing significant cold deformation followed by recrystallization at an appropriate temperature to obtain fine grains", "B": "By heating the metal to just below its melting point to allow natural grain refinement through surface tension effects", "C": "Through repeated cycles of rapid quenching and tempering to induce grain boundary migration", "D": "By applying high-frequency ultrasonic vibrations during cold deformation to break up existing grain structures" }, "correct_answer": "A", "explanation": "The correct answer is A because cold deformation introduces dislocations and stored energy, while subsequent recrystallization at an appropriate temperature allows new strain-free grains to nucleate and grow. Option B is incorrect because heating near melting point would cause grain growth rather than refinement. Option C is a trap for those confusing this process with heat treatment of steels. Option D exploits the common misconception that external energy inputs can directly refine grains without proper thermal treatment.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 378, "question": "Habit plane", "answer": "During solid-state phase transformation, the new phase often begins to form on certain crystallographic planes of the parent phase, which are called habit planes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Habit plane\"进行文字解释和论述，答案提供了详细的定义和背景说明，符合简答题的特征。 | 知识层次: 题目考查对\"habit plane\"这一基本概念的定义和简单解释，属于基础概念的记忆和理解范畴，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即“habit plane”的定义。正确选项直接给出了定义，没有涉及复杂的概念体系或需要解释和描述的内容。因此，属于基本定义简答的难度等级。", "convertible": true, "correct_option": "During solid-state phase transformation, the new phase often begins to form on certain crystallographic planes of the parent phase, which are called habit planes.", "choice_question": "What are habit planes in the context of solid-state phase transformation?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystallographic planes in the parent phase where the new phase preferentially forms", "B": "The interface planes with minimum surface energy between parent and product phases", "C": "Planes of maximum atomic density in the parent phase", "D": "The most elastically compliant planes in the parent phase" }, "correct_answer": "A", "explanation": "The correct answer is A because habit planes are specifically defined as the crystallographic planes in the parent phase where the new phase nucleates and grows. Option B is a cognitive bias trap - while surface energy minimization is important, it's not the defining characteristic of habit planes. Option C exploits the common intuition about high-density planes being nucleation sites, but this isn't universally true. Option D is a professional intuition trap - elastic compliance affects transformation but doesn't define habit planes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2482, "question": "Comment on the possibility of classical nucleation. It is known that the dislocation density of heavily worked metallic materials is approximately 10^15 m^-2.", "answer": "The dislocation density of heavily worked metallic materials is approximately 10^15 m^-2, making the formation of a critical nucleus of such size essentially impossible. The critical nucleus radius for classical nucleation discussed above is 5×10^-7 m, clearly indicating that nucleation cannot occur via the classical nucleation mechanism.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对经典成核的可能性进行评论，答案提供了详细的文字解释和论述，没有涉及计算、选择或判断对错。 | 知识层次: 题目要求对经典成核理论的可能性进行评论，需要结合位错密度和临界核半径的概念进行综合分析，涉及多知识点的关联和推理分析，思维过程深度较高。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅要掌握经典成核理论的基本概念，还需要理解位错密度对成核过程的影响机制。正确选项涉及复杂的定量比较（10^15 m^-2位错密度与5×10^-7 m临界核半径的对比），需要考生进行跨尺度的物理概念整合和机理推理。此外，题目要求将材料加工状态（剧烈变形金属）与成核理论相结合，体现了对复杂现象的综合分析能力，这完全符合等级5\"复杂现象全面分析\"的标准。在选择题型中，这种需要多维度知识整合和定量分析的题目属于最具挑战性的类型。", "convertible": true, "correct_option": "The dislocation density of heavily worked metallic materials is approximately 10^15 m^-2, making the formation of a critical nucleus of such size essentially impossible. The critical nucleus radius for classical nucleation discussed above is 5×10^-7 m, clearly indicating that nucleation cannot occur via the classical nucleation mechanism.", "choice_question": "Comment on the possibility of classical nucleation given that the dislocation density of heavily worked metallic materials is approximately 10^15 m^-2.", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice structure by focusing on the key concept being asked.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Classical nucleation is impossible because the required critical nucleus size exceeds the average dislocation spacing", "B": "Classical nucleation is enhanced due to the high dislocation density providing preferential nucleation sites", "C": "Classical nucleation remains unaffected as dislocations primarily influence growth rather than nucleation", "D": "Classical nucleation becomes possible only when the dislocation density exceeds 10^16 m^-2" }, "correct_answer": "A", "explanation": "The correct answer is A because the average dislocation spacing at 10^15 m^-2 is about 10^-7.5 m, which is smaller than the critical nucleus radius of 5×10^-7 m, making classical nucleation impossible. Option B is a cognitive bias trap, as dislocations can aid nucleation but not when the critical nucleus exceeds the available space. Option C exploits the common misconception that dislocations only affect growth. Option D uses a plausible-sounding but arbitrary threshold value to mislead.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1171, "question": "Martensite is a supersaturated solid solution of carbon in what?", "answer": "α-Fe", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的知识点（马氏体的组成），答案是一个简短的专业术语（α-Fe），不需要计算或选择，属于简答题类型。 | 知识层次: 题目考查马氏体的基本定义和组成，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 该题目属于基础概念记忆类型，仅需识别马氏体的基本定义（碳在α-Fe中的过饱和固溶体）。选择题型中仅需从选项中选出正确术语，无需解释或推理，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "α-Fe", "choice_question": "Martensite is a supersaturated solid solution of carbon in which of the following?", "conversion_reason": "The answer is a standard term (α-Fe), making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "α-Fe", "B": "γ-Fe", "C": "Fe3C", "D": "δ-Fe" }, "correct_answer": "A", "explanation": "Martensite is a supersaturated solid solution of carbon in α-Fe (ferrite). The key confusion comes from the fact that martensite forms from γ-Fe (austenite) during rapid quenching, but the carbon is actually supersaturated in the α-Fe lattice. Option B (γ-Fe) exploits the cognitive bias of associating martensite with its parent phase. Option C (Fe3C) is a trap for those confusing martensite with its decomposition product (cementite). Option D (δ-Fe) targets those who mistake the high-temperature ferrite phase for the room-temperature α-Fe.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3783, "question": "Based on Hume-Rothery's conditions, would the system Mg-Cd be expected to display unlimited solid solubility? Explain.", "answer": "Yes", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求基于Hume-Rothery条件解释Mg-Cd系统是否显示无限固溶度，需要文字解释和论述，而不仅仅是选择或判断对错。答案\"Yes\"只是结论的一部分，完整的回答还需要解释原因。 | 知识层次: 题目要求基于Hume-Rothery规则分析Mg-Cd系统的固溶度问题，需要理解并应用多个条件（如原子尺寸、电负性、晶体结构等）进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解Hume-Rothery规则中的多个条件（如原子尺寸差、电负性、价电子浓度等），并将这些概念综合应用到Mg-Cd体系中进行分析判断。虽然题目给出了正确选项，但解答过程需要多步概念关联和综合分析，符合等级3的综合分析和说明要求。", "convertible": true, "correct_option": "Yes", "choice_question": "Based on Hume-Rothery's conditions, would the system Mg-Cd be expected to display unlimited solid solubility?", "conversion_reason": "The answer is a standard term (Yes/No), which can be converted into a multiple-choice question format with 'Yes' as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, due to nearly identical atomic radii and crystal structures", "B": "No, because Mg has significantly higher electronegativity than Cd", "C": "Only at high temperatures where entropy dominates", "D": "No, due to their different positions in the periodic table" }, "correct_answer": "A", "explanation": "Correct answer A is justified because Mg-Cd meets all Hume-Rothery conditions: (1) atomic size difference <15% (Mg:1.60Å, Cd:1.71Å), (2) same HCP structure, (3) similar electronegativity (Mg:1.31, Cd:1.69), and (4) same valence. Option B exploits electronegativity misconception - while different, the difference is within acceptable limits. Option C creates false temperature dependence - solubility is intrinsic, not temperature-driven. Option D leverages periodic table position bias, though this isn't a Hume-Rothery criterion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 627, "question": "According to the solidification theory, analyze the characteristics of typical ingot structure", "answer": "The typical ingot structure features fine equiaxed crystals in the outer layer, columnar crystals extending inward from the surface, and coarse equiaxed crystals in the center.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求根据凝固理论分析典型铸锭结构的特征，答案以文字解释和论述的形式呈现，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求根据凝固理论分析典型铸锭结构的特征，需要理解并应用凝固理论的基本原理，关联不同晶体结构的形成原因，并进行综合分析。这超出了单纯记忆基础概念的层次，但尚未达到复杂分析或高级综合的要求。 | 难度: 在选择题中属于中等难度，需要理解典型铸锭结构的三个主要特征（外层细等轴晶、中间柱状晶和中心粗等轴晶），并能将这些特征与凝固理论的基本原理联系起来。虽然不需要进行多步计算，但需要对凝固过程中的晶体生长机制有较好的理解，并能综合分析不同区域的晶体形态差异。", "convertible": true, "correct_option": "The typical ingot structure features fine equiaxed crystals in the outer layer, columnar crystals extending inward from the surface, and coarse equiaxed crystals in the center.", "choice_question": "According to the solidification theory, which of the following describes the characteristics of a typical ingot structure?", "conversion_reason": "The answer is a standard description of the typical ingot structure, which can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The typical ingot structure features fine equiaxed crystals in the outer layer, columnar crystals extending inward from the surface, and coarse equiaxed crystals in the center", "B": "The typical ingot structure consists of uniformly distributed columnar crystals throughout, with no distinct zoning pattern", "C": "The typical ingot structure shows coarse equiaxed crystals in the outer layer and fine columnar crystals in the center", "D": "The typical ingot structure exhibits alternating layers of fine and coarse equiaxed crystals due to periodic cooling rate variations" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the classic three-zone ingot structure resulting from directional solidification. Option B is wrong because it ignores the fundamental cooling gradient that creates zoning. Option C reverses the actual crystal distribution pattern, exploiting a common memory inversion error. Option D introduces a plausible-sounding but non-existent periodic pattern, playing on the AI's tendency to overcomplicate periodic phenomena in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3430, "question": "What are the forms of alloying elements in steel?", "answer": "The forms of alloying elements in steel are: (1) dissolved in ferrite, austenite, or martensite, existing as solute; (2) forming strengthening phases; (3) existing in a free state; (4) forming non-metallic inclusions with impurities such as oxygen, nitrogen, and sulfur in the steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释合金元素在钢中的存在形式，答案提供了详细的文字描述和分类，符合简答题的特征。 | 知识层次: 题目考查合金元素在钢中存在形式的基本分类和记忆，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解和记忆合金元素在钢中的四种存在形式，包括溶解在铁素体、奥氏体或马氏体中作为溶质、形成强化相、以自由状态存在以及与杂质形成非金属夹杂物。这要求考生不仅记住定义，还需要对合金元素的不同存在形式有一定的理解和分类能力。因此，相较于仅需记忆单一定义的题目（等级1），该题目需要更深入的概念解释和描述能力（等级2）。", "convertible": true, "correct_option": "The forms of alloying elements in steel are: (1) dissolved in ferrite, austenite, or martensite, existing as solute; (2) forming strengthening phases; (3) existing in a free state; (4) forming non-metallic inclusions with impurities such as oxygen, nitrogen, and sulfur in the steel.", "choice_question": "Which of the following correctly describes the forms of alloying elements in steel?", "conversion_reason": "The answer is a standard description of the forms of alloying elements in steel, which can be converted into a multiple-choice question format by presenting the answer as one of the options and rephrasing the question to fit a selection format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dissolved in matrix phases, forming strengthening precipitates, existing as free elements, and forming non-metallic inclusions", "B": "Only dissolved in austenite and forming carbides, with no free state possible", "C": "Exclusively forming intermetallic compounds and never dissolving in the matrix", "D": "Always forming solid solutions with iron and never creating inclusions" }, "correct_answer": "A", "explanation": "The correct answer A comprehensively covers all possible forms of alloying elements in steel. Option B is incorrect because it ignores the possibility of elements dissolving in ferrite/martensite and existing in free state. Option C is wrong as it denies the fundamental solubility of alloying elements. Option D is incorrect by asserting all elements form solid solutions and ignoring inclusion formation. Advanced AIs may be misled by oversimplified metallurgical assumptions in B-D.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 404, "question": "Grain boundary", "answer": "Grain boundary: The region of atomic misalignment at the interface where two grains meet.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Grain boundary\"进行文字解释和论述，答案提供了详细的定义说明，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即晶界的定义，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别晶界的基本定义，属于最基础的概念记忆层次。题目直接给出了正确选项的定义，无需进行复杂的概念比较或分析，因此难度等级为1。", "convertible": true, "correct_option": "The region of atomic misalignment at the interface where two grains meet.", "choice_question": "Which of the following best describes a grain boundary?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The region of atomic misalignment at the interface where two grains meet", "B": "A planar defect characterized by a sudden change in crystallographic orientation", "C": "The transition zone where dislocations accumulate between adjacent crystals", "D": "A two-dimensional defect formed by the termination of a crystal plane" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines grain boundaries as regions of atomic misalignment between grains. Option B is a cognitive bias trap - while grain boundaries do involve orientation changes, this describes twist boundaries specifically. Option C exploits professional intuition by mixing dislocation concepts incorrectly. Option D is a multi-level trap that partially describes stacking faults rather than grain boundaries.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1990, "question": "If the dislocation density in a certain crystal is known to be ρ=10^6~10^7 cm/cm^3, and the average length of F-R dislocation sources measured experimentally is 10^-4 cm, determine the number of F-R dislocation sources in the dislocation network.", "answer": "Assuming that the dislocation lines in the crystal are entangled and mutually pinned, the possible number of dislocation sources is n= ρ/L=10^10~10^11 per cm^3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的数值和公式进行计算，以确定F-R位错源的数量。答案是通过数值计算得出的具体数值范围，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过已知的位错密度和平均长度直接套用公式n=ρ/L进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用一个基本公式（n= ρ/L）进行计算，无需多个公式组合或复杂分析。属于单一公式直接计算的难度等级。", "convertible": true, "correct_option": "n=10^10~10^11 per cm^3", "choice_question": "If the dislocation density in a certain crystal is known to be ρ=10^6~10^7 cm/cm^3, and the average length of F-R dislocation sources measured experimentally is 10^-4 cm, determine the number of F-R dislocation sources in the dislocation network.", "conversion_reason": "The answer is a specific numerical range, which can be presented as an option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "n=10^10~10^11 per cm^3", "B": "n=10^6~10^7 per cm^3", "C": "n=10^2~10^3 per cm^3", "D": "n=10^14~10^15 per cm^3" }, "correct_answer": "A", "explanation": "The correct answer is A because the number of F-R sources (n) is calculated by dividing the dislocation density (ρ) by the average length of F-R sources (L), giving n=ρ/L. With ρ=10^6~10^7 cm/cm^3 and L=10^-4 cm, n=10^10~10^11 per cm^3. Option B is a cognitive bias trap, directly using the dislocation density value without considering the length factor. Option C is a professional intuition trap, suggesting an unrealistically low number that might seem plausible for special cases. Option D is a multi-level verification trap, presenting values typical for atomic density rather than dislocation sources.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1897, "question": "8.The characteristic of reversible polymorphic transformation is: (23)", "answer": "(23) The polymorphic transformation temperature is lower than the melting points of both crystal forms", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案，答案以选项编号(23)给出，符合选择题的特征 | 知识层次: 题目考查可逆多晶型转变的基本特征，属于对基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 该题目属于基础概念记忆层次，要求考生掌握可逆多晶型转变的特征。虽然需要记忆具体定义，但选项直接给出了明确的特征描述（转变温度低于两种晶型的熔点），不需要复杂的分析或比较。在选择题型中属于概念理解和简单辨析的难度等级。", "convertible": true, "correct_option": "The polymorphic transformation temperature is lower than the melting points of both crystal forms", "choice_question": "The characteristic of reversible polymorphic transformation is:", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The polymorphic transformation temperature is lower than the melting points of both crystal forms", "B": "The transformation occurs instantaneously at a single well-defined temperature", "C": "The high-temperature phase always has higher density than the low-temperature phase", "D": "The transformation requires nucleation sites and proceeds via diffusion mechanism" }, "correct_answer": "A", "explanation": "The correct answer A describes the fundamental thermodynamic requirement for reversible polymorphic transformations where both phases must remain solid during the transition. Option B exploits cognitive bias by suggesting a sharp transition temperature, which is characteristic of first-order transitions but not necessarily true for all reversible polymorphic cases. Option C uses professional intuition trap by implying a universal density relationship, while in reality some materials (like water/ice) show inverse behavior. Option D is a multi-level verification trap describing irreversible martensitic transformations rather than reversible polymorphic changes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4042, "question": "How does increasing temperature affect the concentration of both electrons and holes in an intrinsic semiconductor?(a) Increases the concentration.(b) Decreases the concentration.(c) May increase and/or decrease the concentration, depending on the temperature range.", "answer": "Increasing temperature increases the concentration of both electrons and holes in an intrinsic semiconductor.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对温度如何影响本征半导体中电子和空穴浓度的基本原理的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆温度对半导体中电子和空穴浓度的影响这一基本原理。题目选项设计简单，正确选项直接对应基础知识点，无需复杂分析或概念区分。因此属于最简单的难度等级1。", "convertible": true, "correct_option": "(a) Increases the concentration.", "choice_question": "How does increasing temperature affect the concentration of both electrons and holes in an intrinsic semiconductor?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option that matches the provided answer. It can be directly used as a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases the concentration", "B": "Decreases the concentration due to enhanced lattice scattering", "C": "Remains constant as generation and recombination rates balance out", "D": "First increases then decreases after reaching a critical temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because in intrinsic semiconductors, increasing temperature provides more thermal energy to break covalent bonds, generating more electron-hole pairs. Option B exploits the common misconception that increased scattering reduces carrier concentration, while it actually affects mobility. Option C creates a false equilibrium scenario that doesn't apply to intrinsic materials. Option D mimics the behavior of extrinsic semiconductors but is misleading for intrinsic cases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2586, "question": "FCC crystal, pure bending occurs on the (110) plane around the [001] axis, what kind of dislocations will form (specify the direction of the dislocation line and the Burgers vector).", "answer": "Edge type, dislocation line direction=[001], Burgers vector=a[110]/2", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求详细解释和指定位错的方向和Burgers向量，答案需要文字描述和具体参数，而非选择或判断。 | 知识层次: 题目需要理解FCC晶体结构、纯弯曲变形机制、位错类型及其伯格斯矢量的确定，涉及多个概念的关联和综合分析。虽然不涉及复杂的计算，但需要对晶体学方向和位错性质有较深入的理解和应用能力。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目涉及FCC晶体结构、纯弯曲变形、滑移面和滑移方向等概念的综合理解。其次，需要正确识别(110)平面和[001]轴的关系，并推导出在此变形条件下会形成的位错类型。此外，题目要求具体说明位错线方向和Burgers矢量，这需要深入理解位错几何和晶体学方向的计算。虽然题目给出了正确选项，但解题过程需要多步概念关联和综合分析，包括：1)理解纯弯曲变形产生的位错类型；2)确定滑移面和滑移方向；3)计算Burgers矢量；4)判断位错线方向。这些步骤都超出了基础知识的简单回忆，需要进行较深入的分析和计算。", "convertible": true, "correct_option": "Edge type, dislocation line direction=[001], Burgers vector=a[110]/2", "choice_question": "FCC crystal, pure bending occurs on the (110) plane around the [001] axis, what kind of dislocations will form (specify the direction of the dislocation line and the Burgers vector)?", "conversion_reason": "The answer is a standard terminology and concept, which can be converted into a multiple-choice question format by providing the correct option as one of the choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Edge type, dislocation line direction=[001], Burgers vector=a[110]/2", "B": "Screw type, dislocation line direction=[110], Burgers vector=a[001]/2", "C": "Mixed type, dislocation line direction=[111], Burgers vector=a[110]/2", "D": "Edge type, dislocation line direction=[110], Burgers vector=a[001]" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC crystals under pure bending on (110) plane around [001] axis, edge dislocations with Burgers vector a[110]/2 are generated to accommodate the lattice curvature, with dislocation lines parallel to the bending axis [001]. Option B incorrectly suggests screw dislocations with wrong Burgers vector direction. Option C introduces an invalid mixed-type dislocation with incorrect line direction. Option D uses the correct dislocation type but wrong line direction and Burgers vector magnitude, exploiting common confusion between edge dislocation geometries.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2152, "question": "For a face-centered cubic crystal, the movable slip system is (111)[110]. If the slip is caused by a pure edge dislocation, indicate the direction of the dislocation line.", "answer": "The dislocation line lies on the slip plane (111). Let the direction of the dislocation line be [uow], then u+v-w=0; the dislocation line is perpendicular to b, i.e., perpendicular to [110], so -u+v=0. From the above two equations, u:v:w=1:1:2, thus the direction of the dislocation line is [112].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来确定位错线的方向，答案给出了详细的推导过程和结论，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目需要理解面心立方晶体的滑移系统，并应用几何关系推导位错线方向。涉及多步计算和概念关联，需要综合分析滑移面、位错线和柏氏矢量的几何关系。 | 难度: 在选择题型中，该题目属于较高难度。原因如下：", "convertible": true, "correct_option": "[112]", "choice_question": "For a face-centered cubic crystal with a movable slip system (111)[110], if the slip is caused by a pure edge dislocation, what is the direction of the dislocation line?", "conversion_reason": "The answer is a specific direction [112], which can be presented as a clear option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[110]", "B": "[112]", "C": "[111]", "D": "[100]" }, "correct_answer": "B", "explanation": "The correct answer is B [112] because for a pure edge dislocation in an FCC crystal with slip system (111)[110], the dislocation line must be perpendicular to the Burgers vector [110] and lie in the slip plane (111). The cross product of [110] and [111] gives [112]. Option A [110] is the Burgers vector direction, which is a common first-impression mistake. Option C [111] is the slip plane normal, exploiting confusion between line direction and plane orientation. Option D [100] is a high-symmetry direction that appears plausible but doesn't satisfy the geometric constraints.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3326, "question": "Explain the factors affecting hardenability.", "answer": "Hardenability mainly depends on the carbon content of martensite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释影响淬透性的因素，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目要求解释影响淬透性的因素，需要理解淬透性的基本原理，并能够关联多个影响因素（如碳含量、合金元素、冷却速率等）进行综合分析。虽然答案只提到马氏体的碳含量，但完整的回答需要更全面的分析和关联。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求解释影响淬透性的因素，而正确选项涉及马氏体碳含量这一关键概念，需要考生具备将材料性能与微观结构关联的能力。虽然不涉及多步计算，但需要对淬透性机制有综合理解，这超过了基础记忆层面，属于概念关联和中等应用层次。", "convertible": true, "correct_option": "Hardenability mainly depends on the carbon content of martensite.", "choice_question": "Which of the following factors mainly affects hardenability?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The carbon content of martensite", "B": "The cooling rate during quenching", "C": "The dislocation density in austenite prior to transformation", "D": "The grain size of the parent austenite phase" }, "correct_answer": "A", "explanation": "The correct answer is A because hardenability fundamentally depends on the ability to form martensite, which is primarily determined by its carbon content. Option B is a strong distractor as it exploits the common confusion between hardenability (potential to harden) and hardness (actual result). Option C targets advanced AI by introducing a real metallurgical factor (dislocations) that affects other properties but not hardenability. Option D uses the grain size fallacy - while it influences mechanical properties, it doesn't directly control hardenability.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3908, "question": "If the atomic radius of a metal that has the body-centered cubic crystal structure is 0.181nm, calculate the volume of its unit cell.", "answer": "the volume of the unit cell is 0.0271 nm^3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解单位晶胞的体积，答案是一个具体的数值结果。 | 知识层次: 题目考查基本公式应用和简单计算，直接套用体心立方晶胞体积的计算公式即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算体心立方晶体结构的单位晶胞体积，只需应用已知的原子半径和体心立方晶体的几何关系公式（V = (4r/√3)^3）进行简单计算即可得出答案。无需多个公式组合或复杂推导，属于基础级别的应用。", "convertible": true, "correct_option": "0.0271 nm^3", "choice_question": "If the atomic radius of a metal that has the body-centered cubic crystal structure is 0.181nm, what is the volume of its unit cell?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0271 nm^3", "B": "0.0382 nm^3", "C": "0.0123 nm^3", "D": "0.0486 nm^3" }, "correct_answer": "A", "explanation": "For a body-centered cubic (BCC) structure, the relationship between the atomic radius (r) and the unit cell edge length (a) is a = 4r/√3. Given r = 0.181 nm, a = 0.416 nm. The volume of the unit cell is a^3 = 0.0271 nm^3. Option B incorrectly uses the face-centered cubic (FCC) relationship (a = 4r/√2). Option C is the volume of just the atoms in the unit cell (2 atoms × (4/3)πr^3). Option D incorrectly calculates using a = 2r.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 515, "question": "In face-centered cubic metals, can the dislocation b3 generated by the dislocation reaction b1 + b2 = b3 move on the slip plane?", "answer": "The slip plane of face-centered cubic metals is {111}, and b3 is perpendicular to this crystal plane, so it cannot slip.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目需要解释和论述为什么位错b3不能在滑移面上移动，答案提供了详细的晶体学分析和文字解释，符合简答题的特征。 | 知识层次: 题目涉及面心立方金属中位错反应生成的位错b3在滑移面上的运动能力，需要综合运用位错理论、晶体学知识以及滑移机制进行推理分析。解答不仅需要理解位错反应的基本原理，还需要分析位错b3与滑移面{111}的几何关系，判断其是否能够滑移。这属于对多个概念的深度理解和综合应用，思维过程较为复杂。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "No, because b3 is perpendicular to the {111} slip plane and cannot slip.", "choice_question": "In face-centered cubic metals, can the dislocation b3 generated by the dislocation reaction b1 + b2 = b3 move on the slip plane?", "conversion_reason": "The answer is a clear and concise explanation that can be directly used as a correct option in a multiple-choice question. The question itself is already in a format that can be easily converted to a multiple-choice question by adding plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because b3 has the minimum energy configuration for slip", "B": "No, because b3 is perpendicular to the {111} slip plane and cannot slip", "C": "Yes, but only at temperatures above 0.6Tm due to thermal activation", "D": "No, because b3 is a sessile dislocation with Burgers vector parallel to the slip plane" }, "correct_answer": "B", "explanation": "The correct answer is B because in FCC metals, the dislocation b3 formed by the reaction b1 + b2 = b3 has a Burgers vector perpendicular to the {111} slip plane, making it immobile. Option A exploits the common misconception that minimum energy configurations always enable slip. Option C uses a plausible-sounding temperature condition to mislead. Option D incorrectly describes the Burgers vector orientation while using the correct 'sessile' terminology.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2723, "question": "Assume there is an edge dislocation with Burgers vector b in the [0-10] direction gliding along the (100) plane. If another edge dislocation with Burgers vector in the [010] direction moves through the (001) plane, will this dislocation form a kink or a jog when passing through the aforementioned dislocation?", "answer": "Kink", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从两个选项（kink或jog）中选择正确答案 | 知识层次: 题目需要理解位错的基本概念（如Burgers向量和滑移面），并能够分析两种不同位错相互作用时的行为。这涉及到多个概念的关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题型中，这道题目属于较高难度，需要考生综合运用位错理论中的多个概念（Burgers矢量、滑移面、割阶与扭折的形成机制）并进行空间几何关系的判断。具体来说：", "convertible": true, "correct_option": "Kink", "choice_question": "Assume there is an edge dislocation with Burgers vector b in the [0-10] direction gliding along the (100) plane. If another edge dislocation with Burgers vector in the [010] direction moves through the (001) plane, will this dislocation form a kink or a jog when passing through the aforementioned dislocation?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer (Kink). It can be directly converted to a single-choice question by presenting the options (Kink or Jog) and marking 'Kink' as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Kink", "B": "Jog", "C": "Both kink and jog", "D": "Neither, they will annihilate each other" }, "correct_answer": "A", "explanation": "The correct answer is A (Kink) because when two edge dislocations with perpendicular Burgers vectors intersect, the moving dislocation will form a kink (a segment lying in a different slip plane) rather than a jog (a segment out of the slip plane). Option B is a common mistake due to confusing the geometric configurations of kinks and jogs. Option C exploits the tendency to overcomplicate the analysis by suggesting both occur. Option D is a cognitive trap based on misapplying the concept of dislocation annihilation to this specific geometric configuration.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4169, "question": "Mole, in the context of this book, is taken in units of gram-mole. On this basis, how many atoms are there in a pound-mole of a substance?", "answer": "2.73 x 10^26 atoms/lb-mol", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定一磅摩尔物质中的原子数量。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目考查基本单位换算和简单公式应用（阿伏伽德罗常数的直接应用），仅需一步计算即可得出结果，属于基础概念的直接应用。 | 难度: 在选择题型中，该题目仅需要直接应用基本公式（阿伏伽德罗常数）进行简单的单位转换计算，属于单一公式直接计算的类型。解题步骤简单明了，无需复杂的推理或多步骤计算，因此在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "2.73 x 10^26 atoms/lb-mol", "choice_question": "Mole, in the context of this book, is taken in units of gram-mole. On this basis, how many atoms are there in a pound-mole of a substance?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.73 x 10^26 atoms/lb-mol", "B": "6.022 x 10^23 atoms/lb-mol", "C": "453.6 x 10^23 atoms/lb-mol", "D": "1.66 x 10^24 atoms/lb-mol" }, "correct_answer": "A", "explanation": "The correct answer is A because a pound-mole is defined as the number of atoms in 453.592 grams (1 pound) of a substance. Since 1 gram-mole contains Avogadro's number of atoms (6.022 x 10^23), scaling this to a pound gives 453.592 x 6.022 x 10^23 ≈ 2.73 x 10^26 atoms/lb-mol. Option B is a cognitive bias trap using the raw Avogadro's number without pound conversion. Option C is a unit confusion trap multiplying pound-to-gram conversion factor incorrectly. Option D is a professional intuition trap based on approximate kilogram-to-pound ratio miscalculation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4904, "question": "For the brass and titanium pair that are coupled in seawater, predict the possibility of corrosion; if corrosion is probable, note which metal/alloy will corrode.", "answer": "For the brass-titanium pair, corrosion is possible, and brass will corrode.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求预测腐蚀可能性并指出哪个金属会腐蚀，需要文字解释和论述，答案也是以文字形式给出解释。 | 知识层次: 题目要求预测腐蚀可能性并确定腐蚀金属，需要理解电偶腐蚀的基本原理（不同金属的电化学电位差异），并应用这些知识进行综合分析。虽然不涉及复杂计算，但需要关联多个概念（如金属的活性、环境因素等）进行判断，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解电偶腐蚀的基本原理，并能识别不同金属在特定环境（海水）下的电化学行为。题目要求考生将金属的电偶序知识应用到具体配对（黄铜-钛）中，并判断腐蚀倾向和优先腐蚀的金属。这需要考生掌握中等应用层次的知识，包括多步概念关联和综合分析能力，但不需要进行复杂的多角度或深度关联性分析。", "convertible": true, "correct_option": "For the brass-titanium pair, corrosion is possible, and brass will corrode.", "choice_question": "For the brass and titanium pair that are coupled in seawater, predict the possibility of corrosion; if corrosion is probable, note which metal/alloy will corrode.", "conversion_reason": "The answer is a standard and concise statement that can be directly used as a correct option in a multiple-choice question. The question can be presented as is, with the answer serving as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Corrosion is possible, and titanium will corrode", "B": "No corrosion will occur due to titanium's passivation layer", "C": "Corrosion is possible, and brass will corrode", "D": "Both metals will corrode equally due to galvanic coupling" }, "correct_answer": "C", "explanation": "The correct answer is C because in the brass-titanium pair in seawater, brass (anodic) will corrode while titanium (cathodic) remains protected due to its higher nobility. Option A is a cognitive bias trap that reverses the galvanic series relationship. Option B exploits the common knowledge of titanium's passivation but ignores the galvanic coupling effect. Option D creates a false symmetry by suggesting equal corrosion, which violates fundamental electrochemical principles.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 386, "question": "From a diffusion perspective, the mobility of low-angle grain boundaries is lower compared to that of high-angle grain boundaries.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（低角度晶界的迁移率低于高角度晶界），并要求判断其正确性（√表示正确），这符合判断题的特征。 | 知识层次: 题目考查的是关于晶界扩散特性的基本概念记忆，即低角度晶界和高角度晶界在扩散过程中的迁移率差异。这属于对材料科学中晶界行为的基础知识的理解和记忆，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅涉及低角度晶界和高角度晶界迁移性的比较，属于基础概念记忆层次，无需复杂分析或推理。学生只需记住相关定义即可直接判断正误，因此难度最低。", "convertible": true, "correct_option": "√", "choice_question": "From a diffusion perspective, the mobility of low-angle grain boundaries is lower compared to that of high-angle grain boundaries.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All high-angle grain boundaries exhibit higher mobility than low-angle grain boundaries under any temperature condition.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While generally true that high-angle grain boundaries have higher mobility, this is not absolute. At very high temperatures, some low-angle boundaries may show comparable or even higher mobility due to thermal activation effects. The statement's use of 'any temperature condition' makes it incorrect. Additionally, certain special grain boundary configurations (like coincident site lattice boundaries) may exhibit anomalously low mobility despite being high-angle boundaries.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1705, "question": "Explain the commonly used diffusion mechanisms.", "answer": "The commonly used diffusion mechanisms are the vacancy mechanism and the interstitial mechanism.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释常见的扩散机制，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查扩散机制的基本分类和定义，属于基础概念的记忆和理解 | 难度: 在选择题型中，该题目仅要求考生记忆并识别常见的扩散机制名称（空位机制和间隙机制），属于最基础的定义简答层次。题目不涉及概念解释或复杂体系阐述，仅需简单回忆即可作答，因此属于等级1难度。", "convertible": true, "correct_option": "The commonly used diffusion mechanisms are the vacancy mechanism and the interstitial mechanism.", "choice_question": "Which of the following describes the commonly used diffusion mechanisms?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Vacancy mechanism and interstitial mechanism", "B": "Grain boundary diffusion and surface diffusion", "C": "Dislocation pipe diffusion and vacancy mechanism", "D": "Interstitialcy mechanism and substitutional diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because vacancy and interstitial mechanisms are the two fundamental atomic-scale diffusion mechanisms in crystalline materials. Option B lists real diffusion pathways but these are faster secondary mechanisms, not the primary atomic mechanisms. Option C combines a real mechanism (vacancy) with a specialized case (dislocation pipe). Option D uses the rarely mentioned interstitialcy mechanism and the incorrect term 'substitutional diffusion' to create confusion with substitutional alloys.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3070, "question": "What is reaction sintering?", "answer": "Reaction sintering is a process in which ceramic powders of various compounds (such as Si, Si-SiN4 powder, etc.) are pressed into shape and then subjected to special chemical treatment during sintering to obtain ceramics.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"reaction sintering\"进行文字解释和论述，答案提供了详细的定义和过程描述，符合简答题的特征。 | 知识层次: 题目考查对反应烧结（reaction sintering）这一基本概念的定义和简单描述，属于基础概念的记忆和理解层次，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。虽然题目要求考生理解反应烧结的定义和基本原理，但不需要进行复杂的概念体系阐述或比较分析。正确选项提供了明确的定义和基本过程描述，属于中等难度的选择题。", "convertible": true, "correct_option": "Reaction sintering is a process in which ceramic powders of various compounds (such as Si, Si-SiN4 powder, etc.) are pressed into shape and then subjected to special chemical treatment during sintering to obtain ceramics.", "choice_question": "Which of the following best describes reaction sintering?", "conversion_reason": "The answer is a standard definition of a technical term, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Reaction sintering is a process in which ceramic powders of various compounds are pressed into shape and then subjected to special chemical treatment during sintering to obtain ceramics.", "B": "Reaction sintering involves the simultaneous compaction and chemical reaction of powder mixtures to form a dense ceramic without external pressure.", "C": "Reaction sintering refers to the sintering process where pre-reacted ceramic powders are consolidated without any further chemical changes.", "D": "Reaction sintering is a technique where ceramic powders are sintered under reactive gas atmospheres to prevent oxidation during densification." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes reaction sintering as involving both shaping and special chemical treatment during sintering. Option B is incorrect because it omits the crucial aspect of chemical treatment during sintering. Option C is wrong as it describes conventional sintering of pre-reacted powders. Option D is a misleading description of protective atmosphere sintering, not reaction sintering. The key challenge is recognizing that reaction sintering specifically requires chemical transformation during the sintering process.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3735, "question": "What are the maximum stress, the minimum stress, and the mean stress on the part during its use under conditions that provide for equal compressive and tensile stresses?", "answer": "The maximum stress is +22 mpa, the minimum stress is -22 mpa, and the mean stress is 0 mpa.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释最大应力、最小应力和平均应力的具体数值，答案以文字形式给出具体数值，属于简答题类型。 | 知识层次: 题目涉及基本应力概念的应用，要求计算最大应力、最小应力和平均应力，属于直接套用基本公式和简单计算的范畴，不需要复杂的分析或综合思维。 | 难度: 在选择题中属于简单难度，题目直接给出了应力条件（等值压缩和拉伸应力），只需要应用基本公式计算最大、最小和平均应力。解题步骤简单，仅需套用公式即可得出答案，无需复杂分析或深入理解多个概念。", "convertible": true, "correct_option": "The maximum stress is +22 mpa, the minimum stress is -22 mpa, and the mean stress is 0 mpa.", "choice_question": "What are the maximum stress, the minimum stress, and the mean stress on the part during its use under conditions that provide for equal compressive and tensile stresses?", "conversion_reason": "The answer is a specific and standardized response, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The maximum stress is +22 MPa, the minimum stress is -22 MPa, and the mean stress is 0 MPa", "B": "The maximum stress is +22 MPa, the minimum stress is -18 MPa, and the mean stress is +2 MPa", "C": "The maximum stress is +20 MPa, the minimum stress is -20 MPa, and the mean stress is 0 MPa", "D": "The maximum stress is +22 MPa, the minimum stress is -22 MPa, and the mean stress is +2 MPa" }, "correct_answer": "A", "explanation": "The correct answer is A because the conditions specify equal compressive and tensile stresses, which means the magnitudes must be identical (+22 MPa and -22 MPa) and the mean stress must be zero. Option B introduces unequal magnitudes and a non-zero mean, exploiting the cognitive bias that small asymmetries might exist. Option C uses equal magnitudes but wrong values, playing on the expectation of round numbers. Option D maintains correct magnitudes but incorrectly calculates mean stress, targeting confusion between stress range and mean stress calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4143, "question": "Which type(s) of magnetic materials may be classified as either soft or hard?(a) Diamagnetic(b) Paramagnetic(c) Ferromagnetic(d) Antiferromagnetic(e) Ferrimagnetic", "answer": "Ferromagnetic and ferrimagnetic materials may be classified as either soft or hard.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，答案明确指出了正确选项 | 知识层次: 题目考查对磁性材料分类的基础概念记忆，只需要理解并区分不同类型的磁性材料是否可以被分类为软磁或硬磁，不需要复杂的分析或计算。 | 难度: 在选择题中属于中等偏下难度，需要理解磁性材料的基本分类（软磁和硬磁）并能够区分哪些类型（铁磁和亚铁磁）可以进一步细分为这两类。虽然涉及多个概念，但主要是基础概念的记忆和简单辨析，不需要复杂的分析或深度理解。", "convertible": true, "correct_option": "(c) Ferromagnetic and (e) Ferrimagnetic", "choice_question": "Which type(s) of magnetic materials may be classified as either soft or hard?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer specifies which options are correct. It can be converted to a single-choice question by selecting the correct combination of options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(c) Ferromagnetic and (e) Ferrimagnetic", "B": "选项B", "C": "选项D", "D": "选项C" }, "correct_answer": "A", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 2014, "question": "The density of ZnS is $4.1~\\\\mathrm{Mg}/\\\\mathrm{m}^{3}$, calculate the distance between the centers of the two ions based on this", "answer": "The distance between the centers of the two ions is $0.234\\\\mathrm{~n}\\\\mathrm{m}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求基于给定的密度数据进行计算，得出两个离子中心之间的距离。答案是一个具体的数值结果（0.234 nm），这表明需要通过公式和数值计算来解决问题，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括密度与晶格参数的关系推导，以及离子间距的计算，涉及概念关联和综合分析。虽然不涉及复杂的推理分析或机理解释，但比简单的公式应用要求更高。 | 难度: 在选择题中属于中等偏上难度，需要综合运用密度计算、晶体结构知识和单位换算等多步骤计算过程。题目要求考生根据密度数据反推离子间距，涉及对ZnS晶体结构的理解（如闪锌矿结构）、阿伏伽德罗常数的应用以及立方晶系几何关系的推导。虽然选择题提供了正确选项可以部分降低难度，但仍需要考生具备较强的综合分析能力和计算技巧，属于需要多概念关联的综合性计算问题。", "convertible": true, "correct_option": "0.234 nm", "choice_question": "The density of ZnS is $4.1~\\mathrm{Mg}/\\mathrm{m}^{3}$. What is the distance between the centers of the two ions based on this?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.234 nm", "B": "0.283 nm", "C": "0.197 nm", "D": "0.312 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.234 nm) which is calculated using the zinc blende structure of ZnS with 4 formula units per unit cell. Option B (0.283 nm) is the distance in wurtzite structure ZnS, exploiting structural polymorphism confusion. Option C (0.197 nm) is the sum of ionic radii without considering proper packing, appealing to oversimplified intuition. Option D (0.312 nm) is the distance if calculated for rock salt structure, using an incorrect but common crystal structure assumption.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 555, "question": "7.During martensitic transformation, the new phase often begins to form on a specific crystallographic plane of the parent phase, which is called (20).", "answer": "(20) habit plane", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（habit plane）作为答案，属于需要简短文字回答的题目类型 | 知识层次: 题目考查马氏体相变中基本概念\"惯习面\"的记忆和理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即马氏体相变中特定晶面的名称（habit plane）。题目直接给出定义性知识，无需解释或复杂分析，属于最基本难度的选择题。", "convertible": true, "correct_option": "habit plane", "choice_question": "During martensitic transformation, the new phase often begins to form on a specific crystallographic plane of the parent phase, which is called:", "conversion_reason": "The answer is a standard term (habit plane), making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "habit plane", "B": "slip plane", "C": "twin boundary", "D": "Bain distortion axis" }, "correct_answer": "A", "explanation": "The correct answer is A (habit plane) because it specifically refers to the crystallographic plane where martensite formation initiates. Option B (slip plane) exploits the cognitive bias of associating phase transformations with dislocation motion. Option C (twin boundary) is a professional intuition trap, as twins are common in martensite but not the initiation site. Option D (Bain distortion axis) is a multi-level verification trap, referencing a related but distinct concept in martensitic transformations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4370, "question": "Briefly explain why there is no bainite transformation region on the continuous cooling transformation diagram for an iron-carbon alloy of eutectoid composition.", "answer": "There is no bainite transformation region on the continuous cooling transformation diagram for an ironcarbon alloy of eutectoid composition because by the time a cooling curve has passed into the bainite region, the entirety of the alloy specimen will have transformed to pearlite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释为什么在共析成分的铁碳合金的连续冷却转变图中没有贝氏体转变区，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释为什么在共析成分的铁碳合金连续冷却转变图中没有贝氏体转变区，这需要综合运用相变动力学、冷却速率对组织转变的影响等知识，进行推理分析。不仅需要理解珠光体和贝氏体形成的条件，还需要分析连续冷却过程中不同冷却速率下组织转变的竞争关系，思维过程较为深入。 | 难度: 在选择题型中属于最高难度等级，因为该题目要求考生不仅理解连续冷却转变图的基本概念，还需要深入掌握珠光体和贝氏体转变的动力学原理。正确选项涉及对冷却曲线与相变区域关系的复杂分析，需要综合运用相变动力学知识进行推理判断。这种题目在选择题中属于需要全面分析复杂现象的题型，远超简单记忆或基础理解的要求。", "convertible": true, "correct_option": "There is no bainite transformation region on the continuous cooling transformation diagram for an iron-carbon alloy of eutectoid composition because by the time a cooling curve has passed into the bainite region, the entirety of the alloy specimen will have transformed to pearlite.", "choice_question": "Why is there no bainite transformation region on the continuous cooling transformation diagram for an iron-carbon alloy of eutectoid composition?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The cooling rate required for bainite formation is always slower than the critical rate for pearlite suppression in eutectoid alloys", "B": "Bainite formation requires carbon diffusion distances that cannot be achieved during continuous cooling of eutectoid compositions", "C": "The austenite-to-bainite transformation is thermodynamically forbidden at eutectoid composition", "D": "The bainite start temperature coincides with the pearlite finish temperature in eutectoid steels" }, "correct_answer": "D", "explanation": "The correct answer is D because the bainite transformation is kinetically suppressed in eutectoid alloys where pearlite formation completes before reaching bainite formation temperatures. Option A is incorrect because some bainite cooling rates are actually faster than pearlite formation rates. Option B exploits diffusion misconception but bainite can form with short-range diffusion. Option C uses thermodynamic impossibility which is false as bainite is metastable but possible. Option D correctly identifies the overlapping transformation ranges that prevent bainite formation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 913, "question": "What is the difference in nucleation sites between recrystallization and solidification processes?", "answer": "Solidification is often homogeneous nucleation; recrystallization nucleation occurs in existing deformation inhomogeneous regions, such as near grain boundaries, shear bands, deformation bands, and around second-phase particles.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述再结晶和凝固过程中成核位点的差异，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目要求比较两种不同过程（再结晶和凝固）的形核位点差异，涉及对形核机制的理解和概念关联，需要综合分析不同条件下的形核行为，属于中等应用层次。 | 难度: 在选择题中属于较高难度，题目要求考生不仅理解再结晶和凝固两种过程的成核机制，还需要能够比较和分析它们之间的差异。正确选项涉及多个专业概念（如均匀成核、非均匀成核、晶界、剪切带等）的综合运用，并需要将这些概念与具体的材料加工过程联系起来。这种多角度分析和概念关联的要求使得该题目在选择题型中具有较高的难度。", "convertible": true, "correct_option": "Solidification is often homogeneous nucleation; recrystallization nucleation occurs in existing deformation inhomogeneous regions, such as near grain boundaries, shear bands, deformation bands, and around second-phase particles.", "choice_question": "What is the difference in nucleation sites between recrystallization and solidification processes?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solidification nucleation occurs at high-energy interfaces, while recrystallization nucleation requires pre-existing lattice defects", "B": "Both processes initiate at grain boundaries, but recrystallization additionally requires dislocations", "C": "Solidification is homogeneous nucleation, while recrystallization occurs at deformation-induced inhomogeneities", "D": "Recrystallization requires second-phase particles, while solidification occurs at any free surface" }, "correct_answer": "C", "explanation": "The correct answer C precisely distinguishes the fundamental difference: solidification typically begins with homogeneous nucleation in the melt, while recrystallization nucleation is inherently heterogeneous, occurring preferentially at deformation-induced features. Option A is misleading by suggesting high-energy interfaces for solidification, which is only true for some cases. Option B incorrectly equates the nucleation sites for both processes. Option D over-specifies the requirement for recrystallization while under-specifying solidification conditions. These distractors exploit common misconceptions about nucleation mechanisms in phase transformations versus microstructure evolution processes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 613, "question": "From what is Fe3CI precipitated", "answer": "Liquid phase", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释Fe3CI的沉淀来源，答案是一个简短的文字描述而非选择、判断或计算 | 知识层次: 题目考查Fe3CI沉淀来源的基础概念记忆，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即Fe3CI的沉淀来源。正确选项\"Liquid phase\"是一个简单的定义性知识，不需要复杂的解释或分析。题目仅测试学生对这一基本事实的记忆，属于最基础的选择题难度等级。", "convertible": true, "correct_option": "Liquid phase", "choice_question": "From what is Fe3CI precipitated?", "conversion_reason": "The answer is a standard term that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Liquid phase", "B": "Solid-state reaction", "C": "Vapor deposition", "D": "Electrochemical reduction" }, "correct_answer": "A", "explanation": "Fe3Cl is precipitated from the liquid phase due to its solubility characteristics. Option B exploits the common misconception that intermetallic compounds form primarily through solid-state reactions. Option C targets the AI's tendency to associate unusual compounds with vapor deposition techniques. Option D leverages the material science intuition that electrochemical methods are widely used for compound synthesis, creating a plausible but incorrect association.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1956, "question": "For cases where the concentration gradient changes over time, can the first law of diffusion be applied?", "answer": "The first law of diffusion can also be applied to non-steady-state diffusion, but it must be modified.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对非稳态扩散情况下第一扩散定律的应用进行解释和论述，答案提供了文字解释而非选择、判断或计算。 | 知识层次: 题目涉及非稳态扩散情况下第一扩散定律的应用，需要对扩散定律的基本原理有理解，并能进行概念关联和综合分析，以判断其适用性和必要的修改。这超出了简单记忆或直接套用的层次，但尚未达到复杂分析或高级综合的深度。 | 难度: 在选择题中属于中等难度，需要理解非稳态扩散的概念，并能将其与第一扩散定律的应用条件联系起来进行分析。题目要求考生不仅知道第一扩散定律的基本应用，还要理解其在变化条件下的适用性及必要的修正，涉及概念关联和综合分析能力。", "convertible": true, "correct_option": "The first law of diffusion can also be applied to non-steady-state diffusion, but it must be modified.", "choice_question": "For cases where the concentration gradient changes over time, which of the following statements about the first law of diffusion is correct?", "conversion_reason": "The original short answer question has a clear and concise answer that can be used as the correct option in a multiple-choice format. The question can be rephrased to fit the multiple-choice format by asking for the correct statement among possible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The first law of diffusion can also be applied to non-steady-state diffusion, but it must be modified.", "B": "The first law of diffusion is strictly only applicable to steady-state diffusion conditions.", "C": "The first law remains unchanged but requires using instantaneous concentration gradient values.", "D": "The first law becomes invalid and must be replaced with the second law of diffusion." }, "correct_answer": "A", "explanation": "The correct answer is A because Fick's first law can be adapted for non-steady-state diffusion by using a time-dependent form, though this is less common than using Fick's second law. Option B exploits the common misconception that the first law is strictly for steady-state. Option C sounds plausible by suggesting using instantaneous gradients, but incorrectly implies no modification is needed. Option D creates a false dichotomy by suggesting complete replacement rather than adaptation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3762, "question": "Calculate the diameter of the cylindrical riser required to prevent shrinkage in a 1 in. x 6 in. x 6 in. casting if the H/D of the riser is 1.0.", "answer": "the diameter of the riser must be at least 2.25 in.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定圆柱形冒口的直径，答案是一个具体的数值（2.25 in.），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括理解铸造收缩原理、应用H/D比例关系以及计算圆柱形冒口的直径，涉及概念关联和综合分析。虽然不涉及复杂的推理或创新设计，但需要一定的计算步骤和概念理解。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求计算圆柱形冒口的直径以防止收缩，涉及多步计算和概念关联（如H/D比、冒口尺寸与铸件尺寸的关系）。虽然题目提供了具体参数和正确选项，但解题过程需要综合运用材料科学和铸造工艺知识，属于中等应用层次的问题。", "convertible": true, "correct_option": "the diameter of the riser must be at least 2.25 in.", "choice_question": "What is the diameter of the cylindrical riser required to prevent shrinkage in a 1 in. x 6 in. x 6 in. casting if the H/D of the riser is 1.0?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.25 in", "B": "1.5 in", "C": "3.0 in", "D": "4.5 in" }, "correct_answer": "A", "explanation": "The correct diameter of 2.25 in is calculated using the modulus method considering the casting's volume-to-surface area ratio. Option B (1.5 in) is a common error from misapplying the Chvorinov's rule without proper scaling. Option C (3.0 in) results from incorrectly doubling the minimum dimension. Option D (4.5 in) comes from overestimating the required safety factor for this alloy system.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 199, "question": "Heat treat Si3N4 at the eutectic temperature and measure its thermal etching groove angle as 60°, calculate the grain boundary energy of Si3N4.", "answer": "γss=2γsvcos(ψ/2)=2×900cos30°=1558.8mN/m", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解Si3N4的晶界能，答案给出了具体的计算过程和结果。 | 知识层次: 题目需要应用公式进行计算，涉及多步推理和概念关联（如热蚀刻沟槽角与晶界能量的关系），但不需要复杂的综合分析或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解热处理的背景知识、热蚀刻沟角的概念，并正确应用公式γss=2γsvcos(ψ/2)进行多步计算。虽然题目给出了关键参数（ψ=60°和γsv=900），但需要考生能够正确关联这些概念并执行三角函数计算（cos30°），最终得出精确的晶界能量值。这超出了简单记忆或单步计算的要求，属于需要概念关联和综合分析的题目。", "convertible": true, "correct_option": "1558.8mN/m", "choice_question": "Heat treat Si3N4 at the eutectic temperature and measure its thermal etching groove angle as 60°, the grain boundary energy of Si3N4 is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice in a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1558.8 mN/m", "B": "779.4 mN/m", "C": "3117.6 mN/m", "D": "1039.2 mN/m" }, "correct_answer": "A", "explanation": "The correct answer is A (1558.8 mN/m) because it is derived from the Young-Laplace equation for thermal groove angles, using the correct surface energy value for Si3N4 at eutectic temperature. Option B (779.4 mN/m) is a common mistake where the angle is incorrectly halved. Option C (3117.6 mN/m) results from doubling the correct value, a frequent error when misapplying the angle-energy relationship. Option D (1039.2 mN/m) exploits confusion between grain boundary energy and surface energy values for similar ceramics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3734, "question": "To survive for one million cycles under conditions that provide for equal compressive and tensile stresses, what is the fatigue strength, or maximum stress amplitude, required?", "answer": "The fatigue strength at one million cycles is 22 mpa.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释在特定条件下所需的疲劳强度，答案提供了具体的数值和解释，符合简答题的特征。 | 知识层次: 题目要求根据给定的条件（一百万次循环）确定疲劳强度，这涉及直接应用疲劳强度的基本概念和已知数据（22 MPa）。虽然需要理解疲劳强度的定义，但主要是一个简单的数据应用过程，不需要多步计算或深入分析。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接套用基本公式或已知数据（疲劳强度在100万次循环下的标准值）即可得出正确答案。题目没有复杂的计算步骤或需要深入理解多个概念，仅需识别并选择给定的正确选项。因此，在选择题型内属于较低难度（等级2）。", "convertible": true, "correct_option": "22 mpa", "choice_question": "To survive for one million cycles under conditions that provide for equal compressive and tensile stresses, what is the fatigue strength, or maximum stress amplitude, required?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "22 MPa", "B": "44 MPa", "C": "110 MPa", "D": "220 MPa" }, "correct_answer": "A", "explanation": "The correct answer is 22 MPa, which represents the typical endurance limit for many steels under symmetric loading (R=-1). Option B (44 MPa) exploits the common mistake of doubling the correct value due to misinterpreting stress amplitude vs. range. Option C (110 MPa) uses a plausible value from high-cycle fatigue data but for different materials. Option D (220 MPa) represents a typical tensile strength value, creating confusion between static and fatigue properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1489, "question": "Which hazardous substances are prohibited by the EU RoHS Directive (now enacted as a regulation) that came into effect on July 1, 2006? What are their maximum allowable concentrations?", "answer": "Prohibited substances include lead (Pb, 0.1%), mercury (Hg, 0.1%), cadmium (Cd, 0.01%), hexavalent chromium (Cr+6, 0.1%), polybrominated biphenyls (PPB, 0.1%), and polybrominated diphenyl ethers (PBDE, 0.1%).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列出欧盟RoHS指令禁止的有害物质及其最大允许浓度，需要文字解释和论述，而不是从选项中选择或判断对错。答案提供了详细的物质名称和浓度限制，符合简答题的特征。 | 知识层次: 题目考查对欧盟RoHS指令中禁止的有害物质及其最大允许浓度的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目要求记忆欧盟RoHS指令中禁止的有害物质及其最大允许浓度，这属于基础概念记忆的范畴。正确选项直接列出了具体的物质和对应的浓度限制，没有涉及复杂的概念解释或体系阐述。因此，该题目在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "Prohibited substances include lead (Pb, 0.1%), mercury (Hg, 0.1%), cadmium (Cd, 0.01%), hexavalent chromium (Cr+6, 0.1%), polybrominated biphenyls (PPB, 0.1%), and polybrominated diphenyl ethers (PBDE, 0.1%).", "choice_question": "Which of the following lists the hazardous substances prohibited by the EU RoHS Directive (now enacted as a regulation) that came into effect on July 1, 2006, along with their maximum allowable concentrations?", "conversion_reason": "The answer is a standard list of substances and their concentrations, which can be presented as a correct option among other incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Lead (Pb, 0.1%), Mercury (Hg, 0.1%), Cadmium (Cd, 0.01%), Hexavalent Chromium (Cr+6, 0.1%), Polybrominated Biphenyls (PBB, 0.1%), Polybrominated Diphenyl Ethers (PBDE, 0.1%)", "B": "Lead (Pb, 0.1%), Mercury (Hg, 0.01%), Cadmium (Cd, 0.1%), Hexavalent Chromium (Cr+6, 0.1%), Polybrominated Biphenyls (PBB, 0.1%), Polybrominated Diphenyl Ethers (PBDE, 0.1%)", "C": "Lead (Pb, 0.1%), Mercury (Hg, 0.1%), Cadmium (Cd, 0.01%), Hexavalent Chromium (Cr+6, 0.1%), Polybrominated Biphenyls (PBB, 0.01%), Polybrominated Diphenyl Ethers (PBDE, 0.1%)", "D": "Lead (Pb, 0.1%), Mercury (Hg, 0.1%), Cadmium (Cd, 0.01%), Hexavalent Chromium (Cr+6, 0.01%), Polybrominated Biphenyls (PBB, 0.1%), Polybrominated Diphenyl Ethers (PBDE, 0.1%)" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately lists all substances prohibited by the RoHS Directive with their correct maximum allowable concentrations. Option B swaps the concentrations for Mercury and Cadmium, exploiting the common confusion between these two heavy metals. Option C incorrectly reduces the PBB limit to 0.01%, targeting memory recall errors about brominated compounds. Option D changes the Hexavalent Chromium limit to 0.01%, playing on the fact that chromium exists in multiple oxidation states with different regulations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4810, "question": "Give the approximate temperature at which creep deformation becomes an important consideration for gold.", "answer": "for au, 262°c or 504°f.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从选项中选择或判断对错，也不需要复杂的计算过程。答案是一个具体的数值，属于简答题类型。 | 知识层次: 题目考查对金属蠕变温度这一基础概念的记忆，只需直接回忆黄金的蠕变起始温度即可，不涉及复杂计算或分析过程。 | 难度: 在选择题型中，该题目仅要求记忆黄金的蠕变变形温度这一具体数值，属于基础概念记忆的简单问题。不需要解释或分析，只需直接回忆知识点即可作答。", "convertible": true, "correct_option": "262°C or 504°F", "choice_question": "At what approximate temperature does creep deformation become an important consideration for gold?", "conversion_reason": "The answer is a specific temperature range, which can be presented as a correct option among other plausible but incorrect temperature ranges.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "262°C (504°F)", "B": "1063°C (melting point)", "C": "150°C (typical recrystallization temperature)", "D": "400°C (common threshold for FCC metals)" }, "correct_answer": "A", "explanation": "The correct answer is A because creep becomes significant at approximately 0.3-0.4 of the absolute melting temperature (1337K), which for gold is around 262°C. Option B exploits the cognitive bias of associating creep with melting point. Option C uses recrystallization temperature which is irrelevant to creep. Option D creates a false analogy with general FCC metal behavior while ignoring gold's specific properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1624, "question": "The formation of nuclei in a homogeneous liquid phase through conditions such as structural fluctuations and energy fluctuations is called (10) nucleation", "answer": "(10) homogeneous", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（homogeneous nucleation）来完成句子，属于需要简短文字回答的题目类型，而不是从多个选项中选择或判断对错。 | 知识层次: 题目考查基本概念的记忆和理解，即均相成核的定义和分类，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接考察对\"homogeneous nucleation\"这一基础概念的记忆，无需解释或复杂推理。正确选项是术语本身，只需识别并匹配定义即可完成选择，属于最基础的知识点掌握要求。", "convertible": true, "correct_option": "homogeneous", "choice_question": "The formation of nuclei in a homogeneous liquid phase through conditions such as structural fluctuations and energy fluctuations is called:", "conversion_reason": "The answer is a standard term (homogeneous) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "homogeneous nucleation", "B": "heterogeneous nucleation", "C": "spinodal decomposition", "D": "Ostwald ripening" }, "correct_answer": "A", "explanation": "The correct answer is A because the question specifically describes nucleation occurring in a homogeneous liquid phase. Option B is incorrect as it refers to nucleation at interfaces or impurities. Option C is a phase separation mechanism, not nucleation. Option D describes particle coarsening after nucleation has occurred. The distractors exploit common confusions between different phase transformation mechanisms in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3219, "question": "The surface of a copper single crystal is parallel to {001}. If a tensile force is applied along the [001] direction, and the measured critical resolved shear stress is $\\overline{{\\tau_{c}}}=0.7$ MPa, determine the stress at which the material yields.", "answer": "The force is applied along the [001] direction, which is in a soft orientation with 8 equivalent slip systems. Taking one of them, (111)[overline{1}01], we have: $$ \\cos\\lambda={\\frac{1}{\\sqrt{2}}};\\cos\\varphi={\\frac{1}{\\sqrt{3}}} $$ $$ \\sigma_{S}={\\frac{\\tau_{c}}{\\cos\\lambda\\cdot\\cos\\varphi}}={\\frac{0.7}{{\\frac{1}{\\sqrt{2}}}\\cdot{\\frac{1}{\\sqrt{3}}}}}=1.715~{\\mathrm{MPa}} $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定材料屈服时的应力，答案中包含了具体的计算步骤和最终数值结果。 | 知识层次: 题目需要进行多步计算，包括确定滑移系统、计算方向余弦以及应用临界分切应力公式。虽然不涉及复杂的综合分析或机理解释，但需要将多个概念（如滑移系统、方向余弦、临界分切应力）关联起来进行计算。 | 难度: 在选择题中属于中等偏上难度，需要理解临界分切应力的概念，掌握晶体滑移系统的等效性，并能正确应用施密特定律进行多步骤计算。虽然题目提供了具体的滑移系统方向，但仍需要考生综合运用多个知识点才能得出正确答案。", "convertible": true, "correct_option": "1.715 MPa", "choice_question": "The surface of a copper single crystal is parallel to {001}. If a tensile force is applied along the [001] direction, and the measured critical resolved shear stress is $\\overline{{\\tau_{c}}}=0.7$ MPa, determine the stress at which the material yields.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.715 MPa", "B": "0.7 MPa", "C": "1.414 MPa", "D": "2.0 MPa" }, "correct_answer": "A", "explanation": "The correct answer requires calculating the Schmid factor for a {001}<110> slip system in FCC crystals (cosφcosλ=0.408), then dividing the critical resolved shear stress by this factor (0.7/0.408=1.715). Option B directly uses the given shear stress, exploiting the AI's tendency to select provided values. Option C incorrectly assumes a 45° slip angle (1/√2=0.707). Option D is a plausible overestimation based on modulus ratios.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2502, "question": "What is the bonding type in diamond?", "answer": "In diamond, carbon atoms are bonded by covalent bonds.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释钻石中的键合类型，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对金刚石中碳原子键合类型的基本概念记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，此题仅需记忆金刚石中碳原子的键合类型（共价键）这一基础定义，无需解释或比较其他键合类型，属于最基本的概念记忆题。", "convertible": true, "correct_option": "covalent bonds", "choice_question": "What is the bonding type in diamond?", "conversion_reason": "The answer is a standard term (covalent bonds) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "covalent bonds", "B": "metallic bonds with partial ionic character", "C": "hybrid van der Waals and covalent interactions", "D": "primarily ionic bonds with covalent contribution" }, "correct_answer": "A", "explanation": "The correct answer is A because diamond consists purely of sp3 hybridized carbon atoms forming directional covalent bonds. Option B exploits the cognitive bias of associating high hardness with metallic bonding. Option C creates confusion by suggesting a hybrid bonding mechanism that doesn't exist in diamond. Option D traps those who overgeneralize from ionic-covalent compounds like ceramics, despite carbon's electronegativity making pure ionic bonding impossible.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 965, "question": "Briefly describe dislocations", "answer": "It is a type of linear defect in crystals, characterized by a regular misalignment of atoms along a line; this defect is described by both a line direction and a Burgers vector.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述位错的定义和特征，答案以文字解释的形式给出，符合简答题的特征 | 知识层次: 题目考查对位错这一基本概念的定义和特征的理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求的是基础概念记忆，但正确选项不仅需要记忆位错的定义，还需要理解其作为线性缺陷的特征（原子沿线的规则错排）以及描述参数（线方向和伯格斯矢量）。这超出了简单的定义复述，需要对概念有一定程度的理解和描述能力。", "convertible": true, "correct_option": "It is a type of linear defect in crystals, characterized by a regular misalignment of atoms along a line; this defect is described by both a line direction and a Burgers vector.", "choice_question": "Which of the following best describes dislocations?", "conversion_reason": "The answer is a standard definition of a scientific term, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It is a type of linear defect in crystals, characterized by a regular misalignment of atoms along a line; this defect is described by both a line direction and a Burgers vector.", "B": "It is a two-dimensional defect where crystal planes terminate abruptly, creating an interface between perfect crystal regions with different orientations.", "C": "It is a point defect caused by thermal vibrations that temporarily displace atoms from their lattice sites, creating localized strain fields.", "D": "It is a volume defect formed by clustering of vacancies that creates a three-dimensional region of disordered atomic arrangement." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes dislocations as linear defects with both line direction and Burgers vector characteristics. Option B describes grain boundaries, a common confusion with dislocations. Option C describes a dynamic point defect phenomenon, exploiting thermal vibration misconceptions. Option D describes void clusters, using volume defect terminology that could mislead those unfamiliar with defect classification hierarchies.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2158, "question": "The critical resolved shear stress of an aluminum single crystal at room temperature is $7.9\\\\times10^{5}~\\\\mathrm{Pa}$. If a tensile test is performed on an aluminum single crystal specimen at room temperature with the tensile axis in the [123] direction, and the possible activated slip system is (111)[101], determine the stress required to cause the specimen to yield.", "answer": "The aluminum crystal has a face-centered cubic lattice, and its slip system is $\\\\{111\\\\}<110>$. When performing a tensile test on an aluminum single crystal: $$ \\\\sigma_{s}=\\\\frac{\\\\tau_{\\\\mathrm{c}}}{\\\\cos\\\\varphi\\\\cos\\\\lambda} $$ Given $\\\\tau_{\\\\mathrm{c}}=7.9\\\\times10^{5}~\\\\mathrm{Pa}$, when the external force axis direction is [123], the possible activated slip system is (111)[101]. Thus, $\\\\varphi$ is the angle between [123] and the normal [111] of the (111) crystal plane, and $\\\\lambda$ is the angle between [123] and [101]. $$ \\\\mathrm{cos}\\\\varphi={\\\\frac{{\\\\overline{{1}}}+2+3}{\\\\sqrt{14}\\\\times\\\\sqrt{3}}}={\\\\frac{4}{\\\\sqrt{42}}} $$ $$ \\\\cos\\\\lambda={\\\\frac{1+0+3}{\\\\sqrt{14}\\\\times{\\\\sqrt{2}}}}={\\\\frac{2}{\\\\sqrt{7}}} $$ Therefore, $$ \\\\sigma_{\\\\mathrm{s}}=\\\\frac{7.9\\\\times10^{5}}{\\\\frac{4}{\\\\sqrt{42}}\\\\times\\\\frac{2}{\\\\sqrt{7}}}=1.69\\\\times10^{6}~\\\\mathrm{Pa} $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定应力值，解答过程中涉及角度计算和临界分切应力的应用，最终得出具体的数值结果。 | 知识层次: 题目涉及多步计算，需要理解临界分切应力的概念，并应用施密特定律进行计算。同时需要计算晶体学方向之间的角度，涉及多个步骤和概念的综合应用。 | 难度: 在选择题中属于中等偏上难度，需要理解临界分切应力的概念，掌握晶体学方向指数的计算，并能正确应用施密特定律进行多步骤计算。题目涉及向量点积、角度计算和应力转换等综合分析步骤，对学生的空间想象力和数学计算能力有一定要求。虽然题目提供了具体方向和滑移系统，但计算过程较为复杂，属于综合性计算问题。", "convertible": true, "correct_option": "1.69×10⁶ Pa", "choice_question": "The critical resolved shear stress of an aluminum single crystal at room temperature is 7.9×10⁵ Pa. If a tensile test is performed on an aluminum single crystal specimen at room temperature with the tensile axis in the [123] direction, and the possible activated slip system is (111)[101], what is the stress required to cause the specimen to yield?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.69×10⁶ Pa", "B": "3.42×10⁶ Pa", "C": "7.9×10⁵ Pa", "D": "2.37×10⁶ Pa" }, "correct_answer": "A", "explanation": "正确答案A是通过正确计算施密特因子并应用临界分切应力公式得出的。干扰项B错误地使用了[101]方向而非[123]方向计算施密特因子。干扰项C直接使用了临界分切应力值而忽略了施密特因子的影响。干扰项D错误地将施密特因子计算为cos(45°)cos(54.7°)而非正确的值。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1760, "question": "The crystal structure is related to its (10) (11) and (12).", "answer": "(10) chemical composition; (11) relative size of particles; (12) polarization properties", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写具体的术语或概念，而不是从选项中选择或进行判断、计算。答案需要文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查晶体结构与其化学组成、粒子相对大小和极化性质之间关系的基本概念记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及晶体结构的基础概念记忆，但需要考生同时掌握化学组成、颗粒相对大小和极化特性三个相关知识点，并理解它们与晶体结构的关系。这比单纯记忆单一概念（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "chemical composition; relative size of particles; polarization properties", "choice_question": "The crystal structure is related to its:", "conversion_reason": "The original short answer question asks for specific properties related to crystal structure, which can be converted into a multiple-choice question by providing these properties as options. The correct answer is a standard set of terms that can be directly used as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "chemical composition and relative size of particles", "B": "temperature and pressure during formation", "C": "electrical conductivity and thermal expansion coefficient", "D": "optical transparency and magnetic susceptibility" }, "correct_answer": "A", "explanation": "The correct answer is A because crystal structure is fundamentally determined by the chemical composition (types of atoms/ions) and their relative sizes (radius ratio rules). B is a strong distractor as formation conditions do influence but do not fundamentally determine the crystal structure. C exploits the common misconception that macroscopic properties determine microstructure. D uses the cognitive bias of associating optical/magnetic properties with crystal symmetry without direct causation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1137, "question": "According to the phase rule, what is the degree of freedom when the ternary system has the maximum number of equilibrium phases?", "answer": "Zero", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据相律解释三元系统在最大平衡相数时的自由度，答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目考查对相律（phase rule）这一基本原理的记忆和理解，特别是关于自由度（degree of freedom）在特定条件下的直接应用。虽然涉及三元系统和最大平衡相数，但答案直接来源于相律的基本定义，不需要复杂的计算或综合分析。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目直接考察对相律基础概念的简单记忆，只需知道三元系统在最大平衡相数时的自由度为零即可选出正确选项，无需复杂推理或概念间的联系分析。", "convertible": true, "correct_option": "Zero", "choice_question": "According to the phase rule, what is the degree of freedom when the ternary system has the maximum number of equilibrium phases?", "conversion_reason": "The answer is a standard term and can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Zero", "B": "One", "C": "Two", "D": "Three" }, "correct_answer": "A", "explanation": "The correct answer is A (Zero) because according to the Gibbs phase rule (F = C - P + 2), for a ternary system (C=3) with the maximum number of equilibrium phases (P=5, at the invariant point), the degrees of freedom F = 3 - 5 + 2 = 0. Option B (One) is a common mistake when forgetting to account for the pressure variable in the phase rule. Option C (Two) exploits the confusion between binary and ternary systems, as binary systems at maximum phases would have F=2-3+2=1. Option D (Three) is designed to trap those who incorrectly apply the component count directly as degrees of freedom.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4669, "question": "Iron titanate, FeTiO3, forms in the ilmenite crystal structure that consists of an HCP arrangement of O2- ions. Which type of interstitial site will the Fe2+ ions occupy? Why?", "answer": "From Table, the cation-anion radius ratio is 0.077 nm / 0.140 nm = 0.550. Since this ratio is between 0.414 and 0.732, the Fe2+ ions will occupy octahedral sites.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释Fe2+离子占据哪种间隙位点及其原因，答案提供了基于半径比的计算和文字解释，属于需要论述的简答题类型。 | 知识层次: 题目需要应用半径比规则进行判断，涉及多步计算和概念关联，需要综合分析离子半径比与间隙位置的关系，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握离子半径比的计算方法，并能够根据计算结果判断离子占据的间隙位置类型。虽然涉及多步计算和概念关联，但在选择题型中，正确选项已经提供了关键的计算步骤和结论，降低了整体难度。因此，该题目在选择题型内属于等级3的难度。", "convertible": true, "correct_option": "octahedral sites", "choice_question": "Iron titanate, FeTiO3, forms in the ilmenite crystal structure that consists of an HCP arrangement of O2- ions. Which type of interstitial site will the Fe2+ ions occupy?", "conversion_reason": "The answer is a standard term (octahedral sites) which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "octahedral sites", "B": "tetrahedral sites", "C": "cubic sites", "D": "trigonal bipyramidal sites" }, "correct_answer": "A", "explanation": "The correct answer is A because in the ilmenite structure (FeTiO3), the Fe2+ ions occupy octahedral sites within the HCP arrangement of O2- ions. This is a characteristic feature of ilmenite-type structures where cations occupy octahedral coordination sites. Option B is a cognitive bias trap - while tetrahedral sites exist in HCP, Fe2+ prefers octahedral coordination in oxides. Option C exploits false intuition by suggesting a non-existent site type in HCP. Option D is a professional intuition trap using a real but irrelevant coordination geometry that doesn't occur in this structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1110, "question": "Degree of supercooling", "answer": "Degree of supercooling: Under rapid cooling conditions, when a metallic material cools to its melting point temperature, it does not solidify immediately but begins to solidify at a lower temperature. The difference between the actual solidification temperature and the melting point temperature is referred to as the degree of supercooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Degree of supercooling\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查对\"过冷度\"这一基本概念的定义和解释，属于基础概念的记忆和理解范畴，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆\"degree of supercooling\"的定义，即实际凝固温度与熔点温度之间的差值。虽然需要理解基本概念，但并不涉及复杂的概念体系或需要进行比较分析。该题目主要考察对基础概念的记忆和理解，属于选择题型中的中等难度。", "convertible": true, "correct_option": "Under rapid cooling conditions, when a metallic material cools to its melting point temperature, it does not solidify immediately but begins to solidify at a lower temperature. The difference between the actual solidification temperature and the melting point temperature is referred to as the degree of supercooling.", "choice_question": "Which of the following best describes the degree of supercooling?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting the definition as the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The temperature difference between the melting point and the actual solidification start point under rapid cooling", "B": "The maximum temperature drop achievable before nucleation occurs in an ideal undercooled liquid", "C": "The difference between glass transition temperature and crystallization temperature in amorphous alloys", "D": "The critical undercooling required to bypass all heterogeneous nucleation sites" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines supercooling as the temperature difference between thermodynamic melting point and actual solidification start. Option B misleads by suggesting an 'ideal maximum' rather than the actual observed difference. Option C exploits confusion with amorphous materials' behavior. Option D describes a special case of homogeneous nucleation threshold rather than the general supercooling phenomenon.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1404, "question": "According to the microscopic mechanism of diffusion, what are the basic types of diffusion?", "answer": "Interstitial diffusion and vacancy diffusion", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释扩散的基本类型，答案需要文字描述和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查扩散机制的基本类型，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 该题目属于基础概念记忆类型，仅需要学生回忆扩散机制的基本分类（间隙扩散和空位扩散）。在选择题型中，这类直接考察定义或分类的题目属于最简单级别，不需要解释或分析过程，只需识别正确选项即可。", "convertible": true, "correct_option": "Interstitial diffusion and vacancy diffusion", "choice_question": "According to the microscopic mechanism of diffusion, which of the following are the basic types of diffusion?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by rephrasing the question to ask for the correct option among choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial diffusion and vacancy diffusion", "B": "Fickian diffusion and non-Fickian diffusion", "C": "Thermal diffusion and pressure diffusion", "D": "Grain boundary diffusion and surface diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because interstitial and vacancy diffusion are the two fundamental microscopic mechanisms by which atoms move in crystalline solids. Option B describes macroscopic diffusion behaviors rather than microscopic mechanisms. Option C lists driving forces for diffusion, not atomic-scale mechanisms. Option D presents specialized diffusion pathways that are secondary to the basic mechanisms, exploiting the AI's tendency to prioritize more complex-sounding options.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3856, "question": "A steel contains 8 % cementite and 92 % ferrite at room temperature. Estimate the carbon content of the steel.", "answer": "the carbon content of the steel is 0.53 % c.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过计算来估计钢中的碳含量，需要使用材料科学中的相图或相关公式进行计算，答案是一个具体的数值结果。 | 知识层次: 题目需要应用基本的相图知识（铁碳相图）和简单的质量百分比计算，属于直接套用公式和基本概念的应用层次，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求根据给定的铁素体和渗碳体比例直接计算钢中的碳含量，这只需要应用基本的杠杆法则或相图比例关系，无需复杂的推导或多步骤计算。正确选项直接给出了计算结果，学生只需识别并应用正确的公式即可得出答案。", "convertible": true, "correct_option": "0.53 % c", "choice_question": "A steel contains 8 % cementite and 92 % ferrite at room temperature. What is the estimated carbon content of the steel?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.53 %", "B": "0.67 %", "C": "0.80 %", "D": "0.12 %" }, "correct_answer": "A", "explanation": "The correct answer is A (0.53%) because cementite contains 6.67% carbon, and the steel's carbon content can be calculated by multiplying the cementite fraction (8%) by 6.67%. Option B (0.67%) is a cognitive bias trap using cementite's carbon content directly. Option C (0.80%) exploits a common calculation error of adding ferrite's carbon solubility. Option D (0.12%) targets confusion with eutectoid composition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2607, "question": "Why is the relative atomic mass of an element not always a whole number?", "answer": "Because different isotopes contain varying numbers of neutrons (while having the same number of protons), elements with multiple isotopes in different abundances have a relative atomic mass that is not a whole number.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释为什么元素的相对原子质量不总是整数，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对同位素和相对原子质量的基本概念的理解，属于基础概念记忆和简单解释的范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要理解同位素的概念以及它们如何影响相对原子质量的计算。正确选项解释了不同同位素的中子数差异及其丰度对相对原子质量的影响，这超出了简单的定义记忆，需要对概念进行一定的解释和描述。因此，该题目在选择题型中属于等级2难度。", "convertible": true, "correct_option": "Because different isotopes contain varying numbers of neutrons (while having the same number of protons), elements with multiple isotopes in different abundances have a relative atomic mass that is not a whole number.", "choice_question": "Why is the relative atomic mass of an element not always a whole number?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because the atomic mass unit is defined relative to carbon-12, which itself has a non-integer mass", "B": "Because different isotopes contain varying numbers of neutrons while having the same number of protons", "C": "Due to relativistic effects that cause mass defects in atomic nuclei", "D": "Because electron cloud contributions to atomic mass vary with chemical environment" }, "correct_answer": "B", "explanation": "The correct answer is B because the relative atomic mass is a weighted average of all naturally occurring isotopes' masses. Option A is incorrect because while carbon-12 is used as the standard, its mass is defined as exactly 12 atomic mass units. Option C describes a real phenomenon but not the primary reason for non-integer atomic masses. Option D is incorrect because electron contributions to atomic mass are negligible.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 539, "question": "Polymorph", "answer": "Polymorph: Crystals of the same chemical composition that form different structures under varying thermodynamic conditions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Polymorph\"进行文字解释和论述，答案是一个定义性的陈述，符合简答题的特征。 | 知识层次: 题目考查对多晶型（Polymorph）这一基础概念的定义和基本特征的理解，属于材料科学中晶体结构的基础知识，主要依赖记忆和简单理解。 | 难度: 在选择题型中，该题目属于中等难度。虽然考查的是基础概念记忆（多晶型的定义），但需要考生准确理解并区分\"相同化学成分但不同晶体结构\"这一关键特征。相比简单定义复述（等级1），该选项要求对概念进行一定程度的解释和描述，但不需要涉及复杂的概念体系或比较分析（等级3）。在选择题型内，这属于典型的\"概念解释\"难度层级。", "convertible": true, "correct_option": "Crystals of the same chemical composition that form different structures under varying thermodynamic conditions.", "choice_question": "Which of the following best defines Polymorph?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Materials with identical chemical composition but different crystal structures due to processing history", "B": "Materials exhibiting reversible structural transformations under mechanical stress", "C": "Crystals of the same chemical composition that form different structures under varying thermodynamic conditions", "D": "Materials showing different physical properties while maintaining the same phase structure" }, "correct_answer": "C", "explanation": "The correct answer is C because polymorphs specifically refer to different crystal structures of the same chemical compound formed under different thermodynamic conditions. Option A is incorrect because processing history can affect microstructure but not necessarily create polymorphs. Option B describes shape memory alloys, not polymorphs. Option D describes anisotropic materials, not polymorphs. Advanced AI might confuse polymorphs with processing-induced microstructure changes (A) or reversible transformations (B), which are common misconceptions in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1901, "question": "What are the main mass transfer mechanisms in solid-state sintering?", "answer": "(28) Evaporation-condensation mass transfer; (29) Diffusion mass transfer", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和列举主要的固态烧结中的质量传递机制，答案以文字形式给出，没有选项或计算要求 | 知识层次: 题目考查固体烧结过程中主要传质机制的基础概念记忆和理解，属于定义和分类层面的知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求识别和记忆固体烧结过程中的主要传质机制，属于基础概念记忆层次。题目提供了明确的正确选项，无需进行复杂的分析或比较，因此难度较低。", "convertible": true, "correct_option": "Evaporation-condensation mass transfer; Diffusion mass transfer", "choice_question": "What are the main mass transfer mechanisms in solid-state sintering?", "conversion_reason": "The answer consists of standard terms or concepts that can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Evaporation-condensation mass transfer", "B": "Plastic deformation via dislocation motion", "C": "Grain boundary sliding controlled by creep", "D": "Surface diffusion dominated by curvature gradients" }, "correct_answer": "A", "explanation": "The correct answer is A because evaporation-condensation is one of the two primary mass transfer mechanisms in solid-state sintering (along with diffusion). Option B exploits the cognitive bias of associating sintering with plastic deformation, which is incorrect for solid-state sintering. Option C uses a real phenomenon (grain boundary sliding) but in the wrong context (creep deformation). Option D is a professional intuition trap, as surface diffusion is important but not a primary mass transfer mechanism in sintering.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1768, "question": "When 6 mol% of MgO is added to the UO2 lattice to form a substitutional solid solution, write the defect reaction equation.", "answer": "MgO→UO2Mg0′′+O0+V0∗", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求写出缺陷反应方程，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求写出缺陷反应方程，需要理解固溶体形成的基本原理和缺陷化学的知识，并能够将这些概念关联起来进行综合分析。虽然不涉及复杂的计算，但需要多步的逻辑推理和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解缺陷化学的基本概念，掌握离子替代和空位形成的原理，并能正确书写缺陷反应方程式。虽然题目涉及多步计算和概念关联，但在选择题型中，通过选项提示可以降低部分难度。", "convertible": true, "correct_option": "MgO→UO2Mg0′′+O0+V0∗", "choice_question": "When 6 mol% of MgO is added to the UO2 lattice to form a substitutional solid solution, which of the following is the correct defect reaction equation?", "conversion_reason": "The answer is a standard and specific defect reaction equation, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "MgO→UO2Mg0′′+O0+V0∗", "B": "MgO→UO2Mg0′′+O0+VO∗∗", "C": "MgO→UO2Mg0′′+Oi′′+VO∗∗", "D": "MgO→UO2Mg0′′+Oi′′+V0∗" }, "correct_answer": "A", "explanation": "The correct answer is A because Mg2+ substitutes for U4+ in the UO2 lattice, creating a negatively charged defect (Mg0′′) and requiring charge compensation through oxygen vacancies (V0∗). Option B incorrectly uses doubly charged oxygen vacancies (VO∗∗), which would overcompensate the charge. Option C introduces oxygen interstitials (Oi′′) which are unlikely in this substitution scenario. Option D combines oxygen interstitials with neutral vacancies, creating an energetically unfavorable configuration. The key is recognizing the correct charge balance between the substitutional defect and the compensating vacancy.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3211, "question": "A 20m long aluminum rod with a diameter of 14.0mm is drawn through a die with an aperture of 12.7mm. Calculate the true strain experienced by this aluminum rod.", "answer": "True strain e=ln(L/L0)=ln(24.3/20)=19.47%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（使用对数公式计算真实应变）来得出具体数值结果，符合计算题的特征。 | 知识层次: 题目主要考查基本公式（真实应变公式）的直接应用和简单计算，不需要多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（true strain公式）进行计算，无需额外的概念理解或步骤组合。解题过程简单直接，属于最基础的难度等级。", "convertible": true, "correct_option": "19.47%", "choice_question": "A 20m long aluminum rod with a diameter of 14.0mm is drawn through a die with an aperture of 12.7mm. The true strain experienced by this aluminum rod is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "19.47%", "B": "17.82%", "C": "21.35%", "D": "23.14%" }, "correct_answer": "A", "explanation": "The correct answer is A (19.47%) because the true strain is calculated using the natural logarithm of the area ratio, ln(A0/Af), where A0 is the initial cross-sectional area and Af is the final cross-sectional area. Option B (17.82%) is designed to trap those who incorrectly use diameter ratios directly without considering the area. Option C (21.35%) exploits the common mistake of using engineering strain instead of true strain. Option D (23.14%) is a close but incorrect value that might result from miscalculating the area ratio or misapplying the logarithmic function.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 190, "question": "In $2080^{\\\\circ}\\\\mathrm{C}$ $\\\\mathrm{Al_{2}O_{3}}$ (L), there is a small bubble with a radius of $10~\\\\mathrm{^{-8}m}$. What is the additional pressure experienced by the bubble? It is known that the surface tension of $\\\\mathrm{Al_{2}O_{3}}$ (L) at $2080^{\\\\circ}\\\\mathrm{C}$ is $0.700\\\\mathrm{N/m}$.", "answer": "According to the formula $\\\\triangle P=2y$, the additional pressure can be calculated as $\\\\triangle P{=}2\\\\times0.7/10^{-8}{=}1.$ $4\\\\times10^{8}\\\\mathrm{N}$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过公式计算气泡的额外压力，答案给出了具体的计算过程和数值结果，符合计算题的特征。 | 知识层次: 题目主要考查基本公式（Laplace压力公式）的直接应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（△P=2y）进行计算，无需理解多个概念或进行复杂的分析。解题步骤简单，仅涉及基本公式应用和简单计算，属于最基础的难度等级。", "convertible": true, "correct_option": "$1.4\\times10^{8}\\mathrm{N}$", "choice_question": "In $2080^{\\circ}\\mathrm{C}$ $\\mathrm{Al_{2}O_{3}}$ (L), there is a small bubble with a radius of $10~\\mathrm{^{-8}m}$. What is the additional pressure experienced by the bubble? It is known that the surface tension of $\\mathrm{Al_{2}O_{3}}$ (L) at $2080^{\\circ}\\mathrm{C}$ is $0.700\\mathrm{N/m}$.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.4×10^8 N/m²", "B": "0.7×10^8 N/m²", "C": "2.8×10^8 N/m²", "D": "0.35×10^8 N/m²" }, "correct_answer": "A", "explanation": "正确答案A使用拉普拉斯压力公式ΔP=2γ/r计算，其中γ=0.700N/m，r=10^-8m。干扰项B错误地忽略了系数2，是常见计算错误。干扰项C错误地使用了4γ/r，混淆了气泡和液滴的公式。干扰项D错误地将半径取为2×10^-8m，是单位换算陷阱。这些干扰项利用了表面张力计算中常见的系数混淆和单位错误认知偏差。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4678, "question": "Compare thermoplastic and thermosetting polymers on the basis of mechanical characteristics upon heating.", "answer": "Thermoplastic polymers soften when heated and harden when cooled, whereas thermosetting polymers harden upon heating, while further heating will not lead to softening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较两种聚合物在加热时的机械特性，需要文字解释和论述，而不是选择、判断或计算。答案提供了详细的解释，符合简答题的特征。 | 知识层次: 题目考查对热塑性聚合物和热固性聚合物基本特性的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生同时理解和区分两种聚合物（热塑性和热固性）在加热时的不同机械特性。正确选项不仅要求记忆各自定义，还需要进行简单的对比分析。这比单纯记忆单一概念（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Thermoplastic polymers soften when heated and harden when cooled, whereas thermosetting polymers harden upon heating, while further heating will not lead to softening.", "choice_question": "Which of the following correctly compares thermoplastic and thermosetting polymers on the basis of mechanical characteristics upon heating?", "conversion_reason": "The answer is a standard comparison between two types of polymers, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermoplastic polymers exhibit reversible softening upon heating due to breaking of secondary bonds, while thermosetting polymers undergo irreversible crosslinking that prevents softening at any temperature", "B": "Both polymer types soften upon initial heating, but thermosets develop higher elastic modulus upon cooling due to crystalline domain formation", "C": "Thermosetting polymers show greater thermal expansion coefficients than thermoplastics, leading to faster softening at elevated temperatures", "D": "The glass transition temperature marks the softening point for thermoplastics, while thermosets maintain rigidity until reaching decomposition temperature" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the fundamental difference: thermoplastics soften reversibly through secondary bond breaking, while thermosets form irreversible crosslinks. Distractors employ sophisticated traps: B falsely introduces crystalline domains in thermosets (they're amorphous), C conflates thermal expansion with softening mechanism, and D incorrectly applies Tg concept to thermosets which don't exhibit this transition. These distractors exploit advanced material science concepts that require nuanced understanding beyond surface-level knowledge.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3317, "question": "Describe the microstructure type, obtaining conditions, characteristics, and mechanical properties of steel after high-temperature tempering", "answer": "High-temperature tempering Tempered sorbite 500-650℃ Good combination of strength and toughness", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述高温回火后钢的微观结构类型、获得条件、特征和机械性能，需要文字解释和论述，答案也以简短的文字形式呈现。 | 知识层次: 题目要求描述高温回火后钢的微观结构类型、获得条件、特征和力学性能，涉及多个知识点的关联和综合分析，需要理解回火温度对钢性能的影响机制，并能够将微观结构与宏观性能联系起来。这超出了单纯记忆基础概念的层次，属于中等应用水平。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生综合掌握高温回火后的钢的微观结构类型、获得条件、特性以及力学性能，并能够将这些知识点关联起来。虽然题目给出了正确选项，但考生仍需具备一定的综合分析能力才能准确选择。", "convertible": true, "correct_option": "High-temperature tempering Tempered sorbite 500-650℃ Good combination of strength and toughness", "choice_question": "Which of the following describes the microstructure type, obtaining conditions, characteristics, and mechanical properties of steel after high-temperature tempering?", "conversion_reason": "The answer is a standard terminology and concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High-temperature tempering Tempered sorbite 500-650℃ Good combination of strength and toughness", "B": "High-temperature tempering Tempered martensite 300-500℃ High hardness with reduced brittleness", "C": "High-temperature tempering Pearlite 650-700℃ Excellent ductility with moderate strength", "D": "High-temperature tempering Bainite 400-550℃ Superior toughness with retained hardness" }, "correct_answer": "A", "explanation": "The correct answer is A because high-temperature tempering (500-650℃) produces tempered sorbite microstructure which provides the best balance of strength and toughness. Option B is incorrect as tempered martensite forms at lower temperatures (300-500℃). Option C is wrong because pearlite forms during slow cooling, not tempering. Option D is misleading as bainite forms during continuous cooling, not tempering processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3713, "question": "Calculate the maximum force that a 0.2 -in. diameter rod of \\mathrm{Al}_{2} \\mathrm{O}_{3}, having a yield strength of 35,000 psi, can withstand with no plastic deformation. Express your answer in pounds and Newtons.", "answer": "the maximum force the rod can withstand is 1100 lb or 4891 n.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算最大受力），需要使用公式（强度与受力关系公式），答案以具体数值形式给出（1100 lb或4891 N），这些都是计算题的典型特征。 | 知识层次: 题目考查基本公式的应用和简单计算，只需要根据给定的直径和屈服强度计算最大受力，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（应力=力/面积）进行计算，无需复杂的步骤或多公式组合。题目提供了所有必要的数据，且计算过程简单直接，属于最基础的难度等级。", "convertible": true, "correct_option": "1100 lb or 4891 N", "choice_question": "What is the maximum force that a 0.2-in. diameter rod of Al₂O₃, having a yield strength of 35,000 psi, can withstand with no plastic deformation?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1100 lb (4891 N)", "B": "1750 lb (7785 N)", "C": "875 lb (3893 N)", "D": "2200 lb (9786 N)" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the yield strength and cross-sectional area (F = σ_y × A). For a 0.2-in diameter rod, A = π×(0.1)^2 = 0.0314 in², giving F = 35,000 psi × 0.0314 in² = 1100 lb. Option B incorrectly uses tensile strength instead of yield strength. Option C is half the correct value, tempting those who forget to square the radius. Option D doubles the correct answer, targeting those who confuse diameter with radius in the area calculation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3290, "question": "What is the effect of pearlite interlamellar spacing and pearlite colonies on mechanical properties?", "answer": "The lower the formation temperature, the smaller the size of pearlite colonies and interlamellar spacing, the finer the pearlite structure, and the higher the strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释珠光体层间距和珠光体团对机械性能的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解珠光体层间距和珠光体团对力学性能的影响，并能够分析温度变化对微观结构的影响及其与强度的关系。这涉及到多个概念的关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解珠光体层间距和珠光体团对力学性能的影响，并综合分析温度、尺寸和强度之间的关系。虽然涉及多个概念，但在选择题型中通过选项可以辅助判断，不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "The lower the formation temperature, the smaller the size of pearlite colonies and interlamellar spacing, the finer the pearlite structure, and the higher the strength.", "choice_question": "What is the effect of pearlite interlamellar spacing and pearlite colonies on mechanical properties?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Smaller interlamellar spacing increases hardness but reduces ductility due to restricted dislocation movement", "B": "Larger pearlite colonies improve toughness by providing more uniform stress distribution", "C": "Finer pearlite structure decreases both strength and hardness due to increased boundary area", "D": "Pearlite colony size has negligible effect compared to cementite morphology" }, "correct_answer": "A", "explanation": "The correct answer is A because finer pearlite (smaller spacing) increases strength by restricting dislocation movement, though it does reduce ductility. B is incorrect because larger colonies actually create stress concentration points. C is a reversal trap - finer structure increases strength. D is wrong as colony size significantly affects crack propagation paths.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 153, "question": "Which substances can form non-crystalline solids (NCS)?", "answer": "Melts and glassy solids can form non-crystalline solids.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释哪些物质可以形成非晶态固体，答案需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查对非晶态固体形成物质的基础概念记忆和理解，属于定义和分类的基本知识。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即非晶态固体（NCS）的形成物质类型。正确选项直接给出了明确的定义性答案（熔体和玻璃态固体），无需任何推理或分析过程。这属于最基础的定义识别类题目，完全符合等级1\"基本定义简答\"的特征。在选择题难度谱系中，此类只需机械记忆即可作答的题目属于最低难度层级。", "convertible": true, "correct_option": "Melts and glassy solids", "choice_question": "Which of the following can form non-crystalline solids (NCS)?", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by rephrasing the question to 'Which of the following...' and providing the correct option as one of the choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metallic alloys under rapid quenching", "B": "Ionic crystals at room temperature", "C": "Polycrystalline ceramics with grain boundaries", "D": "Single crystal semiconductors" }, "correct_answer": "A", "explanation": "Correct answer is A because rapid quenching of metallic alloys can prevent atomic rearrangement, forming metallic glasses (non-crystalline solids). B is incorrect as ionic crystals inherently form ordered structures at room temperature. C is a cognitive bias trap - while grain boundaries exist, the material remains crystalline. D exploits professional intuition by using 'single crystal' which implies perfect crystallinity, though some might associate semiconductors with amorphous phases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4789, "question": "For the following pair of polymers, do the following: (1) state whether it is possible to decide whether one polymer has a higher tensile modulus than the other; (2) if this is possible, note which has the higher tensile modulus and cite the reason(s) for your choice; and (3) if it is not possible to decide, state why. Branched and atactic poly(vinyl chloride) with a weight-average molecular weight of 100,000 g/mol; linear and isotactic poly(vinyl chloride) having a weight-average molecular weight of 75,000 g/mol", "answer": "Yes, it is possible. The linear and isotactic poly(vinyl chloride) will display a greater tensile modulus. Linear polymers are more likely to crystallize that branched ones. In addition, polymers having isotactic structures will normally have a higher degree of crystallinity that those having atactic structures. Increasing a polymer's crystallinity leads to an increase in its tensile modulus. In addition, tensile modulus is independent of molecular weight - the atactic/branched material has the higher molecular weight.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对两种聚合物的拉伸模量进行比较，并解释原因。答案需要详细的文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目要求考生比较两种聚合物的拉伸模量，并解释原因。这需要理解聚合物结构（支化、线性、等规、无规）对结晶度和力学性能的影响，以及分子量对拉伸模量的影响。虽然不涉及复杂计算，但需要综合分析多个因素（结构、结晶度、分子量）并关联到性能，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，需要考生进行多角度分析论述。题目要求考生不仅理解聚合物的结构（支化与线性、无规与等规）对拉伸模量的影响，还需要掌握结晶度与拉伸模量的关系，以及分子量对拉伸模量的影响。此外，题目还要求考生能够综合分析这些因素，并做出正确的判断和解释。这种题目在选择题型中属于较为复杂的类型，需要考生具备较高的知识掌握深度和综合分析能力。", "convertible": true, "correct_option": "The linear and isotactic poly(vinyl chloride) will display a greater tensile modulus.", "choice_question": "For the following pair of polymers, which one has a higher tensile modulus? Branched and atactic poly(vinyl chloride) with a weight-average molecular weight of 100,000 g/mol; linear and isotactic poly(vinyl chloride) having a weight-average molecular weight of 75,000 g/mol", "conversion_reason": "The original question asks for a comparison between two polymers regarding their tensile modulus, and the answer provides a clear choice with reasoning. This can be converted into a multiple-choice question by presenting the answer as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The branched and atactic PVC due to its higher molecular weight enhancing chain entanglement", "B": "The linear and isotactic PVC because crystallinity dominates over molecular weight effects", "C": "Cannot be determined without knowing the degree of branching in the atactic polymer", "D": "Both would have similar modulus as vinyl chloride's properties are insensitive to tacticity" }, "correct_answer": "B", "explanation": "The correct answer is B because linear and isotactic PVC can crystallize, significantly increasing its modulus despite lower molecular weight. Option A is a cognitive bias trap - while higher MW increases entanglement, branching and atacticity prevent crystallization. Option C is a verification trap - while branching degree matters, tacticity's crystallinity effect dominates. Option D is a professional intuition trap - tacticity dramatically affects vinyl chloride polymers' crystallinity and mechanical properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 544, "question": "3. In a ternary phase diagram, the eutectic point is (6) phase equilibrium, and the degree of freedom is (7).", "answer": "(6) four; (7) 0", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的答案（如“four”和“0”），而不是从多个选项中选择或进行判断。虽然答案简短，但属于填空题或简答题的范畴，需要根据知识直接回答。 | 知识层次: 题目考查对三元相图中共晶点的相平衡和自由度等基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即三元相图中共晶点的相平衡数量和自由度数值。题目直接给出了正确选项，无需复杂推理或概念间的联系分析，属于最基础的定义简答类型。", "convertible": true, "correct_option": "four; 0", "choice_question": "In a ternary phase diagram, the eutectic point is (6) phase equilibrium, and the degree of freedom is (7).", "conversion_reason": "The short answer question has a specific and standard answer, making it suitable for conversion to a multiple-choice format. The correct option can be directly derived from the provided answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "four; 0", "B": "three; 1", "C": "two; 2", "D": "three; 0" }, "correct_answer": "A", "explanation": "The correct answer is A because at the eutectic point in a ternary phase diagram, four phases (three solid phases and one liquid phase) are in equilibrium, and the degree of freedom is 0 according to Gibbs phase rule. Option B is incorrect because it underestimates the number of phases and overestimates the degrees of freedom, exploiting the common confusion with binary systems. Option C is wrong as it represents a typical binary system equilibrium, creating a cognitive bias from simpler phase diagrams. Option D correctly identifies zero degrees of freedom but incorrectly states three phases, playing on the intuitive but incorrect assumption that ternary systems always have three phases at equilibrium points.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4773, "question": "A single crystal of zinc is oriented for a tensile test such that its slip plane normal makes an angle of 65 degrees with the tensile axis. Three possible slip directions make angles of 30 degrees, 48 degrees, and 78 degrees with the same tensile axis. Which of these three slip directions is most favored?", "answer": "the most favored slip direction is at an angle of 30 degrees with the tensile axis.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述哪个滑移方向最有利，而不是从给定的选项中选择答案。答案需要基于对滑移方向和角度关系的理解进行解释。 | 知识层次: 题目需要理解滑移面和滑移方向的概念，并应用施密特定律（Schmid's Law）计算不同滑移方向的施密特因子（Schmid factor），然后比较这些因子以确定最有利的滑移方向。这涉及多步计算和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及晶体滑移方向的选择，需要考生掌握滑移面、滑移方向与拉伸轴夹角的关系，并能够计算和比较不同滑移方向的施密特因子（Schmid factor）。虽然题目给出了具体角度，但仍需考生理解哪个角度最有利于滑移（即施密特因子最大），这需要一定的综合分析能力。", "convertible": true, "correct_option": "the most favored slip direction is at an angle of 30 degrees with the tensile axis", "choice_question": "A single crystal of zinc is oriented for a tensile test such that its slip plane normal makes an angle of 65 degrees with the tensile axis. Three possible slip directions make angles of 30 degrees, 48 degrees, and 78 degrees with the same tensile axis. Which of these three slip directions is most favored?", "conversion_reason": "The answer is a specific choice among given options, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "the most favored slip direction is at an angle of 30 degrees with the tensile axis", "B": "the most favored slip direction is at an angle of 48 degrees with the tensile axis", "C": "the most favored slip direction is at an angle of 78 degrees with the tensile axis", "D": "all three slip directions are equally favored due to the high angle of the slip plane normal" }, "correct_answer": "A", "explanation": "The correct answer is A because the most favored slip direction is the one that maximizes the Schmid factor (cosφ * cosλ), where φ is the angle between the slip plane normal and tensile axis (65°), and λ is the angle between the slip direction and tensile axis. The 30° slip direction yields the highest Schmid factor. Option B is a cognitive bias trap, as 48° is midway between the extremes and might seem 'balanced'. Option C exploits the misconception that higher angles always favor slip. Option D is a multi-level trap combining incorrect assumptions about slip plane angle dominance with equal probability fallacy.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1996, "question": "What is the difference between a space lattice and a crystal lattice?", "answer": "A crystal lattice, also known as a crystal structure, refers to the specific arrangement of atoms; whereas a space lattice abstracts atoms as pure geometric points by ignoring their volume.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两个概念之间的区别，答案需要文字论述和解释，没有提供选项或要求判断对错或进行数值计算。 | 知识层次: 题目考查对空间点阵和晶体点阵这两个基本概念的定义和区别的记忆和理解，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个相关概念（空间点阵和晶体点阵）的比较，但正确选项提供了清晰的定义和区分，不需要复杂的推理或深入的概念体系理解。主要考察的是对基础概念的记忆和简单解释能力，符合等级2“概念解释和描述”的要求。", "convertible": true, "correct_option": "A crystal lattice, also known as a crystal structure, refers to the specific arrangement of atoms; whereas a space lattice abstracts atoms as pure geometric points by ignoring their volume.", "choice_question": "What is the difference between a space lattice and a crystal lattice?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A space lattice describes the periodic arrangement of unit cells, while a crystal lattice includes the actual atomic positions within those unit cells", "B": "A space lattice is the mathematical abstraction of a crystal lattice, where atoms are represented as dimensionless points", "C": "A crystal lattice is the 3D arrangement of atoms, while a space lattice is its 2D projection used in diffraction analysis", "D": "Space lattice refers to metallic crystals only, while crystal lattice applies to all crystalline materials" }, "correct_answer": "B", "explanation": "The correct answer B precisely distinguishes that a space lattice is the mathematical abstraction (points) while a crystal lattice includes real atomic arrangements. Option A reverses the definitions. Option C incorrectly introduces 2D projection. Option D falsely limits space lattice to metals. The key cognitive trap is that space lattice sounds more 'physical' than it actually is, leading to intuitive reversal errors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2199, "question": "What is the difference between crazing and cracking?", "answer": "Crazing is different from cracking. The two open surfaces of a crack are completely empty, whereas the surfaces of a craze consist of highly oriented fiber bundles and voids, which still retain some strength. The formation of crazes is due to localized yielding and cold drawing of the material under tensile stress.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两个概念之间的区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对材料科学中基本概念（crazing和cracking）的记忆和理解，主要涉及定义和基本特征的区分，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生理解并区分两个相关概念（crazing和cracking），并能够识别它们的关键差异。虽然涉及多个知识点，但主要考察的是对基础概念的解释和描述，而非复杂的分析或综合应用。因此属于中等难度（等级2）。", "convertible": true, "correct_option": "Crazing is different from cracking. The two open surfaces of a crack are completely empty, whereas the surfaces of a craze consist of highly oriented fiber bundles and voids, which still retain some strength. The formation of crazes is due to localized yielding and cold drawing of the material under tensile stress.", "choice_question": "What is the difference between crazing and cracking?", "conversion_reason": "The answer is a standard explanation of the difference between crazing and cracking, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crazing involves localized yielding forming fibrillated structures, while cracking is complete material separation", "B": "Crazing occurs in ductile materials only, whereas cracking happens in brittle materials", "C": "Crazing is reversible upon stress removal, while cracking is permanent", "D": "Crazing represents atomic-scale defects, whereas cracking is macroscopic failure" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the key difference: crazing forms fibrillated structures with residual strength, while cracking is complete separation. Option B is wrong because crazing can occur in both ductile and brittle materials. Option C exploits the 'reversible deformation' cognitive bias - while crazing may appear reversible visually, it's actually permanent. Option D misleads by suggesting crazing is atomic-scale, when it's actually a microscopic phenomenon.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3306, "question": "Compare the hardness of the transformation products of bainite transformation, pearlite transformation, and martensite transformation", "answer": "The pearlite transformation product has low hardness, the bainite transformation product has medium hardness, and the martensite transformation product has high hardness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较不同转变产物的硬度，答案需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对三种相变产物硬度的基本记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个相变产物（珠光体、贝氏体、马氏体）的硬度比较，但只需要记忆和区分它们的基本硬度特征即可作答，无需深入理解相变机制或进行复杂分析。这属于\"概念解释和描述\"层次的知识应用。", "convertible": true, "correct_option": "The pearlite transformation product has low hardness, the bainite transformation product has medium hardness, and the martensite transformation product has high hardness.", "choice_question": "Which of the following correctly compares the hardness of the transformation products of bainite transformation, pearlite transformation, and martensite transformation?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question because the answer is a specific comparison of hardness levels, which can be presented as one of several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pearlite has low hardness, bainite has medium hardness, martensite has high hardness", "B": "Pearlite has high hardness due to its lamellar structure, bainite has medium hardness, martensite has the lowest hardness", "C": "Bainite has the highest hardness due to its fine microstructure, followed by martensite, with pearlite being the softest", "D": "Martensite has medium hardness due to its tetragonal structure, pearlite has the highest hardness, bainite is the softest" }, "correct_answer": "A", "explanation": "The correct answer is A because pearlite, formed by diffusion-controlled transformation, has relatively low hardness; bainite, formed by intermediate transformation, has medium hardness; and martensite, formed by diffusionless transformation, has the highest hardness due to its highly distorted structure. Option B incorrectly states pearlite has high hardness due to lamellar structure - while lamellar, it's still softer than martensite. Option C reverses the hardness ranking between bainite and martensite, exploiting the intuition that finer microstructures are always harder. Option D contains multiple errors, particularly the claim about martensite's medium hardness, which contradicts fundamental materials science principles.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1868, "question": "What is secondary recrystallization?", "answer": "Secondary recrystallization is an abnormal growth process where a few large grains grow at the expense of fine grains, representing the abnormal growth of individual grains. During secondary recrystallization, pores are enclosed within the grains, and it is also related to the particle size of the raw material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"secondary recrystallization\"进行文字解释和论述，答案提供了详细的定义和特征描述，符合简答题的特点。 | 知识层次: 题目考查对二次再结晶这一基础概念的定义和基本特征的理解，属于记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆二次再结晶的定义及其特征，包括异常晶粒生长过程、孔隙被包裹在晶粒内以及与原料颗粒尺寸的关系。虽然涉及多个知识点，但都属于基础概念的记忆和理解范畴，不需要复杂的分析或比较。因此，难度适中，属于等级2。", "convertible": true, "correct_option": "Secondary recrystallization is an abnormal growth process where a few large grains grow at the expense of fine grains, representing the abnormal growth of individual grains. During secondary recrystallization, pores are enclosed within the grains, and it is also related to the particle size of the raw material.", "choice_question": "Which of the following best describes secondary recrystallization?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as the correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An abnormal growth process where a few large grains grow at the expense of fine grains, with pores enclosed within the grains", "B": "A uniform grain growth process driven by surface energy reduction, resulting in equiaxed grain structure", "C": "The nucleation of new grains at high temperatures, replacing the original deformed microstructure", "D": "A diffusion-controlled process where small grains dissolve to feed the growth of larger grains along temperature gradients" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes secondary recrystallization's key features: abnormal growth of select grains and pore enclosure. Option B describes normal grain growth, exploiting the common confusion between normal and abnormal growth processes. Option C mimics primary recrystallization terminology to trigger incorrect first impressions. Option D combines accurate diffusion mechanisms with incorrect temperature gradient dependence, creating a plausible but wrong scenario.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4214, "question": "For alloy C with atomic weight 127.3 g/mol, density 9.23 g/cm³, and atomic radius 0.142 mm, determine whether its crystal structure is FCC, BCC, or simple cubic and then justify your determination.", "answer": "for alloy c, its crystal structure is simple cubic.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求确定合金的晶体结构并给出合理的解释，需要文字解释和论述，而不仅仅是选择或计算。 | 知识层次: 题目需要根据给定的原子重量、密度和原子半径，通过多步计算和综合分析来确定晶体结构类型（FCC、BCC或简单立方）。这涉及到对晶体结构基本概念的理解、相关公式的应用（如密度与晶格参数的关系）以及逻辑推理能力。虽然不涉及复杂的机理分析或创新设计，但需要一定的计算步骤和概念关联，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合运用密度公式、晶体结构几何关系、单位换算等多步骤计算，并关联原子半径与晶格参数的关系进行综合分析判断。题目要求考生不仅要掌握各晶体结构的堆积特征，还需具备将理论公式与给定数据结合推导的能力，属于典型的中等应用层次综合分析题。", "convertible": true, "correct_option": "simple cubic", "choice_question": "For alloy C with atomic weight 127.3 g/mol, density 9.23 g/cm³, and atomic radius 0.142 mm, its crystal structure is:", "conversion_reason": "The answer is a standard term (simple cubic) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Simple cubic", "B": "Face-centered cubic (FCC)", "C": "Body-centered cubic (BCC)", "D": "Hexagonal close-packed (HCP)" }, "correct_answer": "A", "explanation": "The correct answer is A (Simple cubic) because the calculated packing factor (0.52) matches the theoretical value for simple cubic structure. Option B (FCC) is designed to exploit the cognitive bias that most common metals have FCC or BCC structures. Option C (BCC) is a trap for those who miscalculate the atomic packing factor. Option D (HCP) is included to test if the solver considers the given parameters are for a cubic system only.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3983, "question": "During the recrystallization of a cold-worked material, is there some reduction in the number of dislocations?", "answer": "There is significant reduction in the number of dislocations.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（即是否在再结晶过程中位错数量会减少），答案直接给出了判断结果（位错数量显著减少），符合判断题的特征。 | 知识层次: 题目考查对再结晶过程中位错数量变化的基本概念的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目直接询问冷加工材料再结晶过程中位错数量是否减少，正确选项明确陈述了\"位错数量显著减少\"这一基础概念。这只需要学生对再结晶过程的基本定义和原理有记忆性知识即可正确回答，无需深入理解或分析多个概念。因此按照选择题型的难度分级标准，这属于等级1的基础概念正误判断题。", "convertible": true, "correct_option": "There is significant reduction in the number of dislocations.", "choice_question": "During the recrystallization of a cold-worked material, is there some reduction in the number of dislocations?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All cold-worked materials will completely eliminate dislocations during recrystallization.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While recrystallization significantly reduces dislocation density in cold-worked materials, it rarely eliminates all dislocations. The statement uses an absolute term 'all' which is incorrect. Some dislocations typically remain due to factors like incomplete recrystallization, new dislocations forming during grain growth, or impurities pinning dislocations. This tests understanding of recrystallization limits and the danger of absolute statements in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4457, "question": "How do the aggregate particles become bonded together in clay-based mixtures during firing?", "answer": "For clay-based aggregates, a liquid phase forms during firing, which infiltrates the pores between the unmelted particles; upon cooling, this liquid becomes a glass, that serves as the bonding phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释粘土基混合物在烧制过程中颗粒如何结合，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释粘土基混合物在烧制过程中颗粒如何结合，涉及液相形成、渗透和冷却过程中的玻璃化转变等复杂机理，需要综合运用材料科学知识进行推理分析。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "For clay-based aggregates, a liquid phase forms during firing, which infiltrates the pores between the unmelted particles; upon cooling, this liquid becomes a glass, that serves as the bonding phase.", "choice_question": "How do the aggregate particles become bonded together in clay-based mixtures during firing?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A liquid phase forms during firing, infiltrates particle pores, and becomes a glassy bonding phase upon cooling", "B": "Direct solid-state diffusion bonding occurs between clay particles at high temperatures", "C": "Surface hydroxyl groups on clay particles chemically react to form covalent bonds", "D": "Partial melting creates interlocking crystal structures that mechanically bond particles" }, "correct_answer": "A", "explanation": "The correct answer describes the actual liquid-phase sintering mechanism in clay firing. Option B exploits the common misconception about solid-state diffusion in ceramics. Option C uses surface chemistry intuition that applies to room-temperature bonding but not firing conditions. Option D creates confusion with metallic sintering mechanisms by suggesting mechanical interlocking.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3408, "question": "Explain the meaning of the steel grade 16Mn", "answer": "16Mn is a low-alloy structural steel, wc=0.16%, 10Mn=1.4%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释16Mn钢的含义，答案提供了详细的文字解释和具体成分数据，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对钢材牌号16Mn的基本概念记忆和理解，包括其分类（低合金结构钢）和成分（碳含量和锰含量）等基本信息，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆和识别16Mn钢的基本定义和成分信息，属于基础概念记忆层次。题目仅涉及简单的定义和数值记忆，不需要复杂的解释或分析，因此属于最低难度等级。", "convertible": true, "correct_option": "16Mn is a low-alloy structural steel, wc=0.16%, 10Mn=1.4%", "choice_question": "Which of the following correctly describes the meaning of the steel grade 16Mn?", "conversion_reason": "The answer is a standard description of the steel grade 16Mn, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "16Mn is a low-alloy structural steel, wc=0.16%, wMn=1.4%", "B": "16Mn is a high-carbon tool steel with 16% Mn content for wear resistance", "C": "16Mn represents a stainless steel grade with 16% Cr and balanced Mn", "D": "16Mn indicates a dual-phase steel with 16% ferrite and 84% martensite" }, "correct_answer": "A", "explanation": "Correct answer A follows standard Chinese steel designation where the number indicates carbon content (0.16%) and Mn content (1.4%). Option B exploits the common misconception that high Mn content implies tool steel. Option C creates confusion by mixing stainless steel nomenclature. Option D misleads by suggesting phase composition which is unrelated to the naming convention.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 331, "question": "What is the main difference between slip and twinning?", "answer": "The shear displacement produced by slip is an integer multiple of the atomic spacing, while that produced by twinning is a fraction of the atomic spacing; this leads to a series of other differences.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释slip和twinning的主要区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对滑移和孪生这两种塑性变形机制的基本概念的理解和记忆，主要涉及定义和基本原理的对比，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解并区分两种变形机制（滑移和孪生）的关键差异，即剪切位移与原子间距的关系。这超出了简单的定义记忆，要求考生能够解释和描述概念之间的区别。不过，题目并未涉及复杂的多概念体系分析或深入的应用，因此属于等级2难度。", "convertible": true, "correct_option": "The shear displacement produced by slip is an integer multiple of the atomic spacing, while that produced by twinning is a fraction of the atomic spacing; this leads to a series of other differences.", "choice_question": "What is the main difference between slip and twinning?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip involves dislocation motion while twinning requires coordinated atomic shuffling", "B": "Slip preserves crystal orientation whereas twinning creates mirror-image lattice regions", "C": "Slip occurs at lower stresses than twinning in all crystalline materials", "D": "Slip produces macroscopic shape change while twinning only affects microscopic structure" }, "correct_answer": "A", "explanation": "Correct answer A captures the fundamental mechanistic difference: slip's dislocation motion versus twinning's atomic shuffling. Option B is a common misconception - while orientation change is true for twinning, slip planes also show subtle orientation changes. Option C exploits the AI's tendency to overgeneralize - the stress requirement actually depends on crystal structure and temperature. Option D targets the AI's difficulty in distinguishing length scales - both mechanisms can produce macroscopic effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2451, "question": "At 627°C (i.e., 900K), what is the solubility of Fe3C particles with a radius of 100nm in α-Fe? The interfacial energy of Fe3C is known to be 0.71 J/m², and the molar volume of Fe is 23.4×10^-6 m³/mol.", "answer": "Cr=C∞(1+(2×23.4×10^-6×0.71)/(8.314×900×100×10^-9))=3.36×10^-3(1+4.440×10^-9/100×10^-9)=3.509×10^-3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的参数（温度、半径、界面能、摩尔体积）和公式进行数值计算，最终得出一个具体的溶解度数值。答案展示了完整的计算过程和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及溶解度公式的应用、单位转换和数值计算，需要理解界面能、摩尔体积等概念的综合运用，但不需要复杂的推理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解溶解度公式、界面能概念、摩尔体积应用，并进行多步计算和单位转换。虽然题目提供了关键参数，但解题过程涉及多个物理量的综合运用和代数运算，对学生的概念理解和计算能力要求较高。", "convertible": true, "correct_option": "3.509×10^-3", "choice_question": "At 627°C (i.e., 900K), what is the solubility of Fe3C particles with a radius of 100nm in α-Fe? The interfacial energy of Fe3C is known to be 0.71 J/m², and the molar volume of Fe is 23.4×10^-6 m³/mol.", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format with the correct option being the calculated result.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.509×10^-3", "B": "4.217×10^-3", "C": "2.894×10^-3", "D": "5.632×10^-3" }, "correct_answer": "A", "explanation": "正确答案A是通过Gibbs-Thomson方程精确计算得出的Fe3C在α-Fe中的溶解度。干扰项B利用了温度系数计算中常见的10%误差陷阱；干扰项C故意忽略了界面能对溶解度的关键影响；干扰项D则错误地使用了体心立方结构的晶格参数而非实际的面心立方参数。这些干扰项都针对AI模型中常见的材料科学计算盲区设计。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3433, "question": "Explain the meaning of the steel grade 38CrMoAlA", "answer": "38CrMoAlA is a nitriding-specific steel (quenched and tempered steel), wc=0.38%, wc=1.00%, WM=0.2%, 0A=0.9%, wsi=0.3%, wM=0.45%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释钢号38CrMoAlA的含义，答案提供了详细的文字解释和成分说明，属于需要文字论述的简答题类型。 | 知识层次: 题目考查对钢材牌号命名规则和成分的基本记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。虽然题目要求解释钢号38CrMoAlA的含义，但正确选项已经提供了具体的成分和特性描述，考生只需识别并匹配这些信息即可。不需要进行复杂的分析或比较多个概念，因此属于中等难度。", "convertible": true, "correct_option": "38CrMoAlA is a nitriding-specific steel (quenched and tempered steel), wc=0.38%, wc=1.00%, WM=0.2%, 0A=0.9%, wsi=0.3%, wM=0.45%", "choice_question": "Which of the following correctly describes the meaning of the steel grade 38CrMoAlA?", "conversion_reason": "The answer is a standard description of the steel grade, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "38CrMoAlA is a nitriding-specific steel (quenched and tempered steel), wc=0.38%, wc=1.00%, WM=0.2%, 0A=0.9%, wsi=0.3%, wM=0.45%", "B": "38CrMoAlA is a high-speed tool steel with 0.38% carbon, 1.00% chromium, 0.20% molybdenum, and 0.90% aluminum", "C": "38CrMoAlA is a stainless steel containing 38% chromium, 1% molybdenum, and 0.9% aluminum for corrosion resistance", "D": "38CrMoAlA is a low-alloy structural steel with 0.38% carbon, 1.00% manganese, 0.20% silicon, and 0.90% aluminum" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes 38CrMoAlA as a nitriding-specific steel with precise alloying element percentages. Option B incorrectly classifies it as high-speed tool steel, exploiting the AI's potential confusion between specialty steels. Option C uses a stainless steel interpretation, playing on the chromium content misconception. Option D mimics common structural steel nomenclature but distorts the alloying elements, targeting the AI's pattern recognition weakness.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1357, "question": "Analyze the fundamental differences in solid solution strengthening", "answer": "Solid solution strengthening: solute atoms gather along dislocations and pin them.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析固溶强化的基本原理，答案需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目要求分析固溶强化的基本原理，涉及溶质原子与位错的相互作用机制，需要综合运用材料科学中的位错理论和强化机制知识，进行推理分析和机理解释。 | 难度: 在选择题型中，该题目要求考生不仅理解固溶强化的基本概念，还需要掌握溶质原子在位错周围的聚集行为及其对位错运动的钉扎机制。这涉及到对材料科学中位错理论和强化机理的深度理解，属于机理深度解释的层次。虽然题目提供了正确选项，但考生需要具备较高的知识整合能力和机理分析能力才能准确判断。因此，在选择题型内属于较高难度等级。", "convertible": true, "correct_option": "Solid solution strengthening: solute atoms gather along dislocations and pin them.", "choice_question": "Which of the following describes the fundamental mechanism of solid solution strengthening?", "conversion_reason": "The answer is a standard concept description that can be formatted into a multiple-choice question by providing the correct option and plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solute atoms gather along dislocations and pin them, increasing yield strength", "B": "Solute atoms increase lattice vibration frequency, raising the Peierls stress", "C": "Solute atoms form covalent bonds with the matrix, enhancing overall stiffness", "D": "Solute atoms create local stress fields that directly oppose applied stresses" }, "correct_answer": "A", "explanation": { "correct_answer": "A is correct because solid solution strengthening fundamentally occurs when solute atoms segregate to dislocations, pinning them and requiring greater stress to move dislocations (yield strength increase).", "distractors": { "B": "This exploits confusion between thermal vibration effects and dislocation mechanics. While lattice vibrations do affect Peierls stress, this is not the primary mechanism of solid solution strengthening.", "C": "This traps AI by conflating solution strengthening with composite reinforcement. Most solute atoms don't form covalent bonds in metallic systems where this mechanism is dominant.", "D": "This sounds plausible but misrepresents the scale of effects. While stress fields exist, their direct opposition to applied stress is negligible compared to dislocation pinning effects." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2668, "question": "In indium with a tetragonal structure, the relative atomic mass A_r=114.82, atomic radius r=0.1625 nm, lattice constants a=0.3252 nm, c=0.4946 nm, and density ρ=7.286 g/cm³. How many atoms are there in the unit cell of In?", "answer": "n=(ρa²c×N_A)/A_r=(7.286×(3.252×10^-8)^2×(4.946×10^-8)×6.023×10^23)/114.82=1.9991≈2. Therefore, there are 2 atoms in the unit cell of In.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定单位晶胞中的原子数量，答案涉及具体的数学运算和单位转换。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过给定的密度、晶格常数和相对原子质量等参数，直接套用公式计算单位晶胞中的原子数。虽然需要理解相关概念和公式，但思维过程较为直接，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然涉及密度、晶格常数和原子质量等多个参数，但解题步骤明确且直接，只需套用单一公式（单位晶胞原子数计算公式）并进行简单代数运算即可得出答案。不需要复杂的逻辑推理或多步骤推导，符合选择题型中等级2的难度标准。", "convertible": true, "correct_option": "2", "choice_question": "In indium with a tetragonal structure, the relative atomic mass A_r=114.82, atomic radius r=0.1625 nm, lattice constants a=0.3252 nm, c=0.4946 nm, and density ρ=7.286 g/cm³. How many atoms are there in the unit cell of In?", "conversion_reason": "The calculation yields a definite numerical answer (2), which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2", "B": "选项D", "C": "选项B", "D": "选项C" }, "correct_answer": "A", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1611, "question": "What is the shape memory effect?", "answer": "When certain metal materials are deformed and then heated above a specific temperature, the deformed metal materials return to their pre-deformation shape. This phenomenon is called the shape memory effect.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"shape memory effect\"进行文字解释和论述，答案提供了详细的定义和现象描述，符合简答题的特征。 | 知识层次: 题目考查形状记忆效应的基本定义和现象描述，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对形状记忆效应基本定义的记忆，无需解释或分析复杂概念体系。正确选项直接给出了定义，属于基础概念记忆层次，符合等级1的难度标准。", "convertible": true, "correct_option": "When certain metal materials are deformed and then heated above a specific temperature, the deformed metal materials return to their pre-deformation shape. This phenomenon is called the shape memory effect.", "choice_question": "Which of the following best describes the shape memory effect?", "conversion_reason": "The answer is a standard definition of the shape memory effect, which can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When certain metal materials are deformed and then heated above a specific temperature, the deformed metal materials return to their pre-deformation shape", "B": "The ability of a material to recover its original shape after plastic deformation when stress is removed, due to reversible phase transformations", "C": "A phenomenon where polymers regain their original shape upon heating due to entropic elasticity and crosslinking", "D": "The spontaneous return to original shape in metallic alloys caused by dislocation movement and twinning mechanisms" }, "correct_answer": "A", "explanation": "Option A correctly describes the shape memory effect in shape memory alloys, which involves a temperature-induced phase transformation. Option B confuses shape memory effect with superelasticity (another property of SMAs). Option C describes polymer shape memory effect which is fundamentally different from metallic SMAs. Option D incorrectly attributes the effect to dislocation mechanisms rather than martensitic transformation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 435, "question": "Non-spontaneous nucleation still requires structural fluctuations, compositional fluctuations, and energy fluctuations.", "answer": "(√)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述句，要求判断其正确性（用√表示正确），符合判断题的特征 | 知识层次: 题目考查对非自发成核所需条件的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅要求判断一个简单陈述的正确性，涉及的是基础概念记忆层次的知识点（非自发形核的基本要求），无需复杂分析或推理。学生只需回忆相关定义即可作答，属于选择题型中最简单的难度等级。", "convertible": true, "correct_option": "(√)", "choice_question": "Non-spontaneous nucleation still requires structural fluctuations, compositional fluctuations, and energy fluctuations.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All phase transformations in metallic systems require nucleation sites to initiate.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because some phase transformations like spinodal decomposition occur without nucleation through continuous composition fluctuations. The absolute term 'all' makes this statement incorrect, though nucleation is indeed required for most conventional phase transformations. This tests understanding of different transformation mechanisms beyond classical nucleation theory.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 694, "question": "Sintering is a process that involves various physical and chemical changes", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（以×表示错误），符合判断题的特征 | 知识层次: 题目考查对烧结过程的基本概念的理解和记忆，属于基础概念层次。 | 难度: 该题目属于基础概念正误判断题，仅需记忆烧结过程的基本定义即可判断正误，无需深入理解或分析多个概念，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "×", "choice_question": "Sintering is a process that involves various physical and chemical changes", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials will exhibit piezoelectric properties when subjected to mechanical stress.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because only certain non-centrosymmetric crystalline ceramics exhibit piezoelectricity. The statement incorrectly generalizes this property to all ceramic materials, which is a common misconception. Many ceramics like alumina or zirconia do not show piezoelectric behavior due to their symmetric crystal structures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 502, "question": "Configuration of polymer chains", "answer": "Configuration of polymer chains: The spatial geometric arrangement of atoms in polymers fixed by chemical bonds.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Configuration of polymer chains\"进行文字解释和论述，答案提供了概念的定义和说明，符合简答题的特征 | 知识层次: 题目考查聚合物链构型的定义，属于基础概念的记忆和理解，不涉及应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别聚合物链构型的定义，属于基础概念的直接回忆。题目没有涉及复杂的概念体系或需要多步骤的分析过程，因此属于最低难度等级。", "convertible": true, "correct_option": "The spatial geometric arrangement of atoms in polymers fixed by chemical bonds.", "choice_question": "Which of the following best describes the configuration of polymer chains?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting the definition as the correct option among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The spatial geometric arrangement of atoms in polymers fixed by chemical bonds", "B": "The temporary physical entanglement of polymer chains under mechanical stress", "C": "The average molecular weight distribution of polymer chains in solution", "D": "The dynamic folding pattern of polymer chains determined by secondary interactions" }, "correct_answer": "A", "explanation": "The correct answer is A because polymer configuration specifically refers to the permanent spatial arrangement of atoms fixed by covalent bonds, which distinguishes it from temporary physical states. Option B exploits cognitive bias by describing a physical phenomenon (entanglement) that is often confused with chemical structure. Option C is a professional intuition trap, using a related but distinct polymer characteristic (molecular weight). Option D is a multi-level verification trap, mixing configuration with conformation (which involves secondary interactions).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2040, "question": "What are the main bonding types in ceramic materials?", "answer": "The main bonding types in ceramic materials are ionic bonds and covalent bonds.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释陶瓷材料中的主要键合类型，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查陶瓷材料中主要键合类型的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目仅要求记忆陶瓷材料的主要键合类型（离子键和共价键），属于基础概念记忆层次。题目不涉及概念解释或复杂体系阐述，仅需直接回忆定义性知识，因此在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "ionic bonds and covalent bonds", "choice_question": "What are the main bonding types in ceramic materials?", "conversion_reason": "The answer is a standard terminology that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ionic bonds and covalent bonds", "B": "metallic bonds and hydrogen bonds", "C": "covalent bonds and van der Waals forces", "D": "ionic bonds and metallic bonds" }, "correct_answer": "A", "explanation": "The correct answer is A because ceramic materials are primarily characterized by strong ionic and covalent bonding, which give them high melting points and hardness. Option B is incorrect as metallic bonds are characteristic of metals, not ceramics, and hydrogen bonds are too weak to be considered main bonding types in ceramics. Option C is misleading because while covalent bonds are correct, van der Waals forces are secondary interactions, not primary bonding types in ceramics. Option D is incorrect because metallic bonds do not occur in ceramics, exploiting the common misconception that ceramics may share some properties with metals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4070, "question": "[e] Copper is relatively resistant to corrosion by neutral and even mildly basic water, making it useful for freshwater plumbing applications.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（铜在中性和弱碱性水中相对耐腐蚀），并要求判断其正确性（答案T表示正确），符合判断题的特征。 | 知识层次: 题目考查对铜在特定环境下的耐腐蚀性能这一基础概念的记忆和理解，属于材料科学中的基本原理记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅要求考生记忆铜在中性和弱碱性水中的耐腐蚀性这一基础事实，无需进行概念理解或复杂分析。正确选项直接对应基础概念记忆层次的知识点，解题步骤简单直接。", "convertible": true, "correct_option": "T", "choice_question": "[e] Copper is relatively resistant to corrosion by neutral and even mildly basic water, making it useful for freshwater plumbing applications.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "Copper is completely immune to corrosion in all types of freshwater environments, including those with high oxygen content.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While copper is indeed resistant to corrosion in neutral and mildly basic water, the statement is incorrect because it uses absolute terms ('completely immune', 'all types'). Copper can corrode in oxygen-rich freshwater environments through oxidation processes. The original correct statement was more carefully worded to specify 'relatively resistant' and 'neutral/mildly basic' conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3511, "question": "In the graphitization process of cast iron, if the first stage is completely graphitized and the second stage is not graphitized, what type of cast iron structure is obtained?", "answer": "P+G (graphite)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要解释在铸铁石墨化过程中特定条件下的结构类型，答案以文字形式给出（P+G (graphite)），属于简答题类型 | 知识层次: 题目考查对铸铁石墨化过程的基础概念记忆，只需识别石墨化不同阶段的结果对应的铸铁结构类型，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅考察对铸铁石墨化过程基础概念的记忆，即知道第一阶段完全石墨化和第二阶段未石墨化会得到P+G（石墨）结构的铸铁。不需要解释或分析复杂概念体系，只需识别正确选项即可。", "convertible": true, "correct_option": "P+G (graphite)", "choice_question": "In the graphitization process of cast iron, if the first stage is completely graphitized and the second stage is not graphitized, what type of cast iron structure is obtained?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "P+G (graphite)", "B": "F+P (ferrite + pearlite)", "C": "P (pearlite)", "D": "F+G (ferrite + graphite)" }, "correct_answer": "A", "explanation": "The correct answer is A because when only the first stage of graphitization is complete, it results in pearlite matrix with graphite (P+G). Option B is incorrect as it describes a non-graphitized structure. Option C is wrong because it ignores the graphite formation. Option D is a plausible trap as it correctly includes graphite but incorrectly assumes full ferrite transformation without second stage graphitization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 411, "question": "Constitutional supercooling", "answer": "Constitutional supercooling: During crystallization, the redistribution of solid and liquid phase compositions leads to the formation of a supercooled region in the liquid phase near the solid-liquid interface. This phenomenon is called constitutional supercooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Constitutional supercooling\"这一现象进行文字解释和论述，答案提供了详细的定义和过程描述，符合简答题的特征。 | 知识层次: 题目考查对\"Constitutional supercooling\"这一基本概念的定义和现象描述，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于概念解释和描述难度。虽然涉及基础概念记忆，但需要理解并描述\"Constitutional supercooling\"这一现象的形成过程和基本原理，比单纯记忆定义要复杂一些，但不需要进行多个概念的比较分析或复杂体系阐述。", "convertible": true, "correct_option": "Constitutional supercooling: During crystallization, the redistribution of solid and liquid phase compositions leads to the formation of a supercooled region in the liquid phase near the solid-liquid interface. This phenomenon is called constitutional supercooling.", "choice_question": "Which of the following correctly describes constitutional supercooling?", "conversion_reason": "The answer is a standard definition of a scientific term, which can be converted into a multiple-choice question format by providing the correct definition as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Constitutional supercooling occurs when solute redistribution during solidification creates a compositionally-depleted liquid zone with lower freezing point than the bulk liquid", "B": "Constitutional supercooling is caused by rapid cooling rates that prevent atomic diffusion at the solid-liquid interface", "C": "Constitutional supercooling refers to the temperature fluctuation in molten metals due to convection currents during casting", "D": "Constitutional supercooling describes the phenomenon where impurities preferentially segregate to grain boundaries during solidification" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the solute redistribution mechanism and resulting freezing point depression that defines constitutional supercooling. Option B incorrectly attributes it to cooling rates and diffusion limitations, which is a common confusion with thermal supercooling. Option C introduces a red herring about convection currents, exploiting the 'supercooling' naming similarity. Option D describes segregation behavior but misses the key interfacial supercooling aspect, playing on grain boundary segregation misconceptions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 753, "question": "Methods to prevent secondary recrystallization", "answer": "Methods to prevent secondary recrystallization: control sintering temperature, sintering time, control the uniformity of raw material particle size, and introduce sintering additives.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求列举防止二次再结晶的方法，答案以文字解释和论述的形式给出，没有选项、判断或计算要求。 | 知识层次: 题目要求列举防止二次再结晶的方法，涉及对烧结温度、时间、原料颗粒均匀性和烧结添加剂等多个因素的综合考虑，需要将多个概念关联起来进行分析和应用，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及防止二次再结晶的方法，要求考生掌握烧结温度、烧结时间、原料颗粒均匀性和烧结添加剂等多个因素的综合影响。虽然不需要复杂的计算，但需要对材料科学中的相关概念有较深的理解和关联能力。", "convertible": true, "correct_option": "control sintering temperature, sintering time, control the uniformity of raw material particle size, and introduce sintering additives", "choice_question": "Which of the following are methods to prevent secondary recrystallization?", "conversion_reason": "The answer is a standard list of methods, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "control sintering temperature", "B": "increase cooling rate during solidification", "C": "apply external magnetic field during annealing", "D": "use single crystal precursor materials" }, "correct_answer": "A", "explanation": "The correct answer is A because controlling sintering temperature directly affects grain boundary mobility and prevents abnormal grain growth. Option B exploits cognitive bias by suggesting a common metallurgical practice (controlling cooling rate) that doesn't address recrystallization. Option C is a professional intuition trap, using a real material processing technique (magnetic annealing) that's irrelevant to recrystallization prevention. Option D is a multi-level verification trap, as single crystal precursors seem plausible but don't prevent secondary recrystallization in polycrystalline systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2143, "question": "Point out the errors in the following concept: (1) If there is no diffusion flow in a solid, it means that atoms are not diffusing.", "answer": "Even if there is no macroscopic diffusion flow in a solid, diffusion still occurs due to the migration jumps of atomic thermal vibrations. Self-diffusion in pure substances is a typical example.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求指出概念中的错误并进行解释，答案通过文字论述说明了即使没有宏观扩散流，扩散仍然发生的原因，符合简答题的特征。 | 知识层次: 题目要求分析并指出概念中的错误，需要理解扩散现象的微观机制（原子热振动迁移）与宏观表现（扩散流）之间的关系，并进行推理分析。这涉及对扩散原理的深度理解和综合运用，超出了简单记忆或应用的范畴。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求理解扩散的基本概念，还需要深入掌握扩散的微观机理（如原子热振动迁移跳跃）和宏观表现（无净扩散流）之间的关系。正确选项涉及对自扩散现象的机理解释，这需要学生具备将微观原子行为与宏观现象联系起来的能力，属于复杂分析层次的知识运用。", "convertible": true, "correct_option": "Even if there is no macroscopic diffusion flow in a solid, diffusion still occurs due to the migration jumps of atomic thermal vibrations. Self-diffusion in pure substances is a typical example.", "choice_question": "Which of the following correctly points out the errors in the concept: 'If there is no diffusion flow in a solid, it means that atoms are not diffusing.'?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question format because the answer is a standard explanation that can be presented as one of the options. The question can be rephrased to ask for the correct identification of the error in the given concept.", "perplexity": { "has_perplexity": false, "perplexity_type": "None", "perplexity_level": "None", "perplexity_reason": "The question is clear and provides all necessary information for a materials science graduate student to answer it. The concept being evaluated is well-defined, and the correct option explains the error in the given concept without requiring additional context or data.", "missing_info": "None" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The statement is correct because no diffusion flow directly implies no atomic movement", "B": "The statement is incorrect because diffusion can occur through vacancy mechanisms without net flow", "C": "The statement is incorrect because grain boundary diffusion always creates measurable flow", "D": "The statement is correct because Fick's first law requires concentration gradient for any diffusion" }, "correct_answer": "B", "explanation": "The correct answer is B because self-diffusion in pure materials occurs through random atomic jumps (vacancy mechanism) without creating net diffusion flow. Option A exploits the common misconception that diffusion requires observable mass transport. Option C creates a grain boundary red herring that seems plausible but is irrelevant to the core concept. Option D misapplies Fick's first law which describes net flow, not individual atomic movements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3059, "question": "What material is suitable for a thermocouple sheath? Options: A.Polyvinyl chloride B.2Cr13 C.High-temperature ceramics D.Manganese brass", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择适合用于热电偶护套的材料，且提供了四个具体选项和唯一正确答案 | 知识层次: 题目考查对热电偶套管材料选择的基本概念记忆，只需知道高温陶瓷具有耐高温特性这一基础知识即可作答，无需复杂分析或计算。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别和回忆热电偶护套材料的合适选项。选项C（高温陶瓷）是热电偶护套的常见材料，属于直接记忆性知识，无需复杂辨析或深度理解。因此，该题目在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "C.High-temperature ceramics", "choice_question": "What material is suitable for a thermocouple sheath?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polycrystalline alumina with 5% porosity", "B": "Hot-pressed silicon nitride with 99% density", "C": "Reaction-bonded silicon carbide with 15% free silicon", "D": "Yttria-stabilized zirconia with 3% alumina dopant" }, "correct_answer": "B", "explanation": "Hot-pressed silicon nitride (B) is the correct choice due to its exceptional thermal shock resistance and mechanical strength at high temperatures. The 99% density ensures minimal porosity for gas tightness. Polycrystalline alumina (A) is a trap for those focusing only on chemical inertness but ignoring thermal shock limitations. Reaction-bonded SiC (C) exploits the common misconception that all SiC forms are equally suitable, while the free silicon content makes it unsuitable. Yttria-stabilized zirconia (D) plays on its fame in fuel cells, but its phase stability issues above 1200°C make it a poor sheath material.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4852, "question": "Consider a parallel-plate capacitor having an area of 3225 mm2 (5 in.2), a plate separation of 1mm (0.04 in.), and a material having a dielectric constant of 3.5 positioned between the plates. What is the capacitance of this capacitor?", "answer": "the capacitance of this capacitor is 100 pf.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（电容公式）来求解电容器的电容值，答案是一个具体的数值结果（100 pf），属于典型的计算题特征。 | 知识层次: 题目涉及基本的电容计算公式应用（C = εA/d），只需要直接套用公式并进行简单的数值计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算平行板电容器的电容，只需直接套用平行板电容公式C = ε₀εᵣA/d，其中所有参数（面积A、板间距d、介电常数εᵣ）都已给出，且不需要单位换算（题目已提供统一单位）。解题步骤简单直接，属于最基本的知识应用层次。", "convertible": true, "correct_option": "100 pf", "choice_question": "Consider a parallel-plate capacitor having an area of 3225 mm2 (5 in.2), a plate separation of 1mm (0.04 in.), and a material having a dielectric constant of 3.5 positioned between the plates. What is the capacitance of this capacitor?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "100 pF", "B": "10 nF", "C": "1 μF", "D": "0.1 pF" }, "correct_answer": "A", "explanation": "The correct answer is A (100 pF) calculated using the parallel-plate capacitor formula C = ε₀εᵣA/d, where ε₀ is vacuum permittivity (8.854×10⁻¹² F/m), εᵣ is 3.5, A is 3225 mm² (3.225×10⁻³ m²), and d is 1 mm (0.001 m). Option B (10 nF) is a common mistake from misplacing the decimal point. Option C (1 μF) appeals to intuition from commercial capacitors but is orders of magnitude too large. Option D (0.1 pF) traps those who confuse mm² with m² in area calculation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3711, "question": "A force of 100000 N is applied to a 10mm × 20mm iron bar having a yield strength of 400 MPa. Determine whether the bar will plastically deform.", "answer": "the bar will plastically deform because the applied stress of 500 MPa exceeds the yield strength of 400 MPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要通过计算施加的应力（force/area）并与屈服强度比较来判断是否发生塑性变形。答案中给出了具体的计算过程和数值比较，符合计算题的特征。 | 知识层次: 题目涉及基本的应力计算和与屈服强度的比较，属于直接套用公式和简单计算的范畴，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，需要应用基本公式（应力=力/面积）进行简单计算，并将计算结果与材料的屈服强度直接比较。虽然涉及单位换算（mm²到m²），但步骤较为直接，属于等级2的简单公式应用计算难度。", "convertible": true, "correct_option": "the bar will plastically deform because the applied stress of 500 MPa exceeds the yield strength of 400 MPa", "choice_question": "A force of 100000 N is applied to a 10mm × 20mm iron bar having a yield strength of 400 MPa. What will happen to the bar?", "conversion_reason": "The original question is a calculation problem with a definitive answer that can be converted into a multiple-choice format. The correct option is derived from the provided answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The bar will fracture immediately due to stress concentration at the edges", "B": "The bar will undergo elastic deformation only, as the stress is below the ultimate tensile strength", "C": "The bar will plastically deform because the applied stress of 500 MPa exceeds the yield strength of 400 MPa", "D": "The bar will exhibit creep behavior due to the high stress level" }, "correct_answer": "C", "explanation": "The correct answer is C because the applied stress (100000N/(10mm×20mm)=500MPa) exceeds the yield strength. Option A exploits the common misconception about edge effects in small samples. Option B uses the ultimate tensile strength (typically higher than yield) as a distraction. Option D introduces creep which requires sustained loading at high temperatures, creating a multi-parameter verification trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3610, "question": "Which, if any, of these planes is close packed in BCC lithium?", "answer": "there is no close-packed plane in bcc structures.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目实际上是在判断\"BCC锂中是否存在密排面\"这一陈述的正确性，答案为明确的判断性陈述（不存在）。虽然以疑问句形式呈现，但本质是判断一个事实陈述的真伪。 | 知识层次: 题目考查对BCC晶体结构中密排面存在与否的基础概念记忆和理解，属于晶体学的基本知识点，不需要复杂的分析或计算。 | 难度: 该题目属于基础概念记忆层次，仅需判断BCC结构中是否存在密排面这一基本事实。选择题型中只需识别正确选项，无需复杂推理或概念整合，属于最基础的正误判断难度等级。", "convertible": true, "correct_option": "there is no close-packed plane in bcc structures.", "choice_question": "Which, if any, of these planes is close packed in BCC lithium?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In BCC crystal structures, the {110} planes are close-packed.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "BCC structures do not have truly close-packed planes. While the {110} planes have the highest planar density in BCC, they are not close-packed like the {111} planes in FCC or the (0001) planes in HCP. This is a common misconception because the {110} planes are the most densely packed in BCC, but they don't meet the strict geometrical requirements of close-packing where spheres cover 74% of the plane area.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4052, "question": "Which of the following are preferred for semiconducting devices?(a) Single crystals(b) Polycrystalline materials", "answer": "Single crystals are preferred for semiconducting devices because grain boundaries are deleterious to the performance of electronic phenomena.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从两个选项(a)和(b)中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对半导体器件材料选择的基本概念记忆和理解，涉及单晶和多晶材料的性能差异这一基本原理。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然涉及半导体材料的基础概念，但只需要理解单晶和多晶材料在半导体器件中的性能差异，无需复杂的分析或计算。正确选项直接给出了关键原因（晶界对电子现象性能有害），属于概念理解和简单辨析的层次。", "convertible": true, "correct_option": "Single crystals", "choice_question": "Which of the following are preferred for semiconducting devices?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly identifies one correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Single crystals with controlled dopant segregation", "B": "Polycrystalline materials with optimized grain boundary passivation", "C": "Amorphous thin films with precisely engineered defect states", "D": "Nanocrystalline composites with quantum confinement effects" }, "correct_answer": "A", "explanation": "Single crystals are preferred for semiconducting devices due to their uniform electronic properties and absence of grain boundaries that can scatter charge carriers. Option B is a cognitive bias trap - while grain boundary passivation improves polycrystalline materials, they still can't match single crystal performance. Option C exploits the 'defect engineering' trend but amorphous materials lack the periodic potential required for most semiconductor devices. Option D uses cutting-edge nanotechnology concepts that are actually detrimental to conventional semiconductor operation by introducing uncontrolled quantum effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 441, "question": "During diffusion, solute atoms always migrate from high concentration to low concentration.", "answer": "(×)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其对错（答案给出的是×表示错误），符合判断题的特征 | 知识层次: 题目考查扩散过程中溶质原子迁移方向的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于非常基础的概念正误判断。只需要记忆扩散过程中溶质原子的迁移方向这一基本原理即可作答，无需深入理解或分析多个概念。题目直接考察对基础定义的记忆，属于选择题型中最简单的难度等级。", "convertible": true, "correct_option": "(×)", "choice_question": "During diffusion, solute atoms always migrate from high concentration to low concentration.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all diffusion processes, the net flux of solute atoms is always from regions of higher chemical potential to lower chemical potential.", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "While concentration gradient is the most common driving force for diffusion, the fundamental driving force is actually the chemical potential gradient. Even in cases like uphill diffusion where atoms appear to move against the concentration gradient (e.g., in spinodal decomposition), they are still moving down the chemical potential gradient. This subtle distinction challenges the common misconception that diffusion is solely about concentration gradients.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 759, "question": "What is intrinsic diffusion?", "answer": "Intrinsic diffusion: refers to the migration phenomenon caused by vacancies originating from the intrinsic thermal defects of the crystal. The activation energy of intrinsic diffusion consists of two parts: the vacancy formation energy and the particle migration energy. At high temperatures, intrinsic diffusion predominates.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"intrinsic diffusion\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即intrinsic diffusion的定义和基本原理，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度。题目要求考生理解并记忆\"intrinsic diffusion\"的定义及其关键组成部分（空位形成能和粒子迁移能），并知道其在高温条件下的主导性。虽然涉及两个能量概念，但整体仍属于单一概念的解释层面，不需要进行多个概念的比较或复杂分析。", "convertible": true, "correct_option": "Intrinsic diffusion: refers to the migration phenomenon caused by vacancies originating from the intrinsic thermal defects of the crystal. The activation energy of intrinsic diffusion consists of two parts: the vacancy formation energy and the particle migration energy. At high temperatures, intrinsic diffusion predominates.", "choice_question": "Which of the following best describes intrinsic diffusion?", "conversion_reason": "The answer is a standard definition of a scientific term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diffusion driven by thermal vacancies in a perfect crystal lattice, requiring both vacancy formation and migration energies", "B": "Atomic movement caused by external impurities creating excess vacancies in the lattice", "C": "Grain boundary diffusion that dominates at lower temperatures due to reduced activation energy", "D": "Stress-induced diffusion where lattice defects migrate under applied mechanical load" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes intrinsic diffusion as migration due to thermal vacancies in perfect crystals, involving both vacancy formation and migration energies. Option B incorrectly describes extrinsic diffusion caused by impurities. Option C is a common confusion with grain boundary diffusion which is a separate mechanism. Option D describes stress-induced diffusion, another distinct phenomenon. Advanced AIs may mistake B for intrinsic diffusion due to the 'vacancy' keyword, or select C due to temperature-dependency reasoning errors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1130, "question": "In terms of lattice constant, what is the atomic diameter in a BCC crystal structure?", "answer": "The close-packed direction in BCC structure is [111]. In the unit cell, there are two atoms along the [111] direction, so the atomic diameter is (√3/2)a.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算确定BCC晶体结构中的原子直径，涉及晶格常数和几何关系的数值计算，答案给出了具体的计算公式和结果。 | 知识层次: 题目需要理解BCC晶体结构的特点，识别密排方向[111]，并应用几何关系（√3/2）a进行多步计算，涉及概念关联和综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构的基本概念，掌握[111]方向的原子排列方式，并进行多步计算（包括对角线长度计算和原子直径推导）。虽然不涉及复杂变量，但需要将晶体几何知识与数学计算相结合，属于综合性计算问题。", "convertible": true, "correct_option": "(√3/2)a", "choice_question": "In terms of lattice constant, what is the atomic diameter in a BCC crystal structure?", "conversion_reason": "The answer is a specific mathematical expression, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(√3/2)a", "B": "a/2", "C": "a/√2", "D": "(√3/4)a" }, "correct_answer": "A", "explanation": "The correct answer is A because in a BCC structure, the atomic diameter spans the body diagonal where atoms touch, which is √3a/2. Option B is the nearest neighbor distance, not the atomic diameter. Option C mimics FCC calculations to exploit structural confusion. Option D is half the correct value to catch unit cell vs atomic dimension miscalculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3472, "question": "How are special property steels further classified?", "answer": "Special property steels are divided into: stainless steel, heat-resistant steel, and wear-resistant steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对特殊性能钢的分类进行文字解释和论述，答案提供了具体的分类说明，符合简答题的特征。 | 知识层次: 题目考查特殊性能钢的分类，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆特殊性能钢的基本分类（不锈钢、耐热钢、耐磨钢），属于最基础的定义简答层面。题目不涉及概念解释或复杂体系阐述，仅需直接回忆教材中的分类标准即可作答，因此属于难度等级1。", "convertible": true, "correct_option": "stainless steel, heat-resistant steel, and wear-resistant steel", "choice_question": "How are special property steels further classified?", "conversion_reason": "The answer is a standard classification of special property steels, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "stainless steel, heat-resistant steel, and wear-resistant steel", "B": "high-strength steel, tool steel, and structural steel", "C": "ferritic steel, austenitic steel, and martensitic steel", "D": "carbon steel, alloy steel, and microalloyed steel" }, "correct_answer": "A", "explanation": "The correct classification is based on special properties rather than strength levels (B), microstructure (C), or composition (D). Option B confuses by listing strength-based categories, Option C uses microstructure classifications common in stainless steels but not special property steels, and Option D presents composition-based categories that overlap with but don't specifically denote special properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3884, "question": "Materials Science and Engineering is the study of material behavior & performance and how this is simultaneously related to structure, properties, and processing. Which of the following is the best example of material structure? (a) Single-phase (b) Elastic Modulus (c) Sintering (d) Magnetic Permeability (e) Brittle", "answer": "(a)Single-phase", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择最佳答案，符合选择题的特征 | 知识层次: 题目考查对材料结构这一基础概念的记忆和理解，要求从选项中识别出最能代表材料结构的例子，属于基础概念记忆性知识。 | 难度: 在选择题型中，此题属于简单概念识别，直接记忆的题目。题目要求识别\"material structure\"的最佳例子，正确选项(a)Single-phase是材料结构的基础概念之一，无需复杂理解或分析，只需记忆相关定义即可作答。", "convertible": true, "correct_option": "Single-phase", "choice_question": "Materials Science and Engineering is the study of material behavior & performance and how this is simultaneously related to structure, properties, and processing. Which of the following is the best example of material structure?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship in nanocrystalline materials with grain sizes below 10nm", "B": "The inverse Hall-Petch effect observed in ultra-fine grained metals", "C": "The constant yield strength plateau in severely deformed materials", "D": "The linear proportionality between hardness and dislocation density" }, "correct_answer": "B", "explanation": "The inverse Hall-Petch effect is the correct answer as it represents a genuine deviation from classical strengthening mechanisms at very small grain sizes. Option A is a cognitive bias trap - while the Hall-Petch relationship is fundamental, it breaks down below critical grain sizes. Option C exploits intuitive expectations of continuous strengthening, ignoring saturation effects. Option D is a multi-level trap combining correct concepts (hardness-dislocation relationship) with incorrect linear proportionality assumption.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3131, "question": "Explain the basic concept and terminology: Modification treatment", "answer": "Modification treatment: Before casting metal or alloy, adding certain solid-phase substances that can promote heterogeneous nucleation or hinder the growth of crystal nuclei into the molten metal to refine the grains of the casting is called modification treatment.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释基本概念和术语，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，要求解释\"Modification treatment\"的定义和基本原理，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求解释\"Modification treatment\"的基本概念和术语，正确选项提供了明确的定义和基本原理，但不需要进行复杂的概念体系阐述或多概念比较分析。该题目主要考察对单一概念的记忆和理解，符合选择题型中中等难度的要求。", "convertible": true, "correct_option": "Modification treatment: Before casting metal or alloy, adding certain solid-phase substances that can promote heterogeneous nucleation or hinder the growth of crystal nuclei into the molten metal to refine the grains of the casting is called modification treatment.", "choice_question": "Which of the following best describes the concept of modification treatment?", "conversion_reason": "The answer is a standard definition of a technical term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Adding solid-phase substances to molten metal before casting to promote heterogeneous nucleation and refine grains", "B": "Heat treatment process to modify the surface hardness of cast alloys through rapid quenching", "C": "Electrochemical treatment to alter the surface composition of metals by ion implantation", "D": "Mechanical deformation process to refine grain structure through severe plastic deformation" }, "correct_answer": "A", "explanation": "The correct answer is A because modification treatment specifically refers to grain refinement through nucleation agents added before casting. Option B is a heat treatment process unrelated to casting modification. Option C describes a surface modification technique, not bulk grain refinement. Option D refers to grain refinement through mechanical means rather than nucleation control during solidification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3011, "question": "To which category of compounds do nylon and polysulfone belong? Options: A. Carbon-chain organic polymers B. Heterochain organic polymers C. Elemental organic compounds D. Inorganic polymers", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从四个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对聚合物分类的基本概念记忆，只需要知道尼龙和聚砜属于杂链有机聚合物即可回答，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（有机聚合物的分类），但需要学生理解并区分\"碳链有机聚合物\"和\"杂链有机聚合物\"这两个概念。学生需要知道尼龙和聚砜的分子结构特点（含有杂原子），才能正确选择\"杂链有机聚合物\"这个选项。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析过程（等级3）。", "convertible": true, "correct_option": "B. Heterochain organic polymers", "choice_question": "To which category of compounds do nylon and polysulfone belong?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Carbon-chain organic polymers", "B": "Heterochain organic polymers", "C": "Elemental organic compounds", "D": "Inorganic polymers" }, "correct_answer": "B", "explanation": "Nylon and polysulfone are heterochain organic polymers because their polymer chains contain atoms other than carbon (such as nitrogen, oxygen, and sulfur) in the backbone. Option A is incorrect as it describes polymers with only carbon in the backbone. Option C is misleading as it suggests simple elemental compounds rather than complex polymers. Option D exploits the common misconception that synthetic polymers might be inorganic due to their industrial production methods.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2278, "question": "Calculate the critical length Lc of β-SiC whiskers, given a diameter of 0.5μm, tensile strength of 70000MPa, and interfacial shear strength τy approximated by the matrix yield strength of 76MPa.", "answer": "For β-SiC whiskers, the critical length Lc = (0.5×10^-6 × 70000) / (2 × 38) = 460.5×10^-6 m = 460.5μm. Since the actual length of 70μm is less than Lc, the fibers do not achieve the maximum strengthening effect.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的参数（直径、拉伸强度、界面剪切强度）进行数值计算，应用公式求解临界长度Lc，答案也是具体的数值计算结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和公式应用，需要理解临界长度的概念并将其与材料参数（直径、拉伸强度、界面剪切强度）关联起来进行计算。虽然计算过程相对直接，但需要对材料性能参数的综合理解和应用。 | 难度: 在选择题中属于中等偏上难度，需要理解临界长度的计算公式，并进行多步单位换算和数值计算。题目涉及材料力学性能参数的综合运用，要求考生能够正确代入公式并处理单位转换（MPa到Pa、μm到m），最后还需要对计算结果进行实际意义分析（比较实际长度与临界长度）。虽然题目提供了公式框架，但计算步骤和概念关联性较强，在选择题型中属于需要一定综合分析能力的题目。", "convertible": true, "correct_option": "460.5μm", "choice_question": "Calculate the critical length Lc of β-SiC whiskers, given a diameter of 0.5μm, tensile strength of 70000MPa, and interfacial shear strength τy approximated by the matrix yield strength of 76MPa. The critical length Lc is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "460.5μm", "B": "230.3μm", "C": "920.8μm", "D": "115.1μm" }, "correct_answer": "A", "explanation": "The critical length Lc is calculated using the formula Lc = (σf * d)/(2τy), where σf is the tensile strength, d is the diameter, and τy is the interfacial shear strength. Plugging in the given values: Lc = (70000MPa * 0.5μm)/(2 * 76MPa) = 460.5μm. Option B is half the correct value, exploiting the common error of forgetting to divide by 2 in the formula. Option C is double the correct value, targeting those who might mistakenly multiply by 2 instead of dividing. Option D is one-fourth the correct value, preying on those who might confuse diameter with radius in the calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2076, "question": "Point out the errors in the following concepts and correct them: (16) The microstructure morphology of a saturated aqueous solution of ammonium chloride and pure metal at the end of crystallization is the same, with the former exhibiting dendritic crystals and the latter also exhibiting dendritic crystals.", "answer": "The microstructure morphology at the end of crystallization is different; the former exhibits dendritic crystals (with water between the branches), while the latter exhibits individual (blocky) grains.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求指出并纠正概念中的错误，类似于判断陈述的对错并给出正确解释。答案形式是对原陈述的否定和修正，符合判断题的特征。 | 知识层次: 题目考查对结晶过程中微观结构形态的基础概念记忆和理解，涉及对饱和溶液和纯金属结晶形态差异的基本认识。 | 难度: 在选择题型中，该题目属于中等偏下难度。题目要求考生区分两种不同结晶过程的微观结构形态，需要理解饱和氯化铵水溶液和纯金属在结晶结束时的不同表现。虽然涉及基础概念记忆，但需要考生对结晶形态有清晰的理解，并能正确识别和纠正错误陈述。解题步骤相对简单，但需要准确的概念掌握。", "convertible": true, "correct_option": "The microstructure morphology at the end of crystallization is different; the former exhibits dendritic crystals (with water between the branches), while the latter exhibits individual (blocky) grains.", "choice_question": "Point out the errors in the following concepts and correct them: (16) The microstructure morphology of a saturated aqueous solution of ammonium chloride and pure metal at the end of crystallization is the same, with the former exhibiting dendritic crystals and the latter also exhibiting dendritic crystals.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All pure metals always exhibit dendritic crystal structures during solidification under any cooling conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While dendritic growth is common in pure metals during solidification, it is not universal. The crystal structure depends on cooling conditions - very slow cooling can produce equiaxed grains instead of dendrites. The use of 'all' and 'always' makes this statement incorrect. This tests understanding of solidification morphology dependence on processing conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2433, "question": "The diameter of polyester (PET) carpet fiber is 50 micrometers, immersed in a dye bath containing water, dye, and dye bags at boiling temperature. The diffusion coefficients of water, dye, and dye bags are 1.0×10^-12 m²/s, 1.0×10^-13 m²/s, and 1.0×10^-14 m²/s, respectively. Estimate the time required for water, dye, and dye bags to penetrate into the center of the fiber.", "answer": "Using the simple one-dimensional diffusion distance-time relationship l=√(2Dt) for approximate estimation, the penetration depth is 25 micrometers. The time required for water to penetrate into the fiber center is t=(25×10^-6)^2/(2×1.0×10^-12)=312.5 s; the time required for dye to penetrate into the fiber center is t=(25×10^-6)^2/(2×1.0×10^-13)=3125 s; the time required for dye bags to penetrate into the fiber center is t=(25×10^-6)^2/(2×1.0×10^-14)=31250 s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计水、染料和染料袋渗透到纤维中心所需的时间，答案给出了具体的计算过程和结果。 | 知识层次: 题目主要涉及基本公式（一维扩散距离-时间关系）的直接应用和简单计算，无需多步推理或综合分析，属于基础知识的直接运用。 | 难度: 在选择题型中，该题目仅需要直接套用一个基本公式（l=√(2Dt)）进行计算，解题步骤简单明确，无需组合多个公式或进行复杂分析。题目提供了所有必要参数，计算过程属于单一公式直接应用，符合等级1的难度标准。", "convertible": true, "correct_option": "Water: 312.5 s; Dye: 3125 s; Dye bags: 31250 s", "choice_question": "The diameter of polyester (PET) carpet fiber is 50 micrometers, immersed in a dye bath containing water, dye, and dye bags at boiling temperature. The diffusion coefficients of water, dye, and dye bags are 1.0×10^-12 m²/s, 1.0×10^-13 m²/s, and 1.0×10^-14 m²/s, respectively. Estimate the time required for water, dye, and dye bags to penetrate into the center of the fiber.", "conversion_reason": "The original question is a calculation problem with a specific and deterministic answer. It can be converted into a multiple-choice question by providing the correct answer as one of the options and possibly adding plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Water: 312.5 s; Dye: 3125 s; Dye bags: 31250 s", "B": "Water: 625 s; Dye: 6250 s; Dye bags: 62500 s", "C": "Water: 156.25 s; Dye: 1562.5 s; Dye bags: 15625 s", "D": "Water: 1250 s; Dye: 12500 s; Dye bags: 125000 s" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula t = r²/(4D), where r is the radius (25 micrometers) and D is the diffusion coefficient. The incorrect options are designed to exploit common calculation errors: B doubles the correct times (common factor error), C halves the times (radius/diameter confusion), and D multiplies by 4 (incorrect formula application).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4727, "question": "Determine the ASTM grain size number if 30 grains per square inch are measured at a magnification of 250 ×.", "answer": "the astm grain size number is 8.6.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定ASTM晶粒度数值，答案是一个具体的数值结果（8.6），符合计算题的特征。 | 知识层次: 题目涉及基本的ASTM晶粒度计算公式应用，仅需直接套用公式进行简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用ASTM grain size number的计算公式，但题目已经提供了所有必要的参数（30 grains per square inch和250× magnification），只需直接套用公式即可得出结果。解题步骤相对简单，不需要复杂的推理或多步骤计算，因此属于等级2难度。", "convertible": true, "correct_option": "8.6", "choice_question": "Determine the ASTM grain size number if 30 grains per square inch are measured at a magnification of 250 ×. The correct ASTM grain size number is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.6", "B": "7.3", "C": "9.1", "D": "6.8" }, "correct_answer": "A", "explanation": "The correct ASTM grain size number is calculated using the formula N = (n/250^2) * 2^(G-1), where N is the number of grains per square inch at 100x magnification, n is the observed count (30), and 250 is the magnification factor. Solving for G gives 8.6. Option B (7.3) is derived by incorrectly using linear magnification instead of area magnification. Option C (9.1) results from forgetting to square the magnification factor. Option D (6.8) is obtained by reversing the magnification correction (dividing by 250 instead of multiplying). These errors exploit common calculation mistakes in microscopy analysis.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1403, "question": "Determine whether the following statement is correct: The growth of recrystallization nuclei is accompanied by the movement of grain boundaries, so the driving force is grain boundary energy.", "answer": "Incorrect", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断陈述的对错，答案直接给出了\"Incorrect\"的判断结果，符合判断题的特征。 | 知识层次: 题目涉及再结晶核生长和晶界移动的驱动力的判断，需要理解再结晶过程中的能量变化和晶界行为，属于概念关联和综合分析的中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合分析再结晶核生长过程中的驱动力来源，并正确判断晶界能并非主要驱动力。题目涉及中等应用层次的知识点关联和多步概念判断，要求考生区分表面能、应变能和晶界能等不同驱动力的作用机制。", "convertible": true, "correct_option": "Incorrect", "choice_question": "Determine whether the following statement is correct: The growth of recrystallization nuclei is accompanied by the movement of grain boundaries, so the driving force is grain boundary energy.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The growth of recrystallization nuclei is accompanied by the movement of grain boundaries, so the driving force is grain boundary energy.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the growth of recrystallization nuclei does involve grain boundary movement, the primary driving force is actually the stored strain energy from prior deformation, not grain boundary energy. This is a common misconception where students may confuse the mechanism (boundary movement) with the actual driving force (stored energy). The grain boundary energy plays a secondary role in determining boundary mobility but isn't the main driving force for recrystallization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3912, "question": "Consider the ideal barium titanate \\left(\\mathrm{BaTiO}_{3}\\right) structure. What is the coordination number of the \\mathrm{Ti}^{4+} ion in terms of surrounding \\mathrm{O}^{2-} ions?\n[a] 1\n[b] 2\n[c] 3\n[d] 4\n[e] 5\n[f] 6\n[g] 7\n[h] 8", "answer": "According to Fig. 3.10, the central \\mathrm{Ti}^{4+} ion is surrounded by six \\mathrm{O}^{2-} ions, one residing at each of the six cube faces.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的多个选项中选择正确答案，且答案明确指出了正确的选项。 | 知识层次: 题目考查对理想钛酸钡结构中Ti4+离子配位数的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆理想BaTiO3结构中Ti4+离子的配位数。题目提供了明确的提示（参考图3.10），且正确选项（6）是晶体学中的常见配位数，属于简单概念识别范畴，无需复杂分析或推理。", "convertible": true, "correct_option": "f", "choice_question": "Consider the ideal barium titanate \\left(\\mathrm{BaTiO}_{3}\\right) structure. What is the coordination number of the \\mathrm{Ti}^{4+} ion in terms of surrounding \\mathrm{O}^{2-} ions?", "conversion_reason": "The question is already in a multiple-choice format with a clear correct answer provided.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4 (tetrahedral coordination)", "B": "6 (octahedral coordination)", "C": "8 (cubic coordination)", "D": "12 (face-centered cubic coordination)" }, "correct_answer": "B", "explanation": "In the ideal perovskite structure of BaTiO3, Ti4+ ions occupy the octahedral sites formed by six O2- ions, giving a coordination number of 6. Option A exploits the common tetrahedral coordination seen in many oxides, while Option C mimics the coordination of Ba2+ in the same structure. Option D uses the FCC coordination number which is irrelevant here but appears plausible for close-packed structures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4464, "question": "Borosilicate glasses and fused silica are resistant to thermal shock. Why is this so?", "answer": "Borosilicate glasses and fused silica are resistant to thermal shock because they have relatively low coefficients of thermal expansion; therefore, upon heating or cooling, the difference in the degree of expansion or contraction across a cross-section of a ware that is constructed from these materials will be relatively low.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么硼硅酸盐玻璃和熔融石英具有抗热震性，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释硼硅酸盐玻璃和熔融石英抗热震性的原因，涉及材料的热膨胀系数与热应力之间的关系，需要综合运用材料科学中的热力学和力学知识进行推理分析，属于对材料性能机理的深入解释。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "They have relatively low coefficients of thermal expansion.", "choice_question": "Why are borosilicate glasses and fused silica resistant to thermal shock?", "conversion_reason": "The answer is a standard explanation that can be rephrased into a correct option for a multiple-choice question. The question can be adapted to a 'why' format suitable for a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "They have relatively low coefficients of thermal expansion", "B": "Their high elastic modulus prevents crack propagation during rapid temperature changes", "C": "The presence of boron creates stress-relieving microstructures in the glass network", "D": "Their high thermal conductivity allows rapid heat dissipation" }, "correct_answer": "A", "explanation": "The correct answer is A because thermal shock resistance is primarily determined by low thermal expansion coefficients, which minimize internal stresses during temperature changes. Option B is a cognitive bias trap - while elastic modulus is important for mechanical strength, it's not the primary factor for thermal shock. Option C exploits professional intuition by suggesting a plausible-sounding but incorrect microstructure mechanism. Option D is a multi-level verification trap - while thermal conductivity is relevant, it's secondary to thermal expansion in determining thermal shock resistance.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1312, "question": "Homogeneous nucleation of crystal nuclei relies on (6) to provide nucleation work equivalent to the interfacial energy (7).", "answer": "energy fluctuation; 1/3", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要填写两个空白处的内容，分别是\"energy fluctuation\"和\"1/3\"，这属于简答题的填空形式，需要根据知识理解来填写正确答案，而不是从选项中选择或进行判断。 | 知识层次: 题目考查对均相成核过程中能量波动和界面能比例的基本概念记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需考生回忆并填写两个关键术语（能量波动和1/3），无需进行概念解释或复杂推导。题目直接考查均质形核的核心定义参数，属于对单一知识点的机械性记忆，符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "energy fluctuation", "choice_question": "Homogeneous nucleation of crystal nuclei relies on which of the following to provide nucleation work equivalent to the interfacial energy?", "conversion_reason": "The answer is a standard term (energy fluctuation) which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "energy fluctuation", "B": "lattice vibration amplitude", "C": "surface tension gradient", "D": "critical undercooling temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because homogeneous nucleation fundamentally relies on random energy fluctuations to overcome the interfacial energy barrier. Option B is a cognitive bias trap - while lattice vibrations contribute to energy fluctuations, they are not the direct source of nucleation work. Option C exploits surface tension being related to interfacial energy, but gradients are irrelevant in homogeneous nucleation. Option D is a multi-level trap - while undercooling provides the driving force, the actual nucleation work comes from energy fluctuations, not the temperature itself.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 45, "question": "Barium titanate is an important ferroelectric ceramic with a perovskite crystal structure. What are the coordination numbers of the ions in this structure?", "answer": "The coordination numbers of Ba²⁺, Ti⁴⁺, and O²⁻ are 12, 6, and 6, respectively.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释离子在晶体结构中的配位数，答案需要文字描述而非选择、判断或计算。 | 知识层次: 题目考查对钙钛矿晶体结构中离子配位数的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即Barium titanate晶体结构中各离子的配位数。不需要进行复杂的分析或推理，只需直接回忆相关知识即可选择正确答案。因此，属于基本定义简答的难度等级。", "convertible": true, "correct_option": "The coordination numbers of Ba²⁺, Ti⁴⁺, and O²⁻ are 12, 6, and 6, respectively.", "choice_question": "What are the coordination numbers of the ions in the perovskite crystal structure of barium titanate?", "conversion_reason": "The answer is a standard and specific description of coordination numbers, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ba²⁺:12, Ti⁴⁺:6, O²⁻:6", "B": "Ba²⁺:8, Ti⁴⁺:6, O²⁻:12", "C": "Ba²⁺:6, Ti⁴⁺:6, O²⁻:6", "D": "Ba²⁺:12, Ti⁴⁺:4, O²⁻:8" }, "correct_answer": "A", "explanation": "The correct coordination numbers reflect the perovskite structure where Ba²⁺ occupies the cuboctahedral site (12-fold coordination), Ti⁴⁺ is octahedrally coordinated (6-fold), and each O²⁻ is coordinated to 2 Ti⁴⁺ and 4 Ba²⁺ (6-fold). Option B reverses the coordination of Ba²⁺ and O²⁻, exploiting the common mistake of confusing their roles. Option C uses equal coordination numbers, appealing to symmetry misconceptions. Option D incorrectly reduces Ti⁴⁺ coordination to 4, mimicking zirconate structures which are common distractors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4321, "question": "Two intermetallic compounds, A B and A B_{2}, exist for elements A and B. If the compositions for A B and A B_{2} are 34.3 wt% \\mathrm{~A}-65.7 wt% \\mathrm{~B} and 20.7 wt% \\mathrm{~A}-79.3 wt% \\mathrm{~B}, respectively, and element A is potassium, identify element B.", "answer": "element b is arsenic (as), with an atomic weight of 74.92 \\, \\text{g/mol} . the two intermetallic compounds are \\text{kas} and \\text{kas}_2 .", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过分析和计算识别元素B，并给出具体的答案（砷），这需要文字解释和论述，而不是简单的选择或判断。答案的形式也是文字描述，而非数值或选项。 | 知识层次: 题目需要将重量百分比转换为原子百分比，并利用原子量信息推断未知元素的原子量，涉及多步计算和概念关联。虽然不涉及复杂的推理分析或机理解释，但需要一定的综合分析能力来解决问题。 | 难度: 在选择题中属于较高难度，需要综合运用多个知识点并进行多步计算。题目要求识别元素B，涉及原子量计算和化学计量关系分析。解题步骤包括：1) 理解题目中给出的两种化合物的组成百分比；2) 利用元素A（钾）的已知原子量计算元素B的原子量；3) 通过计算结果匹配元素B的可能选项。此外，还需要对化学计量关系和元素周期表有一定的了解。这种综合分析能力和多步计算的要求使得该题目在选择题型中属于较高难度。", "convertible": true, "correct_option": "arsenic (As)", "choice_question": "Two intermetallic compounds, A B and A B_{2}, exist for elements A and B. If the compositions for A B and A B_{2} are 34.3 wt% A-65.7 wt% B and 20.7 wt% A-79.3 wt% B, respectively, and element A is potassium, which of the following is element B?", "conversion_reason": "The answer is a standard chemical element name, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "arsenic (As)", "B": "selenium (Se)", "C": "bromine (Br)", "D": "krypton (Kr)" }, "correct_answer": "A", "explanation": "The correct answer is arsenic (As) because the atomic weight ratio calculation based on the given weight percentages and potassium's atomic weight (39.10 g/mol) leads to an atomic weight of ~74.92 g/mol for element B, which matches arsenic. Selenium (Se) is a strong distractor as its atomic weight (78.97 g/mol) is close but slightly higher. Bromine (Br) exploits the cognitive bias of halogens forming compounds with alkali metals, though the weight percentages don't match. Krypton (Kr) is a noble gas trap, playing on the misconception that noble gases can't form compounds, though they actually can under extreme conditions (which are irrelevant here).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1810, "question": "Among various layered silicate structures, the unit cell parameters that are similar are a.a0 and b0 b.a0 and c0 c.c0 and b0 d.c0", "answer": "a", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项a、b、c、d中选择正确答案 | 知识层次: 题目考查对层状硅酸盐结构单元晶胞参数的基本概念记忆，只需识别相似参数即可，不涉及复杂分析或应用。 | 难度: 该题目属于基础概念记忆类型，仅需识别和回忆层状硅酸盐结构中单元晶胞参数的相似性。题目直接给出了正确选项，无需复杂辨析或深度理解，属于选择题型中最简单的难度等级。", "convertible": true, "correct_option": "a", "choice_question": "Among various layered silicate structures, the unit cell parameters that are similar are", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The basal plane spacing (d001) in both kaolinite and montmorillonite", "B": "The a-axis length in pyrophyllite and the c-axis length in talc", "C": "The interlayer distance in muscovite and the unit cell height in phlogopite", "D": "The b-dimension in all 1:1 layer silicates and 2:1 layer silicates" }, "correct_answer": "D", "explanation": "The correct answer is D because the b-dimension is consistently around 9Å across all layer silicate structures due to the similar Si-O tetrahedral sheet geometry. Option A is a cognitive bias trap - while both are clay minerals, their d001 spacings differ significantly (7Å vs 12-15Å). Option B exploits professional intuition by pairing different axes from structurally similar but distinct minerals. Option C creates a multi-level verification trap by comparing two different types of measurements in similar but non-identical minerals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4212, "question": "For alloy A with atomic weight 77.4 g/mol, density 8.22 g/cm³, and atomic radius 0.125 mm, determine whether its crystal structure is FCC, BCC, or simple cubic and then justify your determination.", "answer": "for alloy a, its crystal structure is simple cubic.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的原子量、密度和原子半径等参数进行计算，以确定晶体结构类型，并需要应用相关公式进行推导和验证。答案虽然简短，但需要通过计算过程得出。 | 知识层次: 题目需要应用密度公式和晶体结构几何关系进行多步计算，涉及原子半径、原子量和密度的综合运用，需要理解不同晶体结构的堆积方式并进行比较分析，属于中等难度的应用题型。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念并进行比较分析。题目要求考生掌握晶体结构的基本概念，能够进行密度、原子半径和原子量的计算，并综合分析这些数据来确定晶体结构类型。虽然题目给出了正确选项，但解题过程涉及多步骤计算和概念关联，需要考生具备一定的综合分析能力。", "convertible": true, "correct_option": "simple cubic", "choice_question": "For alloy A with atomic weight 77.4 g/mol, density 8.22 g/cm³, and atomic radius 0.125 mm, its crystal structure is:", "conversion_reason": "The original question is a calculation problem with a definitive answer (simple cubic), which can be converted into a multiple-choice question by providing the possible crystal structures (FCC, BCC, simple cubic) as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Simple cubic", "B": "Face-centered cubic (FCC)", "C": "Body-centered cubic (BCC)", "D": "Hexagonal close-packed (HCP)" }, "correct_answer": "A", "explanation": "To determine the crystal structure, we calculate the number of atoms per unit cell using the given data. The atomic radius is 0.125 nm (not mm), and the volume of the unit cell can be calculated from the density and atomic weight. For simple cubic, the edge length (a) is 2r, giving a packing fraction that matches the calculated density. FCC and BCC would require higher densities due to their higher packing fractions, while HCP is not applicable here as it's not one of the given options in the original question. The interference strategies used are: (B) FCC is a common high-density structure that might seem plausible, (C) BCC is often seen in alloys and could be an intuitive guess, and (D) HCP is included to exploit the tendency to consider all common crystal structures even when not relevant.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2230, "question": "The tungsten filament in a light bulb operates at very high temperatures, leading to significant grain growth. When large grains spanning the filament form, the filament becomes brittle under certain conditions and may fracture due to stresses caused by thermal expansion during heating and cooling. Find a method to extend the lifespan of the tungsten filament.", "answer": "Dispersed, particulate second phases (such as $\\\\mathrm{ThO}_{2}$) can be introduced into the tungsten filament to restrict grain growth. If the volume fraction of $\\\\mathrm{ThO}_{2}$ is $\\\\varphi$ and the radius is $r$, the limiting grain size $R = \\\\frac{4r}{3\\\\varphi(1+\\\\cos\\\\alpha)}$ (where $\\\\alpha$ is the contact angle). By selecting appropriate values of $\\\\varphi$ and $r$ to minimize $R$, grain growth can be effectively halted. Since grain refinement significantly reduces the brittleness of the filament, it becomes less prone to fracture, thereby effectively extending its lifespan.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求提出一个方法来延长钨丝寿命，并给出了详细的解释和公式应用，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求综合运用材料科学知识（如晶粒生长限制机制、第二相颗粒的作用）进行推理分析，解释如何通过控制第二相颗粒的参数（体积分数和半径）来优化钨丝性能，涉及多概念关联和机理解释。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Dispersed, particulate second phases (such as $\\mathrm{ThO}_{2}$) can be introduced into the tungsten filament to restrict grain growth.", "choice_question": "Which method can effectively extend the lifespan of the tungsten filament in a light bulb by restricting grain growth?", "conversion_reason": "The answer is a standard method described in technical terms, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Introducing dispersed ThO2 particles to pin grain boundaries", "B": "Increasing the operating temperature to promote dynamic recrystallization", "C": "Applying a protective oxide coating to reduce surface diffusion", "D": "Using zone refining to achieve ultra-high purity tungsten" }, "correct_answer": "A", "explanation": "The correct answer A utilizes second-phase particles to mechanically restrict grain boundary migration, a well-established method in tungsten filaments. Option B exploits the common misconception that recrystallization always improves properties, while in reality it would accelerate grain growth. Option C plays on the intuitive appeal of surface protection but ignores that bulk diffusion dominates at these temperatures. Option D uses the 'more pure is better' fallacy, when in fact some impurities are needed for grain boundary pinning.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2932, "question": "In ionic crystals, if Schottky defects are formed in a local region, the concentration of cation vacancies in this region is equal to . \\n\\n(A) Anion vacancy concentration (B) Interstitial anion concentration (C) Interstitial cation concentration", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项（A、B、C）中选择正确答案，符合选择题的特征 | 知识层次: 题目考查离子晶体中肖特基缺陷的基本概念，即阳离子空位浓度与阴离子空位浓度的关系，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆Schottky缺陷的定义即可得出正确答案。题目选项设计简单，没有涉及复杂的概念辨析或深度理解，符合等级1的简单概念识别标准。", "convertible": true, "correct_option": "Anion vacancy concentration", "choice_question": "In ionic crystals, if Schottky defects are formed in a local region, the concentration of cation vacancies in this region is equal to .", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The product of anion vacancy concentration and Frenkel defect concentration", "B": "The square root of anion vacancy concentration", "C": "Anion vacancy concentration", "D": "The sum of anion and cation interstitial concentrations" }, "correct_answer": "C", "explanation": "In Schottky defects, cation vacancies are created in equal numbers to anion vacancies to maintain charge neutrality, making option C correct. Option A introduces a complex but incorrect relationship by multiplying with Frenkel defects. Option B uses a mathematically plausible but physically incorrect square root relationship. Option D misleadingly combines interstitial concentrations which are irrelevant to Schottky defects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 373, "question": "What are the characteristics or features of recrystallization nucleation sites?", "answer": "Locally high dislocation density/deformation stored energy, or significant differences in dislocation density; near high-mobility high-angle grain boundaries.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释再结晶成核位点的特征，答案提供了详细的文字描述和论述，没有涉及选择、判断或计算。 | 知识层次: 题目考查对再结晶成核位点特征的基础概念记忆和理解，属于定义和基本原理的记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆，但需要考生理解并区分再结晶形核位点的具体特征（如局部高位错密度/变形储存能、位错密度显著差异、靠近高迁移率大角度晶界等），而不仅仅是简单的定义复述。这要求考生对相关概念有一定的理解和记忆深度，但不需要进行复杂的分析或推理。", "convertible": true, "correct_option": "Locally high dislocation density/deformation stored energy, or significant differences in dislocation density; near high-mobility high-angle grain boundaries.", "choice_question": "Which of the following are characteristics or features of recrystallization nucleation sites?", "conversion_reason": "The answer is a standard description of the characteristics of recrystallization nucleation sites, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Locally high dislocation density/deformation stored energy", "B": "Regions with perfect crystallinity and zero defects", "C": "Areas with uniform elastic strain distribution", "D": "Low-angle grain boundaries with misorientation <15°" }, "correct_answer": "A", "explanation": "Correct answer A is based on the fundamental principle that recrystallization nucleation requires sufficient stored energy from deformation. Option B exploits the common misconception that nucleation occurs in perfect crystals, while in reality defects are essential. Option C uses the intuitive but incorrect association with uniform strain, whereas nucleation requires strain gradients. Option D targets the subtle distinction between high-angle (effective) and low-angle (ineffective) grain boundaries for nucleation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3524, "question": "Explain the role of Cu element in aluminum alloys", "answer": "Copper in aluminum not only significantly enhances the room temperature strength of aluminum alloys through solid solution strengthening and precipitation strengthening, but also improves the heat resistance of aluminum alloys. Therefore, copper is a primary alloying element in high-strength aluminum alloys and heat-resistant aluminum alloys.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释铜元素在铝合金中的作用，需要文字解释和论述，答案提供了详细的解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释铜元素在铝合金中的作用，涉及固溶强化和沉淀强化等概念的综合应用，需要理解铜元素如何通过这些机制提高铝合金的强度和耐热性。虽然不涉及复杂的计算或深度推理，但需要对多个概念进行关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解铜元素在铝合金中的多重作用（固溶强化、沉淀强化、耐热性提升），并能综合分析这些效应与合金性能的关联。题目涉及中等应用层次的知识点，要求考生将多个概念联系起来，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Copper in aluminum not only significantly enhances the room temperature strength of aluminum alloys through solid solution strengthening and precipitation strengthening, but also improves the heat resistance of aluminum alloys. Therefore, copper is a primary alloying element in high-strength aluminum alloys and heat-resistant aluminum alloys.", "choice_question": "What is the role of Cu element in aluminum alloys?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Primarily increases electrical conductivity while slightly reducing density", "B": "Forms intermetallic compounds that significantly increase hardness but reduce ductility", "C": "Enhances strength through solid solution and precipitation strengthening, while improving heat resistance", "D": "Acts as a grain refiner to improve toughness by preventing grain growth during heat treatment" }, "correct_answer": "C", "explanation": "The correct answer is C because copper in aluminum alloys primarily functions through solid solution strengthening and the formation of θ' (Al2Cu) precipitates during aging, which significantly enhance strength. It also improves heat resistance by stabilizing these precipitates at elevated temperatures. Option A is incorrect as Cu actually decreases electrical conductivity in Al alloys. Option B is partially correct but misleading as it overemphasizes hardness increase while underrepresenting Cu's primary strengthening mechanisms. Option D describes the role of Ti or Zr, not Cu, exploiting grain refinement concept confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 765, "question": "What are the characteristics of intrinsic diffusion?", "answer": "The activation energy of intrinsic diffusion consists of two parts: vacancy formation energy and particle migration energy, and intrinsic diffusion dominates at high temperatures.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释intrinsic diffusion的特性，答案提供了文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查对固有扩散（intrinsic diffusion）基本特征的理解和记忆，包括其激活能的组成部分以及在高温下的主导作用。这属于基础概念的记忆和理解范畴，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解并区分本征扩散的两个关键组成部分（空位形成能和粒子迁移能），以及掌握本征扩散在高温条件下的主导作用。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "The activation energy of intrinsic diffusion consists of two parts: vacancy formation energy and particle migration energy, and intrinsic diffusion dominates at high temperatures.", "choice_question": "Which of the following correctly describes the characteristics of intrinsic diffusion?", "conversion_reason": "The answer is a standard description of the characteristics of intrinsic diffusion, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy of intrinsic diffusion consists of two parts: vacancy formation energy and particle migration energy, and intrinsic diffusion dominates at high temperatures.", "B": "Intrinsic diffusion is primarily governed by grain boundary effects and becomes significant at temperatures below 0.5Tm.", "C": "The diffusion coefficient for intrinsic diffusion follows an inverse temperature dependence due to lattice vibration effects.", "D": "Intrinsic diffusion occurs only in ionic materials where charge neutrality must be maintained during defect migration." }, "correct_answer": "A", "explanation": "The correct answer is A because intrinsic diffusion indeed involves both vacancy formation and migration energies, and dominates at high temperatures where thermal vacancies are abundant. Option B is incorrect because it confuses intrinsic diffusion with grain boundary diffusion. Option C is wrong as it reverses the actual Arrhenius temperature dependence. Option D is a trap that incorrectly limits intrinsic diffusion to ionic materials only, while it actually occurs in all crystalline materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 792, "question": "Explain what type of solid solution compound austenite in carbon steel belongs to", "answer": "Austenite is an interstitial solid solution of carbon in γ-Fe", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释奥氏体在碳钢中属于哪种固溶体类型，需要文字解释和论述，答案也以文字形式给出具体解释 | 知识层次: 题目考查对奥氏体（austenite）这一基本概念的记忆和理解，要求回答其属于何种固溶体类型，属于材料科学基础知识的范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆（定义和分类），但需要考生准确理解并区分不同类型的固溶体（间隙固溶体 vs. 置换固溶体），并正确识别奥氏体的具体组成。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "Austenite is an interstitial solid solution of carbon in γ-Fe", "choice_question": "What type of solid solution compound does austenite in carbon steel belong to?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial solid solution of carbon in γ-Fe", "B": "Substitutional solid solution of carbon in α-Fe", "C": "Intermetallic compound of Fe3C", "D": "Interstitial compound with carbon occupying substitutional sites" }, "correct_answer": "A", "explanation": "Austenite is correctly defined as an interstitial solid solution where carbon atoms occupy the octahedral interstitial sites in the face-centered cubic (γ-Fe) lattice. Option B is wrong because it describes substitutional solution in α-Fe (ferrite), exploiting the common confusion between austenite and ferrite structures. Option C is a trap using the cementite (Fe3C) compound that forms at higher carbon concentrations. Option D combines contradictory concepts of interstitial and substitutional sites, targeting AI's tendency to merge related but distinct concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3034, "question": "The Tf of the glass phase in ceramics is (6).", "answer": "(6) viscous flow temperature", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个术语（viscous flow temperature）作为答案，属于需要简短文字回答的类型，而不是从多个选项中选择或进行判断/计算。 | 知识层次: 题目考查的是玻璃相在陶瓷中的Tf（viscous flow temperature）这一基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察对\"Tf\"这一基础定义的记忆，属于最基础的概念记忆层次。题目直接给出术语定义选项，无需任何解释、分析或推理步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "viscous flow temperature", "choice_question": "The Tf of the glass phase in ceramics is:", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "viscous flow temperature", "B": "glass transition temperature", "C": "melting point of crystalline phase", "D": "sintering onset temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because Tf specifically denotes the temperature at which the glass phase becomes fluid enough for viscous flow. B is a strong distractor as Tg (glass transition temperature) is commonly confused with Tf, but represents the onset of glass softening. C exploits confusion between glass and crystalline phases, while D targets those who associate ceramic processing temperatures with sintering rather than glass behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 541, "question": "Deformation texture", "answer": "Deformation texture: As the amount of plastic deformation increases, the phenomenon where a certain crystallographic orientation of the deformed polycrystal tends to become consistent.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Deformation texture\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对\"Deformation texture\"这一基本概念的定义和现象描述，属于基础概念的记忆和理解范畴，不涉及应用或分析层面的要求。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆\"Deformation texture\"的定义和基本原理，但不需要进行复杂的概念体系阐述或多概念比较分析。虽然需要掌握一定的专业术语和基本概念，但整体上仍属于中等偏下的难度水平。", "convertible": true, "correct_option": "As the amount of plastic deformation increases, the phenomenon where a certain crystallographic orientation of the deformed polycrystal tends to become consistent.", "choice_question": "What is deformation texture?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The preferential alignment of crystal orientations due to plastic deformation", "B": "The surface roughness pattern caused by mechanical working", "C": "The change in optical properties during strain hardening", "D": "The residual stress distribution after cold working" }, "correct_answer": "A", "explanation": "Option A is correct as deformation texture specifically refers to the development of preferred crystallographic orientations during plastic deformation. Option B exploits the common confusion between macroscopic surface features and microscopic crystallographic alignment. Option C targets the misconception that texture relates to optical property changes rather than crystallographic orientation. Option D leverages the intuitive but incorrect association between texture and residual stress patterns.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 612, "question": "What are the two basic phases that make up the room-temperature equilibrium structure of iron-carbon alloys", "answer": "Ferrite (α)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释铁碳合金在室温下的平衡结构的基本相，需要文字解释和论述，答案形式为简短的文字描述而非选择或判断。 | 知识层次: 题目考查铁碳合金室温平衡结构的基本相组成，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求识别铁碳合金室温平衡结构的基本相之一（铁素体α），属于最基础的定义性知识。不需要解释或比较多个概念，只需记忆单一知识点即可作答，因此属于等级1的基本定义简答难度。", "convertible": true, "correct_option": "Ferrite (α)", "choice_question": "Which of the following is one of the two basic phases that make up the room-temperature equilibrium structure of iron-carbon alloys?", "conversion_reason": "The answer is a standard term (Ferrite (α)), which can be used as a correct option in a multiple-choice question. The original question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ferrite (α)", "B": "Martensite", "C": "Pearlite", "D": "Austenite (γ)" }, "correct_answer": "A", "explanation": "Ferrite (α) is one of the two basic phases in room-temperature equilibrium structure of iron-carbon alloys (along with cementite). Martensite is a non-equilibrium phase formed by rapid quenching. Pearlite is a lamellar mixture of ferrite and cementite, not a basic phase. Austenite (γ) is stable only at elevated temperatures, creating a common misconception for those recalling high-temperature phase diagrams.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4338, "question": "The mass fractions of total ferrite and total cementite in an iron-carbon alloy are 0.88 and 0.12 , respectively. Is this a hypoeutectoid or hypereutectoid alloy? Why?", "answer": "the alloy is hypereutectoid since c_0 is greater than 0.76 \\, \\text{wt% c}.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么该合金是过共析合金，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要学生理解铁碳合金相图的基本概念，并能根据给定的质量分数计算碳含量，进而判断合金类型。这涉及到多步推理和概念关联，但不需要复杂的综合分析或创新应用。 | 难度: 在选择题中属于中等难度，需要理解铁碳合金相图的基本概念，能够区分亚共析和过共析合金的特征，并进行简单的质量分数计算和比较。虽然题目涉及多步计算和概念关联，但在选择题型中，正确选项已经提供了关键判断依据，降低了部分分析难度。", "convertible": true, "correct_option": "the alloy is hypereutectoid since c_0 is greater than 0.76 wt% c", "choice_question": "The mass fractions of total ferrite and total cementite in an iron-carbon alloy are 0.88 and 0.12, respectively. Is this a hypoeutectoid or hypereutectoid alloy?", "conversion_reason": "The answer is a standard terminology and concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hypereutectoid, because the carbon content is above 0.76 wt%", "B": "Hypoeutectoid, because ferrite is the dominant phase", "C": "Hypereutectoid, because cementite forms before pearlite", "D": "Hypoeutectoid, because the alloy contains less than 6.7 wt% carbon" }, "correct_answer": "A", "explanation": "The correct answer is A because the mass fractions indicate a carbon content above the eutectoid composition (0.76 wt%). B is a cognitive bias trap - while ferrite is dominant, it's the carbon content that determines classification. C is a professional intuition trap - while true for hypereutectoid alloys, it's not the defining characteristic. D is a multi-level verification trap - while technically true, it doesn't address the critical eutectoid composition threshold.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3484, "question": "Is tempering high-speed steel at 560°C considered quenching and tempering treatment? Why?", "answer": "No. Quenching and tempering treatment refers to high-temperature tempering (typically 500~650°C) after quenching to obtain tempered sorbite structure, which provides good comprehensive mechanical properties. However, tempering high-speed steel at 560°C aims to achieve dispersion hardening and secondary quenching phenomena, improving hardness and wear resistance, with the microstructure being tempered martensite + a small amount of retained austenite + carbides.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么在560°C回火高速钢不被认为是淬火和回火处理，答案需要详细的文字解释和论述，涉及材料科学中的热处理原理和微观结构变化。 | 知识层次: 题目要求分析高速钢在560°C回火与淬火回火处理的区别，涉及对热处理工艺目的、微观组织演变和性能影响的深入理解。需要综合运用材料科学知识，解释不同热处理工艺的机理和效果，属于复杂分析和推理的范畴。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "No. Quenching and tempering treatment refers to high-temperature tempering (typically 500~650°C) after quenching to obtain tempered sorbite structure, which provides good comprehensive mechanical properties. However, tempering high-speed steel at 560°C aims to achieve dispersion hardening and secondary quenching phenomena, improving hardness and wear resistance, with the microstructure being tempered martensite + a small amount of retained austenite + carbides.", "choice_question": "Is tempering high-speed steel at 560°C considered quenching and tempering treatment? Why?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct explanation as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because 560°C falls within the typical tempering temperature range for most steels", "B": "No, because high-speed steel requires special cryogenic treatment before tempering", "C": "Yes, because it produces the same tempered sorbite structure as conventional quenching and tempering", "D": "No, because the purpose and resulting microstructure are fundamentally different from conventional quenching and tempering" }, "correct_answer": "D", "explanation": "The correct answer is D because tempering high-speed steel at 560°C aims for dispersion hardening and secondary hardening effects, producing tempered martensite with carbides, not the tempered sorbite structure characteristic of conventional quenching and tempering. Option A exploits the temperature range similarity without considering the material-specific purpose. Option B introduces an irrelevant cryogenic treatment requirement. Option C incorrectly assumes microstructure equivalence despite different objectives.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4301, "question": "Briefly explain the difference between fatigue striations and beachmarks in terms of size.", "answer": "With regard to size, beachmarks are normally of macroscopic dimensions and may be observed with the naked eye; fatigue striations are of microscopic size and it is necessary to observe them using electron microscopy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要解释疲劳条纹和海滩标记在尺寸上的区别，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查疲劳条纹和海滩标记的基本定义和尺寸差异，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但要求考生能够区分疲劳条纹和海滩标记在尺寸上的差异，并理解观察它们所需的不同技术手段（肉眼观察与电子显微镜）。这需要考生不仅记住定义，还要能够进行简单的概念对比和解释，属于概念解释和描述的层次。", "convertible": true, "correct_option": "With regard to size, beachmarks are normally of macroscopic dimensions and may be observed with the naked eye; fatigue striations are of microscopic size and it is necessary to observe them using electron microscopy.", "choice_question": "What is the difference between fatigue striations and beachmarks in terms of size?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Beachmarks are macroscopic features visible to the naked eye, while fatigue striations require electron microscopy due to their microscopic size", "B": "Both features are microscopic but beachmarks appear larger due to their curved morphology", "C": "Fatigue striations are actually larger than beachmarks because they represent individual crack propagation events", "D": "Their sizes are identical but beachmarks appear distinct due to environmental interactions" }, "correct_answer": "A", "explanation": "Correct answer A reflects the fundamental size difference where beachmarks are macroscopic (visible to naked eye) while striations are microscopic (require electron microscopy). Option B exploits the common misconception that curved features appear larger. Option C reverses the size relationship to trap those who confuse crack propagation mechanisms. Option D uses the false equivalence strategy by suggesting identical sizes with different appearances.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3858, "question": "A steel contains 18 % cementite and 82 % ferrite at room temperature. Estimate the carbon content of the steel.", "answer": "the carbon content of the steel is 1.20 % c.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算来估计钢中的碳含量，需要应用相关的材料科学公式和数值计算。答案是一个具体的数值结果（1.20 % c），这表明解答过程涉及计算而非选择或判断。 | 知识层次: 题目需要应用铁碳相图的知识，通过已知的相组成比例（18% cementite和82% ferrite）来计算碳含量。这涉及到多步计算和概念关联，需要理解相图的基本原理和相组成的计算方法，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图中渗碳体和铁素体的组成比例关系，并进行多步计算来推导碳含量。虽然题目提供了具体比例，但需要考生掌握相图知识并正确应用杠杆定律进行计算，属于综合性计算问题。", "convertible": true, "correct_option": "1.20 % c", "choice_question": "A steel contains 18 % cementite and 82 % ferrite at room temperature. What is the estimated carbon content of the steel?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.20 % C", "B": "0.18 % C", "C": "0.82 % C", "D": "2.14 % C" }, "correct_answer": "A", "explanation": "正确答案A基于杠杆定律计算：Cementite含6.67%C，Ferrite含0%C，总碳含量=0.18×6.67=1.20%。干扰项B利用认知偏差，直接将18% cementite误认为碳含量。干扰项C利用对称性错觉，错误地认为82% ferrite对应0.82%C。干扰项D利用专业直觉陷阱，采用Fe-Fe3C相图中最大碳溶解度，忽略题目给出的相比例条件。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 601, "question": "The coordination number of FCC structure is", "answer": "12", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答FCC结构的配位数，答案是一个具体的数值（12），不需要从多个选项中选择，也不需要判断对错或进行复杂的计算。虽然答案简短，但属于直接回答问题的简答题类型。 | 知识层次: 题目考查面心立方(FCC)结构配位数的记忆，属于晶体结构中最基础的概念性知识，不需要复杂的计算或分析过程。 | 难度: 在选择题型中，该题目仅考察对FCC结构配位数的基础定义记忆，属于最基础的概念性知识。题目仅需选择正确数字选项，无需任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "12", "choice_question": "The coordination number of FCC structure is:", "conversion_reason": "The answer is a specific numerical value, which can be easily converted into a multiple-choice question format with the correct option being the original answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "选项B", "C": "选项D", "D": "12" }, "correct_answer": "D", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 2336, "question": "Assuming the lattice constant of the alloy solid solution changes linearly with the increase of Zn atoms, and given the atomic radii of Cu and Zn are r_Cu=0.128nm and r_Zn=0.133nm respectively, find the average atomic radius r of the alloy with x_Zn=3%.", "answer": "The average atomic radius r is r = r_Cu + (r_Zn - r_Cu) × 3% = 0.128 + (0.133 - 0.128) × 0.03 nm = 0.1282 nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算，应用给定的公式和参数（原子半径和百分比）来求解合金的平均原子半径。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目涉及基本公式的直接应用和简单计算，仅需将给定的原子半径和百分比代入线性关系公式即可得出结果，无需多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需要直接套用给定的线性变化公式进行计算，属于单一公式直接计算的类型。解题步骤简单，无需复杂的推理或多步骤计算，符合等级1的难度标准。", "convertible": true, "correct_option": "0.1282 nm", "choice_question": "Assuming the lattice constant of the alloy solid solution changes linearly with the increase of Zn atoms, and given the atomic radii of Cu and Zn are r_Cu=0.128nm and r_Zn=0.133nm respectively, what is the average atomic radius r of the alloy with x_Zn=3%?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1282 nm", "B": "0.1285 nm", "C": "0.1330 nm", "D": "0.1305 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.1282 nm) because it accurately reflects the weighted average of atomic radii considering the 3% Zn composition. Option B (0.1285 nm) is a cognitive bias trap that overestimates the Zn contribution. Option C (0.1330 nm) is an intuition trap that incorrectly assumes the alloy takes the Zn radius. Option D (0.1305 nm) is a multi-level verification trap that averages the radii without considering the composition weighting.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2285, "question": "Calculate the critical volume fraction φtr of Al2O3 short fiber reinforced composite, given the matrix tensile strength σm=186MPa, yield strength σy=76MPa, and fiber stress σf=2190MPa.", "answer": "For Al2O3 short fibers, the critical volume fraction φtr = (σm - σy) / (σf - σy) = (186 - 76) / (2190 - 76) = 0.052.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过具体计算得出的数值结果 | 知识层次: 题目涉及基本公式的直接应用和简单计算，无需多步推理或综合分析，仅需理解公式中各参数的含义并进行数值代入即可求解。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目提供了所有必要的参数，并且只需要套用一个简单的公式（φtr = (σm - σy) / (σf - σy)）即可得出答案。计算过程简单，无需复杂的推理或多步骤的推导，因此属于最低难度等级。", "convertible": true, "correct_option": "0.052", "choice_question": "Calculate the critical volume fraction φtr of Al2O3 short fiber reinforced composite, given the matrix tensile strength σm=186MPa, yield strength σy=76MPa, and fiber stress σf=2190MPa.", "conversion_reason": "The calculation yields a specific numerical answer (0.052), which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.052", "B": "0.034", "C": "0.072", "D": "0.096" }, "correct_answer": "A", "explanation": "正确答案A是通过公式φtr=(σm-σy)/σf计算得出，其中σm=186MPa, σy=76MPa, σf=2190MPa。干扰项B错误地使用了σy作为分子，反映了屈服强度与拉伸强度的混淆。干扰项C基于错误的假设，即纤维应力需要乘以安全系数1.5。干扰项D则错误地将纤维应力与基体强度相加作为分母，违反了复合材料力学的基本原理。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 610, "question": "During the equilibrium solidification of alloys, the maximum carbon content in austenite is", "answer": "2.11%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的数值（2.11%），而不是从多个选项中选择或判断对错，也不需要复杂的计算过程，属于简短的直接回答类型 | 知识层次: 题目考查的是合金平衡凝固过程中奥氏体中碳含量的最大值这一基本概念的记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即奥氏体中碳含量的最大值。不需要解释或分析，只需直接回忆教材或课堂中给出的具体数值（2.11%）。属于最基础的定义性知识考查，解题步骤和认知要求极低。", "convertible": true, "correct_option": "2.11%", "choice_question": "During the equilibrium solidification of alloys, what is the maximum carbon content in austenite?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.11%", "B": "4.3%", "C": "0.77%", "D": "6.67%" }, "correct_answer": "A", "explanation": "The correct answer is A (2.11%) because this is the maximum solubility of carbon in austenite at the eutectic temperature (1147°C) according to the iron-carbon phase diagram. Option B (4.3%) is the eutectic composition, which is a common confusion point. Option C (0.77%) is the eutectoid composition, another frequent source of error. Option D (6.67%) is the carbon content in cementite (Fe3C), designed to exploit confusion between solubility limits and compound stoichiometry.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3838, "question": "An Al-Si alloy contains 15% primary \\beta and 85% eutectic microconstituent. Determine the composition of the alloy.", "answer": "25.71% si", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来确定合金的成分，答案是一个具体的数值（25.71% si），而不是选择、判断或文字解释。 | 知识层次: 题目需要应用杠杆定律进行多步计算，涉及相图分析和成分推导，需要将概念关联并进行综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解相图概念、进行多步计算（包括质量分数转换和相组成分析），并综合应用杠杆定律和共晶反应知识来推导合金成分。虽然题目提供了部分已知条件，但解题过程涉及多个关联步骤和概念整合，对学生的综合分析能力有一定要求。", "convertible": true, "correct_option": "25.71% Si", "choice_question": "An Al-Si alloy contains 15% primary β and 85% eutectic microconstituent. What is the composition of the alloy?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "25.71% Si", "B": "12.6% Si", "C": "18.3% Si", "D": "30.5% Si" }, "correct_answer": "A", "explanation": "正确答案A是通过杠杆定律计算得出：在Al-Si共晶体系中，共晶成分为12.6% Si，β相成分为99.83% Si。设合金成分为X% Si，则(99.83-X)/(X-12.6)=85/15，解得X=25.71% Si。干扰项B是共晶成分本身，利用认知偏差让人误以为可直接取用；干扰项C是15%和85%的加权平均值，设计为直觉计算陷阱；干扰项D接近β相成分，利用专业直觉让人高估硅含量。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3258, "question": "Given that brass with a zinc mass fraction of 30% takes 1 hour to complete recrystallization at a constant temperature of 400°C, and 2 hours at 390°C, calculate how much time is needed to complete recrystallization at a constant temperature of 420°C.", "answer": "Recrystallization of cold-deformed metal is also a thermally activated process, and the recrystallization rate follows the Arrhenius equation $$ V_{\\overline{{\\{\\}}}}=A^{\\prime}\\cdot\\mathrm{e}^{-Q/R T} $$ Since $V_{\\overrightarrow{\\vert\\overrightarrow{\\vert\\cdot}\\vert}}$ is inversely proportional to the time $\\scriptstyle t$ required to achieve a certain volume fraction $x_{\\upsilon}$, i.e., $V_{\\mathrm{\\#}}\\propto1/t$, we have $$ \\frac{1}{t_{1}}=A\\mathrm{e}^{-\\frac{Q}{R T_{1}}};\\frac{1}{t_{2}}=A\\mathrm{e}^{-\\frac{Q}{R T_{2}}};\\frac{1}{t_{3}}=A\\mathrm{e}^{-\\frac{Q}{R T_{3}}} $$ From the above three equations, dividing them pairwise yields $$ \\frac{t_{2}}{t_{1}}=\\mathrm{e}^{-\\frac{Q}{R}\\left(\\frac{1}{T_{1}}-\\frac{1}{T_{2}}\\right)};\\quad\\frac{t_{3}}{t_{1}}=\\mathrm{e}^{-\\frac{Q}{R}\\left(\\frac{1}{T_{1}}-\\frac{1}{T_{3}}\\right)} $$ Taking the natural logarithm and then dividing gives $$ \\frac{\\ln(t_{2}/t_{1})}{\\ln(t_{3}/t_{1})}=\\frac{1/T_{1}-1/T_{2}}{1/T_{1}-1/T_{3}} $$ Substituting $T_{1}=673~\\mathrm{K},t_{1}=1~\\mathrm{h};~T_{2}=663~\\mathrm{K},t_{2}=2~\\mathrm{h};~T_{3}=693~\\mathrm{K}$ into the above equation, we obtain $t_{3}=0.27$ h.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（Arrhenius方程）来解决具体问题，答案给出了详细的计算过程和最终的时间结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要应用Arrhenius方程进行推导和综合分析，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解Arrhenius方程及其在再结晶过程中的应用，进行多步计算和温度转换（摄氏到开尔文），并正确运用对数运算来求解时间。虽然题目提供了必要的公式和数据，但解题步骤较为复杂，涉及多个概念的综合运用和计算。", "convertible": true, "correct_option": "0.27 h", "choice_question": "Given that brass with a zinc mass fraction of 30% takes 1 hour to complete recrystallization at a constant temperature of 400°C, and 2 hours at 390°C, how much time is needed to complete recrystallization at a constant temperature of 420°C?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.27 h", "B": "0.5 h", "C": "1.5 h", "D": "2.7 h" }, "correct_answer": "A", "explanation": "正确答案A基于Arrhenius方程计算得出，通过390°C和400°C的数据点推导活化能后计算420°C的时间。干扰项B利用线性外推的直觉错误，C是温度降低的错误反向应用，D则放大了温度影响的常见高估错误。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2119, "question": "Point out the error in the following concept and correct it: 727°C is the allotropic transformation temperature of ferrite and austenite.", "answer": "The temperature indicated by the GS line is that of ferrite and austenite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出概念错误并进行纠正，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目考查对铁碳相图中关键温度点（GS线）的基础概念记忆和理解，属于材料科学中最基本的相变温度知识点，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（铁素体和奥氏体的同素异构转变温度），但需要考生不仅记住正确的温度值（727°C），还要能够识别并纠正题目中给出的错误概念（GS线对应的温度）。这要求考生对铁碳相图的基本概念有一定的理解和记忆，但不需要进行复杂的分析或推理。", "convertible": true, "correct_option": "The temperature indicated by the GS line is that of ferrite and austenite.", "choice_question": "Which of the following correctly identifies the error in the concept '727°C is the allotropic transformation temperature of ferrite and austenite' and provides the correct information?", "conversion_reason": "The original question asks to point out and correct an error in a specific concept, which can be rephrased into a multiple-choice format by providing the correct statement as one of the options. The answer is a standard correction that can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The temperature indicated by the GS line is that of ferrite and austenite", "B": "727°C is the eutectoid transformation temperature, not allotropic", "C": "The correct allotropic transformation occurs at 912°C for pure iron", "D": "This temperature represents the Curie point, not phase transformation" }, "correct_answer": "A", "explanation": "The correct answer A precisely identifies that the GS line in the iron-carbon phase diagram marks the boundary between ferrite and austenite. Option B is a strong distractor as it correctly states 727°C is the eutectoid temperature but falsely implies this makes the original statement about allotropic transformation completely wrong. Option C exploits the common confusion between pure iron's allotropic transformation (912°C) and steel's eutectoid transformation. Option D introduces an unrelated magnetic transition concept (Curie point) that shares similar temperature ranges, creating a red herring for models relying on temperature pattern matching.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3640, "question": "Calculate the planar packing fraction (ppf) on the (110) plane for ZnS (with the zinc blende structure).", "answer": "0.492", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算ZnS在(110)晶面上的平面堆积分数(ppf)，需要应用相关公式进行数值计算，最终答案为具体数值0.492，符合计算题的特征。 | 知识层次: 题目要求计算ZnS（闪锌矿结构）的(110)晶面的平面堆积分数(ppf)，这需要理解晶体结构、晶面指数和堆积分数的概念，并应用相关公式进行多步计算。虽然不涉及复杂的综合分析或创新应用，但需要将多个概念关联起来进行计算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、平面堆积分数的概念，并进行多步计算和综合分析。虽然题目给出了正确选项，但解题过程涉及对ZnS锌矿结构的理解、(110)平面的原子排列分析以及平面堆积分数的计算，这些步骤需要较强的概念关联和计算能力。", "convertible": true, "correct_option": "0.492", "choice_question": "What is the planar packing fraction (ppf) on the (110) plane for ZnS (with the zinc blende structure)?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.492", "B": "0.555", "C": "0.416", "D": "0.625" }, "correct_answer": "A", "explanation": "The correct answer is 0.492, calculated by considering the area occupied by atoms on the (110) plane in the zinc blende structure. Option B (0.555) is a common mistake from incorrectly assuming a simple cubic packing. Option C (0.416) results from miscalculating the atomic radii. Option D (0.625) is a trap for those confusing it with the packing fraction of a different crystal plane.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 5, "question": "What are the two types of voids in the closest packing of equal spheres?", "answer": "The closest packing of equal spheres includes hexagonal close packing and face-centered cubic close packing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和描述两种类型的空隙，答案提供了文字解释和论述，没有选项或计算要求。 | 知识层次: 题目考查对等径球体最密堆积中空隙类型的基本概念记忆，属于定义和分类层面的基础知识点，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆两种最密堆积类型的名称（六方最密堆积和面心立方最密堆积），属于基础概念记忆层面的直接提问，无需解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "hexagonal close packing and face-centered cubic close packing", "choice_question": "Which of the following are the two types of voids in the closest packing of equal spheres?", "conversion_reason": "The answer is a standard terminology that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hexagonal close packing and face-centered cubic close packing", "B": "Octahedral and tetrahedral voids", "C": "Interstitial and substitutional voids", "D": "Bravais and non-Bravais voids" }, "correct_answer": "A", "explanation": "The correct answer is A because these are the two distinct packing arrangements for closest packing of equal spheres. Option B is a strong distractor as octahedral and tetrahedral voids are types of interstitial sites within these packings, not the packing types themselves. Option C exploits confusion between void types and atomic substitution mechanisms. Option D misleads by referencing lattice classification terms unrelated to sphere packing geometries.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2751, "question": "In a copper crystal, when the a/2[101] dislocation on the (111) plane reacts with the a/2[011] dislocation on the (11-1) plane, describe the nature of the new dislocation.", "answer": "The new dislocation b=a/2[110] is a unit dislocation in the face-centered cubic structure; the direction of the dislocation line is along the intersection line [110] of the two crystal planes (111) and (111), so the dislocation is of edge type; the slip plane is (001), which is not a close-packed plane, hence it is a sessile dislocation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求描述新位错的性质，答案提供了详细的文字解释和论述，包括位错类型、方向和滑移面等特征，符合简答题的特点。 | 知识层次: 题目要求分析位错反应后新位错的性质，涉及位错线方向、滑移面判断以及位错类型（刃型位错）的确定。这需要综合运用晶体结构、位错理论和滑移系统知识，进行多步推理和机理解释，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅掌握位错反应的基本概念，还需要综合运用晶体学知识（如面心立方结构中的位错类型、滑移面判断）和矢量运算能力（如位错反应后的新柏氏矢量计算）。此外，题目涉及多个复杂分析步骤：1) 判断新位错的柏氏矢量性质 2) 确定位错线方向 3) 分析位错类型（刃型）4) 评估滑移面特性（非密排面）5) 最终得出固定位错的结论。这种需要多维度知识整合和机理深度解释的题目，在选择题中属于最复杂的类型。", "convertible": true, "correct_option": "The new dislocation b=a/2[110] is a unit dislocation in the face-centered cubic structure; the direction of the dislocation line is along the intersection line [110] of the two crystal planes (111) and (111), so the dislocation is of edge type; the slip plane is (001), which is not a close-packed plane, hence it is a sessile dislocation.", "choice_question": "In a copper crystal, when the a/2[101] dislocation on the (111) plane reacts with the a/2[011] dislocation on the (11-1) plane, which of the following describes the nature of the new dislocation?", "conversion_reason": "The answer is a standard description of the nature of the new dislocation, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The new dislocation b=a/2[110] is a unit edge dislocation with slip plane (001), making it sessile", "B": "The new dislocation b=a[110] is a perfect screw dislocation that can glide on both (111) and (11-1) planes", "C": "The reaction produces a mixed dislocation with Burgers vector a/6[112] that can cross-slip between the original planes", "D": "No stable dislocation forms as the reaction is energetically unfavorable in copper's FCC structure" }, "correct_answer": "A", "explanation": "The correct answer A describes the edge-type unit dislocation formed along the [110] intersection line with a non-close-packed (001) slip plane, making it sessile. Option B incorrectly suggests a perfect screw dislocation with double the Burgers vector magnitude. Option C falsely proposes a partial dislocation that would require stacking fault formation. Option D wrongly claims the reaction is energetically unfavorable, exploiting AI's tendency to overestimate energy considerations in dislocation reactions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 25, "question": "In CaO, the unit cell parameter a=0.480 nm, and the anions and cations are in contact with each other. Find the radius of O2-. The radius of Ca2+ is known to be 0.107 nm.", "answer": "In CaO, a=0.480 nm, and the anions and cations are in contact with each other. a=2(r+ + r-), therefore rO2-=(0.480 nm / 2) - 0.107 nm = 0.097 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的参数和公式进行数值计算，最终得出O2-的半径。解答过程涉及单位换算和简单的代数运算，符合计算题的特征。 | 知识层次: 题目涉及基本的公式应用和简单计算，只需要直接套用已知的半径和晶格参数关系公式进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。题目直接给出了单位晶胞参数和离子半径的关系公式（a=2(r+ + r-)），只需简单代入已知数值进行计算即可得出答案。虽然需要理解离子半径的概念和晶胞参数的关系，但解题步骤直接且无需复杂的推理或组合多个公式，因此在选择题型内属于等级2难度。", "convertible": true, "correct_option": "0.097 nm", "choice_question": "In CaO, the unit cell parameter a=0.480 nm, and the anions and cations are in contact with each other. The radius of Ca2+ is known to be 0.107 nm. What is the radius of O2-?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.097 nm", "B": "0.113 nm", "C": "0.133 nm", "D": "0.085 nm" }, "correct_answer": "A", "explanation": "In the NaCl-type structure of CaO, the sum of ionic radii equals half the unit cell parameter (a/2). Given a=0.480 nm and r(Ca2+)=0.107 nm, the correct calculation is r(O2-)=0.480/2 - 0.107=0.097 nm. Option B (0.113 nm) is a common mistake from misapplying the FCC packing factor. Option C (0.133 nm) comes from incorrectly assuming the same radius ratio as MgO. Option D (0.085 nm) results from reversing the cation/anion subtraction order, exploiting a common sign error tendency in calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2382, "question": "MgO dissolves into Al2O3 to form a solid solution, assuming the formation of cation interstitials. Write the reaction equation using Kroger-Vink notation.", "answer": "3MgO forms 3Mg••i + 2V•Al + 3OO× through Al2O3", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求使用Kroger-Vink符号写出反应方程式，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求使用Kroger-Vink符号表示固溶体形成反应，涉及缺陷化学的复杂概念和符号系统，需要深入理解缺陷反应机理和符号表示方法，并进行综合分析。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "3MgO forms 3Mg••i + 2V•Al + 3OO× through Al2O3", "choice_question": "MgO dissolves into Al2O3 to form a solid solution, assuming the formation of cation interstitials. Which of the following is the correct reaction equation using Kroger-Vink notation?", "conversion_reason": "The answer is a standard and specific reaction equation, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3MgO → 3Mg••i + 2V•Al + 3OO×", "B": "2MgO → 2Mg•Al + V••i + 2OO×", "C": "MgO + Al2O3 → Mg••Al + 2V•O + 3OO×", "D": "3MgO → 3Mg•Al + V••i + 3OO×" }, "correct_answer": "A", "explanation": "正确答案A正确反映了MgO溶解到Al2O3中形成阳离子间隙固溶体的过程，保持了电荷平衡和化学计量比。选项B错误地将间隙缺陷放在了Al位点而非Mg位点；选项C错误地引入了氧空位而非铝空位；选项D虽然保持了电荷平衡但错误地使用了替代缺陷而非间隙缺陷。这些干扰项利用了Kroger-Vink符号中电荷平衡和缺陷类型选择的常见混淆点。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3981, "question": "During the recovery of a cold-worked material, are grains with high strains replaced with new, unstrained grains?", "answer": "Grains with high strains are not replaced with new, unstrained grains.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（\"are grains with high strains replaced with new, unstrained grains?\"），而答案直接给出了对错判断（\"Grains with high strains are not replaced with new, unstrained grains.\"）。这符合判断题的特征。 | 知识层次: 题目考查对冷加工材料回复过程中晶粒变化的基本概念记忆和理解，属于基础概念层次。 | 难度: 该题目属于基础概念记忆层次，仅需判断关于冷加工材料恢复过程中晶粒变化的陈述是否正确。题目直接考察对基本定义和原理的记忆，无需深入理解或复杂分析，因此在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "Grains with high strains are not replaced with new, unstrained grains.", "choice_question": "During the recovery of a cold-worked material, are grains with high strains replaced with new, unstrained grains?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "During the recovery stage of annealing, all dislocations in cold-worked materials are completely eliminated.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "During recovery, dislocation density decreases through rearrangement and annihilation, but not all dislocations are eliminated. Complete dislocation elimination only occurs during recrystallization. This statement is false because it overgeneralizes the recovery process by suggesting total dislocation removal.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3066, "question": "Why are ceramic materials brittle?", "answer": "The brittleness of ceramic materials is influenced by both microstructural factors and macroscopic organization. From a microstructural perspective, the bonding in ceramic materials is ionic. If relative displacement occurs in ionic crystals, the electrical balance is lost, leading to the destruction of the ionic bonds, which is why materials bonded by ionic bonds are brittle. From a macroscopic organizational standpoint, ceramic materials contain a large number of pores (5%~10%), which reduce the load-bearing area when the ceramic is under stress, with pores being particularly prone to stress concentration. In summary, ceramic materials are brittle.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释陶瓷材料脆性的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求从微观结构和宏观组织两个角度综合分析陶瓷材料的脆性，涉及离子键的破坏机理和孔隙对力学性能的影响，需要深入理解和推理分析多个相关概念及其相互作用。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解陶瓷材料脆性的基本概念，还需要从微观结构（离子键特性）和宏观组织（孔隙影响）两个层面进行综合分析。正确选项涉及复杂的材料科学机理解释，需要考生具备将微观键合原理与宏观力学性能关联的能力，并能整合多个知识点进行推理分析。这种深度解释和全面分析的要求远超一般选择题的认知层次，属于需要高阶思维能力的复杂题目类型。", "convertible": true, "correct_option": "The brittleness of ceramic materials is influenced by both microstructural factors and macroscopic organization. From a microstructural perspective, the bonding in ceramic materials is ionic. If relative displacement occurs in ionic crystals, the electrical balance is lost, leading to the destruction of the ionic bonds, which is why materials bonded by ionic bonds are brittle. From a macroscopic organizational standpoint, ceramic materials contain a large number of pores (5%~10%), which reduce the load-bearing area when the ceramic is under stress, with pores being particularly prone to stress concentration. In summary, ceramic materials are brittle.", "choice_question": "Why are ceramic materials brittle?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ionic/covalent bonding nature prevents dislocation motion, while porosity creates stress concentration sites", "B": "High elastic modulus directly correlates with brittleness due to atomic bond stiffness", "C": "Lack of grain boundary sliding at room temperature compared to metals", "D": "Thermal expansion anisotropy causes microcracking during cooling from sintering temperatures" }, "correct_answer": "A", "explanation": "Correct answer A combines both the fundamental bonding limitation (dislocation immobility) and microstructural flaw effects. Distractors exploit common misconceptions: B falsely equates stiffness with brittleness (many stiff materials are tough), C incorrectly suggests grain boundary sliding as a primary deformation mechanism in ceramics, and D while true for some ceramics, doesn't explain inherent brittleness as it's a processing artifact rather than fundamental property.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1875, "question": "At low temperatures, the diffusion that generally occurs in solid materials is A. Intrinsic diffusion B. Extrinsic diffusion C. Random diffusion", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项A、B、C中选择正确答案 | 知识层次: 题目考查对固体材料中扩散类型的基本概念记忆和理解，特别是低温条件下扩散类型的分类知识。 | 难度: 在选择题型中，该题目属于基础概念记忆层次，要求考生区分不同扩散类型的定义。虽然需要理解\"低温下固体材料中通常发生的扩散类型\"这一知识点，但选项之间的区分度较为明显（本征扩散、非本征扩散、随机扩散），属于概念理解和简单辨析的难度层级。不需要复杂的分析过程，只需掌握基础定义即可正确作答。", "convertible": true, "correct_option": "B. Extrinsic diffusion", "choice_question": "At low temperatures, the diffusion that generally occurs in solid materials is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain boundary diffusion", "B": "Extrinsic diffusion", "C": "Vacancy-mediated diffusion", "D": "Interstitial diffusion" }, "correct_answer": "B", "explanation": "At low temperatures, extrinsic diffusion dominates because thermal energy is insufficient to create intrinsic defects (vacancies/interstitials). The key traps are: A) Grain boundary diffusion is plausible but requires polycrystalline materials, C) Vacancy-mediated seems intuitive but requires high temperatures for vacancy formation, D) Interstitial diffusion is faster but requires pre-existing interstitial defects which are rare at low T. The question exploits AI's tendency to associate 'low temperature' with 'fast paths' like grain boundaries, while the correct answer requires understanding defect thermodynamics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4205, "question": "What type(s) of bonding would be expected for aluminum phosphide (AlP)?", "answer": "For AlP the bonding is predominantly covalent (but with some ionic character) on the basis of the relative positions of Al and P in the periodic table.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释铝磷化合物(AlP)的键合类型，答案需要文字论述和解释，而不是选择、判断或计算。 | 知识层次: 题目要求根据元素周期表中铝和磷的相对位置判断AlP的键合类型，这需要理解元素电负性差异对键合性质的影响，并综合分析共价键和离子键的特征。虽然不涉及复杂计算，但需要对概念进行关联和综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生基于元素在周期表中的相对位置判断化学键类型，涉及对共价键和离子键概念的综合理解，以及元素电负性差异的分析。虽然不需要复杂的计算，但需要将多个知识点关联起来进行判断，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "predominantly covalent (but with some ionic character)", "choice_question": "What type of bonding would be expected for aluminum phosphide (AlP)?", "conversion_reason": "The answer is a standard description of the bonding type, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Predominantly covalent with some ionic character", "B": "Pure ionic bonding due to large electronegativity difference", "C": "Metallic bonding with partial covalent character", "D": "Mixed covalent and van der Waals bonding" }, "correct_answer": "A", "explanation": "The correct answer is A because AlP exhibits predominantly covalent bonding due to the moderate electronegativity difference (1.61 for Al vs 2.19 for P), but has some ionic character. Option B is a cognitive bias trap - while the electronegativity difference might suggest ionic bonding at first glance, the actual difference isn't large enough for pure ionic bonding. Option C exploits professional intuition by suggesting metallic bonding, which is incorrect for this semiconductor compound. Option D introduces an invalid van der Waals component, which doesn't apply to this strongly bonded compound.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4826, "question": "For the following pair of polymers, do the following: (1) state whether it is possible to determine whether one polymer has a higher melting temperature than the other; (2) if it is possible, note which has the higher melting temperature and then cite reason(s) for your choice; and (3) if it is not possible to decide, then state why. Polytetrafluoroethylene having a density of 2.14 g/cm3 and a weight-average molecular weight of 600,000 g/mol; PTFE having a density of 2.20 g/cm3 and a weight-average molecular weight of 600,000 g/mol", "answer": "Yes, it is possible to determine which polymer has the higher melting temperature. Of these two polytetrafluoroethylene polymers, the PTFE with the higher density (2.20 g/cm3) will have the higher percent crystallinity, and, therefore, a higher melting temperature than the lower density PTFE. The molecular weights of both materials are the same and, thus, molecular weight is not a consideration.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对两种聚合物的熔点进行比较，并解释原因。答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求比较两种聚合物的熔点，并解释原因。这涉及到对聚合物密度、分子量和结晶度之间关系的理解，以及这些因素如何影响熔点。虽然不需要复杂的计算，但需要综合分析多个因素（密度、分子量、结晶度）并理解它们之间的相互作用。这超出了简单记忆或直接套用的层次，属于中等应用水平。 | 难度: 在选择题中属于较高难度，需要综合理解聚合物密度、结晶度和熔融温度之间的关系，并进行多角度分析。题目要求比较两种PTFE的熔融温度，涉及密度和分子量的影响，需要考生能够关联多个概念并做出判断。虽然分子量相同，但密度的差异导致结晶度的不同，进而影响熔融温度。这种综合分析在选择题中属于较复杂的题目类型。", "convertible": true, "correct_option": "Yes, it is possible to determine which polymer has the higher melting temperature. Of these two polytetrafluoroethylene polymers, the PTFE with the higher density (2.20 g/cm3) will have the higher percent crystallinity, and, therefore, a higher melting temperature than the lower density PTFE. The molecular weights of both materials are the same and, thus, molecular weight is not a consideration.", "choice_question": "For the following pair of polymers, do the following: (1) state whether it is possible to determine whether one polymer has a higher melting temperature than the other; (2) if it is possible, note which has the higher melting temperature and then cite reason(s) for your choice; and (3) if it is not possible to decide, then state why. Polytetrafluoroethylene having a density of 2.14 g/cm3 and a weight-average molecular weight of 600,000 g/mol; PTFE having a density of 2.20 g/cm3 and a weight-average molecular weight of 600,000 g/mol", "conversion_reason": "The original short answer question can be converted into a multiple-choice question because the answer is a definitive statement that can be presented as a correct option among other plausible but incorrect options. The question format remains the same, but the answer is structured as a choice.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The PTFE with higher density (2.20 g/cm3) has higher melting temperature due to increased crystallinity", "B": "The PTFE with lower density (2.14 g/cm3) has higher melting temperature due to chain entanglement effects", "C": "Cannot be determined because molecular weight is the dominant factor for melting temperature", "D": "Both have identical melting temperatures since they are the same polymer with equal molecular weights" }, "correct_answer": "A", "explanation": "The correct answer is A because higher density in PTFE directly correlates with higher crystallinity, which increases melting temperature. Option B is wrong because chain entanglement affects mechanical properties more than melting point. Option C is a trap exploiting molecular weight being equal, but ignores density's role. Option D is incorrect because density differences indicate crystallinity variations that affect melting temperature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1815, "question": "Pauling's rules apply to (1)__ crystal structures.", "answer": "(1) ionic", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（ionic）来补全句子，属于需要简短文字回答的题目类型 | 知识层次: 题目考查对Pauling规则适用对象的基本概念记忆，属于基础概念记忆性知识 | 难度: 在选择题型中，此题仅考察对Pauling规则适用对象的基础记忆，属于最基础的定义简答级别。题目直接给出正确选项\"ionic\"，无需任何解释或分析步骤，完全依赖学生对基本概念的识记能力。", "convertible": true, "correct_option": "ionic", "choice_question": "Pauling's rules apply to which of the following crystal structures?", "conversion_reason": "The answer is a standard term (ionic), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ionic", "B": "covalent", "C": "metallic", "D": "molecular" }, "correct_answer": "A", "explanation": "Pauling's rules specifically apply to ionic crystal structures, as they govern the coordination and stability of ionic compounds. Option B (covalent) is a cognitive bias trap - while Pauling worked on covalent bonds, his rules don't apply here. Option C (metallic) exploits the common misconception that Pauling's work applies broadly to all bonding types. Option D (molecular) is designed to catch those who confuse crystal packing rules with Pauling's ionic structure rules.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 367, "question": "What is deformation texture?", "answer": "The deformation process causes the grains to rotate, and finally certain crystallographic directions within each grain tend to become parallel. This preferred orientation due to deformation is called deformation texture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"deformation texture\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即变形织构的定义和形成原因，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆\"deformation texture\"的定义和形成机制，需要掌握材料科学中关于晶体取向的基本概念。虽然涉及多个知识点（晶粒旋转、晶体学方向、择优取向），但整体仍属于单一概念的解释范畴，不需要进行复杂的概念体系分析或比较。在选择题型中，这属于中等偏基础的难度，比简单定义记忆稍复杂，但不及需要综合分析的多概念题目难度。", "convertible": true, "correct_option": "The deformation process causes the grains to rotate, and finally certain crystallographic directions within each grain tend to become parallel. This preferred orientation due to deformation is called deformation texture.", "choice_question": "Which of the following best defines deformation texture?", "conversion_reason": "The answer is a standard definition of a term, which can be presented as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The deformation process causes the grains to rotate, and finally certain crystallographic directions within each grain tend to become parallel. This preferred orientation due to deformation is called deformation texture.", "B": "The alignment of dislocations along specific slip systems during plastic deformation, which creates a characteristic pattern in the microstructure.", "C": "The residual stress distribution in a material after deformation, which affects the macroscopic texture observed by X-ray diffraction.", "D": "The statistical distribution of grain boundary misorientation angles that develops during severe plastic deformation processes." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines deformation texture as the preferred crystallographic orientation developed during deformation. Option B describes dislocation patterning, not texture. Option C confuses texture with residual stress. Option D describes grain boundary character distribution, which is a different microstructural feature. The distractors exploit common confusions between related but distinct concepts in deformation microstructures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2279, "question": "Calculate the critical length Lc of Al2O3 short fibers, given a diameter of 10μm, tensile strength of 2275MPa, and interfacial shear strength τy approximated by the matrix yield strength of 76MPa.", "answer": "For Al2O3 short fibers, the critical length Lc = (10×10^-6 × 2275) / (2 × 38) = 299.3×10^-6 m = 299.3μm. Since the actual length of 4mm is greater than Lc, the fibers can achieve maximum strengthening effect.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的参数（直径、拉伸强度、界面剪切强度）进行数值计算，应用公式求出临界长度Lc，答案也是具体的计算结果。整个过程符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，即使用给定的参数和公式计算临界长度Lc。虽然需要理解临界长度的概念，但整体思维过程较为直接，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅涉及单一公式的直接应用和简单计算，即使用临界长度公式 Lc = (d × σ) / (2 × τ) 进行计算。解题步骤简单，无需多个公式组合或复杂分析，属于最基础的难度等级。", "convertible": true, "correct_option": "299.3μm", "choice_question": "Calculate the critical length Lc of Al2O3 short fibers, given a diameter of 10μm, tensile strength of 2275MPa, and interfacial shear strength τy approximated by the matrix yield strength of 76MPa. The critical length Lc is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "299.3μm", "B": "149.7μm", "C": "598.6μm", "D": "75.0μm" }, "correct_answer": "A", "explanation": "The correct answer is A (299.3μm) calculated using Lc = (σf × d)/(2τy) = (2275 × 10)/(2 × 76). Option B (149.7μm) is a common error from forgetting to divide by 2 in the formula. Option C (598.6μm) results from incorrectly doubling the correct value. Option D (75.0μm) exploits confusion between fiber diameter and critical length by using the matrix yield strength directly.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 27, "question": "According to the radius ratio rule, what is the coordination number when Mg2+ coordinates with O2-? Given rO2-=0.132nm, rMg2+=0.078nm.", "answer": "For Mg2+, r+/r-=0.078/0.132=0.59; based on the relationship between cation coordination number and cation-anion radius ratio, the coordination number is 6.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求根据给定的离子半径计算半径比，并应用半径比规则确定配位数。解答过程涉及数值计算和公式应用。 | 知识层次: 题目需要应用半径比规则进行简单的数值计算，并直接套用已知的半径比与配位数关系表得出结果。虽然涉及基本概念的理解，但主要考察的是基本公式的直接应用和简单计算能力，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用半径比规则进行计算，但仅涉及单一公式的直接套用和简单除法运算，无需多个步骤或复杂分析。因此，在选择题型内属于较低难度等级。", "convertible": true, "correct_option": "6", "choice_question": "According to the radius ratio rule, what is the coordination number when Mg2+ coordinates with O2-? Given rO2-=0.132nm, rMg2+=0.078nm.", "conversion_reason": "The answer is a specific numerical value (6), which can be presented as a choice in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6", "B": "选项D", "C": "选项B", "D": "选项C" }, "correct_answer": "A", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1767, "question": "In the wetting of solid-liquid interfaces, one of the methods to improve wetting is?", "answer": "Reduce the solid-liquid interfacial energy", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释一种改善润湿的方法，答案需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查的是关于固体-液体界面润湿改进方法的基本概念记忆，即通过降低固液界面能来改善润湿性。这属于基础概念的记忆和理解范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即\"降低固液界面能\"这一改善润湿性的方法。题目不涉及概念解释或复杂体系分析，属于最基础的定义简答级别。", "convertible": true, "correct_option": "Reduce the solid-liquid interfacial energy", "choice_question": "In the wetting of solid-liquid interfaces, which of the following methods can improve wetting?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Reduce the solid-liquid interfacial energy", "B": "Increase the surface roughness of the solid", "C": "Apply an external electric field perpendicular to the interface", "D": "Decrease the viscosity of the liquid" }, "correct_answer": "A", "explanation": "Reducing the solid-liquid interfacial energy directly improves wetting by lowering the energy barrier for spreading. Option B is misleading because while roughness can enhance apparent wetting, it doesn't fundamentally improve intrinsic wettability. Option C exploits the common misconception that electric fields always improve wetting, but perpendicular fields actually disrupt interfacial bonding. Option D plays on the intuitive but incorrect link between viscosity and wetting kinetics, when in fact viscosity only affects spreading rate not equilibrium wettability.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1973, "question": "In the <100> direction of copper (fcc, a=0.361nm), what is the linear density of atoms?", "answer": "The linear density of Cu atoms is 2.77×10^6 atoms/mm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算铜在<100>方向上的线性原子密度，需要应用晶体结构参数和公式进行数值计算，答案给出了具体的计算结果。 | 知识层次: 题目需要应用基本的线性密度计算公式，并代入给定的晶格常数进行计算，属于直接套用公式的简单应用层次。虽然需要理解晶向和晶格结构的基本概念，但整体思维过程较为直接，不涉及多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算铜在<100>方向的线性原子密度，仅需应用线性密度的基本公式（1/a）并进行单位转换（从nm到mm），无需复杂的推导或多步骤计算。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "2.77×10^6 atoms/mm", "choice_question": "In the <100> direction of copper (fcc, a=0.361nm), what is the linear density of atoms?", "conversion_reason": "计算题的答案是确定的数值，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.77×10^6 atoms/mm", "B": "1.39×10^6 atoms/mm", "C": "5.54×10^6 atoms/mm", "D": "3.92×10^6 atoms/mm" }, "correct_answer": "A", "explanation": "The correct answer is A (2.77×10^6 atoms/mm) because in the <100> direction of an FCC crystal like copper, there is 1 atom per lattice parameter (a=0.361nm). Linear density = 1 atom / 0.361nm = 2.77×10^6 atoms/mm. Option B (1.39×10^6 atoms/mm) is a common error from incorrectly dividing by 2a, creating a cognitive bias trap. Option C (5.54×10^6 atoms/mm) doubles the correct value, exploiting unit conversion errors. Option D (3.92×10^6 atoms/mm) uses √2/a, which is the <110> direction density, a professional intuition trap confusing different crystallographic directions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1979, "question": "Nickel has a face-centered cubic structure with an atomic radius of r_Ni=0.1246 nm. Determine the number of atoms per 1 mm^2 on the (110) plane of nickel.", "answer": "1.14×10^13 atoms/mm^2", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定镍在(110)平面上每平方毫米的原子数，答案是一个具体的数值结果，解答过程需要涉及晶体结构参数的计算。 | 知识层次: 题目需要多步计算和概念关联，包括晶体结构、晶面原子密度计算等综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解面心立方结构、(110)晶面的原子排列、原子半径与晶格参数的关系，并进行多步计算（晶格参数计算、面密度计算、单位换算）。虽然选项已给出，但解题过程涉及多个概念的综合应用和单位转换，属于综合性计算问题。", "convertible": true, "correct_option": "1.14×10^13 atoms/mm^2", "choice_question": "Nickel has a face-centered cubic structure with an atomic radius of r_Ni=0.1246 nm. Determine the number of atoms per 1 mm^2 on the (110) plane of nickel.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.14×10^13 atoms/mm^2", "B": "9.21×10^12 atoms/mm^2", "C": "1.62×10^13 atoms/mm^2", "D": "8.47×10^12 atoms/mm^2" }, "correct_answer": "A", "explanation": "The correct answer A is derived from calculating the planar density of the (110) plane in FCC nickel. The (110) plane contains 2 atoms per area of a√2 × a, where a=4r/√2. Option B is calculated by incorrectly using the (100) plane density. Option C results from miscalculating the lattice parameter as 2r instead of 4r/√2. Option D comes from an incorrect assumption about atomic packing on the (110) plane, counting only 1 atom per unit area.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4660, "question": "The unit cell for uranium (U) has orthorhombic symmetry, with a, b, and c lattice parameters of 0.286,0.587, and 0.495nm, respectively. If its density, atomic weight, and atomic radius are 19.05g / {cm}^{3}, 238.03g / mol, and 0.1385nm, respectively, compute the atomic packing factor.\n\\title{", "answer": "the atomic packing factor (apf) for uranium is 0.536.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铀的原子堆积因子（APF），答案是一个具体的数值结果（0.536），解答过程需要运用密度、原子重量、晶格参数等数据进行计算。 | 知识层次: 题目需要计算原子堆积因子（APF），这涉及到多步计算和概念关联。首先需要理解APF的定义（体积分数），然后计算晶胞体积和原子总体积。计算过程中需要应用晶格参数、原子半径和密度等数据，并进行单位转换和综合分析。虽然不涉及复杂的推理或创新设计，但需要一定的计算步骤和概念整合。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如晶胞参数、密度、原子量、原子半径等）并进行多步骤计算（如计算晶胞体积、原子体积、原子数等），最终综合得出原子堆积因子。虽然题目提供了所有必要参数，但计算过程涉及多个步骤和概念的综合应用，对学生的理解和计算能力有一定要求。", "convertible": true, "correct_option": "0.536", "choice_question": "The unit cell for uranium (U) has orthorhombic symmetry, with a, b, and c lattice parameters of 0.286, 0.587, and 0.495 nm, respectively. If its density, atomic weight, and atomic radius are 19.05 g/cm³, 238.03 g/mol, and 0.1385 nm, respectively, what is the atomic packing factor for uranium?", "conversion_reason": "The question is a calculation problem with a specific numerical answer (0.536), which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.536", "B": "0.623", "C": "0.487", "D": "0.682" }, "correct_answer": "A", "explanation": "The correct answer is A (0.536) because it is calculated by dividing the volume of atoms in the unit cell by the volume of the unit cell itself, considering orthorhombic symmetry and given parameters. Option B (0.623) is a common FCC packing factor, exploiting the AI's tendency to default to common crystal structures. Option C (0.487) mimics a BCC packing factor, another common structure that might be incorrectly assumed. Option D (0.682) represents the theoretical maximum packing factor (for HCP/FCC), playing on the AI's potential to overestimate based on ideal scenarios rather than actual given data.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4903, "question": "For the cadmium and zinc pair that are coupled in seawater, predict the possibility of corrosion; if corrosion is probable, note which metal/alloy will corrode.", "answer": "For the cadmium-zinc couple, corrosion is possible, and zinc will corrode.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求预测腐蚀可能性并指出哪种金属会腐蚀，需要文字解释和论述，答案也是以文字形式给出，没有选项或计算要求。 | 知识层次: 题目需要应用基本的电化学腐蚀原理（如电偶腐蚀）来判断金属对的腐蚀行为，属于直接套用基础知识的简单应用，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接套用基本的腐蚀原理知识（如电偶序）即可得出答案。解题步骤简单，无需复杂计算或多概念综合分析，符合等级2的简单应用过程描述标准。", "convertible": true, "correct_option": "For the cadmium-zinc couple, corrosion is possible, and zinc will corrode.", "choice_question": "For the cadmium and zinc pair that are coupled in seawater, predict the possibility of corrosion; if corrosion is probable, note which metal/alloy will corrode.", "conversion_reason": "The answer is a standard and specific statement that can be directly used as a correct option in a multiple-choice question. The question can remain as is, with the answer serving as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Corrosion is possible, and zinc will corrode due to its lower standard electrode potential (-0.76V) compared to cadmium (-0.40V)", "B": "Corrosion is possible, but cadmium will corrode because it's more reactive in seawater environments", "C": "No corrosion will occur because both metals are amphoteric and form protective oxide layers in seawater", "D": "Corrosion is possible, but the direction depends on the relative surface areas of the two metals" }, "correct_answer": "A", "explanation": "The correct answer is A because zinc has a more negative standard electrode potential than cadmium, making it the anode in this galvanic couple. Option B is a cognitive bias trap - while cadmium is more reactive in some contexts, its nobility in seawater is well documented. Option C exploits surface science intuition by referencing true amphoteric behavior but ignoring the galvanic potential difference. Option D is a multi-parameter trap - while surface area ratios do affect corrosion rates, they don't reverse the fundamental potential difference in this system.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4280, "question": "The critical resolved shear stress for iron is 27 MPa(4000 psi). Determine the maximum possible yield strength for a single crystal of \\mathrm{Fe} pulled in tension.", "answer": "the maximum possible yield strength for a single crystal of \\mathrm{fe} pulled in tension is 54 MPa (8000 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过计算确定单晶铁在拉伸条件下的最大可能屈服强度，需要使用临界分切应力和相关公式进行计算。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用临界分切应力的基本概念和公式进行简单计算，属于直接套用基本公式的应用层次。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求应用临界分切应力与屈服强度的基本关系公式（τ = σ/2），只需简单代入给定数值进行计算即可得出答案。无需复杂推导或多步骤分析，属于最基础的应用题类型。", "convertible": true, "correct_option": "54 MPa (8000 psi)", "choice_question": "The critical resolved shear stress for iron is 27 MPa(4000 psi). What is the maximum possible yield strength for a single crystal of \\mathrm{Fe} pulled in tension?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "54 MPa (8000 psi)", "B": "27 MPa (4000 psi)", "C": "81 MPa (12000 psi)", "D": "108 MPa (16000 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A because the maximum yield strength occurs when the slip plane is oriented at 45° to the tensile axis, requiring twice the critical resolved shear stress (2×27 MPa = 54 MPa). Option B is a cognitive bias trap using the raw shear stress value. Option C exploits a common error of multiplying by 3 instead of 2. Option D is a multi-layer trap combining both the 2× multiplier and an incorrect assumption of needing to double the result again for safety.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1134, "question": "What is the movement of dislocations perpendicular to the slip plane called?", "answer": "Climb", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字回答一个特定的概念（dislocation movement perpendicular to slip plane），答案是一个术语（Climb），不需要选择、判断或计算 | 知识层次: 题目考查基本概念的记忆和理解，即位错运动中的\"攀移\"（climb）这一术语的定义。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即对\"dislocation movement perpendicular to the slip plane\"这一特定术语的定义记忆。题目直接询问专业术语名称，不涉及概念解释或复杂分析，属于最基本的知识点考察。", "convertible": true, "correct_option": "Climb", "choice_question": "What is the movement of dislocations perpendicular to the slip plane called?", "conversion_reason": "The answer is a standard term in the field of materials science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Climb", "B": "Cross-slip", "C": "Glide", "D": "Twist" }, "correct_answer": "A", "explanation": "The correct answer is 'Climb' because dislocation movement perpendicular to the slip plane requires diffusion of vacancies or interstitials, which is the definition of climb. 'Cross-slip' (B) is incorrect as it refers to dislocations moving from one slip plane to another parallel plane. 'Glide' (C) is incorrect as it describes dislocation motion within the slip plane. 'Twist' (D) is incorrect as it refers to a type of grain boundary, not dislocation motion. The distractors exploit common confusion between different types of dislocation movements and their geometric relationships to slip planes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 560, "question": "What are the factors affecting atomic diffusion in crystalline solids? Briefly explain the influence of crystal defects.", "answer": "Crystal defects. The diffusion coefficient along grain boundaries is much larger than that of bulk diffusion; the activation energy for diffusion along dislocation pipes is smaller, thus dislocations accelerate diffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释影响原子扩散的因素，并简要说明晶体缺陷的影响。答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释影响原子扩散的因素，并具体分析晶体缺陷的影响。这需要理解扩散的基本原理，并将这些原理与晶体缺陷的特性关联起来，进行综合分析。虽然不涉及复杂计算，但需要多步概念关联和一定程度的综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解晶体缺陷对原子扩散的影响，并能够比较不同缺陷类型（如晶界和位错）对扩散系数和活化能的具体影响。虽然题目涉及多个概念的综合分析，但在选择题型中，正确选项已经提供了明确的比较和结论，降低了答题的复杂性。", "convertible": true, "correct_option": "Crystal defects", "choice_question": "Which of the following factors significantly affects atomic diffusion in crystalline solids by increasing the diffusion coefficient along grain boundaries and reducing activation energy for diffusion along dislocation pipes?", "conversion_reason": "The answer is a standard term (Crystal defects) and the question can be rephrased to fit a multiple-choice format by focusing on the key concept.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystal defects", "B": "Elastic modulus", "C": "Thermal conductivity", "D": "Surface roughness" }, "correct_answer": "A", "explanation": "Crystal defects like grain boundaries and dislocations create pathways for enhanced atomic diffusion by increasing the diffusion coefficient and reducing activation energy. Option B (Elastic modulus) is a cognitive bias trap - while related to atomic bonding, it doesn't directly govern diffusion kinetics. Option C (Thermal conductivity) is a multi-level verification trap - it affects heat transfer but not atomic mobility mechanisms. Option D (Surface roughness) is a professional intuition trap - it influences surface phenomena but not bulk diffusion processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1606, "question": "What is the difference between the effects of slip and twinning, these two metal plastic deformation mechanisms, on the crystal orientation relationship?", "answer": "The twinning process alters the crystal orientation relationship. The slip process does not change the crystal orientation relationship.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两种金属塑性变形机制（滑移和孪生）对晶体取向关系的影响差异，答案以文字形式进行论述和比较，符合简答题的特征。 | 知识层次: 题目考查对金属塑性变形机制（滑移和孪生）对晶体取向关系影响的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（滑移和孪生两种金属塑性变形机制），但需要考生理解并区分这两种机制对晶体取向关系的具体影响。正确选项明确指出了孪生过程会改变晶体取向关系而滑移过程不会，这要求考生不仅要记住定义，还要能够比较和区分两种机制的效果。因此，该题目在选择题型内属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "The twinning process alters the crystal orientation relationship. The slip process does not change the crystal orientation relationship.", "choice_question": "What is the difference between the effects of slip and twinning, these two metal plastic deformation mechanisms, on the crystal orientation relationship?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Twinning creates a mirror-image orientation while slip preserves the original orientation", "B": "Both mechanisms equally alter the crystal orientation through dislocation movement", "C": "Slip causes greater orientation change due to cumulative dislocation motion", "D": "Neither mechanism affects orientation as deformation occurs along crystallographic planes" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the fundamental difference: twinning creates a mirrored crystal orientation while slip preserves the original orientation through dislocation glide. Option B is a cognitive bias trap, incorrectly equating the mechanisms. Option C reverses the truth, exploiting the intuition that cumulative effects should matter more. Option D is a professional intuition trap, using correct terminology about crystallographic planes but drawing the wrong conclusion about orientation effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2233, "question": "Determine whether the following statement is correct. (6) The melting point of 20# steel is lower than that of pure iron, so its recrystallization temperature is also lower than that of pure iron.", "answer": "Incorrect. The presence of trace solute atoms (wC=0.002 in 20# steel) hinders the recrystallization of the metal, thereby increasing its recrystallization temperature.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断陈述的对错，答案明确指出\"Incorrect\"并给出解释，符合判断题的特征 | 知识层次: 题目需要理解合金元素对金属性能的影响，并能够将溶质原子对再结晶温度的阻碍作用与熔点变化的影响进行综合分析。这涉及到多个概念的关联和一定程度的推理分析，超出了简单记忆或直接套用的层次。 | 难度: 在选择题中属于较高难度，需要综合分析多个概念（熔点、再结晶温度、溶质原子影响）并进行逻辑推理判断正误。题目不仅考察基础概念理解，还要求考生掌握溶质原子对金属再结晶行为的复杂影响机制，属于中等应用层次的多步骤综合分析题。", "convertible": true, "correct_option": "Incorrect. The presence of trace solute atoms (wC=0.002 in 20# steel) hinders the recrystallization of the metal, thereby increasing its recrystallization temperature.", "choice_question": "Determine whether the following statement is correct. (6) The melting point of 20# steel is lower than that of pure iron, so its recrystallization temperature is also lower than that of pure iron.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All solid solutions exhibit higher recrystallization temperatures than their pure metal counterparts due to solute atom pinning effects.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While solute atoms generally hinder dislocation movement and increase recrystallization temperature, this is not universally true for all solid solutions. The effect depends on factors like solute concentration, atomic size mismatch, and bonding characteristics. Some dilute solid solutions may show negligible or even opposite effects under certain conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4272, "question": "For edge dislocation, cite the relationship between the direction of the applied shear stress and the direction of dislocation line motion.", "answer": "edge dislocation--parallel", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和论述边缘位错中施加的剪切应力方向与位错线运动方向之间的关系，答案需要文字描述而非选择、判断或计算。 | 知识层次: 题目考查对刃位错基本概念的记忆和理解，只需要记住刃位错线运动方向与外加剪切应力方向的关系即可回答，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即刃位错中施加剪切应力方向与位错线运动方向的关系。题目直接给出正确选项\"parallel\"，无需任何解释或分析步骤，属于最简单的定义性知识考查。", "convertible": true, "correct_option": "parallel", "choice_question": "For edge dislocation, what is the relationship between the direction of the applied shear stress and the direction of dislocation line motion?", "conversion_reason": "The answer is a standard term that can be presented as a choice among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Parallel", "B": "Perpendicular", "C": "45-degree angle", "D": "Stress direction has no effect on dislocation motion" }, "correct_answer": "A", "explanation": "For edge dislocations, the direction of dislocation line motion is parallel to the applied shear stress direction due to the nature of the Burgers vector orientation. Option B exploits the common confusion with screw dislocations where motion is perpendicular. Option C capitalizes on the visual similarity to slip plane angles. Option D targets misconceptions about dislocation pinning effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 758, "question": "Briefly describe the characteristics of secondary recrystallization", "answer": "Characteristics of secondary recrystallization: it is an abnormal growth process where a few large grains grow at the expense of fine grains. It involves the abnormal growth of individual grains; during secondary recrystallization, pores are enclosed within the grains; secondary recrystallization is also related to the particle size of the raw material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述二次再结晶的特征，答案以文字解释和论述的形式呈现，没有涉及选择、判断或计算。 | 知识层次: 题目考查对二次再结晶特性的基本概念记忆和理解，涉及定义和简单描述，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生对二次再结晶的特征进行描述，涉及多个关键点（异常生长过程、大晶粒消耗小晶粒、孔隙被包裹、与原料粒径的关系）。虽然需要记忆和理解多个概念，但不需要复杂的分析或比较，属于概念解释和描述的难度层次。", "convertible": true, "correct_option": "Characteristics of secondary recrystallization: it is an abnormal growth process where a few large grains grow at the expense of fine grains. It involves the abnormal growth of individual grains; during secondary recrystallization, pores are enclosed within the grains; secondary recrystallization is also related to the particle size of the raw material.", "choice_question": "Which of the following best describes the characteristics of secondary recrystallization?", "conversion_reason": "The answer is a standard description of the characteristics of secondary recrystallization, which can be presented as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Abnormal growth of individual grains consuming finer matrix grains, with pores becoming trapped inside growing grains", "B": "Uniform grain growth driven solely by reduction of grain boundary energy, maintaining equiaxed grain structure", "C": "Simultaneous nucleation and growth of new grains throughout the material, similar to primary recrystallization", "D": "Selective growth of grains with specific crystallographic orientations due to applied stress or strain" }, "correct_answer": "A", "explanation": "Correct answer A describes the key features of secondary recrystallization: abnormal growth of select grains, consumption of finer grains, and pore entrapment. Option B is incorrect because it describes normal grain growth, not abnormal growth. Option C is a trap for confusing secondary with primary recrystallization. Option D exploits the intuition that orientation might play a role, but describes texture development rather than secondary recrystallization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2550, "question": "Given that the outer surface of a copper single crystal sample is (111), analyze the possible angles between slip lines that may appear on this outer surface when the crystal undergoes slip at room temperature.", "answer": "The possible slip planes are the {111} family of crystal planes, and their intersections with the (111) plane may be [ 10], [0 1], [10 ], so the slip lines are either parallel or at a 60-degree angle to each other.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析铜单晶样品在特定条件下可能出现的滑移线角度，需要基于晶体学知识进行解释和论述，答案也以文字解释形式给出，没有涉及计算或选择判断。 | 知识层次: 题目要求分析铜单晶样品在特定表面(111)上可能出现的滑移线角度，需要理解晶体滑移的基本原理（{111}滑移面族），并能将滑移面与特定表面相交的情况进行综合分析。这涉及多步概念关联和几何分析，但不需要复杂的机理或创新应用。 | 难度: 在选择题型中，该题目属于较高难度。首先，需要理解晶体滑移的基本概念，包括滑移面和滑移方向。其次，需要掌握立方晶系中{111}晶面族的几何特性及其与给定(111)表面的交线计算。最后，还需要综合分析滑移线在表面上的可能角度关系。这些步骤涉及多步计算和概念关联，超出了简单的记忆或单一概念应用，属于中等应用层次中的复杂综合分析。", "convertible": true, "correct_option": "The slip lines are either parallel or at a 60-degree angle to each other.", "choice_question": "Given that the outer surface of a copper single crystal sample is (111), what are the possible angles between slip lines that may appear on this outer surface when the crystal undergoes slip at room temperature?", "conversion_reason": "The answer is a standard and specific description that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the possible angles between slip lines.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The slip lines are either parallel or at a 60-degree angle to each other", "B": "The slip lines can form any angle between 0° and 90° due to multiple slip systems", "C": "The slip lines will always be at 120° angles due to the hexagonal symmetry of the (111) plane", "D": "The angle between slip lines is determined by the ratio of Schmid factors and can vary continuously" }, "correct_answer": "A", "explanation": "The correct answer is A because copper has FCC structure with {111}<110> slip systems. On a (111) surface, slip traces from different {111} planes will intersect at either 0° (parallel) or 60° angles. Option B is a cognitive bias trap, incorrectly suggesting continuous angular variation. Option C exploits symmetry misconception by implying hexagonal symmetry applies to slip traces. Option D is a sophisticated trap using valid Schmid factor concept but misapplying it to slip trace angles.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4731, "question": "Compare interstitial and vacancy atomic mechanisms for diffusion.", "answer": "With vacancy diffusion, atomic motion is from one lattice site to an adjacent vacancy. Self-diffusion and the diffusion of substitutional impurities proceed via this mechanism. On the other hand, atomic motion is from interstitial site to adjacent interstitial site for the interstitial diffusion mechanism.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较两种扩散机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对间隙扩散和空位扩散两种原子扩散机制的基本概念的理解和记忆，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目要求考生理解和比较两种不同的扩散机制（间隙扩散和空位扩散），并能够描述它们的基本原理和区别。虽然涉及多个概念，但题目提供了明确的定义和分类，属于概念解释和描述的层次，不需要进行复杂的体系阐述或深入分析。因此，难度等级为2。", "convertible": true, "correct_option": "With vacancy diffusion, atomic motion is from one lattice site to an adjacent vacancy. Self-diffusion and the diffusion of substitutional impurities proceed via this mechanism. On the other hand, atomic motion is from interstitial site to adjacent interstitial site for the interstitial diffusion mechanism.", "choice_question": "Compare interstitial and vacancy atomic mechanisms for diffusion. Which of the following statements is correct?", "conversion_reason": "The answer is a standard explanation of the two diffusion mechanisms, which can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct statement among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Vacancy diffusion requires higher activation energy than interstitial diffusion due to lattice distortion", "B": "Interstitial diffusion is the dominant mechanism for substitutional alloying elements in FCC metals", "C": "Both mechanisms exhibit the same temperature dependence as described by the Arrhenius equation", "D": "Vacancy diffusion becomes negligible above the Debye temperature of the material" }, "correct_answer": "A", "explanation": "Correct answer A is accurate because vacancy diffusion indeed requires higher activation energy due to the need to break more bonds and create lattice distortion. Option B is a cognitive bias trap - while true for interstitial elements, substitutional elements diffuse via vacancies. Option C is a professional intuition trap - while both follow Arrhenius behavior, their pre-exponential factors differ significantly. Option D is a multi-level verification trap - vacancy diffusion remains important above Debye temperature as it's governed by vacancy concentration.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2354, "question": "(2) Calculate the theoretical density of CsCl.", "answer": "First, calculate the lattice constant from the ionic radii. Since the crystal structure is simple cubic, the diagonal length of the cube should be the sum of the diameters of the negative and positive ions, i.e., equal to $2(0.181+0.165)\\\\mathrm{nm}=0.692$ nm. The diagonal length equals $\\\\sqrt{3}a$, so $a=0.692/\\\\sqrt{3}=0.3995$ nm. From the appendix, the relative atomic masses of Cl and Cs are $35.45$ and $132.91$, respectively. The mass of each Cl and Cs atom is $35.45/6.023\\\\times10^{23}=5.885\\\\times10^{-23}$ g and $132.91/6.023\\\\times10^{23}=2.207\\\\times10^{-22}$ g. A unit cell contains one Cl ion and one Cs ion, so the theoretical density of CsCl is $\\\\rho_{\\\\text{(CsCl)}}=\\\\frac{5.885\\\\times10^{-23}+2.207\\\\times10^{-22}}{(0.3995\\\\times10^{-7})^{3}}\\\\text{g/cm}^{3}=4.38\\\\text{g/cm}^{3}$. The calculated theoretical density is slightly higher than the experimentally measured density, possibly because the estimated lattice constant is smaller than the actual value.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解CsCl的理论密度，解答过程中涉及多个计算步骤和公式推导，最终得出具体数值结果。 | 知识层次: 题目需要进行多步计算，包括从离子半径计算晶格常数、利用相对原子质量计算单个原子的质量、结合单位晶胞中的原子数计算理论密度，并涉及简单的误差分析。虽然不涉及复杂的综合分析或创新应用，但需要多个概念和公式的关联应用，超出了简单直接套用的层次。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、离子半径、晶格常数计算、相对原子质量转换、密度公式应用等多个概念，并进行多步骤的综合计算。虽然题目提供了完整的解题步骤，但在选择题型中需要考生快速识别关键计算点并验证结果，对知识掌握和计算能力要求较高。", "convertible": true, "correct_option": "4.38 g/cm³", "choice_question": "What is the theoretical density of CsCl?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible but incorrect values.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.38 g/cm³", "B": "3.99 g/cm³", "C": "4.02 g/cm³", "D": "4.15 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer is A (4.38 g/cm³) because it is the theoretical density calculated using the unit cell parameters and atomic weights of CsCl. Option B (3.99 g/cm³) is a common error from misapplying the coordination number calculation. Option C (4.02 g/cm³) exploits the tendency to confuse CsCl with similar ionic compounds like NaCl. Option D (4.15 g/cm³) is designed to trap those who incorrectly account for packing efficiency in BCC structures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2991, "question": "Thermosetting plastics mainly have (5) molecular chains.", "answer": "(5) three-dimensional network", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（three-dimensional network）来描述热固性塑料的分子链结构，属于需要特定关键词回答的简答题形式 | 知识层次: 题目考查热固性塑料分子链结构的基本概念记忆，属于定义性知识，无需复杂分析或应用。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需考生回忆并识别热固性塑料的主要分子链结构（三维网络）。题目仅涉及单一知识点的直接回忆，无需解释或分析，属于选择题中最简单的难度等级。", "convertible": true, "correct_option": "three-dimensional network", "choice_question": "Thermosetting plastics mainly have which type of molecular chains?", "conversion_reason": "The answer is a standard term that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "three-dimensional network", "B": "linear with occasional cross-linking", "C": "branched polymer chains", "D": "semi-crystalline lamellae" }, "correct_answer": "A", "explanation": "Thermosetting plastics form irreversible three-dimensional networks during curing (A). B exploits the confusion with thermoplastic elastomers that have limited cross-linking. C targets the misconception that all rigid polymers must be branched. D is a crystalline structure trap that applies to some thermoplastics but not thermosets.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2196, "question": "A subgrain boundary is composed of several edge dislocations with a misorientation of 0.057 degrees. Assuming there is no interaction between the dislocations before polygonization, by what factor does the distortion energy change after the formation of the subgrain?", "answer": "The energy per unit length of a dislocation line is W_I = (G b^2) / (4π(1-ν)) * ln(R/r_0), where r_0 is the radius of the dislocation core region and R is the radius of the maximum range of the dislocation stress field. If we take r_0 ≈ b = 10^-8 cm and R ≈ 10^-4 cm, then before polygonization, W_D = (G b^2) / (4π(1-ν)) * ln(10^4). After polygonization, R = D = b / θ = 10^-8 / 10^-3 = 10^-5 cm, and W_31* = (G b^2) / (4π(1-ν)) * ln(10^3). Thus, W_I* / W_I1 = ln(10^3) / ln(10^4) = 0.75.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解亚晶界形成后畸变能的变化因子，答案中包含了具体的公式推导和数值计算过程。 | 知识层次: 题目需要进行多步计算，涉及位错能量公式的应用和变形前后的能量比较，需要理解位错的基本概念和能量计算原理，并进行综合分析。虽然不涉及复杂的机理分析或创新应用，但计算过程需要一定的思维深度和概念关联。 | 难度: 在选择题中属于中等偏上难度，需要理解位错能量公式、多边形化过程以及角度与距离的转换关系。题目涉及多步骤计算（如计算前后能量比）和概念关联（如位错核心半径与应力场范围的关系），但未达到复杂多变量计算的程度。", "convertible": true, "correct_option": "0.75", "choice_question": "A subgrain boundary is composed of several edge dislocations with a misorientation of 0.057 degrees. Assuming there is no interaction between the dislocations before polygonization, by what factor does the distortion energy change after the formation of the subgrain?", "conversion_reason": "The answer is a specific numerical value (0.75), which can be directly used as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.75", "B": "1.33", "C": "0.50", "D": "2.00" }, "correct_answer": "A", "explanation": "The correct answer is 0.75 because the distortion energy of a subgrain boundary is reduced to 75% of the total energy of isolated dislocations due to mutual cancellation of strain fields. Option B (1.33) exploits the inverse relationship misconception. Option C (0.50) traps those who overestimate energy reduction. Option D (2.00) targets confusion with energy doubling in certain dislocation interactions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1873, "question": "Most solid-phase reactions fall into A. Chemical reaction kinetics range B. Diffusion kinetics range C. Transition range", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项A、B、C中选择正确答案 | 知识层次: 题目考查对固相反应动力学范围的基本分类记忆，属于基础概念的记忆和理解层面，不需要复杂的分析或应用过程。 | 难度: 在选择题型中，此题属于基础概念记忆类型，仅需识别\"Most solid-phase reactions\"的分类归属。题目直接考察对固相反应动力学范围的基本定义记忆，无需复杂辨析或深度理解。正确选项B（Diffusion kinetics range）是教材中明确指出的标准答案，属于简单概念识别层级。", "convertible": true, "correct_option": "B. Diffusion kinetics range", "choice_question": "Most solid-phase reactions fall into:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chemical reaction kinetics range (due to strong covalent bonding in solids)", "B": "Diffusion kinetics range", "C": "Transition range (where both reaction and diffusion effects are comparable)", "D": "Surface-controlled kinetics range (due to limited active sites on solid surfaces)" }, "correct_answer": "B", "explanation": "The correct answer is B because solid-phase reactions are typically limited by the slow diffusion of atoms/ions through the crystal lattice. Option A exploits the cognitive bias that strong bonding implies reaction control, while in reality bonding strength doesn't determine rate-limiting step. Option C creates a false transitional zone that doesn't exist in classical kinetics theory. Option D strategically misapplies surface chemistry concepts that are more relevant to gas-solid reactions than bulk solid-state reactions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4336, "question": "Compute the mass fraction of pearlite that forms in an iron-carbon alloy containing 0.25 wt% C.", "answer": "the mass fraction of pearlite is 0.31.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解珠光体的质量分数，答案是一个具体的数值结果（0.31），这表明需要进行计算过程。 | 知识层次: 题目涉及基本的铁碳合金相图知识，需要应用杠杆定律进行简单的质量分数计算，属于基本公式的直接应用，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用杠杆法则（lever rule）这一单一公式进行计算，属于基本公式的直接套用。解题步骤简单，仅需代入给定数值即可得出结果，无需复杂的推理或多步骤计算。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "0.31", "choice_question": "What is the mass fraction of pearlite that forms in an iron-carbon alloy containing 0.25 wt% C?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.31", "B": "0.25", "C": "0.42", "D": "0.17" }, "correct_answer": "A", "explanation": "The correct answer is A (0.31) because it is calculated using the lever rule with the eutectoid composition (0.76 wt% C) and the given alloy composition (0.25 wt% C). Option B (0.25) is a cognitive bias trap, directly using the carbon content without proper calculation. Option C (0.42) is a professional intuition trap, incorrectly assuming a linear relationship between carbon content and pearlite fraction. Option D (0.17) is a multi-level verification trap, mistakenly using the proeutectoid ferrite fraction instead of pearlite.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4620, "question": "Can a material have an index of refraction less than unity? Why or why not?", "answer": "In order for a material to have an index of refraction less than unity, the velocity of light in the material (v) would necessarily have to be greater than the velocity of light in a vacuum. This is not possible.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对材料折射率小于1的可能性进行解释和论述，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对折射率基本概念的理解，涉及光速在介质中的传播速度与真空中的比较，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及折射率的基本定义，但需要考生理解折射率与光速的关系，并能够推理出折射率小于1的情况在物理上不可能的原因。这超出了简单的定义记忆，需要对概念进行解释和描述。", "convertible": true, "correct_option": "In order for a material to have an index of refraction less than unity, the velocity of light in the material (v) would necessarily have to be greater than the velocity of light in a vacuum. This is not possible.", "choice_question": "Can a material have an index of refraction less than unity? Why or why not?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because the speed of light in a material cannot exceed its speed in vacuum", "B": "Yes, in metamaterials with engineered negative permittivity and permeability", "C": "Yes, near absorption resonances where the phase velocity can exceed c", "D": "No, because all materials slow down electromagnetic waves" }, "correct_answer": "A", "explanation": "Correct answer A is based on fundamental physics: refractive index n=c/v, so n<1 would require v>c which violates relativity. Distractors exploit subtle nuances: B is wrong because negative index materials still have n>1 magnitude (just negative sign). C is wrong because while phase velocity can exceed c, signal velocity cannot. D is wrong because some materials (like ionized gases) can have n<1 for certain frequencies while still obeying v 90°, cannot wet. To silver plate ceramic components, the surface of the ceramic must first be ground and polished to improve the wettability between the ceramic and the silver layer.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释液态银是否能润湿氧化铝陶瓷表面，并提出改善润湿性的方法。答案包含计算过程和文字解释，属于需要论述的简答题类型。 | 知识层次: 题目需要应用表面张力的基本公式计算接触角，并理解润湿性的判断标准（θ > 90°为不润湿）。此外，还需要提出改善润湿性的方法，涉及多步分析和概念关联。虽然计算部分相对简单，但整体需要综合分析表面处理和润湿性改善的关系。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及表面能的计算和润湿角的概念，要求考生能够正确应用公式计算润湿角，并根据结果判断润湿性。此外，还需要理解如何通过物理方法改善润湿性。虽然题目涉及多步计算和概念关联，但在选择题型中，正确选项已经提供了明确的解题思路和答案，降低了部分难度。因此，该题目在选择题型内属于中等难度，对应等级3。", "convertible": true, "correct_option": "cosθ = (γ_{sv} - γ_{sl}) / γ_{lv} = -0.837, θ = 146.8° > 90°, cannot wet. To silver plate ceramic components, the surface of the ceramic must first be ground and polished to improve the wettability between the ceramic and the silver layer.", "choice_question": "Silver plating is required on alumina ceramic parts. It is known that at 1000°C, γ_{Al2O3(s)} = 1.00 mN/m, γ_{Ag(L)} = 0.92 mN/m, and γ_{Ag(L)-Al2O3(s)} = 1.77 mN/m. Can liquid silver wet the surface of alumina ceramic parts? What methods can be used to improve the wettability between them?", "conversion_reason": "The answer is a specific and standard explanation involving calculations and methods, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because the contact angle θ = 146.8° > 90° indicates non-wetting. Surface roughening can improve wettability by increasing effective surface area.", "B": "Yes, because γ_{Ag(L)} < γ_{Al2O3(s)}, satisfying the thermodynamic condition for wetting. Adding flux can further enhance wettability.", "C": "No, because γ_{Ag(L)-Al2O3(s)} > γ_{Al2O3(s)}. Pre-depositing a thin nickel layer can promote silver wetting through interfacial alloying.", "D": "Yes, because the spreading coefficient S = γ_{sv} - γ_{sl} - γ_{lv} is positive. Oxygen plasma treatment can reduce the contact angle." }, "correct_answer": "A", "explanation": "The correct answer is A because Young's equation gives cosθ = (1.00 - 1.77)/0.92 = -0.837, corresponding to θ = 146.8° > 90°, proving non-wetting. Surface roughening is a valid method to improve wettability. Option B is wrong because γ_{liquid} < γ_{solid} alone doesn't guarantee wetting when γ_{sl} is too high. Option C's nickel layer suggestion is plausible but doesn't change the immediate wetting calculation. Option D incorrectly calculates the spreading coefficient as positive when it's actually negative (-1.69 mN/m).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3106, "question": "Below the critical temperature Tc, superconductors possess complete (1) what property?", "answer": "Electrical conductivity", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字回答超导体在临界温度Tc以下具有的特定性质，答案是一个专业术语而非选项或判断，也不需要计算过程 | 知识层次: 题目考查超导体在临界温度以下的基本性质（完全导电性），属于基础概念的记忆和理解范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对超导体基本特性的记忆，属于最基础的定义简答级别。题目直接询问超导体在临界温度以下具有的特定性质（完全导电性），无需任何解释或分析过程，只需识别并选择正确术语即可。", "convertible": true, "correct_option": "Electrical conductivity", "choice_question": "Below the critical temperature Tc, superconductors possess complete which property?", "conversion_reason": "The answer is a standard term (Electrical conductivity) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Electrical conductivity", "B": "Magnetic susceptibility", "C": "Thermal conductivity", "D": "Mechanical ductility" }, "correct_answer": "A", "explanation": "The correct answer is A because superconductors below Tc exhibit zero electrical resistance (perfect conductivity). B is a trap for those confusing Meissner effect with bulk susceptibility. C exploits the common misconception that perfect electrical conductivity implies perfect thermal conductivity (violating Wiedemann-Franz law). D targets those associating 'perfect' properties with mechanical behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4478, "question": "Compute repeat unit molecular weight for polycarbonate", "answer": "254.27g/mol", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行具体的数值计算（计算聚碳酸酯的重复单元分子量），答案是一个具体的数值（254.27g/mol），这符合计算题的特征。 | 知识层次: 题目要求计算聚碳酸酯的重复单元分子量，这属于基本公式应用和简单计算，直接套用分子量计算公式即可完成，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用已知的重复单元分子量计算公式，属于单一公式直接计算类型。题目提供正确选项，学生只需识别并选择正确数值，无需进行复杂推导或多步骤计算，因此属于最低难度等级。", "convertible": true, "correct_option": "254.27g/mol", "choice_question": "Compute repeat unit molecular weight for polycarbonate:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "254.27 g/mol", "B": "228.29 g/mol", "C": "286.33 g/mol", "D": "198.22 g/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (254.27 g/mol) which is the molecular weight of the polycarbonate repeat unit (bisphenol A carbonate). Option B (228.29 g/mol) is a cognitive bias trap that subtracts the mass of one oxygen atom, exploiting the common mistake of overlooking the carbonate linkage. Option C (286.33 g/mol) is a professional intuition trap that adds the mass of an extra phenyl group, playing on the tendency to overcomplicate aromatic polymer structures. Option D (198.22 g/mol) is a multi-level verification trap that uses the molecular weight of just the bisphenol A unit without the carbonate group, targeting failure to consider the complete repeat unit structure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4003, "question": "Does the presence of a sharp notch favor brittle fracture in polymers?", "answer": "Yes, the presence of a sharp notch favors brittle fracture in polymers.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（对错），答案直接给出了明确的判断（Yes），符合判断题的特征 | 知识层次: 题目考查对聚合物断裂行为的基本概念记忆和理解，涉及尖锐缺口对脆性断裂的影响这一基本原理。 | 难度: 该题目属于选择题型中的概念理解对错判断难度。题目考察的是对聚合物断裂行为基本原理的理解，特别是缺口效应这一具体概念。虽然需要理解\"尖锐缺口促进脆性断裂\"这一原理，但不需要进行多概念比较或复杂分析，属于单一概念的应用判断。在选择题型中，这比纯粹的定义记忆（等级1）稍难，但比需要综合多个概念的复杂判断（等级3）简单。", "convertible": true, "correct_option": "Yes, the presence of a sharp notch favors brittle fracture in polymers.", "choice_question": "Does the presence of a sharp notch favor brittle fracture in polymers?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All polymers will exhibit brittle fracture when subjected to impact loading at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because not all polymers exhibit brittle fracture under impact loading at room temperature. The fracture behavior depends on multiple factors including polymer type, molecular weight, crystallinity, and testing conditions. For example, some toughened polymers or elastomers can exhibit ductile behavior even under impact loading. The use of 'all' makes this an absolute statement that doesn't account for material variations and exceptions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 888, "question": "Given that the nearest neighbor atomic spacing in a diamond unit cell is 0.1544nm, calculate the packing density ξ of diamond.", "answer": "The diamond unit cell contains 8 atoms (each of the 8 corner atoms contributes 1/8, each of the 6 face-centered atoms contributes 1/2, and each of the 4 internal atoms contributes 1). The atomic radius r = d/2 = 0.0772nm. The packing density ξ = (total volume of atoms)/(volume of unit cell) = [(8 × (4/3)πr³)]/a³ = [8 × (4/3) × 3.1416 × (0.0772nm)³]/(0.3566nm)³ ≈ 0.34.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解金刚石的堆积密度，答案中包含了具体的计算步骤和数值结果。 | 知识层次: 题目需要进行多步计算，包括原子半径的计算、单位晶胞体积的计算以及堆积密度的计算。此外，还需要理解金刚石晶胞中原子的分布和贡献比例，涉及多个概念的关联和综合分析。虽然不涉及复杂的推理或机理解释，但计算过程较为复杂，超出了简单应用的范畴。 | 难度: 在选择题中属于中等偏上难度，需要理解钻石晶胞的原子分布、计算原子半径、计算原子总体积和晶胞体积，并进行多步计算和综合分析。虽然题目提供了部分关键数据，但解题过程涉及多个概念和计算步骤，对学生的知识掌握和计算能力要求较高。", "convertible": true, "correct_option": "0.34", "choice_question": "Given that the nearest neighbor atomic spacing in a diamond unit cell is 0.1544nm, what is the packing density ξ of diamond?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.34", "B": "0.52", "C": "0.68", "D": "0.74" }, "correct_answer": "A", "explanation": "The correct packing density of diamond is 0.34 due to its open tetrahedral structure. Option B (0.52) mimics the FCC packing density, exploiting confusion between crystal structures. Option C (0.68) is a common error from incorrectly assuming hexagonal close packing. Option D (0.74) represents perfect HCP/FCC packing, a tempting but incorrect assumption for diamond's unique structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 438, "question": "The reason why the carbon solubility of austenite is higher than that of ferrite is because the crystal interstices of austenite are larger.", "answer": "(√)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性（√），符合判断题的特征 | 知识层次: 题目考查对奥氏体和铁素体晶体间隙大小及其对碳溶解度影响的基本概念记忆和理解，属于基础概念层面的知识。 | 难度: 该题目属于基础概念正误判断题，仅需记忆奥氏体和铁素体的碳溶解度差异原因这一基本原理即可作答，无需复杂分析或推理过程。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "(√)", "choice_question": "The reason why the carbon solubility of austenite is higher than that of ferrite is because the crystal interstices of austenite are larger.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit higher hardness than metallic materials at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are harder than metals, there are exceptions. Some metallic materials like hardened tool steels can exhibit hardness comparable to certain ceramics. The absolute term 'all' makes this statement false. This tests understanding of material property ranges and the danger of absolute statements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2676, "question": "According to the hard sphere model of crystals, if the diameter of the spheres remains unchanged, calculate the volume expansion when Fe transforms from fcc to bcc.", "answer": "a_fcc = 4 / sqrt(2) * r ⇒ V_fcc = a_fcc^3 = 64 / (2 * sqrt(2)) * r^3；a_bcc = 4 / sqrt(3) * r ⇒ V_bcc = a_bcc^3 = 64 / (3 * sqrt(3)) * r^3；ΔV = (1/2 * 64 / (3 * sqrt(3)) * r^3 - 1/4 * 64 / (2 * sqrt(2)) * r^3) / (1/4 * 64 / (2 * sqrt(2)) * r^3) = 9%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程中涉及晶体结构参数的计算和体积变化的推导，最终得出具体的百分比结果。 | 知识层次: 题目需要应用硬球模型和晶体结构的知识，进行多步计算（包括晶格常数计算、体积计算和体积变化百分比计算），并理解fcc和bcc结构的几何关系。虽然不涉及复杂的机理分析或创新设计，但需要综合运用多个概念和公式进行计算。 | 难度: 在选择题中属于中等偏上难度，需要理解fcc和bcc的晶体结构模型，掌握晶格常数与原子半径的关系，并进行多步计算和综合分析。虽然题目提供了正确选项的计算过程，但考生仍需具备较强的空间想象能力和数学计算能力才能正确理解和应用这些公式。", "convertible": true, "correct_option": "9%", "choice_question": "According to the hard sphere model of crystals, if the diameter of the spheres remains unchanged, the volume expansion when Fe transforms from fcc to bcc is:", "conversion_reason": "The calculation yields a specific numerical answer (9%), which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "9%", "B": "12%", "C": "6%", "D": "3%" }, "correct_answer": "A", "explanation": "The correct answer is 9% because in the hard sphere model, the packing fraction changes from 0.74 (fcc) to 0.68 (bcc), resulting in a volume expansion of approximately 9%. Option B (12%) is designed to exploit the common mistake of overestimating the packing efficiency difference. Option C (6%) targets those who might incorrectly average the packing fractions. Option D (3%) is a subtle trap for those who might confuse this with thermal expansion values in iron.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4816, "question": "Steady-state creep data taken for an iron at a stress level of 140 MPa(20,000 psi) are given here:\n\\begin{tabular}{cc}\n\\hline\\dot{\\epsilon}_{s}\\left(h^{-1}\\right) & T(K) \\\\\n\\hline 6.6 × 10^{-4} & 1090 \\\\\n8.8 × 10^{-2} & 1200 \\\\\n\\hline\n\\end{tabular}\nIf it is known that the value of the stress exponent n for this alloy is 8.5 , compute the steady-state creep rate at 1300 K and a stress level of 83 MPa(12,000 psi).", "answer": "the steady-state creep rate at 1300k and a stress level of 83 MPa is 4.31 × 10^{-2}h^{-1}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的数据和公式（应力指数n）计算稳态蠕变速率，答案是一个具体的数值计算结果，符合计算题的特征。 | 知识层次: 题目需要应用稳态蠕变速率公式，进行多步计算，包括温度转换、应力指数应用和数值计算，涉及概念关联和综合分析，但不需要复杂的推理分析或机理解释。 | 难度: 在选择题中属于中等难度，需要理解稳态蠕变速率与应力和温度的关系，并应用应力指数进行多步计算。题目涉及多个概念的综合运用和较为复杂的计算过程，但正确选项的提供降低了部分难度。", "convertible": true, "correct_option": "4.31 × 10^{-2}h^{-1}", "choice_question": "Given the steady-state creep data for an iron at a stress level of 140 MPa (20,000 psi) and knowing that the stress exponent n for this alloy is 8.5, what is the steady-state creep rate at 1300 K and a stress level of 83 MPa (12,000 psi)?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.31 × 10^{-2}h^{-1}", "B": "2.15 × 10^{-2}h^{-1}", "C": "8.62 × 10^{-2}h^{-1}", "D": "1.72 × 10^{-1}h^{-1}" }, "correct_answer": "A", "explanation": "正确答案A是通过精确应用Norton's creep law计算得出：首先用给定数据求出Qc，然后代入新条件计算。干扰项B设计为正确值的一半，利用AI可能忽略应力指数n的指数效应；干扰项C是正确值的两倍，针对可能错误线性外推的AI；干扰项D是正确值的四倍，针对可能混淆应力指数与温度依赖关系的AI。所有干扰项都保持合理的数量级，增加判断难度。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 111, "question": "For MgO, Al2O3, and Cr2O3, the cation-anion radius ratios are 0.47, 0.36, and 0.40 respectively. Is the solid solubility in the MgO-Cr2O3 system expected to be limited or unlimited? Why?", "answer": "The solid solubility between MgO and Cr2O3 is limited. Reason: different structure types, MgO has a NaCl-type structure while Cr2O3 has a corundum structure. Although (0.47-0.40)/0.47=14.89%<15%, continuous solid solution still cannot be formed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么MgO-Cr2O3系统的固溶度是有限的，需要文字解释和论述，而不是简单的选择、判断或计算。答案中提供了详细的解释和结构差异的分析。 | 知识层次: 题目需要理解并应用离子半径比与晶体结构类型的关系，分析不同氧化物之间的固溶度限制。虽然涉及基本概念（离子半径比、晶体结构类型），但需要综合分析两者之间的关联，并解释为什么即使离子半径比差异小于15%仍不能形成连续固溶体。这属于中等应用层次，需要多步分析和概念关联。 | 难度: 在选择题型中，该题目属于较高难度。题目不仅要求考生掌握离子半径比与固溶体形成条件的基本概念，还需要考生能够综合分析不同晶体结构类型对固溶度的影响。解题步骤涉及多个知识点的关联应用（包括半径比计算、结构类型判断、固溶度限制条件等），并需要考生在选择题的有限选项中准确判断出关键限制因素（结构类型差异）。虽然题目给出了具体数值，但需要考生理解15%规则的适用条件及其例外情况（结构类型不同时不能形成连续固溶体），这超出了单纯记忆性知识的范畴，属于中等应用层次的多角度分析。", "convertible": true, "correct_option": "The solid solubility between MgO and Cr2O3 is limited. Reason: different structure types, MgO has a NaCl-type structure while Cr2O3 has a corundum structure. Although (0.47-0.40)/0.47=14.89%<15%, continuous solid solution still cannot be formed.", "choice_question": "For MgO, Al2O3, and Cr2O3, the cation-anion radius ratios are 0.47, 0.36, and 0.40 respectively. Is the solid solubility in the MgO-Cr2O3 system expected to be limited or unlimited? Why?", "conversion_reason": "The answer is a standard explanation that can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Limited solubility due to different crystal structures despite radius ratio similarity", "B": "Unlimited solubility because the radius ratio difference (14.89%) is below 15% threshold", "C": "Limited solubility due to significant charge difference between Mg2+ and Cr3+", "D": "Unlimited solubility because both oxides have oxygen as the anion" }, "correct_answer": "A", "explanation": { "correct": "A is correct because while the radius ratio difference is below 15%, the fundamental crystal structure mismatch (NaCl-type vs corundum) prevents continuous solid solution formation.", "distractors": { "B": "This traps models that over-rely on the radius ratio rule without considering structural compatibility.", "C": "While charge difference is real, it's not the primary limiting factor here - this exploits models' tendency to prioritize electrostatic considerations.", "D": "This exploits surface-level similarity recognition (both being oxides) while ignoring critical structural differences." } }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4911, "question": "For copper, the heat capacity at constant volume C_V at 20 K is 0.38 J/mol-K and the Debye temperature is 340 K. Estimate the specific heat at 40 K.", "answer": "the specific heat for copper at 40 K is 47.8 J/kg-K.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计铜在40 K时的比热容，答案是一个具体的数值结果。 | 知识层次: 题目需要应用德拜模型和热容公式进行多步计算，涉及概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解德拜温度与热容的关系，并应用德拜模型进行多步计算。题目涉及概念关联和综合分析，但计算过程相对明确，属于综合性计算问题。", "convertible": true, "correct_option": "47.8 J/kg-K", "choice_question": "For copper, the heat capacity at constant volume C_V at 20 K is 0.38 J/mol-K and the Debye temperature is 340 K. Estimate the specific heat at 40 K.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "47.8 J/kg-K", "B": "0.76 J/mol-K", "C": "23.9 J/kg-K", "D": "1.14 J/mol-K" }, "correct_answer": "A", "explanation": "正确答案A是通过德拜模型计算得到的正确比热值。干扰项B直接线性外推了摩尔热容（0.38×2），忽略了低温区热容与T^3的非线性关系。干扰项C是正确答案的一半，利用了简单数值关系误导。干扰项D错误地采用了线性外推并叠加了30%增量，模拟了常见但错误的直觉修正。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 898, "question": "Term explanation: Slip system", "answer": "In a crystal, the combination of a slip plane and a slip direction on that plane is called a slip system.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对术语\"Slip system\"进行解释，需要文字解释和论述，符合简答题的特征 | 知识层次: 题目考查对\"Slip system\"这一基本概念的定义记忆和理解，属于材料科学中晶体变形的基础知识，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"slip system\"的基本定义，属于最基础的概念记忆层次。题目仅涉及单一概念的定义，不需要进行比较分析或复杂推理，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "In a crystal, the combination of a slip plane and a slip direction on that plane is called a slip system.", "choice_question": "Which of the following correctly defines a slip system?", "conversion_reason": "The original question is a term explanation (short answer) with a clear and concise definition as the answer. It can be converted into a multiple-choice question by presenting the correct definition among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In a crystal, the combination of a slip plane and a slip direction on that plane is called a slip system", "B": "The system of dislocations that enables plastic deformation in polycrystalline materials", "C": "The crystallographic plane with the highest atomic density where slip preferentially occurs", "D": "A mathematical model describing the relationship between shear stress and dislocation motion" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a slip system as the combination of a slip plane and slip direction. Option B is incorrect because it describes dislocation networks rather than a specific slip system. Option C is a partial definition that only mentions the slip plane but omits the slip direction, exploiting the common oversight of neglecting the directional component. Option D describes the Peierls-Nabarro model for dislocation motion, which is related but distinct from the definition of a slip system.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1554, "question": "6. Eutectic transformation", "answer": "The transformation in a binary alloy where a single liquid phase simultaneously transforms into two different solid phases at a constant temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对术语进行文字解释和论述，答案形式为一段描述性文字，没有选项或计算要求 | 知识层次: 题目考查对共晶转变这一基本概念的记忆和理解，属于定义性知识 | 难度: 在选择题型中，该题目属于概念解释和描述难度。虽然涉及基础概念记忆，但需要考生准确理解并描述共晶转变的定义和特征，包括从单一液相同时转变为两种不同固相的过程以及恒温条件。这比简单记忆定义（等级1）要求更高，但不需要复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "The transformation in a binary alloy where a single liquid phase simultaneously transforms into two different solid phases at a constant temperature.", "choice_question": "Which of the following best describes eutectic transformation?", "conversion_reason": "The answer is a standard definition of a concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The transformation in a binary alloy where a single liquid phase simultaneously transforms into two different solid phases at a constant temperature", "B": "The process where a solid solution decomposes into two distinct phases upon cooling below the solubility limit", "C": "A diffusionless transformation where a parent phase changes crystal structure without composition change", "D": "The precipitation of a second phase from a supersaturated solid solution at elevated temperatures" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines eutectic transformation as the simultaneous formation of two solid phases from a single liquid at a fixed temperature. Option B describes spinodal decomposition, which is a different phase separation mechanism. Option C characterizes martensitic transformation, a diffusionless process unrelated to eutectic reactions. Option D depicts precipitation hardening, a strengthening mechanism distinct from eutectic solidification. These distractors exploit common material science concept confusions by presenting similar but fundamentally different phase transformation mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 60, "question": "What type of silicate structure does Mg3[Si4O10](OH)2 belong to?", "answer": "Layered (double-chain)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释Mg3[Si4O10](OH)2所属的硅酸盐结构类型，需要文字描述和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目考查对硅酸盐结构分类的基本概念记忆和理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（硅酸盐结构分类），但需要考生准确记忆并区分不同类型的硅酸盐结构（如层状、双链等）。相比等级1的直接定义简答，该题目要求考生对硅酸盐结构分类有更深入的理解和记忆，属于概念解释和描述层次的难度。", "convertible": true, "correct_option": "Layered (double-chain)", "choice_question": "What type of silicate structure does Mg3[Si4O10](OH)2 belong to?", "conversion_reason": "The answer is a standard term in geology/silicate chemistry, making it suitable for conversion to a multiple-choice format where 'Layered (double-chain)' would be the correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Single-chain (pyroxene)", "B": "Double-chain (amphibole)", "C": "Layered (phyllosilicate)", "D": "Framework (tectosilicate)" }, "correct_answer": "C", "explanation": "The correct answer is C (Layered) because Mg3[Si4O10](OH)2 is the formula for talc, a classic phyllosilicate with a sheet structure. The [Si4O10] unit indicates a 2D infinite sheet of tetrahedra. Option A exploits the cognitive bias of seeing 'Mg' and assuming pyroxene structure. Option B is a professional intuition trap - the formula resembles amphibole but lacks the characteristic double-chain [Si4O11] unit. Option D is a verification trap - the Si:O ratio seems close to framework silicates but ignores the (OH) groups characteristic of layered structures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 312, "question": "What is a crystal face family?", "answer": "A crystal face family refers to the combination of crystal faces with the same arrangement of atoms or molecules in a crystal. Due to symmetry relationships, there are often more than one type of such faces.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"crystal face family\"进行文字解释和论述，答案提供了概念的定义和特征描述，符合简答题的特点。 | 知识层次: 题目考查晶体面族的基本定义和对称性关系的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但要求考生不仅记住定义，还需要理解晶体面族的概念及其背后的对称性关系。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "A crystal face family refers to the combination of crystal faces with the same arrangement of atoms or molecules in a crystal. Due to symmetry relationships, there are often more than one type of such faces.", "choice_question": "Which of the following best defines a crystal face family?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct definition as one of the options and other plausible but incorrect definitions as distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A set of crystallographic planes related by symmetry operations, sharing the same atomic arrangement but differing in orientation", "B": "All external surfaces of a crystal that grow at the same rate during solidification", "C": "The dominant crystallographic plane that determines the overall crystal morphology", "D": "A group of crystal faces that exhibit identical surface energy under all thermodynamic conditions" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines a crystal face family as symmetry-related planes with identical atomic arrangements. Option B exploits the common misconception about growth rates determining face families. Option C triggers the cognitive bias of seeking a 'dominant' feature. Option D presents a thermodynamic trap by suggesting unconditional surface energy equivalence, which is only true for perfect symmetry conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2131, "question": "The jump frequency of carbon atoms in solid solution is Γ=1.7×10^28 s^-1 at 925℃ and Γ=2.1×10^9 s^-1 at 20℃. Discuss the effect of temperature on the diffusion coefficient. The interstitial diffusion calculation formula is D=α²PΓ, where α is the distance between adjacent parallel crystal planes, P is the jump probability in a given direction, and Γ is the atomic jump frequency.", "answer": "D_925℃/D_20℃=8.1×10^17", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和数据进行数值计算，最终得出一个具体的数值结果（D_925℃/D_20℃=8.1×10^17），这符合计算题的特征。 | 知识层次: 题目需要应用给定的扩散系数公式进行多步计算，并理解温度对扩散系数的影响机制。虽然计算本身不复杂，但需要关联温度与跳频的关系，并进行综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散系数与温度的关系公式，并进行两步计算（首先理解公式D=α²PΓ的含义，然后代入不同温度下的Γ值计算比例）。虽然计算本身不复杂，但需要正确关联概念和公式，属于综合性计算问题。", "convertible": true, "correct_option": "D_925℃/D_20℃=8.1×10^17", "choice_question": "The jump frequency of carbon atoms in solid solution is Γ=1.7×10^28 s^-1 at 925℃ and Γ=2.1×10^9 s^-1 at 20℃. Using the interstitial diffusion calculation formula D=α²PΓ, what is the ratio of the diffusion coefficients D_925℃/D_20℃?", "conversion_reason": "The question can be converted into a multiple-choice format because it has a specific numerical answer. The original question is a calculation problem with a definitive solution, making it suitable for conversion.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.1×10^17", "B": "1.7×10^28/2.1×10^9 = 8.1×10^18", "C": "ln(1.7×10^28/2.1×10^9) = 43.8", "D": "(1.7×10^28 - 2.1×10^9) = 1.7×10^28" }, "correct_answer": "A", "explanation": "The correct answer is A because the ratio of diffusion coefficients is directly calculated by the ratio of jump frequencies (Γ_925℃/Γ_20℃). Option B incorrectly assumes the ratio needs an extra factor of 10. Option C mistakenly applies a logarithmic transformation. Option D erroneously subtracts the frequencies instead of taking their ratio.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 729, "question": "During the cooling process of the melt, the greater the degree of undercooling, the greater the overall crystallization rate", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对结晶速率与过冷度关系这一基本概念的记忆和理解，属于材料科学中的基础知识点。 | 难度: 在选择题型中，此题属于基本概念正误判断，仅需记忆并确认\"过冷度与结晶速率的关系\"这一基础概念的正确性，无需深入理解或分析多个概念，解题步骤简单直接。", "convertible": true, "correct_option": "√", "choice_question": "During the cooling process of the melt, the greater the degree of undercooling, the greater the overall crystallization rate", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All metallic glasses exhibit a distinct glass transition temperature (Tg) when heated.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most metallic glasses do show a glass transition temperature, some compositions with extremely high glass-forming ability may crystallize before reaching Tg. The statement uses 'all' which is too absolute. Additionally, the detection of Tg depends on the sensitivity of measurement techniques, creating a concept boundary issue.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2876, "question": "For an Fe-3%Si alloy containing MnS particles with a radius of 0.05μm and a volume fraction of 0.01, during the annealing process below 850°C, when the average grain diameter of the matrix reaches 6μm, normal grain growth stops. Analyze the reason for this phenomenon.", "answer": "For silicon steel sheets containing MnS particles with a radius of 0.05μm and a volume fraction of 0.01 during recrystallization, the limiting grain diameter is calculated as: D_lim = (4r)/(3φ) = (4/3) × (0.05/0.01) = 6.67μm. It is precisely due to the presence of these dispersed particles that when the silicon steel sheet is annealed below 850°C, normal grain growth stops once the average grain diameter of the matrix reaches 6μm.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析现象的原因，答案提供了详细的文字解释和论述，涉及材料科学中的晶粒生长机制和分散颗粒的影响，属于需要深入分析和解释的简答题类型。 | 知识层次: 题目要求分析Fe-3%Si合金在退火过程中晶粒生长停止的现象，涉及分散相粒子对晶粒生长的抑制作用。需要理解Zener钉扎效应的原理，并运用公式计算极限晶粒尺寸，同时结合材料的具体参数进行综合分析。这需要较高的推理分析和机理解释能力，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "It is precisely due to the presence of these dispersed particles that when the silicon steel sheet is annealed below 850°C, normal grain growth stops once the average grain diameter of the matrix reaches 6μm.", "choice_question": "For an Fe-3%Si alloy containing MnS particles with a radius of 0.05μm and a volume fraction of 0.01, during the annealing process below 850°C, when the average grain diameter of the matrix reaches 6μm, normal grain growth stops. What is the reason for this phenomenon?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the reason behind the phenomenon.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The MnS particles exert a Zener pinning force that balances the driving force for grain growth when the grain size reaches 6μm", "B": "The solubility limit of MnS in the Fe-3%Si matrix is reached at 6μm grain size, causing precipitation saturation", "C": "The critical grain boundary curvature for migration is achieved at 6μm, satisfying the thermodynamic equilibrium condition", "D": "The stored strain energy from cold working is fully released when grains reach 6μm, eliminating the driving force for growth" }, "correct_answer": "A", "explanation": "The correct answer is A because Zener pinning theory explains how second-phase particles can inhibit grain growth by exerting a pinning force proportional to particle volume fraction and inversely proportional to particle radius. Option B exploits solubility confusion (MnS is insoluble in Fe-Si). Option C misapplies curvature concepts (equilibrium requires zero curvature). Option D uses a plausible-sounding but irrelevant strain energy argument (annealing already removed strain).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 107, "question": "Explain the similarities between solid solutions, lattice defects, and non-stoichiometric compounds", "answer": "Solid solutions, lattice defects, and non-stoichiometric compounds are all point defects, which are crystal structure defects, and they are single-phase homogeneous solids with structures identical to the host crystal phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释固体溶液、晶格缺陷和非化学计量化合物之间的相似性，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对固体溶液、晶格缺陷和非化学计量化合物这些基本概念的记忆和理解，以及它们之间的相似性。这些都属于晶体结构缺陷的基础知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目要求考生理解并描述三个相关概念（固溶体、晶格缺陷和非化学计量化合物）的相似性。虽然需要掌握多个概念，但题目仅要求识别和描述它们的共同特征（点缺陷、晶体结构缺陷、单相均质固体），而不需要进行复杂的比较分析或推导。这属于概念解释和描述的难度层次。", "convertible": true, "correct_option": "Solid solutions, lattice defects, and non-stoichiometric compounds are all point defects, which are crystal structure defects, and they are single-phase homogeneous solids with structures identical to the host crystal phase.", "choice_question": "Which of the following best describes the similarities between solid solutions, lattice defects, and non-stoichiometric compounds?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "They are all point defects with structures identical to the host crystal phase", "B": "They all involve substitutional atoms replacing host atoms in the lattice", "C": "They all result in significant changes to the crystal's unit cell parameters", "D": "They all require the presence of interstitial atoms to maintain charge neutrality" }, "correct_answer": "A", "explanation": "Correct answer A identifies the fundamental similarity that these are all point defects maintaining the host crystal structure. Option B is incorrect because non-stoichiometric compounds don't necessarily involve substitutional atoms. Option C is a cognitive bias trap - while these defects may slightly alter parameters, not 'significantly'. Option D is a professional intuition trap - interstitial atoms are not required for all these cases, especially solid solutions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 436, "question": "The eutectic transformation occurs in systems where the liquid phase is completely miscible and the solid phase is completely immiscible.", "answer": "(×)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述，要求判断其正确与否（答案给出的是×表示错误），符合判断题的特征。 | 知识层次: 题目考查共晶转变的基本概念，属于定义和基本原理的记忆性知识 | 难度: 该题目属于基础概念正误判断，仅需记忆共晶转变的定义和条件即可作答，无需深入理解或分析多个概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "(×)", "choice_question": "The eutectic transformation occurs in systems where the liquid phase is completely miscible and the solid phase is completely immiscible.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect ionic bonding with no covalent character.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics have predominantly ionic bonding, most exhibit some degree of covalent character. The statement is incorrect because it uses the absolute term 'all' and ignores the spectrum of bonding behavior in ceramics. Materials like silicon carbide (SiC) and silicon nitride (Si3N4) have significant covalent bonding.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2335, "question": "Given that the recrystallization activation energy of a Cu-Zn alloy (w_Zn=0.30) is 250 kJ/mol, and this alloy takes 1 hour to complete recrystallization at a constant temperature of 400°C, how many hours does it take for this alloy to complete recrystallization at a constant temperature of 390°C? (Shanghai Jiao Tong University postgraduate entrance exam question)", "answer": "Given T_1=400°C=673 K, t_1=1 h, T_2=390°C=663 K, Q=2.5×10^5 J/mol. Let the time required to complete recrystallization at 390°C be t_2, then from A e^(-Q/(R T_1 )) t_1=A e^(-Q/(R T_2 )) t_2, we get t_1/t_2=e^[-Q/R (1/T_2 -1/T_1 )]=e^[-2.5×10^5/8.31×(1/663-1/673)]=0.509. Therefore, t_2=1.96 h.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解在390°C下完成再结晶所需的时间，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目涉及多步计算和公式应用，需要理解再结晶激活能的概念，并能够正确应用阿伦尼乌斯公式进行计算。虽然计算过程较为直接，但需要将温度转换为开尔文温标，并进行指数运算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解并应用阿伦尼乌斯方程进行多步计算，涉及温度转换、指数运算和综合分析。虽然题目提供了所有必要参数，但解题过程需要较强的概念关联能力和计算技巧，属于综合性计算问题。", "convertible": true, "correct_option": "1.96 h", "choice_question": "Given that the recrystallization activation energy of a Cu-Zn alloy (w_Zn=0.30) is 250 kJ/mol, and this alloy takes 1 hour to complete recrystallization at a constant temperature of 400°C, how many hours does it take for this alloy to complete recrystallization at a constant temperature of 390°C?", "conversion_reason": "The calculation yields a specific numerical answer (1.96 h), which can be presented as one of the options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.96 h", "B": "0.51 h", "C": "3.82 h", "D": "1.00 h" }, "correct_answer": "A", "explanation": "The correct answer is A (1.96 h) calculated using the Arrhenius equation for recrystallization kinetics. Option B (0.51 h) exploits the cognitive bias of expecting faster recrystallization at lower temperatures by incorrectly inverting the temperature difference. Option C (3.82 h) is designed to trap those who miscalculate the exponential term by using 390/400 instead of the correct temperature conversion to Kelvin. Option D (1.00 h) preys on the intuition that small temperature changes might have negligible effects, ignoring the exponential nature of the Arrhenius relationship.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 755, "question": "After water interacts with clay, what can be found around the clay colloidal particles as the distance increases: (9) what?", "answer": "Loosely bound water", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述\"what can be found around the clay colloidal particles as the distance increases\"，答案\"Loosely bound water\"是一个简短的文字描述，符合简答题的特征。 | 知识层次: 题目考查的是对粘土胶体颗粒周围水分子分布的基础概念记忆，属于材料科学中关于粘土-水相互作用的基本原理知识，仅需记忆和理解即可回答。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即黏土胶体颗粒周围随着距离增加会出现什么（松散结合水）。题目不涉及概念解释或复杂体系分析，仅需回忆基本定义即可作答，属于最基础的选择题难度等级。", "convertible": true, "correct_option": "Loosely bound water", "choice_question": "After water interacts with clay, what can be found around the clay colloidal particles as the distance increases?", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Loosely bound water", "B": "Hydrated cations in Stern layer", "C": "Electric double layer with fixed charge density", "D": "Free water molecules with bulk properties" }, "correct_answer": "A", "explanation": "The correct answer is A because as distance increases from clay colloidal particles, the water molecules transition from tightly bound to loosely bound states. Option B is a cognitive bias trap - while hydrated cations exist, they're concentrated in the Stern layer near the surface. Option C exploits material science intuition by suggesting the entire double layer persists at all distances. Option D is a multi-level verification trap - while bulk water properties eventually appear, there's always an intermediate region of loosely bound water first.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 931, "question": "What is the method of nucleation during the recrystallization process?", "answer": "Recrystallization nucleation often occurs in existing regions of deformation inhomogeneity, such as near grain boundaries, shear bands, deformation bands, and around second-phase particles.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释再结晶过程中成核的方法，答案提供了详细的文字解释和论述，没有选项或计算要求。 | 知识层次: 题目涉及再结晶过程中成核的具体位置和机制，需要理解变形不均匀区域的概念，并将成核现象与材料微观结构特征（如晶界、剪切带、第二相粒子等）关联起来。这需要一定的综合分析能力和对材料变形与再结晶过程的理解，超出了单纯的基础概念记忆。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及再结晶过程中的成核方法，正确选项提到了变形不均匀区域的多个具体位置（晶界、剪切带、变形带、第二相粒子周围），这要求考生不仅知道再结晶成核的基本概念，还需要掌握成核发生的具体位置及其与变形不均匀性的关联。这种题目需要考生综合应用材料科学中的变形和再结晶知识，属于中等应用层次。", "convertible": true, "correct_option": "Recrystallization nucleation often occurs in existing regions of deformation inhomogeneity, such as near grain boundaries, shear bands, deformation bands, and around second-phase particles.", "choice_question": "Which of the following describes the method of nucleation during the recrystallization process?", "conversion_reason": "The answer is a standard description of the nucleation process during recrystallization, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization nucleation often occurs in existing regions of deformation inhomogeneity, such as near grain boundaries, shear bands, deformation bands, and around second-phase particles", "B": "Nucleation occurs uniformly throughout the material volume due to homogeneous strain energy distribution", "C": "Primary nucleation sites are determined by the lowest stacking fault energy regions in the crystal structure", "D": "Nucleation initiates exclusively at triple junctions where three grain boundaries meet" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual heterogeneous nucleation mechanism in recrystallization, where defects and inhomogeneities serve as preferential sites. Option B exploits the common misconception about homogeneous nucleation in solid-state transformations. Option C uses a plausible-sounding but incorrect criterion (stacking fault energy) that might mislead AI models familiar with dislocation theories. Option D creates an overly specific trap by exaggerating the importance of triple junctions while ignoring other nucleation sites.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3881, "question": "What is the tempering temperature range required to produce a quenched and tempered eutectoid steel with a HRC hardness of less than 50?", "answer": "Temper at a temperature higher than 330 degrees Celsius, but less than 727 degrees Celsius.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述特定温度范围，答案需要文字说明而非选择、判断或计算 | 知识层次: 题目需要理解回火温度与硬度之间的关系，并综合应用相图知识和硬度要求来确定温度范围，涉及多步分析和概念关联。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及淬火和回火工艺的知识，要求考生知道回火温度对硬度的影响，以及共析钢的回火温度范围。此外，还需要将HRC硬度与回火温度关联起来，综合分析得出正确答案。虽然不需要复杂的计算，但需要对材料热处理的基本原理有较好的掌握。", "convertible": true, "correct_option": "Temper at a temperature higher than 330 degrees Celsius, but less than 727 degrees Celsius.", "choice_question": "What is the tempering temperature range required to produce a quenched and tempered eutectoid steel with a HRC hardness of less than 50?", "conversion_reason": "The answer is a specific and standardized temperature range, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Temper at a temperature higher than 330°C, but less than 727°C", "B": "Temper at a temperature between 200°C and 400°C to avoid excessive softening", "C": "Temper at 727°C to achieve optimal hardness reduction while maintaining strength", "D": "Temper below 330°C to retain sufficient martensite hardness" }, "correct_answer": "A", "explanation": "Correct answer A reflects the actual tempering range for eutectoid steel where hardness drops below HRC 50. Option B exploits the common misconception that tempering must stay below 400°C for hardness control. Option C traps those who confuse the eutectoid temperature with proper tempering conditions. Option D targets the intuitive but incorrect belief that lower tempering preserves hardness better, ignoring the need for sufficient tempering to achieve the specified hardness.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3301, "question": "Compare the lattice shear during bainitic transformation, pearlitic transformation, and martensitic transformation", "answer": "Pearlitic transformation involves no lattice shear, while bainitic transformation and martensitic transformation involve lattice shear.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对不同相变过程中的晶格剪切进行比较和解释，答案以文字论述形式呈现，没有涉及计算或选择判断。 | 知识层次: 题目要求比较三种相变过程中的晶格剪切现象，涉及多个概念（bainitic、pearlitic、martensitic transformation）的关联和综合分析。虽然不涉及复杂计算，但需要对不同相变机制的理解和比较，属于中等应用层次。 | 难度: 在选择题型中，该题目要求考生对三种不同的相变过程（贝氏体相变、珠光体相变和马氏体相变）的晶格剪切行为进行比较分析。这需要考生不仅掌握每种相变的基本概念，还需要理解晶格剪切在不同相变中的具体表现及其差异。此外，题目涉及的知识点较为深入，需要考生能够将多个概念关联起来进行综合分析，属于多角度分析论述的层次。因此，在选择题型内，该题目的难度等级为4。", "convertible": true, "correct_option": "Pearlitic transformation involves no lattice shear, while bainitic transformation and martensitic transformation involve lattice shear.", "choice_question": "Compare the lattice shear during bainitic transformation, pearlitic transformation, and martensitic transformation. Which of the following statements is correct?", "conversion_reason": "The answer is a standard comparison that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit the multiple-choice format by asking for the correct statement among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pearlitic transformation involves no lattice shear, while bainitic transformation and martensitic transformation involve lattice shear", "B": "All three transformations involve lattice shear, with martensitic showing the highest shear strain", "C": "Only martensitic transformation involves lattice shear, while pearlitic and bainitic are diffusion-controlled with no shear", "D": "Bainitic transformation involves higher lattice shear than martensitic due to its intermediate transformation temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because pearlitic transformation is a diffusion-controlled process with no lattice shear, while both bainitic and martensitic transformations involve displacive mechanisms with lattice shear. Option B is incorrect because it falsely claims pearlitic transformation involves shear. Option C is a partial truth trap that incorrectly excludes bainitic transformation from shear mechanisms. Option D exploits the common misconception about temperature effects on shear magnitude, reversing the actual relationship between bainitic and martensitic transformations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2828, "question": "Determine the engineering strain εe and true strain εT when compressed from h to 0.9h, and explain which one better reflects the true deformation characteristics", "answer": "εe = (0.9 - 1)h / h = -10%; εT = ln(0.9h / h) = -10.5%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算工程应变和真实应变）并应用相关公式，答案也以数值形式给出，符合计算题的特征。 | 知识层次: 题目要求进行基本的工程应变和真实应变计算，涉及直接套用公式（εe = ΔL/L0 和 εT = ln(L/L0)），属于简单应用层次。虽然需要理解两种应变的定义，但计算过程直接且无需多步推理或综合分析。 | 难度: 在选择题中属于简单应用难度，需要应用工程应变和真实应变两个基本公式进行计算，但不需要复杂的推导或分析。题目直接给出了变形前后的高度比，只需套用公式即可得出结果。虽然涉及两个公式，但计算过程简单直接，属于选择题型中的基础难度水平。", "convertible": true, "correct_option": "εe = -10%; εT = -10.5%", "choice_question": "When compressed from h to 0.9h, the engineering strain εe and true strain εT are:", "conversion_reason": "The answer is a specific numerical result, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "εe = -10%; εT = -10.5%", "B": "εe = -10%; εT = -9.5%", "C": "εe = -11.1%; εT = -10.5%", "D": "εe = -9.1%; εT = -9.5%" }, "correct_answer": "A", "explanation": "正确答案A的计算过程：工程应变εe = (0.9h - h)/h = -10%；真实应变εT = ln(0.9h/h) = -10.5%。干扰项B利用了真实应变计算中常见的对数近似错误（认为ln(0.9)≈-0.095）。干扰项C故意混淆了压缩和拉伸情况下的应变符号。干扰项D结合了工程应变计算时的分母错误（用0.9h作分母）和对数近似错误。这些干扰项都利用了材料科学中应变计算时常见的认知偏差和直觉陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2479, "question": "What are the basic characteristics of the Bravais lattice?", "answer": "It has periodicity and symmetry, and each node is an equivalent point.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释Bravais lattice的基本特征，答案以文字论述形式给出，不需要计算或选择选项 | 知识层次: 题目考查对Bravais晶格基本特征的定义和记忆，属于基础概念的理解和复述，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆并识别Bravais晶格的基本特征（周期性和对称性），属于最基础的定义简答层次。不需要复杂的解释或比较分析，只需直接回忆相关定义即可选择正确答案。", "convertible": true, "correct_option": "It has periodicity and symmetry, and each node is an equivalent point.", "choice_question": "What are the basic characteristics of the Bravais lattice?", "conversion_reason": "The answer is a standard description of the Bravais lattice's characteristics, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It has periodicity and symmetry, and each node is an equivalent point", "B": "It has periodicity and symmetry, but nodes may represent different atomic species", "C": "It has perfect periodicity but no rotational symmetry requirements", "D": "It requires identical atomic arrangements at all nodes regardless of crystal system" }, "correct_answer": "A", "explanation": "The correct answer A captures the three essential characteristics of Bravais lattices: 1) strict periodicity, 2) inherent symmetry, and 3) mathematical equivalence of all lattice points. Option B is misleading because while real crystals may have different atoms, Bravais lattices are mathematical constructs where all nodes must be equivalent. Option C incorrectly removes the symmetry requirement, which is fundamental to Bravais classification. Option D introduces an overly restrictive atomic-level condition that doesn't apply to the abstract lattice concept.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 377, "question": "同质异构体", "answer": "Chemical compositions are the same but form different crystal structures due to different thermodynamic conditions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"同质异构体\"进行文字解释和论述，答案提供了概念的定义和形成原因，符合简答题的特征 | 知识层次: 题目考查同质异构体的基本定义和形成原因，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生理解并区分\"同质异构体\"的定义特征（相同化学成分但不同晶体结构）及其形成原因（不同热力学条件）。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Chemical compositions are the same but form different crystal structures due to different thermodynamic conditions.", "choice_question": "下列关于同质异构体的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chemical compositions are the same but form different crystal structures due to different thermodynamic conditions", "B": "Different chemical compositions that form identical crystal structures under the same processing conditions", "C": "Materials with identical crystal structures but different chemical compositions due to alloying effects", "D": "Materials that transform between different crystal structures without any change in temperature or pressure" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines polymorphs (allotropes) where composition remains constant but crystal structure changes with thermodynamic conditions. Option B reverses the key relationship between composition and structure. Option C describes isomorphous systems, not polymorphs. Option D describes impossible behavior violating thermodynamic laws. Advanced AIs may select B due to overgeneralizing structure-property relationships, or D by misapplying martensitic transformation concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3283, "question": "What is the significance of the TTT diagram for eutectoid carbon steel in practical heat treatment?", "answer": "The isothermal transformation C-curve (TTT curve) can determine the process parameters during isothermal heat treatment of steel, namely the isothermal temperature, isothermal time, and the microstructure after heat treatment.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释TTT图的实际意义，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释TTT图在实际热处理中的意义，涉及对等温热处理过程参数（温度、时间）和最终组织的综合分析，需要将理论知识与实际应用相结合，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解TTT图的基本概念及其在热处理中的应用，并能将多个概念（如等温温度、时间和显微组织）关联起来进行综合分析。虽然不涉及复杂的计算，但需要对材料科学中的基本原理有较好的掌握。", "convertible": true, "correct_option": "The isothermal transformation C-curve (TTT curve) can determine the process parameters during isothermal heat treatment of steel, namely the isothermal temperature, isothermal time, and the microstructure after heat treatment.", "choice_question": "What is the significance of the TTT diagram for eutectoid carbon steel in practical heat treatment?", "conversion_reason": "The answer is a standard explanation that can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Predicts the critical cooling rate required to avoid pearlite formation during continuous cooling", "B": "Determines the maximum hardness achievable through martensitic transformation at any temperature", "C": "Provides exact transformation times for bainite formation under non-isothermal conditions", "D": "Shows the equilibrium phases present at different carbon concentrations" }, "correct_answer": "A", "explanation": "The correct answer is A because TTT diagrams specifically show transformation kinetics under isothermal conditions, which can be used to infer critical cooling rates. B is incorrect because hardness depends on actual cooling conditions, not just temperature. C is wrong as TTT diagrams are for isothermal conditions only. D describes a phase diagram, not a TTT diagram.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4851, "question": "A parallel-plate capacitor using a dielectric material having an \\varepsilon_{\\mathrm{r}} of 2.2 has a plate spacing of 2mm ( 0.08 in.). If another material having a dielectric constant of 3.7 is used and the capacitance is to be unchanged, what must be the new spacing between the plates?", "answer": "the new spacing between the plates must be 3.36 mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解新的板间距，答案是一个具体的数值结果。 | 知识层次: 题目涉及基本的电容公式应用和简单的数值计算，只需要直接套用公式并调整参数即可得到答案，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目要求应用电容的基本公式（C = εA/d），并通过简单的代数运算（保持C不变，调整d以补偿ε的变化）来求解新的板间距。虽然涉及两个不同的介电常数，但解题步骤直接且无需复杂的推导或概念整合，属于选择题型中较为基础的难度水平。", "convertible": true, "correct_option": "3.36 mm", "choice_question": "A parallel-plate capacitor using a dielectric material having an ε_{\\mathrm{r}} of 2.2 has a plate spacing of 2mm ( 0.08 in.). If another material having a dielectric constant of 3.7 is used and the capacitance is to be unchanged, what must be the new spacing between the plates?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.36 mm", "B": "1.19 mm", "C": "2.00 mm", "D": "4.44 mm" }, "correct_answer": "A", "explanation": "正确答案A通过电容公式C=ε₀εᵣA/d推导得出，保持C不变时d应与εᵣ成正比变化。干扰项B是错误地认为d与εᵣ成反比的计算结果。干扰项C利用直觉认为间距不应改变，忽略了介电常数变化的影响。干扰项D是错误地将原始间距乘以介电常数比值的平方。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2538, "question": "What is Vegard's law?", "answer": "Experiments have found that when two isomorphous salts form a continuous solid solution, the lattice constant of the solid solution has a linear relationship with the composition, meaning the lattice constant is proportional to the concentration of any component. This is Vegard's law.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释Vegard's law的定义和内容，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查Vegard's law的基本定义和原理，属于基础概念的记忆和理解范畴，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。虽然题目涉及Vegard's law的定义，但正确选项提供了较为详细的解释，包括实验发现、线性关系和比例关系等关键要素，超出了简单定义的范围。然而，题目并未要求考生进行复杂的概念体系阐述或比较分析，因此属于中等难度。", "convertible": true, "correct_option": "Experiments have found that when two isomorphous salts form a continuous solid solution, the lattice constant of the solid solution has a linear relationship with the composition, meaning the lattice constant is proportional to the concentration of any component. This is Vegard's law.", "choice_question": "Which of the following correctly describes Vegard's law?", "conversion_reason": "The answer is a standard definition of Vegard's law, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Experiments have found that when two isomorphous salts form a continuous solid solution, the lattice constant of the solid solution has a linear relationship with the composition, meaning the lattice constant is proportional to the concentration of any component.", "B": "The elastic modulus of a composite material varies linearly with the volume fraction of its constituents, as observed in most metal-ceramic systems.", "C": "The thermal expansion coefficient of a solid solution alloy follows a quadratic relationship with composition, deviating significantly from linearity at high solute concentrations.", "D": "The electrical conductivity of doped semiconductors shows an exponential dependence on dopant concentration, as described by Vegard's original formulation." }, "correct_answer": "A", "explanation": "Option A is the correct definition of Vegard's law, which specifically deals with lattice constants in solid solutions. Option B incorrectly applies the linearity concept to elastic modulus, exploiting the AI's tendency to generalize material property relationships. Option C introduces a plausible-sounding nonlinear relationship for thermal expansion, targeting the AI's knowledge of non-ideal solution behavior. Option D combines semiconductor physics with Vegard's name, creating a convincing but entirely wrong association that could trap AI models familiar with both concepts separately.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 35, "question": "Lithium fluoride (LiF) has a NaCl-type structure, and its measured density is 2.6 g/cm³. Based on this data, calculate the unit cell parameter.", "answer": "Assuming the volume of the unit cell is V and the relative atomic mass is M, for the NaCl-type structure, n=4. Then the unit cell volume V = (n M)/(N0ρ) = (4×26)/(6.023×10²³×2.6) = 6.64×10⁻²³ cm³. Therefore, the unit cell parameter: a₀ = ³√V = 0.405 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求基于给定的密度和晶体结构类型，通过数值计算和公式应用（如单位晶胞体积公式）来求解晶胞参数。答案展示了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，需要根据给定的密度和晶体结构类型计算晶胞参数。虽然需要理解NaCl型结构的基本特征和单位晶胞中的原子数，但整体上是一个直接套用公式的计算过程，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要理解NaCl型结构的基本概念和密度计算公式，但解题步骤相对直接，仅需套用单一公式（V = (n M)/(N0ρ)）并进行简单计算即可得出结果。不需要多个公式组合或复杂的概念分析，因此在选择题型内属于较低难度。", "convertible": true, "correct_option": "0.405 nm", "choice_question": "Lithium fluoride (LiF) has a NaCl-type structure, and its measured density is 2.6 g/cm³. Based on this data, the unit cell parameter is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.405 nm", "B": "0.402 nm", "C": "0.408 nm", "D": "0.395 nm" }, "correct_answer": "A", "explanation": "正确答案A基于LiF的NaCl型结构计算得出，考虑了每个晶胞含有4个LiF分子，使用密度公式ρ=(Z×M)/(a³×N_A)反推晶格常数a。干扰项B利用了常见认知偏差，数值接近但错误地使用了LiF的弹性模量数据进行修正；干扰项C设计为基于第一印象的直觉判断，看似合理但忽略了温度对密度的影响；干扰项D利用了材料科学中常见的单位换算陷阱，将pm单位错误转换为nm时保留过多小数位。所有干扰项都针对AI模型在材料参数计算中可能出现的系统性错误设计。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1136, "question": "Solid solution strengthening", "answer": "Solid solution strengthening: When a solid solution is formed, the solvent lattice becomes distorted due to the dissolution of solute atoms. The stress field of the solute atoms interacts with dislocations, hindering their movement and increasing the resistance to dislocation motion. This results in a critical resolved shear stress much higher than that of pure metals, making the activation of slip systems more difficult compared to pure metals. Consequently, the material's resistance to plastic deformation increases, leading to higher hardness and strength, while plasticity and toughness decrease. This phenomenon is known as solid solution strengthening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对“固溶强化”这一现象进行详细的文字解释和论述，答案提供了完整的定义、机制和影响，符合简答题的特征。 | 知识层次: 题目要求解释固溶强化的机理，涉及溶质原子与位错的相互作用、临界分切应力的变化以及对材料性能的影响等多个方面的综合分析。这需要深入理解材料科学中的位错理论和强化机制，并进行推理分析，属于复杂分析的层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅要理解固溶强化的基本概念，还需要深入掌握其微观机理（如晶格畸变、位错运动阻碍等），并能综合分析其对材料力学性能的影响（强度提高、塑性韧性下降）。这种需要同时运用材料科学原理和力学性能知识的综合分析题，在选择题型中属于最复杂的类型，完全符合等级5\"复杂现象全面分析\"的标准。", "convertible": true, "correct_option": "Solid solution strengthening: When a solid solution is formed, the solvent lattice becomes distorted due to the dissolution of solute atoms. The stress field of the solute atoms interacts with dislocations, hindering their movement and increasing the resistance to dislocation motion. This results in a critical resolved shear stress much higher than that of pure metals, making the activation of slip systems more difficult compared to pure metals. Consequently, the material's resistance to plastic deformation increases, leading to higher hardness and strength, while plasticity and toughness decrease. This phenomenon is known as solid solution strengthening.", "choice_question": "下列关于固溶强化的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为'下列哪个是...'的形式的单选题。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening increases yield strength by impeding dislocation motion through lattice strain fields, while simultaneously reducing ductility due to restricted dislocation mobility", "B": "Solid solution strengthening primarily works by increasing the elastic modulus through solute-induced electron cloud distortion, making the material more resistant to elastic deformation", "C": "The effectiveness of solid solution strengthening is determined mainly by the difference in atomic radii between solute and solvent atoms, with larger differences always producing greater strengthening", "D": "Solid solution strengthening occurs when solute atoms preferentially segregate to grain boundaries, preventing grain boundary sliding and thus increasing high-temperature strength" }, "correct_answer": "A", "explanation": "Option A correctly describes the fundamental mechanism of solid solution strengthening through dislocation interaction with strain fields, and its effect on mechanical properties. Option B incorrectly associates the phenomenon with elastic modulus changes. Option C oversimplifies by ignoring the complex interactions beyond atomic size mismatch. Option D describes grain boundary strengthening rather than solid solution strengthening.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2235, "question": "Determine whether the following view is correct. (9) Normal grain growth is the consumption of small grains by large grains, while abnormal growth is the consumption of large grains by small grains.", "answer": "Incorrect. Normal grain growth is uniform growth driven by interface curvature, whereas abnormal growth is non-uniform growth where large grains consume small grains.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断一个陈述是否正确，答案明确指出了陈述的错误并给出了正确解释，符合判断题的特征。 | 知识层次: 题目考查对正常晶粒生长和异常晶粒生长这两个基本概念的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念正误判断，仅需记忆并区分正常晶粒生长和异常晶粒生长的基本定义即可作答。在选择题型中属于最简单的难度等级，不涉及复杂概念分析或比较。", "convertible": true, "correct_option": "Incorrect. Normal grain growth is uniform growth driven by interface curvature, whereas abnormal growth is non-uniform growth where large grains consume small grains.", "choice_question": "Determine whether the following view is correct. (9) Normal grain growth is the consumption of small grains by large grains, while abnormal growth is the consumption of large grains by small grains.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All phase transformations in materials science exhibit a clear nucleation and growth mechanism.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many phase transformations follow nucleation and growth mechanisms, some transformations like spinodal decomposition occur through continuous composition fluctuations without a distinct nucleation stage. This absolute statement fails to account for exceptions in transformation mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4202, "question": "What type(s) of bonding would be expected for solid xenon?", "answer": "For solid xenon, the bonding is van der Waals since xenon is an inert gas.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释固体氙的键合类型，答案提供了文字解释和论述，没有选项或计算要求。 | 知识层次: 题目考查对惰性气体固态时键合类型的基础概念记忆，仅需知道惰性气体通过范德华力形成固态这一基本原理即可作答，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即惰性气体固态时的键合类型。题目不涉及概念解释或复杂分析，只需识别出氙是惰性气体并回忆其固态键合方式为范德华力。因此属于最基本难度等级。", "convertible": true, "correct_option": "van der Waals", "choice_question": "What type of bonding would be expected for solid xenon?", "conversion_reason": "The answer is a standard term (van der Waals) and can be presented as a choice among other types of bonding.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "van der Waals", "B": "Metallic", "C": "Covalent", "D": "Ionic" }, "correct_answer": "A", "explanation": "Solid xenon is a noble gas solid where the atoms are held together by weak van der Waals forces (London dispersion forces). The incorrect options exploit common cognitive biases: B) Metallic exploits the 'shiny appearance' heuristic, C) Covalent plays on the tendency to associate solids with strong bonds, and D) Ionic capitalizes on the misconception that all solids must have ionic character. Advanced AI systems may overthink and select covalent bonding due to xenon's known ability to form compounds under extreme conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1741, "question": "According to the law of rational indices, the coordinate axes in a crystal structure should be selected in the direction of . a．mutually perpendicular b．close-packed planes c．rows in the crystal", "answer": "c", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项a、b、c中选择正确答案，符合选择题的特征 | 知识层次: 题目考查晶体结构中坐标轴选择方向的基本概念记忆，属于对\"有理指数定律\"基础知识的直接考察。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然考察的是基础概念记忆，但需要学生对\"law of rational indices\"有基本理解，并能区分\"rows in the crystal\"与其他选项的区别。相比直接记忆定义（等级1），此题需要一定的概念辨析能力（等级2），但不需要复杂的分析推理（等级3）。", "convertible": true, "correct_option": "rows in the crystal", "choice_question": "According to the law of rational indices, the coordinate axes in a crystal structure should be selected in the direction of .", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The direction with the highest atomic packing density", "B": "The direction perpendicular to cleavage planes", "C": "The direction parallel to Burgers vectors", "D": "The direction of maximum thermal conductivity" }, "correct_answer": "A", "explanation": "The law of rational indices requires coordinate axes to be aligned with crystallographic directions where atomic rows are most densely packed (A). B exploits the common misconception that cleavage planes determine axes, while C uses dislocation theory terminology to mislead. D leverages thermal properties knowledge that is irrelevant to crystallographic indexing.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2422, "question": "Assuming that at 1000°C, atoms diffuse through an Al2O3 crystal a distance x in 3h, estimate the time required for Al atoms to diffuse through the same Al2O3 crystal a distance of 9x.", "answer": "Since the diffusion distance is proportional to the square root of time, when the diffusion distance is 9x, the required time is t2 = (9x)^2 / x^2 * 3h = 243h.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，通过扩散距离与时间的关系公式来估算所需时间。答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目主要考查对扩散距离与时间平方根关系的理解，并直接套用公式进行计算。虽然需要理解扩散的基本原理，但计算过程相对简单，属于基本公式的直接应用。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解扩散距离与时间的关系（平方根关系），但解题步骤相对直接，仅需套用公式并进行简单计算即可得出答案。不需要复杂的分析或多步骤推理，因此在选择题型内属于等级2难度。", "convertible": true, "correct_option": "243h", "choice_question": "Assuming that at 1000°C, atoms diffuse through an Al2O3 crystal a distance x in 3h, estimate the time required for Al atoms to diffuse through the same Al2O3 crystal a distance of 9x.", "conversion_reason": "The calculation question has a definite numerical answer, which can be converted into a multiple-choice format with the correct option being the calculated result.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "243h", "B": "27h", "C": "81h", "D": "9h" }, "correct_answer": "A", "explanation": "扩散距离与时间的关系遵循x²=Dt，因此距离增加9倍需要81倍的时间（9²=81）。原始时间为3h，所以正确答案是81×3=243h。干扰项B利用了线性关系的错误直觉（9x对应27h），C遗漏了原始3h的乘法关系（仅计算81h），D则是完全忽略了平方关系。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3175, "question": "Estimate the strain energy of a 1cm long edge dislocation (r0=1nm, R=1cm, μ=5×10^10Pa, b=0.25nm, ν=1/3)", "answer": "The strain energy per unit length of an edge dislocation is WE=(W/L)E=μb^2/[4π(1−ν)]ln(R/r0). The strain energy of a 1cm edge dislocation is WI={[5×10^10×(0.25×10^-9)^2]/[4×3.14×(1−1/3)]}×10^-2×ln[(1×10^-2)/(1×10^-9)]=6×10^-11J.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解应变能，答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括公式应用、单位转换和对数运算，同时需要理解应变能的概念和位错的基本性质。虽然不涉及复杂的综合分析或创新应用，但比简单的直接套用公式更复杂。 | 难度: 在选择题中属于中等偏上难度，需要理解应变能公式并正确代入多个变量进行计算，包括对数运算和单位转换。虽然题目提供了公式，但涉及多个步骤的综合计算和对数函数的应用，对考生的计算能力和概念理解有一定要求。", "convertible": true, "correct_option": "6×10^-11J", "choice_question": "Estimate the strain energy of a 1cm long edge dislocation (r0=1nm, R=1cm, μ=5×10^10Pa, b=0.25nm, ν=1/3). The strain energy is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6×10^-11J", "B": "1.5×10^-10J", "C": "3.75×10^-12J", "D": "2.4×10^-9J" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula for strain energy of an edge dislocation: E = (μb²L/4π(1-ν)) * ln(R/r0). Plugging in the given values (μ=5×10^10Pa, b=0.25nm, L=1cm, ν=1/3, R=1cm, r0=1nm) yields 6×10^-11J. Option B is a common error from forgetting the (1-ν) term in the denominator. Option C results from incorrectly using the core radius (r0) as the outer cutoff radius (R). Option D is obtained by mistakenly using Young's modulus instead of shear modulus (μ), exploiting the elastic modulus confusion trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 459, "question": "Given that the density of GaAs is ${5.307\\\\mathrm{g/cm}^{3}}$, the atomic weights of Ga and As are 69.72 and 74.92 respectively, and its crystal structure is cubic $\\\\mathbf{Z}\\\\mathbf{n}\\\\mathbf{S}$ type, find the unit cell parameter of GaAs.", "answer": "Constituent composition: $w_{\\\\mathrm{F}}={\\\\frac{0.77-0.65}{0.77-0.022}}\\\\times100\\\\%=16.0\\\\%$ $w_{\\\\mathrm{P}}=1-16.0\\\\%=84.0\\\\%$ Phase composition: $w_{\\\\alpha}=\\\\frac{6.69-0.65}{6.69-0.22}\\\\times100\\\\%=90.6\\\\%$ WFe,c = 1 - 90.6% = 9.4% VII. The crystal structure of GaAs is cubic $\\\\mathbf{Z}\\\\mathbf{n}\\\\mathbf{S}$ type, so there are 4 $\\\\mathrm{Ga}$ and 4 $\\\\mathbf{As}$ in the unit cell. Unit cell weight $W={\\\\frac{\\\\left(M_{A}+M_{B}\\\\right)\\\\times4}{N}}={\\\\frac{(69.72+74.92)\\\\times4{\\\\mathrm{g/mol}}}{6.022\\\\times10^{23}/{\\\\mathrm{mol}}}}=96.07\\\\times10^{-23}{\\\\mathrm{g}}$ Unit cell volume $V=a^{3},\\\\rho=\\\\frac{W}{a^{3}}$ Unit cell parameter $a=\\\\sqrt[3]{\\\\frac{W}{\\\\rho}}=\\\\sqrt[3]{\\\\frac{96.07\\\\times10^{-23}}{5.307}}\\\\mathrm{{cm}}=0.5657\\\\times10^{-7}\\\\mathrm{{cm}}=0.5657\\\\mathrm{{nm}}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的密度、原子重量和晶体结构信息，应用公式计算GaAs的晶胞参数。解答过程涉及数值计算和公式应用，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括单位晶胞重量、体积的计算，以及密度的应用，涉及多个概念的综合运用和关联。虽然计算过程较为直接，但需要理解晶体结构、原子量和密度之间的关系，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要综合运用密度计算、晶体结构知识、单位换算等多步骤计算过程。题目要求考生理解立方ZnS型晶体结构（包含4个Ga和4个As原子），并能正确计算晶胞质量和体积，最终推导晶格常数。虽然提供了计算公式，但涉及多个物理概念的串联应用和单位转换，在选择题型中属于需要较强综合分析能力的题目。", "convertible": true, "correct_option": "0.5657 nm", "choice_question": "Given that the density of GaAs is ${5.307\\mathrm{g/cm}^{3}}$, the atomic weights of Ga and As are 69.72 and 74.92 respectively, and its crystal structure is cubic $\\mathbf{Z}\\mathbf{n}\\mathbf{S}$ type, the unit cell parameter of GaAs is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.5657 nm", "B": "0.5632 nm", "C": "0.5681 nm", "D": "0.5619 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.5657 nm) calculated using the density formula for zinc blende structure considering 4 formula units per unit cell. Option B (0.5632 nm) is a common error from misapplying atomic packing factor. Option C (0.5681 nm) results from incorrect assumption of 2 formula units per cell. Option D (0.5619 nm) arises from neglecting the mixed ionic-covalent bonding character of GaAs.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4210, "question": "Calculate the radius of an iridium atom, given that Ir has an FCC crystal structure, a density of 22.4g / {cm}^{3}, and an atomic weight of 192.2g / mol.", "answer": "the radius of an iridium atom is 0.136nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铱原子的半径，答案是一个具体的数值结果（0.136nm），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括利用FCC晶体结构的几何关系、密度和原子重量的关系，以及单位转换等综合分析步骤。虽然不涉及复杂的推理分析或创新应用，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解FCC晶体结构、密度与原子半径的关系，并进行多步计算。虽然题目给出了正确选项，但解题过程涉及单位换算、晶胞体积计算、原子半径推导等综合步骤，对概念掌握和计算能力要求较高。", "convertible": true, "correct_option": "0.136nm", "choice_question": "Given that Ir has an FCC crystal structure, a density of 22.4g/cm³, and an atomic weight of 192.2g/mol, the radius of an iridium atom is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible but incorrect values.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.136nm", "B": "0.143nm (BCC误用值)", "C": "0.128nm (忽略堆积因子计算错误)", "D": "0.152nm (单位换算陷阱)" }, "correct_answer": "A", "explanation": "正确答案A通过FCC结构正确计算原子半径。干扰项B利用FCC/BCC结构混淆的常见错误；C项通过省略堆积因子计算诱导错误；D项设置nm/Å单位换算陷阱。这些干扰项都针对AI在材料参数关联和单位敏感性方面的弱点设计。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 292, "question": "Analyze the effect of undercooling variation on the driving force during solid-state phase transformation", "answer": "Undercooling is the difference between the critical phase transformation temperature and the actual transformation temperature. The thermodynamic condition for phase transformation nucleation requires undercooling. The relationship between the driving force ΔG and undercooling ΔT is: ΔGg=-Lν(ΔT/T0)T, which further illustrates the thermodynamic condition for nucleation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析过冷度变化对固态相变驱动力的影响，需要文字解释和论述，答案也提供了详细的文字说明和公式解释，符合简答题的特征。 | 知识层次: 题目要求分析过冷度变化对固态相变驱动力的影响，涉及热力学条件的理解和推导，需要综合运用相变理论、热力学公式和机理解释，思维过程深度较高。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求分析过冷度变化对固态相变驱动力的影响，涉及复杂的热力学条件和机理解释。正确选项不仅需要理解过冷度的定义（临界相变温度与实际相变温度的差值），还需要掌握驱动力的计算公式ΔGg=-Lν(ΔT/T0)T，并能解释其热力学意义。这要求考生具备综合运用知识、推理分析和机理解释的能力，属于复杂现象的全面分析层次。因此，在选择题型中属于最高难度等级。", "convertible": true, "correct_option": "Undercooling is the difference between the critical phase transformation temperature and the actual transformation temperature. The thermodynamic condition for phase transformation nucleation requires undercooling. The relationship between the driving force ΔG and undercooling ΔT is: ΔGg=-Lν(ΔT/T0)T, which further illustrates the thermodynamic condition for nucleation.", "choice_question": "Which of the following best describes the effect of undercooling variation on the driving force during solid-state phase transformation?", "conversion_reason": "The answer is a standard explanation that can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best description of the effect.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The driving force increases quadratically with undercooling, as described by ΔG = -k(ΔT)^2 where k is a material-specific constant", "B": "Undercooling has no effect on driving force since solid-state transformations are diffusion-controlled rather than thermally activated", "C": "The relationship follows an inverse logarithmic dependence: ΔG = -Rln(1+ΔT/T0) where R is the gas constant", "D": "Driving force shows a linear dependence on undercooling only below a critical temperature threshold Tc" }, "correct_answer": "A", "explanation": "The correct answer is A because the driving force for solid-state phase transformation does indeed increase with the square of undercooling, reflecting the thermodynamic relationship between free energy change and temperature difference. Option B exploits the common confusion between transformation mechanisms and thermodynamic driving forces. Option C uses a plausible-looking logarithmic form that actually describes reaction kinetics rather than driving force. Option D creates a false threshold effect that doesn't exist in classical nucleation theory.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1791, "question": "Conditions necessary for mud peptization", "answer": "① The medium must be alkaline, ② Monovalent alkali metal cations must exchange with the higher-valent ions originally adsorbed on the clay, ③ Polymerization of anions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列出泥浆胶溶的必要条件，答案以文字解释和论述的形式给出，没有提供选项或需要计算，符合简答题的特征。 | 知识层次: 题目考查的是泥浆胶溶作用所需条件的基本概念记忆，包括碱性介质、单价碱金属阳离子交换和高价阴离子聚合等基本原理，属于基础概念的记忆和理解层面。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个条件（碱性介质、单价阳离子交换、阴离子聚合），但每个条件都是基础概念的直接应用，不需要复杂的推理或跨概念整合。学生只需准确记忆泥浆胶溶作用的三个必要条件即可作答，属于\"概念解释和描述\"层级。", "convertible": true, "correct_option": "The medium must be alkaline, Monovalent alkali metal cations must exchange with the higher-valent ions originally adsorbed on the clay, Polymerization of anions.", "choice_question": "Which of the following are the necessary conditions for mud peptization?", "conversion_reason": "The answer is a standard set of conditions that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The medium must be alkaline", "B": "High ionic strength solution is required", "C": "Presence of divalent cations enhances peptization", "D": "Acidic conditions promote clay particle dispersion" }, "correct_answer": "A", "explanation": "The correct answer is A because alkaline conditions are essential for maintaining negative charges on clay particles, facilitating peptization. Option B is incorrect as high ionic strength actually causes flocculation. Option C is a reversal trap - divalent cations cause flocculation, not peptization. Option D exploits a common misconception where acidic conditions are mistakenly associated with dispersion, when in reality they promote particle aggregation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2807, "question": "Explain why the diffusion activation energy of polycrystals is lower than that of single crystals.", "answer": "Polycrystals have grain boundaries, and the 'short-circuit' diffusion effect of grain boundaries increases the diffusion rate, thus resulting in a lower diffusion activation energy. The diffusion in single crystals is purely bulk diffusion, which has a higher activation energy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释多晶体的扩散激活能低于单晶体的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要解释多晶和单晶扩散激活能差异的机理，涉及对晶界扩散效应的理解和综合分析，属于对材料科学中扩散机制的深入分析和解释。 | 难度: 在选择题型内，该题目属于机理深度解释难度。题目要求考生不仅理解扩散激活能的基本概念，还需要掌握多晶体和单晶体在扩散机制上的差异，特别是晶界“短路”扩散效应的原理。这需要考生具备较高的知识综合运用能力和机理解释能力，能够将多个知识点联系起来进行推理分析。虽然题目提供了正确选项，但选项本身包含了较为复杂的机理描述，对考生的理解深度有较高要求。", "convertible": true, "correct_option": "Polycrystals have grain boundaries, and the 'short-circuit' diffusion effect of grain boundaries increases the diffusion rate, thus resulting in a lower diffusion activation energy. The diffusion in single crystals is purely bulk diffusion, which has a higher activation energy.", "choice_question": "Why is the diffusion activation energy of polycrystals lower than that of single crystals?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The presence of grain boundaries provides lower-energy pathways for atomic diffusion", "B": "Polycrystals have higher dislocation density which enhances diffusion kinetics", "C": "Single crystals exhibit stronger atomic bonding at all crystallographic orientations", "D": "The random orientation of grains in polycrystals reduces the overall energy barrier" }, "correct_answer": "A", "explanation": "Correct answer A identifies the key role of grain boundaries as low-energy diffusion pathways. Option B is a cognitive bias trap - while dislocations can enhance diffusion, they're not the primary reason for lower activation energy in polycrystals. Option C exploits material intuition by suggesting bonding strength differences that don't actually exist between single and polycrystals. Option D sounds plausible but misattributes the effect to grain orientation rather than boundary structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3238, "question": "The main mechanism of high-temperature recovery is A. Dislocation slip and cross-slip B. Dislocation climb and polygonization C. Polygonization and subgrain coalescence D. Bulge nucleation and subgrain coalescence", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从选项A、B、C、D中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查对高温回复机制的理解和应用，需要将多个概念（位错攀移和多边化）关联起来进行分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求考生理解高温回复的主要机制，还需要区分多个相似但不同的概念（如位错滑移、交叉滑移、位错攀移、多边形化等）。解题过程涉及综合分析多个材料科学原理，并准确关联到高温回复的具体机制。此外，选项中的术语和概念需要较深的理解才能正确判断，属于中等应用层次的多步分析和概念关联题目。", "convertible": true, "correct_option": "Dislocation climb and polygonization", "choice_question": "The main mechanism of high-temperature recovery is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dislocation slip and cross-slip", "B": "Dislocation climb and polygonization", "C": "Polygonization and subgrain coalescence", "D": "Bulge nucleation and subgrain coalescence" }, "correct_answer": "B", "explanation": "The correct answer is B because dislocation climb (enabled by vacancy diffusion at high temperatures) and polygonization (rearrangement of dislocations into low-energy configurations) are the primary mechanisms of high-temperature recovery. Option A is a strong distractor as dislocation slip/cross-slip are dominant at lower temperatures, exploiting the AI's tendency to associate dislocation motion with recovery. Option C combines a correct element (polygonization) with an incorrect one (subgrain coalescence which occurs during recrystallization), targeting the AI's pattern-matching weakness. Option D describes dynamic recrystallization mechanisms, exploiting confusion between recovery and recrystallization processes that AI systems often struggle to distinguish.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4441, "question": "Why may there be significant scatter in the fracture strength for some given ceramic material?", "answer": "There may be significant scatter in the fracture strength for some given ceramic material because the fracture strength depends on the probability of the existence of a flaw that is capable of initiating a crack; this probability varies from specimen to specimen of the same material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对陶瓷材料断裂强度存在显著分散性的原因进行文字解释和论述，答案提供了详细的解释而非选择、判断或计算。 | 知识层次: 题目要求解释陶瓷材料断裂强度存在显著分散性的原因，涉及对断裂机理的理解和分析。需要综合运用概率统计、缺陷分布和裂纹萌生等概念，进行推理和解释，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解陶瓷材料断裂强度的基本概念，还需要深入分析断裂强度与缺陷概率之间的复杂关系，并能够解释不同样本间强度差异的机理。这需要综合运用材料科学知识、概率分析以及断裂力学原理，进行多层次的推理和解释。因此，该题目在选择题型内属于复杂现象全面分析的难度等级。", "convertible": true, "correct_option": "There may be significant scatter in the fracture strength for some given ceramic material because the fracture strength depends on the probability of the existence of a flaw that is capable of initiating a crack; this probability varies from specimen to specimen of the same material.", "choice_question": "Why may there be significant scatter in the fracture strength for some given ceramic material?", "conversion_reason": "The answer is a standard explanation that can be directly used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Due to the probabilistic nature of critical flaw distribution in brittle ceramics", "B": "Because ceramic materials exhibit significant plastic deformation before fracture", "C": "Due to variations in elastic modulus between different specimens", "D": "Because the fracture strength is primarily determined by grain boundary diffusion rates" }, "correct_answer": "A", "explanation": "The correct answer is A because ceramic fracture strength is controlled by the statistical distribution of flaws that act as stress concentrators. Option B is incorrect as ceramics are brittle materials that show negligible plastic deformation. Option C is a cognitive bias trap using a real material property (elastic modulus) that doesn't actually vary significantly between specimens of the same material. Option D is a professional intuition trap that incorrectly applies a high-temperature deformation mechanism to room-temperature fracture behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1439, "question": "The commonly used method for refining grains in casting processes is (21)", "answer": "(21) stirring or vibration", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个具体的方法名称（stirring or vibration），属于需要简短文字回答的简答题类型 | 知识层次: 题目考查的是铸造过程中细化晶粒的常用方法，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对铸造工艺中细化晶粒常用方法的基础概念记忆，属于最基础的定义简答级别。正确选项直接对应教材中的标准答案，无需复杂推理或概念比较。", "convertible": true, "correct_option": "stirring or vibration", "choice_question": "The commonly used method for refining grains in casting processes is:", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Stirring or vibration", "B": "Rapid quenching", "C": "Alloying with grain refiners", "D": "Applying magnetic fields during solidification" }, "correct_answer": "A", "explanation": "The correct answer is A because mechanical stirring or vibration physically breaks up dendrites and promotes heterogeneous nucleation. B is incorrect because rapid quenching primarily affects grain size through undercooling, not refinement during casting. C is a strong distractor as grain refiners are indeed used, but this is an additive method rather than the 'commonly used' mechanical approach. D exploits advanced material processing knowledge by presenting a real but less common technique that sounds scientifically plausible.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2480, "question": "If a nucleus with a radius of 2×10^-9 m is to be formed, what should the dislocation density at the nucleation site be? (G=4×10^10 Pa, b=0.25×10^-9 m)", "answer": "If a nucleus with a radius of 2×10^-9 m is to be formed, the required dislocation density ρ is: ρ = 4γ/(r*Gb^2) = (4×0.5)/(2×10^-9×4×10^10×(0.25×10^-9)^2) m^-2 = 4×10^17 m^-2.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解所需的位错密度，答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及公式应用和概念关联（如位错密度、核形成半径、剪切模量等），但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念（如位错密度、核形成半径、材料常数等）并进行多步计算和综合分析。题目涉及公式推导和单位换算，但选项提供了明确的解题路径，降低了部分难度。", "convertible": true, "correct_option": "4×10^17 m^-2", "choice_question": "If a nucleus with a radius of 2×10^-9 m is to be formed, what should the dislocation density at the nucleation site be? (G=4×10^10 Pa, b=0.25×10^-9 m)", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4×10^17 m^-2", "B": "1.6×10^17 m^-2", "C": "2.5×10^18 m^-2", "D": "6.4×10^16 m^-2" }, "correct_answer": "A", "explanation": "正确答案A基于经典位错理论计算得出：ρ=16πγ/(Gb^2r)，其中γ≈Gb/4。干扰项B错误地使用了弹性模量而非剪切模量计算；C是常见错误，源于对临界半径公式的误解；D则是单位换算错误的结果，利用了材料科学中常见的数量级混淆陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2894, "question": "What is co-condensation?", "answer": "The polycondensation reaction involving two or more monomers is called co-condensation polymerization, abbreviated as co-condensation, and the resulting polymer composition differs from the monomers.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"co-condensation\"进行解释和论述，答案提供了详细的文字说明，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即对co-condensation的定义和基本原理的掌握。 | 难度: 在选择题型中，该题目仅考察对\"co-condensation\"这一基础概念的定义记忆，属于最基本的概念简答。题目直接给出了定义描述，不需要进行任何概念比较或复杂推理，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The polycondensation reaction involving two or more monomers is called co-condensation polymerization, abbreviated as co-condensation, and the resulting polymer composition differs from the monomers.", "choice_question": "Which of the following best describes co-condensation?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A polymerization process where two different monomers simultaneously undergo condensation reactions to form a copolymer", "B": "The simultaneous evaporation and condensation of solvent molecules during polymer synthesis", "C": "A special case of phase separation where polymer chains condense into coacervate droplets", "D": "The co-deposition of vaporized materials in thin film fabrication processes" }, "correct_answer": "A", "explanation": "The correct answer is A because co-condensation specifically refers to the joint condensation polymerization of two or more monomers forming a copolymer. Option B exploits confusion with solvent removal processes. Option C uses a similar-sounding but unrelated phase separation phenomenon. Option D borrows terminology from thin film deposition to create a plausible-sounding but incorrect alternative.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2590, "question": "When the crystal around an edge dislocation contains an excess of vacancies, how will the dislocation climb?", "answer": "Positive climb", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释位错攀移的行为，需要文字解释和论述，答案\"Positive climb\"是一个简短的文字回答，而不是从多个选项中选择或判断对错 | 知识层次: 题目涉及位错攀移机制的分析，需要理解空位对位错运动的影响，并进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Positive climb", "choice_question": "When the crystal around an edge dislocation contains an excess of vacancies, how will the dislocation climb?", "conversion_reason": "The answer is a standard term (Positive climb), which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Positive climb", "B": "Negative climb", "C": "No climb occurs", "D": "Lateral slip" }, "correct_answer": "A", "explanation": "The correct answer is A because an excess of vacancies enables the dislocation to move out of its slip plane by absorbing vacancies, resulting in positive climb. Option B is a cognitive bias trap, as negative climb would require an excess of interstitials. Option C exploits the common misconception that dislocations only move in their slip plane. Option D is a professional intuition trap, as slip is a different mechanism unrelated to vacancy-assisted climb.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1915, "question": "When 20 mol% YF3 is added to CaF2 to form a solid solution, the experimentally measured density of the solid solution is 3.64 g/cm3, and the lattice parameter at this time is a=0.55 nm. Calculate and determine the type of this solid solution. (The atomic weights are Y 88.9, Ca 40.0, F 19.0).", "answer": "The unit cell of the fluorite-type crystal structure contains 4 CaF2, ρ_vacancy=3.34 g/cm3; ρ_interstitial=3.65 g/cm3; ρ_interstitial is close to the measured ρ=3.65 g/cm3, so under these conditions, an interstitial solid solution is formed.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（如密度、晶格参数等）并应用相关公式来确定固溶体的类型。答案中包含了具体的计算过程和结果比较，符合计算题的特征。 | 知识层次: 题目涉及多步计算（密度计算、晶格参数分析）、概念关联（固溶体类型判断）和综合分析（比较计算值与实验值）。虽然不涉及复杂的机理分析或创新设计，但需要将多个知识点和计算步骤结合起来解决问题，超出了简单应用的范畴。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念并进行比较分析。题目涉及固体溶液类型的判断，需要计算理论密度并与实验值比较。解题步骤包括：", "convertible": true, "correct_option": "an interstitial solid solution is formed", "choice_question": "When 20 mol% YF3 is added to CaF2 to form a solid solution, the experimentally measured density of the solid solution is 3.64 g/cm3, and the lattice parameter at this time is a=0.55 nm. The type of this solid solution is:", "conversion_reason": "The original question is a calculation problem with a definitive answer that can be presented as a choice among options. The answer is a standard term describing the type of solid solution formed, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "an interstitial solid solution is formed", "B": "a substitutional solid solution with cation vacancies", "C": "a substitutional solid solution with anion vacancies", "D": "a simple substitutional solid solution without defects" }, "correct_answer": "A", "explanation": "The correct answer is A because Y3+ ions are too large to substitute for Ca2+ in the CaF2 lattice, forcing them into interstitial positions while creating fluoride ion vacancies to maintain charge neutrality. Option B exploits the common misconception that cation vacancies must form when trivalent ions substitute for divalent ones. Option C plays on the intuitive but incorrect assumption that anion vacancies would dominate in a fluoride system. Option D is a classic oversimplification trap that ignores the size mismatch and charge imbalance issues.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1030, "question": "Coordination number", "answer": "Coordination number: In a crystal structure, the number of atoms that are adjacent to and equidistant from any given atom.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Coordination number\"进行定义和解释，需要文字描述和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对配位数这一基本概念的定义和记忆，属于基础概念的理解层面，不涉及应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别配位数的基本定义，属于最基础的概念记忆层次。题目没有涉及复杂概念体系或需要分析推理的步骤，仅需直接回忆定义即可作答，因此属于难度等级1。", "convertible": true, "correct_option": "In a crystal structure, the number of atoms that are adjacent to and equidistant from any given atom.", "choice_question": "Which of the following best defines the term 'Coordination number'?", "conversion_reason": "The answer is a standard definition of a scientific term, which can be easily converted into a multiple-choice question format by providing the correct definition as one of the options and other plausible but incorrect definitions as distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In a crystal structure, the number of atoms that are adjacent to and equidistant from any given atom", "B": "The number of electron pairs shared between a central metal ion and its ligands in a coordination complex", "C": "The maximum number of nearest neighbor atoms possible in a close-packed crystal structure", "D": "The number of atomic orbitals hybridized to form molecular orbitals in metallic bonding" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines coordination number in crystallography. Option B is a cognitive bias trap, confusing crystallographic coordination number with coordination chemistry terminology. Option C is a professional intuition trap, incorrectly limiting the definition to close-packed structures only. Option D is a multi-level verification trap, mixing concepts of metallic bonding with coordination geometry.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3331, "question": "After quenching T8 steel wire to 20°C and holding, indicate its phases and composition.", "answer": "M+A′ (w_C=0.77% in M, A′)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述淬火后T8钢的相组成和成分，需要文字解释和论述，答案给出了具体的相和成分，属于简答题类型。 | 知识层次: 题目要求分析T8钢在特定热处理条件下的相组成和成分，需要理解钢的相变原理和相图知识，并能够将理论应用于具体材料和处理条件。这涉及多步概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解T8钢的相变过程、淬火后的组织组成以及碳含量的分配。题目要求考生综合运用相图知识和热处理原理，分析淬火后钢中的马氏体（M）和残余奥氏体（A′）的组成及其碳含量。虽然题目提供了正确选项，但考生仍需具备一定的知识深度和综合分析能力才能正确理解和选择答案。", "convertible": true, "correct_option": "M+A′ (w_C=0.77% in M, A′)", "choice_question": "After quenching T8 steel wire to 20°C and holding, which of the following indicates its phases and composition?", "conversion_reason": "The answer is a standard terminology and can be converted into a multiple-choice format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "M+A′ (w_C=0.77% in M, A′)", "B": "M+B (w_C=0.8% in M, B)", "C": "M+P (w_C=0.77% in M, P)", "D": "M (w_C=0.8% in M)" }, "correct_answer": "A", "explanation": "The correct answer is A because T8 steel (eutectoid composition) when quenched to 20°C forms martensite (M) with retained austenite (A′). The carbon content in martensite remains at the eutectoid composition of 0.77%. Option B is incorrect as bainite (B) does not form at room temperature. Option C is wrong because pearlite (P) requires slow cooling. Option D is partially correct but misses the retained austenite (A′) which is always present in quenched steels.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3399, "question": "How is the range of high, medium, and low carbon steels usually divided?", "answer": "High carbon steel: wC>0.60%, medium carbon steel: wC=0.25%~0.60%, low carbon steel: wC≤0.25%.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释高、中、低碳钢的范围划分，答案提供了具体的文字说明和数值范围，属于需要文字解释的简答题类型。 | 知识层次: 题目考查对高、中、低碳钢分类标准的基本概念记忆，属于定义性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆高、中、低碳钢的碳含量范围划分，属于基础定义简答。题目仅涉及单一知识点的直接回忆，无需解释或复杂分析，符合等级1的难度标准。", "convertible": true, "correct_option": "High carbon steel: wC>0.60%, medium carbon steel: wC=0.25%~0.60%, low carbon steel: wC≤0.25%", "choice_question": "How is the range of high, medium, and low carbon steels usually divided?", "conversion_reason": "The answer is a standard classification with clear boundaries, making it suitable for conversion to a multiple-choice question where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High carbon steel: wC>0.60%, medium carbon steel: wC=0.25%~0.60%, low carbon steel: wC≤0.25%", "B": "High carbon steel: wC>0.80%, medium carbon steel: wC=0.30%~0.80%, low carbon steel: wC≤0.30%", "C": "High carbon steel: wC>0.50%, medium carbon steel: wC=0.20%~0.50%, low carbon steel: wC≤0.20%", "D": "High carbon steel: wC>0.40%, medium carbon steel: wC=0.15%~0.40%, low carbon steel: wC≤0.15%" }, "correct_answer": "A", "explanation": "The correct classification follows the internationally accepted standard for carbon steel categorization. Option B uses higher thresholds that might confuse AI by resembling alloy steel classifications. Option C employs a common 0.5% threshold that appears plausible but is incorrect for plain carbon steels. Option D mimics stainless steel classifications, exploiting material category confusion. All incorrect options leverage the fact that different material systems use similar but distinct classification boundaries.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2944, "question": "In a binary system composed of A and B, when α and β phases are in equilibrium, the relationship between composition (x) and free energy (G) for the two components is (A) $G^{\\\\alpha}=G^{\\\\beta}$ (B) $\\\\mathrm{d}G^{\\\\circ}/\\\\mathrm{d}x=\\\\mathrm{d}G^{\\\\beta}/\\\\mathrm{d}x$ (C) $G_{\\\\tt A}=G_{\\\\tt B}$", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从多个选项（A、B、C）中选择一个正确答案，符合选择题的特征。 | 知识层次: 题目考查二元系统中两相平衡时自由能与成分关系的理解，需要掌握自由能曲线的概念及其在相平衡中的应用，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目涉及二元系统中α和β相平衡时的自由能关系，需要理解热力学平衡条件（化学势相等）及其数学表达形式。其次，正确选项B要求考生掌握自由能对成分的偏导数（即化学势的斜率）在相平衡时必须相等的原理，这需要将热力学概念与数学微分运算相结合。此外，题目中的干扰项A和C分别设置了常见错误选项（直接比较相自由能或组分自由能），增加了判断难度。综合来看，该题需要考生在多步概念关联和综合分析的基础上才能正确选择，符合等级4\"复杂分析过程的判断\"的标准。", "convertible": true, "correct_option": "$\\mathrm{d}G^{\\circ}/\\mathrm{d}x=\\mathrm{d}G^{\\beta}/\\mathrm{d}x$", "choice_question": "In a binary system composed of A and B, when α and β phases are in equilibrium, the relationship between composition (x) and free energy (G) for the two components is:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed to the question itself.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The chemical potentials of component B must be equal in both phases", "B": "The total free energy of the system must be minimized", "C": "The molar volumes of both phases must be identical", "D": "The entropy of mixing must be maximized in both phases" }, "correct_answer": "A", "explanation": "The correct answer is A because at equilibrium, the chemical potential of each component must be equal in all coexisting phases (Gibbs phase rule). Option B is a general thermodynamic principle but not the specific condition for phase equilibrium. Option C exploits confusion with mechanical equilibrium conditions. Option D uses the common misconception about entropy maximization being the sole driving force, ignoring chemical potential equality requirement.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1249, "question": "What are the usual slip planes for face-centered cubic metals?", "answer": "{111}", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要回答面心立方金属的常见滑移面，答案形式为简短的文本（{111}），不需要选择、判断或计算 | 知识层次: 题目考查面心立方金属常见滑移面的记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆面心立方金属的常见滑移面{111}，属于基础概念记忆层次。题目不涉及概念解释或复杂体系阐述，仅需直接回忆单一知识点即可作答，因此属于最简单的难度等级1。", "convertible": true, "correct_option": "{111}", "choice_question": "What are the usual slip planes for face-centered cubic metals?", "conversion_reason": "The answer is a standard term in materials science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "{111}", "B": "{110}", "C": "{100}", "D": "{112}" }, "correct_answer": "A", "explanation": "The correct slip planes for FCC metals are {111} because these planes have the highest atomic packing density and the widest spacing between planes, making slip energetically favorable. Option B {110} is a common slip plane for body-centered cubic metals, exploiting the AI's potential confusion between crystal structures. Option C {100} appears plausible due to its high symmetry but has lower packing density in FCC. Option D {112} is a real FCC plane but not the primary slip system, creating a subtle distinction trap for AI systems that might overgeneralize from limited data.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3780, "question": "Based on Hume-Rothery's conditions, would the system Mo-Ta be expected to display unlimited solid solubility? Explain.", "answer": "Yes", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求基于Hume-Rothery条件解释Mo-Ta系统是否显示无限固溶性，需要文字解释和论述，而不仅仅是简单的选择或判断。答案\"Yes\"只是结论部分，完整的解答还需要解释为什么符合Hume-Rothery条件。 | 知识层次: 题目要求基于Hume-Rothery规则分析Mo-Ta系统的固溶度，需要理解并应用多个条件（如原子尺寸、电负性、价电子浓度等）进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解Hume-Rothery规则中的多个条件（如原子尺寸差、晶体结构、电负性和价电子浓度），并将这些概念应用于Mo-Ta体系的分析。虽然不需要复杂的计算，但需要对概念有较深的理解和综合应用能力。", "convertible": true, "correct_option": "Yes", "choice_question": "Based on Hume-Rothery's conditions, would the system Mo-Ta be expected to display unlimited solid solubility?", "conversion_reason": "The answer is a straightforward 'Yes' or 'No' response, making it suitable for conversion to a multiple-choice format with clear options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, due to identical crystal structures and nearly identical atomic radii", "B": "No, because their electronegativity difference exceeds 15%", "C": "Only at high temperatures where diffusion overcomes size mismatch", "D": "No, due to significant differences in valence electron concentration" }, "correct_answer": "A", "explanation": "Correct: Mo-Ta meet all Hume-Rothery conditions (same BCC structure, 0.3% radius difference, same valence, negligible electronegativity difference). Distractors: B exploits AI's tendency to overvalue electronegativity (actual difference is only 0.1). C creates false temperature dependency. D misleads by suggesting VEC difference when both have 6 valence electrons.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4487, "question": "Is it possible to grind up and reuse phenol-formaldehyde? Why or why not?", "answer": "It is not possible to grind up and reuse phenol-formaldehyde because it is a network thermoset polymer and, therefore, is not amenable to remolding.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对酚醛树脂是否可以研磨和再利用进行解释和论述，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对热固性聚合物基本特性的记忆和理解，即酚醛树脂作为网络热固性聚合物无法通过简单粉碎和重熔再利用的性质。这属于基础概念的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆（酚醛树脂的定义和分类），但需要考生理解热固性聚合物的基本特性（不可重塑性）并应用这一知识来解释为什么酚醛树脂不能研磨后重复使用。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。", "convertible": true, "correct_option": "It is not possible to grind up and reuse phenol-formaldehyde because it is a network thermoset polymer and, therefore, is not amenable to remolding.", "choice_question": "Is it possible to grind up and reuse phenol-formaldehyde?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question format. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because phenol-formaldehyde is a thermoset polymer that forms irreversible crosslinks during curing", "B": "Yes, but only if the grinding process is performed below the glass transition temperature to prevent further crosslinking", "C": "Yes, because the phenolic rings can be chemically cleaved and reformed under high pressure", "D": "No, unless special catalysts are added during grinding to break the hydrogen bonds" }, "correct_answer": "A", "explanation": "The correct answer is A because phenol-formaldehyde is a classic thermoset polymer that forms permanent, irreversible crosslinks during curing, making it impossible to remelt or reshape. Option B is incorrect because while Tg is important for processing thermoplastics, it doesn't affect the fundamental irreversibility of thermoset crosslinks. Option C is misleading as it suggests a plausible-sounding but non-existent mechanism for breaking and reforming phenolic rings. Option D exploits confusion between hydrogen bonding (which is reversible) and the actual covalent crosslinks in this system.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2099, "question": "14. At 550°C, an aluminum-copper alloy solid solution with composition x_Cu=0.02 is quenched and then reheated to 100°C to precipitate θ phase (CuAl2). The θ phase forms many small particles dispersed in the alloy with an average particle spacing of 5.0 nm. Approximately how many particles are formed in 1 mm³ of the alloy?", "answer": "Approximately 8×10^24 particles/m³ (equivalent to 8×10^15 particles/mm³).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定在1 mm³合金中形成的θ相颗粒数量。答案给出了具体的数值结果，表明这是一个计算题。 | 知识层次: 题目需要进行多步计算和概念关联，包括理解固溶体、相变、粒子间距等概念，并应用这些概念进行数值计算。虽然不涉及复杂的推理分析或创新应用，但需要一定的综合分析能力来解决问题。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及多步计算和概念关联，包括固溶体、相变、粒子间距计算等。虽然题目提供了正确选项，但需要考生综合运用材料科学知识进行计算和推理，属于综合性计算问题。", "convertible": true, "correct_option": "8×10^15 particles/mm³", "choice_question": "At 550°C, an aluminum-copper alloy solid solution with composition x_Cu=0.02 is quenched and then reheated to 100°C to precipitate θ phase (CuAl2). The θ phase forms many small particles dispersed in the alloy with an average particle spacing of 5.0 nm. Approximately how many particles are formed in 1 mm³ of the alloy?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8×10^15 particles/mm³", "B": "2×10^18 particles/mm³", "C": "1.6×10^14 particles/mm³", "D": "4×10^16 particles/mm³" }, "correct_answer": "A", "explanation": "The correct answer is A (8×10^15 particles/mm³) calculated by considering the volume per particle (5 nm)^3 and converting units. Option B is a common error from misinterpreting particle spacing as diameter. Option C results from incorrect unit conversion (nm to mm). Option D comes from overestimating the CuAl2 phase fraction by neglecting the alloy's dilute composition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4580, "question": "Explain why no free electron is generated by the electron excitation involving an acceptor impurity atom.", "answer": "No free electron is generated by an electron excitation involving an acceptor impurity atom because the electron is excited from the valence band into the impurity level within the band gap; no free electron is introduced into the conduction band.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么在涉及受主杂质原子的电子激发过程中不会产生自由电子，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释电子激发过程中自由电子未产生的原因，涉及价带、杂质能级和导带之间的电子跃迁机制，需要综合运用半导体物理知识进行推理分析，属于对材料科学中掺杂效应的深度理解。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求深入理解半导体物理中的杂质能级和电子激发机制，需要综合运用能带理论、杂质态特性以及电子跃迁原理进行复杂分析。正确选项不仅涉及多个关键概念（价带、导带、杂质能级），还需要准确描述电子激发路径的限定条件（不进入导带）。这种题目在选择题中需要考生具备机理深度解释和复杂现象全面分析的能力，远超简单记忆或基础理解的层次。", "convertible": true, "correct_option": "No free electron is generated by an electron excitation involving an acceptor impurity atom because the electron is excited from the valence band into the impurity level within the band gap; no free electron is introduced into the conduction band.", "choice_question": "Why is no free electron generated by the electron excitation involving an acceptor impurity atom?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The excited electron remains bound to the acceptor ion, forming a localized state", "B": "The energy required exceeds the band gap, preventing transition to conduction band", "C": "Acceptor impurities create holes rather than free electrons in the valence band", "D": "The impurity level acts as a recombination center for electrons and holes" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental mechanism where the electron is excited into the acceptor level but remains bound. Distractors: B exploits energy threshold misconception, C uses valence band hole confusion (partially correct but irrelevant to excitation), D introduces recombination red herring. Advanced AIs may overthink and select D due to its plausible-sounding but contextually incorrect mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2255, "question": "Analyze the main reasons for dislocations promoting nucleation in the case where the composition of the new phase differs from that of the parent phase", "answer": "When the composition of the new phase differs from that of the parent phase, the segregation of solute atoms along dislocation lines (forming Cottrell atmospheres) facilitates the precipitation of the new phase and also promotes nucleation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析并解释位错促进新相成核的主要原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析位错促进新相形核的主要原因，涉及溶质原子在位错线上的偏聚（Cottrell气团）及其对新相析出的影响。这需要综合运用位错理论、相变原理和扩散知识，进行机理层面的解释和推理分析，属于较高层次的认知要求。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "When the composition of the new phase differs from that of the parent phase, the segregation of solute atoms along dislocation lines (forming Cottrell atmospheres) facilitates the precipitation of the new phase and also promotes nucleation.", "choice_question": "Analyze the main reasons for dislocations promoting nucleation in the case where the composition of the new phase differs from that of the parent phase. Which of the following is correct?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When the composition of the new phase differs from that of the parent phase, the segregation of solute atoms along dislocation lines (forming Cottrell atmospheres) facilitates the precipitation of the new phase and also promotes nucleation.", "B": "Dislocations act as preferential nucleation sites primarily due to their high strain energy, which lowers the activation energy barrier for nucleation regardless of compositional differences.", "C": "The difference in composition between phases creates a lattice mismatch that is accommodated by dislocations, making them ideal nucleation sites through purely geometric considerations.", "D": "Solute atoms preferentially decorate dislocation cores, creating local compositional fluctuations that mimic the new phase's structure but do not significantly affect nucleation kinetics." }, "correct_answer": "A", "explanation": "The correct answer A identifies the key role of Cottrell atmospheres in facilitating nucleation when compositional differences exist. Option B is incorrect because it oversimplifies the mechanism by ignoring the crucial role of solute segregation. Option C is a geometric trap that ignores the thermodynamic aspects of nucleation. Option D contains a subtle error by suggesting the decorated dislocations don't affect nucleation kinetics, which contradicts experimental evidence.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3203, "question": "According to solidification theory, what are the basic approaches to refining grains?", "answer": "From solidification theory, it is known that the number of grains per unit volume during crystallization, z, depends on two factors: the nucleation rate N and the crystal growth rate Vg, i.e., z∝N/Vg. The basic approaches include increasing undercooling, adding nucleating agents (modification treatment), and vibration crystallization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述基本的晶粒细化方法，答案提供了详细的文字解释和理论依据，符合简答题的特征。 | 知识层次: 题目要求从凝固理论出发，解释细化晶粒的基本方法，涉及对成核速率和晶体生长速率的理解，以及如何通过增加过冷度、添加形核剂和振动结晶等方法实现晶粒细化。这需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及凝固理论中的晶粒细化基本方法，要求考生掌握成核速率和晶体生长速率的关系，并能综合分析增加过冷度、添加成核剂（变质处理）和振动结晶等不同方法的作用。虽然不需要多步计算，但需要将多个概念关联起来进行综合分析，因此在选择题型中属于等级3的难度。", "convertible": true, "correct_option": "increasing undercooling, adding nucleating agents (modification treatment), and vibration crystallization", "choice_question": "According to solidification theory, what are the basic approaches to refining grains?", "conversion_reason": "The answer is a standard set of approaches that can be presented as options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "increasing undercooling, adding nucleating agents, and vibration crystallization", "B": "increasing cooling rate, adding alloying elements, and electromagnetic stirring", "C": "decreasing nucleation barrier, applying ultrasonic treatment, and thermal cycling", "D": "controlling solidification front velocity, introducing grain refiners, and mechanical agitation" }, "correct_answer": "A", "explanation": "The correct answer is A because these are the three fundamental approaches recognized in solidification theory for grain refinement. Option B is a cognitive bias trap - while increasing cooling rate and electromagnetic stirring are valid methods, adding alloying elements primarily affects composition not grain size. Option C exploits professional intuition by mixing valid (ultrasonic treatment) with incorrect concepts (thermal cycling is not a standard grain refinement method). Option D is a multi-level verification trap where all methods seem plausible but 'controlling solidification front velocity' is more about microstructure control than direct grain refinement.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 972, "question": "How does temperature affect atomic diffusion in metals or alloys?", "answer": "Temperature follows the relationship D=Doe-Q/RT, where an increase in temperature accelerates diffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释温度如何影响金属或合金中的原子扩散，需要文字解释和论述，而不是选择、判断或计算。答案提供了扩散系数与温度的关系，并解释了温度升高对扩散的影响，符合简答题的特征。 | 知识层次: 题目涉及扩散系数与温度关系的公式应用，需要理解阿伦尼乌斯方程中各参数的含义及其物理意义，并能够解释温度变化对扩散速率的影响机制。这属于中等应用层次，需要将基本概念与公式关联起来进行综合分析。 | 难度: 在选择题中属于中等难度，需要理解扩散系数与温度的关系公式D=Doe-Q/RT，并能够综合分析温度变化对扩散速率的影响。题目涉及中等应用层次的知识，要求考生进行概念关联和多步计算，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Temperature follows the relationship D=Doe-Q/RT, where an increase in temperature accelerates diffusion.", "choice_question": "How does temperature affect atomic diffusion in metals or alloys?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diffusion coefficient follows Arrhenius behavior with D=D0e^(-Q/RT), showing exponential temperature dependence", "B": "Atomic vibrations reduce diffusion barrier height Q at higher temperatures according to Q=Q0(1-αT)", "C": "Temperature affects only the pre-exponential factor D0 through thermal expansion effects", "D": "Diffusion becomes temperature-independent above the Debye temperature due to phonon saturation" }, "correct_answer": "A", "explanation": "Correct answer A reflects the fundamental Arrhenius relationship for diffusion. Option B introduces a plausible but incorrect temperature-dependent activation energy modification. Option C exploits the common oversight of D0's weak temperature dependence versus the dominant exponential term. Option D uses a sophisticated but misapplied concept of phonon saturation that doesn't actually eliminate temperature dependence in diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3245, "question": "The correct order of coordination numbers for the following alloy phases from small to large is A.SiC、NaCl、a-Fe、Cu B.a-Fe、SiC、Cu、NaClC.a-Fe、Cu、SiC、NaCl D.SiC、a=Fe、NaCl、Cu", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确的配位数顺序，答案形式为选项A，符合选择题的特征。 | 知识层次: 题目考查对合金相配位数顺序的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目需要考生理解和辨析不同合金相的配位数概念，并进行排序比较。虽然涉及多个材料的配位数记忆，但属于基础概念的理解和简单应用，不需要复杂的分析或深度推理。因此属于中等难度（等级2）。", "convertible": true, "correct_option": "A", "choice_question": "The correct order of coordination numbers for the following alloy phases from small to large is:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The stacking fault energy of pure Al is higher than that of Al-4.5%Cu alloy at room temperature", "B": "The stacking fault energy of pure Cu is lower than that of Cu-30%Zn alloy at 500°C", "C": "The stacking fault energy of austenitic stainless steel decreases with increasing Ni content", "D": "The stacking fault energy of HCP metals is generally higher than that of FCC metals with similar atomic bonding" }, "correct_answer": "A", "explanation": "Correct answer A exploits the fundamental principle that solute atoms generally reduce stacking fault energy (SFE). Option B reverses this relationship at elevated temperature where Zn's effect diminishes. Option C plays on the complex Ni-Cr interaction in stainless steels that actually increases SFE. Option D triggers the common misconception about crystal structure effects, ignoring that HCP metals typically have lower SFE due to their stacking sequence.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1211, "question": "What is the physical meaning of the equilibrium partition coefficient?", "answer": "This parameter reflects the partition coefficient of solute between solid and liquid phases and the degree of influence of solute on the alloy's melting point.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释平衡分配系数的物理意义，答案提供了文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查平衡分配系数的物理意义这一基本概念的理解和记忆，属于定义和基本原理的范畴，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项不仅要求考生知道平衡分配系数的定义，还需要理解其在材料科学中的具体物理意义，即溶质在固相和液相之间的分配情况以及对合金熔点的影响。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "This parameter reflects the partition coefficient of solute between solid and liquid phases and the degree of influence of solute on the alloy's melting point.", "choice_question": "What is the physical meaning of the equilibrium partition coefficient?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ratio of solute concentrations in solid and liquid phases at equilibrium, determining solute redistribution during solidification", "B": "The thermodynamic parameter describing solute solubility limits in crystalline lattices at room temperature", "C": "The diffusion coefficient ratio between solute atoms in liquid and solid phases during non-equilibrium cooling", "D": "The dimensionless number characterizing solute trapping efficiency at ultra-rapid solidification rates" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines the equilibrium partition coefficient's role in solute redistribution during solidification. Option B misleads by confusing equilibrium partitioning with solubility limits. Option C exploits confusion between partition coefficient and kinetic diffusion parameters. Option D creates a plausible-sounding but incorrect connection to rapid solidification phenomena, which actually involve non-equilibrium partitioning.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4792, "question": "For the following pair of polymers, do the following: (1) state whether it is possible to decide whether one polymer has a higher tensile strength than the other; (2) if this is possible, note which has the higher tensile strength and cite the reason(s) for your choice; and (3) if it is not possible to decide, state why. Linear and isotactic poly(vinyl chloride) with a weight-average molecular weight of 100,000 g/mol; branched and atactic poly(vinyl chloride) having a weight-average molecular weight of 75,000 g/mol", "answer": "Yes, it is possible. The linear and isotactic material will have the higher tensile strength. Both linearity and isotacticity favor a higher degree of crystallinity than do branching and atacticity; and tensile strength increases with increasing degree of crystallinity. Furthermore, the molecular weight of the linear/isotactic material is higher (100,000 g/mol versus 75,000 g/mol), and tensile strength increases with increasing molecular weight.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对两种聚合物的拉伸强度进行比较，并解释原因。答案需要文字解释和论述，而不是简单的选择或判断。题目没有提供选项，也不涉及计算，因此属于简答题。 | 知识层次: 题目要求比较两种聚合物的拉伸强度，并解释原因。这涉及到对聚合物结构（线性与支化、等规与无规）和分子量对性能影响的理解，需要综合分析多个因素（结晶度、分子量）对拉伸强度的共同作用。虽然不涉及复杂计算，但需要关联多个概念并进行逻辑推理。 | 难度: 在选择题中属于较高难度，需要综合比较两种聚合物的结构特征（线性/支化、等规/无规）和分子量对拉伸强度的影响，涉及多个概念关联和综合分析。解题步骤较为复杂，需要理解结晶度与拉伸强度的关系，以及分子量对性能的影响，并进行多角度分析论述。", "convertible": true, "correct_option": "The linear and isotactic material will have the higher tensile strength.", "choice_question": "For the following pair of polymers, which one has a higher tensile strength and why? Linear and isotactic poly(vinyl chloride) with a weight-average molecular weight of 100,000 g/mol; branched and atactic poly(vinyl chloride) having a weight-average molecular weight of 75,000 g/mol", "conversion_reason": "The original question asks for a comparison between two polymers based on their tensile strength, and the answer provides a clear, definitive choice with reasoning. This can be effectively converted into a multiple-choice question by presenting the correct option among plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The branched and atactic PVC due to its lower molecular weight allowing better chain packing", "B": "The linear and isotactic PVC because crystallinity increases with isotacticity", "C": "The branched and atactic PVC as branching increases entanglement density", "D": "Both have similar tensile strength as molecular weight differences compensate for structural variations" }, "correct_answer": "B", "explanation": "The correct answer is B because linear and isotactic PVC can form crystalline regions which significantly enhance tensile strength, despite its higher molecular weight. Option A is incorrect because while lower MW can improve packing, the atactic structure prevents crystallization. Option C is a trap as branching does increase entanglement but reduces crystallinity more significantly. Option D is incorrect because structural differences (tacticity and branching) dominate over the modest MW difference in determining mechanical properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1027, "question": "Analyze the characteristics of grain boundaries from the structural features of grain boundaries", "answer": "Structural features of grain boundaries: The atomic arrangement is relatively disordered and contains a large number of defects. Characteristics of grain boundaries: (3) Numerous defects such as dislocations and vacancies—high grain boundary diffusion rate. (6) Enrichment of trace elements and impurities.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析晶界的特性，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析晶界的结构特征及其特性，涉及对晶界原子排列无序性、缺陷类型（如位错和空位）以及微量元素富集等概念的综合理解和应用。虽然不涉及复杂计算，但需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题型中，该题目需要考生不仅理解晶界的基本结构特征（如原子排列无序和缺陷），还需要综合分析这些结构特征如何导致晶界的特性（如高扩散率和杂质富集）。这涉及多步骤的概念关联和综合分析，超出了简单的记忆或单一概念的应用，属于较高难度的选择题。", "convertible": true, "correct_option": "Numerous defects such as dislocations and vacancies—high grain boundary diffusion rate. Enrichment of trace elements and impurities.", "choice_question": "Which of the following best describes the characteristics of grain boundaries based on their structural features?", "conversion_reason": "The answer provided is a standard description of the characteristics of grain boundaries, which can be formatted into a multiple-choice question with the given answer as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Numerous defects such as dislocations and vacancies—high grain boundary diffusion rate. Enrichment of trace elements and impurities.", "B": "Perfect crystalline structure with no defects—low diffusion rate due to ordered atomic arrangement.", "C": "Amorphous structure with isotropic properties—uniform distribution of alloying elements.", "D": "High-angle boundaries acting as perfect mirrors for electron diffraction—no segregation of impurities." }, "correct_answer": "A", "explanation": "Correct answer A describes the actual characteristics of grain boundaries: they contain numerous defects that enhance diffusion, and tend to segregate impurities. Option B incorrectly describes grain boundaries as perfect crystals, exploiting the common misconception that boundaries maintain perfect order. Option C uses the amorphous structure analogy, a tempting but incorrect extrapolation from glassy materials. Option D combines a true statement about high-angle boundaries with a false claim about impurity segregation, creating a half-truth trap that requires careful boundary condition analysis.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2116, "question": "Point out the incorrect concept and correct it: In castings with uneven thickness, the thicker sections are prone to chill formation. Therefore, for such castings, more carbon and less silicon must be added.", "answer": "The thinner sections are prone to chill formation. More carbon and more silicon must be added.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出错误概念并进行纠正，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目不仅需要识别错误概念（基础记忆），还需要理解铸造过程中冷却速率与合金成分的关系（概念关联），并给出正确的合金成分调整方案（综合分析）。这涉及到多个知识点的关联应用和中等程度的推理分析。 | 难度: 在选择题中属于中等难度，需要理解铸件厚度与冷却速度的关系，并掌握碳和硅对铸铁凝固特性的影响。题目要求识别错误概念并选择正确表述，涉及多步概念关联和综合分析，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "The thinner sections are prone to chill formation. More carbon and more silicon must be added.", "choice_question": "Which of the following statements correctly identifies and corrects the misconception in castings with uneven thickness?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question by presenting the correct statement as one of the options. The answer provided is a standard correction that can be directly used as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The thinner sections are prone to chill formation. More carbon and more silicon must be added.", "B": "The thicker sections are prone to shrinkage porosity. More carbon and less silicon must be added.", "C": "The thinner sections are prone to hot tearing. Less carbon and more silicon must be added.", "D": "The thicker sections are prone to gas porosity. Less carbon and less silicon must be added." }, "correct_answer": "A", "explanation": "The correct answer is A because thinner sections cool faster, leading to chill formation, and increasing both carbon and silicon helps prevent this by promoting graphite formation. Option B incorrectly identifies the defect as shrinkage porosity in thicker sections and suggests less silicon, which would worsen the problem. Option C misidentifies the defect as hot tearing in thinner sections and suggests an incorrect alloy adjustment. Option D incorrectly identifies gas porosity in thicker sections and suggests reducing both carbon and silicon, which would be detrimental to the casting quality.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4425, "question": "Name two thermal properties of a liquid medium that will influence its quenching effectiveness.", "answer": "The two thermal properties of a liquid medium that influence its quenching effectiveness are thermal conductivity and heat capacity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举并解释液体介质的两个热性能，答案以文字解释的形式给出，没有选项或计算要求。 | 知识层次: 题目考查对液体介质热性能的基本概念记忆，仅需列举影响淬火效果的两个热性能参数，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目仅要求回忆并列举两个基本的热性能属性（热导率和热容量），属于基础概念记忆层次。题目不涉及解释或比较，解题步骤简单直接，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "thermal conductivity and heat capacity", "choice_question": "Which of the following are the two thermal properties of a liquid medium that influence its quenching effectiveness?", "conversion_reason": "The original short answer question asks for two specific thermal properties, which can be converted into a multiple-choice format by listing possible properties as options and identifying the correct pair.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermal conductivity and heat capacity", "B": "Viscosity and surface tension", "C": "Thermal diffusivity and boiling point", "D": "Specific heat and density" }, "correct_answer": "A", "explanation": "The correct answer is A because thermal conductivity determines how quickly heat is transferred from the material to the liquid, and heat capacity determines how much heat the liquid can absorb before its temperature rises significantly. Option B is incorrect because viscosity and surface tension affect fluid flow and wetting but not the fundamental heat transfer mechanism. Option C is a partial trap because thermal diffusivity combines conductivity and capacity, but boiling point is irrelevant for typical quenching temperatures. Option D is misleading because while specific heat is correct, density alone does not determine quenching effectiveness.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 529, "question": "1. Kaolinite belongs to the layered silicate structure, with one layer being (1) and another layer being (2).", "answer": "(1) silicon-oxygen tetrahedral layer; (2) aluminum-oxygen octahedral layer", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写特定术语（硅氧四面体层和铝氧八面体层），属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查高岭石（Kaolinite）的层状硅酸盐结构的基本组成，即硅氧四面体层和铝氧八面体层的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即高岭石的层状硅酸盐结构由硅氧四面体层和铝氧八面体层组成。无需复杂推理或概念间的联系分析，属于最基本的知识点复现。", "convertible": true, "correct_option": "silicon-oxygen tetrahedral layer and aluminum-oxygen octahedral layer", "choice_question": "Kaolinite belongs to the layered silicate structure, with one layer being silicon-oxygen tetrahedral layer and another layer being:", "conversion_reason": "The answer is a standard terminology and can be converted into a multiple-choice format by presenting the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "silicon-oxygen tetrahedral layer and aluminum-oxygen octahedral layer", "B": "silicon-oxygen tetrahedral layer and magnesium-oxygen octahedral layer", "C": "silicon-oxygen tetrahedral layer and silicon-oxygen octahedral layer", "D": "aluminum-oxygen tetrahedral layer and aluminum-oxygen octahedral layer" }, "correct_answer": "A", "explanation": "The correct answer is A because kaolinite's structure consists of alternating layers of silicon-oxygen tetrahedra and aluminum-oxygen octahedra. Option B is a cognitive bias trap, replacing aluminum with magnesium which occurs in other clay minerals. Option C exploits the 'first impression' fallacy by suggesting silicon can form octahedra. Option D is a professional intuition trap, creating a plausible-sounding but incorrect all-aluminum structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 622, "question": "From what is Fe3CIII precipitated", "answer": "Ferrite", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答Fe3CIII是从什么物质中沉淀出来的，答案\"Ferrite\"是一个简短的文字回答，不需要选择、判断或计算，符合简答题的特征。 | 知识层次: 题目考查Fe3CIII从何种相中析出的基础概念记忆，属于材料科学中相变的基本知识点，不需要复杂的推理或分析。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即Fe3CIII的析出来源这一简单定义性知识。题目仅需考生回忆并选择\"Ferrite\"这一正确答案，无需进行概念解释或复杂分析，属于最基本的选择题难度等级。", "convertible": true, "correct_option": "Ferrite", "choice_question": "From what is Fe3CIII precipitated?", "conversion_reason": "The answer is a standard term (Ferrite), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ferrite", "B": "Austenite", "C": "Cementite", "D": "Martensite" }, "correct_answer": "A", "explanation": "Fe3CIII precipitates from ferrite during the eutectoid reaction in steel. Option B (Austenite) is incorrect because Fe3C precipitates from austenite only at higher temperatures forming pearlite. Option C (Cementite) is a tempting choice due to the chemical similarity but is incorrect as it's the precipitate itself, not the parent phase. Option D (Martensite) exploits the common confusion between different steel microstructures, though martensite cannot precipitate Fe3C without tempering.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1674, "question": "After recrystallization is completed, grain growth can be divided into (17) _ grain growth and _ (18) grain growth.", "answer": "(17) normal; (18) abnormal", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个空白处的答案，需要根据知识进行简短的文字回答，而不是从选项中选择或进行判断、计算。 | 知识层次: 题目考查的是再结晶完成后晶粒生长的两种基本类型（正常晶粒生长和异常晶粒生长）的记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即晶粒生长的两种类型（正常和异常）。题目直接给出定义性知识，无需解释或复杂分析，属于最基本的知识点掌握要求。", "convertible": true, "correct_option": "normal; abnormal", "choice_question": "After recrystallization is completed, grain growth can be divided into:", "conversion_reason": "The short answer question can be converted into a multiple-choice question as the answer consists of standard terms (normal and abnormal grain growth). The question can be rephrased to fit a multiple-choice format by presenting the options separately.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "normal; abnormal", "B": "primary; secondary", "C": "isotropic; anisotropic", "D": "continuous; discontinuous" }, "correct_answer": "A", "explanation": "正确答案A（normal; abnormal）是材料科学中描述再结晶后晶粒生长的标准术语。干扰项B（primary; secondary）利用了相变术语的认知偏差；干扰项C（isotropic; anisotropic）针对晶体学特性的直觉陷阱；干扰项D（continuous; discontinuous）则模仿了其他材料过程的分类方式。这些干扰项都利用了材料科学中常见但在此情境下不正确的概念关联。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1495, "question": "A single crystal (BCC) rod is stretched along the rod axis [213] direction to undergo plastic deformation. Given that the slip plane of the single crystal is {110}, determine the double slip system.", "answer": "The double slip system is (011)[111]－(011)[111].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来确定双滑移系统，答案是一个具体的滑移系统组合，而不是简单的选择、判断或计算。 | 知识层次: 题目要求确定双滑移系统，需要理解BCC晶体结构、滑移面和滑移方向的关系，并进行综合分析。虽然不涉及复杂的计算，但需要将多个概念关联起来，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目要求考生理解BCC晶体结构、滑移面和滑移方向的概念，并能够将这些概念关联起来。其次，题目涉及多步计算，包括确定滑移系统以及判断双滑移系统，这需要考生具备较强的综合分析能力。此外，题目还要求考生能够将理论知识与实际应用相结合，进一步增加了难度。因此，在选择题型内，该题目属于多角度分析论述的难度等级。", "convertible": true, "correct_option": "(011)[111]－(011)[111]", "choice_question": "A single crystal (BCC) rod is stretched along the rod axis [213] direction to undergo plastic deformation. Given that the slip plane of the single crystal is {110}, which of the following is the double slip system?", "conversion_reason": "The answer is a standard terminology or concept, which can be presented as a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(011)[111]－(011)[111]", "B": "(101)[111]－(101)[111]", "C": "(110)[111]－(110)[111]", "D": "(011)[111]－(101)[111]" }, "correct_answer": "A", "explanation": "The correct answer A represents the double slip system where both slip directions are parallel to the [111] direction on the (011) plane, which is the most energetically favorable configuration for BCC crystals under [213] tension. Option B uses the wrong slip plane indices (101) which would require higher critical resolved shear stress. Option C incorrectly uses the (110) plane which is not the primary slip plane for BCC. Option D mixes different slip planes which would not produce symmetrical deformation required for double slip. Advanced AIs might incorrectly choose D due to its partial correctness in containing the correct slip direction.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3145, "question": "The volume change rate during the γ-Fe→α-Fe transformation (given the lattice constant of γ-Fe α=0.3633nm, and the lattice constant of α-Fe α=0.2892nm)", "answer": "The volume change rate ΔV=(Vα-Vγ)/Vγ=(0.2892³×1/2-0.3633³×1/4)/(0.3633³×1/4)≈0.886", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的晶格常数计算γ-Fe→α-Fe相变过程中的体积变化率，涉及数值计算和公式应用，答案以数值结果呈现。 | 知识层次: 题目涉及多步计算和概念关联，需要理解晶体结构、相变过程中的体积变化计算，并正确应用公式进行数值计算。虽然不涉及复杂的推理分析或机理解释，但需要综合运用多个知识点进行计算。 | 难度: 在选择题中属于中等偏上难度，需要理解γ-Fe和α-Fe的晶体结构差异（面心立方和体心立方），掌握晶格常数与体积的关系，并能正确应用体积计算公式。题目涉及多步计算（包括立方运算和分数运算）和概念关联（晶体结构转变与体积变化），但计算过程相对明确，不需要处理复杂变量或高级数学工具。", "convertible": true, "correct_option": "0.886", "choice_question": "The volume change rate during the γ-Fe→α-Fe transformation (given the lattice constant of γ-Fe α=0.3633nm, and the lattice constant of α-Fe α=0.2892nm) is approximately:", "conversion_reason": "The calculation question has a specific numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.886", "B": "1.128", "C": "0.796", "D": "1.254" }, "correct_answer": "A", "explanation": "The correct answer is calculated by comparing the unit cell volumes of γ-Fe (FCC) and α-Fe (BCC). For FCC, there are 4 atoms per unit cell with volume a³, while BCC has 2 atoms per unit cell with volume a³. The volume change rate is (2*(0.2892)³)/(4*(0.3633)³) ≈ 0.886. Option B is the reciprocal of the correct answer, exploiting the common mistake of inverting the ratio. Option C is derived by incorrectly assuming simple cubic packing for both phases. Option D comes from miscalculating the coordination number effect without considering the atomic packing factors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 712, "question": "What are the process characteristics of secondary recrystallization", "answer": "It is an abnormal growth process where a few large grains grow at the expense of fine grains. It is the abnormal growth of individual grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释二次再结晶的过程特征，答案提供了详细的文字解释和论述，符合简答题的特点。 | 知识层次: 题目考查对二次再结晶过程特性的基本概念记忆和理解，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生对二次再结晶的过程特征有较为清晰的理解，能够区分正常晶粒生长和异常晶粒生长的差异。正确选项不仅描述了二次再结晶的基本特征（异常生长过程），还进一步解释了其具体表现（少数大晶粒消耗小晶粒）。这要求考生不仅记住定义，还要理解其背后的原理，属于概念解释和描述的层次。", "convertible": true, "correct_option": "It is an abnormal growth process where a few large grains grow at the expense of fine grains. It is the abnormal growth of individual grains.", "choice_question": "Which of the following best describes the process characteristics of secondary recrystallization?", "conversion_reason": "The answer is a standard description of a concept, which can be converted into a multiple-choice question format by providing the correct option among possible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It is an abnormal growth process where a few large grains grow at the expense of fine grains", "B": "It is a uniform grain growth process driven by reduction of total grain boundary energy", "C": "It involves simultaneous nucleation and growth of new grains with random orientations", "D": "It is a stress-induced process where grains rotate to form preferred orientations" }, "correct_answer": "A", "explanation": "The correct answer A describes the key characteristic of secondary recrystallization as abnormal grain growth where select grains grow disproportionately. Option B is incorrect because it describes normal grain growth, not abnormal growth. Option C is a trap as it describes primary recrystallization, exploiting confusion between similar terms. Option D is misleading as it describes texture development mechanisms rather than abnormal grain growth.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2029, "question": "A common polymer has C2H2Cl2 as its monomer, with an average molecular weight of 60000u (using the relative atomic masses of the elements as Ar(C)=12, Ar(H)=1, Ar(Cl)=35.5). Calculate the mass of the monomer.", "answer": "The mass of the monomer is 12×2 + 1×2 + 35.5×2 = 97u/mol", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算单体的质量），并给出了具体的原子质量和计算公式，答案也是通过计算得出的具体数值。 | 知识层次: 题目仅需应用基本化学公式进行简单的分子量计算，无需多步推理或综合分析，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目仅需要直接套用基本公式进行简单的原子质量相加计算，无需复杂的推理或多步骤操作。属于单一公式直接计算的难度等级。", "convertible": true, "correct_option": "97u/mol", "choice_question": "A common polymer has C2H2Cl2 as its monomer, with an average molecular weight of 60000u (using the relative atomic masses of the elements as Ar(C)=12, Ar(H)=1, Ar(Cl)=35.5). What is the mass of the monomer?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "97u/mol", "B": "194u/mol", "C": "48.5u/mol", "D": "60000u/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (97u/mol) calculated as (2×12) + (2×1) + (2×35.5) = 97u/mol. Option B (194u/mol) is a cognitive bias trap - doubling the correct value to trick those who might think the monomer is a dimer. Option C (48.5u/mol) exploits unit confusion by halving the correct value. Option D (60000u/mol) is a direct distraction using the polymer's molecular weight instead of the monomer's.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1289, "question": "Dynamic recovery and dynamic recrystallization refer to deformation at high temperatures, where (18) occurs simultaneously during the deformation process.", "answer": "(18) work hardening and softening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个短语或短句来补全句子，而不是从多个选项中选择或进行判断。答案需要简要解释或描述概念，符合简答题的特征。 | 知识层次: 题目考查动态回复和动态再结晶的基本概念，需要记忆和理解这些术语的定义及其在高温度变形过程中的作用。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即动态恢复和动态再结晶的定义。正确选项直接给出了\"work hardening and softening\"这一基本概念，无需进行复杂的分析或推理。题目属于基础概念记忆层次，符合等级1的难度标准。", "convertible": true, "correct_option": "work hardening and softening", "choice_question": "Dynamic recovery and dynamic recrystallization refer to deformation at high temperatures, where (18) occurs simultaneously during the deformation process. Which of the following correctly fills in the blank (18)?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "work hardening and softening", "B": "dislocation multiplication and annihilation", "C": "grain growth and refinement", "D": "phase transformation and precipitation" }, "correct_answer": "A", "explanation": "正确答案A正确描述了高温变形过程中同时发生的加工硬化和动态回复/再结晶导致的软化。干扰项B利用位错动态的直觉判断，但忽略了这是微观机制而非宏观表现；C利用晶粒尺寸变化的常见认知偏差，但混淆了静态和动态过程；D通过引入相变概念制造专业直觉陷阱，虽然相变可能发生但不属于动态回复/再结晶的本质特征。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4134, "question": "If you were to locally heat identical geometry plates of the materials listed below with the same heat source, which would increase in temperature the fastest? (a) Polystyrene (b) Aluminum (c) Copper (d) Gold (e) Borosilicate Glass", "answer": "In this scenario, the material with the highest thermal conductivity will conduct heat the fastest. Therefore this material will absorb heat and increase in temperature the fastest. In this case, copper has the highest thermal conductivity.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查对材料热导率这一基本概念的简单记忆和理解，只需知道不同材料的热导率差异即可直接选择正确答案，无需复杂分析或计算。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要理解热导率的基本概念，但只需比较几种常见材料的热导率即可得出答案。题目提供了明确的材料选项，且铜的热导率在选项中最高是较为基础的知识点，不需要复杂的分析或计算步骤。因此，该题目属于概念理解和简单辨析的层次。", "convertible": true, "correct_option": "Copper", "choice_question": "If you were to locally heat identical geometry plates of the materials listed below with the same heat source, which would increase in temperature the fastest?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer (Copper) based on the explanation provided. Therefore, it can be directly converted to a single-choice question format without any modifications to the question itself.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polycrystalline diamond (thermal conductivity: 2000 W/mK)", "B": "Single-crystal graphene (in-plane thermal conductivity: 5000 W/mK)", "C": "Electrolytic copper (thermal conductivity: 400 W/mK)", "D": "Pyrolytic graphite (through-plane thermal conductivity: 10 W/mK)" }, "correct_answer": "C", "explanation": "While graphene and diamond have higher nominal thermal conductivities, the correct answer is copper because: 1) Polycrystalline diamond's actual thermal conductivity is significantly lower than theoretical values due to grain boundary scattering (cognitive bias trap). 2) Graphene's ultra-high conductivity only applies to in-plane directions in perfect single crystals (dimensionality trap). 3) Pyrolytic graphite's through-plane conductivity is poor (anisotropy trap). Copper's consistent isotropic conductivity and practical heat spreading capability make it the fastest temperature riser under localized heating.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2634, "question": "The percentage of ionic character in the bonding between elements A and B can be approximately expressed by the following formula: IC(%)=[1-e^(-0.25(x_A-x_B)^2)]×100, where x_A and x_B are the electronegativity values of elements A and B, respectively. Given that the electronegativities of In and Sb are 1.7 and 1.9, respectively, calculate the IC(%) for InSb.", "answer": "For InSb: IC(%)=[1-e^(-0.25)(1.9-1.7)^2]×100=1.0%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求使用给定的公式进行数值计算，最终得出一个具体的百分比数值。解答过程涉及代入已知的电子亲和力值并进行数学运算，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，只需将给定的电负性值代入公式进行计算即可，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用给定的公式进行简单计算，无需额外的概念理解或复杂的解题步骤。题目提供了所有必要的信息（电负性值和公式），学生只需将数值代入公式并完成基本的数学运算即可得出答案。因此，该题目在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "1.0%", "choice_question": "The percentage of ionic character in the bonding between In and Sb can be approximately expressed by the following formula: IC(%)=[1-e^(-0.25(x_A-x_B)^2)]×100, where x_A and x_B are the electronegativity values of elements A and B, respectively. Given that the electronegativities of In and Sb are 1.7 and 1.9, respectively, the IC(%) for InSb is:", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.0%", "B": "4.0%", "C": "0.1%", "D": "10.0%" }, "correct_answer": "A", "explanation": "The correct answer is A (1.0%) calculated using the given formula IC(%)=[1-e^(-0.25(1.9-1.7)^2)]×100. Option B (4.0%) exploits the cognitive bias of overestimating ionic character in III-V compounds. Option C (0.1%) is designed as a common calculation error when misapplying the exponent. Option D (10.0%) is a professional intuition trap, mimicking values seen in more ionic II-VI compounds.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 605, "question": "When a disordered solid solution transforms into an ordered solid solution, the general trend in the change of alloy properties is: plasticity", "answer": "decreases", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释无序固溶体转变为有序固溶体时合金塑性变化的趋势，需要文字解释和论述，答案\"decreases\"是对趋势的简要描述，符合简答题的特征。 | 知识层次: 题目考查对有序固溶体转变过程中塑性变化这一基本概念的记忆和理解，属于基础概念记忆范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，此题仅考察对基础概念的简单记忆（有序固溶体转变对塑性影响的基本规律），不需要解释或分析过程，属于最基础的定义性知识考查。", "convertible": true, "correct_option": "decreases", "choice_question": "When a disordered solid solution transforms into an ordered solid solution, the general trend in the change of alloy properties is:", "conversion_reason": "The answer is a standard term that can be presented as a single correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Decreases", "B": "Increases", "C": "Remains constant", "D": "First increases then decreases" }, "correct_answer": "A", "explanation": "The correct answer is A because ordering reduces dislocation mobility, decreasing plasticity. Option B exploits the common misconception that ordering improves all mechanical properties. Option C targets oversimplified thinking about phase transformations. Option D creates complexity by suggesting a non-monotonic trend, which is plausible for some properties but not plasticity in this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4806, "question": "What is the maximum carbon content possible for a plain carbon steel that must have an impact energy of at least 200 Jat -50^{\\circ} C ?", "answer": "the maximum carbon concentration is 0.11% C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算最大碳含量，需要基于材料科学的知识和公式进行数值计算，最终给出具体的数值答案（0.11% C）。 | 知识层次: 题目需要多步计算和概念关联，涉及碳含量与冲击韧性的关系，并需要综合分析材料性能数据来确定最大碳含量。 | 难度: 在选择题中属于中等偏上难度，需要综合理解碳钢的碳含量与冲击韧性的关系，并结合温度影响进行多步分析判断。题目要求考生不仅掌握材料性能的基本概念，还需要能够将不同知识点关联起来进行综合分析，才能正确选择最大碳含量限制。", "convertible": true, "correct_option": "0.11% C", "choice_question": "What is the maximum carbon content possible for a plain carbon steel that must have an impact energy of at least 200 J at -50°C?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.11% C", "B": "0.25% C", "C": "0.35% C", "D": "0.50% C" }, "correct_answer": "A", "explanation": "The correct answer is 0.11% C because higher carbon content significantly reduces impact toughness, especially at low temperatures. Option B (0.25% C) exploits the cognitive bias that moderate carbon content might balance strength and toughness. Option C (0.35% C) is a professional intuition trap, as this is a common structural steel composition but fails the impact requirement. Option D (0.50% C) is a multi-level verification trap, using a real high-carbon steel value but ignoring the drastic toughness reduction.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 598, "question": "The close-packed plane of FCC structure is", "answer": "{111}", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答FCC结构的密排面，答案是一个特定的晶面指数{111}，这属于需要特定知识点的简短回答，不需要计算或选择，也不涉及判断对错 | 知识层次: 题目考查对FCC结构密排面的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，此题属于非常基础的难度等级。题目仅考察对FCC结构密排面的记忆性知识，不需要任何解释、分析或推导过程。学生只需记住FCC的密排面是{111}晶面这一基本事实即可作答，属于最基础的定义性知识考察。在选择题型内，这类仅需记忆单一知识点的题目是最简单的类型。", "convertible": true, "correct_option": "{111}", "choice_question": "The close-packed plane of FCC structure is:", "conversion_reason": "The answer is a standard term in crystallography, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "{111}", "B": "{110}", "C": "{100}", "D": "{112}" }, "correct_answer": "A", "explanation": "The {111} plane is the close-packed plane in FCC structures due to its highest atomic packing density. Option B ({110}) is a common confusion as it appears densely packed in 2D projections but has lower atomic density. Option C ({100}) exploits the misconception that cubic faces might be most packed. Option D ({112}) is a real FCC plane but with significantly lower packing density, designed to trap those recalling less common indices.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 34, "question": "According to the rules of ionic compound formation, when all octahedral interstitial sites are filled, what valence cations should be inserted in the interstitial sites? Please provide examples.", "answer": "The ratio of cation to anion valences should be 1:1, such as NaCl.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释离子化合物形成规则，并提供例子，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对离子化合物形成规则的基本应用，需要理解八面体间隙填充的价态规则，并给出具体例子。虽然涉及一定的概念理解，但主要是直接应用基本原理，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单应用难度。题目直接考察对离子化合物形成规则的基本理解，只需套用已知的1:1价态比例规则即可选出正确答案。解题步骤简单明确，不需要复杂分析或计算，符合选择题型中对基本知识点直接应用的考查要求。", "convertible": true, "correct_option": "The ratio of cation to anion valences should be 1:1, such as NaCl.", "choice_question": "According to the rules of ionic compound formation, when all octahedral interstitial sites are filled, what valence cations should be inserted in the interstitial sites?", "conversion_reason": "The answer is a standard concept with a clear example, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ratio of cation to anion valences should be 1:1, such as NaCl", "B": "The cation valence should be twice the anion valence, such as CaF2", "C": "The cation valence should equal the coordination number, such as ZnS", "D": "The cation valence should balance the total anionic charge, such as Al2O3" }, "correct_answer": "A", "explanation": "The correct answer is A because when all octahedral sites are filled in a close-packed anion array, the stoichiometry requires a 1:1 cation-to-anion valence ratio to maintain charge neutrality, as exemplified by NaCl. Option B is a cognitive bias trap, applying the correct rule for tetrahedral sites (fluorite structure) to octahedral sites. Option C exploits professional intuition by suggesting coordination number determines valence, which is only true for certain structures like zinc blende. Option D is a multi-level verification trap, presenting a generally correct principle but failing to account for the specific geometric constraints of octahedral site filling.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4396, "question": "What is the principal difference between wrought and cast alloys?", "answer": "The principal difference between wrought and cast alloys is as follows: wrought alloys are ductile enough so as to be hot or cold worked during fabrication, whereas cast alloys are brittle to the degree that shaping by deformation is not possible and they must be fabricated by casting.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述锻造合金和铸造合金的主要区别，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对锻造合金和铸造合金基本概念的记忆和理解，属于定义和分类的基础知识范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆（定义和分类），但需要考生理解并区分两种合金类型的关键特性（可锻性和铸造性）。正确选项提供了明确的对比描述，但需要考生掌握\"wrought\"和\"cast\"这两个专业术语的含义以及它们在加工性能上的差异。这比单纯记忆单个定义（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Wrought alloys are ductile enough to be hot or cold worked during fabrication, whereas cast alloys are brittle and must be fabricated by casting.", "choice_question": "What is the principal difference between wrought and cast alloys?", "conversion_reason": "The answer is a standard explanation that can be rephrased into a clear and concise option for a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Wrought alloys have higher ductility allowing mechanical working, while cast alloys require liquid-state processing", "B": "Wrought alloys contain higher carbon content which improves their forgeability compared to cast alloys", "C": "Cast alloys develop directional grain structures during solidification, unlike wrought alloys", "D": "Wrought alloys always exhibit superior corrosion resistance due to their thermomechanical processing" }, "correct_answer": "A", "explanation": "Correct answer A precisely captures the fundamental difference in fabrication methods. Option B uses carbon content as a misleading factor (cognitive bias). Option C describes a true but secondary microstructural difference (intuition trap). Option D introduces an unrelated property correlation (multi-level trap) that doesn't define the principal difference.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2381, "question": "MgO dissolves into Al2O3 to form a solid solution. Assuming Mg2+ replaces Al3+, write the reaction equation using Kroger-Vink notation.", "answer": "2MgO forms 2MgAl' + V..O + 2OOX through Al2O3", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求使用Kroger-Vink符号写出反应方程式，需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目要求使用Kroger-Vink符号表示固溶体形成反应，这需要理解缺陷化学的基本原理和符号规则，并能够将其应用于具体反应中。虽然不涉及复杂的计算或综合分析，但需要将多个概念（如离子取代、缺陷形成）关联起来，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目要求使用Kroger-Vink符号表示反应方程，这需要学生对缺陷化学符号系统有深入理解。其次，题目涉及离子替代反应，需要学生掌握电荷平衡和缺陷补偿的概念。此外，解题过程需要多步推理：1) 识别Mg2+替代Al3+产生的缺陷类型；2) 确定电荷补偿机制；3) 正确应用Kroger-Vink符号表示所有缺陷和晶格位置。这种综合分析能力和多概念关联的要求，使该题在选择题型中属于较难水平。", "convertible": true, "correct_option": "2MgO forms 2MgAl' + V..O + 2OOX through Al2O3", "choice_question": "MgO dissolves into Al2O3 to form a solid solution. Assuming Mg2+ replaces Al3+, which of the following is the correct reaction equation using Kroger-Vink notation?", "conversion_reason": "The answer is a standard and specific reaction equation, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2MgO → 2MgAl' + V..O + 2OOX", "B": "MgO → MgAl' + VO•• + OOX", "C": "3MgO → 3MgAl' + V..O + 3OOX", "D": "MgO + Al2O3 → MgAl' + AlO• + OOX" }, "correct_answer": "A", "explanation": "The correct answer A balances both mass and charge while maintaining the correct stoichiometry for Mg2+ replacing Al3+. Option B incorrectly uses VO•• (doubly charged oxygen vacancy) which would create charge imbalance. Option C violates stoichiometry by introducing an extra MgO. Option D incorrectly suggests AlO• formation which doesn't occur in this substitution mechanism. The key difficulty lies in simultaneously tracking: 1) correct defect notation, 2) charge balance, and 3) stoichiometric coefficients - a combination that often trips up even advanced AI systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4835, "question": "Briefly state what is meant by the mobility of a free electron.", "answer": "The mobility is the proportionality constant between the drift velocity and the electric field. It is also a measure of the frequency of scattering events (and is inversely proportional to the frequency of scattering).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要解释自由电子迁移率的概念，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目考查对自由电子迁移率这一基本概念的定义和理解，属于基础概念的记忆性知识，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目要求考生不仅记忆自由电子迁移率的基本定义，还需要理解其与漂移速度和电场之间的关系，以及散射事件频率的影响。这超出了简单的定义记忆（等级1），但尚未达到需要阐述复杂概念体系的程度（等级3）。因此属于概念解释和描述的中等难度等级。", "convertible": true, "correct_option": "The mobility is the proportionality constant between the drift velocity and the electric field. It is also a measure of the frequency of scattering events (and is inversely proportional to the frequency of scattering).", "choice_question": "Which of the following best describes the mobility of a free electron?", "conversion_reason": "The answer is a standard definition and can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The proportionality constant between drift velocity and applied electric field, inversely related to scattering frequency", "B": "The ratio of electron velocity to atomic lattice vibration frequency in a perfect crystal", "C": "The maximum attainable velocity of an electron in a material before dielectric breakdown occurs", "D": "The quantum mechanical probability of an electron transitioning between valence and conduction bands" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines electron mobility as the drift velocity per unit electric field while highlighting its inverse relationship with scattering. Option B exploits confusion with phonon-electron coupling in perfect crystals. Option C creates a false intuition about velocity limits by mixing concepts from dielectric theory. Option D strategically misapplies quantum mechanical transition probabilities that are unrelated to mobility calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4917, "question": "For the following pair of materials, decide which has the larger thermal conductivity. Justify your choice. Atactic polypropylene (Mw=10^6 g/mol); isotactic polypropylene (Mw=10^5 g/mol)", "answer": "The isotactic polypropylene will have a larger thermal conductivity than the atactic polypropylene because isotactic polymers have higher degrees of crystallinity. The influence of crystallinity on conductivity is explained in part (c).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的导热性能并给出理由，需要文字解释和论述，而不是简单的选择或判断。答案中提供了详细的解释，符合简答题的特征。 | 知识层次: 题目要求比较两种聚合物的热导率，并解释原因。这需要理解聚合物结构（等规和无规）对结晶度的影响，以及结晶度如何影响热导率。虽然涉及多个概念，但主要是概念关联和综合分析，不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解聚合物立构规整性（isotactic vs atactic）对结晶度的影响，以及结晶度与热导率的关系这两个关键概念，并进行比较分析。虽然不涉及复杂计算，但需要综合应用材料结构-性能关系的知识来做出判断。", "convertible": true, "correct_option": "The isotactic polypropylene will have a larger thermal conductivity than the atactic polypropylene because isotactic polymers have higher degrees of crystallinity.", "choice_question": "For the following pair of materials, which has the larger thermal conductivity? Atactic polypropylene (Mw=10^6 g/mol); isotactic polypropylene (Mw=10^5 g/mol)", "conversion_reason": "The original question asks for a comparison between two materials with a clear justification provided in the answer. This can be converted into a multiple-choice question by presenting the answer as one of the options and possibly adding plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Isotactic polypropylene due to higher crystallinity", "B": "Atactic polypropylene due to higher molecular weight", "C": "Both have equal thermal conductivity as they are the same polymer", "D": "Atactic polypropylene due to more efficient phonon scattering" }, "correct_answer": "A", "explanation": "The correct answer is A because isotactic polypropylene has higher crystallinity which enhances thermal conductivity through more efficient phonon transport. Option B is a molecular weight trap - while higher Mw affects mechanical properties, it doesn't directly increase thermal conductivity. Option C is a polymer identity fallacy - tacticity creates fundamentally different microstructures. Option D reverses the phonon scattering mechanism - atactic's amorphous regions actually hinder thermal transport.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4759, "question": "Compute the modulus of elasticity for the nonporous material given that the modulus of elasticity for spinel (MgAl2O4) having 5 vol% porosity is 240 GPa (35 x 10^6 psi).", "answer": "the modulus of elasticity for the nonporous material is 265 gpa (38.6 x 10^6 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解非多孔材料的弹性模量，答案是一个具体的数值计算结果。 | 知识层次: 题目需要应用多孔材料弹性模量的计算公式，进行多步计算和概念关联，涉及孔隙率对材料性能的影响分析，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解孔隙率对弹性模量的影响，并应用相关公式进行多步计算。题目要求从已知多孔材料的弹性模量反推无孔隙材料的弹性模量，涉及概念关联和综合分析能力。虽然题目给出了正确选项，但解题过程需要掌握材料科学中孔隙率与力学性能的关系，并正确应用修正公式进行计算。", "convertible": true, "correct_option": "265 GPa (38.6 x 10^6 psi)", "choice_question": "Given that the modulus of elasticity for spinel (MgAl2O4) having 5 vol% porosity is 240 GPa (35 x 10^6 psi), what is the modulus of elasticity for the nonporous material?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "265 GPa (38.6 x 10^6 psi)", "B": "252 GPa (36.5 x 10^6 psi)", "C": "240 GPa (35 x 10^6 psi)", "D": "228 GPa (33 x 10^6 psi)" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the porosity correction formula E = E0(1 - 1.9P + 0.9P^2), where E0 is the nonporous modulus and P is porosity. Solving 240 = E0(1 - 1.9*0.05 + 0.9*0.0025) gives E0 = 265 GPa. Option B is a linear approximation trap (240/0.95). Option C is the porous value itself, exploiting failure to recognize the need for correction. Option D reverses the porosity effect, a common sign error in calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1676, "question": "Compare the number of valence electrons in CaO and MgO, and determine whether CaO-MgO meets the electron concentration condition for forming a solid solution.", "answer": "CaO and MgO have the same number of valence electrons, meeting the electron concentration condition for forming a solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较CaO和MgO的价电子数，并判断是否满足形成固溶体的电子浓度条件，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要比较CaO和MgO的价电子数，并判断是否符合形成固溶体的电子浓度条件。这涉及基本概念的应用（价电子数和固溶体形成条件），但不需要复杂的计算或深入的分析，属于直接套用基本原理的简单应用。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需要基本公式应用和简单计算。题目直接比较CaO和MgO的价电子数，并套用固溶体形成的电子浓度条件，解题步骤简单明了，无需复杂分析或深入理解多个概念。", "convertible": true, "correct_option": "CaO and MgO have the same number of valence electrons, meeting the electron concentration condition for forming a solid solution.", "choice_question": "Compare the number of valence electrons in CaO and MgO, and determine whether CaO-MgO meets the electron concentration condition for forming a solid solution.", "conversion_reason": "The answer is a standard statement that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "CaO and MgO have the same number of valence electrons, meeting the electron concentration condition for forming a solid solution", "B": "CaO has more valence electrons than MgO, but the difference is small enough to allow solid solution formation", "C": "MgO has more valence electrons than CaO, preventing solid solution formation due to electron concentration mismatch", "D": "While both have the same number of valence electrons, the large size difference between Ca and Mg prevents solid solution formation" }, "correct_answer": "A", "explanation": "The correct answer is A because both CaO and MgO have the same number of valence electrons (2 from the metal + 6 from oxygen = 8 total), satisfying the electron concentration condition for solid solution formation. Option B is incorrect because they actually have the same number of valence electrons, not just a small difference. Option C is wrong for the same reason, plus it incorrectly states that electron concentration mismatch would prevent solid solution formation. Option D contains a half-truth (same valence electrons) but incorrectly concludes that size difference prevents solid solution formation, when in reality size difference affects solubility limits but doesn't prevent solid solution formation entirely.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 182, "question": "Given the surface tension is 0.9 J/m², calculate the additional pressure for curved surfaces with radii of curvature of 0.5 μm and 5 μm?", "answer": "According to the Laplace formula: ΔP=γ(1/r1+1/r2), the calculated ΔP=0.9×(1/0.5+1/5)=1.98×10^6 Pa", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算并应用公式（Laplace公式）来求解附加压力，答案也是通过计算得出的具体数值。 | 知识层次: 题目主要考查对Laplace公式的直接应用和简单计算，无需多步推理或综合分析，属于基本公式的直接套用。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解Laplace公式并正确代入数值，但解题步骤较为直接，仅涉及单一公式的套用和简单计算，无需多个公式组合或复杂分析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "1.98×10^6 Pa", "choice_question": "Given the surface tension is 0.9 J/m², what is the additional pressure for curved surfaces with radii of curvature of 0.5 μm and 5 μm?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.98×10^6 Pa", "B": "3.6×10^3 Pa", "C": "1.8×10^6 Pa", "D": "9.0×10^5 Pa" }, "correct_answer": "A", "explanation": "正确答案A使用Young-Laplace方程ΔP=2γ/R正确计算了0.5μm半径的附加压力。B项错误地将表面张力值直接作为压力结果，忽略了曲率半径的影响。C项是5μm半径的计算结果，但题目要求的是0.5μm的情况。D项只计算了单侧曲率的压力，忽略了曲面双面性的2倍系数。干扰项设计利用了单位换算陷阱(B)、半径混淆(C)和方程理解不完整(D)等常见错误模式。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4067, "question": "[b] The density of copper is closer to that of aluminum than it is to iron.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（铜的密度更接近铝而不是铁），并要求判断其正确性（答案为F，即错误）。这符合判断题的特征，即判断陈述的对错。 | 知识层次: 题目考查对铜、铝和铁密度的基础概念记忆，属于定义和分类的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念正误判断，仅需记忆铜、铝和铁的密度关系即可做出正确判断。题目不涉及复杂概念或分析过程，属于最简单的难度等级。", "convertible": true, "correct_option": "F", "choice_question": "[b] The density of copper is closer to that of aluminum than it is to iron.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit higher thermal conductivity than all metallic materials under standard conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because while many ceramics have lower thermal conductivity than metals, there are exceptions like diamond (a ceramic) which has extremely high thermal conductivity, and some specialized metallic alloys with very low conductivity. The absolute term 'all' makes this statement incorrect. This tests understanding of material property ranges and the danger of absolute statements in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1, "question": "What are the parameters used to quantitatively describe crystal structures?", "answer": "Unit cell parameters.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述晶体结构的定量描述参数，答案是一个概念性的简短回答而非计算或选择 | 知识层次: 题目考查对晶体结构定量描述参数的基本概念记忆，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察对晶体结构基本参数的定义记忆，属于最基础的概念性知识。学生只需识别\"Unit cell parameters\"这一标准术语即可作答，无需任何解释或分析步骤，因此属于难度等级1。", "convertible": true, "correct_option": "Unit cell parameters", "choice_question": "Which of the following are the parameters used to quantitatively describe crystal structures?", "conversion_reason": "The answer is a standard term that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Unit cell parameters (a, b, c, α, β, γ)", "B": "Miller indices (hkl)", "C": "Burgers vector magnitude and direction", "D": "Elastic compliance tensor components" }, "correct_answer": "A", "explanation": "Unit cell parameters are the fundamental quantitative descriptors of crystal structures, defining lattice dimensions and angles. Miller indices (B) describe crystallographic planes, not the structure itself. Burgers vector (C) characterizes dislocations, not perfect crystal structures. Elastic compliance tensor (D) describes mechanical response, not atomic arrangement. The trap lies in the fact that all options are valid materials science parameters, requiring precise understanding of what constitutes structural description versus derived properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2931, "question": "Two parallel screw dislocations, when their Burgers vectors are in the same direction, the interaction force between them is (A) zero (B) repulsive (C) attractive", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（A、B、C）中选择关于两个平行螺位错相互作用力的正确答案 | 知识层次: 题目考查对平行螺型位错相互作用力的基本概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解螺位错相互作用的基本原理，并能够区分不同Burgers向量方向下的相互作用力类型（排斥或吸引）。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或比较（等级3）。", "convertible": true, "correct_option": "B", "choice_question": "Two parallel screw dislocations, when their Burgers vectors are in the same direction, the interaction force between them is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The force is zero because screw dislocations do not interact elastically", "B": "Repulsive, as the strain fields of like-signed dislocations overlap", "C": "Attractive, due to the reduction in elastic strain energy", "D": "Depends on the crystal structure's Poisson ratio" }, "correct_answer": "B", "explanation": "The correct answer is B because parallel screw dislocations with parallel Burgers vectors create overlapping strain fields that generate a repulsive force. Option A is a cognitive bias trap exploiting the misconception that screw dislocations don't interact. Option C reverses the actual energy minimization principle. Option D introduces a valid but irrelevant parameter (Poisson ratio only affects edge dislocation interactions).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2791, "question": "Calculate the root mean square displacement of the total migration of carbon atoms $\\\\sqrt{\\\\overline{R_{n}^{2}}}$, given the jump frequency of carbon atoms as $\\\\Gamma=1.7\\\\times10^{9}/\\\\mathrm{s}$, the jump distance as $2.53\\\\times10^{-10}\\\\mathrm{m}$, and the time as $4\\\\mathrm{h}$.", "answer": "$\\\\sqrt{\\\\overline{R_{n}^{2}}}=\\\\sqrt{n}\\\\cdot r=\\\\sqrt{1.7\\\\times10^{9}\\\\times4\\\\times3600}\\\\times2.53\\\\times10^{-10}=1.25\\\\times10^{-3}\\\\mathrm{m}\\\\approx1.3\\\\mathrm{mm}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算，应用给定的公式和参数来求解碳原子的均方根位移。答案是通过具体的数学计算得出的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括时间单位转换、根均方位移公式的应用以及数值计算，涉及对扩散理论的理解和公式的综合运用，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散理论中的均方位移概念，并正确应用公式进行多步计算。题目涉及单位换算（小时转秒）、平方根运算以及科学计数法的处理，虽然计算步骤明确但容易在细节上出错。相比单纯的概念题或单步计算题更具挑战性，但尚未达到需要处理复杂变量或高级数学工具的等级4难度。", "convertible": true, "correct_option": "$1.3\\mathrm{mm}$", "choice_question": "Calculate the root mean square displacement of the total migration of carbon atoms $\\sqrt{\\overline{R_{n}^{2}}}$, given the jump frequency of carbon atoms as $\\Gamma=1.7\\times10^{9}/\\mathrm{s}$, the jump distance as $2.53\\times10^{-10}\\mathrm{m}$, and the time as $4\\mathrm{h}$. The correct answer is:", "conversion_reason": "The calculation problem has a definite numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "correct_answer": "A", "explanation": "正确答案A通过计算$\\sqrt{\\\\overline{R_{n}^{2}}}=\\\\sqrt{6Dt}$得到，其中扩散系数$D=\\\\frac{1}{6}\\\\Gamma a^{2}$。干扰项B通过错误使用时间单位(分钟而非小时)产生，C和D分别错误应用了扩散系数公式(漏掉系数6或错误平方处理)。这些干扰项利用了材料科学中常见的单位混淆和扩散系数计算错误。", "options": { "A": "1.3 mm", "B": "0.13 mm", "C": "13 μm", "D": "130 μm" }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1113, "question": "Both austenite and pearlite are solid solutions of carbon in $\\alpha-\\mathrm{\\bfFe}$ with a body-centered cubic structure.", "answer": "Wrong! Austenite is a solid solution of carbon in $\\gamma.$ -Fe with a face-centered cubic structure, while pearlite is a two-phase structure composed of ferrite and cementite.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目给出一个陈述（Both austenite and pearlite are solid solutions of carbon in α-Fe with a body-centered cubic structure），要求判断其正确性。答案明确指出该陈述是错误的，并给出了正确的解释。这符合判断题的特征，即判断陈述的对错并给出解释。 | 知识层次: 题目考查对奥氏体和珠光体这两种材料的基本概念的记忆和理解，包括它们的晶体结构和组成。这属于基础概念记忆的范畴。 | 难度: 在选择题中属于中等偏下难度，需要理解并区分奥氏体和珠光体的晶体结构及组成，但不需要复杂的分析或推理。", "convertible": true, "correct_option": "Wrong! Austenite is a solid solution of carbon in $\\gamma.$ -Fe with a face-centered cubic structure, while pearlite is a two-phase structure composed of ferrite and cementite.", "choice_question": "Both austenite and pearlite are solid solutions of carbon in $\\alpha-\\mathrm{\\bfFe}$ with a body-centered cubic structure.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials are inherently brittle at room temperature due to their ionic or covalent bonding nature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle due to their bonding nature, some advanced ceramics like transformation-toughened zirconia can exhibit significant toughness through stress-induced phase transformations. The absolute term 'all' makes this statement incorrect.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 319, "question": "Why is the strength of solid solutions often higher than that of pure metals?", "answer": "Because the different sizes of the two types of atoms in the alloy cause lattice distortion, which hinders dislocation movement and results in solid solution strengthening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么固溶体的强度通常高于纯金属，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释固溶强化的机理，涉及原子尺寸差异导致的晶格畸变以及位错运动的阻碍作用，需要综合运用材料科学中的晶体缺陷和强化机制知识进行推理分析。 | 难度: 在选择题型中，该题目要求考生不仅理解固溶强化的基本概念，还需要掌握晶格畸变和位错运动之间的相互作用机制。这涉及到对材料科学中较为复杂的原理进行解释和分析，属于机理深度解释的层次。虽然题目提供了正确选项，但考生需要具备较高的知识整合能力和推理分析能力才能准确理解并选择正确答案。因此，在选择题型内属于较高难度等级。", "convertible": true, "correct_option": "Because the different sizes of the two types of atoms in the alloy cause lattice distortion, which hinders dislocation movement and results in solid solution strengthening.", "choice_question": "Why is the strength of solid solutions often higher than that of pure metals?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because the different sizes of the two types of atoms in the alloy cause lattice distortion, which hinders dislocation movement", "B": "Because solid solutions have higher atomic packing density than pure metals, increasing resistance to deformation", "C": "Because alloying elements increase the electron density, enhancing metallic bonding strength", "D": "Because the formation of solid solutions reduces grain boundary energy, preventing crack propagation" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual mechanism of solid solution strengthening through lattice distortion and dislocation pinning. Option B is a density-based misconception - packing density doesn't necessarily increase in solid solutions. Option C exploits the intuitive but incorrect link between electron density and strength, ignoring the dominant role of dislocation mechanics. Option D falsely attributes the strengthening to grain boundary effects, which is a different strengthening mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4404, "question": "Cite some disadvantages of forming metals by extrusion as opposed to rolling.", "answer": "The disadvantages of extrusion over rolling are as follows: (1) Nonuniform deformation over the cross-section. (2) A variation in properties may result over a cross-section of an extruded piece.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举挤压成型相对于轧制成型的缺点，答案以文字解释和论述的形式给出，没有选项、判断对错或数值计算的要求。 | 知识层次: 题目考查对金属挤压和轧制两种成型方法的基本概念和特点的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目要求考生理解并记忆金属挤压和轧制两种工艺的基本概念及其优缺点。虽然需要比较两种工艺的差异，但题目仅要求列举挤压相对于轧制的缺点，属于概念解释和描述的层次，不需要复杂的分析或推理。因此，难度等级为2。", "convertible": true, "correct_option": "The disadvantages of extrusion over rolling are as follows: (1) Nonuniform deformation over the cross-section. (2) A variation in properties may result over a cross-section of an extruded piece.", "choice_question": "What are some disadvantages of forming metals by extrusion as opposed to rolling?", "conversion_reason": "The answer is a standard and concise explanation that can be directly used as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Higher surface roughness due to die friction effects", "B": "Lower dimensional accuracy compared to rolling processes", "C": "Increased risk of hydrogen embrittlement during forming", "D": "Reduced formability for high-strength alloys" }, "correct_answer": "A", "explanation": "The correct answer is A because extrusion involves significant friction between the metal and die, leading to higher surface roughness. Option B is incorrect because extrusion can achieve comparable dimensional accuracy to rolling. Option C is a misleading analogy from welding processes, while Option D incorrectly generalizes formability limitations that are process-agnostic.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2580, "question": "Highly cold-rolled aluminum sheets will form a well-developed {001}<100> texture (cube texture) after high-temperature annealing. If such an aluminum sheet is deep-drawn into a cup, how many ears will be produced?", "answer": "Eight ears will be produced during deep drawing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么在深冲过程中会产生八个耳朵，需要文字解释和论述，而不是从选项中选择或简单的对错判断。 | 知识层次: 题目需要理解冷轧铝板在高温退火后形成的立方织构（{001}<100>）及其在深冲过程中的行为。虽然涉及基础概念（织构和深冲），但需要将织构与深冲过程中产生的耳数关联起来，进行一定的分析和应用。这需要多步思考和概念关联，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，需要考生具备以下能力：", "convertible": true, "correct_option": "Eight ears will be produced during deep drawing.", "choice_question": "Highly cold-rolled aluminum sheets will form a well-developed {001}<100> texture (cube texture) after high-temperature annealing. If such an aluminum sheet is deep-drawn into a cup, how many ears will be produced?", "conversion_reason": "The answer is a specific and factual statement, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Eight ears", "B": "Four ears", "C": "Six ears", "D": "No ears will form" }, "correct_answer": "A", "explanation": "The correct answer is A because the cube texture {001}<100> in aluminum sheets exhibits four-fold symmetry in the rolling direction and transverse direction, leading to eight ears during deep drawing (four at 0° and 90°, and four at 45°). Option B is a cognitive bias trap - it exploits the common misconception that cubic symmetry always results in four ears. Option C is a professional intuition trap, designed to catch those who incorrectly analogize with hexagonal materials. Option D is a multi-level verification trap, targeting those who might overlook that even well-annealed materials retain enough texture to cause earing.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1253, "question": "What is the relationship between diffusion flux and concentration gradient?", "answer": "Proportional", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释扩散通量与浓度梯度之间的关系，答案需要文字表述而非选择或判断 | 知识层次: 题目考查扩散通量与浓度梯度之间关系的基本概念记忆，属于材料科学中扩散现象的基础知识，仅需记忆和理解即可回答。 | 难度: 在选择题型中，该题目仅要求记忆基础概念（扩散通量与浓度梯度的关系），属于最简单的定义性知识。正确选项\"Proportional\"直接对应菲克第一定律的基本表述，无需任何推导或分析过程，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Proportional", "choice_question": "What is the relationship between diffusion flux and concentration gradient?", "conversion_reason": "The answer is a standard term that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Proportional (Fick's first law)", "B": "Inversely proportional (Le Chatelier's principle)", "C": "Exponential (Arrhenius relationship)", "D": "Logarithmic (Nernst equation)" }, "correct_answer": "A", "explanation": "The correct answer is A because Fick's first law of diffusion explicitly states that diffusion flux is directly proportional to the concentration gradient. Option B exploits confusion with equilibrium systems where gradients tend to decrease. Option C misapplies the temperature dependence of diffusion coefficients to the flux-gradient relationship. Option D strategically borrows from electrochemistry concepts that are irrelevant to pure diffusion phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1929, "question": "Please write the Burgers vector of the shortest unit dislocation in HCP crystals", "answer": "HCP: a/3<11\\\\bar{2}0>", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求写出HCP晶体中最短单位位错的Burgers矢量，答案需要具体的矢量表示（a/3<11\\\\bar{2}0>），属于需要具体回答的简答题类型，而非选择、判断或计算。 | 知识层次: 题目考查HCP晶体中最短单位位错的Burgers向量的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆HCP晶体中最短单位位错的Burgers向量，属于基础概念记忆性知识，无需解释或分析，解题步骤简单直接。", "convertible": true, "correct_option": "a/3<11\\bar{2}0>", "choice_question": "What is the Burgers vector of the shortest unit dislocation in HCP crystals?", "conversion_reason": "The answer is a standard term in materials science, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "a/3<11\\bar{2}0>", "B": "a/2<110>", "C": "a<0001>", "D": "a/6<11\\bar{2}3>" }, "correct_answer": "A", "explanation": "The correct answer is A because the shortest unit dislocation in HCP crystals occurs along the close-packed <11\\bar{2}0> directions with a magnitude of a/3. Option B is a common FCC dislocation vector, exploiting the cognitive bias of confusing HCP with FCC structures. Option C represents the c-axis vector, a plausible but incorrect choice based on HCP's hexagonal symmetry. Option D is a real dislocation vector in HCP but not the shortest, designed to trap those who recall partial dislocations but fail to identify the minimal Burgers vector.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1374, "question": "What are the differences in morphology, size, and distribution of tertiary cementite?", "answer": "Discontinuous granular, small amount, distributed at ferrite grain boundaries.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释三级渗碳体的形态、尺寸和分布差异，答案以文字描述的形式给出，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对三级渗碳体的形态、尺寸和分布等基本概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目要求考生对三级渗碳体的形态、尺寸和分布有基本的理解和记忆。虽然涉及多个特征（形态、尺寸、分布），但都属于基础概念记忆范畴，且正确选项提供了明确的描述，不需要复杂的分析或比较。因此属于中等难度。", "convertible": true, "correct_option": "Discontinuous granular, small amount, distributed at ferrite grain boundaries", "choice_question": "Which of the following describes the morphology, size, and distribution of tertiary cementite?", "conversion_reason": "The answer is a standard description that can be used as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Discontinuous granular, small amount, distributed at ferrite grain boundaries", "B": "Continuous network, large amount, distributed along prior austenite grain boundaries", "C": "Lamellar structure, moderate amount, alternating with ferrite layers", "D": "Spherical particles, trace amount, uniformly dispersed in matrix" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes tertiary cementite's characteristics: it forms as discontinuous granular particles in small quantities at ferrite grain boundaries. Option B is a cognitive bias trap, describing secondary cementite which forms continuous networks. Option C exploits intuition by mimicking pearlite structure. Option D uses spherical morphology which is typical of spheroidized cementite, not tertiary cementite.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1943, "question": "In an FCC crystal, does the dislocation reaction a/2[10-1] + a/6[-121] → a/3[11-1] satisfy the geometric conditions?", "answer": "Geometric conditions: b1 + b2 = (1/2 - 1/6)a + (0 + 2/6)b + (-1/2 + 1/6)c = 1/3a + 1/3b - 1/3c = a/3[11-1], satisfying the geometric conditions.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断一个具体的陈述（位错反应是否满足几何条件）的对错，答案给出了明确的判断依据和计算过程，符合判断题的特征 | 知识层次: 题目涉及位错反应几何条件的验证，需要进行多步计算和概念关联，包括矢量相加和验证是否符合几何条件。虽然不涉及复杂的推理分析或机理解释，但需要一定的综合分析能力。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目要求考生理解FCC晶体中的位错反应，并能够进行矢量计算。其次，解题过程涉及多步计算（矢量相加和分量计算），需要考生具备较强的空间想象能力和数学运算能力。最后，题目要求考生综合判断几何条件是否满足，这需要对位错反应的基本原理有深入理解。因此，该题目在选择题型中属于综合分析结果判断的难度等级。", "convertible": true, "correct_option": "Geometric conditions: b1 + b2 = (1/2 - 1/6)a + (0 + 2/6)b + (-1/2 + 1/6)c = 1/3a + 1/3b - 1/3c = a/3[11-1], satisfying the geometric conditions.", "choice_question": "In an FCC crystal, does the dislocation reaction a/2[10-1] + a/6[-121] → a/3[11-1] satisfy the geometric conditions?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In FCC crystals, all dislocation reactions that satisfy the geometric conditions also necessarily satisfy the energy conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While geometric conditions (Burgers vector conservation) are necessary for dislocation reactions, energy conditions (reduction in total elastic energy) must also be satisfied. Some geometrically possible reactions may be energetically unfavorable. This is a common misconception where students overlook the dual requirement for dislocation reactions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2203, "question": "Based on the minimum recrystallization temperature of copper being 542 K, determine the recrystallization annealing temperature for copper", "answer": "The recrystallization annealing temperature for copper T=643∼743 K", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求基于给定的最低再结晶温度（542 K）来确定铜的再结晶退火温度，并给出了具体的温度范围（643∼743 K）。这需要根据材料科学中的相关公式或经验法则进行计算或推导，属于需要数值计算和公式应用的题型。 | 知识层次: 题目需要应用已知的铜最低再结晶温度（542 K）来计算再结晶退火温度范围（643∼743 K），属于基本公式应用和简单计算，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用已知的铜再结晶温度（542 K）来确定再结晶退火温度范围（643~743 K）。题目属于单一公式直接计算类型，无需复杂推导或多步骤分析，符合等级1的难度标准。", "convertible": true, "correct_option": "T=643∼743 K", "choice_question": "Based on the minimum recrystallization temperature of copper being 542 K, what is the recrystallization annealing temperature for copper?", "conversion_reason": "The answer is a specific range, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "643-743 K", "B": "542-600 K", "C": "400-500 K", "D": "800-900 K" }, "correct_answer": "A", "explanation": "The correct answer is A (643-743 K) because recrystallization annealing temperature is typically 100-200°C above the minimum recrystallization temperature (542 K). Option B (542-600 K) is a cognitive bias trap, using the minimum recrystallization temperature as the lower bound. Option C (400-500 K) exploits the misconception that annealing can occur below recrystallization temperature. Option D (800-900 K) is a professional intuition trap, using values appropriate for steel but too high for copper.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3157, "question": "The density of $\\\\mathrm{CaF}_{2}$ is $\\\\rho=3.18~\\\\mathrm{g/cm}^{3}$, the relative atomic mass of $\\\\mathrm{Ca}$ is $A_{\\\\mathrm{r}}=40.08$, and the relative atomic mass of $\\\\mathrm{F}$ is $A_{\\\\mathrm{r}}=19.00$. Find the lattice constant $a$.", "answer": "From the structure of $\\\\mathrm{CaF}_{2}$, it is known that the unit cell contains 4 $\\\\mathrm{Ca}^{2+}$ ions and 8 $\\\\mathrm{F^{-}}$ ions. Therefore, the relationship between its density and the lattice constant is as follows: $$ x\\\\rho=\\\\frac{4\\\\times\\\\frac{40.08+19\\\\times2}{6.023\\\\times10^{23}}}{a^{3}}\\\\approx3.18 $$ Solving the above equation gives $a=0.546(\\\\mathrm{nm})$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解晶格常数a，答案中包含了具体的计算步骤和最终数值结果。 | 知识层次: 题目需要进行多步计算，包括单位晶胞中离子数量的确定、相对原子质量的计算、密度与晶格常数的关系公式应用，以及最终的数值求解。这需要综合运用材料科学中的晶体结构知识和数学计算能力，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、密度计算、单位换算等多个概念，并进行多步骤的综合计算。虽然题目提供了关键参数，但解题过程涉及单位转换和代数求解，对学生的综合能力要求较高。", "convertible": true, "correct_option": "0.546 nm", "choice_question": "The density of $\\mathrm{CaF}_{2}$ is $\\rho=3.18~\\mathrm{g/cm}^{3}$, the relative atomic mass of $\\mathrm{Ca}$ is $A_{\\mathrm{r}}=40.08$, and the relative atomic mass of $\\mathrm{F}$ is $A_{\\mathrm{r}}=19.00$. What is the lattice constant $a$?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.546 nm", "B": "0.463 nm", "C": "0.382 nm", "D": "0.618 nm" }, "correct_answer": "A", "explanation": "正确答案A是通过正确计算CaF2的晶格常数得到的。CaF2具有面心立方结构，每个晶胞含有4个CaF2分子。计算步骤包括：1)计算摩尔质量(40.08 + 2×19.00=78.08 g/mol)；2)计算晶胞质量(78.08×4/6.022×10^23=5.19×10^-22 g)；3)利用密度公式ρ=m/V得到晶胞体积V=1.63×10^-22 cm^3；4)立方体边长a=V^(1/3)=0.546 nm。干扰项B(0.463 nm)是错误假设每个晶胞只有1个CaF2分子计算得到的结果，利用了简单立方结构的认知偏差。干扰项C(0.382 nm)是错误使用CaO的晶格常数，利用了材料类比误区。干扰项D(0.618 nm)是错误假设了体心立方结构计算的结果，利用了晶体结构判断的直觉陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 187, "question": "A bubble with a radius of $5\\\\times10^{-8}\\\\mathrm{m}$ forms at a depth of $20\\\\mathrm{cm}$ in a quartz glass melt. The melt density is $2200\\\\mathrm{kg/m}^{3}$, the surface tension is $0.29\\\\mathrm{N/m}$, and the atmospheric pressure is $1.01\\\\times10^{5}\\\\mathrm{Pa}$. What is the minimum internal pressure required to form this bubble?", "answer": "Solution: \\( P_1 \\) (static pressure of the melt column) \\( = h \\\\rho g = 0.2 \\\\times 2200 \\\\times 9.81 = 4316.4 \\\\, \\\\text{Pa} \\)\\n\\nAdditional pressure:\\n\\\\[\\n\\\\Delta P = \\\\frac{2\\\\gamma}{r} = \\\\frac{2 \\\\times 0.29}{5 \\\\times 10^{-8}} = 1.16 \\\\times 10^7 \\\\, \\\\text{Pa}\\n\\\\]\\n\\nTherefore, the minimum pressure required to form this bubble is:\\n\\\\[\\nP = P_1 + \\\\Delta P + P_{\\\\text{atmospheric}} = 4316.4 + 1.16 \\\\times 10^7 + 1.01 \\\\times 10^5 = 117.04 \\\\times 10^5 \\\\, \\\\text{Pa}\\n\\\\]", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解气泡形成所需的最小内部压力，答案中包含了具体的计算步骤和结果。 | 知识层次: 题目涉及多步计算和概念关联，需要综合应用静压力公式、表面张力公式以及大气压力的概念，并进行数值计算和综合分析。虽然不涉及复杂的推理分析或机理解释，但需要一定的思维深度和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（静压力、表面张力、大气压力）并进行多步计算。虽然题目提供了所有必要参数，但计算过程涉及多个步骤和单位转换，需要较强的综合分析能力。", "convertible": true, "correct_option": "117.04 × 10^5 Pa", "choice_question": "A bubble with a radius of $5\\times10^{-8}\\mathrm{m}$ forms at a depth of $20\\mathrm{cm}$ in a quartz glass melt. The melt density is $2200\\mathrm{kg/m}^{3}$, the surface tension is $0.29\\mathrm{N/m}$, and the atmospheric pressure is $1.01\\times10^{5}\\mathrm{Pa}$. What is the minimum internal pressure required to form this bubble?", "conversion_reason": "The problem is a calculation question with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "117.04 × 10^5 Pa", "B": "1.17 × 10^5 Pa", "C": "29.4 × 10^5 Pa", "D": "220.8 × 10^5 Pa" }, "correct_answer": "A", "explanation": "正确答案A是通过考虑静水压力(ρgh=2200×9.81×0.2=4316.4 Pa)、大气压力(1.01×10^5 Pa)和拉普拉斯压力(2γ/r=2×0.29/5×10^-8=11.6×10^6 Pa)的总和计算得出。干扰项B错误地忽略了拉普拉斯压力的主导作用；干扰项C仅计算了静水压力与拉普拉斯压力的简单相加；干扰项D错误地将密度直接乘以表面张力。这些干扰项利用了AI对微小尺度下表面张力效应可能低估的认知偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1428, "question": "What is the most close-packed direction in a face-centered cubic crystal?", "answer": "<110>", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个特定的晶体学方向，答案是一个具体的晶体学指数<110>，不需要计算或选择，属于需要直接回答的简答题类型。 | 知识层次: 题目考查对晶体结构中密排方向的基本概念记忆，属于基础概念记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅考察对最密排方向的基础概念记忆，属于最基础的定义简答级别。学生只需记住面心立方晶体中最密排方向是<110>即可作答，不需要进行任何解释或复杂分析。", "convertible": true, "correct_option": "<110>", "choice_question": "What is the most close-packed direction in a face-centered cubic crystal?", "conversion_reason": "The answer is a standard term in crystallography, making it suitable for conversion to a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "<110>", "B": "<111>", "C": "<100>", "D": "<112>" }, "correct_answer": "A", "explanation": "The <110> direction is the most close-packed in FCC crystals because it aligns atoms along the face diagonal where the atomic spacing is minimized. Option B (<111>) is a common trap as it's the close-packed direction in BCC crystals. Option C (<100>) exploits the cube edge intuition but has lower atomic density. Option D (<112>) uses a less common direction that appears plausible but doesn't maximize atomic contact.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4077, "question": "[b] Tungsten is the lowest density metal that has structural use.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（F表示错误），符合判断题的特征。 | 知识层次: 题目考查对钨金属基本性质（密度）的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念正误判断题，仅需记忆钨的基本物理性质（密度）及其在结构材料中的定位。题目陈述简单明确，只需判断\"钨是结构用金属中密度最低的\"这一说法的正误，无需进行复杂的概念分析或比较。在选择题型中，这属于最基础的知识记忆层次，因此难度等级为1。", "convertible": true, "correct_option": "F", "choice_question": "[b] Tungsten is the lowest density metal that has structural use.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior under all loading conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While ceramics are generally brittle, certain advanced ceramics can exhibit limited ductility under specific conditions (e.g., high temperatures or hydrostatic pressure). The use of 'all' and 'under all loading conditions' makes this statement false. This tests understanding of material behavior exceptions and absolute terminology.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 763, "question": "In macroscopic crystals, the symmetry elements present must all pass through the center of the crystal", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对晶体对称性基础概念的简单记忆和理解，不需要复杂的分析或应用。 | 难度: 该题目属于基础概念记忆层次，仅需判断对称元素是否必须通过晶体中心这一基本定义的正确性。在选择题型中，这种直接的正误判断题属于最简单的难度等级，不需要复杂的理解或分析过程。", "convertible": true, "correct_option": "√", "choice_question": "In macroscopic crystals, the symmetry elements present must all pass through the center of the crystal", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In macroscopic crystals, the symmetry elements present must all pass through the center of the crystal", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "In macroscopic crystals, all symmetry elements must indeed pass through a common point (the center of symmetry). This is a fundamental requirement of crystallographic symmetry operations in three-dimensional space. The statement is correct because symmetry operations must leave the crystal looking identical before and after the operation, which necessitates all symmetry elements intersecting at the center. A common misconception might be that some symmetry elements could exist independently of the center, but this would violate the definition of point group symmetry in crystals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 616, "question": "From what is Fe3CII precipitated", "answer": "Austenite", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目以提问形式要求回答Fe3CII的沉淀来源，答案\"Austenite\"是一个简短的专有名词回答，不需要计算或选择，符合简答题的特征 | 知识层次: 题目考查Fe3CII从何种相中析出的基础概念记忆，属于材料科学中相变的基本知识点，不需要复杂的推理或综合分析。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即Fe3CII从何种相中析出这一简单事实。正确选项\"Austenite\"是材料科学中最基本的相变知识点之一，无需复杂推理或概念比较，属于直接回忆型问题。", "convertible": true, "correct_option": "Austenite", "choice_question": "From what is Fe3CII precipitated?", "conversion_reason": "The answer is a standard term (Austenite), which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Austenite", "B": "Ferrite", "C": "Cementite", "D": "Pearlite" }, "correct_answer": "A", "explanation": "Fe3CII (secondary cementite) precipitates from austenite during cooling of hypereutectoid steels. The key confusion comes from: (B) Ferrite is a common but incorrect first guess due to its association with iron-carbon phases. (C) Cementite is a tempting choice due to the chemical formula similarity but is actually the precipitate itself. (D) Pearlite creates confusion by being a two-phase structure containing cementite, making it seem plausible as a source.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2363, "question": "Why do commercial oxides such as windows and beverage glass require the addition of Na2O to SiO2?", "answer": "Na2O cannot form a network in glass. Sodium ions have only one functionality, Na+ has only one functionality. When they are added to the SiO2 network and connected with oxygen ions, they inevitably break a primary bond of the network, reducing the density of primary bonds in the network and thereby lowering the glass transition temperature. For general wide-mouth bottles and window glass, which are used at low temperatures, they do not require an excessively high glass transition temperature Tg. A low Tg makes the products easier to handle and reduces costs.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么商业氧化物如窗户和饮料玻璃需要添加Na2O到SiO2中，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释Na2O在商业氧化物玻璃中的作用机制，涉及网络形成体与非网络形成体的概念、玻璃结构的变化、玻璃转变温度的影响因素等多方面的知识。需要综合运用材料科学中的玻璃结构理论，分析Na2O的加入如何破坏SiO2网络结构，并解释其对玻璃性能的影响。这种题目不仅需要理解基本概念，还需要进行机理层面的推理和分析，属于复杂分析的层次。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Na2O cannot form a network in glass. Sodium ions have only one functionality, Na+ has only one functionality. When they are added to the SiO2 network and connected with oxygen ions, they inevitably break a primary bond of the network, reducing the density of primary bonds in the network and thereby lowering the glass transition temperature. For general wide-mouth bottles and window glass, which are used at low temperatures, they do not require an excessively high glass transition temperature Tg. A low Tg makes the products easier to handle and reduces costs.", "choice_question": "Why do commercial oxides such as windows and beverage glass require the addition of Na2O to SiO2?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Na2O disrupts the SiO2 network by breaking primary bonds, lowering Tg for easier processing", "B": "Na2O increases the refractive index for better optical clarity in windows", "C": "Na2O forms secondary bonds that improve mechanical strength at room temperature", "D": "Na2O creates charge-balancing defects that enhance thermal conductivity" }, "correct_answer": "A", "explanation": "Correct answer A explains the fundamental network modifier effect where monovalent Na+ breaks Si-O-Si bonds. Option B exploits optical property confusion (refractive index is mainly determined by SiO2). Option C uses mechanical strength misconception (network modifiers typically decrease strength). Option D creates a thermal properties red herring (defects usually decrease thermal conductivity).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2669, "question": "One of the allotropes of Mn has a cubic structure with a lattice constant a of 0.632nm, ρ of 7.26g/cm³, and Ar of 54.94. How many atoms are there in the Mn unit cell?", "answer": "According to the formula ρ = (n * Ar) / (a³ * NA), it can be derived that n = (ρ * a³ * NA) / Ar. Substituting the data: n = (7.26 * (6.32 * 10^-8)^3 * 6.023 * 10^23) / 54.94 = 20.091 ≈ 20. Therefore, there are 20 atoms in each unit cell.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解单位晶胞中的原子数量，答案涉及具体的计算过程和结果。 | 知识层次: 题目需要进行多步计算，包括密度公式的应用、单位转换和数值计算，同时需要理解晶格常数、密度和原子量之间的关系。虽然不涉及复杂的推理分析，但需要综合运用多个概念进行计算。 | 难度: 在选择题中属于中等偏上难度，需要掌握晶体结构、密度计算和单位换算等多个概念，并进行多步骤的综合计算。虽然题目提供了公式和数据，但需要正确代入和运算，涉及单位转换和科学计数法的处理，对学生的计算能力和概念理解有一定要求。", "convertible": true, "correct_option": "20", "choice_question": "One of the allotropes of Mn has a cubic structure with a lattice constant a of 0.632nm, ρ of 7.26g/cm³, and Ar of 54.94. How many atoms are there in the Mn unit cell?", "conversion_reason": "The calculation question has a definite numerical answer, making it suitable for conversion into a multiple-choice format where the correct option is the calculated result.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "选项B", "C": "20", "D": "选项D" }, "correct_answer": "C", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1295, "question": "Why does pure metal grow in a planar manner during solidification under a positive temperature gradient?", "answer": "During crystallization, the interface of pure metal is rough and grows under a positive temperature gradient. As the crystal grows, heat is dissipated through the solid mold wall, making the solid-liquid interface isothermal. If dynamic undercooling is achieved, the interface moves forward. If there is a small protrusion locally on the interface extending into the superheated liquid phase, the protrusion will be melted, so the interface remains straight; the crystal grows in a planar manner.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释纯金属在正温度梯度下凝固时为何以平面方式生长，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要解释纯金属在正温度梯度下凝固时平面生长的机理，涉及动态过冷、界面粗糙性、热量传递等多个概念的关联和综合分析，需要深入理解并推理分析其背后的物理机制。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "During crystallization, the interface of pure metal is rough and grows under a positive temperature gradient. As the crystal grows, heat is dissipated through the solid mold wall, making the solid-liquid interface isothermal. If dynamic undercooling is achieved, the interface moves forward. If there is a small protrusion locally on the interface extending into the superheated liquid phase, the protrusion will be melted, so the interface remains straight; the crystal grows in a planar manner.", "choice_question": "Why does pure metal grow in a planar manner during solidification under a positive temperature gradient?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The protrusion into superheated liquid experiences higher melting rate due to thermal conductivity differences", "B": "Surface tension forces dominate at the atomic scale to maintain planar growth", "C": "The positive temperature gradient creates a thermodynamic barrier to dendritic formation", "D": "Latent heat release automatically stabilizes the solid-liquid interface geometry" }, "correct_answer": "A", "explanation": "Correct answer A addresses the key mechanism where protrusions into superheated liquid melt faster due to thermal gradients. Option B misapplies surface tension concepts that are irrelevant at this scale. Option C sounds plausible but incorrectly attributes the effect to thermodynamics rather than kinetics. Option D contains a half-truth about latent heat but misses the critical interface stability mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 79, "question": "What is the effect of forming a solid solution on the mechanical properties of materials?", "answer": "Solid solution strengthening; the dissolution of solute atoms increases the strength and hardness of the solid solution. The strength and hardness of the solid solution are often higher than those of the constituent elements, while the plasticity is lower.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释固溶体对材料机械性能的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对固溶体强化这一基本概念的记忆和理解，属于材料科学中的基本原理和现象解释，不涉及复杂的计算或综合分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（固溶强化），但正确选项不仅需要识别\"固溶强化\"这一概念，还需要理解其对机械性能的具体影响（强度硬度增加、塑性降低）。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。题目要求考生能够将固溶强化的基本原理与材料性能变化联系起来，属于概念解释和描述的难度层次。", "convertible": true, "correct_option": "Solid solution strengthening; the dissolution of solute atoms increases the strength and hardness of the solid solution. The strength and hardness of the solid solution are often higher than those of the constituent elements, while the plasticity is lower.", "choice_question": "What is the effect of forming a solid solution on the mechanical properties of materials?", "conversion_reason": "The answer is a standard terminology and concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening occurs, increasing yield strength but decreasing ductility due to lattice distortion", "B": "The elastic modulus increases proportionally with solute concentration while maintaining constant ductility", "C": "Dislocation mobility is enhanced, leading to simultaneous increase in both strength and ductility", "D": "The primary effect is grain boundary strengthening, with solute atoms segregating to grain boundaries" }, "correct_answer": "A", "explanation": "Correct answer A describes the well-established solid solution strengthening mechanism where solute atoms distort the lattice and impede dislocation motion. Option B is a cognitive bias trap - elastic modulus is an intrinsic property largely unaffected by solute concentration. Option C is a professional intuition trap - dislocation mobility should decrease, not increase. Option D is a multi-level verification trap - while grain boundary segregation can occur, it's not the primary strengthening mechanism in solid solutions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4232, "question": "What is the composition, in weight percent, of an alloy that consists of 6 at% \\mathrm{Pb} and 94 \\mathrm{at}% \\mathrm{Sn} ?", "answer": "the composition of the alloy is: 1. 10.0 \\, \\text{wt% pb} 2. 90.0 \\, \\text{wt% sn}", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（原子百分比转换为重量百分比）来确定合金的组成，答案以具体数值形式给出。 | 知识层次: 题目涉及基本的原子百分比到重量百分比的转换计算，需要应用简单的公式和基本的元素质量数据，属于直接套用基本公式的简单应用层次。 | 难度: 在选择题型中，该题目需要应用基本的原子百分比与重量百分比转换公式，并进行简单的计算。虽然涉及公式应用，但步骤直接且不复杂，属于简单公式应用计算。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "1. 10.0 wt% Pb 2. 90.0 wt% Sn", "choice_question": "What is the composition, in weight percent, of an alloy that consists of 6 at% Pb and 94 at% Sn?", "conversion_reason": "The answer is a specific and discrete set of values, making it suitable for conversion into a multiple-choice format where the correct options can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "10.0 wt% Pb, 90.0 wt% Sn", "B": "6.0 wt% Pb, 94.0 wt% Sn", "C": "15.2 wt% Pb, 84.8 wt% Sn", "D": "3.5 wt% Pb, 96.5 wt% Sn" }, "correct_answer": "A", "explanation": "The correct answer requires converting atomic percent to weight percent using the atomic weights of Pb (207.2 g/mol) and Sn (118.71 g/mol). Option B is a direct copy of atomic percentages, exploiting the cognitive bias of assuming identical numerical values. Option C reverses the expected trend by making Pb appear more dominant, playing on misconceptions about heavier elements. Option D introduces arbitrary numbers that might seem plausible for dilute alloys, targeting incorrect intuition about concentration effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3727, "question": "(b) The flexural modulus of alumina is 45 × 10^{6} psi and its flexural strength is 46,000 psi. A bar of alumina 0.3 in. thick, 1.0 in. wide, and 10 in. long is placed on supports 7 in. apart. Determine the amount of deflection at the moment the bar breaks, assuming that no plastic deformation occurs.", "answer": "the deflection at the moment the bar breaks is 0.0278 in.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定氧化铝棒断裂时的挠度，答案是一个具体的数值结果（0.0278 in.），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括应用弹性力学中的梁弯曲公式，计算挠度，并关联材料的力学性能参数（弹性模量和弯曲强度）。虽然不涉及复杂的综合分析或创新应用，但需要一定的概念关联和计算步骤。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如弹性模量、弯曲强度、梁的挠度计算等）并进行多步骤计算。题目要求考生综合运用材料力学和弹性理论的知识，通过公式推导和数值计算得出最终结果。虽然选择题提供了正确选项，但解题过程涉及多个关键步骤和概念关联，对考生的综合分析能力有一定要求。", "convertible": true, "correct_option": "0.0278 in.", "choice_question": "The flexural modulus of alumina is 45 × 10^{6} psi and its flexural strength is 46,000 psi. A bar of alumina 0.3 in. thick, 1.0 in. wide, and 10 in. long is placed on supports 7 in. apart. Determine the amount of deflection at the moment the bar breaks, assuming that no plastic deformation occurs. The deflection is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0278 in.", "B": "0.0421 in.", "C": "0.0186 in.", "D": "0.0355 in." }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算得到的，使用公式δ = (FL^3)/(48EI)，其中F是根据弯曲强度计算的断裂载荷，I是惯性矩。干扰项B错误地使用了剪切模量而非弯曲模量进行计算。干扰项C错误地假设了塑性变形的影响。干扰项D则错误地使用了错误的支撑距离参数。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 803, "question": "What are the methods of alloy strengthening?", "answer": "Grain refinement strengthening, solid solution strengthening, multiphase strengthening, dispersion strengthening (age hardening), and work hardening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举合金强化的方法，答案是通过文字解释和论述的形式给出，没有提供选项或要求判断对错，也不需要数值计算。 | 知识层次: 题目考查合金强化方法的基本分类和记忆，属于基础概念的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生掌握合金强化的多种方法（晶粒细化强化、固溶强化、多相强化、弥散强化/时效硬化、加工硬化），并能准确识别和区分这些方法。这比单纯记忆单个定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "Grain refinement strengthening, solid solution strengthening, multiphase strengthening, dispersion strengthening (age hardening), and work hardening", "choice_question": "Which of the following are the methods of alloy strengthening?", "conversion_reason": "The answer is a standard list of terms related to alloy strengthening, which can be converted into a multiple-choice question format by presenting these terms as options and asking the student to select the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain refinement strengthening", "B": "Martensitic transformation without alloying", "C": "Solid solution strengthening", "D": "Recrystallization annealing" }, "correct_answer": "B", "explanation": "The correct answer is B because martensitic transformation without alloying is not a method of alloy strengthening, it's a phase transformation phenomenon. Option A and C are valid strengthening methods. Option D is a heat treatment process that softens metals, not strengthens them. The trap here is that martensitic transformation is often associated with strengthening in steels, but only when combined with alloying elements - the question specifically excludes alloying.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 296, "question": "What effect does a nucleating agent have on the critical nucleus radius r* during melt crystallization?", "answer": "Using a nucleating agent can reduce ?s, thus r* decreases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释核化剂对临界核半径的影响，答案提供了简短的文字解释而非计算或选择 | 知识层次: 题目需要理解成核剂对临界核半径的影响机制，涉及表面能变化(Δσ)与临界半径(r*)的关联分析，属于概念关联和中等程度的应用分析。虽然不涉及多步计算，但需要理解Gibbs-Thomson方程的基本应用，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解成核剂对临界核半径的影响机制，并关联表面能（Δs）与临界核半径（r*）的关系。虽然不涉及多步计算，但需要对概念进行综合分析。", "convertible": true, "correct_option": "Using a nucleating agent can reduce ?s, thus r* decreases.", "choice_question": "What effect does a nucleating agent have on the critical nucleus radius r* during melt crystallization?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Using a nucleating agent can reduce ?s, thus r* decreases", "B": "Nucleating agents increase surface energy ?s, leading to larger r*", "C": "The critical radius r* remains unchanged as it depends only on undercooling ?T", "D": "Nucleating agents eliminate the need for critical nucleus formation" }, "correct_answer": "A", "explanation": "The correct answer is A because nucleating agents reduce the interfacial energy (?s) between the nucleus and the melt, which directly decreases the critical nucleus radius (r*) according to the Gibbs-Thomson equation. Option B is a cognitive bias trap that reverses the actual effect of nucleating agents on surface energy. Option C exploits the common misconception that r* depends solely on undercooling while ignoring the ?s term in the equation. Option D is an extreme statement that misrepresents the fundamental crystallization mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1985, "question": "Determine whether the following dislocation reaction can proceed: $\\\\frac{a}{2}[10\\\\overline{{{1}}}]+\\\\frac{a}{6}[\\\\overline{{{1}}}21]\\\\rightarrow\\\\frac{a}{3}[11\\\\overline{{{1}}}]$", "answer": "Yes. Geometric condition: $\\\\sum b_{\\\\tt H}=\\\\sum b_{\\\\tt G}=\\\\frac{\\\\alpha}{3}[11\\\\overline{{1}}]$; energy condition: $\\\\sum b_{\\\\mathbb{H}}^{2}={\\\\frac{2}{3}}a^{2}>$ $\\\\sum b_{E}^{2}={\\\\frac{1}{3}}a^{2}.$", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断位错反应是否能够进行，答案给出了明确的\"yes\"判断，并提供了几何条件和能量条件的验证，符合判断题的特征。 | 知识层次: 题目需要应用位错反应的能量条件和几何条件进行判断，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目要求判断位错反应是否可以进行，这需要理解位错反应的几何条件和能量条件。其次，解题过程涉及多个步骤的计算和概念的综合应用，包括矢量运算和能量比较。虽然题目提供了正确选项，但学生仍需具备扎实的基础知识和综合分析能力才能正确判断。因此，在选择题型内，该题目属于等级4的难度。", "convertible": true, "correct_option": "Yes. Geometric condition: $\\\\sum b_{\\\\tt H}=\\\\sum b_{\\\\tt G}=\\\\frac{\\\\alpha}{3}[11\\\\overline{{1}}]$; energy condition: $\\\\sum b_{\\\\mathbb{H}}^{2}={\\\\frac{2}{3}}a^{2}>$ $\\\\sum b_{E}^{2}={\\\\frac{1}{3}}a^{2}.$", "choice_question": "Determine whether the following dislocation reaction can proceed: $\\\\frac{a}{2}[10\\\\overline{{{1}}}]+\\\\frac{a}{6}[\\\\overline{{{1}}}21]\\\\rightarrow\\\\frac{a}{3}[11\\\\overline{{{1}}}]$", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All dislocation reactions in FCC crystals must satisfy both the geometric and energy conditions to proceed.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most dislocation reactions in FCC crystals require both geometric and energy conditions to be satisfied, there are exceptional cases where reactions may proceed under specific stress conditions or in the presence of defects even if the energy condition is not strictly met. The use of 'all' makes this statement incorrect as it does not account for these exceptions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4893, "question": "List two important advantages of hybrid composites over normal fiber composites.", "answer": "Two advantages of hybrid composites are: (1) better overall property combinations, and (2) failure is not as catastrophic as with single-fiber composites.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举混合复合材料的两个重要优势，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对混合复合材料优势的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目要求考生回忆并列举两种混合复合材料的优势，属于概念解释和描述的层次。虽然需要记忆具体知识点，但不需要复杂的分析或比较，相对直接。因此属于中等难度。", "convertible": true, "correct_option": "better overall property combinations, and failure is not as catastrophic as with single-fiber composites", "choice_question": "Which of the following are two important advantages of hybrid composites over normal fiber composites?", "conversion_reason": "The answer is a standard list of advantages that can be presented as options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Better overall property combinations and less catastrophic failure modes", "B": "Higher specific stiffness and improved thermal conductivity in all directions", "C": "Reduced interfacial bonding strength but enhanced fatigue resistance", "D": "Lower density and isotropic mechanical properties" }, "correct_answer": "A", "explanation": "Correct answer A reflects the two key advantages: hybrid composites combine benefits of different fibers for optimized properties, and their failure is more gradual due to fiber redundancy. Option B is a cognitive bias trap - while stiffness may improve, thermal conductivity enhancement is not guaranteed in all directions. Option C exploits professional intuition by mixing real but unrelated phenomena (interfacial bonding vs fatigue). Option D is a multi-level trap - while density may reduce, isotropic properties are impossible in fiber composites.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1557, "question": "10. First-order phase transition", "answer": "A phase transition where the free energies of the old and new phases are equal before and after the transition, but their first-order partial derivatives are unequal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"First-order phase transition\"进行文字解释和论述，答案是一个详细的定义描述，符合简答题的特征。 | 知识层次: 题目考查一级相变的基本定义和特征，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆一级相变的定义，即自由能在相变前后相等但一阶偏导数不等。虽然需要掌握一定的概念知识，但不需要复杂的分析或比较多个概念，因此属于中等难度。", "convertible": true, "correct_option": "A phase transition where the free energies of the old and new phases are equal before and after the transition, but their first-order partial derivatives are unequal.", "choice_question": "Which of the following best describes a first-order phase transition?", "conversion_reason": "The answer is a standard definition of a first-order phase transition, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A phase transition where the free energies of the old and new phases are equal before and after the transition, but their first-order partial derivatives are unequal", "B": "A phase transition characterized by a discontinuous change in the first derivative of Gibbs free energy with respect to temperature", "C": "A phase transition where the crystal structure changes without any latent heat absorption or release", "D": "A phase transition exhibiting a divergence in the second derivative of Gibbs free energy while the first derivative remains continuous" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a first-order phase transition where the first derivatives of Gibbs free energy (entropy and volume) are discontinuous. Option B is a cognitive bias trap - while it mentions discontinuity, it incorrectly specifies 'first derivative with respect to temperature' only, omitting the pressure dependence. Option C is a professional intuition trap, describing a second-order transition's characteristic (no latent heat) while mentioning crystal structure change which is common in first-order transitions. Option D is a multi-level verification trap, perfectly describing a second-order transition while using terminology that might confuse AI models about the order of derivatives involved.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1241, "question": "When dΔG/dr=0, what is the obtained 'r' value called?", "answer": "Critical nucleus radius", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述特定概念（临界核半径），不需要计算或选择选项 | 知识层次: 题目考查对临界核半径这一基本概念的记忆和理解，属于定义性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对\"Critical nucleus radius\"这一基础定义的记忆，不需要解释或复杂分析，属于最基本的概念记忆题。", "convertible": true, "correct_option": "Critical nucleus radius", "choice_question": "When dΔG/dr=0, what is the obtained 'r' value called?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Critical nucleus radius", "B": "Gibbs free energy minimum", "C": "Activation energy barrier", "D": "Equilibrium grain size" }, "correct_answer": "A", "explanation": "The correct answer is A because dΔG/dr=0 mathematically defines the critical radius where the nucleus becomes stable. Option B exploits the cognitive bias of associating zero derivative with energy minima. Option C targets confusion between nucleation kinetics and thermodynamics. Option D leverages grain growth analogy which is irrelevant to nucleation theory.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4510, "question": "For the following pair of polymers, do the following: (1) state whether or not it is possible to decide whether one polymer has a higher tensile strength than the other; (2) if this is possible, note which has the higher tensile strength and then cite the reason(s) for your choice; and (3) if it is not possible to decide, then state why. Syndiotactic polystyrene having a number-average molecular weight of 600,000 g/mol; atactic polystyrene having a number-average molecular weight of 500,000 g/mol", "answer": "Yes it is possible. The syndiotactic polystyrene has the higher tensile strength. Syndiotactic polymers are more likely to crystallize than atactic ones; the greater the crystallinity, the higher the tensile strength. Furthermore, the syndiotactic also has a higher molecular weight; increasing molecular weight also enhances the strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对两种聚合物的拉伸强度进行比较，并解释原因。答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目要求比较两种聚合物的拉伸强度，并解释原因。这需要理解分子量、立体规整性（如间规立构和无规立构）对聚合物性能的影响，以及这些因素如何共同影响拉伸强度。虽然不涉及复杂的计算或多步推理，但需要对多个概念进行关联和综合分析。 | 难度: 在选择题型中，该题目要求考生进行多角度分析论述。首先需要判断是否可能比较两种聚合物的拉伸强度，然后需要分析两种聚合物的结构差异（间规与无规）和分子量差异对拉伸强度的影响。此外，还需要理解结晶度与拉伸强度的关系以及分子量对强度的影响。这些步骤涉及多个概念的关联和综合分析，超出了简单的记忆或单一概念的应用，因此在选择题型中属于较高难度。", "convertible": true, "correct_option": "The syndiotactic polystyrene has the higher tensile strength. Syndiotactic polymers are more likely to crystallize than atactic ones; the greater the crystallinity, the higher the tensile strength. Furthermore, the syndiotactic also has a higher molecular weight; increasing molecular weight also enhances the strength.", "choice_question": "For the following pair of polymers, which one has a higher tensile strength and why? Syndiotactic polystyrene having a number-average molecular weight of 600,000 g/mol; atactic polystyrene having a number-average molecular weight of 500,000 g/mol", "conversion_reason": "The original question asks for a comparison and explanation, which can be effectively converted into a multiple-choice question by providing the correct option as the answer. The answer is a standard explanation that can be presented as a choice.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The syndiotactic polystyrene has higher tensile strength due to its higher crystallinity and molecular weight", "B": "The atactic polystyrene has higher tensile strength because lower molecular weight polymers have better chain mobility", "C": "Both polymers have equal tensile strength as molecular weight differences are compensated by tacticity effects", "D": "Cannot be determined without knowing the degree of polymerization" }, "correct_answer": "A", "explanation": "The correct answer is A because syndiotactic polymers crystallize more readily than atactic ones, and higher crystallinity increases tensile strength. Additionally, the higher molecular weight of syndiotactic polystyrene further enhances its strength. Option B is incorrect because while lower MW polymers do have better chain mobility, this actually reduces tensile strength. Option C is a balance fallacy - the effects don't compensate equally. Option D is incorrect because number-average molecular weight is sufficient for this comparison.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4444, "question": "A circular specimen of MgO is loaded using a three-point bending mode. Compute the minimum possible radius of the specimen without fracture, given that the applied load is 425N\\left(95.5 lb \\mathrm{b}_{1}\\right), the flexural strength is 105 MPa(15,000 psi), and the separation between load points is 50 mm(2.0 in).", "answer": "the minimum possible radius of the specimen without fracture is 4.0mm (0.16 in).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解最小可能的半径，答案是一个具体的数值结果，解答过程需要运用材料力学中的三点弯曲公式进行计算。 | 知识层次: 题目需要进行多步计算，涉及弯曲强度的概念和三点弯曲模式的公式应用，需要综合分析给定的参数并正确运用公式来求解最小半径。虽然不涉及复杂的机理分析或创新设计，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及多步计算和概念关联，要求考生综合运用材料力学和强度计算的知识。虽然题目提供了所有必要参数，但需要正确应用三点弯曲公式并转换单位，属于综合性计算问题。", "convertible": true, "correct_option": "4.0mm (0.16 in)", "choice_question": "A circular specimen of MgO is loaded using a three-point bending mode. What is the minimum possible radius of the specimen without fracture, given that the applied load is 425N (95.5 lb), the flexural strength is 105 MPa (15,000 psi), and the separation between load points is 50 mm (2.0 in)?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.0 mm (0.16 in)", "B": "3.2 mm (0.13 in)", "C": "5.6 mm (0.22 in)", "D": "2.8 mm (0.11 in)" }, "correct_answer": "A", "explanation": "The correct answer is A (4.0 mm) calculated using the three-point bending formula for circular specimens: r = (8FL/πσ)^(1/3), where F=425N, L=50mm, σ=105MPa. Option B is a common miscalculation when forgetting to convert units consistently. Option C results from incorrectly using the diameter instead of radius in the calculation. Option D is a trap for those who confuse flexural strength with yield strength, leading to an underestimation of required radius.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 303, "question": "During the melt cooling and crystallization process, given the solid-liquid interface energy γ_sl=5×10^-6 J/cm^2 and the unit volume free energy change △Gv=2090 J/cm^3 at 900°C, calculate the critical nucleus radius.", "answer": "The critical nucleus radius r* = -2γ_sl/△Gv = -2×5×10^-6/2090 = 4.78×10^-10 m = 0.478 nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和数值进行具体计算，最终得出一个数值结果（临界核半径），符合计算题的特征。 | 知识层次: 题目涉及基本的公式应用和简单计算，直接套用临界核半径公式进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（临界核半径公式）进行简单计算，无需理解多个概念或进行复杂的分析。解题步骤非常直接，属于最基础的难度等级。", "convertible": true, "correct_option": "0.478 nm", "choice_question": "During the melt cooling and crystallization process, given the solid-liquid interface energy γ_sl=5×10^-6 J/cm^2 and the unit volume free energy change △Gv=2090 J/cm^3 at 900°C, what is the critical nucleus radius?", "conversion_reason": "The calculation question has a definite numerical answer, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.478 nm", "B": "4.78 nm", "C": "0.239 nm", "D": "2.39 nm" }, "correct_answer": "A", "explanation": "The critical nucleus radius (r*) is calculated using the formula r* = 2γ_sl/△Gv. Substituting the given values: r* = 2 × 5×10^-6 J/cm^2 / 2090 J/cm^3 = 4.78×10^-9 cm = 0.478 nm. Option B is a common unit conversion error (forgetting to convert cm to nm). Option C is half the correct value, a frequent mistake when misapplying the formula. Option D is an order-of-magnitude error combined with a factor of 2 mistake, representing a failure to properly account for both the formula and unit conversion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1005, "question": "Please analyze the characteristics and mechanisms of multiphase strengthening.", "answer": "Multiphase strengthening: When the relative content of the second phase is on the same order of magnitude as the matrix, strengthening occurs. The degree of strengthening depends on the quantity, size, distribution, and morphology of the second phase, and if the strength of the second phase is lower than that of the matrix, it may not contribute to strengthening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析多相强化的特性和机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析多相强化的特性和机制，涉及对多相材料中第二相的数量、尺寸、分布和形态等因素的综合分析，以及对强化机制的深入理解和解释。这需要较高的认知能力层次，包括分析、综合和推理，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题型中，该题目要求考生不仅理解多相强化的基本概念，还需要综合分析第二相的数量、尺寸、分布和形态对强化效果的影响，以及第二相强度与基体强度的相对关系。这涉及到多个因素的相互作用和机理的深度解释，属于复杂现象的全面分析，因此难度等级为5。", "convertible": true, "correct_option": "Multiphase strengthening: When the relative content of the second phase is on the same order of magnitude as the matrix, strengthening occurs. The degree of strengthening depends on the quantity, size, distribution, and morphology of the second phase, and if the strength of the second phase is lower than that of the matrix, it may not contribute to strengthening.", "choice_question": "Which of the following best describes the characteristics and mechanisms of multiphase strengthening?", "conversion_reason": "The answer is a standard explanation of the concept, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Multiphase strengthening: When the relative content of the second phase is on the same order of magnitude as the matrix, strengthening occurs. The degree of strengthening depends on the quantity, size, distribution, and morphology of the second phase, and if the strength of the second phase is lower than that of the matrix, it may not contribute to strengthening.", "B": "Multiphase strengthening occurs primarily through grain boundary pinning effects, where the second phase particles inhibit dislocation motion regardless of their relative strength compared to the matrix phase.", "C": "The effectiveness of multiphase strengthening is determined solely by the hardness difference between phases, with maximum strengthening achieved when the second phase is at least 50% harder than the matrix.", "D": "Multiphase systems strengthen materials through stress-induced transformation of the second phase, with strengthening proportional to the volume fraction of transformable phases present in the microstructure." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the comprehensive mechanism of multiphase strengthening, considering both phase content and mechanical property relationships. Option B incorrectly suggests grain boundary pinning is the primary mechanism, which is actually more characteristic of precipitation strengthening. Option C oversimplifies by focusing only on hardness difference, ignoring other critical factors like distribution and morphology. Option D describes transformation toughening, a specific phenomenon not generally applicable to all multiphase systems. These distractors exploit common misconceptions about strengthening mechanisms and oversimplifications of complex material behaviors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2595, "question": "When the crystal around an edge dislocation contains interstitial atoms below the equilibrium concentration, how will the dislocation climb?", "answer": "Positive climb", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释在特定条件下位错如何攀移，需要文字描述和论述，答案\"Positive climb\"是一个简短的定性描述，而非从多个选项中选择或简单判断对错。 | 知识层次: 题目涉及位错攀移机制与间隙原子浓度关系的深入分析，需要综合运用位错理论和扩散知识进行推理解释，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Positive climb", "choice_question": "When the crystal around an edge dislocation contains interstitial atoms below the equilibrium concentration, how will the dislocation climb?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Positive climb", "B": "Negative climb", "C": "No climb occurs", "D": "Lateral slip instead of climb" }, "correct_answer": "A", "explanation": "When interstitial atom concentration is below equilibrium, vacancies are effectively created, promoting positive climb as the dislocation absorbs vacancies. Option B is a reversal trap exploiting the 'below equilibrium' phrasing. Option C exploits the misconception that climb requires supersaturation. Option D triggers a common confusion between climb and slip mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2184, "question": "What effect does fibrous structure have on the properties of metals?", "answer": "Generally speaking, fibrous structure makes the longitudinal (fiber direction) strength of metals higher than the transverse strength. This is because on the cross-section, the cross-sectional area of brittle, low-strength 'components' such as impurities, second phases, and defects is small, while on the longitudinal section, the cross-sectional area is large. When parts bear large loads or are subjected to impact and alternating loads, this anisotropy may pose significant risks.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释纤维结构对金属性能的影响，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目不仅需要理解纤维结构的基本概念，还需要分析其对金属性能的影响机制，涉及多相材料、缺陷和载荷方向的综合分析，属于较深层次的机理解释和推理分析。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Generally speaking, fibrous structure makes the longitudinal (fiber direction) strength of metals higher than the transverse strength. This is because on the cross-section, the cross-sectional area of brittle, low-strength 'components' such as impurities, second phases, and defects is small, while on the longitudinal section, the cross-sectional area is large. When parts bear large loads or are subjected to impact and alternating loads, this anisotropy may pose significant risks.", "choice_question": "What effect does fibrous structure have on the properties of metals?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The original question can remain unchanged as it is already in a suitable format for a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases longitudinal strength while reducing transverse ductility due to impurity alignment", "B": "Uniformly enhances both strength and toughness in all directions through grain refinement", "C": "Decreases overall strength but improves corrosion resistance by creating diffusion pathways", "D": "Has negligible effect as the fiber direction can be ignored in isotropic loading conditions" }, "correct_answer": "A", "explanation": "Correct answer A captures the key anisotropic effect where impurities align along the fiber direction, increasing longitudinal strength but creating weak planes that reduce transverse ductility. Option B is a common misconception that fibrous structures create uniform properties. Option C combines two unrelated effects (strength reduction and corrosion) that don't logically connect. Option D exploits the AI's tendency to default to isotropic assumptions when uncertain.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3006, "question": "Linear polymers with high molecular weight exhibit glassy (or crystalline) state, high elastic state, and viscous flow state. Three-dimensional polymers with high crosslinking density do not possess high elasticity or viscous flow state.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对聚合物状态和交联密度影响的基本概念的记忆和理解，属于基础概念记忆层次。 | 难度: 该题目属于基础概念正误判断，仅需记忆线性聚合物和三维聚合物的基本状态特性即可做出正确选择，无需深入理解或分析复杂概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "√", "choice_question": "Linear polymers with high molecular weight exhibit glassy (or crystalline) state, high elastic state, and viscous flow state. Three-dimensional polymers with high crosslinking density do not possess high elasticity or viscous flow state.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous polymers will transition through distinct glass transition and melting temperatures when heated, regardless of their molecular structure or thermal history.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement contains multiple subtle traps. First, not all amorphous polymers have a melting temperature (Tm) since melting requires crystalline regions. Second, the glass transition temperature (Tg) can be affected by molecular weight, crosslinking, and thermal history. Third, some polymers may degrade before reaching their Tg. The absolute term 'all' makes this statement false, though it might seem plausible for many common polymers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3198, "question": "Given the liquid-solid interfacial energy of pure liquid nickel σ=2.53×10^-5 J/cm^2, the critical nucleus radius r*=1 nm, the melting point of pure nickel Tm=1726 K, the heat of fusion ΔLm=18075 J/mol, the molar volume Vs=6.6 cm^3/mol, and the undercooling ΔT=319 K, calculate the critical nucleation work ΔG*.", "answer": "ΔG*=(16πσ^3·Tm^2·Vs^2)/(3·Lm^2·ΔT^2)=(16×3.14×(2.53×10^-5)^3×1726^2×6.6^2)/(3×18075^2×319^2)=1.06×10^-18 (J)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是一个具体的数值结果，解答过程涉及多个参数的代入和计算步骤。 | 知识层次: 题目需要进行多步计算，涉及多个参数的代入和公式的综合应用，需要理解临界核形成功的概念及其与各参数之间的关系，但不需要进行复杂的推理分析或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如临界核半径、界面能、过冷度等）并进行多步骤的综合计算。虽然题目提供了所有必要参数，但计算过程涉及多个变量的组合和复杂公式的应用，要求考生具备较强的综合分析能力和计算准确性。", "convertible": true, "correct_option": "1.06×10^-18 (J)", "choice_question": "Given the liquid-solid interfacial energy of pure liquid nickel σ=2.53×10^-5 J/cm^2, the critical nucleus radius r*=1 nm, the melting point of pure nickel Tm=1726 K, the heat of fusion ΔLm=18075 J/mol, the molar volume Vs=6.6 cm^3/mol, and the undercooling ΔT=319 K, calculate the critical nucleation work ΔG*.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.06×10^-18 J", "B": "3.18×10^-18 J", "C": "5.30×10^-19 J", "D": "2.12×10^-18 J" }, "correct_answer": "A", "explanation": "The correct answer is A (1.06×10^-18 J) calculated using ΔG* = (16πσ³Tm²)/(3ΔLm²VsΔT²). Option B (3.18×10^-18 J) is a common error from incorrectly squaring the undercooling term. Option C (5.30×10^-19 J) results from forgetting to include the π term in the calculation. Option D (2.12×10^-18 J) comes from miscalculating the temperature ratio (Tm/ΔT) instead of (Tm/ΔT)².", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1783, "question": "Inverse spinel structure", "answer": "Inverse spinel structure: It belongs to the cubic crystal system, where oxygen ions can be considered to be arranged in a cubic close-packed structure. Divalent cations A occupy octahedral sites, while trivalent cations B are half-filled in octahedral sites and half-filled in tetrahedral sites.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Inverse spinel structure\"进行文字解释和论述，答案提供了详细的晶体结构描述，属于简答题类型。 | 知识层次: 题目考查对反尖晶石结构的基本定义和离子分布的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆反尖晶石结构的基本定义和组成，包括晶体系统、氧离子的排列方式以及不同价态阳离子的占位情况。虽然涉及多个知识点，但都属于基础概念记忆范畴，不需要复杂的分析或比较，因此难度适中。", "convertible": true, "correct_option": "Inverse spinel structure: It belongs to the cubic crystal system, where oxygen ions can be considered to be arranged in a cubic close-packed structure. Divalent cations A occupy octahedral sites, while trivalent cations B are half-filled in octahedral sites and half-filled in tetrahedral sites.", "choice_question": "下列关于Inverse spinel structure的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Inverse spinel structure: It belongs to the cubic crystal system, where oxygen ions can be considered to be arranged in a cubic close-packed structure. Divalent cations A occupy octahedral sites, while trivalent cations B are half-filled in octahedral sites and half-filled in tetrahedral sites.", "B": "Inverse spinel structure: It belongs to the hexagonal crystal system, where oxygen ions form a hexagonal close-packed arrangement. Trivalent cations B occupy all octahedral sites, while divalent cations A are distributed in tetrahedral sites.", "C": "Inverse spinel structure: It belongs to the cubic crystal system, where oxygen ions form a face-centered cubic arrangement. Divalent cations A occupy all tetrahedral sites, while trivalent cations B fill all octahedral sites.", "D": "Inverse spinel structure: It belongs to the tetragonal crystal system, where oxygen ions form a body-centered cubic arrangement. Divalent cations A and trivalent cations B are randomly distributed in both octahedral and tetrahedral sites." }, "correct_answer": "A", "explanation": "The correct answer is A because inverse spinel structure indeed belongs to the cubic crystal system with oxygen ions in cubic close-packed arrangement. The cation distribution is accurately described with divalent cations in octahedral sites and trivalent cations split between octahedral and tetrahedral sites. Option B is wrong by suggesting hexagonal system and incorrect cation distribution - this describes a normal spinel structure. Option C incorrectly states divalent cations occupy all tetrahedral sites, which is a common misconception. Option D introduces a completely wrong crystal system (tetragonal) and random cation distribution, exploiting the rare cases where some spinels can show tetragonal distortion at low temperatures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1179, "question": "The two basic types of dislocations are (22) and (23)", "answer": "(22) edge dislocation; (23) screw dislocation", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个基本类型的位错名称，需要提供具体的术语作为答案，属于简答题类型。 | 知识层次: 题目考查对位错基本类型的记忆和理解，属于材料科学中最基础的概念性知识 | 难度: 在选择题型中，该题目仅要求考生记忆并区分两种基本的位错类型（刃型位错和螺型位错），属于最基础的定义简答。题目仅涉及单一知识点的直接回忆，无需解释或复杂推理步骤，因此在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "edge dislocation and screw dislocation", "choice_question": "The two basic types of dislocations are:", "conversion_reason": "The answer is standard terminology and can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "edge dislocation and screw dislocation", "B": "linear dislocation and planar dislocation", "C": "elastic dislocation and plastic dislocation", "D": "primary dislocation and secondary dislocation" }, "correct_answer": "A", "explanation": "The correct answer is A because edge and screw dislocations are the two fundamental types of crystal defects defined by their Burgers vector orientation. Option B uses plausible-sounding spatial descriptors but doesn't reflect actual dislocation classification. Option C incorrectly suggests a mechanical response-based categorization, exploiting confusion between defect types and material behavior. Option D creates a false hierarchy that doesn't exist in dislocation theory, targeting AI's tendency to overgeneralize classification systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2271, "question": "For a φ5mm carbon steel sample with a carbon mass fraction of w_c=0.012, after quenching at 860°C and then tempering, how will the microstructure change during the tempering process?", "answer": "For carbon steel with w_c=0.012, when tempered below 100°C, carbon atoms form carbon-rich regions; during tempering at 100~200°C, a large number of fine carbides precipitate, resulting in a slight increase in hardness; during tempering at 200~300°C, retained austenite transforms into tempered martensite (or bainite), causing an increase in hardness, but at the same time, the hardness of martensite decreases, so overall, the hardness change is minimal; when tempered above 300°C, carbides continue to precipitate, followed by carbide growth and spheroidization, while the α phase undergoes recovery and recrystallization, leading to a decrease in hardness and an increase in toughness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求详细描述碳钢样品在回火过程中微观结构的变化过程，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析碳钢在回火过程中微观结构的变化，涉及多个温度阶段的相变和性能变化，需要综合运用材料科学中的相变理论、热处理原理和显微组织分析知识。解答过程需要对不同温度下的回火机制进行推理和解释，属于复杂分析和机理解释的范畴。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生对碳钢在回火过程中的微观组织变化有深入的理解，包括不同温度区间内的碳原子行为、碳化物析出、残余奥氏体转变以及α相的回复再结晶等复杂现象。解题需要综合运用材料科学中的相变理论、热处理原理和显微组织分析知识，进行多步骤的推理和机理解释。这种题目不仅考察知识点的记忆，更强调对复杂现象全面分析的能力，因此在选择题型中属于最高难度。", "convertible": true, "correct_option": "For carbon steel with w_c=0.012, when tempered below 100°C, carbon atoms form carbon-rich regions; during tempering at 100~200°C, a large number of fine carbides precipitate, resulting in a slight increase in hardness; during tempering at 200~300°C, retained austenite transforms into tempered martensite (or bainite), causing an increase in hardness, but at the same time, the hardness of martensite decreases, so overall, the hardness change is minimal; when tempered above 300°C, carbides continue to precipitate, followed by carbide growth and spheroidization, while the α phase undergoes recovery and recrystallization, leading to a decrease in hardness and an increase in toughness.", "choice_question": "For a φ5mm carbon steel sample with a carbon mass fraction of w_c=0.012, after quenching at 860°C and then tempering, which of the following describes how the microstructure changes during the tempering process?", "conversion_reason": "The answer is a detailed and standard description of the microstructure changes during the tempering process, which can be used as a correct option in a multiple-choice question. The question can be rephrased to ask for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "During tempering below 100°C, carbon atoms cluster forming carbon-rich regions without carbide precipitation", "B": "Between 100-200°C, ε-carbides precipitate causing significant hardness increase due to coherent strain fields", "C": "At 200-300°C, retained austenite transforms into fresh martensite rather than tempered martensite", "D": "Above 300°C, rapid carbide coarsening occurs while α-phase remains in highly dislocated state" }, "correct_answer": "A", "explanation": "Correct answer A describes the initial stage of tempering where carbon atoms cluster but don't form true carbides. Option B exaggerates the hardness increase at 100-200°C (only slight increase occurs). Option C incorrectly states fresh martensite formation (should be tempered martensite/bainite). Option D wrongly suggests the α-phase retains high dislocation density (actually undergoes recovery). These traps exploit common misconceptions about tempering stages and their effects on mechanical properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 304, "question": "During the melt cooling and crystallization process, given the solid-liquid interface energy γ_sl=5×10^-6 J/cm^2 and the unit volume free energy change △Gv=418 J/cm^3 at 1000°C, calculate the critical nucleus radius.", "answer": "The critical nucleus radius r* = -2γ_sl/△Gv = -2×5×10^-6/418 = 2.39×10^-9 m = 2.39 nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和数值进行计算，最终得出一个具体的数值结果（临界核半径），属于典型的计算题类型。 | 知识层次: 题目要求直接套用临界核半径公式进行计算，属于基本公式应用和简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（临界核半径公式）进行简单计算，无需理解多个概念或进行复杂分析。解题步骤非常直接，属于最基础的难度等级。", "convertible": true, "correct_option": "2.39 nm", "choice_question": "During the melt cooling and crystallization process, given the solid-liquid interface energy γ_sl=5×10^-6 J/cm^2 and the unit volume free energy change △Gv=418 J/cm^3 at 1000°C, the critical nucleus radius is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.39 nm", "B": "4.78 nm", "C": "1.20 nm", "D": "9.56 nm" }, "correct_answer": "A", "explanation": "正确答案A是通过临界核半径公式r* = 2γ_sl/△Gv计算得出。干扰项B是正确答案的两倍，利用了公式系数记忆错误的认知偏差；干扰项C是正确答案的一半，利用了常见计算错误模式；干扰项D是正确答案的四倍，利用了单位换算错误的直觉陷阱。所有干扰项都围绕常见计算错误模式设计，需要精确掌握公式和单位转换才能避免错误。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4062, "question": "[b] Aluminum is not very workable at high temperatures in air, in terms of extrusion and rolling, because a non-protective oxide grows and consumes the metal, converting it to a hard and brittle ceramic.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述，要求判断其正确性（答案F表示错误），符合判断题的特征。 | 知识层次: 题目考查对铝在高温下加工性能的基本概念记忆，涉及铝氧化物形成及其对加工性能影响的简单事实判断，属于基础概念记忆范畴。 | 难度: 该题目属于基础概念正误判断题，仅需记忆铝在高温下的氧化行为这一基本事实即可作答。在选择题型中属于最简单的难度等级，不涉及概念理解或复杂分析。", "convertible": true, "correct_option": "F", "choice_question": "[b] Aluminum is not very workable at high temperatures in air, in terms of extrusion and rolling, because a non-protective oxide grows and consumes the metal, converting it to a hard and brittle ceramic.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect brittleness with zero plastic deformation under any loading conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, some advanced ceramics can exhibit limited plastic deformation under specific conditions (e.g., high temperatures or hydrostatic pressure). The use of 'all' and 'any' makes this statement false, as it doesn't account for exceptions in advanced ceramics or special loading conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 218, "question": "Using Na2CO3 and Na2SiO3 to dilute the same type of clay slurry (mainly composed of kaolinite mineral), compare the differences in the casting rate of the two slurries when the same amount of electrolyte is added.", "answer": "The addition of Na2CO3 basically has no effect on the casting rate of the clay, while the addition of Na2SiO3 increases the casting rate of the slurry.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种电解质对粘土浆料浇注速率的影响，并给出解释。答案需要文字论述两种电解质的不同效果，而不是选择、判断或计算。 | 知识层次: 题目要求比较两种电解质对粘土浆料浇注速率的影响，涉及对电解质作用机理的理解和应用，需要综合分析不同电解质在粘土浆料中的行为差异，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解电解质对粘土浆料浇注速率的影响，并比较两种不同电解质（Na2CO3和Na2SiO3）的作用差异。题目要求考生综合分析两种电解质在相同条件下的不同效果，涉及多步概念关联和比较分析，但不需要进行复杂的多角度或深度关联性分析。", "convertible": true, "correct_option": "The addition of Na2CO3 basically has no effect on the casting rate of the clay, while the addition of Na2SiO3 increases the casting rate of the slurry.", "choice_question": "Using Na2CO3 and Na2SiO3 to dilute the same type of clay slurry (mainly composed of kaolinite mineral), what are the differences in the casting rate of the two slurries when the same amount of electrolyte is added?", "conversion_reason": "The answer is a clear and specific statement that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Na2CO3 increases casting rate more than Na2SiO3 due to stronger ionic dissociation", "B": "Both electrolytes decrease casting rate by compressing the double layer", "C": "Na2SiO3 increases casting rate while Na2CO3 has negligible effect", "D": "Both electrolytes increase casting rate equally by neutralizing surface charges" }, "correct_answer": "C", "explanation": "The correct answer is C because Na2SiO3 hydrolyzes to form colloidal silica which peptizes clay particles, increasing casting rate, while Na2CO3 only provides Na+ ions that minimally affect kaolinite's double layer. Option A exploits the common misconception about ionic strength effects. Option B reverses the actual behavior by suggesting both decrease rate. Option D creates false equivalence between the mechanisms of the two electrolytes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3696, "question": "Iron containing 0.05 % C is heated to 912 degrees C in an atmosphere that produces 1.20 % C at the surface and is held for 24 h. Calculate the carbon content at 0.05 cm beneath the surface if the iron is BCC.", "answer": "For BCC iron, the carbon content at 0.05 cm beneath the surface is 0.95 % C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算碳含量），并涉及公式应用（扩散方程等），答案是一个具体的数值结果（0.95 % C），符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及碳在BCC铁中的扩散问题，需要应用菲克第二定律等相关公式，并结合初始条件和边界条件进行综合分析。虽然不涉及复杂的机理分析或创新设计，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及碳在铁中的扩散计算，需要掌握菲克第二定律的应用，同时理解BCC结构对碳扩散的影响。解题步骤包括确定扩散系数、建立扩散方程并求解，属于多步骤计算过程。虽然题目提供了部分参数，但仍需综合分析才能得出正确选项。", "convertible": true, "correct_option": "0.95 % C", "choice_question": "Iron containing 0.05 % C is heated to 912 degrees C in an atmosphere that produces 1.20 % C at the surface and is held for 24 h. What is the carbon content at 0.05 cm beneath the surface if the iron is BCC?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.95 % C", "B": "1.20 % C", "C": "0.05 % C", "D": "0.60 % C" }, "correct_answer": "A", "explanation": "正确答案A基于Fick第二定律的扩散计算，考虑了BCC铁的扩散系数和时间-距离关系。干扰项B利用表面浓度直接作为答案的直觉陷阱；干扰项C利用初始浓度的认知偏差；干扰项D设计为接近但忽略扩散深度计算的专业直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 762, "question": "What are the characteristics of extrinsic diffusion?", "answer": "The activation energy of extrinsic diffusion only includes the energy of particle migration, and extrinsic diffusion dominates at low temperatures.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释外在扩散的特征，答案提供了文字解释和论述，符合简答题的特点。 | 知识层次: 题目考查的是外扩散（extrinsic diffusion）的基本特征，包括激活能的组成和温度影响，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并区分\"extrinsic diffusion\"的特征，包括激活能量的组成和温度影响。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。正确选项包含了两个关键特征，考生需要同时掌握这两个知识点才能正确作答。", "convertible": true, "correct_option": "The activation energy of extrinsic diffusion only includes the energy of particle migration, and extrinsic diffusion dominates at low temperatures.", "choice_question": "Which of the following describes the characteristics of extrinsic diffusion?", "conversion_reason": "The answer is a standard description of extrinsic diffusion, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy of extrinsic diffusion only includes the energy of particle migration, and extrinsic diffusion dominates at low temperatures.", "B": "Extrinsic diffusion has higher activation energy than intrinsic diffusion due to additional vacancy formation energy.", "C": "Extrinsic diffusion shows temperature-independent behavior because it is controlled by fixed impurity concentrations.", "D": "The diffusion coefficient for extrinsic diffusion follows an Arrhenius relationship with the same slope as intrinsic diffusion." }, "correct_answer": "A", "explanation": "Correct answer A states the key characteristics: extrinsic diffusion's activation energy only includes migration energy (since vacancies are already provided by impurities), and it dominates at low T where thermal vacancy concentration is low. B is wrong because it incorrectly includes vacancy formation energy. C is a trap - while impurity concentration is fixed, diffusion still depends on temperature through migration. D is misleading - while both follow Arrhenius behavior, extrinsic diffusion has a different slope (lower activation energy).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2001, "question": "What is the interface with the lowest interfacial energy?", "answer": "Coherent interface.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释哪种界面具有最低的界面能，答案需要文字解释和论述，而不是从选项中选择或简单的对错判断 | 知识层次: 题目考查对界面能基本概念的记忆和理解，特别是不同类型界面（如共格界面、半共格界面、非共格界面）的界面能高低比较。这属于基础概念的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"Coherent interface\"作为界面能最低的界面类型，属于基础概念的直接回忆。题目不涉及概念解释或复杂分析，仅需简单识别正确选项，因此属于最低难度等级。", "convertible": true, "correct_option": "Coherent interface", "choice_question": "Which of the following interfaces has the lowest interfacial energy?", "conversion_reason": "The answer is a standard term in materials science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Coherent interface between two single-crystal metals with identical lattice parameters", "B": "Semi-coherent interface between a metal and a ceramic with 5% lattice mismatch", "C": "Perfectly bonded amorphous-crystalline interface with no structural defects", "D": "Low-angle grain boundary (θ < 15°) in a pure metal with edge dislocations" }, "correct_answer": "A", "explanation": "The coherent interface (A) has the lowest energy because it maintains perfect atomic registry with no defects or strain. Option B is a semi-coherent interface which introduces misfit dislocations, increasing energy. Option C is a trap - while amorphous-crystalline interfaces can have low energy, they cannot achieve the perfect registry of coherent interfaces. Option D exploits the common misconception that low-angle grain boundaries are always lowest energy, but they still involve dislocation strain fields that coherent interfaces avoid.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3327, "question": "Describe the purpose of quenching", "answer": "Quenching can significantly improve the strength and hardness of steel. Combined with tempering at different temperatures, it can achieve a balance of strength, hardness, and toughness to meet various requirements.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求描述淬火的目的，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查淬火的基本目的及其对钢性能的影响，属于基础概念的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生不仅记忆淬火的基本定义，还需要理解淬火对钢材性能的影响以及与其他工艺（如回火）的协同作用。这超出了简单的定义记忆，属于概念解释和描述的层次，但不需要复杂的体系阐述或比较分析。", "convertible": true, "correct_option": "Quenching can significantly improve the strength and hardness of steel. Combined with tempering at different temperatures, it can achieve a balance of strength, hardness, and toughness to meet various requirements.", "choice_question": "What is the purpose of quenching?", "conversion_reason": "The answer is a standard explanation of the purpose of quenching, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To rapidly cool steel to form martensite and increase hardness", "B": "To slowly cool steel to relieve internal stresses and improve ductility", "C": "To heat steel above its recrystallization temperature for grain refinement", "D": "To maintain steel at constant temperature to achieve precipitation hardening" }, "correct_answer": "A", "explanation": "The correct answer is A because quenching involves rapid cooling to form martensite, a hard microstructure. Option B describes annealing, not quenching. Option C describes hot working processes, not quenching. Option D describes aging treatments for precipitation hardening alloys, which is unrelated to quenching.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 928, "question": "What are the characteristics of the space lattice in the cubic crystal system?", "answer": "The lattice parameters of the cubic crystal system are a=b=c, α=β=γ=90°.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释立方晶系的空间点阵特征，答案提供了文字描述而非选择、判断或计算。 | 知识层次: 题目考查立方晶系空间点阵的基本特征记忆，属于晶体学中最基础的概念性知识，仅需记忆晶格参数关系即可回答，不涉及应用或分析过程。 | 难度: 在选择题型中，该题目仅要求记忆立方晶系的基本定义（a=b=c，α=β=γ=90°），属于最基础的概念性知识，无需解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The lattice parameters of the cubic crystal system are a=b=c, α=β=γ=90°.", "choice_question": "Which of the following describes the characteristics of the space lattice in the cubic crystal system?", "conversion_reason": "The answer is a standard description of the cubic crystal system's lattice parameters, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The lattice parameters of the cubic crystal system are a=b=c, α=β=γ=90°", "B": "The lattice parameters satisfy a≠b≠c with α=β=γ=90°", "C": "The lattice parameters satisfy a=b≠c with α=β=90°, γ=120°", "D": "The lattice parameters satisfy a=b=c with α=β=γ≠90°" }, "correct_answer": "A", "explanation": "The cubic crystal system is defined by equal lattice parameters (a=b=c) and right angles (α=β=γ=90°). Option B describes an orthorhombic system, C describes a hexagonal system, and D describes a rhombohedral system. The trap in B exploits confusion between cubic and orthorhombic systems, C uses the common mistake of equating hexagonal close packing with cubic symmetry, while D plays on the misconception that equal parameters alone define cubic systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4800, "question": "A structural component is fabricated from an alloy that has a plane-strain fracture toughness of 62 MPa \\sqrt{m}. It has been determined that this component fails at a stress of 250 MPa when the maximum length of a surface crack is 1.6 mm. What is the maximum allowable surface crack length (in mm ) without fracture for this same component exposed to a stress of 250 MPa and made from another alloy that has a plane strain fracture toughness of 51 MPa \\sqrt{m} ?", "answer": "the maximum allowable surface crack length without fracture is 1.08 mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及平面应变断裂韧性和应力等参数的计算，最终要求得出最大允许表面裂纹长度的具体数值。答案也是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，涉及平面应变断裂韧性和应力强度因子的概念关联，需要综合分析不同合金的断裂韧性对最大允许表面裂纹长度的影响。虽然计算过程相对直接，但需要理解和应用相关公式，并进行适当的数值计算。 | 难度: 在选择题中属于中等难度，需要理解断裂韧性和应力强度因子的概念，并进行多步计算来求解最大允许裂纹长度。题目涉及多个变量的综合分析，但计算过程相对直接，属于综合性计算问题。", "convertible": true, "correct_option": "1.08 mm", "choice_question": "A structural component is fabricated from an alloy that has a plane-strain fracture toughness of 62 MPa √m. It has been determined that this component fails at a stress of 250 MPa when the maximum length of a surface crack is 1.6 mm. What is the maximum allowable surface crack length (in mm) without fracture for this same component exposed to a stress of 250 MPa and made from another alloy that has a plane strain fracture toughness of 51 MPa √m?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.08 mm", "B": "1.28 mm", "C": "0.96 mm", "D": "1.60 mm" }, "correct_answer": "A", "explanation": "正确答案A是通过断裂力学公式K_IC=Yσ√(πa)计算得出，其中K_IC比例变化导致裂纹长度平方反比变化。干扰项B利用常见计算错误(直接比例关系)，C利用单位换算陷阱(未考虑√m单位)，D是原始数据(未进行任何修正)的直觉陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 405, "question": "Kirkendall effect", "answer": "Kirkendall effect: A phenomenon in substitutional solid solutions where the relative diffusion of atoms of two components at different rates causes the migration of marker planes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对Kirkendall effect进行文字解释和论述，答案提供了详细的定义和现象描述，符合简答题的特征。 | 知识层次: 题目考查Kirkendall效应的基本定义和现象描述，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆Kirkendall效应的定义，即两种原子在置换固溶体中因扩散速率不同导致标记面迁移的现象。虽然需要掌握一定的专业术语和基本原理，但不需要进行复杂的分析或比较多个概念，因此属于中等难度。", "convertible": true, "correct_option": "Kirkendall effect: A phenomenon in substitutional solid solutions where the relative diffusion of atoms of two components at different rates causes the migration of marker planes.", "choice_question": "下列关于Kirkendall effect的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Kirkendall effect: A phenomenon in substitutional solid solutions where the relative diffusion of atoms of two components at different rates causes the migration of marker planes", "B": "Kirkendall effect: A phenomenon where vacancy diffusion dominates interstitial diffusion in FCC metals at high temperatures", "C": "Kirkendall effect: The preferential diffusion of smaller atoms through grain boundaries in polycrystalline materials", "D": "Kirkendall effect: The formation of voids due to equal but opposite diffusion fluxes in binary alloys" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the Kirkendall effect as the unequal diffusion rates in substitutional solid solutions causing marker plane movement. Option B incorrectly associates it with vacancy vs interstitial diffusion dominance. Option C describes grain boundary diffusion of smaller atoms, which is unrelated. Option D reverses the key aspect by suggesting equal diffusion fluxes, when the effect specifically requires unequal fluxes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 611, "question": "What is the carbon content of pearlite", "answer": "0.77%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求直接回答一个具体的数值（0.77%），不需要从多个选项中选择，也不需要判断对错或进行复杂的计算，属于简答题类型。 | 知识层次: 题目考查对珠光体碳含量的基本概念记忆，属于定义性知识的直接回忆，不涉及应用或分析过程。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即珠光体的碳含量这一具体数值。不需要解释或分析，只需直接回忆并选择正确选项0.77%。属于最基础的定义简答级别。", "convertible": true, "correct_option": "0.77%", "choice_question": "What is the carbon content of pearlite?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.77%", "B": "0.83%", "C": "0.67%", "D": "2.11%" }, "correct_answer": "A", "explanation": "Pearlite is a lamellar structure of ferrite and cementite with a fixed carbon content of 0.77%. Option B (0.83%) exploits the proximity bias by using the eutectoid temperature (727°C) in a misleading way. Option C (0.67%) creates confusion with the lower critical temperature where pearlite starts forming. Option D (2.11%) is the maximum solubility of carbon in austenite, deliberately using a fundamental but irrelevant phase diagram value.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 162, "question": "Among the following three substances, which one is the least likely to form glass, and why? (1) Na2O·2SiO2; (2) Na2O·SiO2; (3) NaCl", "answer": "(3) NaCl is the least likely to form glass. NaCl lacks a network structure and is a typical ionic crystal, making it difficult to form glass.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从三个选项中选择最不可能形成玻璃的物质，并解释原因，符合选择题的特征 | 知识层次: 题目要求考生理解玻璃形成的基本原理（网络结构），并能够分析不同物质的化学组成和结构特点（离子晶体vs硅酸盐），从而判断其形成玻璃的能力。这需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，需要综合应用多个概念进行分析判断。题目要求考生不仅了解玻璃形成的基本原理（网络结构的重要性），还需要比较三种不同物质的结构特性（硅酸盐网络结构 vs 离子晶体结构），并做出正确判断。解题过程涉及材料科学中玻璃形成能力的核心概念，需要将晶体结构知识与玻璃形成条件进行关联分析，属于复杂分析过程的判断题型。", "convertible": true, "correct_option": "(3) NaCl", "choice_question": "Among the following three substances, which one is the least likely to form glass?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer is a specific option from the given choices. It can be directly converted to a single-choice question by removing the explanation in the answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Na2O·2SiO2", "B": "Na2O·SiO2", "C": "NaCl", "D": "All three substances have equal glass-forming ability" }, "correct_answer": "C", "explanation": "The correct answer is NaCl because it is an ionic compound with high crystallization tendency and lacks the network-forming structural units needed for glass formation. Na2O·2SiO2 (A) and Na2O·SiO2 (B) are classic glass-forming silicates with appropriate viscosity-temperature behavior. Option D is a cognitive bias trap exploiting the common misconception that all oxide systems can form glass equally. The question specifically targets AI's potential confusion between glass-forming silicates and non-glass-forming ionic salts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1316, "question": "What is the main phenomenon during the low-temperature recovery of cold-worked metals?", "answer": "The disappearance of point defects", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释低温恢复冷加工金属的主要现象，答案需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查对冷加工金属低温回复过程中主要现象的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念记忆层次，仅需回忆低温恢复过程中点缺陷消失这一基本现象。选择题型中仅需识别正确选项，无需解释或分析，属于最简单的定义识别类题目。", "convertible": true, "correct_option": "The disappearance of point defects", "choice_question": "What is the main phenomenon during the low-temperature recovery of cold-worked metals?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Annihilation of excess vacancies through diffusion to grain boundaries", "B": "Rearrangement of dislocations into low-energy configurations", "C": "Partial recrystallization of deformed grains", "D": "Precipitation of secondary phases at defect sites" }, "correct_answer": "A", "explanation": "The correct answer is A because low-temperature recovery primarily involves point defect migration, particularly vacancy diffusion to sinks like grain boundaries. Option B describes a higher-temperature recovery process, creating a temperature-scale confusion trap. Option C introduces recrystallization which doesn't occur at low temperatures, exploiting a common process confusion. Option D presents a plausible-sounding but irrelevant phenomenon, targeting AI's tendency to associate defects with precipitation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2651, "question": "Given that pure titanium at 900°C is β-Ti (bcc structure) with a lattice constant a=0.3307nm, calculate the (001) interplanar spacing.", "answer": "For the (001) plane of bcc structure, d_(001)=1/2×a/√1²=1/2×0.3307/1=0.1653nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算(001)晶面间距），并应用了晶体学公式（d_(001)=a/√(h²+k²+l²)），答案是一个具体的计算结果（0.1653nm）。这符合计算题的特征。 | 知识层次: 题目主要考查基本公式的直接应用和简单计算，涉及晶体学中晶面间距的计算，属于基础知识的直接运用，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算，即d_(001)=1/2×a/√1²，无需额外的概念理解或步骤组合。属于最基础的难度等级。", "convertible": true, "correct_option": "0.1653nm", "choice_question": "Given that pure titanium at 900°C is β-Ti (bcc structure) with a lattice constant a=0.3307nm, what is the (001) interplanar spacing?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1653nm", "B": "0.3307nm", "C": "0.2339nm", "D": "0.2867nm" }, "correct_answer": "A", "explanation": "For a bcc structure, the (001) interplanar spacing is simply half the lattice constant (a/2=0.3307/2=0.1653nm). Option B is the lattice constant itself, a common mistake when forgetting to divide by 2. Option C is calculated incorrectly as a/sqrt(2), which applies to (110) planes. Option D is a/sqrt(3), which applies to (111) planes. These incorrect options exploit the tendency to confuse interplanar spacing formulas for different crystallographic planes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1789, "question": "The defect concentration of the non-stoichiometric compound Zn1+xO is related to the nature and partial pressure of the surrounding atmosphere. When the oxygen partial pressure is increased, explain through calculation what changes will occur in the density of Zn1+xO.", "answer": "ZnO↔Zni+2e'+1/2O2; Zn1+xO; the concentration of zinc interstitial ions is inversely proportional to the oxygen partial pressure. When the oxygen partial pressure increases, the x value in Zn1+xO decreases, resulting in a reduction of its density.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过计算解释Zn1+xO密度的变化，答案提供了详细的文字解释和化学反应方程式，但没有涉及具体的数值计算步骤，更侧重于概念和原理的论述。 | 知识层次: 题目需要理解非化学计量化合物Zn1+xO的缺陷浓度与周围气氛的关系，并通过化学反应方程式和浓度关系进行计算分析。这涉及到多步计算和概念关联，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅理解非化学计量化合物Zn1+xO的缺陷浓度与周围气氛的关系，还需要通过计算分析氧分压变化对密度的影响。正确选项涉及多个概念（缺陷反应、浓度关系、密度变化）的综合分析，并需要将理论知识与实际计算相结合。这种多步骤、多角度的分析在选择题型中较为复杂，对考生的知识掌握深度和综合分析能力要求较高。", "convertible": true, "correct_option": "the concentration of zinc interstitial ions is inversely proportional to the oxygen partial pressure. When the oxygen partial pressure increases, the x value in Zn1+xO decreases, resulting in a reduction of its density.", "choice_question": "When the oxygen partial pressure is increased, what changes will occur in the density of Zn1+xO?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The density decreases due to reduction of zinc interstitial defects", "B": "The density increases as oxygen vacancies are filled by additional oxygen", "C": "The density remains constant because ZnO is a stoichiometric compound", "D": "The density first increases then decreases due to competing defect mechanisms" }, "correct_answer": "A", "explanation": "The correct answer is A because increasing oxygen partial pressure reduces zinc interstitial concentration (x decreases in Zn1+xO), lowering density. B is incorrect because it confuses the dominant defect type (zinc interstitials, not oxygen vacancies). C is wrong by falsely assuming stoichiometry. D creates a false complexity by suggesting non-existent competing mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4276, "question": "Do all metals have the same slip system? Why or why not?", "answer": "All metals do not have the same slip system. The reason for this is that for most metals, the slip system will consist of the most densely packed crystallographic plane, and within that plane the most closely packed direction. This plane and direction will vary from crystal structure to crystal structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么所有金属的滑移系统不相同，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目不仅需要理解金属滑移系统的基本概念，还需要分析不同晶体结构对滑移系统的影响，涉及多步概念关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解金属的滑移系统概念，并能够分析不同晶体结构对滑移系统的影响。题目要求考生将晶体结构的紧密堆积面与方向的概念关联起来，并进行综合比较分析。虽然不需要多角度论述或深度关联性分析，但仍需一定的概念理解和应用能力。", "convertible": true, "correct_option": "All metals do not have the same slip system. The reason for this is that for most metals, the slip system will consist of the most densely packed crystallographic plane, and within that plane the most closely packed direction. This plane and direction will vary from crystal structure to crystal structure.", "choice_question": "Do all metals have the same slip system? Why or why not?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice scenario by providing the correct explanation as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because slip systems are determined by crystal structure which varies between metals", "B": "Yes, because all metals share the same FCC crystal structure", "C": "No, because slip systems are determined by electron configuration rather than crystal structure", "D": "Yes, because dislocation movement follows the same principles in all metals" }, "correct_answer": "A", "explanation": "The correct answer is A because slip systems are indeed determined by crystal structure, which varies between metals (FCC, BCC, HCP etc.). Option B is incorrect because not all metals have FCC structure. Option C is a cognitive bias trap - while electron configuration affects bonding, it doesn't directly determine slip systems. Option D exploits oversimplification by suggesting universal dislocation behavior regardless of crystal structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3492, "question": "How to improve the corrosion resistance of steel?", "answer": "Methods to improve the corrosion resistance of steel: (a) Increase the electrode potential of the metal. (b) Make the metal easier to passivate. (c) Obtain a single-phase structure with uniform chemical composition, microstructure, and metal purity, aiming to avoid the formation of microcells.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释如何提高钢的耐腐蚀性，答案提供了详细的文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目要求对提高钢材耐腐蚀性的方法进行解释和论述，涉及多个概念（电极电位、钝化、单相结构等）的关联和综合分析，需要一定的理解和应用能力，但不需要复杂的创新或深度设计。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握提高钢材耐腐蚀性的多种方法，并能够区分不同方法的原理和效果。正确选项涉及电极电位、钝化现象以及微观结构等概念，需要考生具备一定的综合分析能力。虽然题目提供了具体选项，但需要对材料科学中的腐蚀防护有较深入的理解才能准确选择最佳答案。", "convertible": true, "correct_option": "Methods to improve the corrosion resistance of steel: (a) Increase the electrode potential of the metal. (b) Make the metal easier to passivate. (c) Obtain a single-phase structure with uniform chemical composition, microstructure, and metal purity, aiming to avoid the formation of microcells.", "choice_question": "Which of the following methods can improve the corrosion resistance of steel?", "conversion_reason": "The answer provided is a standard and concise explanation of methods to improve corrosion resistance of steel, which can be formatted into a multiple-choice question with the given answer as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Adding 13% chromium to form a passive oxide layer", "B": "Increasing the carbon content to enhance hardness", "C": "Introducing sulfur to form protective sulfide films", "D": "Reducing grain size through severe plastic deformation" }, "correct_answer": "A", "explanation": "Correct answer A utilizes chromium's well-documented passivation effect. Distractors employ: B - hardness/corrosion resistance confusion (cognitive bias), C - plausible but incorrect sulfide protection (professional intuition trap), D - grain refinement benefits misapplied to corrosion (multi-level verification trap where grain boundaries actually increase corrosion sites).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1980, "question": "Determine whether the following dislocation reaction can occur: $\\\\frac{a}{3}[112]+\\\\frac{a}{2}[111]\\\\rightarrow\\\\frac{a}{6}[11\\\\overline{{{1}}}]$", "answer": "No. Geometric condition: $\\\\sum b_{\\\\mathbb{H}}=\\\\frac{a}{b}[557],\\\\sum b_{\\\\mathbb{H}}=\\\\frac{a}{b}[11\\\\overline{{1}}]$, cannot be satisfied.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断位错反应是否能够发生，答案直接给出了\"否\"的判断结果，并提供了几何条件的验证依据。这符合判断题的特征，即对陈述或命题进行真伪判断。 | 知识层次: 题目需要应用位错反应的基本原理进行几何条件的判断，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目要求判断位错反应是否能够发生，这需要理解位错反应的几何条件和能量条件。其次，解题过程涉及多步计算和概念关联，包括位错矢量的计算和比较。最后，题目要求综合分析计算结果来判断反应是否满足条件，这超出了简单的概念记忆或单一计算步骤，属于中等应用层次的知识要求。因此，在选择题型内，该题目属于等级4的难度。", "convertible": true, "correct_option": "No. Geometric condition: $\\\\sum b_{\\\\mathbb{H}}=\\\\frac{a}{b}[557],\\\\sum b_{\\\\mathbb{H}}=\\\\frac{a}{b}[11\\\\overline{{1}}]$, cannot be satisfied.", "choice_question": "Determine whether the following dislocation reaction can occur: $\\\\frac{a}{3}[112]+\\\\frac{a}{2}[111]\\\\rightarrow\\\\frac{a}{6}[11\\\\overline{{{1}}}]$", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All dislocation reactions in face-centered cubic metals must satisfy both the geometric condition and the energy condition to occur.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most dislocation reactions require both conditions, there are exceptional cases where reactions may occur under specific stress conditions even if the geometric condition is not perfectly satisfied. The absolute term 'all' makes this statement false.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2030, "question": "What are the types of silicate structures", "answer": "Silicates are divided into the following categories: (1) silicates containing finite silicon-oxygen groups; (2) chain silicates; (3) layer silicates; (4) framework silicates.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和列举硅酸盐结构的类型，答案以文字形式详细描述了不同类型的硅酸盐结构，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对硅酸盐结构分类的基本概念记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确记忆并区分四种不同的硅酸盐结构类型。这比单纯记忆一个定义（等级1）要求更高，但不需要进行复杂的分析或阐述（等级3）。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "Silicates are divided into the following categories: (1) silicates containing finite silicon-oxygen groups; (2) chain silicates; (3) layer silicates; (4) framework silicates.", "choice_question": "Which of the following correctly describes the types of silicate structures?", "conversion_reason": "The answer is a standard classification of silicate structures, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Silicates are divided into the following categories: (1) silicates containing finite silicon-oxygen groups; (2) chain silicates; (3) layer silicates; (4) framework silicates", "B": "Silicates are classified as: (1) isolated tetrahedra; (2) single chains; (3) double chains; (4) sheets; (5) frameworks", "C": "The main silicate structures are: (1) orthosilicates; (2) pyrosilicates; (3) cyclic silicates; (4) inosilicates; (5) phyllosilicates; (6) tectosilicates", "D": "Silicates can be categorized as: (1) monomeric; (2) dimeric; (3) oligomeric; (4) polymeric" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely follows the standard classification of silicate structures based on their connectivity. Option B is incorrect because it mixes structural classification (single/double chains) with dimensional classification. Option C is incorrect as it uses outdated terminology (orthosilicates, pyrosilicates) that doesn't fully represent modern structural classification. Option D is incorrect as it applies polymer chemistry terminology which is inappropriate for silicate classification. The difficulty lies in distinguishing between historically used terms (Option C) and modern structural classification (Option A), which requires deep knowledge of silicate chemistry evolution.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3330, "question": "After quenching T8 steel wire to 275°C and holding for 1s, indicate its phase and composition.", "answer": "Undercooled austenite (w_C=0.77%)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述材料的相和组成，需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目需要理解T8钢的相变行为，并应用TTT图或CCT图的知识来确定在特定温度和时间下的相组成。这涉及到多步的概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及T8钢的淬火工艺、相变温度以及相组成等知识点，要求考生能够综合运用这些知识来判断在特定条件下的相和成分。虽然题目给出了具体的温度和时间条件，但需要考生对钢的相变行为和成分有深入的理解才能正确选择答案。此外，题目还要求考生能够将理论知识与实际工艺条件相结合，进行综合分析。", "convertible": true, "correct_option": "Undercooled austenite (w_C=0.77%)", "choice_question": "After quenching T8 steel wire to 275°C and holding for 1s, what is its phase and composition?", "conversion_reason": "The answer is a standard term and can be converted into a multiple-choice format by providing options including the correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Undercooled austenite (w_C=0.77%)", "B": "Martensite (w_C=0.8%)", "C": "Bainite (w_C=0.77%)", "D": "Pearlite (w_C=0.8%)" }, "correct_answer": "A", "explanation": "The correct answer is A because at 275°C with a 1s hold, T8 steel (eutectoid composition) would remain as undercooled austenite before transformation begins. Option B exploits the common misconception that quenching always produces martensite, ignoring the temperature and time conditions. Option C uses the correct carbon content but incorrectly suggests bainite formation would occur instantaneously. Option D leverages the pearlite misconception from slow cooling scenarios, with a slight carbon content deviation to create doubt.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1883, "question": "What is a space group?", "answer": "The collection of all symmetry elements in a crystal structure", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"space group\"进行定义和解释，答案是一个简短的文字描述，符合简答题的特征 | 知识层次: 题目考查对空间群这一基本概念的定义记忆和理解，属于晶体学中的基础概念，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对\"space group\"这一基础概念的定义记忆，属于最基础的知识点。正确选项直接给出了术语的标准定义，不需要任何解释、比较或分析过程，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The collection of all symmetry elements in a crystal structure", "choice_question": "What is a space group?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The collection of all symmetry elements in a crystal structure", "B": "A group of atomic positions related by translational symmetry only", "C": "The set of all possible crystallographic planes in a lattice", "D": "A mathematical description of electron density distribution in a unit cell" }, "correct_answer": "A", "explanation": "The correct answer is A because a space group comprehensively describes all symmetry operations (including rotations, reflections, translations, and their combinations) that leave the crystal structure invariant. Option B is incorrect because it omits other symmetry elements like rotations and reflections. Option C describes crystallographic planes, not symmetry operations. Option D refers to Fourier transform of electron density, which is unrelated to symmetry operations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 314, "question": "What is the (100) interplanar spacing of a face-centered cubic metal? (a is the lattice constant)", "answer": "The interplanar spacing d=a/2", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算面心立方金属的(100)晶面间距，需要使用公式d=a/2进行计算，属于需要数值计算和公式应用的题目。 | 知识层次: 题目考查基本公式应用和简单计算，仅需套用面心立方晶体的晶面间距公式d=a/√(h²+k²+l²)，代入(100)面的hkl值即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用基本公式（d=a/2）进行计算，无需额外的推导或组合多个公式。知识层次为简单应用，属于最基础的难度等级。", "convertible": true, "correct_option": "d=a/2", "choice_question": "What is the (100) interplanar spacing of a face-centered cubic metal? (a is the lattice constant)", "conversion_reason": "The answer is a specific and deterministic value, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "d=a/2", "B": "d=a/√2", "C": "d=a/√3", "D": "d=a" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC crystals, the (100) planes are not the closest-packed planes. The interplanar spacing for (100) is simply half the lattice constant (a/2). Option B is a trap for those confusing with the (110) plane spacing (a/√2). Option C exploits confusion with the (111) plane spacing (a/√3). Option D is designed to catch those who forget to divide by the Miller index.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3487, "question": "What is the role of carbon in high-speed steel?", "answer": "The role of carbon in high-speed steel: high carbon content, generally with a mass fraction of 0.7% to 1.5%, is to ensure the formation of alloy carbides with alloying elements, obtaining a martensite matrix plus carbides during quenching to improve the hardness and wear resistance of the steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释碳在高速钢中的作用，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释碳在高速钢中的作用，涉及碳含量范围、合金碳化物的形成、马氏体基体与碳化物的相互作用等概念关联和综合分析，需要理解并应用材料科学中的合金化原理和相变知识，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解碳在高速钢中的作用机制，包括碳含量范围、合金碳化物的形成、马氏体基体的获得以及硬度和耐磨性的提升等多个概念，并进行综合分析。虽然不需要多角度分析论述或深度关联性分析，但仍需一定的知识掌握和概念关联能力。", "convertible": true, "correct_option": "High carbon content, generally with a mass fraction of 0.7% to 1.5%, is to ensure the formation of alloy carbides with alloying elements, obtaining a martensite matrix plus carbides during quenching to improve the hardness and wear resistance of the steel.", "choice_question": "What is the role of carbon in high-speed steel?", "conversion_reason": "The answer is a standard explanation of the role of carbon in high-speed steel, which can be directly used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Forms alloy carbides to enhance hardness and wear resistance through martensitic transformation", "B": "Primarily increases the steel's ductility by stabilizing austenite at room temperature", "C": "Acts as a grain refiner to improve toughness by reducing prior austenite grain size", "D": "Enhances corrosion resistance by forming passive chromium carbide layers" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual role of carbon in forming hard alloy carbides and enabling martensite formation during quenching. Option B exploits the common misconception about austenite stabilization (relevant for stainless steels but not high-speed steels). Option C uses the grain refinement concept (valid for some alloys but not the primary carbon function here). Option D introduces corrosion resistance (a chromium effect, misleadingly attributing it to carbon).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4203, "question": "What type(s) of bonding would be expected for bronze?", "answer": "For bronze, the bonding is metallic since it is a metal alloy (composed of copper and tin).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释青铜中预期的键合类型，答案需要文字论述和解释，而不是从选项中选择或判断对错。 | 知识层次: 题目考查对金属合金（青铜）基本键合类型的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即青铜（bronze）作为金属合金的键合类型。不需要解释或分析，只需识别并选择正确的定义性描述。这属于最基础的知识层次要求，解题步骤简单直接。", "convertible": true, "correct_option": "metallic", "choice_question": "What type of bonding would be expected for bronze?", "conversion_reason": "The answer is a standard term (metallic) and can be presented as a single correct option among other plausible bonding types.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metallic", "B": "Ionic", "C": "Covalent", "D": "Mixed metallic-covalent" }, "correct_answer": "A", "explanation": "Bronze is an alloy primarily composed of copper and tin, exhibiting metallic bonding due to the delocalized electrons in the metal lattice. Option B (Ionic) is incorrect as bronze lacks the electron transfer characteristic of ionic compounds. Option C (Covalent) is a trap for those considering the alloying elements' individual properties, but bronze does not form directional covalent bonds. Option D (Mixed metallic-covalent) exploits the common misconception that alloying introduces covalent character, but bronze's properties are dominated by metallic bonding.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4481, "question": "Compute the repeat unit molecular weight of polystyrene.", "answer": "the repeat unit molecular weight of polystyrene is 104.14 g/mol.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算聚苯乙烯的重复单元分子量，需要应用化学公式和数值计算，答案是一个具体的数值结果。 | 知识层次: 题目要求计算聚苯乙烯重复单元的分子量，这需要应用基本的化学计算和分子量公式，属于直接套用基本知识的简单应用。 | 难度: 在选择题型中，该题目仅需要直接套用已知的重复单元分子量公式进行计算，无需额外的公式组合或复杂步骤。属于单一公式直接计算的简单应用层次，因此难度等级为1。", "convertible": true, "correct_option": "104.14 g/mol", "choice_question": "What is the repeat unit molecular weight of polystyrene?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "104.14 g/mol", "B": "108.14 g/mol", "C": "100.00 g/mol", "D": "96.00 g/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (104.14 g/mol) because the repeat unit of polystyrene consists of one styrene monomer (C8H8), with a molecular weight of 104.14 g/mol. Option B (108.14 g/mol) is a cognitive bias trap that adds the hydrogen atom from polymerization initiation. Option C (100.00 g/mol) exploits the tendency to round molecular weights. Option D (96.00 g/mol) is a professional intuition trap based on incorrectly counting only the carbon atoms in the aromatic ring.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4435, "question": "(a) Suppose that Li2O is added as an impurity to CaO. If the Li+ substitutes for Ca2+, what kind of vacancies would you expect to form? How many of these vacancies are created for every Li+ added?", "answer": "oxygen vacancies. Two Li+ ions added, a single oxygen vacancy is formed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要解释Li+取代Ca2+时形成的空位类型，并说明每添加一个Li+离子会形成多少个空位。答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要理解离子替代对晶体缺陷的影响，并分析Li+替代Ca2+时电荷平衡的机制，涉及多步推理和概念关联。虽然不涉及复杂计算，但需要综合分析电荷补偿和缺陷形成的原理。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及杂质掺杂和空位形成机制，要求考生掌握离子取代对晶体缺陷的影响，并能进行简单的电荷平衡计算。虽然解题步骤较为明确（Li+取代Ca2+会导致氧空位形成，且每两个Li+产生一个氧空位），但需要将晶体缺陷化学与电荷补偿原理结合起来分析，属于中等应用层次的知识运用。", "convertible": true, "correct_option": "oxygen vacancies. Two Li+ ions added, a single oxygen vacancy is formed.", "choice_question": "Suppose that Li2O is added as an impurity to CaO. If the Li+ substitutes for Ca2+, what kind of vacancies would you expect to form and how many of these vacancies are created for every Li+ added?", "conversion_reason": "The answer is a standard terminology and concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Oxygen vacancies; one vacancy per two Li+ ions", "B": "Calcium vacancies; one vacancy per Li+ ion", "C": "Oxygen interstitials; two interstitials per Li+ ion", "D": "Lithium vacancies; one vacancy per Li+ ion" }, "correct_answer": "A", "explanation": "The correct answer is A because when Li+ (1+) substitutes for Ca2+ (2+), it creates a net negative charge that must be compensated by forming oxygen vacancies. Two Li+ ions are needed to balance the charge of one missing Ca2+, creating one oxygen vacancy. Option B is incorrect because it suggests the wrong type of vacancy and incorrect stoichiometry. Option C is wrong because it proposes oxygen interstitials instead of vacancies, which would exacerbate the charge imbalance. Option D is misleading as it suggests lithium vacancies, which doesn't address the charge compensation mechanism in this substitution scenario.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 857, "question": "When an aluminum (Al) single crystal is stretched along the [123] direction to induce plastic deformation, determine the rotation law and rotation axis of the crystal during double slip.", "answer": "During double slip, the specimen axis rotates toward [101], with the rotation axis being n1=[11¯2]×[10¯1]=[¯1¯1¯1], and also rotates toward [011], with the rotation axis being n2=[11¯2]×[01¯1]=[111]. Therefore, the resultant rotation axis is n=n1+ n2=[000], meaning the crystal orientation no longer changes and is only elongated.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释晶体在双滑移过程中的旋转规律和旋转轴，答案提供了详细的文字解释和论述，没有涉及选择、判断或数值计算。 | 知识层次: 题目要求分析铝单晶在双滑移过程中的旋转规律和旋转轴，涉及晶体塑性变形机制的综合理解和推理分析。需要综合运用晶体学、滑移系选择、旋转轴计算等知识，并进行多步推理和解释，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求综合运用晶体塑性变形、双滑移机制、晶体旋转定律等复杂概念，并进行矢量运算和空间几何分析。解题步骤涉及多个高阶知识点的整合，包括确定滑移方向、计算旋转轴、理解双滑移条件下的合成效应等。正确选项的推导需要深入理解晶体力学行为并具备较强的空间推理能力，远超一般选择题的认知要求。", "convertible": true, "correct_option": "During double slip, the specimen axis rotates toward [101], with the rotation axis being n1=[11¯2]×[10¯1]=[¯1¯1¯1], and also rotates toward [011], with the rotation axis being n2=[11¯2]×[01¯1]=[111]. Therefore, the resultant rotation axis is n=n1+ n2=[000], meaning the crystal orientation no longer changes and is only elongated.", "choice_question": "When an aluminum (Al) single crystal is stretched along the [123] direction to induce plastic deformation, what is the rotation law and rotation axis of the crystal during double slip?", "conversion_reason": "The answer is a standard and specific description of the rotation law and rotation axis during double slip, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The crystal rotates toward [101] with axis [¯1¯1¯1], and toward [011] with axis [111], resulting in zero net rotation", "B": "The crystal rotates toward [112] with axis [1¯10], following Schmid's law for single slip systems", "C": "The crystal maintains fixed orientation while elongating, with rotation axis parallel to [123]", "D": "The crystal rotates toward [111] with axis [1¯10], as this is the closest <110> direction to the tensile axis" }, "correct_answer": "A", "explanation": "Correct answer A accounts for the complex double slip condition where two competing rotation axes cancel out. B incorrectly applies single slip behavior. C is a common oversimplification trap ignoring crystallographic rotation. D uses a plausible but incorrect closest-direction heuristic, exploiting AI's tendency toward geometric pattern matching.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4937, "question": "Zinc selenide has a band gap of 2.58 eV. Over what range of wavelengths of visible light is it transparent?", "answer": "pure znse is transparent to visible light having wavelengths between 0.48 and 0.7 \\mu m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要根据给定的能带隙值（2.58 eV）计算对应的波长范围，涉及公式应用和数值计算。答案给出了具体的计算结果（0.48到0.7微米），表明这是一个需要计算步骤的问题。 | 知识层次: 题目需要应用基本的公式（如能隙与波长的关系公式）进行简单计算，属于直接套用基本公式的应用层次，不需要多步计算或综合分析。 | 难度: 在选择题中属于简单难度，需要应用基本公式（波长与能量的转换公式）进行简单计算，但不需要多个公式组合或复杂分析。", "convertible": true, "correct_option": "pure znse is transparent to visible light having wavelengths between 0.48 and 0.7 μm", "choice_question": "Zinc selenide has a band gap of 2.58 eV. Over what range of wavelengths of visible light is it transparent?", "conversion_reason": "The answer is a specific range of wavelengths, which can be presented as a distinct option among other plausible but incorrect ranges.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.48-0.70 μm (transparent to all visible light)", "B": "0.38-0.48 μm (only transparent to violet/blue light)", "C": "0.70-0.90 μm (only transparent to near-infrared light)", "D": "0.30-0.70 μm (transparent to UV and visible light)" }, "correct_answer": "A", "explanation": "The correct answer is A because ZnSe's band gap of 2.58 eV corresponds to a cutoff wavelength of ~480 nm (calculated by λ=hc/Eg). This means it absorbs all light with wavelengths shorter than 480 nm (higher energy than band gap), making it transparent only to visible light between 480-700 nm. Option B is a cognitive bias trap - it reverses the absorption logic. Option C exploits infrared transparency intuition from other semiconductors. Option D is a multi-level trap combining correct visible range with incorrect UV transparency.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3212, "question": "A 20m long aluminum rod with a diameter of 14.0mm is drawn through a die with an aperture of 12.7mm. Calculate the engineering linear strain experienced by this aluminum rod.", "answer": "The engineering strain ε=(L-L0)/L0=21.5%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算工程线性应变），需要应用公式ε=(L-L0)/L0，并最终给出数值结果21.5%，符合计算题的特征。 | 知识层次: 题目考查基本公式（工程应变公式）的直接应用和简单计算，不需要多步推导或综合分析 | 难度: 在选择题型中，该题目仅需要直接应用工程应变的基本公式 ε=(L-L0)/L0 进行计算，无需额外的公式组合或复杂推导。题目提供了所有必要的参数（初始长度和直径变化），计算步骤简单直接，属于单一公式直接计算的难度等级。", "convertible": true, "correct_option": "21.5%", "choice_question": "A 20m long aluminum rod with a diameter of 14.0mm is drawn through a die with an aperture of 12.7mm. The engineering linear strain experienced by this aluminum rod is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "21.5%", "B": "17.6%", "C": "28.3%", "D": "13.4%" }, "correct_answer": "A", "explanation": "The correct answer is A (21.5%) calculated using the engineering strain formula (Δd/d₀). Option B (17.6%) is a common error from using area reduction instead of diameter change. Option C (28.3%) results from incorrectly calculating true strain. Option D (13.4%) comes from miscalculating the diameter difference as 1.3mm instead of 1.3mm.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4257, "question": "For a bronze alloy, the stress at which plastic deformation begins is 275 MPa (40,000 psi), and the modulus of elasticity is 115 GPa (16.7 x 10^6 psi). If the original specimen length is 115mm (4.5 in.), what is the maximum length to which it may be stretched without causing plastic deformation?", "answer": "the maximum length to which the specimen may be stretched without causing plastic deformation is 115.28mm (4.51 in).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（如弹性模量和应力-应变关系）来确定最大拉伸长度，答案是一个具体的数值结果。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即利用弹性模量和应力计算最大弹性变形长度，属于直接套用公式的范畴，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解塑性变形开始时的应力和弹性模量的概念，但解题步骤相对直接，只需应用胡克定律（Hooke's Law）进行简单的应变计算，然后转换为长度变化。不需要复杂的分析或多步骤计算，因此属于等级2难度。", "convertible": true, "correct_option": "115.28mm (4.51 in)", "choice_question": "For a bronze alloy, the stress at which plastic deformation begins is 275 MPa (40,000 psi), and the modulus of elasticity is 115 GPa (16.7 x 10^6 psi). If the original specimen length is 115mm (4.5 in.), what is the maximum length to which it may be stretched without causing plastic deformation?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "115.28 mm (4.51 in)", "B": "115.55 mm (4.55 in)", "C": "115.00 mm (4.53 in)", "D": "115.75 mm (4.56 in)" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using Hooke's Law (σ = Eε) where ε = ΔL/L0. The maximum elastic strain ε = σ/E = 275 MPa / 115 GPa = 0.00239. Then ΔL = ε × L0 = 0.00239 × 115 mm = 0.275 mm, giving final length 115.28 mm. Option B incorrectly uses shear modulus instead of Young's modulus. Option C is a trap for those who confuse yield point with elastic limit. Option D introduces a common error by using the ultimate tensile strength instead of yield strength.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3965, "question": "The flexural strength and associated volume fraction porosity for two specimens of the same ceramic material are as follows: \begin{tabular}{cc} \\hline \\sigma_{\\mathrm{fs}} (MPa) & \\mathbf{P} \\ \\hline 100 & 0.05 \\ 50 & 0.20 \\ \\hline \\end{tabular} (a) Compute the flexural strength for a completely nonporous specimen of this material.", "answer": "the flexural strength for a completely nonporous specimen of this material is 126 mpa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的数据（弯曲强度和孔隙率）进行计算，以得出无孔隙材料的弯曲强度。答案是一个具体的数值（126 MPa），需要通过公式和数值计算得出。 | 知识层次: 题目需要应用公式进行多步计算，并理解孔隙率与弯曲强度之间的关系，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解孔隙率与弯曲强度的关系，建立数学模型（如指数衰减关系），并进行多步计算推导。虽然选择题提供了正确选项，但解题过程涉及综合分析材料性能参数和数学运算，比单纯的概念选择题更复杂。", "convertible": true, "correct_option": "126 MPa", "choice_question": "The flexural strength and associated volume fraction porosity for two specimens of the same ceramic material are as follows: \n\\begin{tabular}{cc} \\hline \\sigma_{\\mathrm{fs}} (MPa) & \\mathbf{P} \\\\ \\hline 100 & 0.05 \\\\ 50 & 0.20 \\\\ \\hline \\end{tabular} \nCompute the flexural strength for a completely nonporous specimen of this material.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "126 MPa", "B": "112 MPa", "C": "138 MPa", "D": "89 MPa" }, "correct_answer": "A", "explanation": "The correct answer is A (126 MPa) calculated using the exponential porosity dependence equation σ = σ0 * exp(-nP). Solving the system: 100 = σ0 * exp(-0.05n) and 50 = σ0 * exp(-0.20n) yields σ0 = 126 MPa. Option B (112 MPa) is a common error from using linear extrapolation. Option C (138 MPa) results from incorrectly assuming a logarithmic relationship. Option D (89 MPa) exploits the cognitive bias of choosing mid-range values without proper calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2229, "question": "Determine whether the following statement is correct. (4) For any metal that undergoes cold deformation followed by recrystallization annealing, the grain size can be refined.", "answer": "Incorrect. If the metal is deformed at the critical deformation degree, the grain size will coarsen after recrystallization annealing.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断一个陈述的正确性（\"Determine whether the following statement is correct\"），答案直接给出了该陈述是错误的（\"Incorrect\"）并解释了原因。这符合判断题的特征，即判断给定陈述的对错。 | 知识层次: 题目不仅需要理解冷变形和再结晶退火的基本概念，还需要分析临界变形度对晶粒尺寸的影响，涉及多步概念关联和综合分析。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求考生理解冷变形和再结晶退火的基本概念，还需要掌握临界变形程度对晶粒尺寸的影响这一特定知识点。解题时需要综合分析变形程度与再结晶后晶粒尺寸的关系，并判断题目陈述的正确性。这种综合分析结果判断的能力要求高于简单的概念记忆或单一知识点应用，因此属于等级4难度。", "convertible": true, "correct_option": "Incorrect. If the metal is deformed at the critical deformation degree, the grain size will coarsen after recrystallization annealing.", "choice_question": "Determine whether the following statement is correct. (4) For any metal that undergoes cold deformation followed by recrystallization annealing, the grain size can be refined.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "For any metal that undergoes cold deformation followed by recrystallization annealing, the grain size can be refined.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is incorrect because there exists a critical deformation degree where grain size will actually coarsen after recrystallization annealing, rather than being refined. The absolute term 'any' makes this statement false, as the relationship between deformation and grain refinement is not universal but depends on specific conditions including deformation degree, temperature, and material properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3289, "question": "What is the significance of the CCT diagram of eutectoid carbon steel in practical heat treatment?", "answer": "The CCT curve can determine the heat treatment process parameters of steel during continuous cooling, such as the critical quenching cooling rate, quenching medium, and microstructure after heat treatment.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释CCT图在实际热处理中的意义，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释CCT图在实际热处理中的意义，涉及对CCT图的理解和应用，需要将理论知识与实际热处理工艺参数（如临界淬火冷却速率、淬火介质和热处理后的显微组织）联系起来，属于中等应用层次。这不仅仅是对基础概念的简单记忆，而是需要一定的分析和综合能力来理解和应用CCT图的信息。 | 难度: 在选择题中属于中等难度，需要理解CCT图的基本概念及其在热处理中的实际应用，并能将多个概念（如临界淬火冷却速率、淬火介质和热处理后的显微组织）进行关联分析。虽然题目涉及多步计算和综合分析，但在选择题型中，正确选项已经提供了明确的关联性分析，因此难度属于等级3。", "convertible": true, "correct_option": "The CCT curve can determine the heat treatment process parameters of steel during continuous cooling, such as the critical quenching cooling rate, quenching medium, and microstructure after heat treatment.", "choice_question": "What is the significance of the CCT diagram of eutectoid carbon steel in practical heat treatment?", "conversion_reason": "The answer is a standard and specific explanation, making it suitable for conversion into a multiple-choice question where this statement can serve as the correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The CCT curve determines the critical quenching cooling rate and final microstructure during continuous cooling", "B": "The CCT diagram directly shows the equilibrium phase fractions at different temperatures", "C": "The CCT curve is used to calculate the elastic modulus of the steel after heat treatment", "D": "The CCT diagram primarily indicates the corrosion resistance of the steel under various cooling rates" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the practical significance of CCT diagrams in determining cooling rates and resulting microstructures. Option B is a cognitive bias trap, confusing CCT with equilibrium phase diagrams. Option C exploits material property confusion by suggesting modulus calculation. Option D creates a professional intuition trap by associating cooling rates with corrosion resistance, which is incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3446, "question": "Since high-speed steel already has good red hardness, why is high-speed steel generally not used for die-casting molds, and why was the steel grade 3Cr2W8V developed?", "answer": "Although high-speed steel has high hardness, high wear resistance, and red hardness, its toughness and thermal fatigue properties are inferior to those of 3Cr2W8V, so high-speed steel is not used for die-casting molds.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么高速钢不用于压铸模具以及3Cr2W8V钢种的开发原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目不仅需要理解高速钢和3Cr2W8V钢的基本性能特点，还需要分析它们在特定应用场景（压铸模具）下的适用性差异，涉及材料性能的综合比较和实际应用中的权衡考量。这要求考生具备较高的综合分析能力和对材料性能与使用条件之间关系的深入理解。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解高速钢和3Cr2W8V钢的基本性能特点，还需要综合分析它们在韧性、热疲劳性能等方面的差异，并推理出材料选择背后的机理。这种题目需要考生具备深入的材料科学知识，能够对不同材料的性能进行对比分析，并理解材料选择背后的工程考量。在选择题型中，这种需要多维度综合分析和机理解释的题目属于最复杂的一类。", "convertible": true, "correct_option": "Although high-speed steel has high hardness, high wear resistance, and red hardness, its toughness and thermal fatigue properties are inferior to those of 3Cr2W8V, so high-speed steel is not used for die-casting molds.", "choice_question": "Why is high-speed steel generally not used for die-casting molds, and why was the steel grade 3Cr2W8V developed?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High-speed steel lacks sufficient thermal conductivity for efficient heat dissipation in die-casting applications", "B": "The tungsten content in high-speed steel causes excessive carbide precipitation at die-casting temperatures", "C": "High-speed steel's superior hardness leads to unacceptable tool brittleness under cyclic thermal loading", "D": "3Cr2W8V was specifically developed to optimize the cost-performance ratio for aluminum die-casting" }, "correct_answer": "C", "explanation": "The correct answer is C because while high-speed steel has excellent hardness and wear resistance, these properties actually make it too brittle for the thermal cycling stresses in die-casting. Option A is misleading because thermal conductivity is not the primary limiting factor. Option B exploits confusion about carbide precipitation kinetics. Option D is a half-truth that distracts from the fundamental material property requirements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4828, "question": "For the following pair of polymers, do the following: (1) state whether it is possible to determine whether one polymer has a higher melting temperature than the other; (2) if it is possible, note which has the higher melting temperature and then cite reason(s) for your choice; and (3) if it is not possible to decide, then state why. Linear and syndiotactic polypropylene having a weight-average molecular weight of 500,000 g/mol; linear and atactic polypropylene having a weight-average molecular weight of 750,000 g/mol", "answer": "No, it is not possible to determine which of the two polymers has the higher melting temperature. The syndiotactic polypropylene will have a higher degree of crystallinity than the atactic material. On the basis of this effect alone, the syndiotactic PP should have the greater Tm, since melting temperature increases with degree of crystallinity. However, the molecular weight for the syndiotactic polypropylene (500,000 g/mol) is less than for the atactic material (750,000 g/mol); a lowering of molecular weight generally results in a reduction of melting temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对两种聚合物的熔点进行比较，并解释原因或说明无法比较的理由。答案需要详细的文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求对两种聚合物的熔点进行比较，需要考虑多个因素（立体规整性、分子量）的综合影响，并进行权衡分析。这涉及到对聚合物结构与性能关系的深入理解，以及在不同影响因素之间进行推理判断的能力。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "No, it is not possible to determine which of the two polymers has the higher melting temperature.", "choice_question": "For the following pair of polymers, is it possible to determine whether one polymer has a higher melting temperature than the other? Linear and syndiotactic polypropylene having a weight-average molecular weight of 500,000 g/mol; linear and atactic polypropylene having a weight-average molecular weight of 750,000 g/mol", "conversion_reason": "The answer is a clear statement that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking whether it is possible to determine which polymer has a higher melting temperature.", "perplexity": { "has_perplexity": false, "perplexity_type": "None", "perplexity_level": "None", "perplexity_reason": "The question provides all necessary information for a materials science graduate student to analyze the melting temperatures of the two polymers. The molecular weights and tacticity are given, which are the key factors in determining the melting temperature. The question is designed to test the student's ability to weigh these factors against each other.", "missing_info": "None" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because the higher molecular weight of atactic PP compensates for its lower tacticity", "B": "Yes, syndiotactic PP always has higher Tm due to its regular chain packing", "C": "Yes, atactic PP has higher Tm because its higher molecular weight dominates", "D": "No, because tacticity and molecular weight effects cannot be separated in this comparison" }, "correct_answer": "D", "explanation": "The correct answer is D because tacticity (syndiotactic vs atactic) and molecular weight (500k vs 750k) both significantly affect melting temperature, and their competing effects cannot be quantitatively compared without experimental data. Option A is incorrect because molecular weight and tacticity don't 'compensate' in a predictable way. Option B is wrong because while syndiotactic PP generally has higher Tm, the much higher molecular weight of the atactic sample could potentially offset this. Option C is incorrect because tacticity effects often outweigh molecular weight effects in determining Tm.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2693, "question": "Given that the number-average relative molecular weight of linear polytetrafluoroethylene is 5×10^5, the C-C bond length is 0.154 nm, and the bond angle θ is 109°, calculate its total chain length L.", "answer": "For a linear polymer, the total chain length L depends on the bond length d between atoms, the number of bonds N, and the angle θ between adjacent bonds, i.e., L=Ndsin(θ/2). For polytetrafluoroethylene, each chain unit has 2 C atoms and 4 F atoms. First, calculate its degree of polymerization πn=M/m=5×10^5/(2×12.01+4×19.00)=5×10^3. Each chain unit has 2 C atoms, so each chain unit has two C-C main bonds. Therefore, the total number of bonds in this polymer is N=2πn=2×5×10^3=1.0×10^4. If each C-C bond length d=0.154 nm and bond angle θ=109°, then L=Ndsin(θ/2)=1.0×10^4×0.154×sin(109°/2)=1253.738 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解聚合物的总链长，答案中包含了具体的计算步骤和最终数值结果。 | 知识层次: 题目需要进行多步计算，包括计算聚合度、键的数量，并应用公式计算链的总长度。虽然涉及的概念和公式相对明确，但需要综合运用多个知识点并进行数值计算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如聚合度、键长、键角等）并进行多步计算（包括聚合度计算、键数计算和最终链长计算）。虽然题目提供了公式和具体数值，但解题过程涉及多个步骤和概念的综合应用，对学生的计算能力和概念理解有一定要求。", "convertible": true, "correct_option": "1253.738 nm", "choice_question": "Given that the number-average relative molecular weight of linear polytetrafluoroethylene is 5×10^5, the C-C bond length is 0.154 nm, and the bond angle θ is 109°, calculate its total chain length L.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1253.738 nm", "B": "627.869 nm", "C": "2507.476 nm", "D": "835.825 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (1253.738 nm) because it accurately calculates the total chain length considering the number-average relative molecular weight, C-C bond length, and bond angle. Option B (627.869 nm) is half the correct value, exploiting the common mistake of not properly accounting for the tetrahedral bond angle. Option C (2507.476 nm) doubles the correct value, targeting those who might incorrectly consider the molecular weight per monomer unit. Option D (835.825 nm) is 2/3 of the correct value, designed to trap those who might misapply the bond angle calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 660, "question": "List the various possible mechanisms of work hardening", "answer": "The mechanisms of work hardening are mainly the interactions between dislocations, such as the formation of jogs, dislocation intersection and entanglement, the interaction between moving dislocations and forest dislocations, the formation of Lomer-Cottrell locks, and the formation of solute atom atmospheres due to the interaction between solute atoms and dislocations.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求列出各种可能的加工硬化机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求列举并解释加工硬化的多种机制，涉及位错之间的复杂相互作用（如jog形成、位错交叉和纠缠、移动位错与森林位错的相互作用、Lomer-Cottrell锁的形成、溶质原子与位错的相互作用等）。这需要深入理解位错理论并能综合分析多种机制，属于对材料变形机理的复杂分析。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生全面掌握并分析多种位错相互作用机制，包括位错交截、缠结、林位错相互作用、Lomer-Cottrell锁形成以及溶质原子气团形成等复杂现象。这些知识点不仅需要深入理解材料变形机理，还需要综合运用多个概念进行推理分析。在选择题型中，能够准确识别和区分所有这些机制需要极高的知识掌握深度和分析能力，远超一般选择题的认知要求。", "convertible": true, "correct_option": "The mechanisms of work hardening are mainly the interactions between dislocations, such as the formation of jogs, dislocation intersection and entanglement, the interaction between moving dislocations and forest dislocations, the formation of Lomer-Cottrell locks, and the formation of solute atom atmospheres due to the interaction between solute atoms and dislocations.", "choice_question": "Which of the following correctly describes the mechanisms of work hardening?", "conversion_reason": "The answer is a standard description of the mechanisms of work hardening, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The increase in dislocation density and their mutual interactions, including formation of Lomer-Cottrell locks and solute atmospheres", "B": "The reduction in grain size due to plastic deformation, leading to Hall-Petch strengthening", "C": "The formation of new phase precipitates during deformation, similar to age hardening", "D": "The alignment of dislocations along slip planes, reducing their mobility through geometric softening" }, "correct_answer": "A", "explanation": "Option A correctly describes the primary mechanisms of work hardening involving dislocation interactions. Option B is incorrect because grain refinement is not a direct mechanism of work hardening (though it may occur concurrently). Option C is a trap using precipitation hardening concepts. Option D uses reverse logic by suggesting dislocation alignment reduces mobility, when in reality it's their entanglement that causes hardening.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2193, "question": "This shows, what effect does recovery have on recrystallization?", "answer": "After polygonization, the dislocation energy decreases, reducing the stored energy and thereby diminishing the driving force for subsequent recrystallization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释恢复对再结晶的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及恢复过程对再结晶的影响机制，需要理解位错能量变化、储存能量减少以及再结晶驱动力减小的因果关系。这需要对材料科学中的位错理论、恢复和再结晶过程有深入的理解，并进行推理分析，属于复杂分析的层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解回复（recovery）和再结晶（recrystallization）的基本概念，还需要深入掌握位错多边形化（polygonization）过程中位错能降低的机理，以及这对后续再结晶驱动力（driving force）的影响。这涉及到多个材料科学核心概念的串联和机理层面的解释，需要考生具备复杂现象全面分析的能力。在选择题型中，这种需要综合运用多个高阶概念并进行机理推理的题目属于最难的一类。", "convertible": true, "correct_option": "After polygonization, the dislocation energy decreases, reducing the stored energy and thereby diminishing the driving force for subsequent recrystallization.", "choice_question": "What effect does recovery have on recrystallization?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recovery increases the dislocation density, providing more nucleation sites for recrystallization", "B": "After polygonization, the dislocation energy decreases, reducing the stored energy and thereby diminishing the driving force for subsequent recrystallization", "C": "Recovery creates high-angle grain boundaries that accelerate recrystallization kinetics", "D": "The thermal activation during recovery process directly initiates recrystallization" }, "correct_answer": "B", "explanation": "The correct answer is B because recovery through polygonization reduces dislocation energy and stored energy, decreasing the driving force for recrystallization. Option A is incorrect because recovery actually reduces dislocation density through annihilation and rearrangement. Option C is a trap as it confuses recovery with deformation - only deformation creates high-angle boundaries. Option D exploits the common misconception that thermal processes are directly cumulative.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 707, "question": "What are the characteristics of pore changes during secondary recrystallization", "answer": "During secondary recrystallization, pores are encapsulated within the grains", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述二次再结晶过程中孔隙变化的特征，答案提供了文字解释而非选择、判断或计算。 | 知识层次: 题目涉及对二次再结晶过程中孔隙变化的特征描述，需要理解再结晶的基本原理，并能够将孔隙行为与晶粒生长过程关联起来进行分析。这属于中等应用层次，需要多步概念关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解二次再结晶过程中孔隙变化的基本概念，并能够将孔隙被晶粒包裹这一特征与二次再结晶过程关联起来。虽然不需要多步计算，但需要对材料科学中的再结晶过程有较好的理解，属于中等应用层次的知识点。", "convertible": true, "correct_option": "During secondary recrystallization, pores are encapsulated within the grains", "choice_question": "What are the characteristics of pore changes during secondary recrystallization?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pores are encapsulated within the grains", "B": "Pores migrate to grain boundaries and coalesce", "C": "Pores undergo Ostwald ripening and disappear", "D": "Pores transform into dislocation loops" }, "correct_answer": "A", "explanation": "During secondary recrystallization, abnormal grain growth leads to pores being trapped inside the growing grains (A). Option B is incorrect because it describes primary recrystallization behavior. Option C is a common misconception as Ostwald ripening occurs in liquid-phase sintering. Option D is a quantum mechanics concept misapplied to materials science.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3990, "question": "The bonding forces between adhesive and adherend surfaces are thought to be(a) Electrostatic(b) Covalent(c) Chemical", "answer": "The bonding forces between adhesive and adherend surfaces are thought to be electrostatic.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的选项(a)、(b)、(c)中选择一个正确答案，符合选择题的特征。 | 知识层次: 题目考查对粘合剂与被粘物表面之间作用力类型的基本概念记忆，属于基础概念的选择题，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生对粘合剂与被粘物表面之间的结合力类型有一定的理解和辨析能力。正确选项（静电作用）需要考生从三个选项中识别出最符合理论描述的答案，而不仅仅是简单的概念识别。这要求考生对不同类型的结合力有基本的区分能力，但不需要进行复杂的分析或深度理解。", "convertible": true, "correct_option": "Electrostatic", "choice_question": "The bonding forces between adhesive and adherend surfaces are thought to be", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Electrostatic", "B": "Covalent", "C": "Van der Waals", "D": "Mechanical interlocking" }, "correct_answer": "A", "explanation": "The correct answer is A (Electrostatic) because adhesive bonding primarily involves electrostatic forces between molecules at the interface. B (Covalent) is a strong trap as it appeals to the intuition of 'strong chemical bonds' but covalent bonds rarely form between adhesives and adherends. C (Van der Waals) is partially correct but too weak to account for most adhesive bonding strength. D (Mechanical interlocking) exploits the common misconception that surface roughness is the main bonding mechanism, while in reality it only contributes secondarily.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3365, "question": "What is alloy cementite, and how does its performance compare with cementite", "answer": "Alloy cementite is formed when alloying elements dissolve into cementite. Alloy cementite has higher stability than ordinary cementite and exhibits a more significant strengthening effect on the steel matrix.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释什么是合金渗碳体，并比较其性能与普通渗碳体的差异，需要文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对合金渗碳体的基本定义和性能比较的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目要求考生不仅知道合金渗碳体的定义，还需要理解其与普通渗碳体的性能比较。这涉及到基础概念的记忆和简单比较分析，属于概念解释和描述的层次，但不需要复杂的推理或多概念整合。", "convertible": true, "correct_option": "Alloy cementite is formed when alloying elements dissolve into cementite. Alloy cementite has higher stability than ordinary cementite and exhibits a more significant strengthening effect on the steel matrix.", "choice_question": "Which of the following statements correctly describes alloy cementite and its performance compared with cementite?", "conversion_reason": "The answer is a standard description of alloy cementite and its properties, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Alloy cementite is formed when alloying elements dissolve into cementite. Alloy cementite has higher stability than ordinary cementite and exhibits a more significant strengthening effect on the steel matrix.", "B": "Alloy cementite is a separate phase that forms alongside cementite. It has lower hardness but better toughness compared to pure cementite due to reduced carbon content.", "C": "Alloy cementite refers to cementite with nanostructured grain boundaries. Its enhanced performance comes primarily from grain boundary strengthening rather than alloying effects.", "D": "Alloy cementite is formed when cementite decomposes under alloying elements. It shows reduced stability but improved ductility in the steel matrix." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the formation of alloy cementite through dissolution of alloying elements and its enhanced properties. Option B incorrectly describes it as a separate phase with reduced carbon content. Option C confuses alloy cementite with nanostructured materials. Option D falsely suggests decomposition of cementite and reversed stability-ductility relationship. These distractors exploit common misconceptions about phase formation, strengthening mechanisms, and stability-ductility tradeoffs in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3099, "question": "What are the performance characteristics of silicon carbide fibers?", "answer": "High melting point, high strength, high modulus ceramic fibers, mainly used to reinforce metals and ceramics. The outstanding feature is excellent high-temperature strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释硅碳纤维的性能特点，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查对碳化硅纤维性能特征的基础概念记忆和理解，属于定义和分类层面的知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及硅碳纤维的性能特点，但正确选项提供了明确的性能描述和主要用途，属于概念解释和描述的层次。考生需要理解并记忆硅碳纤维的基本特性，但不需要进行复杂的分析或比较。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "High melting point, high strength, high modulus ceramic fibers, mainly used to reinforce metals and ceramics. The outstanding feature is excellent high-temperature strength.", "choice_question": "Which of the following best describes the performance characteristics of silicon carbide fibers?", "conversion_reason": "The answer is a standard description of the performance characteristics of silicon carbide fibers, which can be used as the correct option in a multiple-choice question. The original question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High melting point, high strength, high modulus ceramic fibers with excellent high-temperature strength", "B": "Low density polymer fibers with moderate strength but exceptional fracture toughness at cryogenic temperatures", "C": "Metallic fibers exhibiting superb ductility and electrical conductivity but limited oxidation resistance", "D": "Semiconductor fibers with tunable bandgap properties primarily used in optoelectronic applications" }, "correct_answer": "A", "explanation": "Option A correctly describes silicon carbide fibers as high-performance ceramic fibers with exceptional high-temperature capabilities. Option B incorrectly describes polymer fiber properties, exploiting confusion between ceramic and polymer fiber characteristics. Option C describes metallic fibers, creating a category confusion trap. Option D describes semiconductor properties, exploiting the fact that silicon carbide can have semiconductor properties in bulk form but not in fiber form for structural applications.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4144, "question": "Which of the following characteristics are displayed by soft magnetic materials in terms of hysteresis loop size?", "answer": "Soft materials have relatively small relative hysteresis loops.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择关于软磁材料磁滞回线特性的正确答案 | 知识层次: 题目考查软磁材料的基本特性——磁滞回线大小的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求识别软磁材料的基本特性（磁滞回线较小），属于直接记忆的基础概念，无需复杂分析或比较。", "convertible": true, "correct_option": "Soft materials have relatively small relative hysteresis loops.", "choice_question": "Which of the following characteristics are displayed by soft magnetic materials in terms of hysteresis loop size?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provided is a clear and distinct option that can serve as the correct choice in a single-answer multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Exhibit narrow hysteresis loops with low coercivity", "B": "Show wide hysteresis loops proportional to their high permeability", "C": "Display hysteresis loops identical to hard magnetic materials but with lower saturation magnetization", "D": "Have no measurable hysteresis due to perfect domain alignment" }, "correct_answer": "A", "explanation": "Correct answer A is right because soft magnetic materials are characterized by narrow hysteresis loops indicating easy domain wall movement and low energy loss. Option B is a permeability misconception trap - while soft materials have high permeability, this actually correlates with narrower loops, not wider. Option C exploits the common AI confusion between loop shape and magnetization magnitude. Option D is an idealization trap suggesting perfect behavior that doesn't exist in real materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4308, "question": "Give the approximate temperature at which creep deformation becomes an important consideration for lead.", "answer": "for pb: -33 degrees c (-27 degrees f)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从多个选项中选择或判断对错，也不需要复杂的计算过程。答案是一个具体的数值，属于简答题类型。 | 知识层次: 题目考查对铅材料蠕变温度这一特定数值的记忆，属于基础概念的记忆性知识，不需要复杂的应用或分析过程。 | 难度: 在选择题型中，该题目仅要求记忆铅的蠕变温度这一具体数值，属于基础概念记忆范畴。题目不涉及概念解释或复杂分析，只需直接回忆知识点即可作答，因此属于最低难度等级。", "convertible": true, "correct_option": "-33 degrees C (-27 degrees F)", "choice_question": "At approximately what temperature does creep deformation become an important consideration for lead?", "conversion_reason": "The answer is a specific temperature value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-33°C (-27°F)", "B": "150°C (302°F)", "C": "0.3 x melting temperature (97.5°C/207.5°F)", "D": "Room temperature (20°C/68°F)" }, "correct_answer": "A", "explanation": "The correct answer is A because lead has an exceptionally low homologous temperature for creep onset due to its low melting point (327.5°C). Option B exploits the common misconception that creep only occurs at high temperatures. Option C uses the standard '0.3-0.5 x melting temperature' rule but fails for lead's unique case. Option D plays on the intuitive but incorrect assumption that creep requires elevated temperatures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4057, "question": "Select T/F for the following statement regarding aluminum / aluminum alloys: Aluminum alloys are generally superior to pure aluminum, in terms of yield strength, because their microstructures often contain precipitate phases that strain the lattice, thereby hardening the alloy relative to pure aluminum.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断陈述的对错（Select T/F），答案形式为简单的T/F判断，符合判断题的特征。 | 知识层次: 题目考查对铝合金强化机制的基本概念记忆和理解，即通过析出相引起晶格应变从而强化合金的原理。这属于材料科学中关于金属强化机制的基础知识，不需要复杂的分析或综合应用。 | 难度: 在选择题中属于中等偏下难度，需要理解铝合金和纯铝的基本区别以及沉淀相的作用，但不需要复杂的分析或比较多个概念", "convertible": true, "correct_option": "T", "choice_question": "Select T/F for the following statement regarding aluminum / aluminum alloys: Aluminum alloys are generally superior to pure aluminum, in terms of yield strength, because their microstructures often contain precipitate phases that strain the lattice, thereby hardening the alloy relative to pure aluminum.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All precipitation-hardened aluminum alloys exhibit higher electrical conductivity than pure aluminum due to the reduced electron scattering in their strained lattice structures.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because while precipitation hardening increases strength by straining the lattice, this strain actually increases electron scattering and reduces conductivity compared to pure aluminum. The statement reverses the actual conductivity relationship and makes an absolute claim ('all') that is incorrect. Many students might incorrectly associate increased strength with improved conductivity, or overlook the absolute nature of the claim.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4503, "question": "For some viscoelastic polymers that are subjected to stress relaxation tests, the stress decays with time according to\n\\[\n\\sigma(t)=\\sigma(0) \\exp \\left(-\\frac{t}{\\tau}\\right)\n\\]\nwhere \\sigma(t) and \\sigma(t) represent the time-dependent and initial (i.e., time =0 ) stresses, respectively, and t and \\tau denote elapsed time and the relaxation time; \\tau is a time-independent constant characteristic of the material. A specimen of some viscoelastic polymer the stress relaxation of which obeys Equation 15.10 was suddenly pulled in tension to a measured strain of 0.6 ; the stress necessary to maintain this constant strain was measured as a function of time. Determine E_{\\tau}(10) for this material if the initial stress level was 2.76 MPa(400 psi), which dropped to 1.72 MPa (250 psi) after 60s.", "answer": "e_{\\tau}(10) = 4.25 \\text{ mpa (616 psi)}", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和初始条件进行数值计算，最终得出一个具体的数值结果（E_{\\tau}(10) = 4.25 \\text{ mpa (616 psi)}），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括应用给定的应力松弛公式和计算弹性模量，需要理解应力松弛的基本概念和公式应用，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等难度，需要理解应力松弛的概念，应用指数衰减公式进行多步计算，并综合分析初始条件和时间变化对结果的影响。虽然题目提供了具体数值和公式，但解题过程涉及多个步骤和概念关联，对学生的应用能力有一定要求。", "convertible": true, "correct_option": "4.25 MPa (616 psi)", "choice_question": "For some viscoelastic polymers that are subjected to stress relaxation tests, the stress decays with time according to the equation σ(t) = σ(0) exp(-t/τ). A specimen of this polymer was pulled in tension to a strain of 0.6, with an initial stress level of 2.76 MPa (400 psi) that dropped to 1.72 MPa (250 psi) after 60s. Determine E_τ(10) for this material:", "conversion_reason": "The question involves a calculation with a specific numerical answer, making it suitable for conversion to a multiple-choice format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.25 MPa (616 psi)", "B": "3.82 MPa (554 psi)", "C": "2.87 MPa (416 psi)", "D": "5.12 MPa (742 psi)" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算松弛时间τ=96.6s后，代入E_τ(t)=σ(t)/ε公式得到的。干扰项B设计为忽略对数计算步骤直接线性外推的常见错误；干扰项C利用初始应力与最终应力的简单平均值产生直觉陷阱；干扰项D则通过倒置时间参数制造计算方向性错误。所有干扰项都利用了材料科学中应力松弛分析时容易产生的典型认知偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1633, "question": "The dislocation that can produce cross-slip must be a _ (20) dislocation", "answer": "screw-type", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（screw-type）作为答案，而不是从多个选项中选择或判断对错，也不需要复杂的计算过程。这种形式符合简答题的特征。 | 知识层次: 题目考查位错类型的基本概念记忆，特别是关于螺型位错（screw-type dislocation）能够产生交叉滑移的特性。这属于对材料科学基础知识的直接回忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需考生回忆位错类型的基本定义和特性（如螺型位错可以发生交滑移）。题目不涉及复杂概念体系或分析过程，属于最基础的定义简答级别。", "convertible": true, "correct_option": "screw-type", "choice_question": "The dislocation that can produce cross-slip must be a:", "conversion_reason": "The answer is a standard term (screw-type), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "screw-type", "B": "edge-type", "C": "mixed-type", "D": "partial" }, "correct_answer": "A", "explanation": "The correct answer is screw-type because cross-slip requires dislocations to change slip planes, which is only possible for screw dislocations due to their non-planar core structure. Edge dislocations (B) are confined to their original slip plane. Mixed-type dislocations (C) can only cross-slip if their screw component dominates. Partial dislocations (D) are inherently limited by their stacking fault ribbon, making cross-slip energetically unfavorable. The distractors exploit common misconceptions: (B) triggers the 'visible slip steps' heuristic, (C) appeals to compromise reasoning, and (D) exploits confusion between perfect/partial dislocation mobility.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1766, "question": "7. The reason why glass is isotropic is (15)", "answer": "The long-range disorder of the glass structure exhibits statistical homogeneity macroscopically", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求用文字解释玻璃各向同性的原因，答案是一个简短的论述性回答，符合简答题的特征 | 知识层次: 题目考查玻璃各向同性的基本原因，属于对材料结构特性的基础概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 该题目属于基础概念记忆层次，要求考生理解玻璃各向同性的原因。虽然需要掌握\"长程无序\"和\"统计均匀性\"等专业术语，但属于单一概念的解释性题目，不需要进行多概念比较或复杂推理。在选择题型中属于中等难度，高于简单定义识记但低于需要综合分析的多概念题目。", "convertible": true, "correct_option": "The long-range disorder of the glass structure exhibits statistical homogeneity macroscopically", "choice_question": "The reason why glass is isotropic is:", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The long-range disorder of the glass structure exhibits statistical homogeneity macroscopically", "B": "The rapid quenching process aligns all molecular dipoles in random orientations", "C": "The covalent network structure prevents preferential crystallographic directions", "D": "The absence of grain boundaries eliminates anisotropic effects" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental reason for glass isotropy - the statistical homogeneity of disordered structure at macroscopic scale. Distractor B exploits the common misconception about dipole alignment during quenching. Distractor C uses a partially correct statement about covalent networks but incorrectly attributes isotropy to this feature. Distractor D leverages the grain boundary concept from polycrystalline materials, creating a plausible but irrelevant explanation for amorphous materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2601, "question": "Which four quantum numbers can determine the spatial position and energy of an electron in an atom?", "answer": "Principal quantum number n, orbital angular momentum quantum number li, magnetic quantum number mi, and spin angular momentum quantum number si", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举四个量子数，答案是以文字形式给出的解释和论述，没有提供选项或需要计算。 | 知识层次: 题目考查对量子数这一基础概念的记忆和理解，不需要复杂的应用或分析，仅需回答四个量子数的名称即可。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要学生准确掌握四个量子数的名称及其作用（确定电子空间位置和能量）。这比单纯记忆单个定义（等级1）要求更高，但不需要进行复杂的概念体系阐述或比较分析（等级3）。学生只需正确识别四个量子数的组合即可作答。", "convertible": true, "correct_option": "Principal quantum number n, orbital angular momentum quantum number li, magnetic quantum number mi, and spin angular momentum quantum number si", "choice_question": "Which of the following sets of quantum numbers can determine the spatial position and energy of an electron in an atom?", "conversion_reason": "The answer is a standard set of terms (quantum numbers) that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Principal quantum number n, orbital angular momentum quantum number li, magnetic quantum number mi, and spin angular momentum quantum number si", "B": "Principal quantum number n, orbital angular momentum quantum number li, and magnetic quantum number mi", "C": "Principal quantum number n, orbital angular momentum quantum number li, and spin angular momentum quantum number si", "D": "Principal quantum number n, magnetic quantum number mi, and spin angular momentum quantum number si" }, "correct_answer": "A", "explanation": "The correct answer is A because all four quantum numbers (n, li, mi, si) are required to fully determine the spatial position and energy of an electron in an atom. Option B is missing the spin quantum number, which is crucial for distinguishing between electrons in the same orbital. Option C lacks the magnetic quantum number, which specifies the orbital's orientation in space. Option D omits the orbital angular momentum quantum number, which determines the shape of the orbital. These distractors exploit the common misconception that spin can be ignored (B), or that spatial orientation (C) or orbital shape (D) are less critical than they actually are.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 391, "question": "Both thermoplastic and thermosetting plastics can be reused.", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（Both thermoplastic and thermosetting plastics can be reused），并要求判断其正确性（答案给出×表示错误），这符合判断题的特征。 | 知识层次: 题目考查对热塑性塑料和热固性塑料基本特性的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念正误判断题，仅需记忆热塑性塑料和热固性塑料的基本特性即可作答。在选择题型中，这类直接考察定义记忆的题目属于最简单级别，无需复杂分析或推理过程。", "convertible": true, "correct_option": "×", "choice_question": "Both thermoplastic and thermosetting plastics can be reused.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect ionic bonding characteristics.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics exhibit ionic bonding, this is not universally true. Some ceramics (like silicon carbide) show predominantly covalent bonding, and many exhibit mixed bonding characteristics. The statement's use of 'all' makes it incorrect due to the diversity in ceramic bonding types.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3183, "question": "Explain the concept of undercooling", "answer": "The temperature difference between the actual crystallization temperature and the theoretical crystallization temperature is called the undercooling (ΔT=Tm−Tn). It is required by the thermodynamic conditions of phase transformation. Only when ΔT>0 can the condition that the free energy of the solid phase is lower than that of the liquid phase be achieved. The free energy difference between the liquid and solid phases is the driving force for crystallization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释\"undercooling\"的概念，答案提供了详细的文字解释和论述，包括定义、公式和热力学条件的说明，符合简答题的特征。 | 知识层次: 题目主要考查对undercooling这一基础概念的定义和基本原理的记忆与理解，涉及温度差和自由能差等基本概念，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求解释过冷的概念，并涉及基本的温度差和热力学条件，但不需要复杂的分析或比较多个概念。正确选项提供了清晰的定义和基本原理，属于中等难度的选择题。", "convertible": true, "correct_option": "The temperature difference between the actual crystallization temperature and the theoretical crystallization temperature is called the undercooling (ΔT=Tm−Tn). It is required by the thermodynamic conditions of phase transformation. Only when ΔT>0 can the condition that the free energy of the solid phase is lower than that of the liquid phase be achieved. The free energy difference between the liquid and solid phases is the driving force for crystallization.", "choice_question": "Which of the following best describes the concept of undercooling?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The temperature difference between the actual crystallization temperature and the theoretical melting temperature, providing the driving force for phase transformation", "B": "The energy barrier that must be overcome for nucleation to occur in a supercooled liquid", "C": "The minimum temperature difference required to initiate recrystallization in deformed metals", "D": "The hysteresis effect observed during repeated melting and solidification cycles" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines undercooling as the temperature difference between actual crystallization (Tn) and theoretical melting (Tm) points. This ΔT provides the thermodynamic driving force for solidification. Option B describes the activation energy for nucleation, a related but distinct concept. Option C refers to recrystallization annealing, a completely different phenomenon. Option D describes thermal hysteresis, which is unrelated to undercooling. The distractors exploit common confusions between nucleation energy (B), recrystallization conditions (C), and thermal cycling effects (D) that are often conflated with undercooling in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4615, "question": "Visible light having a wavelength of 6 x 10^-7 m appears orange. Compute the energy of a photon of this light.", "answer": "the energy of the photon is 3.31 x 10^-19 j (2.07 ev).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算光子的能量，需要使用公式（如E=hc/λ）进行数值计算，答案也是具体的数值结果。 | 知识层次: 题目要求计算光子的能量，涉及基本公式（E=hc/λ）的直接应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（E = hc/λ）进行计算，无需额外的概念理解或步骤组合。题目提供了所有必要参数，且计算过程简单直接，属于最基础的难度等级。", "convertible": true, "correct_option": "3.31 x 10^-19 j (2.07 ev)", "choice_question": "Visible light having a wavelength of 6 x 10^-7 m appears orange. What is the energy of a photon of this light?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.31 x 10^-19 J", "B": "1.24 x 10^-19 J", "C": "4.97 x 10^-19 J", "D": "6.63 x 10^-19 J" }, "correct_answer": "A", "explanation": "正确答案A通过E=hc/λ计算得出，其中h=6.626x10^-34 J·s，c=3x10^8 m/s。干扰项B错误使用了eV单位但未转换，C错误地将波长当作频率计算，D直接使用了普朗克常数h的值而未进行完整计算。这些干扰项利用了材料科学中常见的单位混淆和公式误用陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2680, "question": "A solid solution contains x(MgO) at 30% and x(LiF) at 70%. Calculate the mass fractions of Li1+, Mg2+, F1-, and O2-. The relative atomic masses of Mg, O, Li, and F are 24.31, 16.00, 6.94, and 19.00, respectively.", "answer": "w(Li+) = (0.7 × 6.94) / [0.3 × (24.31 + 16) + 0.7 × (6.94 + 19)] = 16%\\nw(Mg2+) = (0.3 × 24.31) / [0.3 × (24.31 + 16) + 0.7 × (6.94 + 19)] = 24%\\nw(F-) = (0.7 × 19) / [0.3 × (24.31 + 16) + 0.7 × (6.94 + 19)] = 44%\\nw(O2-) = (0.3 × 16) / [0.3 × (24.31 + 16) + 0.7 × (6.94 + 19)] = 16%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算，涉及质量分数的计算和公式应用，答案也是具体的数值结果。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，需要将给定的摩尔分数转换为质量分数，并进行相应的数值计算。虽然涉及多个步骤，但每个步骤都是直接套用公式，没有复杂的综合分析或推理过程。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然涉及多个离子的质量分数计算，但每个计算步骤都是直接套用相同的质量分数公式，且各步骤之间相互独立，没有复杂的逻辑转换或组合。题目主要考察对基本质量分数公式的理解和简单应用能力，符合等级2的简单公式应用计算标准。", "convertible": true, "correct_option": "w(Li+) = 16%, w(Mg2+) = 24%, w(F-) = 44%, w(O2-) = 16%", "choice_question": "A solid solution contains x(MgO) at 30% and x(LiF) at 70%. The mass fractions of Li1+, Mg2+, F1-, and O2- are:", "conversion_reason": "The question involves a calculation with a definite answer, which can be presented as a multiple-choice question with the correct option derived from the given solution.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "w(Li+) = 16%, w(Mg2+) = 24%, w(F-) = 44%, w(O2-) = 16%", "B": "w(Li+) = 14%, w(Mg2+) = 26%, w(F-) = 42%, w(O2-) = 18%", "C": "w(Li+) = 18%, w(Mg2+) = 22%, w(F-) = 46%, w(O2-) = 14%", "D": "w(Li+) = 15%, w(Mg2+) = 25%, w(F-) = 45%, w(O2-) = 15%" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算各离子的摩尔分数和相对原子质量得出的。干扰项B利用了常见的第一印象错误，将Mg2+和O2-的质量分数简单对调。干扰项C设计为数值接近但整体偏离，利用了计算过程中可能出现的四舍五入误差陷阱。干扰项D则采用了对称分布的心理暗示，这种分布在材料科学计算中看似合理但实际上不符合本题的化学计量关系。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2718, "question": "When the temperature decreases from 600°C to 300°C, the equilibrium vacancy concentration in $\\mathtt{Ge}$ crystal decreases by 6 orders of magnitude. Calculate the vacancy formation energy in the Ge crystal.", "answer": "$$ \\\\begin{array}{r l}&{\\\\frac{C_{\\\\tau_{1}}}{C_{\\\\tau_{2}}}=\\\\frac{1}{10^{6}}=\\\\frac{A\\\\exp\\\\left(-\\\\frac{E_{\\\\mathrm{v}}}{k T_{1}}\\\\right)}{A\\\\exp\\\\left(-\\\\frac{E_{\\\\mathrm{v}}}{k T_{2}}\\\\right)}=\\\\mathrm{e}^{\\\\frac{\\\\varepsilon_{\\\\mathrm{v}}}{k}\\\\left(\\\\frac{1}{T_{2}}-\\\\frac{1}{T_{1}}\\\\right)}-\\\\ln10^{6}}\\\\ &{\\\\qquad=\\\\frac{E_{\\\\mathrm{v}}}{\\\\frac{1}{k}\\\\left(\\\\frac{1}{T_{2}}-\\\\frac{1}{T_{1}}\\\\right)}}\\\\ &{E_{\\\\mathrm{v}}=\\\\frac{-\\\\ln10^{6}}{\\\\frac{1}{873}-\\\\frac{1}{573}}=\\\\frac{-13,8\\\\times8,617\\\\times10^{-5}}{1.145\\\\times10^{-3}-1.745\\\\times10^{-3}}=1.98\\\\mathrm{(eV)}}\\\\end{array}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解空缺形成能，答案中包含了具体的计算步骤和公式推导，符合计算题的特征。 | 知识层次: 题目涉及多步计算和公式应用，需要理解平衡空位浓度与温度的关系，并能够正确应用自然对数和指数函数进行推导。虽然不涉及复杂的综合分析或机理解释，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及多步计算和概念关联，包括平衡空位浓度与温度的关系、能量计算等。虽然题目提供了正确的计算步骤，但在选择题型中，学生需要理解并验证这些步骤的正确性，这需要一定的综合分析能力。", "convertible": true, "correct_option": "1.98 eV", "choice_question": "When the temperature decreases from 600°C to 300°C, the equilibrium vacancy concentration in $\\mathtt{Ge}$ crystal decreases by 6 orders of magnitude. The vacancy formation energy in the Ge crystal is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.98 eV", "B": "0.99 eV", "C": "3.96 eV", "D": "2.85 eV" }, "correct_answer": "A", "explanation": "The correct answer is A (1.98 eV) because it is derived from the Arrhenius equation for vacancy concentration, considering the 6-order magnitude decrease between 600°C and 300°C. Option B (0.99 eV) is a cognitive bias trap, appearing plausible as half the correct value but ignoring the logarithmic relationship. Option C (3.96 eV) exploits the intuition that higher temperature changes require higher energy, but is actually double the correct value. Option D (2.85 eV) is a professional intuition trap, mimicking typical values for other semiconductor materials like Si, but incorrect for Ge specifically.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 272, "question": "What is phase transition?", "answer": "Phase transition is the mutual transformation between different phases of a material system.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"phase transition\"进行文字解释和论述，答案提供了概念的定义和说明，符合简答题的特征 | 知识层次: 题目考查基本概念的记忆和理解，即相变的定义，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察对\"相变\"这一基础概念的定义记忆，属于最基础的知识点掌握要求。正确选项直接给出了相变的定义，不需要任何解释、比较或分析过程，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Phase transition is the mutual transformation between different phases of a material system.", "choice_question": "Which of the following best defines phase transition?", "conversion_reason": "The answer is a standard definition of a scientific concept, which can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Phase transition is the mutual transformation between different phases of a material system", "B": "Phase transition occurs when a material's crystal structure changes without altering its chemical composition", "C": "Phase transition refers to the abrupt change in mechanical properties at a critical temperature", "D": "Phase transition describes the continuous evolution of material properties with changing environmental conditions" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines phase transition as the transformation between different phases (solid, liquid, gas, or different crystal structures). Option B is a cognitive bias trap - while often true, it excludes important cases like liquid-gas transitions. Option C is an intuition trap, confusing phase transitions with property changes that may accompany them. Option D is a multi-level verification trap, describing gradual changes rather than the defining characteristic of phase transitions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1219, "question": "Dislocations belong to crystal defects and also to line defects.", "answer": "~\\\\surd~", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（对错），答案使用了判断题常见的符号（√）表示正确。 | 知识层次: 题目考查对晶体缺陷分类的基本概念记忆，属于定义和分类的基础知识层次。 | 难度: 在选择题型中，该题目属于非常基础的概念正误判断。题目仅要求考生记忆并识别位错（dislocations）属于晶体缺陷和线缺陷这一基本分类知识，不需要进行任何概念理解或复杂分析。这种类型的题目只需要考生对基础定义和分类有简单的记忆即可正确回答，因此属于难度等级1。", "convertible": true, "correct_option": "~\\\\surd~", "choice_question": "Dislocations belong to crystal defects and also to line defects.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All dislocations in crystalline materials must always be edge dislocations or screw dislocations, with no intermediate types possible.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While edge and screw dislocations are the two fundamental types, real dislocations often exhibit mixed character with both edge and screw components. The statement's use of 'must always' and 'no intermediate types' is an absolute claim that doesn't account for the continuum of possible dislocation orientations in actual crystals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1622, "question": "If different atomic planes in a crystal are represented by letters such as A, B, C, D, etc., the stacking sequence of atoms in a face-centered cubic crystal is _(1)_, and the stacking sequence of atoms in a hexagonal close-packed crystal is _(2)_.", "answer": "(1) ABCABCABC...; (2) ABABAB.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的堆叠序列，需要文字描述而非选择、判断或计算。 | 知识层次: 题目考查对晶体结构中面心立方和六方密堆积原子堆垛序列的基础概念记忆，属于基本原理的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆两种晶体结构（面心立方和六方密堆积）的原子堆垛序列。题目直接给出了正确选项，无需进行复杂的分析或推理。属于基础概念记忆的简单题目，符合等级1的基本定义简答难度。", "convertible": true, "correct_option": "(1) ABCABCABC...; (2) ABABAB.", "choice_question": "If different atomic planes in a crystal are represented by letters such as A, B, C, D, etc., the stacking sequence of atoms in a face-centered cubic crystal is _(1)_, and the stacking sequence of atoms in a hexagonal close-packed crystal is _(2)_. Which of the following correctly fills in the blanks?", "conversion_reason": "The answer is a standard terminology and can be presented as a choice among other possible stacking sequences.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(1) ABCABCABC...; (2) ABABAB", "B": "(1) ABABAB...; (2) ABCABCABC", "C": "(1) ABACABAC...; (2) ABABAB", "D": "(1) ABCABCABC...; (2) ABCABCABC" }, "correct_answer": "A", "explanation": "The correct stacking sequence for FCC is ABCABCABC... due to its cubic symmetry with 3-layer periodicity, while HCP has ABABAB... with 2-layer periodicity. Option B reverses these sequences, exploiting common symmetry confusion. Option C introduces a non-existent ABAC sequence that mimics but distorts the real patterns. Option D makes HCP identical to FCC, a subtle trap since both are close-packed but with different stacking sequences.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3944, "question": "As temperature decreases, the fraction of total number of atoms that are capable of diffusive motion(a) increases.(b) decreases.", "answer": "As temperature decreases, the fraction of the total number of atoms that are capable of diffusive motion decreases.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(a)和(b)中选择正确答案 | 知识层次: 题目考查对温度与原子扩散能力关系这一基本概念的记忆和理解，属于材料科学中最基础的知识点。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需直接回忆温度对原子扩散能力的影响这一基本原理，无需复杂辨析或深度理解。", "convertible": true, "correct_option": "(b) decreases", "choice_question": "As temperature decreases, the fraction of total number of atoms that are capable of diffusive motion", "conversion_reason": "The original question is already in a multiple-choice format with clear options and a correct answer, making it directly convertible to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy for diffusion decreases", "B": "The vacancy concentration increases", "C": "The atomic vibration frequency becomes harmonic", "D": "The dislocation density reaches a critical threshold" }, "correct_answer": "A", "explanation": "The correct answer is A because at lower temperatures, the thermal energy required for atoms to overcome the activation barrier for diffusion is reduced. Option B is a cognitive bias trap - while vacancy concentration does decrease with temperature, this doesn't directly enable diffusive motion. Option C exploits harmonic approximation misconceptions in lattice dynamics. Option D is a multi-level trap combining dislocation concepts incorrectly with diffusion mechanics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4122, "question": "Do carbon-carbon composites exhibit resistance to creep?", "answer": "Carbon-carbon composites are highly resistant to creep.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个简单的陈述句，询问碳碳复合材料是否具有抗蠕变性，答案直接给出了对错判断（\"highly resistant to creep\"），符合判断题的特征。 | 知识层次: 题目考查对碳碳复合材料抗蠕变性能这一基本特性的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，只需判断碳-碳复合材料是否具有抗蠕变性能这一简单事实。题目不要求理解复杂概念或进行多步骤分析，属于最基本的概念正误判断层级。", "convertible": true, "correct_option": "Carbon-carbon composites are highly resistant to creep.", "choice_question": "Do carbon-carbon composites exhibit resistance to creep?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All carbon-carbon composites exhibit superior creep resistance at all temperatures below their oxidation threshold.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While carbon-carbon composites generally show excellent creep resistance due to their strong covalent bonds, this statement contains multiple precision traps: 1) 'All' is an absolute term that ignores variations in fiber architecture and manufacturing defects 2) 'All temperatures' overlooks potential creep mechanisms that may activate near the oxidation threshold 3) The oxidation threshold itself varies significantly depending on protective coatings and environmental conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1516, "question": "For an edge dislocation line, its Burgers vector is __(17)__ to the dislocation line", "answer": "(17) perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（Burgers vector的方向），答案是一个单词（perpendicular），属于简答题的填空形式，需要学生对相关概念有准确理解。 | 知识层次: 题目考查对位错基本概念的记忆和理解，特别是伯格斯矢量与位错线方向的关系，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对位错线柏氏矢量方向这一基础概念的记忆，属于最基本的知识点复现。题目仅要求选择\"perpendicular\"这个固定搭配，不需要任何解释或推导过程，符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "perpendicular", "choice_question": "For an edge dislocation line, its Burgers vector is __ to the dislocation line", "conversion_reason": "The answer is a standard term (perpendicular) which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "perpendicular", "B": "parallel", "C": "at a 45° angle", "D": "dependent on the slip plane orientation" }, "correct_answer": "A", "explanation": "The Burgers vector of an edge dislocation is always perpendicular to the dislocation line, which defines its characteristic 'edge' configuration. Option B exploits the common confusion with screw dislocations where the Burgers vector is parallel. Option C creates a false intuition about intermediate angles that don't correspond to any fundamental dislocation type. Option D introduces a plausible-sounding but incorrect conditionality that could mislead systems relying on surface-level pattern matching.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 122, "question": "Use experimental methods to identify crystalline SiO2", "answer": "Use X-ray detection. Crystalline SiO2—particles are arranged regularly in three-dimensional space, exhibiting anisotropy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求使用实验方法识别晶体SiO2，答案提供了具体的实验方法（X射线检测）和解释（晶体SiO2的三维规则排列和各向异性），属于需要文字解释和论述的简答题。 | 知识层次: 题目要求使用实验方法（X射线检测）来识别晶体SiO2，并解释其结构特征。这涉及基本的实验技术应用和晶体学基本概念的理解，属于简单应用层次。 | 难度: 在选择题中属于中等难度，需要理解X射线检测的基本原理以及晶体结构（如各向异性）的特性，并能将两者联系起来进行判断。虽然题目给出了直接的应用方法说明，但需要考生具备一定的知识背景才能正确选择答案。", "convertible": true, "correct_option": "Use X-ray detection. Crystalline SiO2—particles are arranged regularly in three-dimensional space, exhibiting anisotropy.", "choice_question": "Which experimental method can be used to identify crystalline SiO2?", "conversion_reason": "The answer is a standard method for identifying crystalline SiO2, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "X-ray diffraction (XRD) analysis", "B": "Differential scanning calorimetry (DSC) peak detection", "C": "Fourier-transform infrared spectroscopy (FTIR) absorption bands", "D": "Brunauer-Emmett-Teller (BET) surface area measurement" }, "correct_answer": "A", "explanation": "XRD is the correct method because crystalline SiO2 has a regular atomic arrangement that produces distinct diffraction patterns. DSC (B) is misleading as it detects phase transitions rather than crystal structure. FTIR (C) exploits the cognitive bias that all SiO2 forms show similar IR spectra, while BET (D) traps those who confuse surface properties with crystalline structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 766, "question": "Diamond, graphite, and carbon nanotubes are allotropes of carbon", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（Diamond, graphite, and carbon nanotubes are allotropes of carbon），并要求判断其正误（答案：√），这符合判断题的特征 | 知识层次: 题目考查对碳的同素异形体的基本概念的记忆和理解，属于基础概念记忆性知识 | 难度: 该题目属于基础概念正误判断，仅需记忆碳的三种同素异形体名称即可作答，无需理解或分析复杂概念，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "√", "choice_question": "Diamond, graphite, and carbon nanotubes are allotropes of carbon", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All carbon allotropes exhibit sp3 hybridization.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because only diamond exhibits sp3 hybridization among common carbon allotropes. Graphite and graphene show sp2 hybridization, while fullerenes and nanotubes display mixed hybridization states. The absolute term 'all' creates a subtle trap, as hybridization varies significantly across different carbon allotropes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1116, "question": "Both martensitic transformation and bainitic transformation are diffusionless solid-state phase transformations.", "answer": "Wrong! Martensitic transformation is a diffusionless solid-state phase transformation, while bainitic transformation involves both a diffusionless shear process and a diffusive atomic transport process, they are not the same.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目给出一个陈述（Both martensitic transformation and bainitic transformation are diffusionless solid-state phase transformations），并要求判断其正确性（答案指出该陈述是错误的）。这符合判断题的特征，即判断陈述的对错。 | 知识层次: 题目考查对马氏体相变和贝氏体相变这两种固态相变基本概念的记忆和理解，属于基础概念记忆范畴。 | 难度: 在选择题型内，该题目属于概念理解的对错判断难度等级。题目考察学生对马氏体相变和贝氏体相变的基本概念的理解，需要区分两种相变过程的差异。虽然涉及两个概念，但都属于基础概念记忆层次，解题步骤相对简单，只需判断陈述是否正确即可。因此属于等级2难度。", "convertible": true, "correct_option": "Wrong! Martensitic transformation is a diffusionless solid-state phase transformation, while bainitic transformation involves both a diffusionless shear process and a diffusive atomic transport process, they are not the same.", "choice_question": "Both martensitic transformation and bainitic transformation are diffusionless solid-state phase transformations.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect brittleness with no plastic deformation capability under any conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain fine-grained ceramics can exhibit limited plastic deformation at elevated temperatures or under high confining pressures. The use of 'all' and 'any conditions' makes this statement incorrect. Advanced ceramics like transformation-toughened zirconia can even show stress-induced phase transformations that improve toughness.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4092, "question": "For a fibrous composite with fibers that are randomly and uniformly oriented within a specific plane, when a stress is applied in any direction within the plane of the fibers, what is the reinforcement efficiency?(a) 0(b) \\frac{1}{5}(c) \\frac{3}{8}(d) \\frac{3}{4}(e) 1", "answer": "For a fibrous composite with fibers that are randomly and uniformly oriented within a specific plane,when a stress is applied in any direction within the plane of the fibers, the reinforcement efficiency is \\frac{3}{8}.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目涉及复合材料中纤维增强效率的计算，需要理解纤维随机分布时的力学行为，并应用相关公式进行计算。虽然不涉及复杂的多步计算或深度推理，但需要将概念与具体情境关联，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要理解纤维增强复合材料中纤维取向与应力方向的关系，并进行多步计算和综合分析。题目涉及中等应用层次的知识，要求考生能够将多个概念关联起来，并正确计算出增强效率。", "convertible": true, "correct_option": "(c) \\frac{3}{8}", "choice_question": "For a fibrous composite with fibers that are randomly and uniformly oriented within a specific plane, when a stress is applied in any direction within the plane of the fibers, what is the reinforcement efficiency?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option provided in the answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress (CRSS) for slip system activation", "B": "The Schmid factor for the most favorably oriented slip system", "C": "The ratio of Taylor factor to Schmid factor", "D": "The ratio of elastic modulus to shear modulus" }, "correct_answer": "A", "explanation": "The correct answer is A because the CRSS is the intrinsic material property that determines when slip begins, independent of crystal orientation. Option B is a cognitive bias trap - while the Schmid factor affects the applied stress needed to reach CRSS, it's not the fundamental determinant. Option C exploits confusion between Taylor and Schmid factors, which are related but distinct concepts. Option D uses a plausible modulus ratio to mislead those who confuse elastic and plastic deformation criteria.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 929, "question": "Briefly describe the meaning of Fick's first law, write its expression, and indicate the physical meanings of the letters.", "answer": "Fick's first law J=-D(dc/dx) J: diffusion flux, which is the amount of substance passing through a unit area per unit time, g/m²·s; D: diffusion coefficient, m²/s; dc/dx: concentration gradient, g/m⁴.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述Fick第一定律的含义，写出其表达式，并指出字母的物理意义。答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查Fick第一定律的基本定义、表达式及各符号的物理意义，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目仅要求简要描述Fick's第一定律的含义、写出其表达式并指出字母的物理意义。这属于基础概念记忆的范畴，只需直接回忆和复述定义和基本原理，无需深入分析或复杂推理。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "J=-D(dc/dx) J: diffusion flux, which is the amount of substance passing through a unit area per unit time, g/m²·s; D: diffusion coefficient, m²/s; dc/dx: concentration gradient, g/m⁴.", "choice_question": "Which of the following correctly describes Fick's first law, including its expression and the physical meanings of the letters?", "conversion_reason": "The answer is a standard description of Fick's first law, including its mathematical expression and the physical meanings of the variables, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "J=-D(dc/dx) where J is diffusion flux (g/m²·s), D is diffusion coefficient (m²/s), and dc/dx is concentration gradient (g/m⁴)", "B": "J=D(dc/dx) where J is current density (A/m²), D is dielectric constant (F/m), and dc/dx is electric field gradient (V/m²)", "C": "J=-D(dρ/dx) where J is mass flux (kg/m²·s), D is thermal diffusivity (m²/s), and dρ/dx is density gradient (kg/m⁴)", "D": "J=-D(dT/dx) where J is heat flux (W/m²), D is thermal conductivity (W/m·K), and dT/dx is temperature gradient (K/m)" }, "correct_answer": "A", "explanation": "Option A is correct as it accurately represents Fick's first law of diffusion with proper units. Option B confuses diffusion with electromagnetism by using electrical terms. Option C mimics the correct form but substitutes thermal diffusivity for diffusion coefficient, exploiting the similarity between mass and heat transfer equations. Option D is the Fourier's law of heat conduction, designed to trap those who confuse diffusion and heat transfer mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3409, "question": "Explain the meaning of the steel grade 20CrMnTi", "answer": "20CrMnTi is a carburizing steel with wc=0.20%, wMn=1%, wCr=0.3%, wC=1.1%, wTi=0.09%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释20CrMnTi钢的含义，答案提供了详细的成分说明和文字解释，符合简答题的特征。 | 知识层次: 题目考查对钢材牌号含义的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目要求考生解释20CrMnTi钢的含义，并给出具体的化学成分。这属于概念解释和描述的层次，需要考生记忆和理解钢号的命名规则及其对应的化学成分范围。虽然涉及多个元素含量的记忆，但整体上仍属于基础概念记忆的范畴，解题步骤相对直接，不需要复杂的分析或比较。因此，在选择题型内属于中等难度。", "convertible": true, "correct_option": "20CrMnTi is a carburizing steel with wc=0.20%, wMn=1%, wCr=0.3%, wC=1.1%, wTi=0.09%", "choice_question": "Which of the following correctly describes the steel grade 20CrMnTi?", "conversion_reason": "The answer is a standard and specific description of the steel grade, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "20CrMnTi is a carburizing steel with wc=0.20%, wMn=1%, wCr=0.3%, wC=1.1%, wTi=0.09%", "B": "20CrMnTi is a high-speed tool steel with wc=0.20%, wMn=1%, wCr=1.3%, wTi=0.09%", "C": "20CrMnTi is a stainless steel with wc=0.20%, wMn=1%, wCr=18%, wTi=0.09%", "D": "20CrMnTi is a low-alloy structural steel with wc=0.20%, wMn=1%, wCr=0.3%, wTi=0.09%" }, "correct_answer": "A", "explanation": "The correct answer is A because 20CrMnTi is indeed a carburizing steel with the specified composition. Option B is incorrect as it misclassifies it as a high-speed tool steel and omits the carbon content. Option C is wrong by classifying it as stainless steel with an unrealistically high chromium content. Option D is partially correct in composition but misses the critical carburizing application and the carbon content specification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4633, "question": "To what group in the periodic table would an element with atomic number 112 belong?", "answer": "From the periodic table the element having atomic number 112 would belong to group IIB. According to the periodic table, Ds, having an atomic number of 110 lies below Pt in the periodic table and in the right-most column of group VIII. Moving two columns to the right puts element 112 under \\mathrm{Hg} and in group IIB.\nThis element has been artificially created and given the name Copernicium with the symbol Cn. It was named after Nicolaus Copernicus, the Polish scientist who proposed that the earth moves around the sun (and not vice versa).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释元素112在周期表中的归属，并提供了详细的文字解释和论述，而不是简单的选择或判断。答案需要基于周期表的知识进行推理和说明，符合简答题的特征。 | 知识层次: 题目考查对元素周期表分组的基本概念的记忆和理解，仅需根据原子数定位元素在周期表中的位置，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及元素周期表的分组知识，但解题步骤相对直接，只需根据原子数定位元素在周期表中的位置即可。此外，题目提供了额外的背景信息（如元素名称和符号），但这些信息并非解题必需。因此，该题目主要考察基础概念记忆和简单应用，属于等级2的难度。", "convertible": true, "correct_option": "IIB", "choice_question": "To which group in the periodic table would an element with atomic number 112 belong?", "conversion_reason": "The answer is a standard term (group IIB) from the periodic table, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "IIB", "B": "VIIB", "C": "VIII", "D": "IB" }, "correct_answer": "A", "explanation": "The element with atomic number 112 is copernicium (Cn), which belongs to group 12 (IIB) in the periodic table. Option B (VIIB) is a cognitive bias trap, as the atomic number 112 might intuitively seem to align with higher group numbers. Option C (VIII) exploits the misconception that heavier elements might belong to transition metal groups. Option D (IB) is a professional intuition trap, as it's a common mistake to confuse group 11 (IB) with group 12 (IIB) for heavy transition metals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 132, "question": "What are the structural differences between crystalline SiO2, SiO2 glass, silica gel, and SiO2 melt?", "answer": "Crystalline SiO2—particles are arranged regularly in three-dimensional space, exhibiting anisotropy; SiO2 glass—isotropic; silica gel—loose and porous; SiO2 melt—internal structure is framework-like, with short-range order and long-range disorder.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对不同形态的SiO2进行结构差异的描述，需要文字解释和论述，答案也是以文字形式呈现的详细解释，符合简答题的特征。 | 知识层次: 题目主要考查对四种不同形态SiO2结构特点的记忆和理解，属于基础概念的记忆性知识，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及四种不同形态的SiO2，但正确选项已经明确列出了它们各自的结构特点，考生只需记忆并区分这些基本概念即可。不需要进行复杂的分析或推理，属于概念解释和描述的层次。", "convertible": true, "correct_option": "Crystalline SiO2—particles are arranged regularly in three-dimensional space, exhibiting anisotropy; SiO2 glass—isotropic; silica gel—loose and porous; SiO2 melt—internal structure is framework-like, with short-range order and long-range disorder.", "choice_question": "Which of the following correctly describes the structural differences between crystalline SiO2, SiO2 glass, silica gel, and SiO2 melt?", "conversion_reason": "The original short answer question asks for a description of structural differences, which can be converted into a multiple-choice format by providing the correct description as one of the options and asking the examinee to select the correct one.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystalline SiO2 exhibits long-range order in all dimensions, while SiO2 glass shows short-range order only. Silica gel has a mesoporous structure, and SiO2 melt displays complete structural disorder.", "B": "All forms show the same tetrahedral SiO4 units, differing only in packing density: crystalline (highest), glass (medium), melt (low), and gel (variable).", "C": "Crystalline SiO2—particles are arranged regularly in three-dimensional space, exhibiting anisotropy; SiO2 glass—isotropic; silica gel—loose and porous; SiO2 melt—internal structure is framework-like, with short-range order and long-range disorder.", "D": "The key difference lies in bond angles: crystalline (perfect 109.5°), glass (slightly distorted), melt (random), and gel (partially hydrolyzed with varying angles)." }, "correct_answer": "C", "explanation": "Correct answer C precisely describes the structural hierarchy from perfect crystalline order to complete melt disorder. Option A incorrectly states SiO2 glass has only short-range order (it has medium-range order too). Option B oversimplifies by suggesting only density differences. Option D's bond angle focus is misleading as all forms maintain similar tetrahedral angles. The traps exploit: 1) common oversimplification of glass structure (A), 2) intuitive but incorrect density-based differentiation (B), and 3) overemphasis on bond angles which are actually similar (D).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3168, "question": "Given that Cr has a body-centered cubic structure, with a lattice constant a=0.2885 nm, density ρ=7.10 g/cm³, and relative atomic mass A=51.996, calculate the number of vacancies in Cr per 10⁶ lattice points.", "answer": "The fraction of vacancies is x. From the definition of density, xρ=(2×(51.996)/(6.023×10²³)×(1−x))/(2.885³×10⁻²⁴)=7.10. Solving gives x=1−(2.885³×10⁻²⁴×7.10×6.023×10²³)/(2×51.996)≈0.0126. Therefore, the number of vacancies per 10⁶ lattice points is 10⁶×0.0126=12,600 (vacancies).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解Cr中每10⁶个晶格点的空位数，答案涉及具体的计算过程和数值结果。 | 知识层次: 题目需要进行多步计算，包括密度公式的应用、单位转换、以及解方程求解空缺浓度，涉及多个概念的综合运用和关联分析。虽然不涉及复杂的机理或创新设计，但需要一定的综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及多步计算和概念关联，包括密度定义、晶格常数、相对原子质量等知识点的综合应用。虽然题目提供了正确选项，但解题过程需要较高的综合分析能力，属于综合性计算问题。", "convertible": true, "correct_option": "12,600 vacancies", "choice_question": "Given that Cr has a body-centered cubic structure, with a lattice constant a=0.2885 nm, density ρ=7.10 g/cm³, and relative atomic mass A=51.996, what is the number of vacancies in Cr per 10⁶ lattice points?", "conversion_reason": "The calculation yields a specific numerical answer (12,600 vacancies), which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "12,600 vacancies", "B": "9,450 vacancies", "C": "15,200 vacancies", "D": "6,300 vacancies" }, "correct_answer": "A", "explanation": "The correct answer is A (12,600 vacancies) because it accurately reflects the calculation considering the BCC structure, lattice constant, density, and atomic mass of Cr. Option B (9,450 vacancies) is designed to exploit cognitive bias by providing a value close to the correct answer but derived from incorrect assumptions about atomic packing factor. Option C (15,200 vacancies) targets professional intuition by suggesting a value that might seem plausible if one overlooks the density data. Option D (6,300 vacancies) is a half-value trap, appealing to those who might make a simple division error in the final step of calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 922, "question": "What are the characteristics of the space lattice in the tetragonal crystal system?", "answer": "The lattice parameters of the tetragonal crystal system are a≠b≠c, α=β=γ=90°.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释四方晶系的空间点阵特征，答案提供了文字描述而非选择、判断或计算。 | 知识层次: 题目考查对四方晶系空间点阵特征的基本概念记忆，仅需回答晶格参数的关系（a≠b≠c, α=β=γ=90°），不涉及应用或分析过程。 | 难度: 在选择题型中，该题目仅考察对四方晶系空间点阵基本参数的定义记忆（a≠b≠c, α=β=γ=90°），属于最基础的概念性知识，无需解释或分析过程，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The lattice parameters of the tetragonal crystal system are a≠b≠c, α=β=γ=90°.", "choice_question": "Which of the following describes the characteristics of the space lattice in the tetragonal crystal system?", "conversion_reason": "The answer is a standard description of the tetragonal crystal system's lattice parameters, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The lattice parameters of the tetragonal crystal system are a≠b≠c, α=β=γ=90°", "B": "The lattice parameters of the tetragonal crystal system are a=b≠c, α=β=γ=90°", "C": "The lattice parameters of the tetragonal crystal system are a=b=c, α=β=γ=90°", "D": "The lattice parameters of the tetragonal crystal system are a=b≠c, α=β=90°, γ=120°" }, "correct_answer": "B", "explanation": "The correct answer is B because the tetragonal system is defined by a=b≠c with all angles at 90°. Option A is incorrect as it describes the orthorhombic system. Option C describes the cubic system. Option D mimics the hexagonal system's angle configuration. Advanced AIs may select A due to overgeneralizing from common crystal systems, or D by confusing angle parameters from similar systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3523, "question": "Explain the alloying principles of aluminum alloys", "answer": "Alloying principles of aluminum alloys: Commonly added elements: Cu, Mg, Zn, Si, Mn", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释铝合金的合金化原理，答案提供了常见的添加元素，但需要进一步的文字解释和论述来完整回答问题。 | 知识层次: 题目考查铝合金合金化原理的基本概念，包括常用添加元素，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型内，该题目仅要求记忆铝合金融合的基本原则和常见添加元素，属于基础概念记忆，无需深入理解或复杂分析。题目直接给出正确选项，考察的是对基本定义和分类的记忆，因此难度等级为1。", "convertible": true, "correct_option": "Alloying principles of aluminum alloys: Commonly added elements: Cu, Mg, Zn, Si, Mn", "choice_question": "Which of the following describes the alloying principles of aluminum alloys?", "conversion_reason": "The answer is a standard description of the alloying principles of aluminum alloys, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cu, Mg, Zn, Si, Mn are added primarily to form intermetallic compounds that enhance strength while maintaining ductility", "B": "Li is the most effective alloying element for increasing specific stiffness through solid solution strengthening", "C": "Sc and Zr are added to create nano-scale precipitates that stabilize the alloy at elevated temperatures", "D": "Fe and Ni are intentionally added to improve corrosion resistance through passive film formation" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental alloying principles where these elements form strengthening phases. Option B exploits the intuitive appeal of Li's lightweight properties but incorrectly states it's for stiffness. Option C uses technically correct Sc/Zr effects but in the wrong context (temperature stabilization vs grain refinement). Option D leverages the common corrosion resistance misconception by citing irrelevant elements (Fe/Ni) that actually harm Al alloys' corrosion resistance.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3090, "question": "What types can composites be divided into according to the category of matrix materials?", "answer": "Non-metal matrix composites and metal matrix composites.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据基体材料的类别对复合材料进行分类，答案需要文字解释和论述，而不是从选项中选择或判断对错，也不涉及数值计算。 | 知识层次: 题目考查复合材料根据基体材料分类的基本概念记忆，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆复合材料根据基体材料分类的基本定义（非金属基复合材料和金属基复合材料），属于最基础的概念记忆层次，无需解释或分析，因此属于等级1难度。", "convertible": true, "correct_option": "Non-metal matrix composites and metal matrix composites", "choice_question": "According to the category of matrix materials, composites can be divided into:", "conversion_reason": "The answer is a standard terminology and can be converted into a multiple-choice question format by listing possible options including the correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Non-metal matrix composites and metal matrix composites", "B": "Polymer matrix composites and ceramic matrix composites", "C": "Continuous fiber reinforced composites and particle reinforced composites", "D": "Thermoset matrix composites and thermoplastic matrix composites" }, "correct_answer": "A", "explanation": "The correct classification is based on the matrix material category (metal vs non-metal), making A correct. B incorrectly subdivides non-metal matrices only. C describes reinforcement morphology, not matrix type. D focuses on polymer subcategories, not the fundamental metal/non-metal division. Advanced AIs may overthink and select B due to its technical accuracy within a narrower context.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4337, "question": "The microstructure of an iron-carbon alloy consists of proeutectoid ferrite and pearlite; the mass fractions of these two microconstituents are 0.286 and 0.714 , respectively. Determine the concentration of carbon in this alloy.\n\\[\n\\text {", "answer": "0.55% \\text{c}", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算确定铁碳合金中的碳浓度，涉及质量分数和相图的应用，需要数值计算和公式推导。答案以具体数值形式给出。 | 知识层次: 题目需要应用铁碳相图的知识，通过多步计算来确定碳的浓度。涉及质量分数的计算和相图的理解，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳合金相图、先共析铁素体和珠光体的概念，并进行多步计算。虽然题目给出了质量分数，但需要正确应用杠杆定律和相图知识来推导碳浓度，涉及多个知识点的综合应用。", "convertible": true, "correct_option": "0.55%", "choice_question": "The microstructure of an iron-carbon alloy consists of proeutectoid ferrite and pearlite; the mass fractions of these two microconstituents are 0.286 and 0.714, respectively. What is the concentration of carbon in this alloy?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing plausible options and identifying the correct one.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.55%", "B": "0.77%", "C": "0.22%", "D": "0.40%" }, "correct_answer": "A", "explanation": "正确答案A是通过杠杆定律计算得出：Wα=0.286=(0.77-C)/(0.77-0.022)→C=0.55%。干扰项B利用认知偏差，直接给出共析成分0.77%，忽略题目中给出的相比例信息。干扰项C设计为接近纯铁碳含量，利用专业直觉陷阱，让AI可能错误认为主要相是铁素体。干扰项D是共析温度下铁素体的最大碳溶解度，属于多层次验证陷阱，表面合理但不符合题目条件。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1840, "question": "What is the relationship between △L/L and sintering time in the mass transfer process?", "answer": "(29) △L/L∝t", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释△L/L与烧结时间之间的关系，答案需要文字描述和论述，而非简单的选择、判断或计算。 | 知识层次: 题目涉及烧结过程中质量传递的基本关系，需要理解△L/L与时间t的关系，并应用相应的公式或原理进行解释。这属于中等应用层次，因为它需要将概念与公式关联起来，并进行一定的综合分析。 | 难度: 在选择题中属于中等难度，需要理解烧结过程中的质量传递概念，并能将△L/L与时间t的关系进行综合分析。题目要求考生掌握中等应用层次的知识，包括多步计算和概念关联，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "△L/L∝t", "choice_question": "What is the relationship between △L/L and sintering time in the mass transfer process?", "conversion_reason": "The answer is a standard and concise expression of the relationship, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "△L/L∝t", "B": "△L/L∝t^(1/3)", "C": "△L/L∝ln(t)", "D": "△L/L∝1/t" }, "correct_answer": "A", "explanation": "The correct relationship is linear (A) because in the initial stage of sintering, shrinkage is directly proportional to time due to viscous flow mechanisms. Option B mimics the common t^(1/3) relationship seen in diffusion-controlled processes, creating a cognitive bias. Option C exploits the logarithmic creep behavior seen in some materials. Option D reverses the intuitive relationship, playing on unit confusion traps.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3611, "question": "Suppose that FCC rhodium is produced as a 1-mm thick sheet, with the (111) plane parallel to the surface of the sheet. How many (111) interplanar spacings d_{111} thick is the sheet? See Appendix A for necessary data.", "answer": "the sheet is 4.563 × 10^{6} d_{111} spacings thick.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定1毫米厚的FCC铑片中(111)晶面间距的数量。答案给出了具体的计算结果，表明这是一个计算题。 | 知识层次: 题目需要进行多步计算，包括查找附录数据、应用晶面间距公式、单位换算等，涉及概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解FCC晶体结构、(111)晶面间距计算、单位换算等多个概念，并进行多步骤的综合计算。题目要求将1毫米厚度转换为(111)晶面间距的数量级，涉及查表数据、公式应用和单位转换，但选项已经给出计算结果，降低了部分难度。", "convertible": true, "correct_option": "the sheet is 4.563 × 10^{6} d_{111} spacings thick.", "choice_question": "Suppose that FCC rhodium is produced as a 1-mm thick sheet, with the (111) plane parallel to the surface of the sheet. How many (111) interplanar spacings d_{111} thick is the sheet? See Appendix A for necessary data.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.563 × 10^6 d_{111} spacings", "B": "2.281 × 10^6 d_{111} spacings", "C": "9.126 × 10^6 d_{111} spacings", "D": "1.141 × 10^6 d_{111} spacings" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated by dividing the 1-mm thickness by the d_{111} spacing of Rh (0.219 nm). Option B is half the correct value, exploiting a common factor-of-2 error in FCC calculations. Option C is double the correct value, targeting those who confuse (111) with (222) planes. Option D is one-fourth the correct value, designed to trap those who incorrectly consider only the atomic layer spacing rather than the full interplanar distance.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1204, "question": "During the crystallization of a solid solution, nucleation requires both (13) fluctuations and (14) fluctuations, as well as (15) fluctuations.", "answer": "(13) structure; (14) energy; (15) composition", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写特定的关键词（structure, energy, composition）来完成句子，而不是从给定的选项中选择或进行判断、计算。这种形式更接近于简答题，需要考生回忆或理解相关概念来填写空白。 | 知识层次: 题目考查对结晶过程中成核所需波动类型的基本概念记忆，包括结构、能量和成分波动，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生同时掌握结构、能量和成分三个方面的波动在结晶成核过程中的作用。这比单纯记忆一个定义或概念（等级1）要复杂一些，但不需要进行复杂的分析或推理（等级3）。考生需要理解这三个波动的基本概念及其在结晶过程中的重要性，但不需要深入阐述或应用这些概念。", "convertible": true, "correct_option": "structure; energy; composition", "choice_question": "During the crystallization of a solid solution, nucleation requires which of the following fluctuations?", "conversion_reason": "The original short answer question has a specific and standard answer that can be converted into a multiple-choice format. The correct options are clearly defined as 'structure; energy; composition', which can be presented as choices in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "composition; temperature; stress", "B": "structure; energy; composition", "C": "density; viscosity; entropy", "D": "magnetic moment; charge; spin" }, "correct_answer": "B", "explanation": "The correct answer requires understanding that solid solution nucleation fundamentally requires fluctuations in atomic arrangement (structure), thermal/chemical potential (energy), and solute distribution (composition). Option A uses plausible but incorrect 'temperature' and 'stress' which are secondary factors. Option C introduces macroscopic thermodynamic properties ('density', 'viscosity') that don't directly govern atomic-scale nucleation. Option D exploits quantum property confusion ('magnetic moment') which is irrelevant for most solid solutions. Advanced AIs may overgeneralize from liquid nucleation theories or misapply magnetic material concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 810, "question": "What is the significance of strain hardening in production?", "answer": "Strain hardening, also known as work hardening, can improve the strength and hardness of alloys. For example, cold-drawn steel wires are strengthened by utilizing the strain hardening effect. Especially for some alloys that cannot be strengthened by heat treatment, strain hardening is a very important strengthening method.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释应变硬化的意义，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目不仅要求解释应变硬化的定义（基础概念），还需要说明其在生产中的具体应用和重要性（概念关联和综合分析），涉及多步思维过程和对材料强化机制的理解。 | 难度: 在选择题中属于中等难度，题目要求理解应变硬化的概念及其在生产中的实际应用（如冷拔钢丝的强化），并需要将这一概念与合金强化方法（特别是无法通过热处理强化的合金）进行关联分析。虽然不涉及复杂计算，但需要综合理解和应用材料科学中的基本概念。", "convertible": true, "correct_option": "Strain hardening, also known as work hardening, can improve the strength and hardness of alloys. For example, cold-drawn steel wires are strengthened by utilizing the strain hardening effect. Especially for some alloys that cannot be strengthened by heat treatment, strain hardening is a very important strengthening method.", "choice_question": "What is the significance of strain hardening in production?", "conversion_reason": "The answer is a standard explanation of the concept of strain hardening, which can be used as the correct option in a multiple-choice question. The original question can remain as is for the multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases dislocation density which impedes further dislocation motion, thereby increasing yield strength", "B": "Reduces grain boundary energy through dislocation accumulation at boundaries", "C": "Creates vacancies that enhance diffusion rates for subsequent annealing processes", "D": "Induces phase transformation from austenite to martensite in all alloy systems" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental mechanism of strain hardening where increased dislocation density strengthens the material. Option B is a cognitive bias trap - while dislocations accumulate at boundaries, this doesn't reduce grain boundary energy. Option C exploits confusion between vacancies (which do increase) and their actual effect on strength. Option D is a professional intuition trap - phase transformation occurs only in specific alloy systems, not universally.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1150, "question": "What is constitutional supercooling?", "answer": "During the solidification of a solid solution alloy, the distribution of solute in the liquid phase changes, which alters the alloy's melting point. Even if the actual temperature distribution remains unchanged, the degree of supercooling at the solid-liquid interface front will vary. Therefore, the supercooling of a solid solution alloy is determined by both the changing alloy melting point and the actual temperature distribution. This type of supercooling caused by changes in liquid phase composition is called constitutional supercooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对\"constitutional supercooling\"进行文字解释和论述，答案提供了详细的定义和形成机制说明，符合简答题的特征。 | 知识层次: 题目要求解释constitutional supercooling的机理，涉及固溶体合金凝固过程中溶质分布变化对熔点的影响，以及实际温度分布与合金熔点变化之间的相互作用。这需要综合运用材料科学中的凝固理论、相变原理和热力学知识，进行推理分析和机理解释，属于较高层次的认知能力要求。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "During the solidification of a solid solution alloy, the distribution of solute in the liquid phase changes, which alters the alloy's melting point. Even if the actual temperature distribution remains unchanged, the degree of supercooling at the solid-liquid interface front will vary. Therefore, the supercooling of a solid solution alloy is determined by both the changing alloy melting point and the actual temperature distribution. This type of supercooling caused by changes in liquid phase composition is called constitutional supercooling.", "choice_question": "Which of the following best describes constitutional supercooling?", "conversion_reason": "The answer is a standard definition or description of a concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A phenomenon where the local melting point depression due to solute segregation creates a supercooled zone ahead of the solidification front", "B": "The sudden drop in temperature when a pure metal reaches its eutectic point during solidification", "C": "The cooling rate required to prevent diffusion of solute atoms during rapid solidification processes", "D": "The temperature difference between the liquidus and solidus lines in a phase diagram under non-equilibrium conditions" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes constitutional supercooling as the composition-induced supercooling ahead of the solidification front. Option B exploits confusion with pure metal solidification behavior. Option C mimics rapid solidification terminology but describes a different concept. Option D uses phase diagram terminology incorrectly by suggesting it represents supercooling rather than solidification range.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2177, "question": "What is multiple slip? What are the characteristics of its slip lines?", "answer": "Multiple slip refers to the simultaneous or alternating slip of two or more different slip systems. Their slip lines are either parallel or intersect at a certain angle. This is because certain crystal structures have specific slip systems, and there are certain angles between the slip planes and slip directions of these slip systems.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"multiple slip\"及其滑移线特征进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对\"multiple slip\"这一基础概念的定义及其特征的理解和记忆，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个概念（multiple slip的定义和特征），但正确选项已经整合了这些概念，并提供了清晰的解释。考生需要理解并记忆multiple slip的基本定义及其滑移线的特征，但不需要进行复杂的分析或比较。题目主要考察基础概念的记忆和理解，符合等级2的要求。", "convertible": true, "correct_option": "Multiple slip refers to the simultaneous or alternating slip of two or more different slip systems. Their slip lines are either parallel or intersect at a certain angle.", "choice_question": "Which of the following best describes multiple slip and its slip lines?", "conversion_reason": "The answer is a standard definition and description, which can be adapted into a multiple-choice format by presenting it as the correct option among plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Multiple slip refers to the simultaneous or alternating slip of two or more different slip systems. Their slip lines are either parallel or intersect at a certain angle.", "B": "Multiple slip occurs when a single slip system activates in multiple directions simultaneously, creating intersecting slip lines with identical crystallographic indices.", "C": "Multiple slip describes the phenomenon where slip lines from different grains align perfectly, forming continuous straight lines across grain boundaries.", "D": "Multiple slip is the sequential activation of slip systems under increasing stress, where each new slip system creates parallel slip lines to the previous ones." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines multiple slip as involving different slip systems with slip lines that may be parallel or intersecting. Option B incorrectly suggests a single slip system can activate in multiple directions. Option C wrongly implies perfect alignment across grain boundaries, which is physically improbable. Option D describes sequential rather than simultaneous/alternating slip activation, a common misconception in deformation mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4922, "question": "The magnetic flux density within a bar of some material is 0.630 tesla at an H field of 5 x 10^5 A/m. Compute the magnetic susceptibility for this material.", "answer": "2.387 x 10^-3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（磁通密度和磁场强度的关系）来求解磁化率，答案是一个具体的数值结果。 | 知识层次: 题目需要应用基本公式（磁化率与磁感应强度、磁场强度的关系）进行简单计算，属于直接套用公式的范畴，不涉及多步计算或复杂分析。 | 难度: 在选择题中属于简单难度，仅需应用基本公式（磁化率公式）并进行简单计算。题目直接给出了磁场强度和磁通密度，只需套用公式即可得出结果，无需复杂的推导或多步骤计算。", "convertible": true, "correct_option": "2.387 x 10^-3", "choice_question": "The magnetic flux density within a bar of some material is 0.630 tesla at an H field of 5 x 10^5 A/m. What is the magnetic susceptibility for this material?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.387 x 10^-3", "B": "1.256 x 10^-3", "C": "3.142 x 10^-3", "D": "4.712 x 10^-3" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the relationship B = μ0(H + M), where μ0 is the permeability of free space (4π x 10^-7 H/m). Solving for magnetization M and then susceptibility χ = M/H gives the correct value. Option B is a common error from incorrectly using μ0 as 1.256 x 10^-6 H/m. Option C is a trap for those who confuse the formula with that for relative permeability. Option D is designed to catch those who make calculation errors with π factors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4411, "question": "Describe one problem that might exist with a steel weld that was cooled very rapidly.", "answer": "If a steel weld is cooled very rapidly, martensite may form, which is very brittle. In some situations, cracks may form in the weld region as it cools.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述一个可能存在的问题，答案需要文字解释和论述，没有提供选项或要求判断对错，也不需要计算。 | 知识层次: 题目要求解释快速冷却对钢焊缝的影响，涉及马氏体形成及其脆性等概念，需要将材料科学中的相变理论与实际焊接问题关联起来进行分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解钢焊接快速冷却可能导致马氏体形成及其脆性特性，并关联到焊接区域可能产生裂纹的综合分析。题目涉及多步概念关联和综合分析，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "Martensite may form, which is very brittle, and cracks may form in the weld region.", "choice_question": "What is one problem that might exist with a steel weld that was cooled very rapidly?", "conversion_reason": "The answer is a standard concept (formation of martensite and potential cracking), which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Martensite formation leading to brittle fracture", "B": "Excessive grain growth reducing yield strength", "C": "Dissolution of carbides improving ductility", "D": "Formation of pearlite enhancing toughness" }, "correct_answer": "A", "explanation": "The correct answer is A because rapid cooling of steel welds promotes martensite formation, which is hard but brittle. Option B is incorrect because rapid cooling actually inhibits grain growth. Option C is a reversal of the actual effect - rapid cooling prevents carbide dissolution. Option D describes a slow cooling phenomenon, making it the perfect counter-intuitive trap for those who confuse cooling rates.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 989, "question": "What is the driving force of recovery recrystallization?", "answer": "The driving force of recovery recrystallization is deformation stored energy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述驱动力的概念，答案是一个简短的文字描述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查对恢复再结晶驱动力的基本概念记忆和理解，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆基础概念的定义，即恢复再结晶的驱动力是变形储存能。题目不涉及复杂的概念解释或体系阐述，仅需直接回忆知识点即可作答，属于最基础的难度等级。", "convertible": true, "correct_option": "deformation stored energy", "choice_question": "What is the driving force of recovery recrystallization?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "deformation stored energy", "B": "grain boundary curvature", "C": "chemical potential gradient", "D": "stacking fault energy" }, "correct_answer": "A", "explanation": "The correct answer is A because recovery and recrystallization are driven by the release of deformation stored energy in the material. Option B is a cognitive bias trap - grain boundary curvature drives grain growth, not recrystallization. Option C exploits the common confusion between diffusion-driven processes (chemical potential) and deformation-driven processes. Option D is a professional intuition trap - while stacking fault energy affects dislocation motion, it is not the primary driving force for recrystallization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4403, "question": "Cite advantages of forming metals by extrusion as opposed to rolling.", "answer": "The advantages of extrusion as opposed to rolling are as follows: (1) Pieces having more complicated cross-sectional geometries may be formed. (2) Seamless tubing may be produced.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举挤压成形相对于轧制的优点，答案以文字解释和论述的形式给出，没有选项或计算要求。 | 知识层次: 题目考查对金属挤压和轧制两种加工方法的基本概念记忆和理解，要求列举挤压相对于轧制的优势，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解和比较两种金属成型工艺（挤压和轧制）的具体优势。正确选项中列举了两点明确的优势，这要求考生不仅记住这些知识点，还需要能够区分和对比两种工艺的特点。因此，相较于简单的定义记忆题（等级1），该题目需要更深一层的理解和应用（等级2）。", "convertible": true, "correct_option": "Pieces having more complicated cross-sectional geometries may be formed and seamless tubing may be produced.", "choice_question": "What are the advantages of forming metals by extrusion as opposed to rolling?", "conversion_reason": "The answer provided is a standard list of advantages, which can be formatted into a single correct option for a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the advantages and providing the given advantages as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pieces having more complicated cross-sectional geometries may be formed and seamless tubing may be produced", "B": "Higher production rates and better surface finish can be achieved with extrusion", "C": "Extrusion requires lower temperatures than rolling, reducing energy consumption", "D": "The mechanical properties of extruded materials are superior in all directions" }, "correct_answer": "A", "explanation": "The correct answer A highlights the unique capability of extrusion to produce complex cross-sections and seamless tubing, which rolling cannot achieve. Option B is a cognitive bias trap - while extrusion can achieve good surface finish, rolling typically has higher production rates. Option C exploits a common misconception about temperature requirements - extrusion often requires higher temperatures than rolling. Option D is a professional intuition trap - while extrusion can improve some directional properties, it doesn't universally enhance all mechanical properties in all directions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2019, "question": "Calculate the distance between the center of a sodium ion and the next nearest Cl− ion in NaCl (given the radii of Na+ and Cl− are 0.097nm and 0.181nm, respectively).", "answer": "0.482nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算钠离子和氯离子之间的距离），并给出了具体的半径数据，解答过程需要应用公式和计算步骤，最终答案是一个具体的数值（0.482nm）。 | 知识层次: 题目要求应用基本公式（离子半径相加）进行简单计算，属于直接套用已知数据进行一步运算的范畴，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算NaCl晶体中钠离子与下一个最近氯离子之间的距离，只需应用简单的晶体几何关系（如面心立方结构中离子间距的计算公式）和给定的离子半径进行直接相加即可得出答案。解题步骤简单，无需复杂的推导或多步计算，符合等级1的定义。", "convertible": true, "correct_option": "0.482nm", "choice_question": "What is the distance between the center of a sodium ion and the next nearest Cl− ion in NaCl (given the radii of Na+ and Cl− are 0.097nm and 0.181nm, respectively)?", "conversion_reason": "The calculation question has a definite numerical answer, making it suitable for conversion into a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.482nm", "B": "0.278nm", "C": "0.390nm", "D": "0.564nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.482nm) because in the NaCl structure, the next nearest Cl− ion is located at a distance of √2 times the nearest neighbor distance (0.278nm). The nearest neighbor distance is the sum of the ionic radii (0.097nm + 0.181nm = 0.278nm), so √2 × 0.278nm ≈ 0.482nm. Option B (0.278nm) is a cognitive bias trap - it's the nearest neighbor distance but not the next nearest. Option C (0.390nm) exploits intuition for simple addition of radii with a scaling factor. Option D (0.564nm) is √3 times the nearest distance, which would be the distance to the third nearest Cl− ion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4456, "question": "For refractory ceramic materials, cite two characteristics that are adversely affected by increasing porosity.", "answer": "For refractory ceramic materials, two characteristics that are adversely affected by increasing porosity are (1) load-bearing capacity and (2) resistance to attack by corrosive materials.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举并简要说明两个特性，答案以文字解释的形式给出，不需要计算或选择，符合简答题的特征。 | 知识层次: 题目考查对耐火陶瓷材料基本特性的记忆和理解，仅需列举两个受孔隙率增加负面影响的性质，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目要求列举两个受孔隙率增加不利影响的耐火陶瓷材料特性，这仅需要记忆基础概念和基本原理，无需深入解释或复杂分析。正确选项直接提供了两个明确的特性，符合选择题型中对基础概念记忆的要求。", "convertible": true, "correct_option": "load-bearing capacity and resistance to attack by corrosive materials", "choice_question": "For refractory ceramic materials, which two characteristics are adversely affected by increasing porosity?", "conversion_reason": "The answer is a standard pair of characteristics, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermal conductivity and fracture toughness", "B": "Load-bearing capacity and resistance to attack by corrosive materials", "C": "Elastic modulus and dielectric strength", "D": "Thermal shock resistance and creep resistance" }, "correct_answer": "B", "explanation": "The correct answer is B because increasing porosity directly reduces the material's ability to bear loads (load-bearing capacity) and provides more pathways for corrosive agents to penetrate (resistance to attack). Option A is a cognitive bias trap - while thermal conductivity decreases with porosity (correct), fracture toughness actually increases due to crack deflection mechanisms (counterintuitive). Option C exploits unit confusion - elastic modulus does decrease, but dielectric strength increases due to reduced charge carrier density. Option D is a multi-level trap: thermal shock resistance improves with porosity (due to lower thermal stress), while creep resistance decreases (creating a 50/50 chance for guessing).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 884, "question": "Determine whether the following dislocation reaction can occur in FCC and confirm the reaction direction in the absence of external forces: 1/2[10−1]⇔1/6[2−1−1]+1/6[11−1]", "answer": "It can occur, to the right.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断位错反应是否可以在FCC中发生，并确认反应方向，答案给出了明确的判断（可以发生）和方向（向右），符合判断题的特征。 | 知识层次: 题目需要理解位错反应的基本原理，并能够应用这些原理来判断反应是否可行以及反应方向。这涉及到多步分析和概念关联，而不仅仅是简单的记忆或直接套用公式。 | 难度: 在选择题型中，该题目属于较高难度。需要综合运用以下能力：", "convertible": true, "correct_option": "It can occur, to the right.", "choice_question": "Determine whether the following dislocation reaction can occur in FCC and confirm the reaction direction in the absence of external forces: 1/2[10−1]⇔1/6[2−1−1]+1/6[11−1]", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The dislocation reaction 1/2[10−1]⇔1/6[2−1−1]+1/6[11−1] in FCC crystals always proceeds to the right under all temperature conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the reaction can occur to the right in the absence of external forces, the 'always' and 'all temperature conditions' make this statement false. The direction can be influenced by temperature and stress conditions. The original correct answer specifies 'in the absence of external forces', but this statement removes that critical condition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2860, "question": "Given that the yield strengths of pure iron with average grain diameters of $\\\\boldsymbol{1}\\\\mathfrak{mm}$ and $0.0625\\\\mathbf{mm}$ are 112.7MPa and 196$\\\\mathbf{MPa}$ respectively, what is the yield strength of pure iron with an average grain diameter of $0.0196\\\\mathrm{mm}$?", "answer": "$$\\\\tau={\\\\frac{G b}{\\\\lambda}}={\\\\frac{G{\\\\frac{\\\\sqrt{3}}{2}}a}{\\\\lambda}}={\\\\frac{7.9\\\\times10^{19}\\\\times{\\\\frac{\\\\sqrt{3}}{2}}\\\\times0.28\\\\times10^{-9}}{41.2\\\\times10^{-6}}}=0.465(\\\\mathrm{MPa})$$\\n\\n$$\\\\left\\\\{\\\\begin{array}{l}{{112,7=\\\\sigma_{\\\\circ}+k(1\\\\times10^{\\\\circ})^{-\\\\frac{1}{2}},}}\\\\ {{}}\\\\ {{196=\\\\sigma_{\\\\circ}+k(0.0625\\\\times10^{\\\\circ})^{-\\\\frac{1}{2}}}}\\\\end{array}\\\\right.,$$\\n\\nThe solution is\\n\\n$$\\\\begin{array}{l}{{\\\\pmb{\\\\mathscr{s}}}_{\\\\mathscr{0}}=84,935(\\\\mathrm{MPa})}\\\\ {\\\\backslash_{\\\\pmb{\\\\mathscr{k}}}=0.878}\\\\end{array}$$\\n\\nTherefore, $\\\\sigma_{\\\\ast}=84.935+0.878(0.0196\\\\times10^{-3})^{-\\\\frac{2}{2}}=283.255(\\\\mathrm{MPa})$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过给定的数据和公式进行数值计算，最终得出一个具体的数值结果。答案中包含了详细的公式推导和计算步骤，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括解方程组和公式应用，涉及Hall-Petch关系的理解和运用，需要一定的综合分析能力。 | 难度: 在选择题中属于高难度题目，需要理解Hall-Petch关系并进行多步计算。题目要求考生首先建立方程组求解材料常数，然后应用这些常数计算新的晶粒尺寸下的屈服强度。涉及对数运算、单位换算和复杂公式推导，对计算精度和概念理解要求很高。", "convertible": true, "correct_option": "283.255 MPa", "choice_question": "Given that the yield strengths of pure iron with average grain diameters of $1\\mathrm{mm}$ and $0.0625\\mathrm{mm}$ are 112.7 MPa and 196 MPa respectively, what is the yield strength of pure iron with an average grain diameter of $0.0196\\mathrm{mm}$?", "conversion_reason": "The calculation yields a specific numerical answer (283.255 MPa), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "283.255 MPa", "B": "224.8 MPa", "C": "310.4 MPa", "D": "178.6 MPa" }, "correct_answer": "A", "explanation": "正确答案A是通过Hall-Petch方程计算得出的精确结果。干扰项B设计为线性外推的常见错误结果，利用了认知偏差。干扰项C故意使用错误的指数关系计算，利用了专业直觉陷阱。干扰项D基于错误的单位换算（将mm误认为cm），利用了多层次验证陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1336, "question": "Explain the cause of the first type of temper brittleness", "answer": "The first type of temper brittleness occurs due to the precipitation of discontinuous thin-shell-like carbides along the interfaces of martensite laths or plates during martensite decomposition, which reduces the fracture strength of grain boundaries, making them the path for crack propagation and thus leading to brittle fracture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释第一类回火脆性的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释第一类回火脆性的原因，涉及马氏体分解过程中碳化物的析出行为及其对晶界断裂强度的影响，需要综合运用材料科学中的相变、断裂机理等知识进行推理分析，思维深度较高。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求深入理解马氏体分解过程中不连续薄壳状碳化物的析出机制，以及其对晶界断裂强度和裂纹扩展路径的影响。这需要综合运用材料科学知识，进行复杂的机理分析和推理，属于复杂现象的全面分析层次。在选择题型中，此类题目对知识点的掌握深度和解题能力要求极高。", "convertible": true, "correct_option": "The first type of temper brittleness occurs due to the precipitation of discontinuous thin-shell-like carbides along the interfaces of martensite laths or plates during martensite decomposition, which reduces the fracture strength of grain boundaries, making them the path for crack propagation and thus leading to brittle fracture.", "choice_question": "What is the cause of the first type of temper brittleness?", "conversion_reason": "The answer is a standard explanation that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the cause directly.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Precipitation of discontinuous thin-shell-like carbides along martensite interfaces during decomposition", "B": "Formation of continuous cementite networks at prior austenite grain boundaries", "C": "Segregation of phosphorus and sulfur impurities to grain boundaries during slow cooling", "D": "Retention of excessive retained austenite after tempering below 300°C" }, "correct_answer": "A", "explanation": "The correct answer A describes the true mechanism of the first type of temper brittleness, where discontinuous carbide precipitation weakens grain boundaries. Option B is a cognitive bias trap - it describes a real phenomenon but is characteristic of the second type of temper brittleness. Option C exploits professional intuition by presenting a grain boundary segregation mechanism that is scientifically plausible but unrelated to this specific phenomenon. Option D is a multi-level verification trap using a real microstructural concern (retained austenite) but in the wrong context for temper brittleness.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 860, "question": "Explain one of the main mechanisms of alloy strengthening from the microstructure perspective: order strengthening, and provide an example", "answer": "In ordered alloys, dislocations are superdislocations. To induce plastic deformation in the metal, both partial dislocations of the superdislocation must move simultaneously, requiring greater external stress. The bonding force between atoms of different elements is stronger than that between atoms of the same element, so the ordered arrangement of dissimilar atoms imparts higher strength to ordered alloys. For example, high-strength nickel-based superalloys contain ordered precipitate phases Ni(Ti, Al), whose strengthening mechanisms include general precipitation strengthening and order strengthening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释合金强化的主要机制之一（有序强化），并从微观结构角度进行论述，同时提供一个例子。答案以文字解释和论述的形式呈现，符合简答题的特征。 | 知识层次: 题目要求从微观结构角度解释合金强化的主要机制之一——有序强化，并提供一个实例。这需要深入理解有序合金中位错的行为、原子间相互作用以及强化机制的综合分析。此外，还需要将理论知识与实际材料（如镍基高温合金）的应用相结合，体现了对概念的深度理解和综合运用能力。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求从微观结构角度解释合金强化的主要机制之一——有序强化，并提供一个具体例子。正确选项不仅需要理解有序合金中位错（超位错）的运动机制，还需要掌握不同元素原子间结合力与同种元素原子间结合力的差异，以及这些差异如何影响合金强度。此外，选项还要求联系实际材料（镍基高温合金）的具体强化机制，涉及沉淀强化和有序强化的综合知识。这种题目需要考生具备深入的材料科学机理知识、综合分析和应用能力，以及将理论知识与实际材料案例相结合的能力，因此在选择题型中属于最复杂的分析层次。", "convertible": true, "correct_option": "In ordered alloys, dislocations are superdislocations. To induce plastic deformation in the metal, both partial dislocations of the superdislocation must move simultaneously, requiring greater external stress. The bonding force between atoms of different elements is stronger than that between atoms of the same element, so the ordered arrangement of dissimilar atoms imparts higher strength to ordered alloys. For example, high-strength nickel-based superalloys contain ordered precipitate phases Ni(Ti, Al), whose strengthening mechanisms include general precipitation strengthening and order strengthening.", "choice_question": "Which of the following correctly describes the mechanism of order strengthening in alloys from a microstructure perspective and provides an example?", "conversion_reason": "The answer is a detailed explanation of a standard concept (order strengthening) and includes an example, making it suitable for conversion to a multiple-choice format where the correct option is the detailed explanation provided.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In ordered alloys, the formation of superdislocations requires simultaneous movement of partial dislocations, increasing the critical resolved shear stress. Example: Ni3Al intermetallic compounds in nickel-based superalloys.", "B": "Order strengthening occurs when solute atoms preferentially occupy interstitial sites, creating lattice strain fields that impede dislocation motion. Example: Carbon in ferritic steels.", "C": "The mechanism involves formation of coherent precipitates with different crystal structures from the matrix, generating interfacial dislocations. Example: θ' phase in Al-Cu alloys.", "D": "It results from the difference in elastic modulus between ordered domains and the matrix, causing stress concentration at phase boundaries. Example: Pearlite in eutectoid steels." }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the superdislocation mechanism unique to ordered alloys, with Ni3Al being a classic example. Option B describes solid solution strengthening, not order strengthening. Option C describes precipitation strengthening through coherent interfaces. Option D incorrectly attributes strengthening to modulus mismatch, which is a different mechanism. The distractors exploit common confusions between different strengthening mechanisms in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3506, "question": "Compare the microstructures of HT150 and annealed 20 steel", "answer": "Microstructure: a) HT150: F+P+G (graphite); b) 20 steel: F+P.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较两种材料的微观结构，答案需要文字解释和论述，没有提供选项或要求计算，属于简答题类型。 | 知识层次: 题目主要考查对HT150和20钢两种材料微观结构的基础概念记忆，包括铁素体(F)、珠光体(P)和石墨(G)等基本组织的识别，属于材料科学中基础知识的记忆和理解层面。 | 难度: 在选择题型中，该题目要求考生记忆并区分两种不同材料的微观结构组成（HT150的F+P+G和20钢的F+P）。虽然涉及基础概念的记忆，但需要考生掌握两种材料的分类和基本组成，属于概念解释和描述的难度等级。题目不涉及复杂的概念体系或深入的分析，因此难度适中。", "convertible": true, "correct_option": "a) HT150: F+P+G (graphite); b) 20 steel: F+P", "choice_question": "Compare the microstructures of HT150 and annealed 20 steel. Which of the following correctly describes their microstructures?", "conversion_reason": "The answer is a standard description of microstructures, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "HT150: F+P+G (graphite); 20 steel: F+P", "B": "HT150: P+B; 20 steel: F+P", "C": "HT150: F+P; 20 steel: F+P+G (graphite)", "D": "HT150: F+P+G (graphite); 20 steel: F+P+Fe3C" }, "correct_answer": "A", "explanation": "HT150是灰铸铁，其典型组织为铁素体(F)+珠光体(P)+石墨(G)；而20钢是低碳钢，退火后组织为铁素体(F)+珠光体(P)。选项B错误地将HT150的组织描述为珠光体+贝氏体，忽略了石墨的存在。选项C错误地将20钢的组织加入了石墨。选项D在20钢的组织中错误添加了渗碳体(Fe3C)，而20钢退火后不会形成明显的渗碳体。这些干扰项利用了材料科学中常见的组织混淆和直觉判断错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 432, "question": "Point defects are thermodynamically stable defects, and a certain number of equilibrium defects exist in crystals at a given temperature, also known as intrinsic defects.", "answer": "(√)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述，要求判断其正确与否（√表示正确），符合判断题的特征。 | 知识层次: 题目考查点缺陷的基本概念和定义，属于基础概念的记忆和理解范畴 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆点缺陷的定义和特性即可做出正确选择，无需深入理解或分析复杂概念。", "convertible": true, "correct_option": "(√)", "choice_question": "Point defects are thermodynamically stable defects, and a certain number of equilibrium defects exist in crystals at a given temperature, also known as intrinsic defects.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All point defects in crystalline materials increase the system's Gibbs free energy under equilibrium conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most point defects increase Gibbs free energy, intrinsic (equilibrium) defects actually lower the system's free energy at finite temperatures due to the entropy contribution (ΔG = ΔH - TΔS). This is why a certain concentration of vacancies exists even in perfect crystals at equilibrium. The statement is false because it uses the absolute term 'all'.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4160, "question": "For noncubic crystals, the index of refraction is lowest in the crystallographic direction that has the(a) Highest atomic packing density(b) Lowest atomic packing density", "answer": "For noncubic crystals, the index of refraction is lowest in the crystallographic direc�on having the lowest atomic packing density.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从两个选项(a)和(b)中选择正确答案 | 知识层次: 题目考查对非立方晶体折射率与原子堆积密度关系的基本概念记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然题目涉及非立方晶体的折射率与原子堆积密度的关系，但只需理解基本概念并进行简单辨析即可作答。题目明确给出了两个对立选项（最高/最低原子堆积密度），考生只需记住\"折射率最低对应最低原子堆积密度\"这一基本原理即可正确选择，无需进行复杂的分析或计算。", "convertible": true, "correct_option": "Lowest atomic packing density", "choice_question": "For noncubic crystals, the index of refraction is lowest in the crystallographic direction that has the", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly specifies one of them as correct. Therefore, it can be directly converted to a single-choice question by keeping the question stem and identifying the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Highest atomic packing density", "B": "Lowest atomic packing density", "C": "Direction parallel to the c-axis", "D": "Direction with the highest elastic modulus" }, "correct_answer": "B", "explanation": "The correct answer is B because the refractive index is inversely related to the speed of light in the material, which is higher in directions with lower atomic packing density (less electron density to interact with photons). Option A is designed to exploit the common misconception that higher density should correlate with higher refractive index. Option C targets the intuition that principal crystallographic directions must have special optical properties. Option D introduces an unrelated material property (elastic modulus) that sounds plausible but is irrelevant to optical behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1417, "question": "What conditions must be satisfied for spontaneous dislocation reactions?", "answer": "Geometric conditions and energy conditions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释自发位错反应必须满足的条件，答案以文字形式给出，需要简要论述几何条件和能量条件。 | 知识层次: 题目考查对位错反应自发条件的基本概念记忆，仅需回答几何条件和能量条件这两个分类要点，不涉及应用或分析过程。 | 难度: 在选择题型中，该题目仅要求记忆基本的定义和分类（几何条件和能量条件），属于最基础的概念记忆层面。不需要进行概念解释或复杂体系阐述，解题步骤简单直接，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Geometric conditions and energy conditions", "choice_question": "Which of the following conditions must be satisfied for spontaneous dislocation reactions?", "conversion_reason": "The answer is a standard terminology that can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Burgers vector conservation and elastic strain energy reduction", "B": "Crystallographic alignment and temperature above recrystallization point", "C": "Geometric conditions and energy conditions", "D": "Dislocation density threshold and applied stress exceeding Peierls stress" }, "correct_answer": "C", "explanation": "The correct answer is C because spontaneous dislocation reactions fundamentally require two conditions: geometric compatibility (Burgers vector conservation) and energy reduction (the total energy after reaction must be lower). Option A is partially correct but incomplete, exploiting the AI's tendency to focus on Burgers vector conservation while overlooking the broader geometric requirements. Option B introduces temperature as a red herring, playing on the AI's association between dislocations and thermal activation. Option D combines two real but irrelevant concepts (dislocation density threshold and Peierls stress) that don't govern spontaneous reactions, creating a sophisticated-sounding but incorrect choice.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2197, "question": "Given that the recovery activation energy of a zinc single crystal is $20000\\\\mathrm{J/mol}$, removing $2\\\\%$ of the work hardening at $50^{\\\\circ}\\\\mathrm{C}$ requires $13\\\\textup{d}$; how much should the temperature be increased to remove the same amount of work hardening in $5\\\\textrm{min}$?", "answer": "When cold-plastically deformed metal undergoes recovery, if the recovery amount $R$ (in this case, the removed portion of work hardening) is constant, the relationship between the required recovery time $t$ and the recovery temperature $T$ can be expressed as $$ \\\\ln t=a+{\\\\frac{Q}{R}}{\\\\frac{1}{T}}$$ where $a$ is a constant; $\\\\boldsymbol{Q}$ is the recovery activation energy. Accordingly, we have $$ \\\\frac{t_{1}}{t_{2}}=\\\\exp\\\\biggl[-\\\\frac{Q}{R}\\\\Bigl(\\\\frac{1}{T_{2}}-\\\\frac{1}{T_{1}}\\\\Bigr)\\\\biggr]$$ From the problem statement, $$ T_{2}=-50^{\\\\circ}C=223\\\\mathrm{~K~}$$ $$ t_{2}=13~\\\\mathrm{d}=18~500~\\\\mathrm{min},\\\\quad Q=20~000~\\\\mathrm{J/mol}$$ When $t_{1}=5\\\\mathrm{min}$ is required, then $$ {\\\\frac{5}{18500}}{=}\\\\exp\\\\Bigl[-{\\\\frac{20000}{2}}\\\\Bigl({\\\\frac{1}{223}}-{\\\\frac{1}{T_{1}}}\\\\Bigr)\\\\Bigr]$$ $$ {\\\\frac{1}{T_{1}}}={\\\\frac{1}{223}}-{\\\\frac{\\\\ln3700}{10000}}$$ Therefore, the recovery temperature $$ T_{1}=273\\\\mathrm{~K~}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及激活能、温度和时间的关系，最终要求计算出一个具体的温度值。解答过程中使用了数学公式和代数运算，符合计算题的特征。 | 知识层次: 题目涉及多步计算和公式应用，需要理解恢复激活能的概念，并能够将时间、温度与激活能之间的关系进行综合分析。虽然不涉及复杂的机理分析或创新设计，但需要一定的计算能力和概念关联能力。 | 难度: 在选择题型中，这道题目属于高难度等级。题目涉及多个复杂步骤和概念的综合运用，包括：", "convertible": true, "correct_option": "273 K", "choice_question": "Given that the recovery activation energy of a zinc single crystal is $20000\\mathrm{J/mol}$, removing $2\\%$ of the work hardening at $50^{\\circ}\\mathrm{C}$ requires $13\\textup{d}$. How much should the temperature be increased to remove the same amount of work hardening in $5\\textrm{min}$? The recovery temperature should be:", "conversion_reason": "The problem is a calculation question with a specific numerical answer (273 K), which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "273 K", "B": "323 K", "C": "373 K", "D": "423 K" }, "correct_answer": "A", "explanation": "The correct answer is A (273 K) because it requires applying the Arrhenius equation to calculate the temperature increase needed to achieve the same recovery in a shorter time. The key is recognizing that the activation energy (20000 J/mol) must be used to solve for the new temperature. Options B (323 K) and C (373 K) are common mistakes from incorrect unit conversions or using the given temperature directly. Option D (423 K) is a trap for those who overestimate the temperature increase needed without proper calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4437, "question": "What point defects are possible for Al2O3 as an impurity in MgO?", "answer": "For every Al3+ ion that substitutes for Mg2+ in MgO, a single positive charge is added. Thus, in order to maintain charge neutrality, either a positive charge must be removed or a negative charge must be added. Negative charges are added by forming O2- interstitials, which are not likely to form. Positive charges may be removed by forming Mg2+ vacancies.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Al2O3作为杂质在MgO中可能形成的点缺陷类型，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目需要分析Al2O3作为杂质在MgO中可能形成的点缺陷，并解释电荷平衡机制。这涉及对点缺陷类型、电荷补偿机制的理解，以及综合分析不同缺陷形成的可能性（如O2-间隙与Mg2+空位的形成倾向）。需要较高的推理分析和机理解释能力。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解点缺陷的基本概念，还需要综合运用电荷平衡原理、晶体结构知识以及缺陷形成的能量学分析（如O2-间隙形成的不可能性）。正确选项涉及多步逻辑推理：从Al3+替代导致的电荷变化，到维持电中性的两种可能机制（阳离子空位或阴离子间隙），再到基于能量学排除其中一种机制。这种需要综合多个高阶概念并进行机理深度解释的题目，在选择题型中属于最复杂的分析层次。", "convertible": true, "correct_option": "For every Al3+ ion that substitutes for Mg2+ in MgO, a single positive charge is added. Thus, in order to maintain charge neutrality, either a positive charge must be removed or a negative charge must be added. Negative charges are added by forming O2- interstitials, which are not likely to form. Positive charges may be removed by forming Mg2+ vacancies.", "choice_question": "What point defects are possible for Al2O3 as an impurity in MgO?", "conversion_reason": "The answer is a standard explanation of the concept, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Mg2+ vacancies and O2- interstitials", "B": "Al3+ substitutions and Mg2+ interstitials", "C": "Al3+ substitutions and O2- vacancies", "D": "Mg2+ vacancies and Al3+ interstitials" }, "correct_answer": "A", "explanation": "The correct answer is A because for every Al3+ substituting Mg2+, a positive charge is added, requiring charge compensation. Mg2+ vacancies remove positive charges to maintain neutrality, while O2- interstitials are theoretically possible but highly unlikely due to their large size. Option B is incorrect because Mg2+ interstitials would increase positive charge, worsening the imbalance. Option C is incorrect because O2- vacancies would further increase positive charge. Option D is incorrect because Al3+ interstitials would require additional charge compensation mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4508, "question": "For the pair of polymers: branched and syndiotactic polypropylene with a degree of polymerization of 5000; linear and isotactic polypropylene with a degree of polymerization of 3000, do the following: (1) state whether or not it is possible to decide whether one polymer has a higher tensile modulus than the other; (2) if this is possible, note which has the higher tensile modulus and then cite the reason(s) for your choice; and (3) if it is not possible to decide, then state why.", "answer": "Yes, it is possible. The linear and isotactic polypropylene will have a greater tensile modulus. Linear polymers are more likely to crystallize that branched ones. ", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，包括判断可能性、比较两种聚合物的拉伸模量并给出理由，这符合简答题的特征。 | 知识层次: 题目要求比较两种不同结构的聚丙烯的拉伸模量，需要理解聚合物结构（支化与线性、等规与间规）对结晶度和力学性能的影响，并进行综合分析。虽然不涉及复杂计算，但需要对多个概念进行关联和比较，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合理解聚合物结构（支化与线性、等规与间规）对结晶度和力学性能的影响，并进行多角度比较分析。题目要求判断两种不同结构聚丙烯的拉伸模量高低，涉及分子链排列、结晶能力等深层次概念关联，且需在给定条件下做出明确结论并说明理由，属于多步计算和概念关联的综合分析题。", "convertible": true, "correct_option": "The linear and isotactic polypropylene will have a greater tensile modulus.", "choice_question": "For the pair of polymers: branched and syndiotactic polypropylene with a degree of polymerization of 5000; linear and isotactic polypropylene with a degree of polymerization of 3000, which one has a higher tensile modulus?", "conversion_reason": "The original question asks for a specific comparison between two polymers, and the answer provides a clear, definitive choice. This can be easily converted into a multiple-choice question by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The branched and syndiotactic polypropylene due to its higher degree of polymerization", "B": "The linear and isotactic polypropylene due to its more regular chain packing", "C": "Cannot be determined without knowing the crystallinity percentages", "D": "They would have identical tensile moduli since both are polypropylene" }, "correct_answer": "B", "explanation": "The correct answer is B because linear and isotactic polypropylene has more regular chain packing which enhances crystallinity and thus tensile modulus, despite its lower degree of polymerization. Option A is a cognitive bias trap exploiting the intuitive but incorrect assumption that higher degree of polymerization always dominates. Option C is a professional intuition trap suggesting crystallinity data is required when chain regularity is the decisive factor. Option D is a multi-level verification trap implying material identity overrides microstructure effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 666, "question": "How do crystal defects affect the diffusion coefficient?", "answer": "The diffusion rate of atoms along line defects (dislocations) and planar defects (grain boundaries and free surfaces, etc.) is much greater than that of bulk diffusion within the crystal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释晶体缺陷如何影响扩散系数，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释晶体缺陷对扩散系数的影响，涉及晶体缺陷类型（线缺陷和面缺陷）与扩散速率的关系，需要将多个概念关联起来进行分析，并比较不同类型缺陷的扩散速率差异。这属于中等应用层次，需要一定的综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解晶体缺陷（线缺陷和面缺陷）对扩散系数的影响，并比较不同缺陷类型下的扩散速率差异。题目要求考生将晶体缺陷的概念与扩散行为进行关联分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "The diffusion rate of atoms along line defects (dislocations) and planar defects (grain boundaries and free surfaces, etc.) is much greater than that of bulk diffusion within the crystal.", "choice_question": "How do crystal defects affect the diffusion coefficient?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystal defects increase diffusion by providing low-energy pathways, with dislocations and grain boundaries showing higher diffusivity than bulk", "B": "Point defects decrease diffusion coefficient by blocking atomic movement, while dislocations have negligible effect", "C": "All types of crystal defects equally reduce diffusion coefficient by introducing local strain fields", "D": "Grain boundaries decrease diffusion while vacancies increase it, creating competing effects that cancel out" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual mechanism where defects create faster diffusion pathways. Option B uses point defect confusion (they actually facilitate diffusion) and downplays dislocation effects. Option C exploits the 'strain field' intuition but falsely generalizes it to all defects. Option D creates a false competition scenario between different defect types, a common oversimplification trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2948, "question": "In ionic crystals, the diffusion rate of cations is (A) faster than that of anions (B) slower than that of anions (C) neither A nor B is correct", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项（A、B、C）中选择正确答案 | 知识层次: 题目考查离子晶体中阳离子和阴离子扩散速率的基本概念记忆，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需直接回忆离子晶体中阳离子和阴离子的扩散速率差异。题目选项明确，无需复杂分析或深度理解，属于简单概念识别。", "convertible": true, "correct_option": "A", "choice_question": "In ionic crystals, the diffusion rate of cations is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a standard single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy for cation diffusion is always lower due to smaller ionic radii", "B": "Anions diffuse faster because their larger polarizability facilitates bond breaking", "C": "Diffusion rates are identical due to charge neutrality requirements", "D": "Cations diffuse slower in oxides but faster in halides due to coordination effects" }, "correct_answer": "A", "explanation": "Correct answer A exploits the fundamental relationship between ionic size and diffusion activation energy. The key trap is option B which uses correct scientific terminology (polarizability) but draws the wrong conclusion. Option C creates a false symmetry argument appealing to charge balance, while D introduces a sophisticated but ultimately incorrect material-specific exception. Advanced AI might overthink and select D due to its apparent nuance, or be misled by B's plausible-sounding mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4787, "question": "The tensile strength and number-average molecular weight for two poly(methyl methacrylate) materials are as follows:\n\\begin{tabular}{cc}\n\\hline Tensile Strength (MPa) & Number-Average Molecular Weight (g/mol) \\\\\n\\hline 50 & 30,000 \\\\\n150 & 50,000 \\\\\n\\hline\n\\end{tabular}\nEstimate the tensile strength at a number-average molecular weight of 40,000 g/mol.", "answer": "the estimated tensile strength at a number-average molecular weight of 40,000 g/mol is 112.5 mpa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目提供了两组数据（拉伸强度和数均分子量），要求通过计算估计在特定分子量下的拉伸强度。解答过程需要数值计算和可能的插值或外推公式应用，答案也是具体的数值结果。 | 知识层次: 题目需要应用给定的数据点进行简单的线性插值计算，属于基本公式的直接应用，无需多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要理解拉伸强度与数均分子量之间的关系，但题目提供了直接的数据点，只需进行简单的线性插值计算即可得出答案。解题步骤较为直接，不涉及复杂的公式组合或深入的概念分析。", "convertible": true, "correct_option": "112.5 MPa", "choice_question": "The tensile strength and number-average molecular weight for two poly(methyl methacrylate) materials are as follows:\n\nTensile Strength (MPa) | Number-Average Molecular Weight (g/mol)\n--------------------------------|--------------------------------\n50 | 30,000\n150 | 50,000\n\nEstimate the tensile strength at a number-average molecular weight of 40,000 g/mol:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "112.5 MPa", "B": "100 MPa (linear interpolation ignoring polymer physics)", "C": "125 MPa (assuming exponential relationship)", "D": "75 MPa (confusing with yield strength)" }, "correct_answer": "A", "explanation": "The correct answer is A (112.5 MPa) calculated using the relationship σ = σ∞ - A/Mn where σ∞ is the tensile strength at infinite molecular weight. Option B is a simple linear interpolation that ignores polymer physics principles. Option C incorrectly assumes an exponential relationship. Option D confuses tensile strength with yield strength behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3420, "question": "Which commonly used alloying elements belong to the γ-phase field narrowing elements?", "answer": "Niobium, boron, and zirconium narrow the γ-phase field.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举常见的合金元素，并解释它们对γ相区的影响，需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目考查对γ相区缩小元素的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生掌握γ-phase field narrowing elements的具体分类，并能够正确识别出Niobium、boron和zirconium这三种元素。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "Niobium, boron, and zirconium narrow the γ-phase field.", "choice_question": "Which of the following commonly used alloying elements belong to the γ-phase field narrowing elements?", "conversion_reason": "The answer is a standard terminology and can be converted into a multiple-choice format by listing possible elements as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Niobium, boron, and zirconium", "B": "Chromium, molybdenum, and tungsten", "C": "Nickel, manganese, and cobalt", "D": "Aluminum, silicon, and titanium" }, "correct_answer": "A", "explanation": "The correct answer is A because niobium, boron, and zirconium are well-documented γ-phase field narrowing elements in metallurgy. Option B uses common ferrite stabilizers (chromium, molybdenum, tungsten) that actually expand the γ-phase field, exploiting the AI's potential confusion between phase field narrowing and stabilizing effects. Option C lists austenite stabilizers (nickel, manganese, cobalt) that significantly expand the γ-phase field, playing on the AI's tendency to associate common alloying elements with phase behavior. Option D includes elements with complex phase effects (aluminum, silicon, titanium) that can both narrow and expand the γ-phase depending on concentration, creating a multi-variable verification trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4883, "question": "Why must fiber materials that are drawn be thermoplastic?", "answer": "Fiber materials that are drawn must be thermoplastic because during drawing, mechanical elongation must be possible; inasmuch as thermosetting materials are, in general, hard and relatively brittle, they are not easily elongated.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么纤维材料在拉伸过程中必须是热塑性的，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目需要理解纤维材料在拉伸过程中的行为，并解释为什么必须是热塑性材料。这涉及到对热塑性和热固性材料性质的理解，以及它们在拉伸过程中的行为差异。虽然不涉及复杂的计算或深度推理，但需要对材料性质和应用场景有一定的综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解纤维材料的特性（热塑性和热固性）以及它们在拉伸过程中的行为差异。题目要求考生将材料性质与加工工艺（拉伸）关联起来，并进行综合分析。虽然不涉及复杂计算，但需要掌握多个相关概念并理解它们之间的相互作用。", "convertible": true, "correct_option": "Fiber materials that are drawn must be thermoplastic because during drawing, mechanical elongation must be possible; inasmuch as thermosetting materials are, in general, hard and relatively brittle, they are not easily elongated.", "choice_question": "Why must fiber materials that are drawn be thermoplastic?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermoplasticity enables molecular chain alignment during drawing, which is impossible in crosslinked thermosets", "B": "Thermoplastics have lower glass transition temperatures, allowing easier fiber formation", "C": "Drawing requires reversible deformation, a unique property of thermoplastic polymers", "D": "Thermosets cannot achieve the necessary crystallinity for fiber strength" }, "correct_answer": "A", "explanation": "Correct answer A addresses the fundamental requirement of molecular mobility for orientation during drawing. Distractors: B exploits temperature misconception (Tg isn't the limiting factor), C uses 'reversible deformation' which sounds plausible but is irrelevant to drawing, D falsely associates crystallinity with thermosets when amorphous thermoplastics also make good fibers. Advanced AIs might overthink and select C due to its sophisticated phrasing.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4270, "question": "To provide some perspective on the dimensions of atomic defects, consider a metal specimen that has a dislocation density of 10^4 mm^-2. Suppose that all the dislocations in 1000 mm^3 (1 cm^3) were somehow removed and linked end to end. How far (in miles) would this chain extend?", "answer": "for a dislocation density of 10^4 mm^-2, the chain would extend 6.2 miles.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定位错链的总长度并将其转换为英里单位。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式应用和简单计算，需要将位错密度转换为总长度，并进行单位换算，思维过程较为直接，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解位错密度的概念，但解题步骤相对直接，只需套用给定的位错密度和体积进行简单计算即可得出结果。不需要多个公式组合或复杂的分析过程，因此属于等级2。", "convertible": true, "correct_option": "6.2 miles", "choice_question": "To provide some perspective on the dimensions of atomic defects, consider a metal specimen that has a dislocation density of 10^4 mm^-2. Suppose that all the dislocations in 1000 mm^3 (1 cm^3) were somehow removed and linked end to end. How far (in miles) would this chain extend?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.2 miles", "B": "3.1 miles", "C": "12.4 miles", "D": "0.62 miles" }, "correct_answer": "A", "explanation": "The correct calculation involves multiplying dislocation density (10^4 mm^-2) by specimen volume (1000 mm^3) to get total dislocation length (10^7 mm = 10^4 m). Converting to miles gives 6.2 miles. Option B is half the correct value, exploiting common halving errors in dislocation calculations. Option C doubles the correct value, targeting those who confuse area and volume units. Option D is one-tenth the correct value, preying on decimal place errors common in unit conversions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4007, "question": "A structural component is fabricated from an alloy that has a plane strain fracture toughness of 45 MPa. It has been determined that this component fails at a stress of 300 MPa when the maximum length of a surface crack is 0.95 mm. What is the maximum allowable surface crack length (in mm ) without fracture for this same component exposed to a stress of 300 MPa and made from another alloy with a plane strain fracture toughness of 100.0 MPa ? The geometry factor Y is the same in both cases.", "answer": "the maximum allowable surface crack length without fracture is 1.55 mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过公式计算最大允许的表面裂纹长度，涉及数值计算和公式应用（如断裂韧性公式），答案是一个具体的数值结果（1.55 mm）。 | 知识层次: 题目需要进行多步计算，涉及断裂力学中的公式应用和不同材料参数的比较，需要理解平面应变断裂韧性和应力强度因子的关系，并进行综合分析。虽然不涉及复杂的机理分析或创新设计，但超出了简单直接套用公式的层次。 | 难度: 在选择题中属于中等难度，需要理解断裂韧性和应力强度因子的关系，并应用公式进行多步计算。题目涉及两个不同材料的比较，需要综合分析并正确应用几何因子Y的概念。虽然计算步骤较多，但在选择题型中，正确选项的提示可以帮助验证计算结果的合理性。", "convertible": true, "correct_option": "1.55 mm", "choice_question": "A structural component is fabricated from an alloy that has a plane strain fracture toughness of 45 MPa. It has been determined that this component fails at a stress of 300 MPa when the maximum length of a surface crack is 0.95 mm. What is the maximum allowable surface crack length (in mm) without fracture for this same component exposed to a stress of 300 MPa and made from another alloy with a plane strain fracture toughness of 100.0 MPa? The geometry factor Y is the same in both cases.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct option among possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.55 mm", "B": "4.69 mm", "C": "0.42 mm", "D": "2.11 mm" }, "correct_answer": "A", "explanation": "正确答案A是通过断裂力学公式K_IC=Yσ√(πa)计算得出，其中K_IC从45 MPa增加到100 MPa时，允许的裂纹长度a与K_IC的平方成正比增加。干扰项B错误地假设裂纹长度与K_IC成线性关系（45→0.95mm，100→(100/45)*0.95≈2.11mm，然后平方得到4.69mm）。干扰项C错误地认为更高韧性的材料允许更小裂纹（反向直觉陷阱）。干扰项D是线性关系的直接计算结果，忽略了平方关系。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 988, "question": "What are the common macrostructural defects in steel ingots?", "answer": "Macro defects include: macrosegregation (such as normal segregation, inverse segregation, gravity segregation), banded structure, as well as shrinkage cavities, porosity, and blowholes. Strictly speaking, it also includes the structural inhomogeneity of the three-crystal zone.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举和解释钢锭中常见的宏观结构缺陷，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目考查对钢锭宏观缺陷的基本分类和记忆，属于基础概念的记忆和理解层次，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个宏观缺陷类型，但主要是要求记忆和识别常见的宏观缺陷分类，不需要深入分析或比较。正确选项提供了明确的分类和例子，属于概念解释和描述的层次，但不需要复杂的推理或应用。", "convertible": true, "correct_option": "Macro defects include: macrosegregation (such as normal segregation, inverse segregation, gravity segregation), banded structure, as well as shrinkage cavities, porosity, and blowholes. Strictly speaking, it also includes the structural inhomogeneity of the three-crystal zone.", "choice_question": "Which of the following describes the common macrostructural defects in steel ingots?", "conversion_reason": "The answer is a standard list of terms and concepts related to macrostructural defects in steel ingots, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Macrosegregation patterns including normal segregation and inverse segregation, along with shrinkage cavities and porosity", "B": "Dislocation pile-ups at grain boundaries and vacancy clusters in the crystal lattice", "C": "Surface oxidation layers and decarburization zones extending 2-3mm deep", "D": "Thermal stress-induced microcracks with 10-50μm spacing in the columnar zone" }, "correct_answer": "A", "explanation": "Correct answer A properly identifies macrostructural defects specific to steel ingots. Option B describes microstructural defects (dislocations/vacancies), not macro defects. Option C lists surface phenomena rather than bulk macro defects. Option D mentions micro-scale features despite referencing the columnar zone. The key challenge is distinguishing true macro defects (mm-scale or larger) from microstructural features or surface effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3005, "question": "The mechanical properties of polymers are mainly determined by their degree of polymerization, crystallinity, and intermolecular forces.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对聚合物机械性能决定因素的基础概念记忆，仅需识别三个关键因素（聚合度、结晶度和分子间作用力）的正确性，不涉及应用或分析过程。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆聚合物机械性能的决定因素（聚合度、结晶度和分子间作用力）即可做出正确判断，无需深入理解或分析。", "convertible": true, "correct_option": "√", "choice_question": "The mechanical properties of polymers are mainly determined by their degree of polymerization, crystallinity, and intermolecular forces.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous polymers exhibit lower tensile strength than their crystalline counterparts under identical testing conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While crystallinity generally enhances mechanical properties, some amorphous polymers with strong intermolecular forces (like polycarbonate) can surpass the strength of certain semi-crystalline polymers. The statement's use of 'all' creates an absolute claim that doesn't account for exceptions where chain entanglement or secondary bonding in amorphous polymers provides exceptional strength.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3466, "question": "How is structural steel further subdivided?", "answer": "Structural steel is divided into: engineering structural steel and mechanical component steel. Engineering structural steel is further divided into: ordinary carbon structural steel and ordinary low-alloy steel. Mechanical component steel is divided into: carburizing steel, quenched and tempered steel, spring steel, and rolling bearing steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对结构钢的细分进行文字解释和论述，答案提供了详细的分类和说明，符合简答题的特征。 | 知识层次: 题目考查结构钢的基本分类和子分类的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个分类和细分概念，但所有信息都集中在结构钢的分类体系上，属于单一知识点的系统性记忆。考生需要准确回忆并匹配不同层级的分类关系，但不需要进行跨概念比较或复杂推理。这比单纯记忆基本定义（等级1）要求更高，但尚未达到需要整合多个复杂概念体系的难度（等级3）。", "convertible": true, "correct_option": "Structural steel is divided into: engineering structural steel and mechanical component steel. Engineering structural steel is further divided into: ordinary carbon structural steel and ordinary low-alloy steel. Mechanical component steel is divided into: carburizing steel, quenched and tempered steel, spring steel, and rolling bearing steel.", "choice_question": "How is structural steel further subdivided?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Engineering structural steel (ordinary carbon structural steel, ordinary low-alloy steel) and mechanical component steel (carburizing steel, quenched and tempered steel, spring steel, rolling bearing steel)", "B": "Ferritic steel (low carbon, medium carbon, high carbon) and austenitic steel (stainless, heat-resistant, cryogenic)", "C": "Primary structural steel (beams, columns) and secondary structural steel (fasteners, connectors)", "D": "Weldable structural steel (S-series) and non-weldable structural steel (T-series)" }, "correct_answer": "A", "explanation": "The correct classification follows the standard metallurgical categorization based on application and composition. Option B incorrectly uses phase-based classification (ferritic/austenitic) which is irrelevant for structural steel subdivision. Option C introduces a false dichotomy based on structural hierarchy rather than material properties. Option D creates a misleading distinction using non-standard weldability classifications that don't reflect actual steel categorization practices. Advanced AIs might select B due to its technically accurate but contextually incorrect phase terminology, or C due to its plausible-sounding engineering hierarchy.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3987, "question": "A hypothetical metal alloy has a grain diameter of 2.4 × 10^{-2} mm. After a heat treatment at 575^{\\circ} C for 500min, the grain diameter has increased to 7.3 × 10^{-2} mm. Compute the time required for a specimen of this same material (i.e., \\mathrm{d}_{0}=2.4 × 10^{-2}mm ) to achieve a grain diameter of 5.5 × 10^{-2}mm while being heated at 575^{\\circ} C. Assume the N grain diameter exponent has a value of 2.2.", "answer": "the time required for the specimen to achieve a grain diameter of 5.5 × 10^{-2} mm is 246min.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解时间，答案是一个具体的数值结果（246min），解答过程需要运用材料科学中的晶粒生长公式进行计算。 | 知识层次: 题目需要进行多步计算，涉及公式应用和数值求解，需要理解晶粒生长动力学的基本原理，并能够将给定的初始条件和目标条件代入公式进行计算。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力和概念关联。 | 难度: 在选择题中属于中等难度，需要理解晶粒生长动力学的基本概念，应用给定的指数关系进行多步计算，并综合分析初始条件和目标条件之间的关系。虽然题目提供了必要的参数和公式，但解题过程涉及多个步骤和数学运算，要求考生具备一定的材料科学基础和计算能力。", "convertible": true, "correct_option": "246min", "choice_question": "A hypothetical metal alloy has a grain diameter of 2.4 × 10^{-2} mm. After a heat treatment at 575^{\\circ} C for 500min, the grain diameter has increased to 7.3 × 10^{-2} mm. Compute the time required for a specimen of this same material (i.e., \\mathrm{d}_{0}=2.4 × 10^{-2}mm ) to achieve a grain diameter of 5.5 × 10^{-2}mm while being heated at 575^{\\circ} C. Assume the N grain diameter exponent has a value of 2.2. The time required is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "246 min", "B": "184 min", "C": "317 min", "D": "412 min" }, "correct_answer": "A", "explanation": "正确答案A是通过精确应用晶粒生长动力学方程计算得出。干扰项B设计为忽略N指数影响的计算结果，利用对简单线性关系的直觉偏差。干扰项C基于错误的温度补偿假设，利用材料科学中常见的Arrhenius方程误用陷阱。干扰项D通过反向应用时间-直径关系制造认知冲突，针对AI可能存在的对称性假设弱点。所有干扰项都接近真实实验可能出现的误差范围，增加辨别难度。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4908, "question": "Compute the corrosion potential for this reaction. The following corrosion data are known about the metal and solution: For Metal M: V_(MM^2+) = -0.90 V, i_0 = 10^-12 A/cm^2, beta = +0.10. For Hydrogen: V_(H^-/H_2) = 0 V, i_0 = 10^-10 A/cm^2.", "answer": "the corrosion potential for this reaction is -0.420 V.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的腐蚀数据和公式计算腐蚀电位，答案是一个具体的数值（-0.420 V），这表明解答过程涉及数值计算和公式应用。 | 知识层次: 题目需要应用腐蚀电化学的基本公式，进行多步计算，涉及腐蚀电位和电流密度的关联分析，需要理解并综合运用多个参数（如平衡电位、交换电流密度、Tafel斜率等）来求解腐蚀电位。虽然不涉及复杂的机理分析或创新设计，但计算过程需要一定的综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解腐蚀电位的计算原理，掌握能斯特方程和塔菲尔斜率的概念，并进行多步计算。题目涉及两个半反应的电位和交换电流密度，需要综合分析并正确应用公式才能得出答案。虽然选择题提供了正确选项，但解题过程仍需要较强的概念关联和计算能力。", "convertible": true, "correct_option": "-0.420 V", "choice_question": "Based on the given corrosion data for Metal M and Hydrogen, compute the corrosion potential for this reaction.", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-0.420 V", "B": "-0.380 V", "C": "-0.460 V", "D": "-0.340 V" }, "correct_answer": "A", "explanation": "The correct answer is A (-0.420 V) calculated using the mixed potential theory for corrosion. Option B (-0.380 V) is a cognitive bias trap, appearing plausible by averaging the two standard potentials. Option C (-0.460 V) exploits the intuition to simply use the more negative standard potential. Option D (-0.340 V) is designed to catch those who incorrectly prioritize the hydrogen reaction kinetics due to its higher exchange current density.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2921, "question": "Given the density of fully crystalline polytetrafluoroethylene ρ_c = 2.296 g/cm³ and the density of completely amorphous polytetrafluoroethylene ρ_a = 1.984 g/cm³, calculate the crystallinity of a polytetrafluoroethylene sample with a density of 2.26 g/cm³.", "answer": "Crystallinity φ = (ρ - ρ_a)/(ρ_c - ρ_a) = (2.26 - 1.984)/(2.296 - 1.984) = 0.276/0.312 = 0.885, thus φ = 88.5%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的密度数据和公式进行数值计算，最终得出结晶度的百分比。解答过程涉及公式应用和具体数值运算，符合计算题的特征。 | 知识层次: 题目主要考查基本公式的应用和简单计算，即利用给定的密度值直接套用结晶度计算公式进行计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目提供了所有必要的参数（ρ, ρ_c, ρ_a），并明确要求使用给定的结晶度公式进行计算。解题步骤仅涉及将数值代入公式并进行简单的算术运算，无需额外的概念理解或公式推导。这种类型的题目在选择题中属于最基础的计算题。", "convertible": true, "correct_option": "88.5%", "choice_question": "Given the density of fully crystalline polytetrafluoroethylene ρ_c = 2.296 g/cm³ and the density of completely amorphous polytetrafluoroethylene ρ_a = 1.984 g/cm³, calculate the crystallinity of a polytetrafluoroethylene sample with a density of 2.26 g/cm³. The crystallinity is:", "conversion_reason": "The calculation yields a specific numerical answer (88.5%), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "88.5%", "B": "92.3%", "C": "78.2%", "D": "64.7%" }, "correct_answer": "A", "explanation": "正确答案A通过公式(ρ-ρ_a)/(ρ_c-ρ_a)计算得出。干扰项B通过错误假设线性关系产生；干扰项C混淆了结晶度与孔隙率概念；干扰项D错误地使用了倒数关系计算。这些干扰项利用了材料科学中常见的概念混淆和直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1662, "question": "A slip plane and a (7) on it form a slip system", "answer": "(7) slip direction", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（slip direction）来补全句子，这属于需要提供特定关键词的简答题形式，而不是从多个选项中选择或判断对错 | 知识层次: 题目考查对滑移系统基本组成要素的记忆，即滑移面和滑移方向的组合，属于材料科学中晶体塑性变形的基础概念。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目仅考察对\"slip system\"基本组成的记忆（slip plane和slip direction），不需要任何解释或分析步骤。正确选项直接对应基础术语填空，属于最基础的概念记忆层次。", "convertible": true, "correct_option": "slip direction", "choice_question": "A slip plane and a (7) on it form a slip system. Which of the following correctly fills in the blank (7)?", "conversion_reason": "The answer is a standard term (slip direction), making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "slip direction", "B": "Burgers vector", "C": "twinning plane", "D": "critical resolved shear stress" }, "correct_answer": "A", "explanation": "The correct answer is A because a slip system is defined by the combination of a slip plane and a slip direction within that plane. Option B (Burgers vector) is a dislocation property, not a slip system component, exploiting confusion between dislocation theory and slip systems. Option C (twinning plane) targets confusion between slip and twinning deformation mechanisms. Option D (critical resolved shear stress) is a material property that activates slip systems, not part of their definition, creating a multi-level verification trap by requiring distinction between system definition and activation conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3942, "question": "A photomicrograph was taken of a specimen at a magnification of 100 ×, and it was determined that the average number of grains per square inch was 200 . What is this specimen's ASTM grain size number?", "answer": "the specimen's astm grain size number is 4.9.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定ASTM晶粒度数值，答案是一个具体的数值结果（4.9），这表明解答过程涉及计算步骤。 | 知识层次: 题目涉及基本的ASTM晶粒度计算公式应用，仅需一步计算即可得出结果，属于直接套用公式的简单应用层次。 | 难度: 在选择题中属于简单难度，需要应用基本公式进行计算，但仅涉及单一公式的直接套用和简单计算步骤。", "convertible": true, "correct_option": "4.9", "choice_question": "A photomicrograph was taken of a specimen at a magnification of 100 ×, and it was determined that the average number of grains per square inch was 200. What is this specimen's ASTM grain size number?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.9", "B": "5.9", "C": "3.9", "D": "6.9" }, "correct_answer": "A", "explanation": "The correct answer is A (4.9) because the ASTM grain size number (G) is calculated using the formula G = (log10N + log102) / log102, where N is the number of grains per square inch at 100× magnification. Here, N=200, so G=(log10(200)+log102)/log102 ≈ 4.9. Option B (5.9) is a cognitive bias trap, tempting those who might incorrectly recall the formula or miscalculate. Option C (3.9) exploits the common error of using linear instead of logarithmic scaling. Option D (6.9) is a professional intuition trap, mimicking typical grain size ranges but being numerically too high for this case.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1615, "question": "Schottky vacancy", "answer": "A vacancy formed by the migration of a displaced atom to the outer surface or internal interface (such as grain boundaries, etc.) is called a Schottky vacancy", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对Schottky vacancy进行文字解释和论述，答案以定义的形式给出，符合简答题的特征 | 知识层次: 题目考查Schottky vacancy的基本定义和形成过程，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别Schottky vacancy的基本定义，属于基础概念记忆层次。题目描述直接给出了定义，没有涉及复杂的概念体系或需要推理分析的内容，因此属于最简单的难度等级。", "convertible": true, "correct_option": "A vacancy formed by the migration of a displaced atom to the outer surface or internal interface (such as grain boundaries, etc.) is called a Schottky vacancy", "choice_question": "下列关于Schottky vacancy的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式，题目改写为'下列哪个是...'的形式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A vacancy formed by the migration of a displaced atom to the outer surface or internal interface (such as grain boundaries, etc.) is called a Schottky vacancy", "B": "A vacancy formed when an atom moves to an interstitial site within the crystal lattice is called a Schottky vacancy", "C": "A vacancy formed by the simultaneous removal of a cation-anion pair in ionic crystals is called a Schottky vacancy", "D": "A vacancy formed when an atom is displaced to a nearby lattice site without leaving the crystal is called a Schottky vacancy" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines Schottky vacancy as requiring atom migration to surfaces or interfaces. Option B describes a Frenkel defect, exploiting common confusion between vacancy types. Option C is a half-truth as it describes Schottky defects in ionic crystals but omits the critical surface migration aspect. Option D mimics dislocation terminology to trap those with incomplete defect knowledge.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1355, "question": "According to solidification theory, what is the fundamental principle of grain refinement through modification treatment?", "answer": "Modification treatment. That is, adding a modifier to the molten metal before pouring to promote heterogeneous nucleation and increase the number of nuclei, thereby refining the grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述改性处理的基本原理，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对凝固理论中晶粒细化机理的理解和应用，需要将改性处理与异质形核、晶粒细化等概念关联起来，并进行综合分析。虽然涉及基本原理，但需要一定的概念关联和解释能力，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及固溶理论的基本原理，要求考生掌握晶粒细化的改性处理方法，并能够理解异质形核和晶核数量增加的概念。虽然题目没有涉及复杂的计算，但需要对相关概念进行综合分析和关联，因此在选择题型中属于中等难度。", "convertible": true, "correct_option": "Adding a modifier to the molten metal before pouring to promote heterogeneous nucleation and increase the number of nuclei, thereby refining the grains.", "choice_question": "According to solidification theory, what is the fundamental principle of grain refinement through modification treatment?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Adding a modifier to promote heterogeneous nucleation by reducing the critical undercooling required for solidification", "B": "Increasing the cooling rate to achieve higher nucleation density through thermal gradients", "C": "Introducing alloying elements to lower the melting point and facilitate faster nucleation", "D": "Applying mechanical vibration during solidification to break dendrites and create more nucleation sites" }, "correct_answer": "A", "explanation": "The correct answer is A because modification treatment fundamentally works by providing additional nucleation sites through heterogeneous nucleation, which is achieved by reducing the critical undercooling needed for solidification. Option B is a strong distractor as it describes a different grain refinement mechanism (rapid cooling) that doesn't involve modification. Option C exploits the common confusion between modification and alloying effects. Option D describes mechanical grain refinement rather than chemical modification treatment.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 713, "question": "Non-stoichiometric structural defects", "answer": "The composition of certain compounds deviates from their stoichiometric ratio depending on the nature of the surrounding atmosphere and the magnitude of pressure. Such compounds are called non-stoichiometric compounds. The defects arising from the deviation in composition from the stoichiometric ratio are called non-stoichiometric structural defects.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对非化学计量结构缺陷进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征 | 知识层次: 题目考查非化学计量结构缺陷的基本定义和概念，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并描述非化学计量结构缺陷的定义及其形成原因。这比简单的定义记忆（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。考生需要能够解释概念并理解其背后的基本原理，这在选择题型中属于中等难度的要求。", "convertible": true, "correct_option": "The composition of certain compounds deviates from their stoichiometric ratio depending on the nature of the surrounding atmosphere and the magnitude of pressure. Such compounds are called non-stoichiometric compounds. The defects arising from the deviation in composition from the stoichiometric ratio are called non-stoichiometric structural defects.", "choice_question": "Which of the following best describes non-stoichiometric structural defects?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The composition of certain compounds deviates from their stoichiometric ratio depending on the nature of the surrounding atmosphere and the magnitude of pressure. Such compounds are called non-stoichiometric compounds. The defects arising from the deviation in composition from the stoichiometric ratio are called non-stoichiometric structural defects.", "B": "Defects that occur when atoms are missing from their lattice sites, creating vacancies that disrupt the perfect stoichiometry of the crystal structure.", "C": "Structural imperfections caused by the random substitution of atoms in the crystal lattice, leading to a deviation from the ideal stoichiometric formula.", "D": "Defects resulting from the thermal vibration of atoms at high temperatures, causing temporary deviations from stoichiometric ratios that become permanent upon cooling." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines non-stoichiometric structural defects as arising from compositional deviations influenced by external conditions like atmosphere and pressure. Option B describes simple vacancy defects, which are stoichiometric point defects. Option C confuses non-stoichiometry with substitutional solid solutions. Option D incorrectly attributes the phenomenon to thermal effects rather than thermodynamic equilibrium with the environment. The distractors exploit common misconceptions about defect types and their origins in material systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2098, "question": "Under equilibrium cooling conditions, a carbon steel obtains a microstructure containing 50% pearlite and 50% ferrite. What is the mass fraction of carbon in this alloy?", "answer": "x=wC=0.385", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解碳的质量分数，答案是一个具体的数值结果（x=wC=0.385），这表明解答过程涉及计算步骤。 | 知识层次: 题目需要应用杠杆定律（lever rule）进行多步计算，涉及相图中相组成与碳含量的关系，需要理解并关联多个概念（如珠光体、铁素体的形成条件及其碳含量），并进行综合分析得出结果。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图、杠杆定律的应用，并进行多步计算。题目要求考生能够将50%珠光体和50%铁素体的微观组织比例转化为碳含量计算，这需要综合运用相图知识和计算能力，属于典型的综合性计算问题。虽然题目给出了正确选项，但解题过程涉及多个概念关联和计算步骤，在选择题型中属于较复杂的题目。", "convertible": true, "correct_option": "0.385", "choice_question": "Under equilibrium cooling conditions, a carbon steel obtains a microstructure containing 50% pearlite and 50% ferrite. What is the mass fraction of carbon in this alloy?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.385", "B": "0.25", "C": "0.77", "D": "0.42" }, "correct_answer": "A", "explanation": "The correct answer is A (0.385) because it's calculated using the lever rule: pearlite fraction (0.5) × pearlite carbon content (0.77) = 0.385. Option B (0.25) exploits the common mistake of averaging ferrite (0.02) and pearlite (0.77) carbon contents. Option C (0.77) is a direct pearlite carbon content trap. Option D (0.42) is designed to catch those who incorrectly account for the eutectoid composition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 242, "question": "How should the cooling rate in the clinkering zone be controlled for high-alumina formulations (P>1.38)?", "answer": "For formulations with an alumina modulus P>1.38, when the melt cools past the KT2 boundary, the liquid phase will reabsorb C3S and precipitate C2S and CsA. Therefore, if the clinker is cooled slowly in the clinkering zone, bringing the cooling process close to equilibrium, some C3S will be reabsorbed, which is detrimental to cement quality. Hence, for formulations with P>1.38, rapid cooling should be employed during the cooling process in the clinkering zone.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对高铝配方的冷却速率控制进行解释和论述，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目涉及对高铝配方在熟料带冷却速率的控制机制的理解，需要分析冷却速率对矿物相变（C3S重新吸收和C2S、CsA析出）的影响，并解释其对水泥质量的影响。这需要综合运用材料科学和工艺知识，进行机理层面的推理和分析。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "For formulations with an alumina modulus P>1.38, when the melt cools past the KT2 boundary, the liquid phase will reabsorb C3S and precipitate C2S and CsA. Therefore, if the clinker is cooled slowly in the clinkering zone, bringing the cooling process close to equilibrium, some C3S will be reabsorbed, which is detrimental to cement quality. Hence, for formulations with P>1.38, rapid cooling should be employed during the cooling process in the clinkering zone.", "choice_question": "How should the cooling rate in the clinkering zone be controlled for high-alumina formulations (P>1.38)?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Rapid cooling to prevent C3S reabsorption and maintain cement quality", "B": "Slow cooling to allow complete crystallization of all phases", "C": "Two-stage cooling with initial rapid cooling followed by slow equilibrium cooling", "D": "Controlled cooling rate matching the KT2 boundary transition kinetics" }, "correct_answer": "A", "explanation": "The correct answer is A because rapid cooling is essential for high-alumina formulations (P>1.38) to prevent reabsorption of C3S by the liquid phase when cooling past the KT2 boundary. Option B is a cognitive bias trap - while slow cooling seems logical for crystallization, it's detrimental here. Option C is a multi-stage processing trap that appears sophisticated but fails to address the core issue. Option D is a kinetics-based trap that sounds scientifically plausible but ignores the fundamental phase equilibrium considerations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 805, "question": "What are the sufficient conditions for the formation of a critical nucleus?", "answer": "The sufficient conditions for the formation of a critical nucleus: (1) Formation of an embryo with r≥rk; (2) Acquisition of nucleation work with A≥A* (critical nucleation work).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释形成临界核的充分条件，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对临界核形成条件的记忆和理解，属于基本原理的记忆性知识，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确理解并回忆临界核形成的两个充分条件（胚胎半径达到临界值和获得临界成核功），这比单纯记忆单一概念的定义要复杂一些。题目要求考生掌握成核理论中的关键参数和条件，属于概念解释和描述的层次，但不需要进行复杂的体系阐述或比较分析。", "convertible": true, "correct_option": "Formation of an embryo with r≥rk and acquisition of nucleation work with A≥A* (critical nucleation work)", "choice_question": "What are the sufficient conditions for the formation of a critical nucleus?", "conversion_reason": "The answer is a standard concept with clear conditions that can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Formation of an embryo with r≥rk and acquisition of nucleation work with A≥A* (critical nucleation work)", "B": "Achieving supersaturation ratio S>1 and temperature below melting point", "C": "Local free energy minimum and positive curvature of the Gibbs free energy surface", "D": "Activation energy barrier overcome and chemical potential difference Δμ>0" }, "correct_answer": "A", "explanation": "The correct answer requires both size (r≥rk) and energy (A≥A*) conditions to be met simultaneously. Option B is a cognitive bias trap - while supersaturation is necessary, S>1 is insufficient alone and the melting point condition is irrelevant. Option C exploits professional intuition by describing general thermodynamic stability conditions, not specific nucleation criteria. Option D is a multi-level verification trap - while both factors contribute, they don't guarantee critical nucleus formation without the specific size requirement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 780, "question": "Liquid phase sintering refers to a sintering process in which a liquid phase is present.", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（答案用×表示错误），符合判断题的特征 | 知识层次: 题目考查对液相烧结这一基本概念的记忆和理解，属于定义性知识的判断，不涉及复杂分析或应用。 | 难度: 该题目属于基础概念正误判断题，仅需记忆液相烧结的定义即可判断正误，无需深入理解或分析多个概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "×", "choice_question": "Liquid phase sintering refers to a sintering process in which a liquid phase is present.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit ionic bonding characteristics.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics do have ionic bonding, this is not universally true. Some ceramics (like silicon carbide) exhibit primarily covalent bonding. The use of 'all' makes this statement incorrect, as it doesn't account for the diversity in ceramic material bonding types.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4339, "question": "The microstructure of an iron-carbon alloy consists of proeutectoid ferrite and pearlite; the mass fractions of these microconstituents are 0.20 and 0.80 , respectively. Determine the concentration of carbon in this alloy.", "answer": "the concentration of carbon in this alloy is 0.61% \\text{c}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算确定铁碳合金中的碳浓度，涉及质量分数和微观结构的数值计算，答案以具体数值形式给出。 | 知识层次: 题目需要应用铁碳相图的知识，进行多步计算和概念关联。首先需要理解先共析铁素体和珠光体的定义及其在相图中的位置，然后利用杠杆定律计算碳的浓度，涉及多个知识点的综合运用和中等难度的计算过程。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳合金相图、先共析铁素体和珠光体的概念，并进行多步计算（包括质量分数转换和相图定位）。虽然题目提供了关键参数，但解题过程需要综合应用相图知识和计算公式，属于典型的综合性计算问题。", "convertible": true, "correct_option": "0.61%", "choice_question": "The microstructure of an iron-carbon alloy consists of proeutectoid ferrite and pearlite; the mass fractions of these microconstituents are 0.20 and 0.80, respectively. What is the concentration of carbon in this alloy?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.61%", "B": "0.45%", "C": "0.77%", "D": "0.30%" }, "correct_answer": "A", "explanation": "The correct answer is 0.61% because the proeutectoid ferrite (0.20) and pearlite (0.80) mass fractions indicate a composition between the eutectoid (0.77%) and pure iron (0%). Using the lever rule: %C = (0.80 * 0.77%) + (0.20 * 0%) ≈ 0.61%. Option B (0.45%) exploits the common mistake of averaging the eutectoid and pure iron compositions. Option C (0.77%) is the eutectoid composition, a tempting choice for those not considering the proeutectoid ferrite. Option D (0.30%) targets the misconception of linear interpolation without accounting for the phase diagram's curvature.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2461, "question": "What is the ratio of nucleation rates between intragranular coherent disc-shaped nucleation and grain boundary incoherent double spherical cap-shaped nucleation? Given the grain diameter Π=10^-3 m, temperature T=1000 K, and Boltzmann constant k=1.38×10^-23 J/K.", "answer": "The calculation process for the nucleation rate ratio I2/I1 is as follows: I2/I1 = (d/L)exp[-(ΔGb* - ΔG*)/kT] = (10^-9/10^-3)exp[-(2.615×10^-18 - 1.26×10^-18)/(1.38×10^-23×1000)] = 2.27×10^-49. The result shows that the nucleation rate for intragranular coherent nucleation is higher than that for grain boundary incoherent nucleation.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解两种形核速率之比，答案中包含了具体的计算过程和数值结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要应用公式进行数值计算，并理解不同形核机制的能量差异。虽然计算过程较为直接，但需要综合运用多个知识点，包括形核能垒、Boltzmann分布等，属于中等应用层次。 | 难度: 在选择题型内，该题目属于高难度等级。题目涉及复杂的多步骤计算过程，包括不同形核机制的激活能差计算、玻尔兹曼因子应用以及尺寸参数比值的综合运算。需要考生同时掌握形核理论、热力学公式转换和指数运算技巧，并能正确关联多个物理概念（如相干/非相干界面、晶界形核几何因子等）。这种在选择题中要求进行多变量复杂计算和概念深度整合的题目，显著高于常规选择题的认知负荷要求。", "convertible": true, "correct_option": "2.27×10^-49", "choice_question": "What is the ratio of nucleation rates between intragranular coherent disc-shaped nucleation and grain boundary incoherent double spherical cap-shaped nucleation, given the grain diameter Π=10^-3 m, temperature T=1000 K, and Boltzmann constant k=1.38×10^-23 J/K?", "conversion_reason": "The calculation question has a specific numerical answer, which can be directly used as the correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.27×10^-49", "B": "4.89×10^-12", "C": "1.15×10^23", "D": "3.72×10^-31" }, "correct_answer": "A", "explanation": "The correct answer A (2.27×10^-49) requires precise calculation of the nucleation rate ratio considering both geometric factors and energy barriers. Option B (4.89×10^-12) is a cognitive bias trap that incorrectly assumes similar energy barriers for both nucleation types. Option C (1.15×10^23) reverses the ratio calculation direction, a common intuition error. Option D (3.72×10^-31) uses correct geometric factors but miscalculates the interfacial energy contribution.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 734, "question": "In the $\\\\mathbf{ABO}_{3}$ (perovskite) type structure, B ions occupy (a) tetrahedral voids (b) octahedral voids (c) cubic voids (d) trigonal prismatic voids", "answer": "b", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(a)-(d)中选择B离子在钙钛矿结构中所占据的空隙类型，符合选择题的特征 | 知识层次: 题目考查对钙钛矿结构中离子占据位置的基础概念记忆，属于定义和分类层面的记忆性知识 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆ABO3钙钛矿结构中B离子占据的间隙类型（八面体间隙），无需复杂分析或概念辨析。属于最简单的直接记忆类题目。", "convertible": true, "correct_option": "octahedral voids", "choice_question": "In the $\\mathbf{ABO}_{3}$ (perovskite) type structure, B ions occupy:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "octahedral voids", "B": "tetrahedral voids", "C": "cubic voids", "D": "edge-sharing tetrahedra" }, "correct_answer": "A", "explanation": "In perovskite structure (ABO₃), the B cations occupy octahedral voids formed by oxygen anions (correct answer A). Option B exploits the common confusion with spinel structures where cations occupy tetrahedral voids. Option C uses a non-standard term 'cubic voids' that sounds plausible but doesn't exist in crystallography. Option D is a sophisticated trap - while edge-sharing does occur in some perovskites, it describes polyhedral connectivity rather than site occupancy, a subtle distinction that may trip up AI models relying on pattern matching.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4121, "question": "Do carbon-carbon composites exhibit high tensile strengths at elevated temperatures?", "answer": "Carbon-carbon composites have high tensile strengths at elevated temperatures.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（\"Do carbon-carbon composites exhibit high tensile strengths at elevated temperatures?\"），而答案直接给出了判断结果（\"Carbon-carbon composites have high tensile strengths at elevated temperatures.\"）。这符合判断题的特征，即对陈述的真假进行判断。 | 知识层次: 题目考查对碳碳复合材料在高温下性能的基础概念记忆，仅需了解其基本特性即可回答，无需复杂分析或应用。 | 难度: 该题目属于基础概念记忆层次，仅需判断碳碳复合材料在高温下是否具有高拉伸强度的基本事实。题目形式为简单的是非判断，不涉及概念理解或复杂分析，符合选择题型中最基础的难度等级。", "convertible": true, "correct_option": "Carbon-carbon composites have high tensile strengths at elevated temperatures.", "choice_question": "Do carbon-carbon composites exhibit high tensile strengths at elevated temperatures?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All carbon-carbon composites maintain their room-temperature tensile strength when exposed to temperatures above 2000°C.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While carbon-carbon composites generally retain good mechanical properties at high temperatures, the absolute statement is incorrect because: 1) Different manufacturing processes create composites with varying temperature resistance; 2) Oxidation can become significant above 500°C without protective coatings; 3) Some strength degradation typically occurs at extreme temperatures due to microstructural changes. The statement fails by using 'all' and implying complete property retention.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1855, "question": "A certain powder compact has an average particle size of 2μm. After sintering to the highest temperature and holding for 0.5h, the measured grain size is 10μm. If the holding time is extended to 2h, what will the grain size be?", "answer": "d1=20μm(D2=kt)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过公式计算得出最终结果，涉及数值计算和公式应用（D2=kt），答案以具体数值形式给出。 | 知识层次: 题目需要进行多步计算，涉及晶粒生长动力学公式的应用（D²=kt），需要理解时间与晶粒尺寸的关系，并进行数值计算。虽然公式直接给出，但需要正确理解和应用公式来解决问题，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要理解晶粒生长动力学方程（D2=kt）的概念，并进行两步计算（首先根据已知条件计算k值，然后应用该值计算新的晶粒尺寸）。虽然计算步骤明确，但需要将理论知识与实际数据关联，并正确应用公式。", "convertible": true, "correct_option": "d1=20μm(D2=kt)", "choice_question": "A certain powder compact has an average particle size of 2μm. After sintering to the highest temperature and holding for 0.5h, the measured grain size is 10μm. If the holding time is extended to 2h, what will the grain size be?", "conversion_reason": "The question is a calculation problem with a specific and deterministic answer, making it suitable for conversion to a multiple-choice format. The answer provided is precise and can be directly used as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "14.1μm (assuming n=3 grain growth kinetics)", "B": "20μm (using D²=kt relationship)", "C": "40μm (linear extrapolation of grain size with time)", "D": "5.7μm (inverse time dependence for abnormal grain growth)" }, "correct_answer": "B", "explanation": "The correct answer is B because grain growth typically follows D²=kt kinetics. Option A uses n=3 kinetics which is incorrect for normal grain growth. Option C is a linear extrapolation trap that ignores the square root relationship. Option D introduces an abnormal growth mechanism not indicated in the problem. Advanced AI might incorrectly select A due to overcomplicating the kinetics or C due to linear thinking bias.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3533, "question": "How many types of titanium alloys are there?", "answer": "Titanium alloys are classified into α titanium alloys, α+β titanium alloys, and β titanium alloys", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要回答钛合金的分类类型，答案以文字解释的形式给出，不需要选择、判断或计算 | 知识层次: 题目考查钛合金的基本分类记忆，属于基础概念的记忆和理解层面，不涉及复杂分析或应用。 | 难度: 在选择题型中，此题仅需要记忆钛合金的基本分类（α、α+β、β三种类型），属于最基础的定义性知识。题目不涉及概念解释或复杂体系阐述，只需简单回忆分类名称即可作答，因此属于难度等级1。", "convertible": true, "correct_option": "α titanium alloys, α+β titanium alloys, and β titanium alloys", "choice_question": "How many types of titanium alloys are there?", "conversion_reason": "The answer is a standard classification of titanium alloys, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "α titanium alloys, α+β titanium alloys, and β titanium alloys", "B": "α titanium alloys and β titanium alloys only", "C": "α+β titanium alloys and metastable β titanium alloys", "D": "α, α+β, β, and metastable β titanium alloys" }, "correct_answer": "A", "explanation": "The correct classification of titanium alloys is based on their room-temperature microstructure: α (hexagonal close-packed), β (body-centered cubic), and their combinations (α+β). Option B is incorrect because it omits the important α+β category. Option C introduces 'metastable β' which is a subcategory, not a primary classification. Option D incorrectly treats metastable β as a separate primary type rather than a subset of β alloys. The key challenge is distinguishing between fundamental classifications (A) and specialized subcategories (C/D).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2622, "question": "Given that the atomic number of an element is 32, based on its electron configuration, identify which group it belongs to.", "answer": "Group IVA", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求基于电子构型识别元素所属的族，需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目考查对元素周期表中元素分组的基本概念的记忆和理解，仅需根据原子序数确定电子排布并对应到相应的族，属于基础概念记忆性知识。 | 难度: 在选择题中属于中等偏下难度，需要记忆原子序数与电子排布的关系，并能根据电子排布判断元素所属的族。虽然涉及基础概念记忆，但需要一定的知识应用能力，比单纯的定义记忆稍复杂。", "convertible": true, "correct_option": "Group IVA", "choice_question": "Given that the atomic number of an element is 32, based on its electron configuration, identify which group it belongs to.", "conversion_reason": "The answer is a standard term (Group IVA), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Group IVA", "B": "Group IIIA", "C": "Group VA", "D": "Group IIA" }, "correct_answer": "A", "explanation": "The element with atomic number 32 is germanium (Ge), which has the electron configuration [Ar] 3d10 4s2 4p2. This places it in Group IVA (14) of the periodic table. Option B (Group IIIA) is a common mistake due to miscounting valence electrons. Option C (Group VA) exploits the tendency to overcount p-electrons. Option D (Group IIA) targets the error of considering only s-electrons for group determination.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1940, "question": "For metals without phase transformation in the solid state, how to refine grain size through hot working without remelting?", "answer": "Perform hot working to induce dynamic recrystallization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案是一个简短的文字说明，而不是选择、判断或计算。 | 知识层次: 题目考查对动态再结晶概念的理解及其在热加工中的应用，需要将材料加工工艺与微观结构演变机制相关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解动态再结晶的概念及其与热加工的关系，并进行综合分析。题目要求考生将金属热加工与晶粒细化机制联系起来，属于中等应用层次的知识运用。", "convertible": true, "correct_option": "Perform hot working to induce dynamic recrystallization.", "choice_question": "For metals without phase transformation in the solid state, how can grain size be refined through hot working without remelting?", "conversion_reason": "The answer is a standard terminology or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Perform hot working to induce dynamic recrystallization", "B": "Apply rapid quenching after hot working to lock in fine grains", "C": "Use severe plastic deformation to accumulate dislocations", "D": "Maintain constant strain rate to prevent grain growth" }, "correct_answer": "A", "explanation": "The correct answer is A because dynamic recrystallization during hot working is the primary mechanism for grain refinement in metals without phase transformation. Option B is incorrect because rapid quenching is unnecessary and may introduce residual stresses without further grain refinement. Option C is a cognitive bias trap - while severe deformation accumulates dislocations, it's cold working that utilizes this for grain refinement, not hot working. Option D is a professional intuition trap - while controlling strain rate is important, simply maintaining it constant doesn't guarantee grain refinement without recrystallization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1877, "question": "Substances that easily form glass often have bond types such as . A. Ionic bond B. Metallic bond C. Polar covalent bond D. Covalent bond", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对玻璃形成物质键型的基础概念记忆和理解，属于基本原理的记忆性知识 | 难度: 该题目属于基础概念记忆层次，但需要考生理解不同化学键类型的特点及其与玻璃形成能力的关系。虽然选项都是常见的化学键类型，但需要考生能够区分极性共价键与其他键型的区别，并理解其在玻璃形成中的特殊作用。这比单纯记忆定义(等级1)要求更高，但尚未达到需要复杂概念区分(等级3)的程度。", "convertible": true, "correct_option": "C. Polar covalent bond", "choice_question": "Substances that easily form glass often have bond types such as .", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High entropy alloys with FCC structure", "B": "Metallic glasses with Poisson's ratio > 0.36", "C": "Bulk metallic glasses with Tg/Tm > 0.6", "D": "Amorphous polymers with Tg below room temperature" }, "correct_answer": "B", "explanation": "Correct answer is B because metallic glasses with Poisson's ratio > 0.36 exhibit exceptional plasticity due to formation of multiple shear bands. A is a trap using FCC structure which is irrelevant to plasticity. C exploits the common misconception about Tg/Tm ratio alone determining plasticity. D uses the intuitive but incorrect association between low Tg and plasticity in polymers.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4407, "question": "Compare die casting technique", "answer": "For die casting, a permanent mold is used, casting rates are high, the molten metal is forced into the mold under pressure, a two-piece mold is used, and small pieces are normally cast.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对压铸技术进行比较和描述，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对压铸技术的基本概念和特点的记忆和理解，如模具类型、铸造速率、压力注入等基础知识点，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个关于压铸技术的特点（如永久模具、高铸造速率、压力注入等），但这些都属于基础概念的记忆性知识，不需要复杂的分析或推理。正确选项整合了多个基本概念，但并未要求考生进行深层次的比较或应用，因此属于等级2的难度。", "convertible": true, "correct_option": "For die casting, a permanent mold is used, casting rates are high, the molten metal is forced into the mold under pressure, a two-piece mold is used, and small pieces are normally cast.", "choice_question": "Which of the following accurately describes the die casting technique?", "conversion_reason": "The answer is a standard description of the die casting technique, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "For die casting, a permanent mold is used, casting rates are high, the molten metal is forced into the mold under pressure, a two-piece mold is used, and small pieces are normally cast.", "B": "Die casting employs a sacrificial mold, achieves moderate production rates, relies on gravity filling, uses a multi-part mold assembly, and is primarily for large structural components.", "C": "The process utilizes reusable ceramic molds, has variable production speeds, combines pressure and vacuum filling, employs a single-piece mold design, and specializes in medium-sized castings.", "D": "In die casting, temporary sand molds are standard, production rates are low, capillary action drives metal flow, segmented molds are required, and it's exclusively for micro-castings." }, "correct_answer": "A", "explanation": "Option A is correct as it accurately describes all key die casting characteristics: permanent steel molds, high pressure injection, rapid production rates, two-part mold design, and typical small part production. Option B incorrectly describes investment casting features (sacrificial mold, gravity filling). Option C mixes elements of lost foam casting (ceramic molds) and vacuum casting. Option D describes sand casting attributes (temporary molds, low rates) but falsely attributes them to die casting.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4065, "question": "[e] Aluminum exhibits one of the highest melting points of all metals, which makes it difficult and expensive to cast.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（Aluminum exhibits one of the highest melting points of all metals, which makes it difficult and expensive to cast），并要求判断其正误（答案：F）。这是典型的判断题形式。 | 知识层次: 题目考查对铝的熔点这一基本概念的记忆和理解，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目直接陈述了一个关于铝的错误事实（铝的熔点实际上相对较低），学生只需要凭借对金属熔点的基本记忆即可判断正误。不需要进行概念理解或复杂分析，属于最基础的难度等级。", "convertible": true, "correct_option": "F", "choice_question": "[e] Aluminum exhibits one of the highest melting points of all metals, which makes it difficult and expensive to cast.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials are inherently brittle at room temperature due to their ionic bonding nature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics are brittle due to their ionic/covalent bonding, this statement is incorrect because: 1) Some ceramics like transformation-toughened zirconia exhibit significant toughness; 2) Not all ceramics have purely ionic bonding - many have mixed bonding character; 3) The statement incorrectly uses 'all' as an absolute term. The brittleness depends on microstructure and bonding type, not just the ceramic classification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1816, "question": "In the phase diagram of a ternary condensed system, if there are n boundary lines, the number of connection lines in this phase diagram must be a. (n+1) lines b. (n-1) lines c. n lines d. none", "answer": "c", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从给定的四个选项中选择一个正确答案，符合选择题的特征。 | 知识层次: 题目涉及三元相图中边界线和连接线数量的关系，需要理解相图的基本原理并应用相关规则进行推理判断，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要理解三元相图中边界线与连接线的关系，并进行综合分析判断。题目涉及多步计算和概念关联，要求考生具备较强的相图分析能力和空间想象能力。虽然给出了具体选项，但需要考生对相图结构有深入理解才能正确选择。", "convertible": true, "correct_option": "c", "choice_question": "In the phase diagram of a ternary condensed system, if there are n boundary lines, the number of connection lines in this phase diagram must be", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The number of connection lines equals the number of phases minus one", "B": "The number of connection lines is always half the number of boundary lines", "C": "The number of connection lines equals the number of invariant points", "D": "The number of connection lines is determined by the Gibbs phase rule alone" }, "correct_answer": "A", "explanation": "The correct answer is A because in ternary phase diagrams, connection lines (tie lines) connect coexisting phases in two-phase regions, and their number is always one less than the number of phases (n-1). Option B exploits the common intuition that geometric relationships should be simple fractions. Option C confuses connection lines with the topological features of the diagram. Option D misapplies the Gibbs phase rule which governs phase stability, not geometric connections.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3494, "question": "How to distinguish between 45 steel and HT150 metals through metallographic examination", "answer": "Metallographic examination", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述如何通过金相检验区分45钢和HT150金属，答案形式为文字描述而非选择、判断或计算。 | 知识层次: 题目要求通过金相检验区分45钢和HT150金属，这需要理解两种材料的基本金相组织特征，并能进行对比分析。虽然涉及基础概念，但需要将多个知识点关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解金属材料的基本特性（如45钢和HT150铸铁的组织结构差异），掌握金相检验的基本原理和方法，并能综合分析金相组织特征来区分两种材料。这涉及多个概念的关联应用，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "Metallographic examination", "choice_question": "Which method can be used to distinguish between 45 steel and HT150 metals?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metallographic examination of pearlite formation patterns", "B": "Measuring thermal conductivity at 500°C", "C": "Comparing Brinell hardness values at room temperature", "D": "X-ray diffraction analysis of crystal structure" }, "correct_answer": "A", "explanation": "Metallographic examination is the only method that can directly reveal the distinct pearlite formation patterns between medium-carbon 45 steel and gray cast iron HT150. Option B exploits thermal conductivity misconception (both show similar values at high temps). Option C uses hardness overlap (HB range 150-200 for both). Option D is a multi-level trap - while XRD can distinguish, it requires advanced phase analysis beyond basic crystal structure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1051, "question": "Calculate the graphite content in Fe-3.6%C alloy", "answer": "The graphite content is: wG = (3.6 - 0.68) / (100 - 0.68) × 100% ≈ 2.94%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过计算得出的具体数值结果。 | 知识层次: 题目涉及基本的公式应用和简单计算，只需直接套用给定的公式进行计算即可，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要套用特定公式进行百分比计算，但解题步骤明确且直接，仅涉及单一公式的简单应用和基础代数运算，无需多步骤推导或复杂概念整合。相比等级1的直接计算题稍复杂，但远低于等级3的多公式组合难度。", "convertible": true, "correct_option": "2.94%", "choice_question": "What is the graphite content in Fe-3.6%C alloy?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice in a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.94%", "B": "3.6%", "C": "1.8%", "D": "4.2%" }, "correct_answer": "A", "explanation": "The correct answer is A (2.94%) because in Fe-3.6%C alloy, the graphite content is calculated by considering the eutectic composition (4.3% C) and applying the lever rule. The graphite fraction is (3.6-0.02)/(4.3-0.02) ≈ 0.835, then 0.835*(4.3-3.6) ≈ 2.94%. Option B (3.6%) is a trap for those who mistakenly assume all carbon forms graphite. Option C (1.8%) exploits the common error of halving the total carbon content. Option D (4.2%) is designed to catch those who confuse the eutectic composition with the graphite content.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1651, "question": "Line defect", "answer": "One-dimensional defect, with very small dimensions in the other two directions, for example, dislocation", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Line defect\"进行解释和论述，答案提供了文字解释和例子，符合简答题的特征 | 知识层次: 题目考查基本概念的记忆和理解，即线缺陷的定义和例子，属于材料科学中的基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"Line defect\"的基本定义和典型例子（如位错）。属于基础概念记忆层次，无需复杂分析或推理，仅需直接回忆相关知识即可作答。", "convertible": true, "correct_option": "One-dimensional defect, with very small dimensions in the other two directions, for example, dislocation", "choice_question": "Which of the following best describes a line defect?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct definition as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "One-dimensional defect, with very small dimensions in the other two directions, for example, dislocation", "B": "Two-dimensional defect characterized by abrupt changes in atomic arrangement, such as grain boundaries", "C": "Point defect involving substitutional impurities in the crystal lattice", "D": "Three-dimensional defect formed by vacancy clusters exceeding critical size" }, "correct_answer": "A", "explanation": "The correct answer is A because line defects are indeed one-dimensional defects with negligible dimensions in the other two directions, with dislocations being the classic example. Option B describes a two-dimensional defect (surface defect), which is a common confusion point. Option C describes a point defect, exploiting the tendency to mix defect dimensionality classifications. Option D describes a volume defect, using technically accurate terminology but for the wrong defect type.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 368, "question": "During the deformation of polycrystals, under a certain amount of deformation, why do some grains exhibit large slip amounts while others show small slip amounts?", "answer": "When the orientation factor of a slip system in a grain relative to the force axis is large, slip initiates first; when the orientation factor is small, slip initiates later, resulting in different deformation amounts among grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释多晶体变形过程中不同晶粒滑移量差异的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及多晶变形过程中不同晶粒滑移量的差异，需要理解取向因子对滑移系统启动的影响机制，并进行综合分析。这需要综合运用晶体学、塑性变形原理等知识，进行推理分析和机理解释，属于较高层次的认知要求。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解晶体变形的基本概念，还需要综合运用取向因子、滑移系统等专业知识，进行复杂的推理分析。正确选项涉及多步骤的机理解释（取向因子大小与滑移启动顺序的关系），并需要将微观机制与宏观变形现象联系起来。这种深度分析和综合推理能力的要求明显高于普通选择题，属于复杂现象全面分析的范畴。", "convertible": true, "correct_option": "When the orientation factor of a slip system in a grain relative to the force axis is large, slip initiates first; when the orientation factor is small, slip initiates later, resulting in different deformation amounts among grains.", "choice_question": "During the deformation of polycrystals, under a certain amount of deformation, why do some grains exhibit large slip amounts while others show small slip amounts?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be kept as is for the choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Due to differences in the Schmid factor of individual grains leading to varying resolved shear stresses", "B": "Because grains with higher elastic modulus deform less under the same stress", "C": "Random statistical variation in dislocation density distribution among grains", "D": "Differential thermal expansion coefficients causing uneven deformation" }, "correct_answer": "A", "explanation": "The correct answer is A because the Schmid factor determines the resolved shear stress on slip systems, causing orientation-dependent deformation. Option B is incorrect as elastic modulus affects elastic, not plastic deformation. Option C is misleading because dislocation density differences are secondary effects, not primary causes. Option D is irrelevant as thermal effects are negligible in typical cold working conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2012, "question": "Analyze the type of solid solution formed by C in α-Fe and γ-Fe, their locations, and the solubility (mole fraction). The atomic radii of the elements are as follows: C: 0.077 nm, α-Fe: 0.124 nm, γ-Fe: 0.126 nm", "answer": "In α-Fe, C forms an interstitial solid solution, with the maximum solubility (mole fraction) reaching 0.0218×10^-2 at 727°C and decreasing to 0.006×10^-2 at room temperature. The location of C in α-Fe is mostly at the octahedral interstitial centers. In γ-Fe, C forms an interstitial solid solution located at the octahedral interstitial centers, with the maximum solubility (mass fraction) being 2.11×10^-2.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析碳在α-Fe和γ-Fe中形成的固溶体类型、位置以及溶解度（摩尔分数），需要详细的文字解释和论述，而不是简单的选择、判断或计算。答案也提供了详细的解释和论述，符合简答题的特征。 | 知识层次: 题目需要分析碳在α-Fe和γ-Fe中的固溶体类型、位置以及溶解度，涉及多步概念关联和综合分析。虽然题目给出了原子半径等基础数据，但需要理解间隙固溶体的形成条件、不同温度下的溶解度变化以及间隙位置的选择等中等复杂度的知识点。 | 难度: 在选择题型内，该题目属于较高难度。题目要求考生不仅理解间隙固溶体的基本概念，还需要掌握碳在α-Fe和γ-Fe中的具体位置（八面体间隙中心）以及不同温度下的溶解度变化。此外，题目还涉及原子半径数据的隐含应用，需要考生进行多步计算和综合分析。这些要求超出了简单记忆或单一概念的应用，属于多角度分析论述的范畴。", "convertible": true, "correct_option": "In α-Fe, C forms an interstitial solid solution, with the maximum solubility (mole fraction) reaching 0.0218×10^-2 at 727°C and decreasing to 0.006×10^-2 at room temperature. The location of C in α-Fe is mostly at the octahedral interstitial centers. In γ-Fe, C forms an interstitial solid solution located at the octahedral interstitial centers, with the maximum solubility (mass fraction) being 2.11×10^-2.", "choice_question": "Analyze the type of solid solution formed by C in α-Fe and γ-Fe, their locations, and the solubility (mole fraction). The atomic radii of the elements are as follows: C: 0.077 nm, α-Fe: 0.124 nm, γ-Fe: 0.126 nm. Which of the following statements is correct?", "conversion_reason": "The original question is a short answer question that requires a detailed explanation. However, the answer is a standard and specific description that can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct statement among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In α-Fe, C forms an interstitial solid solution, with the maximum solubility (mole fraction) reaching 0.0218×10^-2 at 727°C and decreasing to 0.006×10^-2 at room temperature. The location of C in α-Fe is mostly at the octahedral interstitial centers. In γ-Fe, C forms an interstitial solid solution located at the octahedral interstitial centers, with the maximum solubility (mass fraction) being 2.11×10^-2.", "B": "In both α-Fe and γ-Fe, C forms substitutional solid solutions due to the relatively small size difference between C and Fe atoms. The solubility is higher in γ-Fe because of its more open FCC structure.", "C": "C forms interstitial solid solutions in both α-Fe and γ-Fe, but the solubility is higher in α-Fe (BCC structure) because it has more tetrahedral interstitial sites than γ-Fe (FCC structure).", "D": "The solubility of C in γ-Fe is higher than in α-Fe because C atoms preferentially occupy the larger tetrahedral interstitial sites in γ-Fe's FCC structure, while in α-Fe's BCC structure they are restricted to smaller octahedral sites." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the interstitial nature of C in both α-Fe and γ-Fe, the octahedral site preference, and the temperature-dependent solubility differences. Option B incorrectly suggests substitutional solution due to size similarity, exploiting the common misconception that small solutes always form interstitial solutions. Option C reverses the solubility trend between α-Fe and γ-Fe, playing on the intuitive but incorrect assumption that BCC should have higher solubility. Option D contains a half-truth about higher γ-Fe solubility but incorrectly identifies the preferred interstitial site type, exploiting the complex relationship between crystal structure and interstitial site geometry that even advanced AI models may misjudge.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4137, "question": "Which of the following materials display(s) antiferromagnetic behavior?(a) Aluminum oxide(b) Copper(c) Aluminum(d) Titanium(e) Iron ( \\alpha ferrite)(f) Nickel(g) MnO\nh) \\mathrm{Fe}_{3} \\mathrm{O}_{4}\ni) \\mathrm{NiFe}_{2} \\mathrm{O}_{4}", "answer": "(\\mathrm{MnO} is an antiferromagnetic material.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择显示反铁磁行为的材料，符合选择题的特征 | 知识层次: 题目考查对反铁磁性材料的基本概念和分类的记忆，只需识别哪些材料具有反铁磁性行为，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目需要考生理解并辨析不同材料的磁性行为，特别是区分反铁磁性与其他磁性（如铁磁性、顺磁性等）。虽然题目提供了多个选项，但正确选项（MnO）是典型的反铁磁性材料，属于基础概念记忆的范畴。考生需要掌握材料分类的基本原理，但不需要复杂的分析或深度理解，因此属于中等难度（等级2）。", "convertible": true, "correct_option": "MnO", "choice_question": "Which of the following materials displays antiferromagnetic behavior?", "conversion_reason": "The original question is already in a multiple-choice format, and it can be converted to a single-choice question by selecting the correct option from the given choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cr₂O₃", "B": "Fe₃O₄ (magnetite)", "C": "NiFe₂O₄ (nickel ferrite)", "D": "CoO" }, "correct_answer": "A", "explanation": "Cr₂O₃ is a well-known antiferromagnetic material with a Néel temperature of 307K. The key difficulty lies in distinguishing it from ferrimagnetic materials (B and C) which also contain transition metals. Fe₃O₄ (B) is a classic ferrimagnet due to its inverse spinel structure, while NiFe₂O₄ (C) is also ferrimagnetic. CoO (D) is antiferromagnetic but has a more complex magnetic structure than Cr₂O₃, making it a less straightforward example. The trap is that all options contain magnetic transition metals, requiring deep knowledge of their specific magnetic ordering.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3865, "question": "A steel contains 96% \\gamma and 4% \\mathrm{Fe}_{3} C at 800^{\\circ} C. Estimate the carbon content of the steel.\n\\[\n\\begin{array}{l}\n\\text {", "answer": "the carbon content of the steel is 1.15% C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算来估计钢的碳含量，需要使用给定的成分比例和可能的相图或公式进行计算。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及相图的应用和碳含量的估算，需要理解相图的基本原理并进行综合分析。虽然计算过程不算复杂，但需要关联多个概念和步骤，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解相图概念并进行多步计算。题目要求根据给定的γ相和Fe3C比例估算钢的碳含量，这涉及到杠杆定律的应用和相图知识的综合运用。虽然计算步骤明确，但需要考生对相图有较深的理解并能正确应用相关公式，属于综合性计算问题。", "convertible": true, "correct_option": "1.15% C", "choice_question": "A steel contains 96% γ and 4% Fe₃C at 800°C. What is the estimated carbon content of the steel?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.15% C", "B": "0.77% C", "C": "4.0% C", "D": "0.96% C" }, "correct_answer": "A", "explanation": "正确答案A(1.15% C)通过杠杆定律计算得出：在800°C时，γ相含0.025% C，Fe₃C含6.67% C，根据两相比例96%和4%计算加权平均。干扰项B(0.77% C)利用共析点碳含量的直觉陷阱；C(4.0% C)直接误用Fe₃C百分比；D(0.96% C)混淆了γ相百分比与碳含量。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2613, "question": "The atomic number of chromium is 24, and it has a total of 4 isotopes: 4.31% of Cr atoms contain 26 neutrons, 83.76% contain 28 neutrons, 9.55% contain 29 neutrons, and 2.38% contain 30 neutrons. Calculate the relative atomic mass of chromium.", "answer": "$A{\\tau}=0.0431\\times(24+26)+0.8376\\times(24+28)+0.0955\\times(24+29)$ $+0.0238\\times(24+30)=52.057$ 1-6 $A", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铬的相对原子质量，答案给出了具体的计算过程和结果。 | 知识层次: 题目主要考查基本公式应用和简单计算，涉及同位素丰度和相对原子质量的计算，属于直接套用公式的简单应用层次。 | 难度: 在选择题中属于简单难度，题目要求应用基本公式（相对原子质量计算）并进行简单计算。虽然涉及多个同位素的比例和计算步骤，但每一步都是直接套用公式，没有复杂的推理或分析过程。", "convertible": true, "correct_option": "52.057", "choice_question": "The atomic number of chromium is 24, and it has a total of 4 isotopes: 4.31% of Cr atoms contain 26 neutrons, 83.76% contain 28 neutrons, 9.55% contain 29 neutrons, and 2.38% contain 30 neutrons. What is the relative atomic mass of chromium?", "conversion_reason": "The calculation yields a specific numerical answer, making it suitable for conversion into a multiple-choice question format where the correct option is the calculated value.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "52.057", "B": "52.000", "C": "51.996", "D": "52.123" }, "correct_answer": "A", "explanation": "The correct answer is A (52.057) because it accurately calculates the weighted average of chromium's isotopes considering their natural abundances. Option B (52.000) is a common mistake where one might incorrectly assume the most abundant isotope (Cr-52 with 83.76% abundance) represents the entire element. Option C (51.996) is the atomic mass of chromium's most stable isotope (Cr-52) but ignores isotopic distribution. Option D (52.123) is a distracter that overestimates the contribution of the heaviest isotope (Cr-54 with 2.38% abundance). Advanced AIs might fail by either over-simplifying the calculation or misweighting the isotopic contributions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1924, "question": "Please explain what a perfect dislocation is", "answer": "Perfect dislocation: The Burgers vector is an integer multiple of the lattice vector.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释\"perfect dislocation\"的概念，需要文字解释和论述，答案也是以文字形式给出的定义说明 | 知识层次: 题目考查对完美位错这一基本概念的定义记忆，属于材料科学中晶体缺陷的基础知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别完美位错的基本定义（柏氏矢量是晶格矢量的整数倍）。这属于最基础的概念记忆题，不需要解释或分析过程，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The Burgers vector is an integer multiple of the lattice vector.", "choice_question": "Which of the following correctly describes a perfect dislocation?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Burgers vector is an integer multiple of the lattice vector", "B": "The dislocation line terminates at a grain boundary", "C": "The Burgers vector magnitude equals the atomic radius", "D": "The dislocation creates a stacking fault in FCC crystals" }, "correct_answer": "A", "explanation": "Correct answer A defines the fundamental characteristic of perfect dislocations in crystalline materials. Option B exploits the common misconception that dislocations must terminate at boundaries. Option C uses an intuitive but incorrect atomic-scale assumption. Option D creates confusion by mixing perfect dislocations with partial dislocations that do create stacking faults.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3710, "question": "A 850-lb force is applied to a 0.15-in. diameter nickel wire having a yield strength of 45,000 psi and a tensile strength of 55,000 psi. Determine whether the wire will experience necking.", "answer": "no necking will occur (48,100 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算（计算应力并与屈服强度和抗拉强度比较）来判断是否会发生颈缩现象，答案给出了具体的计算结果（48,100 psi）和结论。 | 知识层次: 题目需要进行简单的应力计算（力除以横截面积），并将计算结果与给定的材料强度参数进行比较。虽然涉及公式应用，但计算步骤单一，无需多步推理或综合分析，属于基本公式的直接套用和简单判断。 | 难度: 在选择题型中，该题目属于简单应用层次，需要应用基本公式（应力计算）并进行简单计算。虽然涉及应力与材料强度的比较，但解题步骤较为直接，仅需套用公式并比较数值，无需多个公式组合或复杂分析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "no necking will occur", "choice_question": "A 850-lb force is applied to a 0.15-in. diameter nickel wire having a yield strength of 45,000 psi and a tensile strength of 55,000 psi. What will happen to the wire?", "conversion_reason": "The answer is a specific and definitive statement ('no necking will occur'), which can be presented as one of the options in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the outcome.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The wire will undergo uniform plastic deformation without necking", "B": "The wire will fracture immediately due to stress concentration", "C": "The wire will experience significant necking followed by rupture", "D": "The wire will return to its original shape after elastic deformation" }, "correct_answer": "A", "explanation": { "correct_answer": "The calculated stress (48,100 psi) is between yield and tensile strength, causing plastic deformation but not reaching the necking threshold (tensile strength).", "distractor_strategies": { "B": "Exploits AI's tendency to overestimate stress concentration effects in small diameter wires.", "C": "Lures AI with the common necking-fracture narrative without checking actual stress values.", "D": "Targets AI's confusion between elastic limit (below yield) and plastic deformation range." } }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3763, "question": "Calculate the height of the cylindrical riser required to prevent shrinkage in a 1 in. x 6 in. x 6 in. casting if the H/D of the riser is 1.0.", "answer": "the height of the riser must be at least 2.25 in.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算圆柱形冒口的高度），并给出了具体的尺寸条件和比例要求（H/D=1.0），最终答案是一个具体的数值（2.25 in）。这符合计算题的特征，即需要应用公式和进行数值计算来解决问题。 | 知识层次: 题目涉及基本的公式应用和简单计算，需要根据给定的H/D比例和铸件尺寸计算冒口高度，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于简单应用层次，需要基本公式应用和简单计算。虽然涉及H/D比的概念，但解题步骤相对直接，只需套用给定比例进行计算即可。相比等级1的直接计算，此题需要理解H/D比的含义，因此属于等级2。", "convertible": true, "correct_option": "the height of the riser must be at least 2.25 in.", "choice_question": "What is the height of the cylindrical riser required to prevent shrinkage in a 1 in. x 6 in. x 6 in. casting if the H/D of the riser is 1.0?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.25 in", "B": "1.5 in", "C": "3.0 in", "D": "4.5 in" }, "correct_answer": "A", "explanation": "The correct answer is A (2.25 in) because the riser volume must be at least equal to the casting's shrinkage volume. For a 1 in x 6 in x 6 in casting, the riser diameter should be 2.25 in (based on Chvorinov's rule and modulus calculations), and with H/D=1.0, height is also 2.25 in. Option B (1.5 in) exploits the common mistake of using the thinnest casting dimension. Option C (3.0 in) traps those who incorrectly consider only the largest casting dimension. Option D (4.5 in) targets those who double the correct value due to misapplied safety factors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1805, "question": "What are grain growth and secondary recrystallization?", "answer": "Grain growth is the process in which the average grain size of a strain-free material continuously increases during heat treatment without altering its distribution. Within the body, grain sizes grow uniformly, and during grain growth, pores remain at grain boundaries or their intersections. Secondary recrystallization is an abnormal growth process where a few large grains grow at the expense of fine grains, representing the abnormal growth of individual grains. During secondary recrystallization, pores become trapped inside the grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"grain growth\"和\"secondary recrystallization\"这两个概念进行文字解释和论述，答案提供了详细的定义和特征描述，符合简答题的特点。 | 知识层次: 题目考查对晶粒生长和二次再结晶这两个基本概念的定义和特征的理解和记忆，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述的难度等级。题目要求考生理解和记忆晶粒生长和二次再结晶的定义及其基本特征，虽然涉及两个概念，但都是基础性的定义描述，不需要复杂的分析或比较。正确选项提供了清晰的定义和关键特征，符合选择题型中对概念解释和描述的要求。", "convertible": true, "correct_option": "Grain growth is the process in which the average grain size of a strain-free material continuously increases during heat treatment without altering its distribution. Within the body, grain sizes grow uniformly, and during grain growth, pores remain at grain boundaries or their intersections. Secondary recrystallization is an abnormal growth process where a few large grains grow at the expense of fine grains, representing the abnormal growth of individual grains. During secondary recrystallization, pores become trapped inside the grains.", "choice_question": "Which of the following correctly describes grain growth and secondary recrystallization?", "conversion_reason": "The answer is a standard definition that can be presented as one of the options in a multiple-choice question. The question can be rephrased to ask for the correct description among given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain growth is the uniform increase in grain size where pores remain at boundaries, while secondary recrystallization involves abnormal growth where pores get trapped inside grains", "B": "Both processes involve uniform grain size increase, but secondary recrystallization occurs at lower temperatures than primary grain growth", "C": "Grain growth eliminates all pores, while secondary recrystallization introduces new porosity at triple junctions", "D": "Secondary recrystallization is simply accelerated grain growth that occurs when heating rates exceed 50°C/min" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the key differences: uniform vs abnormal growth, and pore location dynamics. Option B exploits temperature misconception (both occur at high T). Option C reverses pore behavior (cognitive bias). Option D creates a false quantitative threshold (professional intuition trap). Advanced AIs might select B due to overgeneralization of temperature effects, or D due to pattern-matching with kinetic thresholds.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1088, "question": "Assuming carbon atoms are all located in the octahedral interstices of γ-Fe, at 1000°C, 1.7 weight percent of carbon atoms are dissolved in γ-Fe. Calculate how many carbon atoms are present in 100 unit cells and determine the proportion of octahedral interstices occupied by carbon atoms (the atomic weight of iron is 55.85, and the atomic weight of carbon is 12.01).", "answer": "γ-Fe has a face-centered cubic structure, with 4 Fe atoms and 4 octahedral interstices per unit cell. Let the number of carbon atoms in one unit cell be $A$, then: Solving gives $A=0.32$ $$\\frac{100A\\times12.01}{100\\times4\\times55.85+100A\\times12.01}=1.7\\%$$ Thus, the number of carbon atoms in 100 unit cells is: $0.32\\times100=32$ The proportion of octahedral interstices occupied by C atoms: $$A/4=0.32/4=0.08=8\\%$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，解答过程涉及单位换算、比例计算和百分比求解，最终需要得出具体的数值结果。 | 知识层次: 题目涉及多步计算和概念关联，需要理解γ-Fe的面心立方结构、八面体间隙的位置和数量，以及碳原子在其中的溶解比例。同时，需要进行质量百分比和原子数量的转换计算，综合分析碳原子占据间隙的比例。这超出了简单应用的范围，但尚未达到复杂分析或高级综合的层次。 | 难度: 在选择题中属于中等偏上难度，需要理解面心立方结构、间隙位置、原子百分比与重量百分比转换等多个概念，并进行多步骤的综合计算。虽然题目提供了正确选项作为参考，但仍需要考生具备较强的概念关联能力和计算能力才能正确解答。", "convertible": true, "correct_option": "32 carbon atoms and 8% of octahedral interstices occupied", "choice_question": "Assuming carbon atoms are all located in the octahedral interstices of γ-Fe, at 1000°C, 1.7 weight percent of carbon atoms are dissolved in γ-Fe. Calculate how many carbon atoms are present in 100 unit cells and determine the proportion of octahedral interstices occupied by carbon atoms (the atomic weight of iron is 55.85, and the atomic weight of carbon is 12.01).", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "32 carbon atoms and 8% of octahedral interstices occupied", "B": "16 carbon atoms and 4% of octahedral interstices occupied", "C": "64 carbon atoms and 16% of octahedral interstices occupied", "D": "8 carbon atoms and 2% of octahedral interstices occupied" }, "correct_answer": "A", "explanation": "The correct answer is A because: 1) γ-Fe has an FCC structure with 4 iron atoms per unit cell, so 100 unit cells contain 400 iron atoms. 2) At 1.7 wt% carbon, the atomic percentage is calculated as (1.7/12.01)/(1.7/12.01 + 98.3/55.85) ≈ 7.4 at%. 3) This corresponds to 32 carbon atoms in 100 unit cells (400×7.4%≈30, rounded to nearest whole number). 4) Each FCC unit cell has 4 octahedral interstices, so 100 unit cells have 400 interstices, giving 32/400=8% occupancy. Option B is a common half-value error from misinterpreting the unit cell count. Option C doubles the correct value, exploiting a common calculation error. Option D is a quarter-value error from incorrect weight-to-atom conversion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3726, "question": "Will the polymer fracture if its flexural strength is 85 MPa? Assume that no plastic deformation occurs.", "answer": "the applied stress is 61.5 MPa, which is less than the flexural strength of 85 MPa; the polymer is not expected to fracture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求通过比较施加应力和弯曲强度来判断聚合物是否会断裂，答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目涉及基本公式应用和简单计算，只需比较施加应力与弯曲强度的数值关系即可得出结论，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需比较施加应力（61.5 MPa）与弯曲强度（85 MPa）的数值关系即可得出结论。解题步骤直接，无需复杂计算或深入分析，符合等级2\"简单应用过程描述\"的标准。", "convertible": true, "correct_option": "No, the polymer is not expected to fracture.", "choice_question": "Will the polymer fracture if its flexural strength is 85 MPa and the applied stress is 61.5 MPa? Assume that no plastic deformation occurs.", "conversion_reason": "The answer provides a clear conclusion based on the given conditions, which can be directly converted into a correct option for a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, the polymer is not expected to fracture", "B": "Yes, because the applied stress exceeds 60% of the flexural strength", "C": "Yes, due to stress concentration effects at the molecular level", "D": "No, but permanent deformation will occur despite the assumption" }, "correct_answer": "A", "explanation": "The correct answer is A because the applied stress (61.5 MPa) is below the flexural strength (85 MPa) and the question specifies no plastic deformation occurs. Option B exploits the cognitive bias of percentage thresholds (60% seems significant but is irrelevant here). Option C uses a valid material science concept (stress concentration) but incorrectly applies it to this macroscopic scenario. Option D contradicts the given assumption about plastic deformation while appearing to be a cautious answer.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1334, "question": "Explain the reversibility of the first type of temper embrittlement", "answer": "The first type of temper embrittlement is irreversible temper embrittlement.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释第一类回火脆性的可逆性，需要文字解释和论述，答案提供了简要的论述而非选择或判断 | 知识层次: 题目考查对第一类回火脆性可逆性的基本概念记忆和理解，属于定义和分类的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆和识别基本定义（第一类回火脆性的不可逆性），属于最基础的概念记忆层次，无需复杂分析或推理步骤。", "convertible": true, "correct_option": "The first type of temper embrittlement is irreversible temper embrittlement.", "choice_question": "Which of the following describes the reversibility of the first type of temper embrittlement?", "conversion_reason": "The answer is a standard terminology or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The embrittlement can be reversed by rapid quenching from austenitizing temperature", "B": "The embrittlement is reversible through prolonged annealing at 600-650°C", "C": "The first type of temper embrittlement is irreversible temper embrittlement", "D": "Reversibility depends on the cooling rate through the 400-550°C range" }, "correct_answer": "C", "explanation": "The first type of temper embrittlement is indeed irreversible due to the segregation of impurity elements to grain boundaries. Option A is a cognitive bias trap, confusing it with quench embrittlement. Option B is a professional intuition trap, mimicking the behavior of second type temper embrittlement. Option D is a multi-level verification trap, combining correct temperature ranges with incorrect mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4027, "question": "Which of the following kinds of information may be determined with the aid of a phase diagram? The phase(s) present at a specified temperature and composition.", "answer": "With the aid of a phase diagram the following may be determined: The phase(s) present at a specified temperature and composition.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项中选择正确的信息类型，符合选择题的特征 | 知识层次: 题目考查对相图基本功能的理解和记忆，即通过相图确定特定温度和成分下的相组成，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念记忆类型，仅需识别相图的基本功能（确定特定温度和成分下的相态），无需复杂分析或概念辨析。在选择题型中属于最简单的直接记忆类题目。", "convertible": true, "correct_option": "The phase(s) present at a specified temperature and composition.", "choice_question": "Which of the following kinds of information may be determined with the aid of a phase diagram?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provided is a clear and concise option that can serve as the correct choice in a single-answer question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phase(s) present at a specified temperature and composition", "B": "The elastic modulus of a specific phase at room temperature", "C": "The diffusion coefficient of solute atoms in the matrix phase", "D": "The exact processing parameters for achieving desired microstructure" }, "correct_answer": "A", "explanation": "Phase diagrams only provide information about equilibrium phases present at given temperature and composition conditions (A). Option B is incorrect because mechanical properties like elastic modulus cannot be determined from phase diagrams. Option C is wrong as kinetic properties like diffusion coefficients require additional data. Option D is a trap as phase diagrams show equilibrium states but not processing paths. Advanced AI might incorrectly select B or C due to common confusion between thermodynamic and mechanical/kinetic properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1303, "question": "What is the structure of austenite?", "answer": "Austenite: An interstitial solid solution of carbon in γ-Fe, with a face-centered cubic structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释奥氏体的结构，答案提供了详细的文字描述，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对奥氏体结构的基本定义和晶体结构的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别奥氏体的基本定义和晶体结构（面心立方结构）。这属于最基础的概念记忆层次，不需要解释或分析多个概念，解题步骤非常简单直接。", "convertible": true, "correct_option": "An interstitial solid solution of carbon in γ-Fe, with a face-centered cubic structure", "choice_question": "Which of the following correctly describes the structure of austenite?", "conversion_reason": "The answer is a standard definition of austenite's structure, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An interstitial solid solution of carbon in γ-Fe, with a face-centered cubic structure", "B": "A substitutional solid solution of carbon in α-Fe, with a body-centered cubic structure", "C": "An interstitial solid solution of carbon in δ-Fe, with a body-centered cubic structure", "D": "A substitutional solid solution of carbon in γ-Fe, with a face-centered cubic structure" }, "correct_answer": "A", "explanation": "The correct answer is A because austenite is indeed an interstitial solid solution of carbon in γ-Fe (gamma iron) with a face-centered cubic (FCC) structure. Option B is incorrect because it describes ferrite (α-Fe with BCC structure), not austenite, exploiting the common confusion between these two phases. Option C is wrong by mixing the high-temperature δ-Fe (which has BCC structure) with the concept of austenite, creating a plausible but non-existent phase. Option D is particularly deceptive as it maintains the correct crystal structure (FCC) but incorrectly describes the solution type as substitutional, which is a subtle but critical distinction in phase identification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3629, "question": "For \\mathrm{UO}_{2} with fluorite structure, determine the lattice parameter.", "answer": "5.2885 Å.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求确定UO2的晶格参数，需要通过计算或查阅相关数据得出具体数值（5.2885 Å），属于需要数值结果的计算题。 | 知识层次: 题目要求确定UO2的晶格参数，这属于基本公式应用和简单计算，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求确定具有萤石结构的UO₂的晶格参数，正确选项直接给出数值5.2885 Å。解题过程仅需应用基本公式或直接引用已知数据，无需复杂计算或多步骤推理。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "5.2885 Å", "choice_question": "For \\mathrm{UO}_{2} with fluorite structure, the lattice parameter is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.2885 Å", "B": "5.470 Å (CaF₂ lattice parameter)", "C": "5.128 Å (hypothetical UO₂ with NaCl structure)", "D": "5.420 Å (ZrO₂ lattice parameter)" }, "correct_answer": "A", "explanation": "The correct lattice parameter for UO₂ with fluorite structure is 5.2885 Å (A). Option B uses the lattice parameter of CaF₂ (another fluorite structure material) to exploit material analogy fallacy. Option C creates a hypothetical scenario with wrong crystal structure to trigger structural confusion. Option D introduces a chemically similar oxide (ZrO₂) with close but incorrect value to exploit unit cell size estimation bias.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2700, "question": "Given the vibration frequency of atoms around a vacancy in Cu as 1×10¹³ s⁻¹, ΔEv as 0.15×10⁻¹⁸ J, and exp(ΔSm/k) approximately 1, calculate the migration frequency of vacancies at room temperature 27°C (300K).", "answer": "ν=ν₀zexp(−ΔEv/kT)exp(ΔSm/k), ν₃₀₀=1×10¹³×12×exp(−0.15×10⁻¹⁸/(1.38×10⁻²³×300))×1=2.207×10⁻² s⁻¹", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，给出了具体的物理参数和计算公式，最终需要计算出迁移频率的数值结果。答案也是一个具体的数值计算结果，符合计算题的特征。 | 知识层次: 题目需要应用公式进行多步计算，涉及振动频率、迁移能、熵变等多个概念的关联，并需要正确代入数值进行计算，思维过程有一定深度要求。 | 难度: 在选择题中属于中等偏上难度，需要理解振动频率、迁移能、熵变等多个概念，并正确应用Arrhenius方程进行多步骤计算。题目涉及单位换算（温度转换）、指数运算和常数代入，计算过程较为复杂，但选项提供了完整的解题路径，降低了部分难度。", "convertible": true, "correct_option": "2.207×10⁻² s⁻¹", "choice_question": "Given the vibration frequency of atoms around a vacancy in Cu as 1×10¹³ s⁻¹, ΔEv as 0.15×10⁻¹⁸ J, and exp(ΔSm/k) approximately 1, what is the migration frequency of vacancies at room temperature 27°C (300K)?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as the correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.207×10⁻² s⁻¹", "B": "1.104×10¹³ s⁻¹", "C": "4.414×10⁻² s⁻¹", "D": "1.104×10⁻² s⁻¹" }, "correct_answer": "A", "explanation": "正确答案A是通过Arrhenius方程正确计算得出的迁移频率：ν = ν₀exp(-ΔEv/kT) = 1×10¹³ × exp(-0.15×10⁻¹⁸/(1.38×10⁻²³×300)) ≈ 2.207×10⁻² s⁻¹。干扰项B直接使用了振动频率ν₀，忽略了指数衰减项；干扰项C是正确答案的两倍，利用了数值接近但单位不同的陷阱；干扰项D是正确答案的一半，利用了常见的系数错误直觉。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 171, "question": "When Na2O is added to SiO2, making O/Si=2.5, is the crystallization ability enhanced or weakened?", "answer": "Because O/Si increases, the viscosity decreases, and the crystallization ability is enhanced.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释Na2O添加到SiO2中导致O/Si=2.5时结晶能力的变化，答案提供了文字解释和论述，说明粘度降低和结晶能力增强的原因，符合简答题的特征。 | 知识层次: 题目需要理解Na2O和SiO2的相互作用对O/Si比的影响，以及O/Si比变化对粘度和结晶能力的影响。这涉及到多个概念的关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及Na2O和SiO2的反应，以及O/Si比例变化对粘度和结晶能力的影响。虽然题目给出了正确选项，但学生需要掌握相关概念（如O/Si比例、粘度与结晶能力的关系）才能正确选择。这需要一定的综合分析能力，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "Because O/Si increases, the viscosity decreases, and the crystallization ability is enhanced.", "choice_question": "When Na2O is added to SiO2, making O/Si=2.5, what happens to the crystallization ability?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystallization ability is enhanced due to decreased viscosity from increased O/Si ratio", "B": "Crystallization ability is weakened because Na+ ions disrupt the silicate network", "C": "Crystallization ability remains unchanged as the system reaches a metastable state", "D": "Crystallization ability first increases then decreases due to competing network modifiers" }, "correct_answer": "A", "explanation": "The correct answer is A because increasing O/Si ratio reduces network connectivity, lowering viscosity and enhancing crystallization. Option B exploits the common misconception that network modifiers always weaken crystallization. Option C targets AI's tendency to predict metastable states. Option D creates a complex scenario that seems plausible but doesn't apply at O/Si=2.5.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 672, "question": "Explain the basic concept of dislocations", "answer": "Dislocations are a type of arrangement defect in crystal structures, which can be divided into edge dislocations, screw dislocations, and mixed dislocations.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释位错的基本概念，答案提供了文字解释和论述，符合简答题的特征 | 知识层次: 题目要求解释位错的基本概念和分类，属于对晶体缺陷基础知识的记忆和理解，不涉及应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别位错的基本定义和分类，属于最基础的概念性知识。题目正确选项直接给出了定义和分类，无需进行复杂的概念比较或分析，因此属于难度等级1。", "convertible": true, "correct_option": "Dislocations are a type of arrangement defect in crystal structures, which can be divided into edge dislocations, screw dislocations, and mixed dislocations.", "choice_question": "Which of the following best describes the basic concept of dislocations?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dislocations are a type of arrangement defect in crystal structures, which can be divided into edge dislocations, screw dislocations, and mixed dislocations.", "B": "Dislocations are temporary distortions in atomic spacing that fully recover upon removal of applied stress, similar to elastic deformation.", "C": "Dislocations refer to the complete breakage of atomic bonds leading to permanent material failure, analogous to brittle fracture.", "D": "Dislocations are equilibrium defects that minimize system energy by creating perfect crystalline regions separated by disordered boundaries." }, "correct_answer": "A", "explanation": "Option A is correct as it accurately describes dislocations as crystallographic defects that enable plastic deformation through their movement. Option B exploits confusion between elastic deformation (temporary) and plastic deformation (permanent via dislocation motion). Option C triggers incorrect association with fracture mechanics rather than deformation mechanisms. Option D mimics grain boundary descriptions while ignoring dislocation's non-equilibrium nature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4540, "question": "Contrast the mechanical characteristics of matrix and dispersed phases for fiber-reinforced composites.", "answer": "In general, the matrix phase is relatively weak, has a low elastic modulus, but is quite ductile. On the other hand, the fiber phase is normally quite strong, stiff, and brittle.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对比纤维增强复合材料中基体和分散相的力学特性，需要文字解释和论述，而不是选择、判断或计算。答案也提供了详细的文字描述，符合简答题的特征。 | 知识层次: 题目考查对纤维增强复合材料中基体和分散相机械特性的基本概念记忆和理解，无需复杂分析或综合应用。 | 难度: 在选择题型中，该题目要求考生对比纤维增强复合材料中基体和分散相的机械特性。虽然涉及两个相的特性描述，但知识点较为基础，属于概念解释和描述的层次。解题步骤相对简单，只需记忆并区分基体和纤维相的基本特性即可，无需复杂的分析或推导。因此，在选择题型内属于中等偏下的难度。", "convertible": true, "correct_option": "In general, the matrix phase is relatively weak, has a low elastic modulus, but is quite ductile. On the other hand, the fiber phase is normally quite strong, stiff, and brittle.", "choice_question": "Which of the following correctly contrasts the mechanical characteristics of matrix and dispersed phases for fiber-reinforced composites?", "conversion_reason": "The answer is a standard description of the mechanical characteristics of matrix and dispersed phases, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The matrix phase exhibits high toughness but low yield strength, while fibers show high tensile strength but poor creep resistance", "B": "Matrix materials typically have higher fracture toughness than fibers, but fibers compensate with superior fatigue resistance", "C": "While the matrix provides most of the composite's stiffness, fibers contribute primarily to impact resistance", "D": "The matrix phase dominates thermal conductivity properties, whereas fibers control the electrical conductivity" }, "correct_answer": "A", "explanation": "Correct answer A accurately describes the fundamental mechanical contrast: matrices provide toughness (energy absorption) but lower strength, while fibers provide high tensile strength but are brittle. Option B incorrectly suggests fibers have superior fatigue resistance (actually matrix-dependent). Option C inverts the stiffness contribution (fibers provide stiffness). Option D introduces irrelevant properties (thermal/electrical conductivity) not asked about in mechanical characteristics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 454, "question": "What is a smooth interface?", "answer": "Smooth interface: It is another type of solid-liquid interface where the atoms on the solid-phase interface are arranged into a flat atomic plane, specifically a certain crystallographic plane.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对“smooth interface”进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对平滑界面这一基本概念的定义和特征的理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆和识别“smooth interface”的基本定义，属于基础概念记忆层次。正确选项直接给出了定义，没有涉及复杂的概念体系或需要推理分析的内容，因此属于最简单的难度等级。", "convertible": true, "correct_option": "It is another type of solid-liquid interface where the atoms on the solid-phase interface are arranged into a flat atomic plane, specifically a certain crystallographic plane.", "choice_question": "Which of the following best describes a smooth interface?", "conversion_reason": "The answer is a standard definition of a smooth interface, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It is another type of solid-liquid interface where the atoms on the solid-phase interface are arranged into a flat atomic plane, specifically a certain crystallographic plane.", "B": "A liquid-solid interface with complete atomic disorder and no preferred crystallographic orientation.", "C": "An interface between two amorphous phases where atomic positions are completely randomized.", "D": "A solid-solid interface where both phases maintain their crystal structure but with significant lattice mismatch." }, "correct_answer": "A", "explanation": "The correct answer is A because a smooth interface specifically refers to a solid-liquid interface with a well-defined crystallographic plane. Option B is incorrect as it describes a rough interface. Option C is a trap for those confusing smooth interfaces with amorphous-amorphous interfaces. Option D exploits the common misconception that smooth interfaces can occur between crystalline solids with lattice mismatch.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1273, "question": "The typical crystal structure types of metals are fcc, bcc, and hcp, with coordination numbers of (1), (2), and (3) respectively.", "answer": "(1) 12; (2) 8; (3) 12", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的数值作为答案，而不是从给定的选项中选择或判断对错。虽然答案简短，但需要基于对晶体结构类型的理解来回答，属于简答题的范畴。 | 知识层次: 题目考查金属典型晶体结构类型及其配位数的记忆，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆金属晶体结构的配位数即可作答。题目提供了明确的结构类型（fcc、bcc、hcp）与对应配位数的匹配关系，无需额外推理或分析步骤，符合等级1\"基本定义简答\"的难度标准。", "convertible": true, "correct_option": "(1) 12; (2) 8; (3) 12", "choice_question": "The typical crystal structure types of metals are fcc, bcc, and hcp, with coordination numbers of (1), (2), and (3) respectively. Which of the following is correct?", "conversion_reason": "The answer is a standard set of terms (coordination numbers) that can be presented as options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(1) 12; (2) 8; (3) 12", "B": "(1) 12; (2) 12; (3) 12", "C": "(1) 8; (2) 8; (3) 12", "D": "(1) 12; (2) 8; (3) 8" }, "correct_answer": "A", "explanation": "The correct coordination numbers are 12 for fcc (face-centered cubic), 8 for bcc (body-centered cubic), and 12 for hcp (hexagonal close-packed). Option B incorrectly assigns 12 to bcc, exploiting the common misconception that all close-packed structures have the same coordination number. Option C wrongly gives 8 to fcc, playing on the confusion between fcc and bcc structures. Option D incorrectly assigns 8 to hcp, capitalizing on the rare but possible confusion between hcp and bcc coordination numbers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4233, "question": "What is the composition, in atom percent, of an alloy that contains 99.7 lb_{m} copper, 102 lb_{m} zinc, and 2.1 lb_{m} lead?\n", "answer": "the composition of the alloy in atom percent is: \\[\nc_{\\mathrm{cu}} = 50.0 \\, \\text{at}%\n\\] \\[\nc_{\\mathrm{zn}} = 49.7 \\, \\text{at}%\n\\] \\[\nc_{\\mathrm{pb}} = 0.3 \\, \\text{at}%\n\\]", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求计算合金中各元素的原子百分比，需要通过数值计算和公式应用来得出具体数值。答案以具体的数值形式给出，符合计算题的特征。 | 知识层次: 题目需要进行基本的数值计算和公式应用，涉及原子百分比的转换，但计算过程相对直接，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，需要应用基本的原子百分比计算公式，并进行简单的数值计算。虽然涉及多个元素的质量转换和百分比计算，但步骤较为直接，属于简单公式应用计算。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "c_{\\mathrm{cu}} = 50.0 \\, \\text{at}%, c_{\\mathrm{zn}} = 49.7 \\, \\text{at}%, c_{\\mathrm{pb}} = 0.3 \\, \\text{at}%", "choice_question": "What is the composition, in atom percent, of an alloy that contains 99.7 lb_{m} copper, 102 lb_{m} zinc, and 2.1 lb_{m} lead?", "conversion_reason": "The question is a calculation problem with a specific and deterministic answer, making it suitable for conversion to a multiple-choice format. The correct option can be directly derived from the provided answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "c_{\\mathrm{cu}} = 50.0 \\, \\text{at}%, c_{\\mathrm{zn}} = 49.7 \\, \\text{at}%, c_{\\mathrm{pb}} = 0.3 \\, \\text{at}%", "B": "c_{\\mathrm{cu}} = 49.7 \\, \\text{at}%, c_{\\mathrm{zn}} = 50.0 \\, \\text{at}%, c_{\\mathrm{pb}} = 0.3 \\, \\text{at}%", "C": "c_{\\mathrm{cu}} = 49.7 \\, \\text{wt}%, c_{\\mathrm{zn}} = 50.0 \\, \\text{wt}%, c_{\\mathrm{pb}} = 0.3 \\, \\text{wt}%", "D": "c_{\\mathrm{cu}} = 50.0 \\, \\text{wt}%, c_{\\mathrm{zn}} = 49.7 \\, \\text{wt}%, c_{\\mathrm{pb}} = 0.3 \\, \\text{wt}%" }, "correct_answer": "A", "explanation": "The correct answer requires precise calculation of atomic percentages considering the atomic weights of Cu (63.55 g/mol), Zn (65.38 g/mol), and Pb (207.2 g/mol). Option B reverses the Cu and Zn percentages, exploiting the similar atomic weights of these elements. Option C uses weight percentages instead of atomic percentages, a common unit confusion. Option D provides correct weight percentages but the question asks for atomic percentages.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1947, "question": "What is equilibrium crystallization?", "answer": "Equilibrium crystallization refers to crystallization that occurs at a very slow rate, with sufficient diffusion in both the liquid and solid phases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"equilibrium crystallization\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即equilibrium crystallization的定义和基本原理，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆，但需要考生理解并描述\"equilibrium crystallization\"的定义和特点，而不仅仅是简单的名词解释。正确选项提供了较为详细的解释，涉及结晶速率和扩散过程，这比单纯记忆定义要复杂一些，属于概念解释和描述的层次。", "convertible": true, "correct_option": "Equilibrium crystallization refers to crystallization that occurs at a very slow rate, with sufficient diffusion in both the liquid and solid phases.", "choice_question": "Which of the following best describes equilibrium crystallization?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct definition as one of the options and other plausible but incorrect definitions as distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Equilibrium crystallization refers to crystallization that occurs at a very slow rate, with sufficient diffusion in both the liquid and solid phases", "B": "Equilibrium crystallization is a rapid solidification process that prevents solute partitioning", "C": "Equilibrium crystallization occurs when the cooling rate matches the material's thermal conductivity", "D": "Equilibrium crystallization describes the point where nucleation rate equals grain growth rate" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines equilibrium crystallization as a slow process allowing complete diffusion. Option B is a cognitive bias trap, confusing equilibrium with non-equilibrium rapid solidification. Option C exploits professional intuition by mixing thermal concepts incorrectly. Option D creates a multi-level verification trap by combining two real but unrelated crystallization phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1871, "question": "Kaolinite belongs to the silicate of . A. Chain structure B. Layered structure C. Framework structure D. Island structure", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对高岭石（Kaolinite）所属硅酸盐结构类型的基础概念记忆，属于定义和分类的记忆性知识。 | 难度: 在选择题型中，此题属于简单概念识别，直接记忆类型。题目直接考察高岭石属于哪种硅酸盐结构，只需记住高岭石属于层状结构即可作答，无需进行概念辨析或复杂分析。", "convertible": true, "correct_option": "B", "choice_question": "Kaolinite belongs to the silicate of .", "conversion_reason": "The original question is already in a single-choice format with a clear correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship predicts increased yield strength with decreasing grain size in nanocrystalline materials (d < 10nm)", "B": "The inverse Hall-Petch effect occurs due to grain boundary sliding dominating deformation in ultrafine-grained materials", "C": "Grain boundary strengthening follows a d^(-1/2) relationship where d is the average grain diameter", "D": "The critical grain size for transition to inverse Hall-Petch behavior is material-independent" }, "correct_answer": "C", "explanation": "Correct answer C is the classical Hall-Petch relationship. Distractors employ: A) Misapplies Hall-Petch to nanocrystalline regime where it breaks down; B) Confuses mechanisms (sliding vs dislocation nucleation) and size range; D) Uses absolute statement about material independence when critical size varies by crystal structure and bonding.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1574, "question": "5. Austenite", "answer": "An interstitial solid solution of carbon dissolved in γ-Fe.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Austenite\"进行解释，答案是一个文字描述的定义，符合简答题的特征 | 知识层次: 题目考查对奥氏体（Austenite）这一基本概念的定义记忆，属于材料科学中基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，此题仅考察对奥氏体基本定义的记忆，属于最基础的概念性知识。正确选项直接给出了标准定义，不需要任何解释或分析步骤，完全符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "An interstitial solid solution of carbon dissolved in γ-Fe.", "choice_question": "下列关于Austenite的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An interstitial solid solution of carbon dissolved in γ-Fe", "B": "A substitutional solid solution of carbon in α-Fe with FCC structure", "C": "A metastable phase formed by rapid quenching of γ-Fe with BCC structure", "D": "A supersaturated solid solution of carbon in δ-Fe with HCP structure" }, "correct_answer": "A", "explanation": { "correct_answer": "Austenite is correctly defined as an interstitial solid solution of carbon in γ-Fe (FCC structure), which is the high-temperature stable phase of iron.", "distractors": { "B": "This option combines two common misconceptions: 1) confusing interstitial vs substitutional solutions (carbon always forms interstitial solutions in Fe), and 2) incorrectly assigning FCC structure to α-Fe (which is BCC).", "C": "This describes martensite formation, not austenite, playing on the common confusion between these two important phases in steel.", "D": "This option exploits three errors: 1) δ-Fe is BCC not HCP, 2) austenite is stable not supersaturated, and 3) uses the less common δ-Fe phase to create confusion with γ-Fe." }, "cognitive_traps": { "phase_structure_confusion": "Leverages the common difficulty in remembering which crystal structure (FCC/BCC/HCP) corresponds to which Fe phase (α/γ/δ).", "solution_type_trap": "Exploits the subtle distinction between interstitial and substitutional solid solutions that AI models often overlook.", "stability_misconception": "Uses the concept of metastability which is associated with martensite but not austenite." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4780, "question": "What is the driving force for recrystallization?", "answer": "The driving force for recrystallization is the difference in internal energy between the strained and unstrained material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述驱动力的概念，答案提供了详细的解释而非选择或判断 | 知识层次: 题目考查对再结晶驱动力的基本概念的理解和记忆，属于材料科学中的基本原理范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"再结晶驱动力\"的基本定义，属于最基础的概念性知识。正确选项直接给出了教科书式的定义表述，无需任何解释、分析或比较过程，完全符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "The difference in internal energy between the strained and unstrained material", "choice_question": "What is the driving force for recrystallization?", "conversion_reason": "The answer is a standard concept or term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The difference in internal energy between the strained and unstrained material", "B": "The reduction in dislocation density during annealing", "C": "The stored elastic strain energy in the crystal lattice", "D": "The thermodynamic instability of deformed grain boundaries" }, "correct_answer": "A", "explanation": { "correct_answer": "The difference in internal energy between the strained and unstrained material is the fundamental driving force for recrystallization, as it represents the system's tendency to minimize free energy.", "distractors": { "B": "This is a cognitive bias trap - while dislocation reduction occurs during recrystallization, it's a consequence rather than the driving force.", "C": "This is a professional intuition trap - elastic strain energy contributes but doesn't fully account for all internal energy changes.", "D": "This is a multi-level verification trap - while grain boundaries are important, the driving force originates from bulk material energy differences." } }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2947, "question": "The dislocation that can undergo cross-slip must be (A) edge dislocation (B) screw dislocation (C) mixed dislocation", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（A、B、C）中选择关于位错类型的正确答案 | 知识层次: 题目考查对位错类型及其特性的基本概念记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆层次，要求考生理解并区分不同类型的位错（刃型位错、螺型位错、混合位错）的基本特性。虽然题目直接考察的是记忆性知识，但需要考生对位错类型及其行为（如交滑移）有明确的理解和简单辨析能力，因此属于中等难度。", "convertible": true, "correct_option": "B", "choice_question": "The dislocation that can undergo cross-slip must be", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "edge dislocation", "B": "screw dislocation", "C": "mixed dislocation", "D": "all dislocation types can cross-slip" }, "correct_answer": "B", "explanation": "Cross-slip requires dislocations with pure screw character because only screw dislocations can change slip planes while maintaining their Burgers vector. Edge dislocations (A) cannot cross-slip due to their fixed slip plane. Mixed dislocations (C) can only cross-slip in their screw components. Option D is a common oversimplification trap that ignores fundamental dislocation mechanics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2600, "question": "Estimate the equilibrium width of an extended dislocation in Al. Given the lattice constant of Al a = 0.404 nm, shear modulus G = 3×10^6 N/cm^2, and stacking fault energy γ_I = 166×10^-6 J/m^2.", "answer": "Al has a face-centered cubic structure, and the equilibrium width of an extended dislocation d_0 = G a^2 / (24πγ_I). Substituting the data: d_0 = (3×10^6 N/cm^2) × (0.404×10^-9 m)^2 / (24π × 166×10^-6 J/m^2) = 3.91×10^-7 m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的物理参数和公式进行数值计算，最终得出一个具体的数值结果。解答过程涉及公式应用和单位转换，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，无需多步推理或综合分析，仅需将给定数据代入公式进行计算即可。 | 难度: 在选择题中属于简单难度，仅需直接套用给定公式并进行简单计算，无需多个公式组合或复杂分析。", "convertible": true, "correct_option": "3.91×10^-7 m", "choice_question": "Estimate the equilibrium width of an extended dislocation in Al. Given the lattice constant of Al a = 0.404 nm, shear modulus G = 3×10^6 N/cm^2, and stacking fault energy γ_I = 166×10^-6 J/m^2. The equilibrium width is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.91×10^-7 m", "B": "1.23×10^-7 m", "C": "7.82×10^-7 m", "D": "2.45×10^-7 m" }, "correct_answer": "A", "explanation": "正确答案A是通过Peierls-Nabarro模型计算得到的平衡宽度，考虑了剪切模量和堆垛层错能的精确关系。干扰项B错误地使用了弹性模量而非剪切模量进行计算。干扰项C是正确答案的两倍，源于错误地考虑了双位错扩展。干扰项D则是基于错误的假设，即堆垛层错能与晶格常数直接成反比关系。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 903, "question": "Term explanation: secondary recrystallization", "answer": "The phenomenon of abnormal growth of a few grains occurring when normal growth is inhibited after the completion of recrystallization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对术语进行解释，需要文字解释和论述，答案形式为一段文字描述，符合简答题的特征 | 知识层次: 题目考查对\"二次再结晶\"这一基本概念的定义记忆和理解，属于材料科学中基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。虽然题目要求解释\"secondary recrystallization\"这一专业术语，但正确选项提供了明确的定义描述，不需要进行复杂的概念体系阐述或比较分析。学生只需理解并记忆该现象的基本定义即可作答，不需要深入理解其机理或与其他概念的关联。因此，在选择题型内属于中等偏下的难度水平。", "convertible": true, "correct_option": "The phenomenon of abnormal growth of a few grains occurring when normal growth is inhibited after the completion of recrystallization.", "choice_question": "Which of the following best defines secondary recrystallization?", "conversion_reason": "The answer is a standard definition of a term, which can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phenomenon of abnormal growth of a few grains occurring when normal growth is inhibited after the completion of recrystallization", "B": "A second stage of recrystallization that occurs at higher temperatures than primary recrystallization", "C": "The process where previously recrystallized grains undergo further refinement through additional heat treatment", "D": "The simultaneous occurrence of recrystallization and grain growth during thermal processing" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines secondary recrystallization as the abnormal growth phenomenon after normal recrystallization is inhibited. Option B is a temperature-based misconception that exploits the 'secondary=higher temperature' cognitive bias. Option C describes grain refinement rather than abnormal growth, playing on the 'secondary=additional processing' intuition. Option D combines two distinct phenomena, exploiting the common confusion between recrystallization and grain growth processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1419, "question": "The bonding type of a material determines the level of its elastic modulus. What type of bond predominates in oxide ceramic materials, how strong is the bonding, and thus how is their elastic modulus?", "answer": "Oxide ceramic materials are predominantly ionic bonded, with strong bonding, hence their elastic modulus is relatively high.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目需要解释和论述氧化物陶瓷材料的主要键合类型、键合强度及其对弹性模量的影响，答案以文字形式给出，没有选项或计算要求。 | 知识层次: 题目考查对氧化物陶瓷材料中主要键合类型及其对弹性模量影响的基本概念记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆（材料键合类型和弹性模量的关系），但需要考生理解并关联多个知识点：氧化物陶瓷的主要键合类型、键合强度与弹性模量的关系。这超出了单纯的定义记忆（等级1），但尚未达到需要阐述复杂概念体系的难度（等级3）。", "convertible": true, "correct_option": "Oxide ceramic materials are predominantly ionic bonded, with strong bonding, hence their elastic modulus is relatively high.", "choice_question": "What type of bond predominates in oxide ceramic materials, how strong is the bonding, and thus how is their elastic modulus?", "conversion_reason": "The answer is a standard description that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Predominantly covalent bonding with moderate strength, resulting in intermediate elastic modulus", "B": "Mixed ionic-covalent bonding with variable strength, leading to a wide range of elastic moduli", "C": "Predominantly ionic bonding with strong bonding, hence high elastic modulus", "D": "Metallic bonding characteristics with delocalized electrons, producing low elastic modulus" }, "correct_answer": "C", "explanation": "The correct answer is C because oxide ceramics are indeed predominantly ionic bonded with strong electrostatic forces, which directly correlates with their high elastic modulus. Option A is a cognitive bias trap, exploiting the common misconception that ceramics must have covalent bonding. Option B uses partial truth (some ionic-covalent character) but exaggerates the variability. Option D is a professional intuition trap, playing on the metallic appearance of some oxides while ignoring their actual bonding nature.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1003, "question": "Assuming that the active slip system in a face-centered cubic crystal is (111)[011], please provide the Burgers vector of the unit dislocation for the slip.", "answer": "The Burgers vector of the unit dislocation is ${\\vec{b}}={\\frac{a}{2}}$ [011]", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求提供Burgers vector的具体表达式，需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目需要理解面心立方晶体中的滑移系统概念，并应用Burgers向量的计算方法。虽然涉及基础概念，但需要将多个知识点（滑移系统、Burgers向量计算）关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行综合分析。题目要求考生掌握面心立方晶体中的滑移系统（111）[011]，并正确识别单位位错的伯格斯矢量。这需要考生具备晶体结构、滑移系统和位错的基本知识，并能将这些概念关联起来进行多步计算。虽然题目给出了正确选项，但考生仍需理解伯格斯矢量的计算方法和单位位错的概念，才能确认选项的正确性。因此，在选择题型内，该题目属于中等应用难度，对应等级3。", "convertible": true, "correct_option": "${\\vec{b}}={\\frac{a}{2}}$ [011]", "choice_question": "Assuming that the active slip system in a face-centered cubic crystal is (111)[011], what is the Burgers vector of the unit dislocation for the slip?", "conversion_reason": "The answer is a standard and specific term, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "${\\vec{b}}={\\frac{a}{2}}$ [011]", "B": "${\\vec{b}}={\\frac{a}{2}}$ [101]", "C": "${\\vec{b}}=a$ [011]", "D": "${\\vec{b}}={\\frac{a}{\\sqrt{2}}}$ [011]" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC crystals, the Burgers vector of a unit dislocation is always ${\\frac{a}{2}}$<110>. For the given slip system (111)[011], the Burgers vector must be parallel to the slip direction [011]. Option B is incorrect because [101] is not the specified slip direction. Option C is a common mistake where the magnitude is incorrectly doubled. Option D uses the correct direction but introduces an incorrect magnitude factor of ${\\frac{1}{\\sqrt{2}}}$, which might seem plausible for normalized vectors but is wrong for Burgers vectors in this context.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4748, "question": "Consider a cylindrical specimen of some hypothetical metal alloy that has a diameter of 10.0 mm(0.39 in.). A tensile force of 1500N(340 lb) produces an elastic reduction in diameter of 6.7 × 10^{-4} mm(2.64 ×\n10^{-5} in.). Compute the elastic modulus of this alloy, given that Poisson's ratio is 0.35 .", "answer": "100 gpa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（如弹性模量的计算）来求解，答案是一个具体的数值（100 GPa），而不是选择、判断或文字解释。 | 知识层次: 题目需要进行多步计算，包括应用弹性模量、泊松比和应变之间的关系，涉及概念关联和综合分析。虽然计算过程较为直接，但需要理解和应用多个材料科学的基本原理，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要综合运用弹性模量、泊松比和应变计算等多个概念，并进行多步骤计算。虽然题目提供了所有必要参数，但解题过程涉及多个公式转换和单位换算，对学生的概念理解和计算能力要求较高。", "convertible": true, "correct_option": "100 GPa", "choice_question": "Consider a cylindrical specimen of some hypothetical metal alloy that has a diameter of 10.0 mm(0.39 in.). A tensile force of 1500N(340 lb) produces an elastic reduction in diameter of 6.7 × 10^{-4} mm(2.64 × 10^{-5} in.). Compute the elastic modulus of this alloy, given that Poisson's ratio is 0.35. The elastic modulus is:", "conversion_reason": "The question is a calculation problem with a definite numerical answer (100 GPa), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "100 GPa", "B": "70 GPa (using shear modulus formula with Poisson's ratio)", "C": "210 GPa (assuming steel-like behavior without calculation)", "D": "150 GPa (incorrectly using diameter change as strain)" }, "correct_answer": "A", "explanation": "The correct answer is A (100 GPa) calculated through proper stress-strain analysis. Option B exploits confusion between elastic and shear modulus formulas. Option C preys on the tendency to assume steel properties without calculation. Option D incorrectly uses diameter change directly as strain, bypassing Poisson's ratio considerations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1570, "question": "Briefly describe the recrystallization process of deformed metal during heating and the changes in its microstructure and properties", "answer": "After reaching or exceeding the recrystallization temperature, new grains with low defect density will form within the original deformed grains, and the grains are basically equiaxed. At this time, mechanical properties such as strength and physical properties quickly recover to the levels before deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述变形金属在加热过程中的再结晶过程及其微观结构和性能的变化，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目考查对金属再结晶过程的基本概念和原理的记忆和理解，包括再结晶温度、新晶粒的形成、微观结构和性能的变化等基础知识点。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及金属再结晶过程的基本概念和微观结构变化，但正确选项已经提供了较为详细的描述，包括再结晶温度、新晶粒的形成、缺陷密度降低以及力学性能恢复等关键点。这要求考生不仅记住基本定义，还需要理解并描述这些概念之间的关系和变化过程。然而，由于选项已经概括了主要知识点，不需要考生进行复杂的分析或比较，因此难度等级为2。", "convertible": true, "correct_option": "After reaching or exceeding the recrystallization temperature, new grains with low defect density will form within the original deformed grains, and the grains are basically equiaxed. At this time, mechanical properties such as strength and physical properties quickly recover to the levels before deformation.", "choice_question": "Which of the following best describes the recrystallization process of deformed metal during heating and the changes in its microstructure and properties?", "conversion_reason": "The answer is a standard description of the recrystallization process, which can be presented as one of several options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "After reaching or exceeding the recrystallization temperature, new grains with low defect density will form within the original deformed grains, and the grains are basically equiaxed. At this time, mechanical properties such as strength and physical properties quickly recover to the levels before deformation.", "B": "During heating, dislocations gradually annihilate through climb and cross-slip mechanisms, leading to a continuous decrease in strength and increase in ductility until reaching the pre-deformation state.", "C": "New equiaxed grains nucleate at grain boundaries first, then grow into the deformed matrix while maintaining the original crystallographic orientation, resulting in a texture-strengthened material.", "D": "Recovery occurs first as temperature increases, followed by recrystallization where subgrains rotate and coalesce to form new grains with identical orientation to the parent grain." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the recrystallization process where new defect-free grains form at sufficient temperature, leading to property recovery. Option B incorrectly describes a gradual process (characteristic of recovery) rather than the abrupt microstructural change of recrystallization. Option C contains the subtle trap of texture strengthening (wrong - recrystallization typically reduces texture) and orientation preservation (wrong - new grains have random orientations). Option D mixes truth (recovery first) with the false mechanism of subgrain rotation (characteristic of grain growth, not recrystallization nucleation).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4747, "question": "A cylindrical specimen of a metal alloy 10 mm(0.4 in.) in diameter is stressed elastically in tension. A force of 15,000N(3,370 lb r) produces a reduction in specimen diameter of 7 × 10^{-3} mm(2.8 × 10^{-4} in.). Compute Poisson's ratio for this material if its elastic modulus is 100 \\mathrm{GPa} \\left(14.5 × 10^{6} psi\\right).", "answer": "poisson's ratio for the material is v = 0.367 .", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解泊松比，需要运用弹性力学相关公式进行计算，最终给出一个具体的数值结果。 | 知识层次: 题目需要应用弹性模量和泊松比的定义，进行多步计算，包括应力、应变的计算以及泊松比的推导。虽然不涉及复杂的综合分析或创新应用，但需要理解相关概念并进行关联计算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。该题目涉及弹性模量、泊松比的计算，需要综合运用力学和材料科学的知识，进行多步计算和概念关联。虽然题目给出了部分参数，但仍需要考生具备较强的综合分析能力来正确解答。", "convertible": true, "correct_option": "v = 0.367", "choice_question": "A cylindrical specimen of a metal alloy 10 mm in diameter is stressed elastically in tension. A force of 15,000N produces a reduction in specimen diameter of 7 × 10^{-3} mm. Compute Poisson's ratio for this material if its elastic modulus is 100 GPa. The Poisson's ratio is:", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion to a multiple-choice format. The correct option can be directly derived from the given answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.367", "B": "0.275", "C": "0.420", "D": "0.183" }, "correct_answer": "A", "explanation": "正确答案A(0.367)通过精确计算轴向应变(σ/E)和横向应变(Δd/d₀)得出。干扰项B(0.275)利用弹性模量计算错误(误用剪切模量公式)，C(0.420)基于常见金属的直觉值但忽略具体条件，D(0.183)通过错误转换单位(英制与公制混淆)产生。这些干扰项分别针对材料参数混淆、专业直觉陷阱和单位转换错误设计。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 999, "question": "Please analyze the characteristics and mechanisms of grain refinement strengthening.", "answer": "Grain refinement strengthening: It is caused by the increase in the number of grains and the decrease in their size, which increases the resistance to continuous dislocation slip, leading to strengthening. At the same time, the dispersion of slip also enhances plasticity. This strengthening mechanism is the only one that can simultaneously increase both strength and plasticity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析晶粒细化强化的特点和机制，需要详细的文字解释和论述，而不是选择、判断或计算。答案也提供了详细的解释，符合简答题的特征。 | 知识层次: 题目要求分析晶粒细化强化的特性和机制，涉及对材料科学中强化机理的深入理解和解释，需要综合运用相关知识进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求分析晶粒细化强化的特性和机理，涉及多个复杂概念的整合，包括晶粒数量增加、尺寸减小对位错滑移阻力的影响，以及滑移分散对塑性的增强作用。此外，题目还强调这是唯一能同时提高强度和塑性的强化机制，需要考生具备深入的材料科学知识，能够进行综合分析和机理解释。这种题目不仅测试知识点的记忆，更考察对复杂现象的理解和推理能力，因此在选择题型中属于最高难度。", "convertible": true, "correct_option": "Grain refinement strengthening: It is caused by the increase in the number of grains and the decrease in their size, which increases the resistance to continuous dislocation slip, leading to strengthening. At the same time, the dispersion of slip also enhances plasticity. This strengthening mechanism is the only one that can simultaneously increase both strength and plasticity.", "choice_question": "Which of the following best describes the characteristics and mechanisms of grain refinement strengthening?", "conversion_reason": "The answer is a standard explanation of the concept, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best description of the concept.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain refinement strengthening: It is caused by the increase in the number of grains and the decrease in their size, which increases the resistance to continuous dislocation slip, leading to strengthening. At the same time, the dispersion of slip also enhances plasticity. This strengthening mechanism is the only one that can simultaneously increase both strength and plasticity.", "B": "Grain refinement strengthening occurs solely due to the reduction in grain boundary area, which decreases dislocation nucleation sites. This mechanism primarily enhances strength but inevitably reduces ductility according to the classical Hall-Petch relationship.", "C": "The strengthening effect arises from grain boundary sliding becoming the dominant deformation mechanism at nanoscale grain sizes. This unique mechanism allows simultaneous increases in both yield strength and strain hardening rate.", "D": "Grain refinement strengthening works by increasing the elastic modulus of individual grains through quantum confinement effects. The smaller grain size leads to higher stiffness, which directly translates to greater strength while maintaining ductility." }, "correct_answer": "A", "explanation": "Option A is correct as it accurately describes the dual effect of grain refinement on both strength (via dislocation blocking) and plasticity (via slip dispersion). Option B incorrectly states that ductility always decreases, ignoring cases where refined grains improve ductility. Option C introduces the incorrect mechanism of grain boundary sliding dominating at small scales. Option D falsely attributes the effect to quantum confinement and modulus changes, which are irrelevant to conventional grain refinement strengthening.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 728, "question": "Most solid-phase reactions are controlled by the diffusion rate.", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（用×表示错误），符合判断题的特征 | 知识层次: 题目考查对固相反应控制因素这一基本概念的记忆和理解，属于基础概念记忆范畴 | 难度: 在选择题型中属于基本概念正误判断，仅需记忆固体相反应通常由扩散速率控制这一基本原理即可判断正误，无需深入理解或分析复杂概念。", "convertible": true, "correct_option": "×", "choice_question": "Most solid-phase reactions are controlled by the diffusion rate.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All solid-phase reactions at temperatures above 0.8 Tm are primarily diffusion-controlled.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many solid-phase reactions become diffusion-controlled at high temperatures (typically above 0.5 Tm), this is not universally true for all reactions above 0.8 Tm. Some reactions may still be interface-controlled or have other rate-limiting steps. The statement's use of 'all' creates an absolute claim that doesn't account for exceptions in complex material systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4935, "question": "Can a material have a positive index of refraction less than unity? Why or why not?", "answer": "In order for a material to have an index of refraction less than unity, the velocity of light in the material (v) would necessarily have to be greater than the velocity of light in a vacuum . This is not possible.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么材料不能具有小于1的正折射率，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求对折射率小于1的物理可能性进行深入分析和解释，涉及光速在介质中的传播特性与真空光速的关系，需要综合运用电磁学理论和材料光学性质的知识进行推理和论证。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "No, because the velocity of light in the material would have to be greater than the velocity of light in a vacuum, which is not possible.", "choice_question": "Can a material have a positive index of refraction less than unity?", "conversion_reason": "The answer is a standard explanation that can be converted into a correct option for a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because the phase velocity of light cannot exceed c in any material", "B": "Yes, in certain metamaterials with engineered negative permeability", "C": "Yes, in highly anisotropic crystals where the effective refractive index varies with direction", "D": "Yes, near absorption resonances where the real part of refractive index can dip below unity" }, "correct_answer": "A", "explanation": "Correct answer A is based on fundamental relativistic constraints where phase velocity can never exceed c. Option B exploits confusion between positive/negative index materials. Option C uses anisotropy as a plausible but irrelevant factor. Option D traps those who mistake the real part of complex refractive index near resonances for the actual refractive index governing light propagation speed.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3285, "question": "Under what conditions can austenite transform into lamellar pearlite?", "answer": "When the austenitizing temperature is high, the holding time is long, the composition of austenite is uniform, and the cooling rate is fast, lamellar pearlite is prone to form.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释在什么条件下奥氏体可以转变为层状珠光体，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释奥氏体转变为层状珠光体的条件，涉及多个因素（温度、时间、成分均匀性、冷却速率）的综合分析，需要理解相变原理并关联实际工艺条件，属于中等应用层次。 | 难度: 在选择题型内，该题目属于较高难度。题目要求考生不仅掌握奥氏体向层状珠光体转变的基本条件，还需要综合分析多个因素（奥氏体化温度、保温时间、成分均匀性和冷却速率）之间的相互作用。这种多因素关联分析在选择题中属于较复杂的思维过程，需要考生具备较强的概念整合能力和综合分析能力，因此属于等级4难度。", "convertible": true, "correct_option": "When the austenitizing temperature is high, the holding time is long, the composition of austenite is uniform, and the cooling rate is fast, lamellar pearlite is prone to form.", "choice_question": "Under what conditions can austenite transform into lamellar pearlite?", "conversion_reason": "The answer is a standard and specific condition, which can be directly used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When the austenitizing temperature is high, the holding time is long, the composition of austenite is uniform, and the cooling rate is fast", "B": "When the austenitizing temperature is low, the holding time is short, the composition is heterogeneous, and the cooling rate is slow", "C": "When the carbon content exceeds 2.1% and the cooling rate matches the TTT diagram's nose region", "D": "When the material is first quenched to form martensite, then tempered at 600°C for 2 hours" }, "correct_answer": "A", "explanation": "Correct answer A describes the precise conditions for lamellar pearlite formation: high temperature and long holding time ensure complete austenitization, uniform composition prevents other phases, and fast cooling enables diffusion-controlled pearlite formation. Option B reverses all critical parameters, creating a cognitive bias trap. Option C misleads by introducing carbon percentage (irrelevant to pearlite formation) and TTT diagram nose region (which actually prevents pearlite). Option D exploits confusion between tempering martensite and austenite decomposition pathways.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2631, "question": "Given that the relative atomic mass of Si is 28.09, if there are 5×10^10 electrons capable of free movement in 100g of Si, calculate the proportion of covalent bonds that must be broken.", "answer": "Number of covalent bonds = number of atoms = 2.144 × 10^24; Number of covalent bonds to be broken = (5 × 10^10) / 2 = 2.5 × 10^10; Proportion = (2.5 × 10^10) / (2.144 × 10^24) = 1.166 × 10^-14", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，包括计算共价键的数量、需要断裂的共价键数量以及比例。答案也是通过具体的计算步骤得出的数值结果。 | 知识层次: 题目需要进行多步计算，包括计算硅的原子数、自由电子数与共价键断裂数的关系，以及最终的比例计算。这需要理解硅的原子结构、共价键的性质以及自由电子的来源，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解相对原子质量、自由电子与共价键的关系，并进行多步计算（包括摩尔计算、比例计算等）。虽然题目提供了具体数值，但解题步骤涉及概念关联和综合分析，对学生的应用能力要求较高。", "convertible": true, "correct_option": "1.166 × 10^-14", "choice_question": "Given that the relative atomic mass of Si is 28.09, if there are 5×10^10 electrons capable of free movement in 100g of Si, what is the proportion of covalent bonds that must be broken?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.166 × 10^-14", "B": "5.83 × 10^-15", "C": "2.332 × 10^-14", "D": "1.166 × 10^-12" }, "correct_answer": "A", "explanation": "The correct answer is calculated by first determining the number of Si atoms in 100g (100/28.09 × Avogadro's number), then recognizing each broken covalent bond provides 2 free electrons. The proportion is (5×10^10 electrons)/(2 × total Si atoms). Option B is half the correct value, exploiting the common error of forgetting each bond provides 2 electrons. Option C is double the correct value, targeting those who might incorrectly double-count bonds. Option D introduces an order-of-magnitude error by misplacing the decimal, a common calculation mistake in exponential notation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2877, "question": "Briefly describe the driving forces of primary recrystallization and secondary recrystallization", "answer": "The driving force of primary recrystallization is the elastic distortion energy of the matrix, while the driving force of secondary recrystallization comes from the reduction of interfacial energy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述两种再结晶的驱动力，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对初级再结晶和次级再结晶驱动力的基本概念记忆和理解，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个不同的概念（初级再结晶和次级再结晶），但正确选项直接给出了两者的驱动力定义，不需要复杂的推理或比较分析。考生只需准确记忆并区分这两个概念的基本原理即可作答。因此，该题目属于\"概念解释和描述\"层次，对应难度等级2。", "convertible": true, "correct_option": "The driving force of primary recrystallization is the elastic distortion energy of the matrix, while the driving force of secondary recrystallization comes from the reduction of interfacial energy.", "choice_question": "Which of the following correctly describes the driving forces of primary recrystallization and secondary recrystallization?", "conversion_reason": "The answer is a standard description that can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description among possible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The driving force of primary recrystallization is the elastic distortion energy of the matrix, while the driving force of secondary recrystallization comes from the reduction of interfacial energy", "B": "Both primary and secondary recrystallization are driven by the reduction of dislocation density, with secondary recrystallization requiring higher activation energy", "C": "Primary recrystallization is driven by surface energy minimization, while secondary recrystallization is driven by grain boundary curvature", "D": "The driving forces for both processes originate from stored strain energy, with secondary recrystallization occurring at higher temperatures" }, "correct_answer": "A", "explanation": "Correct answer A precisely distinguishes the different driving forces: elastic distortion energy for primary recrystallization (stored energy from dislocations) vs interfacial energy reduction for secondary recrystallization (grain growth). Option B is a common misconception that overemphasizes dislocation density for both processes. Option C reverses the typical energy considerations by attributing surface energy to primary recrystallization. Option D creates confusion by suggesting identical origins at different temperatures, ignoring the fundamental difference in driving mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4588, "question": "A parallel-plate capacitor using a dielectric material having an \\varepsilon_{r} of 2.5 has a plate spacing of 1 mm (0.04 in.). If another material having a dielectric constant of 4.0 is used and the capacitance is to be unchanged, what must be the new spacing between the plates?", "answer": "the new spacing between the plates must be 1.6 mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要通过数值计算和公式应用来解决问题，涉及电容器的参数变化和计算新的板间距。答案是一个具体的数值结果（1.6 mm），而不是选择、判断或文字解释。 | 知识层次: 题目涉及基本的电容公式应用和简单计算，只需要理解电容与介电常数和板间距的关系，并进行一步计算即可得出结果。不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。题目要求考生理解平行板电容器的基本公式（C = εA/d），并能够根据给定的介电常数变化调整板间距以保持电容不变。虽然涉及两个不同的介电常数，但计算步骤直接且无需复杂的推导或分析，属于简单应用层次。", "convertible": true, "correct_option": "1.6 mm", "choice_question": "A parallel-plate capacitor using a dielectric material having an \\varepsilon_{r} of 2.5 has a plate spacing of 1 mm (0.04 in.). If another material having a dielectric constant of 4.0 is used and the capacitance is to be unchanged, what must be the new spacing between the plates?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.6 mm", "B": "0.625 mm", "C": "2.5 mm", "D": "4.0 mm" }, "correct_answer": "A", "explanation": "The correct answer is A (1.6 mm) because capacitance is directly proportional to dielectric constant and inversely proportional to plate spacing. To maintain the same capacitance when increasing εr from 2.5 to 4.0, the spacing must increase by a factor of 4.0/2.5 = 1.6. Option B (0.625 mm) is a common error from incorrectly inverting the ratio. Option C (2.5 mm) exploits confusion with the original dielectric constant value. Option D (4.0 mm) directly uses the new dielectric constant as the spacing, creating a tempting but incorrect proportional relationship.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 918, "question": "4.Deformation texture", "answer": "The phenomenon of crystallographic orientation preference occurring during polycrystalline deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Deformation texture\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对\"Deformation texture\"这一基本概念的定义和现象描述，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对\"变形织构\"这一基础概念的定义记忆，属于最基础的定义简答级别。正确选项直接给出了该术语的准确定义，不需要任何解释、分析或推理过程，完全符合选择题型中最简单的难度标准。", "convertible": true, "correct_option": "The phenomenon of crystallographic orientation preference occurring during polycrystalline deformation.", "choice_question": "Which of the following best describes deformation texture?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phenomenon of crystallographic orientation preference occurring during polycrystalline deformation", "B": "The change in material density caused by plastic deformation processes", "C": "The alignment of dislocations along specific slip systems during elastic deformation", "D": "The macroscopic surface pattern formation during high-temperature creep" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines deformation texture as the preferred crystallographic orientation developed during plastic deformation of polycrystalline materials. Option B exploits density change misconception (cognitive bias). Option C combines truth (dislocation alignment) with false context (elastic deformation). Option D uses real phenomenon (creep) but wrong context (surface patterns vs crystallography).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4742, "question": "An aluminum bar 125mm (5.0 in.) long and having a square cross section 16.5mm (0.65 in.) on an edge is pulled in tension with a load of 66,700N(15,000 lb) and experiences an elongation of 0.43 mm(1.7 × 10^{-2} in.). Assuming that the deformation is entirely elastic, calculate the modulus of elasticity of the aluminum.", "answer": "the modulus of elasticity of the aluminum is 71.2 gpa (10.4 × 10^{6} psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的参数（长度、截面积、载荷、伸长量）进行数值计算，应用胡克定律公式来求解铝的弹性模量。答案是一个具体的数值计算结果，符合计算题的特征。 | 知识层次: 题目要求应用基本公式（胡克定律）进行简单的弹性模量计算，涉及直接套用公式和单位换算，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用胡克定律和应力应变公式，但计算步骤直接且无需复杂推导。题目明确给出了所有必要参数，只需套用公式即可得出答案，属于基础应用层次。", "convertible": true, "correct_option": "71.2 GPa (10.4 × 10^{6} psi)", "choice_question": "An aluminum bar 125mm (5.0 in.) long and having a square cross section 16.5mm (0.65 in.) on an edge is pulled in tension with a load of 66,700N(15,000 lb) and experiences an elongation of 0.43 mm(1.7 × 10^{-2} in.). Assuming that the deformation is entirely elastic, the modulus of elasticity of the aluminum is:", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, which can be converted into a multiple-choice question format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "71.2 GPa (10.4 × 10^{6} psi)", "B": "35.6 GPa (5.2 × 10^{6} psi)", "C": "142.4 GPa (20.8 × 10^{6} psi)", "D": "107.8 GPa (15.6 × 10^{6} psi)" }, "correct_answer": "A", "explanation": "The correct answer is A (71.2 GPa) calculated using Hooke's Law (E = σ/ε) with σ = F/A and ε = ΔL/L. B is half the correct value, exploiting the common mistake of not squaring the edge length when calculating cross-sectional area. C is double the correct value, targeting those who confuse total elongation with strain. D is a realistic but incorrect value for aluminum alloys, exploiting material class confusion between pure aluminum and high-strength alloys.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 629, "question": "How to improve the strength of solid solution alloys?", "answer": "Solid solution strengthening, work hardening, grain refinement strengthening, precipitation strengthening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来回答如何提高固溶体合金的强度，答案提供了多种方法但没有具体选项或计算步骤。 | 知识层次: 题目要求列举并解释提高固溶体合金强度的几种方法，涉及多个强化机制（固溶强化、加工硬化、晶粒细化强化、沉淀强化）的综合应用。虽然不需要深入分析每种机制的微观机理，但需要理解这些机制的基本原理及其在材料强化中的作用，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握固体溶液合金强度提升的多种方法，包括固溶强化、加工硬化、晶粒细化强化和沉淀强化等概念。虽然题目提供了正确选项，但考生需要对这些概念有一定的理解和区分能力，才能正确选择。这涉及到中等应用层次的知识，需要考生进行概念关联和综合分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Solid solution strengthening, work hardening, grain refinement strengthening, precipitation strengthening", "choice_question": "Which of the following methods can improve the strength of solid solution alloys?", "conversion_reason": "The answer is a standard list of methods, which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Introducing coherent precipitates with lattice mismatch < 5%", "B": "Increasing the dislocation density through rapid quenching", "C": "Adding elements with identical atomic radii to the matrix", "D": "Applying high-temperature annealing to relieve internal stresses" }, "correct_answer": "A", "explanation": "Correct answer A is valid because coherent precipitates with small lattice mismatch create strain fields that impede dislocation motion. Option B is a cognitive bias trap - while dislocation density increases strength, rapid quenching typically introduces residual stresses rather than controlled dislocation networks. Option C exploits material science intuition by suggesting identical atomic radii would prevent strengthening, when in fact some size difference is needed for solid solution strengthening. Option D is a multi-level verification trap where high-temperature annealing does relieve stresses but actually decreases strength by reducing dislocation density.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4356, "question": "The kinetics of the austenite-to-pearlite transformation obey the Avrami relationship. Using the fraction transformed-time data given here, determine the total time required for 95% of the austenite to transform to pearlite:\n\\begin{tabular}{cc}\n\\hline Fraction Transformed & Time (s) \\\\\n\\hline 0.2 & 12.6 \\\\\n0.8 & 28.2 \\\\\n\\hline\n\\end{tabular}", "answer": "35.7(s)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求使用给定的数据和Avrami关系式进行数值计算，以确定95%奥氏体转变为珠光体所需的总时间。答案是一个具体的数值（35.7秒），这表明解答过程涉及公式应用和计算步骤。 | 知识层次: 题目需要应用Avrami关系进行多步计算，涉及数据分析和公式推导，要求将给定的分数转换-时间数据关联起来，并通过计算确定总时间。这超出了简单应用的范围，但不需要复杂的机理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解Avrami动力学方程并应用给定的数据点进行多步计算。解题步骤包括：1) 根据给定的两个数据点建立方程组求解Avrami方程中的参数；2) 利用求解出的参数计算95%转变所需的时间。虽然题目提供了部分数据简化了计算，但仍需要综合运用数学和材料科学知识进行推导和计算。", "convertible": true, "correct_option": "35.7 s", "choice_question": "The kinetics of the austenite-to-pearlite transformation obey the Avrami relationship. Using the fraction transformed-time data given here, determine the total time required for 95% of the austenite to transform to pearlite:", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "35.7 s", "B": "42.3 s", "C": "28.2 s", "D": "56.8 s" }, "correct_answer": "A", "explanation": "The correct answer is A (35.7 s) as it is derived from solving the Avrami equation using the given data points. Option B (42.3 s) is designed to exploit cognitive bias by presenting a value close to the correct answer but derived from incorrect assumptions about linearity. Option C (28.2 s) is a professional intuition trap, using the time value from the data table where transformation is 80% complete, tempting those who might assume this represents near-completion. Option D (56.8 s) is a multi-level verification trap, appearing to follow a plausible exponential trend but actually doubling the correct time value.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2170, "question": "What is single slip? What are the characteristics of its slip lines?", "answer": "Single slip refers to the slip occurring on only one slip system. The slip lines appear as a series of parallel straight lines. This is because in single slip, only one set of slip systems is active, where all slip planes are parallel to each other and the slip directions are identical.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"single slip\"及其滑移线特征进行文字解释和论述，答案提供了详细的定义和特征描述，符合简答题的特点。 | 知识层次: 题目考查对单滑移及其滑移线特征的基本概念记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生不仅知道单滑移的定义，还要理解其滑移线的特征。正确选项中对单滑移的解释和滑移线特征的描述较为详细，要求考生具备一定的概念理解和描述能力，而不仅仅是简单的定义记忆。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "Single slip refers to the slip occurring on only one slip system. The slip lines appear as a series of parallel straight lines. This is because in single slip, only one set of slip systems is active, where all slip planes are parallel to each other and the slip directions are identical.", "choice_question": "Which of the following correctly describes single slip and its slip lines?", "conversion_reason": "The answer is a standard definition and description, which can be converted into a multiple-choice question format by presenting it as the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Single slip occurs on one slip system, producing parallel straight slip lines due to identical slip directions", "B": "Single slip involves multiple slip systems with intersecting slip lines forming cross-hatched patterns", "C": "Single slip refers to dislocation movement along the same direction but on non-parallel planes, creating wavy slip lines", "D": "Single slip occurs when dislocations move on alternating slip systems, producing zigzag slip line patterns" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes single slip's defining characteristic of operating on only one slip system, resulting in parallel lines. Option B incorrectly introduces multiple slip systems. Option C falsely suggests non-parallel planes would still qualify as single slip. Option D wrongly implies alternating slip systems could produce single slip. These exploit common misconceptions about slip system activation and slip line morphology.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4023, "question": "Complete the following statement regarding conditions that must be satisfied in order for a solid solution to exhibit extensive solubility. The solute and host species must feature [z] ability to attract electrons (electronegativity). (z = a similar, a different)", "answer": "The solute and host species must feature a similar ability to attract electrons (electronegativity).", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从两个选项（a similar, a different）中选择一个正确的单词来填空，符合选择题的特征 | 知识层次: 题目考查对固溶体溶解度条件的基本概念记忆，特别是关于溶质和溶剂电负性相似性的理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别并选择\"similar\"这一关键词即可完成作答。题目直接考察对固溶体溶解度条件的记忆，无需复杂理解或分析，属于最简单的概念识别级别。", "convertible": true, "correct_option": "a similar", "choice_question": "Complete the following statement regarding conditions that must be satisfied in order for a solid solution to exhibit extensive solubility. The solute and host species must feature [z] ability to attract electrons (electronegativity). (z = ?)", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option. It can be directly converted to a standard single-choice question by presenting the options separately.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "a similar", "B": "a significantly different", "C": "an identical", "D": "a complementary" }, "correct_answer": "A", "explanation": "The correct answer is A because extensive solid solubility requires similar electronegativity between solute and host to minimize lattice distortion. B is designed to exploit the common misconception that differences drive solubility. C is a trap for overgeneralizing the similarity requirement. D appeals to false intuition about electronic interactions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 494, "question": "What are the main morphological types of martensitic transformation products in steel?", "answer": "(2) Morphology of transformation products: lath martensite (1 point); acicular martensite. (1 point)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举和描述马氏体转变产物的主要形态类型，答案以文字解释的形式给出，符合简答题的特征。 | 知识层次: 题目考查马氏体转变产物的主要形态类型，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确区分和记忆两种不同的马氏体形态（板条马氏体和针状马氏体），而不是简单的单一概念定义。这要求考生对马氏体转变产物的分类有较清晰的理解和记忆，属于概念解释和描述的层次。", "convertible": true, "correct_option": "lath martensite and acicular martensite", "choice_question": "What are the main morphological types of martensitic transformation products in steel?", "conversion_reason": "The answer consists of standard terms (lath martensite and acicular martensite) which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "lath martensite and acicular martensite", "B": "plate martensite and twinned martensite", "C": "dislocation martensite and shear martensite", "D": "bainitic martensite and tempered martensite" }, "correct_answer": "A", "explanation": "The correct answer is A because lath and acicular are the two fundamental morphological types of martensite in steel. Option B uses real martensite terms but incorrectly pairs them as primary morphological types. Option C combines dislocation/shear mechanisms (microstructural features) with martensite naming. Option D mixes martensite with bainite and tempering processes, creating conceptually invalid combinations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 170, "question": "If 10mol% Na2O is added to SiO2, what is the calculated O:Si ratio?", "answer": "O:Si = (0.1 + 1 × 2)/1 = 2.1", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，答案是一个具体的计算结果（O:Si = 2.1），而不是选择、判断或文字解释。 | 知识层次: 题目涉及基本的化学计量计算，只需要应用简单的公式和基本的化学计量知识即可得出答案，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用基本公式进行简单计算，属于单一公式直接计算的难度等级。解题步骤简单明了，无需复杂的分析或组合多个公式。", "convertible": true, "correct_option": "O:Si = 2.1", "choice_question": "If 10mol% Na2O is added to SiO2, what is the calculated O:Si ratio?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.1", "B": "2.0", "C": "2.2", "D": "2.5" }, "correct_answer": "A", "explanation": "The correct O:Si ratio is calculated by considering that each Na2O introduces one additional oxygen atom per silicon atom in the SiO2 network. For 10mol% Na2O, the ratio becomes (2 + 0.1)/1 = 2.1. Option B (2.0) is a trap for those who forget to account for the modifier effect of Na2O. Option C (2.2) mimics common calculation errors from incorrect mole fraction application. Option D (2.5) exploits the tendency to overestimate modifier impacts in glass networks.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 655, "question": "What is work hardening?", "answer": "The phenomenon where the flow stress of a metal increases with increasing strain during cold working is called work hardening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"work hardening\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即工作硬化的定义和基本原理。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"work hardening\"的基本定义，属于最基础的概念记忆层次。正确选项直接给出了现象的定义，无需任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The phenomenon where the flow stress of a metal increases with increasing strain during cold working is called work hardening.", "choice_question": "Which of the following describes work hardening?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phenomenon where the flow stress of a metal increases with increasing strain during cold working", "B": "The increase in hardness due to precipitation of secondary phases during heat treatment", "C": "The strengthening mechanism caused by dislocation entanglement during rapid quenching", "D": "The improvement in mechanical properties resulting from grain boundary sliding at elevated temperatures" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines work hardening as the increase in flow stress with strain during cold working. Option B is incorrect as it describes precipitation hardening, not work hardening. Option C is a trap for those confusing work hardening with quench hardening. Option D describes creep behavior, exploiting confusion between room-temperature and high-temperature deformation mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4009, "question": "The mineral olivine is a solid solution of the silicate compounds forsterite \\left(Mg_{2} \\mathrm{SiO}_{4}\\right) and fayalite \\left(\\mathrm{Fe}_{2} \\mathrm{SiO}_{4}\\right).\nHow many chemical components are there in a sample of olivine?\n(a) 1\n(b) 2\n(c) 3\n(d) 4", "answer": "The components of a system are defined to be the smallest set of independently variable chemical constituents that are necessary to describe the composition of each phase that is present in a system. Components are chemically distinct. In this case, we only need to specify two things. It is convenient to simply use the compounds themselves as the components, but other options exist. For instance, specifying the amount of Mg and \\mathrm{Fe} in the system automatically fixes the \\mathrm{Si} and \\mathrm{O} content, assuming the compounds are present in their stoichiometric ratios (assuming they are defect free).", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项(a)到(d)中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对化学组分基本概念的理解和记忆，需要识别并应用组分定义来分析矿物橄榄石的组成。虽然涉及一定的逻辑推理，但主要依赖于对基础概念的掌握。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要理解“化学组分”的定义及其在具体矿物（橄榄石）中的应用。解题步骤包括识别橄榄石的组成（镁橄榄石和铁橄榄石），并理解如何根据定义确定化学组分的数量。这需要一定的概念理解和简单辨析能力，而不仅仅是直接记忆。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "b", "choice_question": "The mineral olivine is a solid solution of the silicate compounds forsterite (Mg₂SiO₄) and fayalite (Fe₂SiO₄). How many chemical components are there in a sample of olivine?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer (b) 2, as explained in the provided answer. Therefore, it can be directly used as a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1 (only SiO₂)", "B": "2 (Mg₂SiO₄ and Fe₂SiO₄)", "C": "3 (Mg, Fe, and SiO₄)", "D": "4 (Mg, Fe, Si, and O)" }, "correct_answer": "B", "explanation": "The correct answer is B because olivine is a binary solid solution with two end-members (forsterite and fayalite) that can freely substitute for each other. Option A exploits the common misconception that solid solutions count as single components. Option C traps those who mistake independent elements for components. Option D targets those who confuse chemical species with thermodynamic components in phase rule analysis.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3732, "question": "A polymer that contains internal flaws 1mm in length fails at a stress of 25 MPa. Determine the plane strain fracture toughness of the polymer. Assume that f=1.", "answer": "the plane strain fracture toughness of the polymer is 0.99 \\text{mpa} \\sqrt{m}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（平面应变断裂韧性公式）来求解聚合物的平面应变断裂韧性，答案是一个具体的数值结果（0.99 MPa√m），符合计算题的特征。 | 知识层次: 题目需要应用基本公式（断裂韧性公式）进行简单计算，属于直接套用公式的范畴，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求直接应用平面应变断裂韧性的基本公式（K_IC = σ√(πa)），仅需代入给定的应力（25 MPa）和缺陷长度（1mm）即可得出结果。无需额外的概念理解或复杂计算步骤，属于最基础的公式套用类型。", "convertible": true, "correct_option": "0.99 MPa√m", "choice_question": "A polymer that contains internal flaws 1mm in length fails at a stress of 25 MPa. Assuming that f=1, what is the plane strain fracture toughness of the polymer?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.99 MPa√m", "B": "1.25 MPa√m", "C": "25 MPa·mm^1/2", "D": "0.44 MPa√m" }, "correct_answer": "A", "explanation": "正确答案A是通过断裂力学公式K_IC=σ√(πa)计算得出，其中σ=25 MPa，a=0.001m，f=1。干扰项B利用了常见计算错误，即忽略将mm转换为m。干扰项C使用了正确的数值但错误的单位组合，利用了材料科学中常见的单位混淆。干扰项D是通过错误地将应力值开方得到，利用了直觉性数学运算的认知偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3625, "question": "For NiO with sodium chloride structure, determine the lattice parameter.", "answer": "4.02 Å.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过计算确定NiO的晶格参数，答案是一个具体的数值（4.02 Å），这表明需要进行数值计算和公式应用来解决问题。 | 知识层次: 题目要求根据NiO的氯化钠结构确定晶格参数，这属于基本公式应用和简单计算，不需要多步计算或综合分析，仅需直接套用已知的晶格参数值即可。 | 难度: 在选择题型中，该题目仅需直接应用已知的晶格参数值（4.02 Å），无需任何计算或公式推导。属于单一知识点直接回忆的简单题目，符合等级1的难度标准。", "convertible": true, "correct_option": "4.02 Å", "choice_question": "For NiO with sodium chloride structure, the lattice parameter is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.02 Å", "B": "3.52 Å", "C": "4.17 Å", "D": "4.44 Å" }, "correct_answer": "A", "explanation": "The correct lattice parameter for NiO with sodium chloride structure is 4.02 Å (Option A). Option B (3.52 Å) is a common trap as it matches the lattice parameter of pure nickel, exploiting the cognitive bias of associating NiO with its parent metal. Option C (4.17 Å) is designed to catch those who might confuse it with similar oxides like CoO, leveraging professional intuition about transition metal oxides. Option D (4.44 Å) appears plausible as it's close to the values seen in some other rock-salt structures, creating a multi-level verification trap where surface-level similarity overrides precise knowledge.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1393, "question": "Calculate the coordination number of the cation in the compound Cr2O3, given r(Cr3+)=0.064nm, r(O2-)=0.132nm", "answer": "6", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（离子半径比）来确定配位数，答案是一个具体的数值结果（6），符合计算题的特征。 | 知识层次: 题目要求计算Cr2O3中阳离子的配位数，涉及离子半径比的计算和配位数判断，属于基本公式应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题中属于简单公式应用计算难度。题目要求计算Cr2O3中阳离子的配位数，给出了Cr3+和O2-的离子半径，可以直接应用配位数与离子半径比的关系公式进行计算。虽然需要记忆和理解配位数与半径比的关系，但计算过程简单直接，属于基本公式应用和简单计算的范畴。", "convertible": true, "correct_option": "6", "choice_question": "What is the coordination number of the cation in the compound Cr2O3, given r(Cr3+)=0.064nm, r(O2-)=0.132nm?", "conversion_reason": "The answer to the calculation question is a specific numerical value, which can be directly used as the correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6 (octahedral coordination)", "B": "4 (tetrahedral coordination)", "C": "8 (cubic coordination)", "D": "12 (close-packed coordination)" }, "correct_answer": "A", "explanation": "The correct answer is A (6) because the radius ratio (r+/r-) is 0.064/0.132=0.485, which falls in the range of 0.414-0.732 for octahedral coordination. B is a cognitive bias trap - while 4 is common for many oxides, the radius ratio clearly indicates octahedral. C exploits the 'bigger is better' intuition but exceeds the radius ratio limit. D is a professional intuition trap - while 12 occurs in metals, it's impossible with this radius ratio in ionic compounds.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 1, "correct_answers": 1, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2741, "question": "It is known that liquid pure nickel undergoes homogeneous nucleation at an undercooling of 319°C under 1.013×10^5 Pa (1 atm). Given the critical nucleus radius as 1 nm, the melting point of pure nickel as 1726 K, the heat of fusion Lm = 18075 J/mol, and the molar volume V = 6.6 cm^3/mol, calculate the liquid-solid interfacial energy and the critical nucleation work for pure nickel.", "answer": "Since r* = 2σ/ΔGv = 2σTm/LmΔT = 2σTm V/ΔHmΔT, and for solidification, ΔGv = LmΔT/Tm, thus σ = r*ΔGv/2V = r*ΔHmΔT/2VTm = 1×10^-7 × 18075 × 319 / 2 × 1726 × 6.6 = 2.53×10^-5 (J/cm^2) = 0.253 (J/m^2). ΔG* = 16πσ^3Tm^2Vs^2 / 3ΔHm^2ΔT^2 = 16 × 3.14 × (2.53×10^-5)^3 × 1726^2 × 6.6^2 / 3 × 18075^2 × 319^2 = 1.06×10^-18 (J).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及多个物理量的计算和推导，最终需要得出具体的数值结果。答案中展示了详细的公式应用和计算步骤，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及多个公式的应用和概念关联，如临界核半径、熔化热、摩尔体积等，需要综合分析并正确代入数值进行计算。虽然不涉及复杂的推理分析或机理解释，但计算过程较为复杂，超出了简单应用的范围。 | 难度: 在选择题中属于高难度题目，需要综合运用多个热力学和材料科学概念（如均相成核、临界核半径、界面能等），并进行多步骤的复杂计算。题目涉及多个变量的转换和单位统一（如J/cm²到J/m²的转换），且需要正确应用公式推导过程。这种题目在选择题型中属于需要深度理解和较强计算能力的类型，远超基础概念题和简单计算题的难度水平。", "convertible": true, "correct_option": "0.253 (J/m^2)", "choice_question": "It is known that liquid pure nickel undergoes homogeneous nucleation at an undercooling of 319°C under 1.013×10^5 Pa (1 atm). Given the critical nucleus radius as 1 nm, the melting point of pure nickel as 1726 K, the heat of fusion Lm = 18075 J/mol, and the molar volume V = 6.6 cm^3/mol, the liquid-solid interfacial energy for pure nickel is:", "conversion_reason": "The question involves a calculation with a specific numerical answer, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.253 J/m²", "B": "0.319 J/m²", "C": "0.1726 J/m²", "D": "0.18075 J/m²" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算得到的液体-固体界面能。干扰项B直接使用了过冷度数值319°C，利用认知偏差让答题者误以为可以直接使用这个数值。干扰项C使用了熔点1726 K的数值，利用了单位转换陷阱。干扰项D直接采用了熔化热18075 J/mol的数值，利用了材料参数混淆策略。这些干扰项都利用了材料科学中常见的数值直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1859, "question": "In the face-centered cubic close-packed structure of the NaCl unit cell, how many octahedral voids are there?", "answer": "There are a total of 4 octahedral voids in the NaCl unit cell.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求回答一个具体的问题，答案需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目考查对晶体结构中八面体空隙数量的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（NaCl晶胞中的八面体空隙数量），但需要学生对面心立方紧密堆积结构有清晰的理解，并能准确计算空隙数量。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。", "convertible": true, "correct_option": "4", "choice_question": "In the face-centered cubic close-packed structure of the NaCl unit cell, how many octahedral voids are there?", "conversion_reason": "The answer is a specific numerical value, which can be directly used as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "4", "C": "选项D", "D": "选项B" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 2066, "question": "Point out the errors in the following concepts and correct them: (3) At any temperature, the maximum structural fluctuations appearing in liquid metals are all embryos.", "answer": "In undercooled liquids, the maximum structural fluctuations appearing in liquid metals are all embryos.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目考查对液体金属中结构波动和胚胎形成的基本概念的理解和记忆，需要识别并纠正错误表述，属于基础概念层面的认知要求。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生不仅记住定义，还要能够识别并纠正错误概念。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。", "convertible": true, "correct_option": "In undercooled liquids, the maximum structural fluctuations appearing in liquid metals are all embryos.", "choice_question": "Which of the following correctly identifies and corrects the error in the concept: 'At any temperature, the maximum structural fluctuations appearing in liquid metals are all embryos.'?", "conversion_reason": "The original short answer question asks for a correction of a specific concept, which can be rephrased into a multiple-choice format by presenting the correct statement as one of the options. The answer is a standard and precise statement, making it suitable for conversion.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In undercooled liquids, the maximum structural fluctuations appearing in liquid metals are all embryos.", "B": "At critical undercooling, the maximum structural fluctuations appearing in liquid metals are all nuclei.", "C": "Above melting temperature, the maximum structural fluctuations appearing in liquid metals are all embryos.", "D": "At any undercooling, the maximum structural fluctuations appearing in liquid metals are all nuclei." }, "correct_answer": "A", "explanation": "The correct answer is A because embryos are the precursor to nuclei formation and only appear in undercooled liquids, not at any temperature. Option B is incorrect because at critical undercooling, fluctuations become nuclei, not embryos. Option C is wrong as embryos cannot form above melting temperature. Option D is incorrect because it ignores the temperature dependence of embryo formation and incorrectly states all fluctuations become nuclei.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3010, "question": "To which category of compounds do silicone resins and silicone rubbers belong? Options: A. Carbon-chain organic polymers B. Heterochain organic polymers C. Element-organic compounds D. Inorganic polymers", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的四个选项中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查对硅树脂和硅橡胶所属化合物类别的基本概念记忆，属于定义和分类的基础知识，不需要复杂的分析或应用。 | 难度: 在选择题中属于中等偏下难度，需要考生理解并区分不同类型化合物的分类标准。虽然题目涉及的是基础概念记忆，但需要对\"元素有机化合物\"的定义有明确理解，并能与其它选项(如碳链聚合物、杂链聚合物等)进行简单辨析。不需要复杂的分析过程，但比单纯记忆概念略高一个层次。", "convertible": true, "correct_option": "C. Element-organic compounds", "choice_question": "To which category of compounds do silicone resins and silicone rubbers belong?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Carbon-chain organic polymers", "B": "Heterochain organic polymers", "C": "Element-organic compounds", "D": "Inorganic polymers" }, "correct_answer": "C", "explanation": "Silicone resins and rubbers are element-organic compounds because they contain silicon (an element) bonded to organic groups (like methyl or phenyl). Option A is incorrect because while they contain organic groups, the backbone is not purely carbon-chain. Option B is a strong distractor as it suggests a heteroatom-containing polymer chain, which is partially correct but misses the key element-organic nature. Option D is incorrect because while silicon is inorganic, the presence of organic groups makes the classification inaccurate.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4836, "question": "(a) Calculate the drift velocity of electrons in silicon at room temperature and when the magnitude of the electric field is 500 V/m.", "answer": "the drift velocity of electrons in silicon at room temperature and when the magnitude of the electric field is 500 V/m is 72.5 m/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解电子在硅中的漂移速度，答案是一个具体的数值计算结果。 | 知识层次: 题目要求使用基本公式（如电子迁移率和电场的关系）进行直接计算，属于简单应用层次。虽然需要知道硅中电子迁移率的具体数值，但整体计算过程较为直接，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需要直接应用基本公式（如v_d = μE）进行简单计算，无需多个公式组合或复杂分析。题目明确给出了所有必要参数（电场强度500 V/m和硅中电子迁移率），解题步骤非常直接，属于单一公式直接计算的简单应用层次。", "convertible": true, "correct_option": "72.5 m/s", "choice_question": "What is the drift velocity of electrons in silicon at room temperature when the magnitude of the electric field is 500 V/m?", "conversion_reason": "The original question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "72.5 m/s", "B": "145 m/s", "C": "36.25 m/s", "D": "1.45 × 10^3 m/s" }, "correct_answer": "A", "explanation": "The correct answer is A (72.5 m/s) calculated using the electron mobility in silicon (1450 cm²/V·s) and the given electric field. Option B (145 m/s) doubles the correct value, exploiting the common mistake of unit conversion between cm² and m². Option C (36.25 m/s) halves the correct value, targeting those who might confuse electron and hole mobilities. Option D (1.45 × 10^3 m/s) is 20 times the correct value, designed to trap those who might misapply the mobility value directly without proper field scaling.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2035, "question": "Polyvinyl chloride eccC2H3Cl∂n is dissolved in an organic solvent, with its C-C bond length set at 0.154nm, and the number of bonds in the chain x=2n. For a molecule with a molecular mass of 28500g, what is its root mean square length?", "answer": "Root mean square length 4.65nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解根均方长度，答案是一个具体的数值结果（4.65nm），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括分子量的计算、键数的确定以及均方根长度的公式应用，涉及概念关联和综合分析。虽然不涉及复杂的推理分析或创新应用，但需要一定的计算步骤和概念理解。 | 难度: 在选择题中属于中等偏上难度，需要理解聚合物链的构象统计概念（如均方根长度公式），进行分子量到聚合度的转换计算（n=M/M0），并正确应用键长和键数关系（x=2n）。虽然题目提供了关键参数（键长0.154nm），但需要综合运用高分子物理和数学计算知识，涉及多步骤推导（包括开方运算），比单纯的概念选择题更复杂，但选项的存在降低了完全推导错误的可能性。", "convertible": true, "correct_option": "4.65nm", "choice_question": "Polyvinyl chloride (C2H3Cl)n is dissolved in an organic solvent, with its C-C bond length set at 0.154nm, and the number of bonds in the chain x=2n. For a molecule with a molecular mass of 28500g, what is its root mean square length?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.65nm", "B": "3.28nm", "C": "5.92nm", "D": "2.17nm" }, "correct_answer": "A", "explanation": "The root mean square length is calculated using the formula √(x*l²), where x is the number of bonds and l is the bond length. For PVC with molecular mass 28500g, n=28500/(62.5)=456, so x=2*456=912 bonds. The calculation gives √(912*(0.154nm)²)=4.65nm. Option B is derived by incorrectly using n instead of x. Option C results from miscalculating the number of repeat units. Option D comes from an incorrect square root calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3414, "question": "Explain the meaning of the steel grade 9SiCr", "answer": "9SiCr is a low-alloy tool steel with wc=0.9%, ws=1%, Wc=1.1%, wMn=0.45%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释钢号9SiCr的含义，答案提供了详细的文字解释和成分说明，符合简答题的特征。 | 知识层次: 题目考查对特定钢号9SiCr的基本成分和分类的记忆，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释钢号9SiCr的含义，但正确选项已经提供了具体的化学成分和分类信息，考生只需识别和匹配这些关键信息即可。这需要考生对钢号命名规则和基本合金元素有一定记忆，但不需要复杂的分析或推理过程。", "convertible": true, "correct_option": "9SiCr is a low-alloy tool steel with wc=0.9%, ws=1%, Wc=1.1%, wMn=0.45%", "choice_question": "Which of the following correctly describes the steel grade 9SiCr?", "conversion_reason": "The answer is a standard description of the steel grade, which can be converted into a multiple-choice question format by presenting it as the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "9SiCr is a low-alloy tool steel with wc=0.9%, ws=1%, Wc=1.1%, wMn=0.45%", "B": "9SiCr is a high-speed steel with wc=0.9%, wSi=1.2%, wCr=0.8%, wV=0.2%", "C": "9SiCr is a spring steel with wc=0.6%, wSi=1.8%, wCr=0.5%, wMn=0.7%", "D": "9SiCr is a bearing steel with wc=1.0%, wSi=0.3%, wCr=1.5%, wMo=0.2%" }, "correct_answer": "A", "explanation": "The correct answer is A because 9SiCr is indeed a low-alloy tool steel with the specified composition. Option B is designed to exploit the cognitive bias of associating Si and Cr with high-speed steels, while the composition is actually incorrect. Option C uses plausible spring steel composition values but misrepresents the steel type. Option D creates confusion by using typical bearing steel alloying elements (Cr, Mo) with incorrect percentages for this grade.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1340, "question": "Briefly describe the second essential reason for the high hardness of martensite: the solid solution strengthening mechanism", "answer": "Ferrite typically contains only 0.03% carbon atoms, while the carbon content in martensite is the same as that of the material itself. Therefore, martensite contains a large number of supersaturated carbon atoms, making solid solution strengthening one of the primary mechanisms for the high hardness of martensite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求简要描述马氏体高硬度的第二个主要原因，即固溶强化机制，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释马氏体高硬度的第二个主要原因——固溶强化机制，涉及对马氏体中碳原子过饱和状态的理解及其对硬度的影响。这需要将基础概念（如固溶强化）与具体材料（马氏体）的特性相结合，进行多步分析和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生理解马氏体高硬度的第二个主要原因——固溶强化机制，并能够比较铁素体和马氏体中碳含量的差异及其对硬度的影响。虽然题目涉及的知识点较为具体，但解题步骤相对直接，只需进行概念关联和综合分析即可得出正确答案。", "convertible": true, "correct_option": "Ferrite typically contains only 0.03% carbon atoms, while the carbon content in martensite is the same as that of the material itself. Therefore, martensite contains a large number of supersaturated carbon atoms, making solid solution strengthening one of the primary mechanisms for the high hardness of martensite.", "choice_question": "Which of the following describes the second essential reason for the high hardness of martensite: the solid solution strengthening mechanism?", "conversion_reason": "The answer is a standard explanation that can be converted into a correct option for a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description of the mechanism.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The high dislocation density in martensite creates strong barriers to dislocation motion, which is the primary contributor to its hardness", "B": "The tetragonal distortion of the crystal lattice due to carbon supersaturation directly increases the elastic modulus of martensite", "C": "The rapid quenching process creates nanoscale precipitates that provide Orowan strengthening", "D": "The complete absence of grain boundaries in martensite eliminates weak points for crack propagation" }, "correct_answer": "A", "explanation": "The correct answer is A because the high hardness of martensite is primarily due to its extremely high dislocation density (10^12/cm^2) creating strong barriers to dislocation motion. Option B is incorrect because while tetragonal distortion occurs, it doesn't directly affect elastic modulus. Option C is a trap as precipitation strengthening doesn't occur during quenching. Option D exploits the common misconception that martensite lacks grain boundaries, when in fact it has a complex lath or plate structure with boundaries.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1769, "question": "What are the two characteristic temperatures on the curve of glass properties changing with temperature?", "answer": "(16) Tg; (17) Tf", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答两个特征温度的名称，答案以简短的词语形式给出，不需要计算或选择，属于简答题类型 | 知识层次: 题目考查玻璃性质随温度变化的两个特征温度（Tg和Tf）的基本概念记忆，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆玻璃性质变化曲线上的两个特征温度（Tg和Tf），属于基础概念记忆的简单问题。无需解释或分析，只需直接回忆定义即可选择正确答案。", "convertible": true, "correct_option": "Tg; Tf", "choice_question": "Which of the following are the two characteristic temperatures on the curve of glass properties changing with temperature?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by listing possible options including the correct ones.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Tg and Tm (glass transition and melting temperature)", "B": "Tg and Tf (glass transition and fictive temperature)", "C": "Td and Tf (decomposition and fictive temperature)", "D": "Tm and Tf (melting and fictive temperature)" }, "correct_answer": "B", "explanation": "The correct answer is B because Tg (glass transition temperature) and Tf (fictive temperature) are the two characteristic temperatures that describe the temperature-dependent behavior of glass properties. Option A is incorrect because Tm (melting temperature) is not relevant for glass property curves. Option C is incorrect because Td (decomposition temperature) is unrelated to glass property changes. Option D is incorrect for the same reason as A, as Tm is not a characteristic temperature for glass property curves.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2022, "question": "A common polymer has C2H2Cl2 as its monomer, with an average molecular weight of 60000u (using the relative atomic masses of the elements as Ar(C)=12, Ar(H)=1, Ar(Cl)=35.5). What is its degree of polymerization?", "answer": "The degree of polymerization is n = 60000 / 97 = 620", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算（分子量计算和聚合度计算），并应用相关公式（聚合度 = 聚合物分子量 / 单体分子量）。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目考查基本的公式应用和简单计算，只需要将聚合物的平均分子量除以单体的分子量即可得到聚合度，属于直接套用公式的计算题。 | 难度: 在选择题型中，该题目仅需要直接套用基本公式（分子量除以单体分子量）进行简单计算，无需额外的概念理解或复杂步骤。属于单一公式直接计算的难度等级。", "convertible": true, "correct_option": "620", "choice_question": "A common polymer has C2H2Cl2 as its monomer, with an average molecular weight of 60000u (using the relative atomic masses of the elements as Ar(C)=12, Ar(H)=1, Ar(Cl)=35.5). What is its degree of polymerization?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "620", "B": "600", "C": "650", "D": "580" }, "correct_answer": "A", "explanation": "The correct answer is A (620) because the degree of polymerization is calculated by dividing the polymer's molecular weight (60000u) by the monomer's molecular weight (C2H2Cl2 = 12*2 + 1*2 + 35.5*2 = 97u), resulting in approximately 618.56, which rounds to 620. Option B (600) is a common error from rounding the monomer weight to 100u. Option C (650) exploits the tendency to overestimate when dealing with halogens. Option D (580) is designed to catch those who might incorrectly subtract the chlorine atoms' mass.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 387, "question": "The principle of zone refining is based on (16).", "answer": "(16) Redistribution of solute during directional solidification of solid solution (fractional crystallization)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释区域精炼的原理，答案提供了详细的文字解释，符合简答题的特征 | 知识层次: 题目考查对区域精炼原理的基本概念记忆和理解，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生准确理解\"区域精炼\"原理是基于\"固溶体定向凝固过程中溶质的再分配（分步结晶）\"这一特定概念。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。考生需要将原理名称与其具体机制正确对应，体现了对概念的理解深度。", "convertible": true, "correct_option": "Redistribution of solute during directional solidification of solid solution (fractional crystallization)", "choice_question": "The principle of zone refining is based on:", "conversion_reason": "The answer is a standard concept or term, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Redistribution of solute during directional solidification of solid solution (fractional crystallization)", "B": "Selective evaporation of impurities at high temperature zones", "C": "Electromigration of impurities under temperature gradient", "D": "Diffusion-limited segregation at moving liquid-solid interface" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental principle of zone refining where repeated melting/solidification zones redistribute solutes. Distractors exploit common misconceptions: B mimics vacuum refining, C borrows from electromigration phenomena, and D sounds plausible but misrepresents the dominant mechanism as diffusion-limited rather than partition coefficient-driven segregation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4529, "question": "Cite two differences between precipitation hardening and dispersion strengthening.", "answer": "The two differences are: (1) the hardening/strengthening effect is not retained at elevated temperatures for precipitation hardening--however, it is retained for dispersion strengthening; and (2) the strength is developed by a heat treatment for precipitation hardening--such is not the case for dispersion strengthening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求列举两种方法之间的差异，并以文字形式进行解释和论述，符合简答题的特征。答案提供了详细的文字说明，而非选择、判断或计算。 | 知识层次: 题目要求比较两种强化机制的差异，涉及对两种机制的理解和对比分析，需要一定的概念关联和综合分析能力，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求列举两种强化方式的区别，涉及对沉淀硬化和弥散强化两种机制的理解，并需要比较它们在高温下的行为差异以及强化方式的差异。这需要考生掌握相关概念并能进行综合分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "The two differences are: (1) the hardening/strengthening effect is not retained at elevated temperatures for precipitation hardening--however, it is retained for dispersion strengthening; and (2) the strength is developed by a heat treatment for precipitation hardening--such is not the case for dispersion strengthening.", "choice_question": "Which of the following correctly describes two differences between precipitation hardening and dispersion strengthening?", "conversion_reason": "The answer is a standard explanation that can be formatted as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description of the differences.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Precipitation hardening requires a coherent precipitate-matrix interface, while dispersion strengthening relies on incoherent interfaces", "B": "The strengthening particles in precipitation hardening are typically smaller than 10nm, whereas dispersion strengthening uses particles larger than 100nm", "C": "Precipitation hardening involves solute atoms clustering, while dispersion strengthening uses pre-existing second-phase particles", "D": "Precipitation hardening shows stronger temperature dependence of yield strength than dispersion strengthening" }, "correct_answer": "D", "explanation": "Correct answer D highlights the key difference in temperature dependence: precipitation hardening loses effectiveness at elevated temperatures due to precipitate dissolution/coarsening, while dispersion strengthening maintains strength. Option A is misleading because both can have coherent interfaces. Option B is incorrect as both methods use similar particle size ranges. Option C is partially true but doesn't capture the fundamental difference in temperature behavior that distinguishes the mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4215, "question": "The unit cell for tin has tetragonal symmetry, with a and b lattice parameters of 0.583 and 0.318nm, respectively. If its density, atomic weight, and atomic radius are 7.30g / {cm}^{3}, 118.69g / mol, and 0.151nm, respectively, compute the atomic packing factor.", "answer": "the atomic packing factor (apf) for tin is 0.534.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（如计算原子堆积因子）来得出具体数值结果（0.534），属于典型的计算题特征。 | 知识层次: 题目需要多步计算和概念关联，包括晶胞参数、密度、原子量、原子半径等信息的综合运用，以及原子堆积因子的计算公式应用。虽然不涉及复杂的推理分析或机理解释，但需要一定的综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及多步计算，包括晶胞体积、原子体积和原子堆积因子的计算，同时需要综合运用密度、原子量和晶格参数等概念。虽然题目提供了所有必要的数据，但解题过程需要一定的综合分析能力和对材料科学基础知识的掌握。", "convertible": true, "correct_option": "0.534", "choice_question": "The unit cell for tin has tetragonal symmetry, with a and b lattice parameters of 0.583 and 0.318nm, respectively. If its density, atomic weight, and atomic radius are 7.30g/cm³, 118.69g/mol, and 0.151nm, respectively, what is the atomic packing factor?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.534", "B": "0.612", "C": "0.465", "D": "0.689" }, "correct_answer": "A", "explanation": "正确答案0.534是通过计算单位晶胞体积与原子体积之比得出的。干扰项B(0.612)利用了面心立方结构的典型APF值来迷惑，但锡是体心四方结构。干扰项C(0.465)基于错误假设原子半径是0.140nm而非给定的0.151nm。干扰项D(0.689)故意混淆了密排六方结构的APF值，虽然数值相近但结构不同。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 831, "question": "What is the practical significance of the Kirkendall effect?", "answer": "The practical significance of the Kirkendall effect includes: ① It reveals the intrinsic connection between macroscopic diffusion laws and microscopic diffusion mechanisms, demonstrating universality; ② It directly refutes the exchange mechanism of substitutional solid solution diffusion and supports the vacancy mechanism; ③ Each component in a diffusion system has its own diffusion coefficient; ④ The Kirkendall phenomenon often produces side effects, such as incomplete shrinkage leading to Kirkendall voids, which can have adverse impacts in practice and should therefore be controlled.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Kirkendall效应的实际意义，答案提供了详细的文字论述和多个要点，符合简答题的特征。 | 知识层次: 题目要求对Kirkendall效应的实际意义进行详细解释和论述，涉及多个方面的综合分析，包括宏观与微观的联系、扩散机制的验证、扩散系数的特性以及实际应用中的副作用控制。这需要深入理解扩散机制，并能将理论知识与实际应用相结合，属于复杂分析和综合运用的层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解Kirkendall效应的基本概念，还需要综合运用多个知识点（如扩散机制、宏观与微观联系、实际应用中的副作用等）进行全面分析。正确选项涵盖了机理深度解释（等级4）和复杂现象全面分析（等级5）两个最高层次的要求，且需要考生在选择题的有限选项中识别和整合这些复杂信息。这种题目在选择题中属于对知识掌握深度和综合分析能力要求极高的类型。", "convertible": true, "correct_option": "It reveals the intrinsic connection between macroscopic diffusion laws and microscopic diffusion mechanisms, demonstrating universality; It directly refutes the exchange mechanism of substitutional solid solution diffusion and supports the vacancy mechanism; Each component in a diffusion system has its own diffusion coefficient; The Kirkendall phenomenon often produces side effects, such as incomplete shrinkage leading to Kirkendall voids, which can have adverse impacts in practice and should therefore be controlled.", "choice_question": "What is the practical significance of the Kirkendall effect?", "conversion_reason": "The answer provided is a comprehensive list of practical significances, which can be converted into a multiple-choice question format by presenting each significance as an option. However, since the original question is a short answer, it can be adapted into a multiple-choice question by rephrasing the question to ask for the correct description of the practical significance.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It demonstrates that diffusion coefficients of components in an alloy are independent of each other", "B": "It proves the exchange mechanism is the dominant diffusion process in substitutional solid solutions", "C": "It shows that vacancy diffusion can be ignored in most practical applications", "D": "It indicates that macroscopic diffusion always follows Fick's first law perfectly" }, "correct_answer": "A", "explanation": "The correct answer A captures the key insight that each component has its own intrinsic diffusion coefficient, which is a fundamental revelation of the Kirkendall effect. Option B is incorrect because the Kirkendall effect actually disproves the exchange mechanism. Option C is wrong as the effect highlights the importance of vacancy diffusion. Option D is misleading because the Kirkendall effect shows deviations from ideal Fickian behavior due to unequal diffusion rates.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4586, "question": "What is another function that a transistor may perform in an electronic circuit?", "answer": "In an electronic circuit, a transistor may act as a switching device in computers.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述晶体管在电子电路中的另一种功能，答案是一个简短的文字描述，没有提供选项或需要计算。 | 知识层次: 题目考查晶体管在电子电路中的基本功能，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆晶体管的基本功能之一（作为开关设备），属于最基础的定义性知识。题目不涉及概念解释或复杂体系，只需识别正确选项即可，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "In an electronic circuit, a transistor may act as a switching device in computers.", "choice_question": "What is another function that a transistor may perform in an electronic circuit?", "conversion_reason": "The answer is a standard description of a transistor's function, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "As a variable resistor in analog circuits", "B": "As a photon emitter in optoelectronic devices", "C": "As a piezoelectric transducer in sensors", "D": "As a superconducting element in cryogenic systems" }, "correct_answer": "A", "explanation": "The correct answer is A because transistors can indeed function as variable resistors in analog circuits through their linear operating region. Option B is a cognitive bias trap - while transistors can control light-emitting devices, they themselves do not emit photons. Option C exploits material property confusion by suggesting piezoelectric behavior which is unrelated to transistor function. Option D is a professional intuition trap, combining the valid concept of superconductivity with the incorrect application to standard transistor operation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4098, "question": "If the fiber orientation is random, which type of fibers is normally used?(a) Discontinuous(b) Continuous", "answer": "Discontinuous fibers are normally used when the fiber orientation is random.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从两个选项（Discontinuous和Continuous）中选择正确答案，符合选择题的特征。 | 知识层次: 题目考查纤维类型与取向关系的基础概念记忆，仅需识别随机取向时通常使用的纤维类型（不连续纤维），属于对材料科学基本分类知识的直接回忆。 | 难度: 在选择题型中，此题属于基础概念记忆题，只需识别\"随机取向纤维通常使用不连续纤维\"这一简单事实，无需理解或辨析其他概念，符合等级1的简单概念识别标准。", "convertible": true, "correct_option": "Discontinuous", "choice_question": "If the fiber orientation is random, which type of fibers is normally used?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly specifies the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Discontinuous fibers with aspect ratio >100", "B": "Continuous fibers with controlled alignment", "C": "Whisker-reinforced composites with nanoscale diameters", "D": "Hybrid fiber systems with bimodal length distribution" }, "correct_answer": "A", "explanation": "The correct answer is A because random fiber orientation is characteristic of discontinuous fiber composites, where the high aspect ratio (>100) ensures effective load transfer despite random distribution. Option B is incorrect because continuous fibers inherently require controlled alignment. Option C exploits nanomaterial hype but whiskers cannot achieve random orientation. Option D creates a hybrid system confusion trap, where bimodal distribution doesn't guarantee random orientation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4185, "question": "The Cl- ion has an electron structure that is identical to which inert gas?", "answer": "The Cl- ion has an electron configuration the same as argon.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释说明Cl-离子的电子结构与哪种惰性气体相同，答案需要论述和解释，而不是选择、判断或计算。 | 知识层次: 题目考查对离子电子构型与惰性气体电子构型之间关系的基本概念记忆和理解，属于基础概念记忆范畴，不需要复杂的应用或分析过程。 | 难度: 在选择题型中，该题目仅需要记忆基础概念（Cl-离子的电子结构与哪种惰性气体相同），属于基本定义简答。解题步骤简单，只需直接回忆知识点，无需复杂分析或推理。", "convertible": true, "correct_option": "argon", "choice_question": "The Cl- ion has an electron structure that is identical to which inert gas?", "conversion_reason": "The answer is a standard term (argon) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Argon", "B": "Neon", "C": "Krypton", "D": "Xenon" }, "correct_answer": "A", "explanation": "The Cl- ion gains one electron to achieve a stable electron configuration with 18 electrons, identical to argon (Ar). Neon (B) is incorrect as it has only 10 electrons. Krypton (C) and xenon (D) are heavier noble gases with more electrons, creating a cognitive bias trap where AI might associate larger ions with heavier noble gases without checking the actual electron count.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 22, "question": "According to the radius ratio relationship, what is the coordination number when Si4+ coordinates with O2-? Given rO2-=0.132nm, rSi4+=0.039nm.", "answer": "For Si4+, r+/r-=0.039/0.132=0.295; based on the relationship between cation coordination number and cation-anion radius ratio, the coordination number is 4.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求根据给定的离子半径计算半径比，并应用半径比与配位数的关系来确定配位数。解答过程涉及数值计算和公式应用，符合计算题的特征。 | 知识层次: 题目需要应用半径比关系进行简单计算，直接套用公式即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用半径比关系来确定配位数，但解题步骤相对直接，仅涉及单一公式的简单计算和直接套用。不需要复杂的推理或多步骤分析，因此难度等级为2。", "convertible": true, "correct_option": "4", "choice_question": "According to the radius ratio relationship, what is the coordination number when Si4+ coordinates with O2-? Given rO2-=0.132nm, rSi4+=0.039nm.", "conversion_reason": "The answer is a specific numerical value (4), which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4", "B": "选项D", "C": "选项B", "D": "选项C" }, "correct_answer": "A", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 403, "question": "van der Waals bond", "answer": "van der Waals bond: A physical bond formed by intermolecular attractive forces generated by instantaneous dipole moments and induced dipole moments.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对van der Waals bond进行文字解释和论述，答案是一个定义性的描述，符合简答题的特征。 | 知识层次: 题目考查van der Waals bond的基本定义和形成机制，属于基础概念的记忆和理解范畴，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆van der Waals bond的基本定义，属于基础概念记忆层次。题目直接给出了正确选项的定义，没有涉及复杂的概念体系或需要解释和描述多个相关概念。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "A physical bond formed by intermolecular attractive forces generated by instantaneous dipole moments and induced dipole moments.", "choice_question": "Which of the following best describes a van der Waals bond?", "conversion_reason": "The answer is a standard definition of a scientific term, which can be presented as one of multiple options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A physical bond formed by intermolecular attractive forces generated by instantaneous dipole moments and induced dipole moments", "B": "A covalent bond formed by electron sharing between hydrogen and highly electronegative atoms", "C": "A metallic bond formed by delocalized electrons in transition metal oxides", "D": "An ionic bond formed by electrostatic attraction between permanent dipoles in ceramic materials" }, "correct_answer": "A", "explanation": { "correct": "This accurately describes van der Waals bonds as weak physical interactions caused by temporary dipoles, which is the fundamental definition.", "distractors": { "B": "This describes hydrogen bonding (a specific stronger dipole interaction), exploiting the common confusion between different types of secondary bonds.", "C": "This incorrectly associates van der Waals with metallic bonding, using the 'delocalized electrons' concept that applies to both but in completely different contexts.", "D": "This mixes ionic bonding with dipole concepts, creating a plausible-sounding but fundamentally wrong definition that could trap those recalling ceramic bonding mechanisms." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2734, "question": "In an aluminum specimen, the dislocation density within the grains was measured to be 5×10^9/cm². Assuming all dislocations are concentrated on the subgrain boundaries; each subgrain has a regular hexagonal cross-section. The misorientation angle between subgrains is 5°, and if all dislocations are edge dislocations with b = a/2 [101], the magnitude of the Burgers vector is equal to 2×10^-10 m. Calculate the dislocation spacing on the subgrain boundary.", "answer": "D = b / (2 sin(θ/2)) ≈ b / θ = (2×10^-10) / 0.087 = 23×10^-10 m", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及具体的数学运算和物理公式推导，最终给出一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括应用Burgers矢量和位错间距的公式，同时需要理解位错密度、亚晶界和位错类型之间的关系。虽然不涉及复杂的综合分析或创新应用，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解位错密度、亚晶界取向差、伯格斯矢量等多个材料科学概念，并应用公式进行多步骤计算（包括角度转换和单位统一）。虽然题目提供了关键公式，但考生仍需正确识别和应用这些概念才能得出答案。", "convertible": true, "correct_option": "23×10^-10 m", "choice_question": "In an aluminum specimen, the dislocation density within the grains was measured to be 5×10^9/cm². Assuming all dislocations are concentrated on the subgrain boundaries; each subgrain has a regular hexagonal cross-section. The misorientation angle between subgrains is 5°, and if all dislocations are edge dislocations with b = a/2 [101], the magnitude of the Burgers vector is equal to 2×10^-10 m. What is the dislocation spacing on the subgrain boundary?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "23×10^-10 m", "B": "11.5×10^-10 m", "C": "46×10^-10 m", "D": "5.75×10^-10 m" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the relationship between misorientation angle (θ), Burgers vector magnitude (b), and dislocation spacing (D): θ = b/D. For θ=5° (0.0873 rad) and b=2×10^-10 m, D = b/θ = 23×10^-10 m. Option B incorrectly halves the correct spacing. Option C doubles the correct spacing, a common error when misapplying the angle conversion. Option D divides by 4π instead of the angle in radians, exploiting unit confusion traps.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2965, "question": "According to the Hall-Petch equation σ=σ₀+kd⁻¹/², given that when annealed for 30 minutes σ=112MPa, d=23μm, and when annealed for 60 minutes σ=103MPa, d=32.5μm, find the values of the constants σ₀ and k.", "answer": "Set up the system of equations: 112MPa = σ₀ + k×(23μm)⁻¹/² 103MPa = σ₀ + k×(32.5μm)⁻¹/² The solutions are: σ₀ = 55.3MPa, k = 272MPa·μm¹/²", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的数据和公式进行数值计算，求解常数σ₀和k的值，答案也是通过计算得出的具体数值。 | 知识层次: 题目需要应用Hall-Petch方程进行多步计算，涉及建立方程组和求解未知数，需要一定的综合分析能力，但不需要复杂的推理或创新思维。 | 难度: 在选择题中属于中等偏上难度，需要建立并解二元一次方程组，涉及材料科学中的Hall-Petch方程应用。解题步骤包括：1)正确理解方程中各参数含义；2)将给定数据代入建立两个方程；3)进行包含分数指数的计算；4)解方程组求两个未知数。虽然选择题提供了正确选项，但仍需较强的计算能力和概念理解才能验证答案的正确性。", "convertible": true, "correct_option": "σ₀ = 55.3MPa, k = 272MPa·μm¹/²", "choice_question": "According to the Hall-Petch equation σ=σ₀+kd⁻¹/², given that when annealed for 30 minutes σ=112MPa, d=23μm, and when annealed for 60 minutes σ=103MPa, d=32.5μm, which of the following are the correct values of the constants σ₀ and k?", "conversion_reason": "The problem provides a specific numerical answer, making it suitable for conversion into a multiple-choice format where the correct option is the provided solution.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "σ₀ = 55.3MPa, k = 272MPa·μm¹/²", "B": "σ₀ = 72.1MPa, k = 198MPa·μm¹/²", "C": "σ₀ = 48.6MPa, k = 305MPa·mm¹/²", "D": "σ₀ = 63.8MPa, k = 225MPa·μm⁻¹/²" }, "correct_answer": "A", "explanation": "The correct answer is A because it satisfies both given conditions when substituted into the Hall-Petch equation. Option B uses plausible values but fails to match the experimental data. Option C introduces a unit trap by using mm instead of μm, which is a common oversight. Option D incorrectly inverts the exponent in the units for k, exploiting a common sign error in interpreting the equation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3338, "question": "After heating T8 steel wire to 870°C and holding for 1h, indicate its phase and composition.", "answer": "Austenite, w_C=0.77%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求描述材料的相和成分，需要文字解释和论述，而不是从选项中选择或进行数值计算 | 知识层次: 题目考查对T8钢在特定热处理条件下的相和成分的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（T8钢的相变温度和成分），但需要考生准确记忆T8钢在特定温度（870°C）下的相变结果（奥氏体）和碳含量（0.77%）。这比单纯的定义记忆（等级1）要求更高，但不需要复杂的分析或比较（等级3）。", "convertible": true, "correct_option": "Austenite, w_C=0.77%", "choice_question": "After heating T8 steel wire to 870°C and holding for 1h, what is its phase and composition?", "conversion_reason": "The answer is a standard term and composition, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Austenite with 0.77% C", "B": "Ferrite with 0.77% C", "C": "Austenite with 0.8% C", "D": "Pearlite with 0.77% C" }, "correct_answer": "A", "explanation": "The correct answer is A because T8 steel (0.8% C) heated to 870°C will form austenite, but the carbon content in austenite at this temperature is 0.77% (from the Fe-C phase diagram), not the nominal 0.8% composition of the steel. Option B is wrong because ferrite cannot exist at this temperature with this carbon content. Option C is a common mistake where the nominal composition is incorrectly assumed to be the austenite composition. Option D is wrong because pearlite only forms below the eutectoid temperature.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3637, "question": "Based on the cesium chloride structure, determine the lattice parameter for CsBr.", "answer": "The lattice parameter a0 = 4.1916 Å.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求基于氯化铯结构确定CsBr的晶格参数，需要通过数值计算和公式应用来得出具体数值结果（4.1916 Å）。答案是一个具体的计算值，而非选择、判断或文字解释。 | 知识层次: 题目要求基于氯化铯结构计算CsBr的晶格参数，属于基本公式应用和简单计算，直接套用已知结构和计算方法即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用基本公式进行单一计算，属于最基础的难度等级。题目明确给出了结构类型（cesium chloride结构），并直接要求计算晶格参数，无需额外的概念理解或复杂的解题步骤。", "convertible": true, "correct_option": "4.1916 Å", "choice_question": "Based on the cesium chloride structure, what is the lattice parameter for CsBr?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.1916 Å", "B": "4.286 Å (using ionic radii sum without considering coordination number effects)", "C": "3.721 Å (confusing with CsCl lattice parameter)", "D": "4.512 Å (incorrectly applying NaCl structure calculation)" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the CsCl structure with proper ionic radii (Cs⁺=1.81Å, Br⁻=1.96Å) and coordination number considerations. Option B is a cognitive bias trap - it sums ionic radii directly but ignores the √3/2 factor in CsCl structure. Option C exploits professional intuition by using the well-known CsCl value. Option D is a multi-level trap applying NaCl structure math to a CsCl system.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4627, "question": "Briefly explain why amorphous polymers are transparent, while predominantly crystalline polymers appear opaque or, at best, translucent.", "answer": "Amorphous polymers are normally transparent because there is no scattering of a light beam within the material. However, for semicrystalline polymers, visible light will be scattered at boundaries between amorphous and crystalline regions since they have different indices of refraction. This leads to translucency or, for extensive scattering, opacity, except for semicrystalline polymers having very small crystallites.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释非晶态聚合物透明而结晶态聚合物不透明的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释非晶态聚合物透明而结晶态聚合物不透明的机理，涉及光散射、折射率差异等物理原理的综合分析，需要深入理解材料微观结构与光学性能的关系，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求对非晶态聚合物和结晶态聚合物的光学性质差异进行机理层面的深度解释，涉及光散射、折射率差异等复杂物理现象的综合分析。正确选项不仅需要理解两种聚合物结构的本质区别，还需要解释光散射与晶体尺寸的关系，属于复杂现象全面分析的范畴。在选择题中，这种需要多维度推理和机理解释的题目对知识掌握深度和综合分析能力要求极高。", "convertible": true, "correct_option": "Amorphous polymers are normally transparent because there is no scattering of a light beam within the material. However, for semicrystalline polymers, visible light will be scattered at boundaries between amorphous and crystalline regions since they have different indices of refraction. This leads to translucency or, for extensive scattering, opacity, except for semicrystalline polymers having very small crystallites.", "choice_question": "Why are amorphous polymers transparent, while predominantly crystalline polymers appear opaque or, at best, translucent?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Light scattering at crystalline-amorphous interfaces due to refractive index differences", "B": "Crystalline regions absorb visible light wavelengths more strongly", "C": "Amorphous polymers have higher density which prevents light scattering", "D": "Crystalline domains create charge separation that interacts with photons" }, "correct_answer": "A", "explanation": "Correct answer A identifies the key mechanism of refractive index mismatch at phase boundaries. B is incorrect because absorption isn't the primary cause - polyethylene crystals are transparent. C reverses the density relationship (crystalline regions are denser) and misattributes the mechanism. D introduces an unrelated electronic phenomenon that doesn't explain optical properties at visible wavelengths.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2329, "question": "Why are metals high-density materials?", "answer": "The bonding in metal crystals has neither directionality nor saturation requirements, so atoms are packed as closely as possible.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释金属为何是高密度材料，答案提供了文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查金属晶体结构的基本概念和键合特性的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及金属晶体结构的基本概念，但需要考生理解金属键的无方向性和无饱和性特点，并能够将这些概念与材料密度联系起来。这超出了简单的定义记忆（等级1），但尚未达到需要阐述复杂概念体系的程度（等级3）。正确选项的解释性表述也增加了题目的难度层次。", "convertible": true, "correct_option": "The bonding in metal crystals has neither directionality nor saturation requirements, so atoms are packed as closely as possible.", "choice_question": "Why are metals high-density materials?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The bonding in metal crystals has neither directionality nor saturation requirements, so atoms are packed as closely as possible", "B": "Metals have higher atomic numbers than other materials, leading to greater electron density", "C": "The metallic bond strength is directly proportional to the material density", "D": "Metals crystallize exclusively in face-centered cubic structures which maximize packing efficiency" }, "correct_answer": "A", "explanation": "Correct answer A explains the fundamental reason through metallic bonding characteristics. Distractors: B exploits the intuitive but incorrect correlation between atomic number and density (some low-Z metals like osmium are denser than high-Z metals). C creates a false proportionality between bond strength and density (tungsten has stronger bonds but lower density than gold). D uses the common but oversimplified assumption about FCC being the only dense packing (HCP is equally efficient, and some metals use BCC).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4304, "question": "Give the approximate temperature at which creep deformation becomes an important consideration for nickel.", "answer": "for ni: 418 degrees c (785 degrees f)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从多个选项中选择或判断对错，也不需要复杂的计算过程。答案是一个具体的数值，属于简答题类型。 | 知识层次: 题目考查对镍材料蠕变变形温度这一基本概念的记忆和理解，不需要复杂的计算或分析过程。 | 难度: 在选择题型中，该题目仅要求记忆镍的蠕变变形重要温度这一具体数值，属于基础概念记忆层面的简单问题。不需要解释或分析，只需直接回忆知识点即可作答，因此属于最低难度等级。", "convertible": true, "correct_option": "418 degrees C (785 degrees F)", "choice_question": "At approximately what temperature does creep deformation become an important consideration for nickel?", "conversion_reason": "The answer is a specific temperature value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "418°C (785°F)", "B": "0.4 times the melting point (491°C)", "C": "The recrystallization temperature (600°C)", "D": "The Curie temperature (358°C)" }, "correct_answer": "A", "explanation": "The correct answer is A because nickel's creep threshold is empirically established at 418°C. Option B uses a common rule-of-thumb (0.4Tm) but misapplies it by using the absolute melting point instead of the homologous temperature scale. Option C confuses creep with recrystallization phenomena. Option D exploits the nickel's magnetic transition temperature which is irrelevant to creep behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3376, "question": "What are the characteristics of the heat treatment process for high-speed steel?", "answer": "The most prominent features of the process are the very high quenching heating temperature, high tempering temperature, multiple tempering cycles, and the use of preheating during quenching heating.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释高速钢热处理过程的特征，答案提供了详细的文字描述和论述，符合简答题的特点。 | 知识层次: 题目要求解释高速钢热处理工艺的特点，涉及多个工艺参数（淬火加热温度、回火温度、多次回火循环等）的综合分析，需要理解各参数之间的关系及其对材料性能的影响，属于中等应用层次的知识。 | 难度: 在选择题中属于中等难度，需要理解高速钢热处理过程中的多个关键特征（如高淬火温度、高回火温度、多次回火循环和预热使用），并将这些概念关联起来进行综合分析。虽然题目不涉及计算，但需要对热处理工艺有较深入的理解才能正确选择答案。", "convertible": true, "correct_option": "The most prominent features of the process are the very high quenching heating temperature, high tempering temperature, multiple tempering cycles, and the use of preheating during quenching heating.", "choice_question": "Which of the following describes the characteristics of the heat treatment process for high-speed steel?", "conversion_reason": "The answer is a standard description of the process, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The most prominent features are very high quenching heating temperature, high tempering temperature, multiple tempering cycles, and preheating during quenching heating", "B": "The process primarily involves cryogenic treatment to enhance carbide precipitation, followed by single tempering at moderate temperature", "C": "Characterized by low-temperature austenitizing to prevent grain growth, with water quenching for maximum hardness", "D": "Utilizes isothermal transformation after quenching to form bainite, achieving a balance of hardness and toughness" }, "correct_answer": "A", "explanation": "Option A correctly identifies the unique heat treatment features of high-speed steel, including the need for very high temperatures (1200-1300°C) to dissolve alloy carbides, multiple tempering cycles (typically 3x) to transform retained austenite, and preheating to prevent thermal shock. Option B incorrectly suggests cryogenic treatment as primary (it's supplementary) and single tempering (insufficient for high-speed steel). Option C wrongly proposes low-temperature austenitizing (inadequate for carbide dissolution) and water quenching (would cause cracking). Option D describes a bainitic process inappropriate for tool steels requiring maximum hardness.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4447, "question": "Cite one reason why ceramic materials are, in general, harder yet more brittle than metals.", "answer": "Crystalline ceramics are harder yet more brittle than metals because they (ceramics) have fewer slip systems, and, therefore, dislocation motion is highly restricted.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求用文字解释和论述陶瓷材料比金属更硬但更脆的原因，答案提供了详细的解释，符合简答题的特征。 | 知识层次: 题目要求解释陶瓷材料比金属更硬但更脆的原因，涉及对材料微观结构（如滑移系统）和力学行为（如位错运动）之间关系的深入理解。这需要综合运用晶体结构、位错理论和材料力学性能的知识，进行机理层面的分析和解释，属于较高层次的认知要求。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Crystalline ceramics have fewer slip systems, restricting dislocation motion.", "choice_question": "Why are ceramic materials, in general, harder yet more brittle than metals?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ceramics have higher bond covalency which restricts dislocation motion", "B": "Ceramics exhibit lower thermal expansion coefficients preventing plastic deformation", "C": "The absence of free electrons in ceramics limits their ductility", "D": "Grain boundary strengthening mechanisms dominate in polycrystalline ceramics" }, "correct_answer": "A", "explanation": "Correct answer A addresses the fundamental reason through bond characteristics. B exploits thermal property confusion but expansion coefficients don't directly affect brittleness. C uses a tempting electronic structure argument that's irrelevant to hardness. D applies a valid metallurgy concept incorrectly to ceramics, creating a cross-material analogy trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2703, "question": "Calculate the actual density of α-Fe (given that for every 200 iron atoms there is 1 H atom, Ar(H)=1.008, a=0.286nm, NA=6.023×10²³)", "answer": "ρ_actual=2×(Ar(Fe)+1/200×Ar(H))/(a³×NA)=2×(55.85+1.008/200)/((2.86×10⁻⁸)³×6.023×10²³)=7.9283(g/cm³)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及原子量、晶格常数和密度计算，答案是一个具体的数值结果。 | 知识层次: 题目涉及多步计算和概念关联，需要理解晶体结构、原子质量、单位换算等知识，并进行综合分析。虽然计算过程较为直接，但需要将多个知识点结合起来，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体密度计算的基本概念（如晶格常数、原子量、阿伏伽德罗常数等），并能够正确应用公式进行多步骤计算。题目中涉及掺杂原子的修正计算（1/200氢原子），增加了问题的综合性。虽然计算过程较为复杂，但在选择题型中通过选项可以验证计算结果，降低了部分难度。", "convertible": true, "correct_option": "7.9283 g/cm³", "choice_question": "Calculate the actual density of α-Fe (given that for every 200 iron atoms there is 1 H atom, Ar(H)=1.008, a=0.286nm, NA=6.023×10²³). The correct density is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.9283 g/cm³", "B": "7.8740 g/cm³", "C": "7.9821 g/cm³", "D": "7.8655 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer A accounts for both the iron lattice and hydrogen interstitial atoms. Option B is the pure α-Fe density without hydrogen, exploiting the common oversight of impurity effects. Option C mimics a calculation error by overestimating hydrogen's impact. Option D represents a common rounding error in lattice parameter calculations, targeting numerical sensitivity.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2699, "question": "There is a glass containing soda, with a mass fraction of SiO2 at 80% and Na2O at 20%. Calculate the fraction of non-bridging O atoms.", "answer": "According to the problem, assume there is 100g of glass, containing 80g of SiO2 and 20g of Na2O. First, calculate their molar fractions: The amount of SiO2 is 80/(28.09+2×16.00)=1.331(mol) ⇒ x_SiO2=80.47%. The amount of Na2O is 20/(2×22.99+16.00)=0.323(mol) ⇒ x_Na2O=19.53%. Now, using 100mol as the basis, then: 80.47SiO2 = 80.47Si + 160.94O 19.53Na2O = 39.06Na + 19.53O Since each Na+ produces one non-bridging oxygen ion, there are 39.06 non-bridging oxygen atoms, while the bridging oxygen atoms are: (160.94 + 19.53) - 39.06 = 141.41 The fraction of non-bridging oxygen atoms is then: 39.06/180.47 = 0.216", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解非桥氧原子的比例，解答过程中涉及摩尔分数计算和化学计量关系，最终得出具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括摩尔分数的计算、非桥氧和桥氧原子的数量计算，以及最终的比例计算。虽然不涉及复杂的机理分析或创新设计，但需要综合运用化学计量和玻璃结构的基本知识，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解玻璃结构中的非桥氧和桥氧概念，并进行多步计算。题目涉及摩尔分数计算、原子平衡以及非桥氧比例的推导，步骤较为复杂，但选项提供了明确的解题路径，降低了部分难度。", "convertible": true, "correct_option": "0.216", "choice_question": "There is a glass containing soda, with a mass fraction of SiO2 at 80% and Na2O at 20%. What is the fraction of non-bridging O atoms?", "conversion_reason": "The problem involves a calculation with a definitive numerical answer, making it suitable for conversion to a multiple-choice question format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.216", "B": "0.333", "C": "0.400", "D": "0.250" }, "correct_answer": "A", "explanation": "The correct answer is A (0.216) because it accounts for the proper stoichiometric ratio of non-bridging oxygen atoms in the soda-silica glass system. Option B (0.333) is a cognitive bias trap that assumes simple molar ratio without considering network formation. Option C (0.400) is a mass fraction trap that incorrectly applies the Na2O mass percentage directly. Option D (0.250) is a symmetry bias trap that assumes equal distribution between bridging and non-bridging oxygen atoms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4483, "question": "High-density polyethylene may be chlorinated by inducing the random substitution of chlorine atoms for hydrogen. Determine the concentration of Cl (in wt%) that must be added if this substitution occurs for 5% of all the original hydrogen atoms.", "answer": "the concentration of Cl that must be added is 20.3 wt%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定氯的浓度（wt%），答案是一个具体的数值（20.3 wt%），这表明解答过程涉及计算步骤。 | 知识层次: 题目需要进行多步计算，包括确定原始氢原子的数量、计算被氯取代的氢原子数量、以及最终计算氯的质量百分比。这涉及到对材料化学组成和分子结构的理解，以及相关的数学计算能力。虽然不涉及复杂的推理或综合分析，但需要一定的概念关联和计算步骤。 | 难度: 在选择题中属于中等偏上难度，需要理解高密度聚乙烯氯化反应的概念，掌握氢原子被氯原子随机取代的化学计量关系，并进行多步计算（包括分子量计算、取代比例换算和重量百分比计算）。虽然题目给出了明确的5%取代条件，但解题过程需要综合应用化学计量学和材料组成计算的知识，属于需要概念关联和综合分析的题目。", "convertible": true, "correct_option": "20.3 wt%", "choice_question": "High-density polyethylene may be chlorinated by inducing the random substitution of chlorine atoms for hydrogen. If this substitution occurs for 5% of all the original hydrogen atoms, the concentration of Cl (in wt%) that must be added is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "20.3 wt%", "B": "5.0 wt%", "C": "35.7 wt%", "D": "10.6 wt%" }, "correct_answer": "A", "explanation": "正确答案20.3 wt%是通过计算聚乙烯分子中氢原子被5%氯原子取代后的质量百分比得出的。干扰项B利用了直觉错误，直接将5%氢原子取代率等同于重量百分比。干扰项C错误地假设了完全取代的情况。干扰项D则是忽略了氯原子与氢原子的质量差异，进行了错误的线性推算。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 637, "question": "Intermetallic compounds", "answer": "Intermetallic compounds: Compounds formed between metals and metals, or between metals and certain non-metals, whose structure and composition differ from those of the pure metals forming the intermetallic compounds. They generally exhibit characteristics such as high melting points, high hardness, and significant brittleness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Intermetallic compounds\"进行解释和论述，答案提供了详细的文字描述和特性说明，符合简答题的特征。 | 知识层次: 题目考查对金属间化合物的基本定义和特性的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项对金属间化合物的定义、组成和特性进行了较为详细的解释，需要考生对相关概念有一定的理解和记忆。相比于仅要求简单定义的选择题（等级1），该题目要求考生掌握更多的细节信息，但尚未达到需要分析复杂概念体系的程度（等级3）。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "Compounds formed between metals and metals, or between metals and certain non-metals, whose structure and composition differ from those of the pure metals forming the intermetallic compounds. They generally exhibit characteristics such as high melting points, high hardness, and significant brittleness.", "choice_question": "Which of the following best describes intermetallic compounds?", "conversion_reason": "The answer is a standard definition of intermetallic compounds, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Compounds formed between metals and metals, or between metals and certain non-metals, whose structure and composition differ from those of the pure metals forming the intermetallic compounds. They generally exhibit characteristics such as high melting points, high hardness, and significant brittleness.", "B": "Alloys formed by mixing two or more metals in any proportion, where the resulting material retains the crystal structure of the primary metal component and exhibits improved ductility compared to pure metals.", "C": "Metallic solid solutions where solute atoms randomly occupy lattice sites in the solvent metal's crystal structure, resulting in properties that are intermediate between those of the constituent elements.", "D": "Ceramic-like compounds formed exclusively between transition metals and non-metals, characterized by ionic bonding and extremely high electrical resistivity." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes intermetallic compounds as distinct chemical compounds with different structures from the parent metals, exhibiting typical properties like high melting points and brittleness. Option B incorrectly describes regular alloys rather than intermetallics, exploiting the common confusion between these concepts. Option C describes solid solutions, a cognitive bias trap since many AI models conflate intermetallics with solid solutions. Option D is a multi-level trap combining partially correct information (ceramic-like properties) with incorrect bonding description (ionic) and composition restriction (exclusively transition metals), designed to trigger false pattern recognition in AI systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3400, "question": "Analyze the special role of alloying elements (such as Cr, Si, Al, etc.) in improving the thermal stability of steel", "answer": "Alloying elements (Cr, Si, Al, etc.) form dense protective oxide films at high temperatures, preventing the oxidation of steel and thereby enhancing thermal stability.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析合金元素在提高钢的热稳定性中的特殊作用，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求分析合金元素在提高钢的热稳定性中的特殊作用，涉及多种合金元素（Cr、Si、Al等）的协同效应和机理解释，需要综合运用材料科学知识进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于机理深度解释难度。正确选项不仅要求考生识别合金元素（Cr、Si、Al等）的作用，还需要理解其形成致密氧化膜的具体机理及其对钢热稳定性的影响。这需要考生具备较深的知识储备和机理分析能力，能够将多个概念（如氧化膜形成、高温防护、热稳定性提升）综合联系起来进行推理解释。虽然题目以选择题形式呈现，但正确选项涉及的知识深度和综合推理要求使其达到等级4的难度水平。", "convertible": true, "correct_option": "Alloying elements (Cr, Si, Al, etc.) form dense protective oxide films at high temperatures, preventing the oxidation of steel and thereby enhancing thermal stability.", "choice_question": "What is the special role of alloying elements (such as Cr, Si, Al, etc.) in improving the thermal stability of steel?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Formation of dense protective oxide films at high temperatures", "B": "Increasing the dislocation density to enhance creep resistance", "C": "Reducing the thermal expansion coefficient through atomic substitution", "D": "Creating nanoscale precipitates that block grain boundary diffusion" }, "correct_answer": "A", "explanation": "Correct answer A describes the primary mechanism where Cr, Si, and Al form protective oxide layers (Cr2O3, SiO2, Al2O3) that prevent further oxidation. Option B is incorrect because while dislocations affect mechanical properties, they don't directly improve oxidation resistance. Option C is a partial truth but thermal expansion reduction is a secondary effect. Option D describes a valid strengthening mechanism but not the primary thermal stability improvement method for these particular elements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 318, "question": "Explain the meaning of interstitial solid solution", "answer": "An interstitial solid solution is a type of solid solution that retains the crystal structure of the solvent and has very low solubility. The alloying elements are located in the interstitial positions and are themselves very small in size. In terms of properties, it exhibits good toughness and ductility.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释间隙固溶体的含义，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对间隙固溶体这一基本概念的定义、特征和性质的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释间隙固溶体的定义和基本特性，但需要考生理解并记忆多个关键点（如晶体结构保留、低溶解度、间隙位置、尺寸要求以及力学性能）。这比单纯记忆基本定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "An interstitial solid solution is a type of solid solution that retains the crystal structure of the solvent and has very low solubility. The alloying elements are located in the interstitial positions and are themselves very small in size. In terms of properties, it exhibits good toughness and ductility.", "choice_question": "Which of the following best describes an interstitial solid solution?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct description as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A solid solution where solute atoms occupy the interstitial sites of the solvent lattice, maintaining the host crystal structure and requiring solute atomic radii <0.59 times the solvent radius", "B": "A solid solution formed when solute atoms replace solvent atoms in the lattice, creating local distortions while preserving overall crystal symmetry", "C": "A metastable solution where solute atoms cluster in lattice defects, exhibiting short-range ordering and increased hardness", "D": "A solution where solute atoms preferentially segregate to grain boundaries, forming discontinuous precipitates that enhance creep resistance" }, "correct_answer": "A", "explanation": "Option A correctly defines interstitial solid solutions by specifying the critical size ratio (Hume-Rothery rule) and maintaining the host structure. Option B describes substitutional solutions, a common confusion. Option C introduces defect clustering which is incorrect for true interstitial solutions. Option D describes grain boundary segregation, a completely different phenomenon. Advanced AIs might select B due to overgeneralizing 'solid solution' concepts or C due to associating interstitials with defects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1115, "question": "The diffusion of solute atoms always proceeds from regions of high concentration to regions of low concentration.", "answer": "Wrong! The accurate statement is that the diffusion of solute atoms always proceeds from regions of high chemical potential to regions of low chemical potential. Only in this way can the driving force of reactive diffusion be satisfactorily explained.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性，答案明确指出该陈述是错误的并给出正确表述，符合判断题的特征。 | 知识层次: 题目不仅需要理解扩散的基本概念（从高浓度到低浓度），还需要理解化学势在扩散过程中的作用，这涉及到概念的关联和综合分析。虽然题目形式是判断题，但需要更深入的理解才能正确判断陈述的对错。 | 难度: 在选择题型中，该题目属于较高难度。题目不仅要求考生掌握扩散的基本概念（从高浓度到低浓度），还需要理解更深入的化学势概念。正确选项涉及对扩散驱动力的本质理解（化学势梯度而非浓度梯度），并能解释反应扩散的驱动力机制。这需要考生将扩散理论与热力学概念进行综合关联分析，属于中等应用层次的多步概念判断。相比单纯记忆浓度梯度扩散的题目（难度2-3），本题需要更高层次的概念整合能力。", "convertible": true, "correct_option": "Wrong! The accurate statement is that the diffusion of solute atoms always proceeds from regions of high chemical potential to regions of low chemical potential. Only in this way can the driving force of reactive diffusion be satisfactorily explained.", "choice_question": "The diffusion of solute atoms always proceeds from regions of high concentration to regions of low concentration.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all metallic systems, the Hall-Petch relationship predicts that yield strength will increase with decreasing grain size.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the Hall-Petch relationship generally holds for conventional grain sizes, it breaks down at extremely small grain sizes (typically below 10-20 nm) where inverse Hall-Petch behavior may occur due to grain boundary sliding and other mechanisms. This creates a subtle condition trap where the statement appears correct for most cases but fails at nanoscale dimensions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4320, "question": "What is the difference between a phase and a microconstituent?", "answer": "A \"phase\" is a homogeneous portion of the system having uniform physical and chemical characteristics, whereas a \"microconstituent\" is an identifiable element of the microstructure (that may consist of more than one phase).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两个概念的区别，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对\"phase\"和\"microconstituent\"这两个基本概念的定义和区别的理解，属于材料科学中最基础的概念记忆和简单对比范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念的定义，但需要考生理解和区分\"phase\"和\"microconstituent\"这两个相关但不同的概念，并进行比较分析。这比单纯记忆单个定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "A \"phase\" is a homogeneous portion of the system having uniform physical and chemical characteristics, whereas a \"microconstituent\" is an identifiable element of the microstructure (that may consist of more than one phase).", "choice_question": "Which of the following correctly describes the difference between a phase and a microconstituent?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A phase is a homogeneous portion with uniform properties, while a microconstituent is a microstructure feature that may contain multiple phases", "B": "A phase refers to atomic arrangement, while a microconstituent describes grain boundary characteristics", "C": "A phase is defined by its mechanical properties, while a microconstituent is defined by its thermal properties", "D": "A phase must be visible to the naked eye, while a microconstituent requires microscopic observation" }, "correct_answer": "A", "explanation": "The correct answer A precisely distinguishes the fundamental definitions. Option B incorrectly limits phases to atomic arrangement and microconstituents to grain boundaries. Option C wrongly associates phases and microconstituents with specific property categories. Option D introduces an invalid visibility criterion that contradicts actual materials science practice where both may require microscopy.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3589, "question": "The density of potassium, which has the BCC structure and one atom per lattice point, is 0.855 g/cm3. The atomic weight of potassium is 39.09 g/mol. Calculate the lattice parameter.", "answer": "5.3355 x 10^-8 cm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解晶格参数，答案是一个具体的数值结果。 | 知识层次: 题目主要考查基本公式的应用和简单计算，涉及BCC结构的密度计算公式和单位转换，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目要求计算BCC结构的晶格参数，主要涉及密度公式的直接应用和单位换算。虽然需要理解BCC结构的基本概念和密度公式，但解题步骤相对直接，只需套用公式并进行简单计算即可得出答案。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "5.3355 x 10^-8 cm", "choice_question": "The density of potassium, which has the BCC structure and one atom per lattice point, is 0.855 g/cm3. The atomic weight of potassium is 39.09 g/mol. The lattice parameter is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.3355 x 10^-8 cm", "B": "3.774 x 10^-8 cm", "C": "5.3355 x 10^-10 m", "D": "3.774 x 10^-10 m" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the BCC structure formula: a = (2*(atomic weight)/(density*Avogadro's number))^(1/3). Option B is the FCC lattice parameter, exploiting structure confusion. Option C uses correct value but wrong unit (meters instead of cm), targeting unit conversion errors. Option D combines both FCC structure and unit errors, creating a multi-layer trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3243, "question": "In the cubic system, the relationship between the crystal plane (hkl) and the crystal direction [hkl] is A. [hkl]//(hkl) B. [hkl] is perpendicular to (hkl) C. No definite relationship", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项A、B、C中选择正确答案 | 知识层次: 题目考查立方晶系中晶面(hkl)与晶向[hkl]关系的基本概念记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆层次，要求考生理解立方晶系中晶面与晶向的关系。虽然需要一定的晶体学基础知识，但题目仅涉及单一概念的直接应用（垂直关系），无需复杂分析或跨概念比较。相比等级1的直接记忆题稍难，但低于需要深度理解的等级3题目。", "convertible": true, "correct_option": "B. [hkl] is perpendicular to (hkl)", "choice_question": "In the cubic system, the relationship between the crystal plane (hkl) and the crystal direction [hkl] is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed to the question stem.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The [hkl] direction lies within the (hkl) plane", "B": "[hkl] is perpendicular to (hkl)", "C": "The angle between [hkl] and (hkl) depends on the lattice parameter", "D": "No general relationship exists in cubic systems" }, "correct_answer": "B", "explanation": "In cubic crystal systems, the [hkl] direction is always perpendicular to the (hkl) plane due to the high symmetry of the cubic lattice. Option A is a cognitive bias trap that might seem plausible for lower symmetry systems. Option C exploits the intuition that lattice parameters might affect geometric relationships, which is true for non-cubic systems. Option D is a generalization trap that challenges the understanding of cubic symmetry constraints.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4116, "question": "Compared to other ceramic materials, do ceramic-matrix composites have better fracture toughnesses?", "answer": "Ceramic-matrix composites have higher fracture toughnesses than other ceramic materials.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（Ceramic-matrix composites have higher fracture toughnesses than other ceramic materials），答案直接给出了判断结果（是或否），符合判断题的特征。 | 知识层次: 题目考查对陶瓷基复合材料基本性能（断裂韧性）的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求对基础概念进行正误判断，即陶瓷基复合材料是否比其他陶瓷材料具有更高的断裂韧性。题目涉及的知识层次为基础概念记忆，不需要深入理解或复杂分析，因此属于最简单的难度等级。", "convertible": true, "correct_option": "Ceramic-matrix composites have higher fracture toughnesses than other ceramic materials.", "choice_question": "Compared to other ceramic materials, do ceramic-matrix composites have better fracture toughnesses?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic-matrix composites exhibit higher fracture toughness than monolithic ceramics under all loading conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While ceramic-matrix composites generally show improved fracture toughness compared to monolithic ceramics due to their reinforcement mechanisms, this is not universally true for all compositions and loading conditions. The enhancement depends on factors like fiber-matrix bonding, interface characteristics, and loading direction. Some composites may show reduced toughness in certain orientations or under specific stress states.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1860, "question": "In the face-centered cubic close-packed structure of the NaCl unit cell, how many tetrahedral voids are there?", "answer": "There are a total of 8 tetrahedral voids in the NaCl unit cell.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述在NaCl单位晶胞中的四面体空隙数量，答案提供了具体的文字解释和数量，没有涉及计算或选择。 | 知识层次: 题目考查对NaCl晶胞中四面体空隙数量的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要学生对面心立方紧密堆积结构中的空隙类型和数量有清晰的理解。学生需要知道NaCl晶胞的结构特点，并能够准确记忆或推导出四面体空隙的数量。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或比较（等级3）。", "convertible": true, "correct_option": "8", "choice_question": "In the face-centered cubic close-packed structure of the NaCl unit cell, how many tetrahedral voids are there?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible numerical options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "8", "C": "选项B", "D": "选项D" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 263, "question": "Calculate the diffusion coefficient of carbon in γ-Fe (face-centered cubic), given the diffusion coefficient formula as D=0.21exp[-141284/RT] cm²/s, temperature T=800°C (1073K), and gas constant R=8.314 J/(mol·K).", "answer": "Substitute T=1073K into the formula D=0.21exp[-141284/(8.314×1073)] cm²/s, and calculate to obtain D_γ=2.1×10^-8 cm²/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出扩散系数的具体数值。答案展示了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目要求直接套用给定的扩散系数公式进行数值计算，属于基本公式应用和简单计算，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用给定的扩散系数公式，并进行简单的数值代入和计算。不需要理解多个概念或进行复杂的分析，属于单一公式直接计算的难度等级。", "convertible": true, "correct_option": "2.1×10^-8 cm²/s", "choice_question": "Calculate the diffusion coefficient of carbon in γ-Fe (face-centered cubic), given the diffusion coefficient formula as D=0.21exp[-141284/RT] cm²/s, temperature T=800°C (1073K), and gas constant R=8.314 J/(mol·K). The diffusion coefficient is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as the correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.1×10^-8 cm²/s", "B": "1.4×10^-7 cm²/s", "C": "3.7×10^-9 cm²/s", "D": "5.8×10^-6 cm²/s" }, "correct_answer": "A", "explanation": "The correct answer is calculated by substituting the given values into the diffusion coefficient formula D=0.21exp[-141284/(8.314×1073)], which yields 2.1×10^-8 cm²/s. Option B is designed to trap those who incorrectly use the pre-exponential factor as 0.21 cm²/s without the exponential term. Option C exploits the common mistake of using temperature in Celsius instead of Kelvin. Option D is based on the diffusion coefficient for α-Fe (BCC) at the same temperature, exploiting confusion between FCC and BCC structures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 894, "question": "Term explanation: phase diagram", "answer": "A graphical representation describing the conditions for phase equilibrium or the coexistence relationships of phases; it can also be referred to as the geometric trajectory of thermodynamic parameters at equilibrium.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对术语进行解释，答案是一段文字描述，属于简答题类型 | 知识层次: 题目考查对相图这一基础概念的定义和基本理解，属于记忆性知识范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释\"phase diagram\"这一基础概念，但正确选项提供了较为详细的描述，包括图形表示、相平衡条件以及热力学参数轨迹等。这需要学生对相图有基本的理解和记忆，而不仅仅是简单的定义复述。因此，该题目在选择题型中属于概念解释和描述级别(等级2)。", "convertible": true, "correct_option": "A graphical representation describing the conditions for phase equilibrium or the coexistence relationships of phases; it can also be referred to as the geometric trajectory of thermodynamic parameters at equilibrium.", "choice_question": "Which of the following best defines a phase diagram?", "conversion_reason": "The answer is a standard definition of a term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A graphical representation describing the conditions for phase equilibrium or the coexistence relationships of phases; it can also be referred to as the geometric trajectory of thermodynamic parameters at equilibrium.", "B": "A plot showing the mechanical properties of materials as a function of temperature, used to predict material behavior under stress.", "C": "A diagram illustrating the atomic arrangement and crystallographic planes in a material, essential for understanding diffraction patterns.", "D": "A chart mapping the electrical conductivity of materials against their thermal conductivity, used to identify thermoelectric materials." }, "correct_answer": "A", "explanation": "The correct answer is A because a phase diagram specifically represents phase equilibrium conditions and thermodynamic parameters at equilibrium. Option B is incorrect as it describes mechanical property charts, not phase diagrams. Option C is a crystallographic description, not a phase diagram. Option D describes a property correlation chart, unrelated to phase equilibrium. These distractors exploit common material science concept confusions and 'first impression' errors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3545, "question": "The twinning plane of a face-centered cubic crystal is ( ) A.(112} B.{110} C.111", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查面心立方晶体孪晶面的基本概念记忆，属于对晶体学基础知识的直接回忆，不需要复杂的分析或计算。 | 难度: 该题目属于基础概念记忆，仅需直接回忆面心立方晶体的孪晶面是{111}即可作答，无需理解或辨析其他选项。在选择题型中属于最简单的直接记忆类题目。", "convertible": true, "correct_option": "C", "choice_question": "The twinning plane of a face-centered cubic crystal is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress is independent of crystal orientation", "B": "The Schmid factor reaches its maximum value at 45° orientation", "C": "Dislocation motion is easiest along <110> directions in FCC crystals", "D": "The Peierls-Nabarro stress is lowest for screw dislocations" }, "correct_answer": "A", "explanation": "Correct answer A is counterintuitive but fundamental - CRSS is indeed a material constant independent of orientation. Option B exploits the common misconception that maximum Schmid factor occurs at 45° (actually at 54.7°). Option C plays on the intuitive but incorrect assumption about slip directions. Option D uses the subtle difference between edge and screw dislocations' Peierls stress that often confuses even experts.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1577, "question": "6．Critical deformation", "answer": "The minimum pre-deformation required to cause recrystallization in a metal material when heated above the recrystallization temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Critical deformation\"进行定义和解释，需要文字描述和论述，而不是选择、判断或计算。答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查的是\"Critical deformation\"这一专业术语的基本定义，属于金属材料再结晶过程中的基础概念记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆，但要求考生不仅知道\"Critical deformation\"这个术语，还需要理解其具体定义和应用场景（即金属材料在再结晶温度以上加热时引发再结晶所需的最小预变形量）。这比单纯识别术语名称（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "The minimum pre-deformation required to cause recrystallization in a metal material when heated above the recrystallization temperature.", "choice_question": "What is Critical deformation?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct definition among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The minimum pre-deformation required to cause recrystallization when heated above the recrystallization temperature", "B": "The maximum strain a material can withstand before fracture at room temperature", "C": "The deformation threshold where dislocation density reaches saturation point", "D": "The critical strain required to initiate dynamic recrystallization during hot working" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines critical deformation in the context of static recrystallization. Option B exploits cognitive bias by confusing it with fracture strain. Option C uses professional intuition trap by referencing dislocation saturation, a related but different concept. Option D is a multi-level trap that correctly describes dynamic recrystallization but is irrelevant to the static recrystallization context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4258, "question": "A cylindrical rod of copper (E=110g P a, 16 × 10^{6} psi) having a yield strength of 240 MPa(35,000 psi) is to be subjected to a load of 6660N\\left(1500 lb p\\right). If the length of the rod is 380 mm(15.0 in.), what must be the diameter to allow an elongation of 0.50 mm(0.020 in.) ?", "answer": "the diameter must be 7.65mm (0.30 in).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定铜棒的直径，答案是一个具体的数值结果（7.65mm），解答过程需要运用材料力学中的弹性变形公式进行计算。 | 知识层次: 题目需要进行多步计算，包括应用胡克定律计算应力、应变关系，以及几何关系计算直径，涉及概念关联和综合分析。虽然不涉及复杂的推理分析或机理解释，但需要一定的思维深度和计算步骤。 | 难度: 在选择题中属于中等偏上难度，需要综合运用弹性模量、应力应变关系和几何变形公式进行多步计算。题目涉及单位换算、公式变形和综合分析能力，但作为选择题可以通过选项验证简化部分计算步骤。", "convertible": true, "correct_option": "7.65mm (0.30 in)", "choice_question": "A cylindrical rod of copper (E=110g P a, 16 × 10^{6} psi) having a yield strength of 240 MPa(35,000 psi) is to be subjected to a load of 6660N(1500 lb p). If the length of the rod is 380 mm(15.0 in.), what must be the diameter to allow an elongation of 0.50 mm(0.020 in.)?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.65 mm (0.30 in)", "B": "5.41 mm (0.21 in)", "C": "9.87 mm (0.39 in)", "D": "6.22 mm (0.24 in)" }, "correct_answer": "A", "explanation": "正确答案A是通过弹性变形公式ΔL=FL/(AE)计算得出，其中A=πd²/4。干扰项B利用常见错误，混淆了应力与应变关系，直接使用σ=F/A计算而忽略伸长量要求。干扰项C设计为表面合理但实际过大的直径，利用了材料科学中'安全系数'的直觉陷阱。干扰项D基于错误假设，将屈服强度直接作为设计标准而非伸长量要求，是典型的专业直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2695, "question": "Calculate the theoretical density of α-Fe (given a=0.286nm for α-Fe, Ar(Fe)=55.85, NA=6.023×10²³)", "answer": "ρtheoretical=2×Ar(Fe)/(a³×NA)=2×55.85/((2.86×10⁻⁸)³×6.023×10²³)=7.9276(g/cm³)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的参数（晶格常数a、原子量Ar、阿伏伽德罗常数NA）和公式（理论密度计算公式）进行数值计算，最终得出具体的密度值7.9276g/cm³，符合计算题的特征。 | 知识层次: 题目要求应用基本公式进行简单计算，涉及晶体结构参数和密度的直接套用，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要套用密度计算公式，但步骤较为直接，仅涉及单一公式的代入和简单数值计算，无需复杂的推导或多步骤分析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "7.9276 g/cm³", "choice_question": "Calculate the theoretical density of α-Fe (given a=0.286nm for α-Fe, Ar(Fe)=55.85, NA=6.023×10²³). The theoretical density is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.9276 g/cm³", "B": "7.8740 g/cm³", "C": "8.9123 g/cm³", "D": "7.1234 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer is A (7.9276 g/cm³) calculated using the BCC unit cell formula: density = (2 × Ar(Fe))/(a³ × NA). Option B (7.8740 g/cm³) is the experimental density of α-Fe at room temperature, exploiting the common confusion between theoretical and experimental values. Option C (8.9123 g/cm³) mimics the FCC structure density, targeting those who misremember the crystal structure. Option D (7.1234 g/cm³) uses incorrect unit conversion (nm to cm) to catch calculation errors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 797, "question": "What factors influence the formation of amorphous metals? Why", "answer": "Viscosity of liquid metal: the higher the viscosity, the more difficult the atomic diffusion, making it easier to retain the liquid metal structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释影响非晶金属形成的因素，答案提供了文字解释和论述，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目要求分析非晶金属形成的因素，并解释原因，涉及多因素的综合分析和机理解释，需要深入理解原子扩散、粘度等概念及其相互作用，属于复杂分析层次。 | 难度: 在选择题型中，该题目要求考生不仅理解基本概念（如粘度、原子扩散），还需要综合运用这些知识进行复杂现象的全面分析（粘度如何影响非晶态金属的形成）。正确选项涉及机理深度解释（粘度与原子扩散的关系及其对金属结构的影响），这超出了简单记忆或基础理解的范畴，属于选择题型中的高难度水平。", "convertible": true, "correct_option": "Viscosity of liquid metal: the higher the viscosity, the more difficult the atomic diffusion, making it easier to retain the liquid metal structure.", "choice_question": "Which of the following factors influences the formation of amorphous metals?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Viscosity of liquid metal: the higher the viscosity, the more difficult the atomic diffusion, making it easier to retain the liquid metal structure", "B": "Elastic modulus of the solid phase: higher modulus promotes faster cooling rates required for amorphous formation", "C": "Thermal conductivity: lower conductivity increases critical cooling rate by slowing heat dissipation", "D": "Crystal structure of the primary phase: FCC metals have higher glass-forming ability due to their close-packed planes" }, "correct_answer": "A", "explanation": "The correct answer is A because high viscosity impedes atomic rearrangement necessary for crystallization. Option B is a cognitive bias trap - while elastic modulus relates to mechanical properties, it doesn't directly affect glass formation kinetics. Option C reverses causality - lower conductivity actually decreases critical cooling rate. Option D exploits material analogy fallacy - while FCC metals can form glasses, their structure alone doesn't determine glass-forming ability which depends on kinetic factors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1507, "question": "What is the reason for the change in properties of ferrite compared to pure iron", "answer": "Solid solution", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释铁素体与纯铁性能变化的原因，需要文字论述而非选择或判断。答案\"Solid solution\"是一个简短的解释性回答，符合简答题的特征。 | 知识层次: 题目要求解释铁素体与纯铁性能差异的原因，涉及固溶体概念的应用和性能变化的综合分析，需要理解固溶体对材料性能的影响机制，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解固溶体的概念及其对铁素体性能的影响，并进行综合分析。题目要求考生将纯铁与铁素体的性能变化原因联系起来，涉及中等应用层次的知识，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "Solid solution", "choice_question": "What is the reason for the change in properties of ferrite compared to pure iron?", "conversion_reason": "The answer is a standard term (Solid solution), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening from carbon interstitial atoms", "B": "Grain boundary refinement due to carbon segregation", "C": "Dislocation pinning by carbide precipitates", "D": "Phase transformation induced lattice distortion" }, "correct_answer": "A", "explanation": "The correct answer is A because ferrite is specifically defined as the interstitial solid solution of carbon in BCC iron. Option B is incorrect because carbon segregation occurs primarily at grain boundaries but doesn't fundamentally change the bulk properties. Option C is a trap as it describes pearlite or tempered martensite, not pure ferrite. Option D is misleading as it describes martensitic transformation, not the equilibrium ferrite phase.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3270, "question": "What factors constitute the resistance to phase transformation?", "answer": "The resistance to phase transformation consists of strain energy and interface energy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释影响相变阻力的因素，答案提供了文字解释和论述，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目考查对相变阻力构成因素的基本概念记忆和理解，涉及的是定义和基本原理等记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目直接询问相变阻力的构成因素，正确选项明确给出了两个基本概念（应变能和界面能），不需要进行额外的解释或复杂分析。这属于最基础的概念记忆题，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "strain energy and interface energy", "choice_question": "What factors constitute the resistance to phase transformation?", "conversion_reason": "The answer is a standard term or concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "strain energy and interface energy", "B": "elastic modulus and stacking fault energy", "C": "activation energy and thermal conductivity", "D": "grain boundary energy and dislocation density" }, "correct_answer": "A", "explanation": "The correct answer is A because strain energy (from lattice distortion) and interface energy (between parent and new phases) are the fundamental barriers to phase transformation. Option B uses elastic modulus (a bulk property) and stacking fault energy (specific to dislocations) which are irrelevant to transformation kinetics. Option C combines activation energy (correct concept but too general) with thermal conductivity (irrelevant transport property). Option D mixes grain boundary energy (only relevant for polycrystals) with dislocation density (affects nucleation but not the intrinsic energy barrier).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 210, "question": "Many properties of clay are related to the types of adsorbed cations. Indicate the variation pattern of slurry fluidity for clay adsorbed with the following different cations (use arrows to denote: small—large) H+ Al3+ Ba2+ Sr2+ Ca2+ Mg2+ NH4+ K+ Na+ Li+", "answer": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求用箭头表示不同阳离子吸附下粘土浆体流动性的变化规律，答案是一个排序结果，需要解释和论述不同阳离子的影响，属于简答题类型。 | 知识层次: 题目要求考生理解不同阳离子对粘土浆体流动性的影响，并能够根据离子特性（如电荷、半径等）进行排序。这需要考生不仅记住阳离子的基本性质，还要能够应用这些知识来分析其对粘土性质的影响，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合理解粘土吸附阳离子的性质及其对浆体流动性的影响规律。题目要求考生掌握不同阳离子的吸附能力及其对粘土浆体流动性的影响趋势，涉及多个概念的综合分析和比较。正确选项的排列顺序需要基于对阳离子电荷、半径及其与粘土表面相互作用的理解，属于多角度分析论述的层次。", "convertible": true, "correct_option": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "choice_question": "Which of the following correctly represents the variation pattern of slurry fluidity for clay adsorbed with the given cations (from small to large)?", "conversion_reason": "The original short answer question asks for a specific ordered sequence of cations based on slurry fluidity, which can be directly converted into a multiple-choice question by presenting the correct sequence as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "B": "Al3+ < H+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "C": "H+ < Al3+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < NH4+ < K+ < Na+ < Li+", "D": "Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+ < H+" }, "correct_answer": "A", "explanation": "The correct order (A) follows the lyotropic series based on cation hydration energy and ionic potential. H+ has the strongest adsorption due to its small size and high charge density, while Li+ has the weakest. Option B incorrectly places Al3+ before H+, exploiting the common misconception that higher charge always means stronger adsorption. Option C reverses the divalent cation order, playing on the intuition that smaller ions should come first. Option D is a complete inversion, targeting the tendency to assume direct correlation between ion size and adsorption strength without considering hydration effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1477, "question": "Explain the characteristics of grain growth process during heating of cold-deformed metals", "answer": "Grain growth. It causes some property changes, such as decreases in strength, plasticity, and toughness. Along with grain growth, other structural changes also occur, such as recrystallization texture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释冷变形金属加热过程中晶粒生长的特性，需要文字解释和论述，答案也提供了详细的文字描述，符合简答题的特征。 | 知识层次: 题目要求解释冷变形金属加热过程中的晶粒生长特性，涉及晶粒生长对性能的影响以及其他结构变化（如再结晶织构）。这需要将多个概念（晶粒生长、性能变化、结构变化）关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解冷变形金属加热过程中的晶粒生长特性及其对性能的影响，并关联其他结构变化如再结晶织构。虽然不涉及多步计算，但需要对多个概念进行综合分析和说明。", "convertible": true, "correct_option": "Grain growth. It causes some property changes, such as decreases in strength, plasticity, and toughness. Along with grain growth, other structural changes also occur, such as recrystallization texture.", "choice_question": "Which of the following best describes the characteristics of grain growth process during heating of cold-deformed metals?", "conversion_reason": "The answer is a standard description of the grain growth process, which can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain growth causes decreases in strength and toughness, while recrystallization texture develops simultaneously", "B": "Grain growth increases dislocation density, leading to simultaneous improvements in strength and ductility", "C": "Grain growth eliminates all texture components while significantly increasing yield strength", "D": "Grain growth occurs before recrystallization, resulting in a temporary increase in hardness" }, "correct_answer": "A", "explanation": "The correct answer is A because grain growth during heating of cold-deformed metals indeed leads to decreases in strength and toughness due to reduced grain boundary area, while recrystallization textures develop as part of the microstructural evolution. Option B is wrong but tempting because it incorrectly associates grain growth with dislocation density increase (actually decreases) and implies simultaneous strength-ductility improvement (impossible trade-off). Option C is a multi-layer trap combining the false elimination of texture with incorrect strength behavior. Option D reverses the actual sequence (recrystallization precedes grain growth) and wrongly suggests hardness increase.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4346, "question": "Compute the mass fraction of eutectoid ferrite in an iron-carbon alloy that contains 0.43 wt% C.", "answer": "the mass fraction of eutectoid ferrite in the iron-carbon alloy is 0.493.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算共析铁素体的质量分数），答案是一个具体的数值结果（0.493），解答过程需要应用材料科学中的相图知识和计算公式。 | 知识层次: 题目需要应用铁碳相图的知识，进行多步计算来确定共析铁素体的质量分数。这涉及到理解相图中不同区域的相组成，以及如何利用杠杆法则进行计算。虽然计算本身不复杂，但需要正确理解相图和相组成的概念，并进行适当的公式应用和数值计算。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图、共析反应等概念，并进行多步计算。题目要求计算共析铁素体的质量分数，涉及相组成和杠杆定律的应用，属于综合性计算问题。虽然题目给出了正确选项，但解题过程需要较强的概念关联和综合分析能力。", "convertible": true, "correct_option": "0.493", "choice_question": "What is the mass fraction of eutectoid ferrite in an iron-carbon alloy that contains 0.43 wt% C?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.493", "B": "0.567", "C": "0.417", "D": "0.602" }, "correct_answer": "A", "explanation": "The correct answer is A (0.493) as it's calculated using the lever rule at the eutectoid composition (0.76 wt% C). Option B (0.567) is designed to exploit confusion between hypoeutectoid and hypereutectoid calculations. Option C (0.417) mimics a common error of using the alloy composition directly. Option D (0.602) targets those who might incorrectly consider proeutectoid ferrite in the calculation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4770, "question": "What is the third criterion upon which factors of safety are based?", "answer": "The third criterion is accuracy of measurement of mechanical forces and/or material properties.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释第三个安全系数的标准，答案需要文字论述而非选择、判断或计算 | 知识层次: 题目考查对安全系数基础标准的记忆和理解，属于基本概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要记忆安全系数的第三个标准，但这是基础概念记忆层面的知识，不需要复杂的分析或推理。题目仅要求考生回忆并识别正确的定义，属于\"概念解释和描述\"层次，比简单定义稍复杂但远未达到复杂概念体系阐述的程度。", "convertible": true, "correct_option": "The third criterion is accuracy of measurement of mechanical forces and/or material properties.", "choice_question": "What is the third criterion upon which factors of safety are based?", "conversion_reason": "The answer is a standard and specific statement, making it suitable for conversion into a multiple-choice question format where this statement can be the correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Accuracy of measurement of mechanical forces and/or material properties", "B": "Statistical variability of applied loads and material strengths", "C": "Consequences of failure in terms of human safety and economic loss", "D": "Temperature dependence of material properties under service conditions" }, "correct_answer": "A", "explanation": "The correct answer is A because it directly addresses the third criterion related to measurement accuracy in safety factor determination. Option B is a primary criterion (first or second) that exploits the AI's tendency to prioritize statistical considerations. Option C is another primary criterion that plays on the AI's bias toward human safety concerns. Option D introduces a plausible but irrelevant factor that could mislead models into considering environmental effects instead of fundamental safety criteria.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4694, "question": "Calculate the number of vacancies per cubic meter in gold (\\mathrm{Au}) at 900^{\\circ} C. The energy for vacancy formation is 0.98 \\mathrm{eV} / atom. Furthermore, the density and atomic weight for Au are 18.63 \\mathrm{g} / {cm}^{3} (at 900^{\\circ} C ) and 196.9g / mol, respectively.", "answer": "the number of vacancies per cubic meter in gold at 900^{\\circ} C is 3.52 × 10^{24}{m}^{-3}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算，涉及公式应用（如计算空位浓度），答案是一个具体的数值结果（3.52 × 10^{24}{m}^{-3}），符合计算题的特征。 | 知识层次: 题目需要多步计算和概念关联，包括应用阿伏伽德罗常数、密度和原子重量计算原子数，以及使用玻尔兹曼方程计算空位浓度。虽然不涉及复杂的推理分析或创新应用，但需要综合运用多个知识点进行中等难度的计算。 | 难度: 在选择题中属于中等偏上难度，需要综合运用多个概念和公式进行计算。题目涉及的知识点包括空位浓度计算、能量单位转换、密度和原子量的应用等。解题步骤包括：1) 计算金的原子密度；2) 利用空位形成能和温度计算空位浓度；3) 进行单位转换和指数运算。虽然题目提供了所有必要参数，但需要考生熟练掌握相关公式并能正确进行多步计算，在选择题型中属于需要较强综合分析能力的题目。", "convertible": true, "correct_option": "3.52 × 10^{24} m^{-3}", "choice_question": "Calculate the number of vacancies per cubic meter in gold (Au) at 900°C, given the energy for vacancy formation is 0.98 eV/atom, the density is 18.63 g/cm³, and the atomic weight is 196.9 g/mol. The correct answer is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.52 × 10^{24} m^{-3}", "B": "7.21 × 10^{22} m^{-3} (using Boltzmann constant in J/mol·K instead of eV/K)", "C": "1.84 × 10^{25} m^{-3} (neglecting temperature conversion from °C to K)", "D": "5.63 × 10^{23} m^{-3} (using room temperature density instead of 900°C value)" }, "correct_answer": "A", "explanation": "The correct answer A uses the proper Arrhenius equation with all unit conversions: n = N·exp(-Qv/kT), where N is atomic density calculated from given parameters (18.63 g/cm³ → 5.69×10^{28} atoms/m³), Qv=0.98 eV, and T=1173 K. Option B traps those who confuse energy units by using R instead of k. Option C exploits temperature unit oversight. Option D uses an incorrect density value, creating a plausible but wrong vacancy concentration.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1933, "question": "How does the thermal motion of atoms affect diffusion?", "answer": "The enhancement of thermal motion will increase the jump distance, jump probability, and jump frequency of atoms, thereby increasing the diffusion coefficient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释热运动如何影响扩散，答案提供了详细的文字解释和论述，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目需要理解热运动与扩散系数之间的关系，涉及原子跳跃距离、概率和频率等概念的关联，并进行综合分析解释扩散系数的变化。这超出了基础概念的记忆，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解热运动与扩散系数之间的多因素关联（跳跃距离、概率、频率），并能综合分析这些因素如何共同影响扩散行为。虽然不涉及计算，但要求对物理机制有较深的概念掌握和逻辑推导能力。", "convertible": true, "correct_option": "The enhancement of thermal motion will increase the jump distance, jump probability, and jump frequency of atoms, thereby increasing the diffusion coefficient.", "choice_question": "How does the thermal motion of atoms affect diffusion?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be kept as is or slightly rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The enhancement of thermal motion will increase the jump distance, jump probability, and jump frequency of atoms, thereby increasing the diffusion coefficient", "B": "Thermal motion primarily affects the equilibrium vacancy concentration but has negligible impact on atomic jump frequency", "C": "Increased thermal energy reduces the activation energy barrier for diffusion, making atomic jumps less dependent on temperature", "D": "Higher thermal motion causes lattice contraction which decreases the available diffusion pathways" }, "correct_answer": "A", "explanation": "The correct answer A captures the comprehensive effect of thermal motion on all three key diffusion parameters. Option B is a partial truth trap that correctly identifies vacancy concentration but wrongly minimizes jump frequency effects. Option C reverses the temperature dependence relationship, exploiting common misconceptions about activation energy. Option D introduces a plausible-sounding but physically incorrect lattice contraction mechanism, targeting confusion between thermal expansion and atomic vibration amplitudes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3979, "question": "During the recovery of a cold-worked material, is the thermal conductivity recovered to its precold-worked state?", "answer": "The thermal conductivity is recovered to its precold-worked state.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（即热导率是否恢复到冷加工前的状态），答案直接给出了对陈述的判断（是或否）。 | 知识层次: 题目考查对冷加工材料恢复过程中热导率变化的基础概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 该题目属于基础概念记忆类型，仅需判断热导率在冷加工材料恢复过程中是否恢复到原始状态。题目直接给出了正确选项，无需复杂推理或概念比较，符合选择题型中最简单的正误判断难度等级。", "convertible": true, "correct_option": "The thermal conductivity is recovered to its precold-worked state.", "choice_question": "During the recovery of a cold-worked material, is the thermal conductivity recovered to its precold-worked state?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All cold-worked materials will completely regain their original thermal conductivity after full recrystallization annealing.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While thermal conductivity generally improves during recovery and recrystallization, complete restoration to the precold-worked state depends on multiple factors including material purity, annealing conditions, and the extent of prior deformation. Impurities and incomplete recrystallization can prevent full recovery of thermal conductivity. The absolute term 'all' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4724, "question": "Germanium (Ge) forms a substitutional solid solution with silicon (Si). Compute the weight percent of germanium that must be added to silicon to yield an alloy that contains 2.43 × 10^{21} Ge atoms per cubic centimeter. The densities of pure \\mathrm{Ge} and \\mathrm{Si} are 5.32 and 2.33g / {cm}^{3}, respectively.", "answer": "11.7 wt%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解需要添加的锗的重量百分比，答案是一个具体的数值结果（11.7 wt%），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括原子密度计算、质量分数转换等，并需要理解固溶体的基本概念和密度与原子数的关系。虽然不涉及复杂的推理分析，但需要综合应用多个知识点进行计算。 | 难度: 在选择题中属于中等偏上难度，需要理解固溶体、原子浓度、密度和重量百分比等多个概念，并进行多步计算和综合分析。虽然题目提供了正确选项，但解题过程涉及单位转换、原子量计算和密度应用，步骤较为复杂，属于综合性计算问题。", "convertible": true, "correct_option": "11.7 wt%", "choice_question": "Germanium (Ge) forms a substitutional solid solution with silicon (Si). What weight percent of germanium must be added to silicon to yield an alloy that contains 2.43 × 10^{21} Ge atoms per cubic centimeter, given the densities of pure Ge and Si are 5.32 and 2.33 g/cm³, respectively?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "11.7 wt%", "B": "8.3 wt%", "C": "15.2 wt%", "D": "6.9 wt%" }, "correct_answer": "A", "explanation": "正确答案A(11.7 wt%)通过精确计算得出：首先计算每立方厘米Ge原子数对应的质量，然后考虑Si的密度计算合金总质量，最后得出重量百分比。干扰项B(8.3 wt%)利用了忽略密度差异的常见错误；C(15.2 wt%)基于错误的原子质量比计算；D(6.9 wt%)则混淆了原子浓度与重量百分比的概念。这些干扰项专门针对AI可能出现的计算步骤遗漏或概念混淆问题。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 902, "question": "Briefly describe the changes in mechanical properties of deformed metals during annealing", "answer": "Hardness and strength decrease, elongation increases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述变形金属在退火过程中机械性能的变化，答案以文字解释的形式给出，符合简答题的特征。 | 知识层次: 题目考查对退火过程中金属机械性能变化的基本概念记忆和理解，属于基础知识的直接应用，不需要复杂的分析或综合。 | 难度: 在选择题型中，该题目仅要求考生记忆并选择描述退火过程中金属机械性能变化的基本定义。题目涉及的知识点非常基础，属于金属材料科学中最基本的记忆性内容，不需要任何解释或分析步骤。正确选项直接给出了硬度、强度和延伸率变化的简单描述，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Hardness and strength decrease, elongation increases.", "choice_question": "Which of the following describes the changes in mechanical properties of deformed metals during annealing?", "conversion_reason": "The answer is a standard description of the changes in mechanical properties during annealing, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hardness and strength decrease, elongation increases", "B": "Hardness increases, strength decreases, elongation remains constant", "C": "Hardness decreases, strength increases, elongation decreases", "D": "All mechanical properties improve simultaneously" }, "correct_answer": "A", "explanation": "During annealing, deformed metals undergo recovery and recrystallization, leading to reduced dislocation density which decreases hardness and strength while increasing ductility (elongation). Option B incorrectly suggests hardness increases due to confusion with work hardening. Option C reverses the strength-ductility relationship, a common misconception. Option D violates the fundamental trade-off between strength and ductility in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 337, "question": "What are the main characteristics of allotriomorphic transformation?", "answer": "Allotriomorphic transformation is primarily a phase change that occurs in pure components in the solid state, with no compositional changes, controlled by short-range diffusion processes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释allotriomorphic transformation的主要特征，答案提供了详细的文字解释和论述，符合简答题的特点。 | 知识层次: 题目考查对allotriomorphic transformation这一基本概念的定义和主要特征的理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆（定义、分类、基本原理等），但需要学生对\"allotriomorphic transformation\"这一专业术语有准确的理解，并能区分其与其它相变类型的特征差异。题目正确选项包含了多个关键特征描述（纯组分、固态相变、无成分变化、短程扩散控制），要求学生对这些概念有较全面的掌握，而不仅仅是简单记忆定义。", "convertible": true, "correct_option": "Allotriomorphic transformation is primarily a phase change that occurs in pure components in the solid state, with no compositional changes, controlled by short-range diffusion processes.", "choice_question": "Which of the following best describes the main characteristics of allotriomorphic transformation?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as one of the options and asking for the best description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Allotriomorphic transformation is primarily a phase change that occurs in pure components in the solid state, with no compositional changes, controlled by short-range diffusion processes", "B": "Allotriomorphic transformation involves long-range diffusion and significant compositional changes, typically observed in alloy systems", "C": "Allotriomorphic transformation is a surface phenomenon requiring liquid phase participation, commonly seen in rapid solidification processes", "D": "Allotriomorphic transformation is governed by dislocation motion and results in anisotropic grain growth patterns" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes allotriomorphic transformation as a solid-state phase change in pure components without compositional changes. Option B incorrectly introduces long-range diffusion and compositional changes, which are characteristics of diffusional transformations. Option C falsely associates it with liquid phase and rapid solidification, creating a surface phenomenon misconception. Option D misleadingly connects it to dislocation mechanisms, which are more relevant to mechanical deformation than phase transformations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1778, "question": "There is a green body with an initial particle size of 5μm. After sintering for 2h, x/r=0.1. If sintering continues until x/r=0.2 (without considering grain growth), what is the required sintering time when the material transport is dominated by evaporation-condensation?", "answer": "16h", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要基于给定的初始条件和公式（x/r与时间的关系）进行数值计算，最终得出一个具体的数值答案（16h）。解答过程涉及材料科学中的烧结动力学和蒸发-凝聚机制的应用，属于典型的计算题特征。 | 知识层次: 题目涉及多步计算和概念关联，需要理解蒸发-凝聚机制下的烧结动力学方程，并应用x/r与时间的关系进行推导和计算。虽然不涉及复杂的综合分析或机理解释，但需要一定的公式应用和数值计算能力。 | 难度: 在选择题中属于中等难度，需要理解烧结动力学中的蒸发-凝聚机制，并应用相关公式进行多步计算。题目要求从初始条件推导出新的烧结时间，涉及对x/r比例与时间关系的理解（通常为立方关系），需要进行两次计算步骤（先求比例系数再求新时间）。虽然计算本身不复杂，但需要正确关联材料科学原理和数学关系，属于典型的综合性计算问题。", "convertible": true, "correct_option": "16h", "choice_question": "There is a green body with an initial particle size of 5μm. After sintering for 2h, x/r=0.1. If sintering continues until x/r=0.2 (without considering grain growth), what is the required sintering time when the material transport is dominated by evaporation-condensation?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "16h", "B": "8h", "C": "4h", "D": "32h" }, "correct_answer": "A", "explanation": "The correct answer is A (16h) because for evaporation-condensation dominated sintering, the neck growth follows x/r ∝ t^(1/3). When x/r doubles from 0.1 to 0.2, the required time increases by a factor of 8 (2^3), hence 2h × 8 = 16h. Option B (8h) is a common mistake from linear extrapolation. Option C (4h) results from incorrectly assuming square root dependence. Option D (32h) comes from misapplying the exponent as 1/5 instead of 1/3.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4926, "question": "The formula for samarium iron garnet (Sm3Fe5O12) may be written in the form Sm3^aFe2^cFe3^dO12, where the superscripts a, c, and d represent different sites on which the Sm^3+ and Fe^3+ ions are located. The spin magnetic moments for the Sm^3+ and Fe^3+ ions positioned in a and c sites are oriented parallel to one another and antiparallel to the Fe^3+ ions in d sites. Compute the number of Bohr magnetons associated with each Sm^3+ ion, given the following information: (1) each unit cell consists of eight formula (Sm3Fe5O12) units; (2) the unit cell is cubic with an edge length of 1.2529 nm; (3) the saturation magnetization for this material is 1.35 × 10^5 A/m; and (4) there are 5 Bohr magnetons associated with each Fe^3+ ion.", "answer": "2.86 bm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的信息和公式进行计算，最终得出一个具体的数值结果（2.86 bm）。解答过程需要应用材料科学中的磁学知识和数学计算，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及多个概念的综合应用，包括磁矩计算、单位晶胞分析、饱和磁化强度与磁矩的关系等。虽然不涉及复杂的推理分析或创新设计，但需要较强的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念并进行多步计算和综合分析。题目涉及材料科学中的磁学性质计算，需要掌握单位晶胞、饱和磁化强度、玻尔磁子等概念，并能将这些概念关联起来进行综合计算。虽然题目提供了所有必要的信息，但解题步骤较为复杂，需要较高的概念理解和计算能力。", "convertible": true, "correct_option": "2.86 bm", "choice_question": "The formula for samarium iron garnet (Sm3Fe5O12) may be written in the form Sm3^aFe2^cFe3^dO12, where the superscripts a, c, and d represent different sites on which the Sm^3+ and Fe^3+ ions are located. The spin magnetic moments for the Sm^3+ and Fe^3+ ions positioned in a and c sites are oriented parallel to one another and antiparallel to the Fe^3+ ions in d sites. Compute the number of Bohr magnetons associated with each Sm^3+ ion, given the following information: (1) each unit cell consists of eight formula (Sm3Fe5O12) units; (2) the unit cell is cubic with an edge length of 1.2529 nm; (3) the saturation magnetization for this material is 1.35 × 10^5 A/m; and (4) there are 5 Bohr magnetons associated with each Fe^3+ ion.", "conversion_reason": "The question is a calculation problem with a specific numerical answer (2.86 bm), which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.86 bm", "B": "5.72 bm", "C": "0.72 bm", "D": "4.28 bm" }, "correct_answer": "A", "explanation": "The correct answer is A (2.86 bm) because it accounts for the antiparallel alignment of moments and proper unit cell calculations. Option B (5.72 bm) doubles the correct value, exploiting a common calculation error when dealing with unit cell multiples. Option C (0.72 bm) uses incorrect spin moment assumptions for Sm3+ ions. Option D (4.28 bm) combines partial contributions from Fe3+ ions incorrectly, creating a plausible but wrong intermediate value.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2284, "question": "Predict the strength σLu of a β-SiC whisker-reinforced composite with a volume fraction φf=0.1, given the average fiber stress σf=5320MPa and the matrix yield strength σy=76MPa.", "answer": "For the β-SiC whisker composite, the strength σLu = σf × φf + σy × (1 - φf) = 5320 × 0.1 + 76 × 0.9 = 700MPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和数值进行具体计算，最终得出一个数值结果。解答过程涉及公式应用和数值运算，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，即使用给定的公式和数值进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算，即σLu = σf × φf + σy × (1 - φf)。解题步骤简单，无需复杂的分析或组合多个公式，属于最基础的难度等级。", "convertible": true, "correct_option": "700MPa", "choice_question": "Predict the strength σLu of a β-SiC whisker-reinforced composite with a volume fraction φf=0.1, given the average fiber stress σf=5320MPa and the matrix yield strength σy=76MPa.", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option is clearly identifiable.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "700MPa", "B": "532MPa", "C": "539.6MPa", "D": "76MPa" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the rule of mixtures for composite strength: σLu = φfσf + (1-φf)σy = 0.1*5320 + 0.9*76 = 700MPa. Option B (532MPa) is a cognitive bias trap that only considers φfσf. Option C (539.6MPa) is a professional intuition trap that incorrectly uses the harmonic mean approach. Option D (76MPa) is a verification trap that only considers the matrix strength.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1391, "question": "Unit dislocation", "answer": "A unit dislocation is a dislocation whose Burgers vector equals a lattice vector.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Unit dislocation\"进行文字解释和论述，答案是一个定义性的陈述，符合简答题的特征 | 知识层次: 题目考查对位错基本概念的记忆和理解，特别是单位位错的定义及其Burgers矢量的特征。这属于材料科学中晶体缺陷的基础知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅考察对\"unit dislocation\"这一基础概念的记忆，即其Burgers vector等于晶格矢量的定义。题目不涉及任何解释、比较或分析过程，属于最基础的定义简答类型，因此难度等级为1。", "convertible": true, "correct_option": "A unit dislocation is a dislocation whose Burgers vector equals a lattice vector.", "choice_question": "Which of the following correctly describes a unit dislocation?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A dislocation whose Burgers vector equals a lattice vector", "B": "A dislocation with the smallest possible Burgers vector magnitude in a crystal", "C": "A dislocation that conserves the total number of atomic planes", "D": "A perfect dislocation that can dissociate into partial dislocations" }, "correct_answer": "A", "explanation": "The correct answer is A because a unit dislocation is specifically defined by having a Burgers vector that corresponds to a perfect lattice vector. Option B is a strong distractor because it appeals to the intuitive but incorrect notion that 'unit' implies smallest magnitude, while in reality some crystals allow smaller partial dislocations. Option C exploits confusion with dislocation conservation principles rather than Burgers vector definition. Option D describes a characteristic of some unit dislocations but not their defining feature, creating a 'partially correct' trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1474, "question": "Under the condition of no solid-phase diffusion and complete liquid-phase mixing, constitutional supercooling cannot occur during the solidification of solid solutions.", "answer": "Correct", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（Correct），符合判断题的特征 | 知识层次: 题目考查对固溶体凝固过程中成分过冷条件的基本概念记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度等级。题目考察的是对\"成分过冷\"这一基础概念的理解，需要考生掌握在特定条件下（无固相扩散和完全液相混合）成分过冷是否会发生的基本原理。虽然涉及多个条件限制，但核心概念较为明确，不需要复杂的分析推理过程，属于中等偏下的难度水平。", "convertible": true, "correct_option": "Correct", "choice_question": "Under the condition of no solid-phase diffusion and complete liquid-phase mixing, constitutional supercooling cannot occur during the solidification of solid solutions.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "Under the condition of no solid-phase diffusion and complete liquid-phase mixing, constitutional supercooling cannot occur during the solidification of solid solutions.", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "Constitutional supercooling requires solute buildup at the solid-liquid interface due to incomplete mixing in the liquid phase and/or limited solid-phase diffusion. With complete liquid-phase mixing (uniform composition) and no solid-phase diffusion (no solute redistribution), there is no mechanism for solute segregation that would lead to constitutional supercooling. This is a subtle condition where the statement holds true, contrary to general cases where constitutional supercooling is common.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2326, "question": "In an aluminum specimen, the dislocation density within the grains was measured to be 2×10^12 m^−2. Assuming all dislocations are edge dislocations and are entirely concentrated at subgrain boundaries (i.e., low-angle grain boundaries), with their Burgers vector b=a/2⟨110⟩. If the cross-sections of the subgrain boundaries are all regular hexagons, and the tilt angle between subgrains is 2°, calculate the dislocation spacing at the subgrain boundary (given the lattice constant of aluminum a=0.404 nm).", "answer": "The dislocation spacing D is calculated by the formula D = b / θ, where b is the Burgers vector and θ is the tilt angle. The Burgers vector b = (√2/2) × 0.404 nm = 0.286 nm. The tilt angle θ = 2° = 2 × (3.14/180) rad = 0.0349 rad. Therefore, D = 0.286 nm / 0.0349 = 8.188 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及具体的物理量（如Burgers向量、倾斜角度）和数学运算（如角度转换、除法运算），最终需要得出一个具体的数值结果（位错间距）。解答过程完全基于计算步骤，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括Burgers向量的计算、角度转换以及最终应用公式计算位错间距。虽然涉及的概念和公式较为基础，但需要将这些知识点关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解位错密度、柏氏矢量、小角度晶界等概念，并进行多步计算和单位转换。虽然题目提供了计算公式，但需要正确应用和综合多个知识点才能得出答案。", "convertible": true, "correct_option": "8.188 nm", "choice_question": "In an aluminum specimen, the dislocation density within the grains was measured to be 2×10^12 m^−2. Assuming all dislocations are edge dislocations and are entirely concentrated at subgrain boundaries (i.e., low-angle grain boundaries), with their Burgers vector b=a/2⟨110⟩. If the cross-sections of the subgrain boundaries are all regular hexagons, and the tilt angle between subgrains is 2°, calculate the dislocation spacing at the subgrain boundary (given the lattice constant of aluminum a=0.404 nm). The dislocation spacing D is:", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion to a multiple-choice format. The correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.188 nm", "B": "4.094 nm", "C": "16.376 nm", "D": "5.796 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (8.188 nm) calculated using D = b/θ where b = a/√2 = 0.286 nm and θ = 2° (0.0349 radians). B is half the correct value, exploiting the common error of forgetting to convert degrees to radians. C is double the correct value, targeting those who might confuse tilt angle with misorientation angle. D is derived from incorrect Burgers vector calculation (using a/2 instead of a/√2), a common mistake in FCC crystals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1880, "question": "Under the same system and the same degree of supercooling, the heterogeneous nucleation rate is always the homogeneous nucleation rate. A. Greater than or equal to B. Less than or equal to C. Equal to D. Not necessarily", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查的是对均相成核和非均相成核速率比较的基本概念记忆和理解，属于基础概念层次的知识点。 | 难度: 在选择题型中，该题目属于基础概念记忆层次，考察的是对异质成核和均质成核速率关系的直接记忆。虽然需要理解\"相同系统和相同过冷度\"条件下的比较关系，但选项提供了明确的对比方向（A选项直接给出了正确关系），不需要复杂的分析或推导。因此属于概念理解和简单辨析的难度等级。", "convertible": true, "correct_option": "A. Greater than or equal to", "choice_question": "Under the same system and the same degree of supercooling, the heterogeneous nucleation rate is always the homogeneous nucleation rate.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress for slip in FCC metals", "B": "The Peierls-Nabarro stress for dislocation motion in BCC metals", "C": "The theoretical shear strength of a perfect crystal", "D": "The yield strength of a polycrystalline sample" }, "correct_answer": "B", "explanation": "The Peierls-Nabarro stress describes the periodic resistance to dislocation motion in BCC metals, which is temperature-dependent due to the non-planar core structure of screw dislocations. Option A is incorrect because CRSS in FCC metals is relatively temperature-independent. Option C is incorrect as it represents an ideal strength value. Option D is incorrect because yield strength incorporates grain boundary effects. The question exploits AI's difficulty in distinguishing between different types of strength measures and their temperature dependencies.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3410, "question": "Compare the alloying direction of high-temperature structural steel and room-temperature structural steel", "answer": "The alloying direction of high-temperature structural steel focuses on adding elements that improve thermal strength and thermal stability (such as Cr, Mo, W, Si, Al, etc.), while the alloying direction of room-temperature structural steel pays more attention to improving strength, toughness, and other room-temperature properties.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种钢材的合金化方向，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求比较两种不同类型结构钢的合金化方向，涉及对高温结构钢和室温结构钢合金元素选择的理解和应用。虽然题目不涉及复杂计算，但需要对两种钢的性能要求和合金元素的作用有较深入的理解，并进行综合分析。这属于中等应用层次，需要概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解高温结构钢和室温结构钢的合金化方向，并比较两者之间的差异。题目要求考生掌握相关元素的作用及其在不同温度条件下的应用，涉及多步概念关联和综合分析。", "convertible": true, "correct_option": "The alloying direction of high-temperature structural steel focuses on adding elements that improve thermal strength and thermal stability (such as Cr, Mo, W, Si, Al, etc.), while the alloying direction of room-temperature structural steel pays more attention to improving strength, toughness, and other room-temperature properties.", "choice_question": "Which of the following correctly compares the alloying direction of high-temperature structural steel and room-temperature structural steel?", "conversion_reason": "The answer is a standard and well-defined comparison between two concepts, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High-temperature steel prioritizes thermal stability elements (Cr, Mo) while room-temperature steel focuses on strength/toughness enhancers (Mn, Ni)", "B": "Both types primarily use carbon content variation for property control, with minimal alloying differences", "C": "High-temperature steel requires rare earth elements for grain refinement, unlike room-temperature steel", "D": "Room-temperature steel uses more alloying elements overall to compensate for lack of thermal stabilization" }, "correct_answer": "A", "explanation": "Correct answer A precisely distinguishes the fundamental alloying philosophy difference. B is wrong because it oversimplifies carbon's role and ignores distinct alloying strategies. C uses a 'grain refinement' red herring that's partially true but not the primary differentiator. D reverses the actual alloying quantity relationship, exploiting the common misconception that high-temperature applications require fewer additives.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4268, "question": "For some metal alloy, a true stress of 415 MPa(60,175 psi) produces a plastic true strain of 0.475 . How much will a specimen of this material elongate when a true stress of 325 MPa(46,125 psi) is applied if the original length is 300mm (11.8 in.)? Assume a value of 0.25 for the strain-hardening exponent n.", "answer": "the specimen will elongate by 58.8 mm (2.31 \\text{ in}).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及金属合金的真实应力、真实应变和应变硬化指数的计算，最终需要求出伸长量。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及真实应力-应变关系的公式应用，需要理解应变硬化指数的概念，并进行数值计算。虽然不涉及复杂的综合分析或创新应用，但比简单的直接套用公式更复杂。 | 难度: 在选择题中属于中等偏上难度，需要理解塑性应变、应变硬化指数等概念，并进行多步计算和综合分析。题目涉及真实应力-应变关系的应用，要求考生能够正确运用公式推导和单位转换，同时需要一定的数学计算能力。虽然题目提供了部分参数，但解题过程仍需要较强的逻辑思维和计算能力。", "convertible": true, "correct_option": "the specimen will elongate by 58.8 mm (2.31 in)", "choice_question": "For some metal alloy, a true stress of 415 MPa(60,175 psi) produces a plastic true strain of 0.475. How much will a specimen of this material elongate when a true stress of 325 MPa(46,125 psi) is applied if the original length is 300mm (11.8 in.)? Assume a value of 0.25 for the strain-hardening exponent n.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "58.8 mm (2.31 in)", "B": "47.3 mm (1.86 in)", "C": "72.5 mm (2.85 in)", "D": "36.2 mm (1.43 in)" }, "correct_answer": "A", "explanation": "The correct answer is A because it properly applies the strain-hardening exponent (n=0.25) in the Hollomon equation (σ=Kε^n) to calculate the true strain at 325 MPa, then converts to engineering strain for elongation. Option B is a common error from misapplying the exponent as 0.475. Option C results from confusing true strain with engineering strain. Option D arises from incorrect unit conversion between MPa and psi.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2020, "question": "Analyze the type of solid solution formed by B in α-Fe and γ-Fe, its location, and the solubility (mole fraction). The atomic radii of the elements are as follows: B: 0.091 nm, α-Fe: 0.124 nm, γ-Fe: 0.126 nm", "answer": "In α-Fe, due to the larger atomic size of B, it is more difficult to dissolve interstitially, sometimes partially dissolving substitutionally, forming interstitial or substitutional solid solutions, with relatively low solubility. In γ-Fe, B forms an interstitial solid solution, located at the center of octahedral interstitial sites, with slightly higher solubility than in α-Fe.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析B在α-Fe和γ-Fe中形成的固溶体类型、位置和溶解度，需要文字解释和论述，答案也是以文字形式详细解释，符合简答题的特征。 | 知识层次: 题目要求分析B在α-Fe和γ-Fe中形成的固溶体类型、位置和溶解度，涉及原子半径比较、固溶体类型判断以及溶解度差异的解释。这需要理解固溶体的基本概念，并能将原子半径与固溶体类型关联起来，同时进行综合分析。虽然不涉及复杂计算，但需要对多个概念进行关联和解释，属于中等应用层次。 | 难度: 在选择题型中，该题目需要考生综合理解原子半径差异对固溶体类型的影响，同时分析不同晶体结构（α-Fe和γ-Fe）中溶质原子的溶解方式和位置选择。题目涉及多个概念的关联（间隙固溶体、置换固溶体、八面体间隙位置）和比较分析（两种铁的同素异构体中的溶解度差异），解题步骤较为复杂，需要考生具备较强的综合分析能力。在选择题型内，这类需要多角度分析论述的题目属于较高难度等级。", "convertible": true, "correct_option": "In α-Fe, due to the larger atomic size of B, it is more difficult to dissolve interstitially, sometimes partially dissolving substitutionally, forming interstitial or substitutional solid solutions, with relatively low solubility. In γ-Fe, B forms an interstitial solid solution, located at the center of octahedral interstitial sites, with slightly higher solubility than in α-Fe.", "choice_question": "Analyze the type of solid solution formed by B in α-Fe and γ-Fe, its location, and the solubility (mole fraction). The atomic radii of the elements are as follows: B: 0.091 nm, α-Fe: 0.124 nm, γ-Fe: 0.126 nm. Which of the following statements is correct?", "conversion_reason": "The answer is a standard description of the solid solution formed by B in α-Fe and γ-Fe, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In α-Fe, B forms a substitutional solid solution due to its relatively large size, with solubility below 0.02 mole fraction", "B": "In both α-Fe and γ-Fe, B exclusively forms interstitial solid solutions at tetrahedral sites with similar solubility", "C": "In γ-Fe, B forms an interstitial solid solution at octahedral sites with solubility exceeding 0.1 mole fraction", "D": "B cannot form any solid solution in α-Fe due to severe lattice distortion, but dissolves interstitially in γ-Fe" }, "correct_answer": "A", "explanation": "The correct answer is A because B's radius (0.091 nm) is too large for ideal interstitial sites in α-Fe (radius ratio > 0.59), forcing partial substitutional dissolution with limited solubility. Option B is wrong by suggesting exclusive interstitial solutions and incorrect site locations. Option C overestimates solubility in γ-Fe (actual <0.03). Option D is incorrect by completely denying α-Fe solubility while ignoring the partial substitutional mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 7, "question": "What are the characteristics of covalent bonds?", "answer": "The characteristics of covalent bonds are directionality and saturation, and the bonding force is also very strong.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释共价键的特性，答案以文字论述的形式给出，没有选项、判断或计算要求 | 知识层次: 题目考查共价键的基本特性（方向性和饱和性）的记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目要求考生不仅记忆共价键的基本定义，还需要理解并描述其特性（方向性和饱和性）以及键的强度。这超出了简单的定义回忆（等级1），但尚未达到需要阐述复杂概念体系的程度（等级3）。因此属于概念解释和描述的中等难度。", "convertible": true, "correct_option": "directionality and saturation, and the bonding force is also very strong", "choice_question": "Which of the following are characteristics of covalent bonds?", "conversion_reason": "The answer is a standard description of covalent bonds' characteristics, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "directionality and saturation, and the bonding force is also very strong", "B": "non-directionality and high electrical conductivity", "C": "saturation only, with variable bond strength", "D": "directionality only, with weak bonding forces" }, "correct_answer": "A", "explanation": "The correct answer is A because covalent bonds are characterized by directionality (due to orbital overlap) and saturation (fixed number of bonds per atom), with strong bonding forces. Option B is incorrect as it describes metallic bonding properties (non-directional, conductive). Option C is a half-truth trap - while covalent bonds do show saturation, their strength is consistently strong, not variable. Option D exploits the common misconception that directional bonds must be weak, ignoring covalent bonds' actual high strength.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4889, "question": "In an aligned and continuous carbon fiber-reinforced nylon 6,6 composite, the fibers are to carry 97% of a load applied in the longitudinal direction. What will be the tensile strength of this composite? Assume that the matrix stress at fiber failure is 50 MPa (7250 psi).", "answer": "the tensile strength of this composite is 1070 mpa (155,000 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解复合材料的拉伸强度，答案是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，涉及复合材料中纤维和基体的应力分配，需要理解纤维增强复合材料的力学行为，并应用相关公式进行计算。虽然题目给出了部分参数，但仍需综合分析才能得出最终结果。 | 难度: 在选择题中属于中等偏上难度，需要理解复合材料力学的基本概念（如载荷分配、纤维与基体的应力关系），并进行多步骤计算（包括载荷分配比例转换、基体应力叠加等综合运算）。虽然题目提供了关键参数，但解题过程涉及多个知识点的关联应用，比单纯的概念选择题更复杂。", "convertible": true, "correct_option": "1070 MPa (155,000 psi)", "choice_question": "In an aligned and continuous carbon fiber-reinforced nylon 6,6 composite, the fibers are to carry 97% of a load applied in the longitudinal direction. What will be the tensile strength of this composite? Assume that the matrix stress at fiber failure is 50 MPa (7250 psi).", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1070 MPa (155,000 psi)", "B": "515 MPa (74,700 psi)", "C": "2060 MPa (299,000 psi)", "D": "50 MPa (7,250 psi)" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the rule of mixtures for composite strength, where the composite strength is the sum of the fiber strength (97% of load) and matrix stress at fiber failure (3% of load). The high difficulty distractors exploit common errors: B) Uses the matrix stress as the dominant contribution (reversed load sharing ratio), C) Misapplies the rule of mixtures by adding fiber and matrix strengths directly without considering load distribution, D) Takes only the matrix stress value ignoring fiber contribution entirely.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 890, "question": "If diffusion occurs in a Cu-Al diffusion couple, in which direction will the interface marker move?", "answer": "When diffusion occurs in a Cu-Al diffusion couple, the interface marker will move toward the Al side.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要解释扩散偶中界面标记移动的方向，答案以文字解释的形式给出，没有提供选项或要求计算，属于简答题类型。 | 知识层次: 题目需要理解扩散偶中界面标记移动的机制，涉及不同金属的扩散速率差异和Kirkendall效应的概念。虽然不涉及复杂计算，但需要综合分析扩散方向和速率差异对界面标记位置的影响，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解扩散偶中界面标记移动的原理，并综合分析Cu-Al扩散偶的特性。虽然不需要复杂的计算，但要求考生掌握扩散方向与浓度梯度的关系，并能将这一概念应用到具体材料体系中。", "convertible": true, "correct_option": "toward the Al side", "choice_question": "If diffusion occurs in a Cu-Al diffusion couple, in which direction will the interface marker move?", "conversion_reason": "The answer is a standard and specific direction, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Toward the Al side due to faster Cu diffusion in Al", "B": "Toward the Cu side due to higher Al vacancy concentration", "C": "Remains stationary as diffusion rates are equal", "D": "Oscillates due to competing Kirkendall effects" }, "correct_answer": "A", "explanation": "The correct answer is A because Cu has a higher intrinsic diffusion coefficient in Al than vice versa, causing more Cu atoms to move into Al and shifting the marker toward Al. Option B exploits the common misconception that higher vacancy concentration determines marker movement. Option C traps those assuming equal diffusion rates without considering atomic size effects. Option D introduces a plausible-sounding but non-existent oscillation phenomenon to catch overconfident predictions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2650, "question": "It is known that pure titanium at 900°C is β-Ti (bcc structure) with a lattice constant a=0.3307nm. Calculate the interplanar spacing of the (112) plane.", "answer": "For the bcc structure, there is an additional plane when h+k+l=odd number. d_(112)=a/√(h²+k²+l²)=0.3307/√(1²+1²+2²)=0.135nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，具体涉及计算(112)晶面的晶面间距，解答过程需要使用给定的晶格常数和公式进行计算。 | 知识层次: 题目要求直接应用已知的bcc结构晶面间距公式进行计算，涉及基本的公式套用和简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要理解bcc结构的额外平面条件（h+k+l=奇数），但主要解题步骤是直接套用已知的晶面间距公式d=a/√(h²+k²+l²)进行简单计算。不需要多个公式组合或复杂推导，符合等级2\"简单公式应用计算\"的标准。", "convertible": true, "correct_option": "0.135nm", "choice_question": "It is known that pure titanium at 900°C is β-Ti (bcc structure) with a lattice constant a=0.3307nm. The interplanar spacing of the (112) plane is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.135 nm", "B": "0.191 nm", "C": "0.330 nm", "D": "0.165 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.135 nm) calculated using the bcc interplanar spacing formula for (112) planes: d=a/√(h²+k²+l²)=0.3307/√6. B (0.191 nm) is the (110) spacing, a common confusion when planes have similar indices. C (0.330 nm) is the raw lattice constant, exploiting AI's tendency to overlook calculations. D (0.165 nm) is half the lattice constant, a trap for those misapplying simple fractions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2930, "question": "The flexibility of polymer materials mainly depends on the mobility of . (A) Main chain segments (B) Side groups (C) Functional groups or atoms within side groups", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查聚合物材料柔韧性的基本概念，即主链段的运动性，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别聚合物材料柔韧性的主要决定因素（主链段的活动性），无需复杂辨析或深度理解。选项直接对应基础知识点，属于简单概念识别。", "convertible": true, "correct_option": "Main chain segments", "choice_question": "The flexibility of polymer materials mainly depends on the mobility of .", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The entanglement density of polymer chains", "B": "The degree of crystallinity in the amorphous regions", "C": "The mobility of pendant phenyl rings", "D": "The reptation dynamics of chain ends" }, "correct_answer": "A", "explanation": "The correct answer is A because polymer flexibility is fundamentally governed by the entanglement density which restricts segmental mobility. Option B exploits the common misconception that crystallinity affects flexibility directly in amorphous regions. Option C uses a specific chemical structure (phenyl rings) to trigger incorrect chemical intuition. Option D strategically misapplies the reptation theory by focusing on chain ends rather than the main chain dynamics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3274, "question": "What is the actual grain size of austenite?", "answer": "The size of austenite grains obtained under a specific heat treatment condition is generally referred to as the actual grain size.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"actual grain size of austenite\"进行文字解释和论述，答案提供了概念性的说明而非选择、判断或计算。 | 知识层次: 题目考查对奥氏体实际晶粒尺寸这一基本概念的记忆和理解，属于材料科学中的基础概念知识，不需要复杂的应用或分析。 | 难度: 该题目属于基础概念记忆类型，仅需识别和回忆\"实际晶粒尺寸\"的定义。选择题型中正确选项直接给出了明确答案，无需复杂推理或概念比较，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The size of austenite grains obtained under a specific heat treatment condition is generally referred to as the actual grain size.", "choice_question": "What is the actual grain size of austenite?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The size of austenite grains obtained under a specific heat treatment condition", "B": "The theoretical maximum grain size predicted by the Hall-Petch relationship", "C": "The average grain size measured at room temperature after quenching", "D": "The critical grain size required for recrystallization to occur" }, "correct_answer": "A", "explanation": "The correct answer is A because the actual grain size refers specifically to the size obtained under given heat treatment conditions. Option B is incorrect as it confuses actual grain size with theoretical predictions. Option C is a measurement trap, as room temperature measurement may not reflect the actual austenite grain size due to phase transformations. Option D introduces an unrelated concept of recrystallization critical size, which is a different material property.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 320, "question": "What is the angle between the [100] and [111] crystallographic directions in face-centered cubic metals?", "answer": "The angle between crystallographic planes cosφ=1/√3; φ=54.7°", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算面心立方金属中[100]和[111]晶向之间的夹角，需要通过公式计算得出具体数值（54.7°），属于典型的计算题类型。 | 知识层次: 题目涉及基本的晶体学方向计算，仅需套用已知的向量夹角公式（cosφ = (h1h2 + k1k2 + l1l2)/√(h1²+k1²+l1²)√(h2²+k2²+l2²)）进行一步计算，无需多步推导或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。解题仅需应用基本的向量点积公式cosφ = (h1h2 + k1k2 + l1l2)/√(h1²+k1²+l1²)√(h2²+k2²+l2²)，将[100]和[111]方向代入即可得到cosφ=1/√3。不需要额外的推导或复杂计算步骤，完全符合等级1\"单一公式直接计算\"的特征。", "convertible": true, "correct_option": "54.7°", "choice_question": "What is the angle between the [100] and [111] crystallographic directions in face-centered cubic metals?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "54.7°", "B": "45.0°", "C": "60.0°", "D": "35.3°" }, "correct_answer": "A", "explanation": "The correct answer is A (54.7°) as calculated using the dot product formula for cubic crystals. Option B (45.0°) exploits the common misconception of simply averaging angles. Option C (60.0°) uses the angle between [111] directions as a distraction. Option D (35.3°) is derived from incorrect trigonometric manipulation of the direction indices.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 244, "question": "How should the cooling rate of high iron composition (P<1.38) in the burning zone be controlled?", "answer": "For compositions with an alumina modulus P<1.38, the melt cooling and crystallization process passes through the WT2 boundary, where the liquid phase absorbs C2S back and precipitates CsS and C4AF. Therefore, the slower the clinker cooling rate, the closer it approaches equilibrium, and the more fully C2S is absorbed back. The content of CS in the clinker will increase, which is beneficial for cement quality. Thus, for clinker with P<1.38, the cooling rate in the burning zone should be appropriately slowed down.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对高铁成分（P<1.38）在燃烧区的冷却速率控制进行解释和论述，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及对高铁成分在燃烧区冷却速率的控制机制的理解，需要综合运用材料科学中的相变原理和水泥熟料形成过程的知识。解答过程中需要分析冷却速率对相变路径和最终产物组成的影响，并基于此提出控制策略，体现了较高的认知层次和综合分析能力。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅要理解高铁成分（P<1.38）在燃烧区的冷却速率控制原理，还需要掌握熔体冷却和结晶过程中通过WT2边界时液相吸收C2S并析出CsS和C4AF的复杂机理。此外，题目还要求考生能够推理分析冷却速率对水泥质量的影响，并综合运用这些知识得出正确的控制策略。这种题目不仅考察了多个复杂概念的掌握，还需要考生进行深层次的机理解释和综合推理，因此在选择题型中属于最高难度。", "convertible": true, "correct_option": "The cooling rate should be appropriately slowed down.", "choice_question": "How should the cooling rate of high iron composition (P<1.38) in the burning zone be controlled?", "conversion_reason": "The answer is a specific recommendation that can be directly used as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice format by providing plausible options including the correct one.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The cooling rate should be appropriately slowed down", "B": "The cooling rate should be maximized to prevent iron oxidation", "C": "The cooling rate should match the thermal conductivity of pure iron", "D": "The cooling rate should follow the Arrhenius equation for phase transformation" }, "correct_answer": "A", "explanation": "The correct answer is A because slowing the cooling rate prevents cracking and stress buildup in high iron compositions. Option B is a cognitive bias trap - while fast cooling prevents oxidation, it causes detrimental internal stresses. Option C exploits material property confusion by suggesting to match pure iron's conductivity, ignoring the alloy's complex behavior. Option D is a professional intuition trap - while Arrhenius equation is relevant, it doesn't directly dictate cooling rate control in this context.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4039, "question": "When an electric field is applied, in which direction are the free electrons accelerated?(a) Opposite to the direction of the electric field.(b) In the same direction as the electric field.", "answer": "When an electric field is applied, the free electrons are accelerated in the direction opposite to that of the field.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目提供了两个选项（a和b），要求从中选择正确的答案。 | 知识层次: 题目考查对电场中自由电子运动方向这一基本概念的记忆和理解，属于基础概念层次。 | 难度: 该题目属于基础概念记忆类型，仅需直接回忆自由电子在电场中的运动方向这一基本原理，无需复杂辨析或深度理解。在选择题型中，此类直接考察定义和基本原理的题目通常属于最简单级别。", "convertible": true, "correct_option": "Opposite to the direction of the electric field.", "choice_question": "When an electric field is applied, in which direction are the free electrons accelerated?", "conversion_reason": "The original question is already in a multiple-choice format with two distinct options, and the answer clearly corresponds to one of the provided options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Opposite to the direction of the electric field", "B": "In the same direction as the electric field", "C": "Perpendicular to both electric and magnetic fields", "D": "Random direction due to thermal motion" }, "correct_answer": "A", "explanation": "The correct answer is A because free electrons, being negatively charged, are accelerated in the direction opposite to the applied electric field. Option B is a common misconception that exploits the cognitive bias of equating 'field direction' with 'particle motion'. Option C is a professional intuition trap that introduces irrelevant magnetic field considerations. Option D is a multi-level verification trap that combines a true fact (thermal motion) with an incorrect conclusion about the net effect of an applied field.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2212, "question": "When cold-drawn copper wires are used as overhead conductors (requiring certain strength), what final heat treatment process should be adopted?", "answer": "Stress relief annealing (low-temperature annealing) should be adopted.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释应采取何种最终热处理工艺，答案需要文字解释和论述，而非选择、判断或计算。 | 知识层次: 题目要求根据具体应用场景（冷拉铜线作为架空导线）选择适当的热处理工艺，需要理解材料性能与工艺之间的关系，并进行综合分析。虽然答案较为直接，但需要将材料科学原理与实际应用相结合，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解铜线作为架空导体的应用场景及其强度要求，并关联到适当的热处理工艺。虽然题目涉及多步概念关联和综合分析，但在选择题型中，通过排除法可以缩小选项范围，降低解题难度。", "convertible": true, "correct_option": "Stress relief annealing (low-temperature annealing)", "choice_question": "When cold-drawn copper wires are used as overhead conductors (requiring certain strength), what final heat treatment process should be adopted?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Stress relief annealing (low-temperature annealing)", "B": "Solution heat treatment followed by quenching", "C": "Full recrystallization annealing at 500°C", "D": "Precipitation hardening at 300°C" }, "correct_answer": "A", "explanation": "The correct answer is A because cold-drawn copper wires require stress relief to maintain their strength while eliminating residual stresses from cold working. Option B is incorrect as solution treatment would completely erase the cold-worked structure needed for strength. Option C is a strong distractor because recrystallization annealing is common for copper, but would excessively soften the conductor. Option D exploits confusion with age-hardenable alloys, though pure copper cannot be precipitation hardened.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3804, "question": "Consider a Pb-15% Sn alloy. During solidification, determine the composition of the first solid to form.", "answer": "8% Sn", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求确定合金凝固过程中第一个固体的成分，需要基于相图和合金凝固原理进行解释和论述，答案是一个具体的数值（8% Sn），但解答过程需要文字说明和理论支持。 | 知识层次: 题目需要理解相图的基本原理，并能够根据给定的合金成分在相图上确定初始凝固固相的成分。这涉及到多步的思维过程，包括理解相图、识别相关相区以及应用杠杆定律等概念。虽然不涉及复杂的计算或深度分析，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解相图的基本概念（如液相线和固相线），并能根据给定的合金成分（Pb-15% Sn）在相图上定位，进而确定首先形成的固相成分（8% Sn）。这涉及到对二元相图的理解和应用，但不需要复杂的多步计算或深度关联性分析。", "convertible": true, "correct_option": "8% Sn", "choice_question": "Consider a Pb-15% Sn alloy. During solidification, what is the composition of the first solid to form?", "conversion_reason": "The answer is a specific value (8% Sn), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8% Sn", "B": "15% Sn", "C": "2% Sn", "D": "19% Sn" }, "correct_answer": "A", "explanation": "The correct answer is A (8% Sn) because the first solid to form during solidification of a Pb-15% Sn alloy will have the composition at the solidus line of the phase diagram, which is approximately 8% Sn for this alloy system. Option B (15% Sn) is a cognitive bias trap - it seems intuitive that the solid would match the overall composition, but this ignores phase equilibrium principles. Option C (2% Sn) exploits professional intuition by suggesting an extreme value that might seem plausible for pure lead, but is too low for this alloy. Option D (19% Sn) is a multi-level verification trap - it's the liquid composition when the last solid forms, reversed to confuse those with partial phase diagram knowledge.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4045, "question": "The electrical conductivity of an extrinsic semiconductor is(a) Characteristic of the high-purity material.(b) due to the presence of impurities.", "answer": "The electrical conductivity of an extrinsic semiconductor is due to the presence of impurities.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目提供了两个选项(a)和(b)，要求从中选择关于外征半导体导电性的正确描述 | 知识层次: 题目考查对半导体导电性基本原理的记忆和理解，属于基础概念层次 | 难度: 该题目属于基础概念记忆类型，仅需识别并记忆外征半导体的电导率是由杂质引起的这一基本事实。在选择题型中，这种直接考察定义或分类的题目属于最简单的难度等级，不需要复杂的理解或分析过程。", "convertible": true, "correct_option": "due to the presence of impurities", "choice_question": "The electrical conductivity of an extrinsic semiconductor is", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer is clearly one of the provided options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Directly proportional to the square root of dopant concentration", "B": "Inversely proportional to the mobility of minority carriers", "C": "Primarily determined by the intrinsic carrier concentration", "D": "Independent of temperature above 300K" }, "correct_answer": "A", "explanation": "The correct answer is A because conductivity in extrinsic semiconductors is proportional to both carrier concentration (square root of dopant concentration) and mobility. B is a cognitive bias trap - while minority carriers exist, they don't dominate conductivity. C exploits the common confusion between intrinsic and extrinsic behavior. D is a multi-level trap - while extrinsic behavior dominates at room temp, temperature dependence never completely disappears due to mobility effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1443, "question": "For a screw dislocation line, what is the relationship between its Burgers vector and the dislocation line?", "answer": "Parallel", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释螺位错线的Burgers矢量与位错线之间的关系，需要文字描述而非选择或判断 | 知识层次: 题目考查对螺位错基本概念的记忆和理解，即螺位错的Burgers矢量与位错线的关系，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆基本的定义性知识，即螺型位错线的柏氏矢量与位错线的关系是平行的。不需要进行概念解释或复杂分析，属于最基础的概念记忆层次。", "convertible": true, "correct_option": "Parallel", "choice_question": "For a screw dislocation line, what is the relationship between its Burgers vector and the dislocation line?", "conversion_reason": "The answer is a standard term (Parallel), which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Parallel", "B": "Perpendicular", "C": "At a 45° angle", "D": "The relationship depends on the crystal structure" }, "correct_answer": "A", "explanation": "The Burgers vector of a screw dislocation is always parallel to the dislocation line by definition. Option B exploits confusion with edge dislocations where the Burgers vector is perpendicular. Option C creates a false intermediate case that doesn't exist in dislocation theory. Option D introduces a plausible-sounding but incorrect conditionality that could mislead models relying on pattern matching with other material properties that do vary with crystal structure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 631, "question": "Give two examples to illustrate the phenomenon of uphill diffusion in metals", "answer": "Examples of uphill diffusion in metals include the formation of Cottrell atmospheres and the spinodal decomposition process.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求给出两个例子来说明金属中的上坡扩散现象，答案提供了具体的例子并进行了简要解释，符合简答题的特征。 | 知识层次: 题目要求列举并解释金属中上坡扩散的现象实例，需要理解上坡扩散的概念，并能将其与具体的金属学现象（如Cottrell气团和调幅分解）联系起来。这涉及到对扩散机制和相变过程的中等程度理解和应用，而不仅仅是基础概念的记忆。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生不仅知道\"uphill diffusion\"的定义，还要能联想到具体的金属学现象（Cottrell atmospheres和spinodal decomposition），这需要对扩散原理和金属材料行为有较深入的理解。虽然不涉及计算，但需要将抽象概念与具体实例关联起来，属于概念关联和综合分析层次的要求。", "convertible": true, "correct_option": "Examples of uphill diffusion in metals include the formation of Cottrell atmospheres and the spinodal decomposition process.", "choice_question": "Which of the following are examples of uphill diffusion in metals?", "conversion_reason": "The answer is a standard description of examples, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cottrell atmospheres formation around dislocations", "B": "Fickian diffusion in dilute alloys", "C": "Vacancy-mediated diffusion in pure metals", "D": "Grain boundary diffusion at high temperatures" }, "correct_answer": "A", "explanation": "Correct answer A represents a classic example of uphill diffusion where solute atoms move against their concentration gradient to segregate around dislocations. Option B is a cognitive bias trap - Fickian diffusion always follows concentration gradients. Option C exploits professional intuition by presenting a fundamentally correct but irrelevant mechanism. Option D is a multi-level verification trap combining a real phenomenon (grain boundary diffusion) with an incorrect application to uphill diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4408, "question": "Compare investment casting technique", "answer": "For investment casting, a single-piece mold is used, which is not reusable; it results in high dimensional accuracy, good reproduction of detail, and a fine surface finish; and casting rates are low.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较和描述投资铸造技术的特点，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对投资铸造技术的基本概念和特点的记忆和理解，如模具类型、尺寸精度、表面光洁度等，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆，但需要考生理解并描述投资铸造技术的多个特点（如模具类型、尺寸精度、细节再现、表面质量和铸造速率），而不仅仅是简单的定义记忆。这要求考生对概念有一定的理解和整合能力，但不需要进行复杂的比较分析或概念体系阐述。", "convertible": true, "correct_option": "For investment casting, a single-piece mold is used, which is not reusable; it results in high dimensional accuracy, good reproduction of detail, and a fine surface finish; and casting rates are low.", "choice_question": "Which of the following statements accurately describes the investment casting technique?", "conversion_reason": "The answer is a standard description of the investment casting technique, which can be used as the correct option in a multiple-choice question. The original question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "For investment casting, a single-piece mold is used, which is not reusable; it results in high dimensional accuracy, good reproduction of detail, and a fine surface finish; and casting rates are low.", "B": "Investment casting employs reusable multi-piece molds, achieves moderate surface finish, and allows for high production rates due to rapid mold cycling.", "C": "The investment casting process uses ceramic molds that can be reused up to 5 times, provides excellent dimensional control for large castings, but requires post-casting machining for fine details.", "D": "In investment casting, the wax pattern is surrounded by a permanent metal mold, enabling both high production rates and exceptional surface finish simultaneously." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes investment casting's key characteristics: single-use ceramic mold (non-reusable), high precision, fine details, and low production rates. Option B incorrectly suggests reusable molds and high rates - these are die casting features. Option C's claim of reusable ceramic molds contradicts investment casting fundamentals. Option D's permanent metal mold description is completely wrong for this process, mixing up investment casting with permanent mold casting.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4307, "question": "Give the approximate temperature at which creep deformation becomes an important consideration for tungsten.", "answer": "for w: 1200 degrees c (2190 degrees f)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从多个选项中选择或判断对错，也不需要复杂的计算过程。答案是一个具体的数值，属于简答题的范畴。 | 知识层次: 题目考查对钨材料蠕变变形温度这一特定数值的记忆，属于基础概念的记忆性知识，不需要复杂的应用或分析过程。 | 难度: 在选择题型中，此题仅需记忆钨的蠕变变形重要温度（1200°C）这一具体数值，属于基础概念记忆层面的简单问题。不需要概念解释或复杂分析，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "1200 degrees C (2190 degrees F)", "choice_question": "At approximately what temperature does creep deformation become an important consideration for tungsten?", "conversion_reason": "The answer is a specific temperature value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1200°C (2190°F)", "B": "800°C (1472°F)", "C": "0.4 × melting temperature (1450°C)", "D": "When yield strength drops below 100 MPa" }, "correct_answer": "A", "explanation": "The correct answer is A because tungsten's high melting point (3422°C) means creep only becomes significant above 1200°C. Option B exploits the common misconception that creep starts at lower temperatures for all metals. Option C uses a valid rule-of-thumb (0.4×Tm) but incorrectly applies it to absolute temperature rather than Kelvin. Option D creates confusion by mixing creep onset with an arbitrary strength criterion that doesn't correlate with tungsten's actual creep behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3035, "question": "Rubber is an excellent damping material and friction material due to its outstanding (1). A. High elasticity B. Viscoelasticity C. Plastic D. Anti-friction", "answer": "(1)A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查橡胶材料的基本特性记忆，属于基础概念的记忆和理解 | 难度: 在选择题型中，该题目仅需识别橡胶的基本特性（高弹性），属于直接记忆的基础概念，无需复杂辨析或深度理解。题目选项设置简单明确，正确选项A与其他选项区分明显，符合等级1的简单概念识别标准。", "convertible": true, "correct_option": "A. High elasticity", "choice_question": "Rubber is an excellent damping material and friction material due to its outstanding", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The strain-rate sensitivity exponent (m-value) in superplastic deformation", "B": "The Hall-Petch coefficient for nanocrystalline materials", "C": "The Peierls-Nabarro stress in bcc metals", "D": "The stacking fault energy in austenitic stainless steels" }, "correct_answer": "A", "explanation": "The correct answer is A because the strain-rate sensitivity exponent is the key parameter controlling superplastic elongation. Option B exploits the common misconception that grain refinement always improves ductility. Option C traps those who confuse dislocation mobility mechanisms between bcc and fcc metals. Option D targets the intuitive but incorrect association between stacking faults and extreme ductility. All incorrect options are real material parameters that could plausibly relate to deformation, requiring precise domain knowledge to differentiate.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2777, "question": "Based on the diffusion coefficients at 1223K and 1136K, calculate the activation energy Q for interstitial atom diffusion in face-centered cubic metals. The diffusion coefficient at 1223K is 4.34×10⁻⁸m²/s, and at 1136K it is 1.78×10⁻⁸m²/s.", "answer": "According to Arrhenius' law, D = D₀exp(-Q/RT). For two temperatures, we have: D₁/D₂ = exp[(-Q/R)(1/T₁ - 1/T₂)]. Substituting the data: 4.34×10⁻⁸ / 1.78×10⁻⁸ = exp[(-Q/8.314)(1/1223 - 1/1136)]. Solving gives: Q ≈ 1.2×10⁵J/mol.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求基于给定的扩散系数和温度数据，通过Arrhenius方程计算激活能Q，需要应用公式进行数值计算，最终得出具体数值结果。 | 知识层次: 题目需要应用Arrhenius定律进行多步计算，涉及对数运算和温度转换，需要理解扩散系数与温度的关系，并进行综合分析来求解激活能。虽然不涉及复杂的机理分析或创新设计，但比简单的公式应用要求更高的计算能力和概念关联能力。 | 难度: 在选择题中属于中等偏上难度，需要理解Arrhenius定律并进行多步计算，包括对数运算和温度倒数处理。虽然提供了正确选项，但解题过程涉及多个概念的综合应用和较复杂的数学运算，超出了基础选择题的难度。", "convertible": true, "correct_option": "1.2×10⁵J/mol", "choice_question": "Based on the diffusion coefficients at 1223K (4.34×10⁻⁸m²/s) and 1136K (1.78×10⁻⁸m²/s), calculate the activation energy Q for interstitial atom diffusion in face-centered cubic metals.", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.2×10⁵J/mol", "B": "2.4×10⁵J/mol", "C": "8.3×10⁴J/mol", "D": "1.8×10⁵J/mol" }, "correct_answer": "A", "explanation": "正确答案A是通过阿伦尼乌斯方程正确计算得出的激活能值。干扰项B是常见错误，源于将温度倒数差误算为两倍；干扰项C利用了直觉陷阱，接近气体常数R的值但忽略了实际计算关系；干扰项D设计为接近高温扩散系数的数量级，诱导对数值的直观选择。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4796, "question": "Estimate the theoretical fracture strength of a brittle material if it is known that fracture occurs by the propagation of an elliptically shaped surface crack of length 0.5 mm(0.02 in.) and a tip radius of curvature of 5 × 10^{-3} mm\\left(2 × 10^{-4} in\\right), when a stress of 1035 MPa(150,000 psi) is applied.", "answer": "the theoretical fracture strength of the material is 20.7 gpa (3 × 10^{6} psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计材料的理论断裂强度，答案是一个具体的数值结果，解答过程需要运用相关公式进行计算。 | 知识层次: 题目需要进行多步计算，涉及断裂强度的理论公式应用，需要理解裂纹长度、尖端半径与应力之间的关系，并进行数值计算。虽然不涉及复杂的综合分析或机理解释，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解断裂强度的理论计算，涉及多步骤的公式应用和单位转换。题目要求考生能够正确应用应力集中公式，并进行单位换算和数值计算，属于综合性计算问题。虽然题目提供了具体数值，但计算过程需要精确和细心，对考生的概念理解和计算能力有一定要求。", "convertible": true, "correct_option": "20.7 GPa (3 × 10^{6} psi)", "choice_question": "Estimate the theoretical fracture strength of a brittle material if it is known that fracture occurs by the propagation of an elliptically shaped surface crack of length 0.5 mm(0.02 in.) and a tip radius of curvature of 5 × 10^{-3} mm(2 × 10^{-4} in), when a stress of 1035 MPa(150,000 psi) is applied. The theoretical fracture strength is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "20.7 GPa (3 × 10^6 psi)", "B": "10.35 GPa (1.5 × 10^6 psi)", "C": "41.4 GPa (6 × 10^6 psi)", "D": "5.18 GPa (0.75 × 10^6 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the Griffith theory of fracture mechanics where the theoretical fracture strength σ_max = 2σ_0√(a/ρ_t), with σ_0 being the applied stress (1035 MPa), a the crack length (0.25 mm half-length), and ρ_t the tip radius (5×10^-3 mm). Option B is half the correct value, exploiting the common mistake of omitting the factor of 2 in the equation. Option C doubles the correct value, targeting those who might incorrectly square the entire expression. Option D is one-fourth the correct value, preying on the tendency to over-simplify the square root relationship.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3043, "question": "Oxide ceramics have a close-packed structure and exhibit high melting points and chemical stability due to strong ionic bonds.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对氧化物陶瓷基本特性的记忆和理解，包括其紧密堆积结构、高熔点和化学稳定性等基础概念，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆氧化物陶瓷的基本特性（如紧密堆积结构、高熔点、化学稳定性及强离子键）即可做出正确判断，无需深入理解或分析多个概念。", "convertible": true, "correct_option": "√", "choice_question": "Oxide ceramics have a close-packed structure and exhibit high melting points and chemical stability due to strong ionic bonds.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All oxide ceramics exhibit higher thermal conductivity than metals due to their ionic bonding nature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many oxide ceramics have strong ionic bonds, their thermal conductivity varies widely and is generally lower than most metals. This statement incorrectly generalizes all oxide ceramics and misrepresents the relationship between bonding type and thermal conductivity. The key misconceptions are: 1) assuming ionic bonding always leads to high thermal conductivity, 2) ignoring that electron conduction in metals typically gives higher thermal conductivity than phonon conduction in ceramics, and 3) overlooking exceptions like alumina which has moderate conductivity while zirconia is a thermal insulator.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2855, "question": "Calculate the number of Fe3C particles per unit volume N_v, given the volume fraction of Fe3C phase φ_Fe3C=0.06 and the radius of spherical cementite particles r=10×10^-6 m.", "answer": "N_v = φ_Fe3C / (4/3 * π * r^3) = 0.06 / (4/3 * π * (10×10^-6)^3) ≈ 1.43×10^13 (1/m^3)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算并应用公式来求解Fe3C颗粒的单位体积数量，答案也是通过计算得出的具体数值。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，不需要多步推理或综合分析，属于对体积分数和球形颗粒体积公式的直接套用。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算，无需复杂的推理或多步骤操作。题目提供了所有必要的参数，只需将数值代入公式即可得到答案。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "1.43×10^13 (1/m^3)", "choice_question": "Calculate the number of Fe3C particles per unit volume N_v, given the volume fraction of Fe3C phase φ_Fe3C=0.06 and the radius of spherical cementite particles r=10×10^-6 m.", "conversion_reason": "The calculation question has a definite numerical answer, which can be converted into a multiple-choice question format with the correct option being the calculated result.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.43×10^13 (1/m^3)", "B": "2.86×10^13 (1/m^3)", "C": "7.16×10^12 (1/m^3)", "D": "3.58×10^13 (1/m^3)" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula N_v = φ_Fe3C / (4/3 * π * r^3), where φ_Fe3C is the volume fraction and r is the particle radius. Option B is a common mistake where the volume fraction is incorrectly doubled. Option C results from forgetting to cube the radius in the denominator. Option D is obtained by incorrectly squaring instead of cubing the radius in the calculation. These errors exploit common calculation oversights in materials science problems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1020, "question": "Given that for carbon diffusion in γ-Fe, D0=2.0×10^(-5)m²/s, Q=1.4×10^5J/mol, gas constant R=8.314J/(mol·K), calculate the diffusion coefficient D927°C at 927°C.", "answer": "D927°C = D0 * exp(-Q / (R * T)) = 2.0×10^(-5) * exp(-1.4×10^5 / (8.314 * (927 + 273))) = 2.0×10^(-5) * exp(-1.4×10^5 / (8.314 * 1200)) = 2.0×10^(-5) * exp(-14.033) ≈ 2.0×10^(-5) * 8.315×10^(-7) ≈ 1.663×10^(-11) m²/s", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出扩散系数D的具体数值，属于典型的计算题类型。 | 知识层次: 题目主要考查对扩散系数公式的直接应用和简单计算，涉及基本公式的套用和数值计算，不需要多步推理或综合分析。 | 难度: 在选择题中属于简单应用难度，题目要求直接套用扩散系数公式进行计算，涉及基本公式应用和简单计算，但不需要多个公式组合或复杂分析。", "convertible": true, "correct_option": "1.663×10^(-11) m²/s", "choice_question": "Given that for carbon diffusion in γ-Fe, D0=2.0×10^(-5)m²/s, Q=1.4×10^5J/mol, gas constant R=8.314J/(mol·K), the diffusion coefficient D at 927°C is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.663×10^(-11) m²/s", "B": "2.981×10^(-12) m²/s", "C": "3.327×10^(-11) m²/s", "D": "8.315×10^(-12) m²/s" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the Arrhenius equation D=D0*exp(-Q/RT) with T=1200K. Option B comes from incorrectly using 927K instead of 1200K, exploiting temperature unit conversion oversight. Option C doubles the correct value, targeting calculation carelessness. Option D uses R value (8.314) as the coefficient, creating a plausible-looking but physically meaningless result.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4139, "question": "The formula for yttrium iron garnet \\left(\\mathrm{Y}_{3} \\mathrm{Fe}_{3} \\mathrm{O}_{12}\\right) may be written in the form \\mathrm{Y}_{3}^{*} \\mathrm{Fe}_{2}^{*} \\mathrm{Fe}_{3}^{d} \\mathrm{O}_{12}^{2}, where the superscripts a, c, and d represent different sites on which the \\mathrm{Y}^{3+} and \\mathrm{Fe}^{3+} ions are located. The spin magnetic moments for the \\mathrm{Y}^{3+} and \\mathrm{Fe}^{\\text {out }} ions positioned in the \\mathrm{a} and C sites are oriented parallel to one another and antiparallel to the \\mathrm{Fe}^{3+} ions in \\mathrm{d} sites. Compute the number of Bohr magnetons associated with each \\mathrm{Y}^{3+} ion, given the following information: (1) each unit cell consists of eight formula \\left(\\mathrm{Y}_{3} \\mathrm{Fe}_{5} \\mathrm{O}_{12}\\right) units; (2) the unit cell is cubic with an edge length of 1.2376nm; (3) the saturation magnetization for this material is 1.0 × 10^{4} \\mathrm{~A} / m; and (4) assume that there are 5 Bohr magnetons associated with each \\mathrm{Fe}^{3+} ion.", "answer": "the number of bohr magnetons associated with each \\mathrm{y}^{3+} ion is 1.75 \\mathrm{bm}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求进行数值计算，应用给定的公式和信息来求解每个Y3+离子所关联的玻尔磁子数。解答过程涉及单位晶胞的计算、饱和磁化强度的应用以及玻尔磁子数的推导，这些都是典型的计算题特征。答案以具体数值形式给出，进一步确认了这是一个计算题。 | 知识层次: 题目需要进行多步计算，涉及饱和磁化强度、单位晶胞体积、磁矩计算等概念的综合应用，需要理解不同离子位置的磁矩取向关系，并进行数值计算。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力。 | 难度: 在选择题中属于高难度，题目涉及复杂的多步计算和多个概念的关联应用。需要理解晶体结构、磁矩计算、单位转换等知识，并进行综合分析。具体步骤包括计算单位体积内的磁矩、考虑离子排列方向、应用给定的磁化强度数据等，解题过程复杂且需要较高的计算能力。", "convertible": true, "correct_option": "1.75 bm", "choice_question": "The formula for yttrium iron garnet (Y₃Fe₅O₁₂) may be written in the form Y₃ᵃFe₂ᶜFe₃ᵈO₁₂², where the superscripts a, c, and d represent different sites on which the Y³⁺ and Fe³⁺ ions are located. The spin magnetic moments for the Y³⁺ and Fe³⁺ ions positioned in the a and c sites are oriented parallel to one another and antiparallel to the Fe³⁺ ions in d sites. Given the following information: (1) each unit cell consists of eight formula (Y₃Fe₅O₁₂) units; (2) the unit cell is cubic with an edge length of 1.2376 nm; (3) the saturation magnetization for this material is 1.0 × 10⁴ A/m; and (4) assume that there are 5 Bohr magnetons associated with each Fe³⁺ ion, the number of Bohr magnetons associated with each Y³⁺ ion is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer (1.75 bm), which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.75 bm", "B": "2.50 bm", "C": "3.25 bm", "D": "0.00 bm" }, "correct_answer": "A", "explanation": "The correct answer is A (1.75 bm) because it requires precise calculation considering the antiparallel alignment of spins and unit cell composition. Option B (2.50 bm) is designed to exploit the common mistake of averaging Fe³⁺ moments without considering Y³⁺ contribution. Option C (3.25 bm) targets those who might incorrectly assume parallel alignment of all moments. Option D (0.00 bm) is a trap for those who wrongly assume Y³⁺ has no magnetic moment due to its filled electron configuration, ignoring crystal field effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3966, "question": "The flexural strength and associated volume fraction porosity for two specimens of the same ceramic material are as follows: \begin{tabular}{cc} \\hline \\sigma_{\\mathrm{fs}} (MPa) & \\mathbf{P} \\ \\hline 100 & 0.05 \\ 50 & 0.20 \\ \\hline \\end{tabular} (b) Compute the flexural strength for a 0.10 volume fraction porosity.", "answer": "the flexural strength for a 0.10 volume fraction porosity is 79.4 mpa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的数据和公式计算特定孔隙率下的弯曲强度，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用公式进行多步计算，涉及体积分数孔隙率与弯曲强度之间的关联分析，需要一定的综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求计算特定孔隙率下的弯曲强度，涉及多步计算和概念关联，如孔隙率与强度之间的关系公式。虽然计算过程较为直接，但需要综合理解和应用相关知识，因此在选择题型内属于等级3的综合性计算问题。", "convertible": true, "correct_option": "79.4 MPa", "choice_question": "The flexural strength and associated volume fraction porosity for two specimens of the same ceramic material are as follows: \n\nσ_fs (MPa) | P \n-----------|----\n100 | 0.05 \n50 | 0.20 \n\nCompute the flexural strength for a 0.10 volume fraction porosity.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "79.4 MPa", "B": "71.6 MPa", "C": "85.2 MPa", "D": "63.8 MPa" }, "correct_answer": "A", "explanation": "正确答案A是通过正确应用孔隙率与抗弯强度的指数关系公式计算得出。干扰项B利用了对数关系而非指数关系的错误假设。干扰项C采用了线性插值的常见错误方法。干扰项D则基于孔隙率与强度成反比的过度简化假设。这些干扰项都利用了材料科学中常见的直觉判断陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1878, "question": "The viscosity corresponding to the glass transition temperature Tf is A.105dPa·s B.109dPa·s C.1011dPa·s D.1013dPa·s", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从四个选项中选择与玻璃转变温度Tf对应的粘度值，属于典型的选择题形式 | 知识层次: 题目考查对玻璃转变温度对应粘度值的记忆，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅需记忆玻璃转变温度对应的粘度值即可选出正确答案，属于基础概念的直接记忆，无需复杂理解或分析。", "convertible": true, "correct_option": "B.109dPa·s", "choice_question": "The viscosity corresponding to the glass transition temperature Tf is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The temperature where free volume disappears according to free volume theory", "B": "The temperature where configurational entropy becomes zero according to Adam-Gibbs theory", "C": "The temperature where viscosity reaches 1012 Pa·s in oxide glasses", "D": "The temperature where relaxation time reaches 100 seconds in polymer glasses" }, "correct_answer": "B", "explanation": "The correct answer is B because the glass transition temperature (Tg) is fundamentally defined by the Adam-Gibbs theory as the temperature where configurational entropy vanishes. Option A is a strong distractor because free volume theory is commonly taught but doesn't define Tg precisely. Option C exploits the common misconception that viscosity at Tg is universal, while 1012 Pa·s only applies to specific glass types. Option D targets polymer specialists by using a valid but secondary definition that doesn't apply universally to all glass formers.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 264, "question": "The diffusion activation energies of carbon, nitrogen, and hydrogen in body-centered cubic iron are 84 kJ/mol, 75 kJ/mol, and 13 kJ/mol, respectively. Analyze and explain this difference.", "answer": "The atomic radii of carbon, nitrogen, and hydrogen decrease sequentially. The smaller the atomic radius, the easier it is for the atom to diffuse through the gaps in body-centered cubic iron, and the lower the corresponding diffusion activation energy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析和解释扩散激活能的差异，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求分析不同元素在体心立方铁中扩散激活能的差异，并解释其机理。这需要综合运用原子半径、晶体结构间隙和扩散机制等知识，进行推理分析和机理解释，属于较高层次的认知能力要求。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅掌握扩散激活能的基本概念，还需要理解原子半径与晶体结构间隙之间的关系，并能将这些知识综合运用到体心立方铁的特定结构中。正确选项涉及机理层面的解释（原子半径越小越容易扩散），需要考生进行推理分析并解释现象背后的物理机制。这种在选择题中要求机理深度解释的题目，明显高于单纯记忆或简单应用的难度水平，但尚未达到需要全面分析复杂现象的最高难度（等级5）。", "convertible": true, "correct_option": "The atomic radii of carbon, nitrogen, and hydrogen decrease sequentially. The smaller the atomic radius, the easier it is for the atom to diffuse through the gaps in body-centered cubic iron, and the lower the corresponding diffusion activation energy.", "choice_question": "Why do the diffusion activation energies of carbon, nitrogen, and hydrogen in body-centered cubic iron differ (84 kJ/mol, 75 kJ/mol, and 13 kJ/mol, respectively)?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The atomic radii decrease from carbon to hydrogen, allowing easier diffusion through BCC iron's interstitial sites", "B": "The electronegativity differences with iron decrease from carbon to hydrogen, reducing bonding strength", "C": "The mass difference causes quantum tunneling effects to dominate for hydrogen diffusion", "D": "The octahedral site preference energy decreases from carbon to hydrogen in BCC lattices" }, "correct_answer": "A", "explanation": "Correct answer A reflects the actual atomic size effect where smaller atoms diffuse more easily. Option B exploits electronegativity intuition but misapplies it to diffusion. Option C introduces quantum tunneling which is irrelevant at these temperatures. Option D sounds plausible but 'octahedral site preference energy' is a fabricated concept for this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2629, "question": "Although the relative molecular mass of HF is relatively low, please explain why the boiling temperature of HF (19.4 ℃) is higher than that of HCl (-85 ℃)?", "answer": "This is because the intermolecular force in HF is hydrogen bonding, while that in HCl is van der Waals force. The bond energy of hydrogen bonding is higher than that of van der Waals force, so the boiling point of HF is higher than that of HCl.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释HF沸点高于HCl的原因，需要文字解释和论述，答案形式为简短的文字说明，而非选择、判断或计算。 | 知识层次: 题目要求解释HF和HCl沸点差异的原因，涉及氢键和范德华力的比较，需要理解分子间作用力的概念并进行分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解氢键和范德华力的概念，并能比较它们的键能差异对沸点的影响。虽然题目涉及多个概念的综合分析，但在选择题型中，正确选项直接给出了关键概念和结论，减少了推理步骤的复杂性。", "convertible": true, "correct_option": "This is because the intermolecular force in HF is hydrogen bonding, while that in HCl is van der Waals force. The bond energy of hydrogen bonding is higher than that of van der Waals force, so the boiling point of HF is higher than that of HCl.", "choice_question": "Although the relative molecular mass of HF is relatively low, why is the boiling temperature of HF (19.4 ℃) higher than that of HCl (-85 ℃)?", "conversion_reason": "The answer is a standard explanation involving intermolecular forces, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "HF forms hydrogen bonds while HCl only has dipole-dipole interactions", "B": "The higher electronegativity difference in HF leads to stronger ionic character", "C": "HF has a larger molecular surface area allowing more London dispersion forces", "D": "The smaller size of fluorine creates stronger orbital overlap in HF" }, "correct_answer": "A", "explanation": "The correct answer is A because HF exhibits hydrogen bonding (a special strong dipole-dipole interaction) while HCl only has weaker dipole-dipole interactions. Option B is incorrect because while electronegativity difference is greater in HF, it doesn't create significant ionic character. Option C is a trap as it misapplies London dispersion forces which are negligible for such small molecules. Option D incorrectly invokes orbital overlap which affects bond strength but not intermolecular forces.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4477, "question": "Compute repeat unit molecular weight for poly(ethylene terephthalate)", "answer": "192.16g/mol", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算聚对苯二甲酸乙二醇酯的重复单元分子量，需要通过数值计算和公式应用得出具体数值结果(192.16g/mol)，符合计算题的特征。 | 知识层次: 题目要求计算聚对苯二甲酸乙二醇酯的重复单元分子量，这需要应用基本的化学公式和原子量计算，属于直接套用基本知识的简单应用。 | 难度: 在选择题型中，该题目仅需直接套用已知的聚对苯二甲酸乙二醇酯重复单元分子量公式进行计算，无需额外的推导或组合多个公式。解题步骤简单直接，属于单一公式直接计算的范畴，因此在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "192.16g/mol", "choice_question": "What is the repeat unit molecular weight for poly(ethylene terephthalate)?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "192.16 g/mol", "B": "172.18 g/mol", "C": "144.13 g/mol", "D": "224.20 g/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (192.16 g/mol) which accounts for the complete repeat unit of poly(ethylene terephthalate) including both the ethylene glycol and terephthalate moieties. Option B (172.18 g/mol) is a common trap as it only considers the terephthalate unit, ignoring the ethylene glycol contribution. Option C (144.13 g/mol) exploits the misconception of counting only the aromatic ring portion. Option D (224.20 g/mol) introduces error by incorrectly adding the molecular weight of an extra ethylene unit.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 101, "question": "Both MgO (NaCl-type structure) and Li2O (anti-fluorite-type structure) are based on the cubic close packing of oxygen, and the cations are located in the interstitial sites of this arrangement. Why are Schottky defects the predominant point defects in MgO?", "answer": "Mg occupies the tetrahedral sites. The tetrahedral sites are relatively small, making it difficult for Mg ions to migrate within the lattice to form Frenkel defects. Therefore, they are more inclined to form Schottky defects (paired cation and anion vacancies).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么MgO中Schottky缺陷是主要的点缺陷，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目需要综合运用晶体结构、缺陷类型和离子迁移等知识，分析MgO中Schottky缺陷占主导的原因，涉及机理解释和推理分析。 | 难度: 在选择题型内属于最高难度等级，因为该题目要求考生：", "convertible": true, "correct_option": "Mg occupies the tetrahedral sites. The tetrahedral sites are relatively small, making it difficult for Mg ions to migrate within the lattice to form Frenkel defects. Therefore, they are more inclined to form Schottky defects (paired cation and anion vacancies).", "choice_question": "Why are Schottky defects the predominant point defects in MgO?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The octahedral site occupancy of Mg2+ creates high energy barriers for interstitial formation", "B": "The similar ionic radii of Mg2+ and O2- favor vacancy pair formation over interstitials", "C": "The high melting point of MgO thermodynamically favors Schottky defect formation", "D": "The rock salt structure inherently prevents Frenkel defects through its symmetry" }, "correct_answer": "A", "explanation": "Correct answer A addresses the key geometric constraint - Mg2+ in octahedral sites (not tetrahedral as in the original answer) creates high energy barriers for Frenkel defect formation. B is tempting as it uses a true fact (similar radii) but draws the wrong conclusion. C exploits thermodynamic intuition but incorrectly applies it. D sounds plausible with 'symmetry' but is factually incorrect about structure-property relationships.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2591, "question": "When the crystal around an edge dislocation contains vacancies below the equilibrium concentration, how will the dislocation climb?", "answer": "Negative climb", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释位错攀移的行为，需要文字论述而非选择或判断，答案\"Negative climb\"是一个简短的术语解释而非计算结果 | 知识层次: 题目要求理解空位浓度与位错攀移之间的关系，并分析在特定条件下（空位浓度低于平衡浓度）位错攀移的方向。这需要综合运用位错理论、扩散机制和热力学知识，进行推理分析和机理解释，属于较高层次的认知能力。 | 难度: 在选择题型内，该题目属于最高难度等级。理由如下：", "convertible": true, "correct_option": "Negative climb", "choice_question": "When the crystal around an edge dislocation contains vacancies below the equilibrium concentration, how will the dislocation climb?", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Negative climb", "B": "Positive climb", "C": "No climb occurs", "D": "Lateral slip" }, "correct_answer": "A", "explanation": "When vacancy concentration is below equilibrium, the dislocation absorbs vacancies to reduce their deficit, causing the extra half-plane to shrink (negative climb). Option B exploits the intuitive but incorrect assumption that vacancies always cause climb in the positive direction. Option C is a common oversimplification trap ignoring non-equilibrium conditions. Option D misdirects by introducing a completely different deformation mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4596, "question": "Briefly explain why the thermal conductivities are higher for crystalline than noncrystalline ceramics.", "answer": "Thermal conductivities are higher for crystalline than for noncrystalline ceramics because, for noncrystalline, phonon scattering, and thus the resistance to heat transport, is much more effective due to the highly disordered and irregular atomic structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释晶体陶瓷比非晶体陶瓷热导率高的原因，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释晶体和非晶体陶瓷热导率差异的原因，涉及对声子散射和原子结构无序性的理解，需要综合分析材料微观结构与热传导性能之间的关系，属于机理解释和推理分析的层次。 | 难度: 在选择题型中，该题目属于较高难度等级。正确选项不仅要求考生理解晶体和非晶体陶瓷的基本区别，还需要掌握声子散射的概念及其对热导率的影响机制。题目涉及对材料微观结构与宏观性能关系的深入理解，需要考生能够将多个物理概念（晶体结构、声子传输、热导率）联系起来进行综合分析。这种需要解释物理机理的选择题，比单纯记忆事实或简单比较的选择题难度更高，属于复杂分析层次。", "convertible": true, "correct_option": "Thermal conductivities are higher for crystalline than for noncrystalline ceramics because, for noncrystalline, phonon scattering, and thus the resistance to heat transport, is much more effective due to the highly disordered and irregular atomic structure.", "choice_question": "Why are thermal conductivities higher for crystalline than noncrystalline ceramics?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among plausible distractors in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystalline ceramics have long-range ordered atomic structures that allow efficient phonon propagation with minimal scattering", "B": "The higher density of crystalline ceramics provides more atoms per unit volume to conduct heat through electron transport", "C": "Noncrystalline ceramics have higher thermal expansion coefficients that disrupt phonon transmission pathways", "D": "Crystalline ceramics contain fewer grain boundaries that would otherwise reflect thermal vibrations" }, "correct_answer": "A", "explanation": "Correct answer A identifies the key role of phonon propagation in ordered crystalline structures. Option B is a cognitive bias trap - while density affects conductivity, ceramics primarily conduct heat through phonons not electrons. Option C exploits intuition about thermal expansion but incorrectly applies it to phonon scattering. Option D contains partial truth about grain boundaries but is misleading for amorphous materials which lack any grain structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3398, "question": "Analyze the special effects of alloying elements (such as Cr, Mo, W, etc.) on improving the thermal strength of steel", "answer": "Alloying elements (Cr, Mo, W, etc.) can increase the recrystallization temperature of steel, thereby improving its thermal strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析合金元素对钢热强度的特殊影响，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求分析合金元素（如Cr、Mo、W等）对提高钢热强度的特殊效应，这需要综合运用材料科学知识，理解合金元素对钢的再结晶温度的影响机制，并进行推理分析。这涉及到多个概念的关联和深层次的机理解释，超出了简单记忆或基本应用的范畴。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅掌握合金元素（Cr、Mo、W等）的基本作用，还需要深入理解这些元素如何通过提高钢的再结晶温度来增强热强度的机理。这涉及到对材料科学中复杂现象的全面分析，包括合金元素与钢基体之间的相互作用、热力学和动力学过程的综合理解。此外，正确选项的表述需要考生能够将多个知识点整合并进行推理分析，这在选择题型中属于对知识深度和综合运用能力要求极高的题目。", "convertible": true, "correct_option": "Alloying elements (Cr, Mo, W, etc.) can increase the recrystallization temperature of steel, thereby improving its thermal strength.", "choice_question": "Which of the following describes the effect of alloying elements (such as Cr, Mo, W, etc.) on improving the thermal strength of steel?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Alloying elements (Cr, Mo, W, etc.) can increase the recrystallization temperature of steel, thereby improving its thermal strength.", "B": "Alloying elements reduce the stacking fault energy of steel, which enhances dislocation mobility and improves thermal strength.", "C": "The primary mechanism is through increasing the elastic modulus of steel at elevated temperatures.", "D": "These elements form nano-sized precipitates that block grain boundary sliding under thermal stress." }, "correct_answer": "A", "explanation": "The correct answer is A because alloying elements like Cr, Mo, and W increase the recrystallization temperature by segregating to grain boundaries and inhibiting boundary migration. Option B is incorrect because reduced stacking fault energy would actually decrease thermal strength by facilitating dislocation movement. Option C is a common misconception - while modulus is important, it's not the primary mechanism for thermal strength improvement. Option D describes a secondary effect but not the fundamental mechanism for thermal strength enhancement in solid solution strengthened steels.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2908, "question": "What is the glass transition temperature of a polymer?", "answer": "Amorphous linear polymers can be divided into three states based on their mechanical properties at different temperatures: glassy state, high elastic state, and viscous flow state. At lower temperatures, the thermal motion of molecules is limited, preventing not only the movement of entire macromolecular chains but also the movement of chain segments or even individual chain units, causing the entire macromolecule to lose flexibility. In this state, the polymer resembles ordinary silicate glass in a supercooled liquid state, hence it is called the glassy state. The highest temperature (Tg) at which a polymer exhibits the glassy state is called the glass transition temperature, which is the temperature at which the polymer transitions from the high elastic state to the glassy state. During the glass transition, in addition to discontinuous and significant changes in mechanical properties such as the elastic modulus (E) of the polymer, other properties like the expansion coefficient, heat capacity, and dielectric constant also undergo notable changes. Therefore, the glass transition is not a thermodynamic phase transition but rather a state transition under non-equilibrium conditions, which can be regarded as a volume relaxation process. The glass transition temperature is an extremely important property of polymeric materials and serves as the dividing line between plastics and rubbers.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释玻璃化转变温度的定义和相关概念，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对玻璃化转变温度这一基本概念的定义、分类和基本原理的记忆和理解，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及了玻璃化转变温度的定义和相关概念，但正确选项提供了较为详细的解释和背景知识，帮助考生理解这一概念。题目要求考生掌握聚合物状态转变的基本原理和玻璃化转变温度的重要性，但不需要进行复杂的分析或比较多个概念。因此，在选择题型内，该题目属于等级2，即概念解释和描述的难度水平。", "convertible": true, "correct_option": "The highest temperature at which a polymer exhibits the glassy state", "choice_question": "What is the glass transition temperature (Tg) of a polymer?", "conversion_reason": "The answer provided is a standard definition of the glass transition temperature, which can be used as the correct option in a multiple-choice question. The original question can be rephrased to fit a multiple-choice format by focusing on the definition of Tg.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The highest temperature at which a polymer exhibits the glassy state", "B": "The temperature at which a polymer transitions from crystalline to amorphous state", "C": "The midpoint of the heat capacity change during the glass transition", "D": "The temperature where polymer chains achieve complete freedom of rotation" }, "correct_answer": "A", "explanation": "The correct answer is A because Tg is defined as the temperature range where a polymer transitions from a hard/glassy state to a soft/rubbery state. Option B is incorrect because Tg is unrelated to crystallinity changes (which occur at Tm). Option C is a common misconception - while DSC measurements often report the midpoint, Tg is fundamentally a state transition temperature. Option D describes the flow temperature (Tf) where viscous flow begins, not Tg.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4211, "question": "Calculate the radius of a vanadium atom, given thatV has a BCC crystal structure, a density of 5.96 \\mathrm{g} / {cm}^{3}, and an atomic weight of 50.9g / mol.", "answer": "the radius of a vanadium atom is 0.132 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解钒原子的半径，答案是一个具体的数值结果（0.132 nm），这符合计算题的特征。 | 知识层次: 题目需要多步计算和概念关联，包括BCC晶体结构的理解、密度的计算、原子半径的推导等，涉及多个知识点的综合应用，但不需要复杂的推理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构、密度与原子半径的关系，并进行多步计算。虽然题目提供了所有必要信息，但解题过程涉及单位转换、晶胞体积计算和原子半径推导，属于综合性计算问题。", "convertible": true, "correct_option": "0.132 nm", "choice_question": "What is the radius of a vanadium atom, given that V has a BCC crystal structure, a density of 5.96 g/cm³, and an atomic weight of 50.9 g/mol?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.132 nm", "B": "0.143 nm", "C": "0.122 nm", "D": "0.154 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.132 nm) calculated using the BCC unit cell relationship (4r = √3a) combined with density formula. B (0.143 nm) mimics FCC structure radius, exploiting crystal structure confusion. C (0.122 nm) uses incorrect atomic packing factor for BCC. D (0.154 nm) is the nearest neighbor distance in BCC, not atomic radius, targeting unit cell geometry misunderstanding.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2827, "question": "Determine the engineering strain εe and true strain εT when the length increases from L to 1.1L, and explain which one better reflects the true deformation characteristics", "answer": "εe = (1.1 - 1)L / L = 10%; εT = ln(1.1L / L) = 9.5%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（工程应变和真实应变）并应用相关公式，答案以计算结果形式呈现 | 知识层次: 题目主要涉及工程应变和真实应变的基本公式应用和简单计算，不需要多步计算或综合分析，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要计算工程应变和真实应变，但两者都是直接套用基本公式（工程应变εe = ΔL/L，真实应变εT = ln(Lf/L0)），且计算过程简单。题目仅要求对两种应变进行基本计算和简单比较，不涉及复杂推导或多步骤分析，因此在选择题型内属于等级2难度。", "convertible": true, "correct_option": "εe = 10%; εT = 9.5%", "choice_question": "When the length increases from L to 1.1L, what are the engineering strain εe and true strain εT?", "conversion_reason": "The calculation has a definite answer that can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "εe = 10%; εT = 9.5%", "B": "εe = 10%; εT = ln(1.1)", "C": "εe = 0.1; εT = 0.095", "D": "εe = ΔL/L0; εT = ln(λ)" }, "correct_answer": "A", "explanation": "正确答案A直接给出了工程应变和真实应变的数值计算结果。B选项利用真实应变公式ln(1.1)的数学表达形式制造干扰，虽然数学正确但不符合题目要求的百分比形式。C选项数值正确但混淆了小数和百分比的表达方式。D选项给出了通用公式而非具体计算结果，利用定义式制造干扰。先进AI可能被B选项的数学严谨性或D选项的通用性所迷惑而忽略题目要求的数值结果。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4605, "question": "Explain the two sources of magnetic moments for electrons.", "answer": "The two sources of magnetic moments for electrons are the electron's orbital motion around the nucleus, and also, its spin.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释电子磁矩的两个来源，需要文字解释和论述，答案也是以文字形式呈现的简要说明。 | 知识层次: 题目考查对电子磁矩来源的基本概念记忆和理解，仅需回答轨道运动和自旋两个基本来源，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆和识别电子磁矩的两个基本来源（轨道运动和自旋），属于基础概念的直接回忆，无需解释或分析步骤，因此属于最低难度等级。", "convertible": true, "correct_option": "The two sources of magnetic moments for electrons are the electron's orbital motion around the nucleus, and also, its spin.", "choice_question": "Which of the following correctly describes the two sources of magnetic moments for electrons?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Orbital motion and spin", "B": "Nuclear spin and electron charge", "C": "Lattice vibrations and spin-orbit coupling", "D": "Phonon interactions and orbital angular momentum" }, "correct_answer": "A", "explanation": "The correct answer is A because the two fundamental sources of magnetic moments for electrons are indeed their orbital motion around the nucleus and their intrinsic spin. Option B is incorrect because while electron charge is relevant, nuclear spin does not contribute to the electron's magnetic moment. Option C uses plausible material science concepts (lattice vibrations and spin-orbit coupling) that are related but not the fundamental sources. Option D similarly distracts with real but irrelevant phenomena in this context (phonon interactions). Both C and D exploit the cognitive bias of using advanced material science terminology that seems relevant but isn't.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3413, "question": "Explain the meaning of the steel grade T12A", "answer": "T12A is a carbon tool steel, wc=1.2% high-grade quality steel", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释钢号T12A的含义，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对钢材牌号T12A的基本定义和分类的记忆，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆并复述T12A钢的基本定义和成分（碳工具钢，含碳量1.2%的高质量钢），属于最基础的概念记忆层次。不需要进行概念解释或复杂体系阐述，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "T12A is a carbon tool steel, wc=1.2% high-grade quality steel", "choice_question": "Which of the following best describes the meaning of the steel grade T12A?", "conversion_reason": "The answer is a standard definition or description, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "T12A is a carbon tool steel, wc=1.2% high-grade quality steel", "B": "T12A is a titanium alloy with 12% aluminum content", "C": "T12A is a stainless steel grade with 12% chromium content", "D": "T12A is a structural steel with tensile strength of 1200 MPa" }, "correct_answer": "A", "explanation": "The correct answer is A because T12A follows the Chinese GB standard for carbon tool steels where 'T' denotes carbon tool steel, '12' indicates 1.2% carbon content, and 'A' signifies high-grade quality. Option B exploits the 'T' prefix which could be misassociated with titanium alloys. Option C creates confusion with stainless steel grading systems where numbers often indicate chromium percentage. Option D plays on the numerical similarity between the grade designation and mechanical properties, a common source of misclassification in material standards.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1475, "question": "In the vertical section of a ternary phase diagram, the lever rule cannot be used to determine the mass fractions of the three equilibrium phases.", "answer": "Correct", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（Correct），符合判断题的特征。题目没有提供多个选项，也不需要计算或文字解释，只需判断陈述的对错。 | 知识层次: 题目考查对三元相图中杠杆规则应用范围的基础概念记忆，仅需判断陈述是否正确，不涉及复杂分析或计算。 | 难度: 该题目属于基础概念正误判断，仅需记忆三元相图中杠杆规则的应用限制即可作答，无需深入理解或分析多个概念。在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "Correct", "choice_question": "In the vertical section of a ternary phase diagram, the lever rule cannot be used to determine the mass fractions of the three equilibrium phases.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The Hall-Petch relationship holds true for all polycrystalline materials regardless of grain size range.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "The Hall-Petch relationship describes how yield strength increases with decreasing grain size, but this relationship breaks down at extremely small grain sizes (typically below 10-20 nm) where inverse Hall-Petch behavior may occur due to grain boundary sliding becoming dominant.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4151, "question": "Match the type of light transmission with its description: Transmits light with relative little absorption.", "answer": "A transparent material transmits light with relatively little absorption.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求匹配光的传输类型与其描述，并给出了一个具体的描述例子。虽然看起来像匹配题，但答案是以完整的句子形式给出的解释，类似于简答题需要文字解释和论述的形式。 | 知识层次: 题目考查对透明材料基本定义和特性的记忆和理解，属于基础概念记忆范畴。 | 难度: 在选择题型中，此题仅要求识别基本定义（透明材料的特性），属于最基础的概念记忆层面。题目直接给出定义描述与正确选项的对应关系，无需任何分析或推理步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "A transparent material transmits light with relatively little absorption.", "choice_question": "Which of the following materials transmits light with relatively little absorption?", "conversion_reason": "The original short answer question can be converted into a multiple-choice format by rephrasing the question to ask for the correct description of light transmission and providing the original answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Single crystal sapphire at 1550nm wavelength", "B": "Polycrystalline alumina with 99.9% purity", "C": "Amorphous silica glass with OH content <1ppm", "D": "Hot-pressed spinel (MgAl2O4) with 99.5% density" }, "correct_answer": "A", "explanation": "Single crystal sapphire has exceptionally low absorption at 1550nm due to its perfect crystalline structure and wide bandgap. Polycrystalline alumina (B) has grain boundary scattering. Silica glass (C), while transparent, has intrinsic vibrational absorption bands near 1550nm. Hot-pressed spinel (D) contains residual porosity causing light scattering. The question exploits AI's tendency to overestimate the transparency of amorphous materials and underestimate crystalline perfection effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1634, "question": "The adsorption occurring on the surface of solids can be divided into two types: (15) and (16).", "answer": "(15) Physical adsorption; (16) Chemical adsorption", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个空缺处的答案，需要根据知识进行文字回答，而不是选择、判断或计算 | 知识层次: 题目考查对固体表面吸附类型的基本分类记忆，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆固体表面吸附的两种基本类型（物理吸附和化学吸附），属于基础概念记忆，无需解释或复杂分析。题目直接给出正确选项，考察的是对基础定义的简单回忆，因此属于等级1难度。", "convertible": true, "correct_option": "Physical adsorption and Chemical adsorption", "choice_question": "The adsorption occurring on the surface of solids can be divided into which two types?", "conversion_reason": "The original short answer question asks for two standard terms (Physical adsorption and Chemical adsorption), which can be converted into a multiple-choice question format by listing these terms as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Physical adsorption and Chemisorption", "B": "Physisorption and Chemical bonding", "C": "Surface adsorption and Bulk absorption", "D": "Van der Waals adsorption and Covalent adsorption" }, "correct_answer": "A", "explanation": "The correct answer is A because adsorption is fundamentally classified into physical adsorption (physisorption) involving weak van der Waals forces, and chemical adsorption (chemisorption) involving stronger chemical bonds. Option B incorrectly pairs 'physisorption' with 'chemical bonding' which are not parallel classification terms. Option C confuses surface phenomena with bulk material behavior. Option D uses correct force types but misrepresents them as adsorption classifications, creating a technical terminology trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4683, "question": "(a) Determine the ratio of butadiene to acrylonitrile repeat units in a copolymer having a number-average molecular weight of 250,000 g/mol and a degree of polymerization of 4640.", "answer": "the ratio of butadiene to acrylonitrile repeat units in the copolymer is fb/fa = 4.0.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定共聚物中丁二烯和丙烯腈重复单元的比例，答案是一个具体的数值结果（fb/fa = 4.0），这表明解答过程涉及计算步骤。 | 知识层次: 题目需要多步计算和概念关联，包括分子量计算、重复单元比例确定以及聚合度应用，涉及综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解共聚物组成与分子量之间的关系，进行多步计算（包括分子量计算和比例求解），并正确关联聚合度与重复单元数的概念。虽然题目提供了正确选项，但解题过程涉及多个化学概念的整合和计算步骤的综合运用。", "convertible": true, "correct_option": "fb/fa = 4.0", "choice_question": "Determine the ratio of butadiene to acrylonitrile repeat units in a copolymer having a number-average molecular weight of 250,000 g/mol and a degree of polymerization of 4640. The ratio is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "fb/fa = 4.0", "B": "fb/fa = 2.5", "C": "fb/fa = 3.2", "D": "fb/fa = 1.6" }, "correct_answer": "A", "explanation": "正确答案A通过计算单体分子量和重复单元数得出正确比例。干扰项B利用常见误算的分子量比值，C模拟忽略单体质量差异的错误，D则基于对聚合度概念的误解。这些干扰项专门针对AI在材料科学计算中容易犯的直觉性错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 57, "question": "What type of silicate structure does Mg2[SiO4] belong to?", "answer": "Island", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释Mg2[SiO4]属于哪种硅酸盐结构，答案需要文字描述（\"Island\"），而不是从选项中选择或简单判断对错，也不需要计算。 | 知识层次: 题目考查对硅酸盐结构分类的基本概念记忆和理解，只需识别Mg2[SiO4]属于孤岛状硅酸盐结构，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目仅要求识别Mg2[SiO4]所属的硅酸盐结构类型，属于基础概念记忆层次。正确选项\"Island\"是硅酸盐结构分类中最基本的一种，无需复杂推理或概念比较，只需直接回忆相关定义即可作答。", "convertible": true, "correct_option": "Island", "choice_question": "What type of silicate structure does Mg2[SiO4] belong to?", "conversion_reason": "The answer is a standard term in geology, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Island", "B": "Chain", "C": "Sheet", "D": "Framework" }, "correct_answer": "A", "explanation": "The correct answer is A (Island) because Mg2[SiO4] consists of isolated [SiO4] tetrahedra not sharing oxygen atoms. Option B (Chain) exploits the common misconception that silicates tend to form extended structures. Option C (Sheet) is designed to mislead by suggesting a layered structure common in phyllosilicates. Option D (Framework) targets the intuition that 3D connectivity is typical in silicate minerals like quartz.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1347, "question": "Briefly describe the fourth essential reason for the high hardness of martensite: the transformation strengthening mechanism", "answer": "During martensitic transformation, substructures with high lattice defect density are created within the crystal. The high-density dislocation networks in lath martensite and the fine twins in plate martensite both hinder dislocation motion, thereby causing strengthening through transformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要描述马氏体高硬度的第四个重要原因，即转变强化机制，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释马氏体高硬度的第四个重要原因——相变强化机制，涉及对马氏体相变过程中亚结构形成及其对位错运动阻碍作用的深入理解。需要综合运用晶体缺陷、相变机制和强化机理等多方面知识进行机理分析和解释，思维过程具有较高的深度要求。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅要理解马氏体高硬度的基本概念，还需要深入掌握马氏体转变过程中产生的亚结构（高位错密度的板条马氏体和含细密孪晶的片状马氏体）及其对位错运动的阻碍机制。这涉及到晶体缺陷、位错理论、相变强化等多个复杂概念的整合运用，需要考生具备将微观结构与宏观性能关联起来的综合分析能力。在选择题型中，这种需要多维度知识整合和机理深度解释的题目属于最复杂的考查类型。", "convertible": true, "correct_option": "During martensitic transformation, substructures with high lattice defect density are created within the crystal. The high-density dislocation networks in lath martensite and the fine twins in plate martensite both hinder dislocation motion, thereby causing strengthening through transformation.", "choice_question": "Which of the following describes the fourth essential reason for the high hardness of martensite: the transformation strengthening mechanism?", "conversion_reason": "The answer is a standard explanation that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The high hardness is primarily due to the formation of fine twins in plate martensite that act as barriers to dislocation motion", "B": "The transformation creates a supersaturated solid solution where solute atoms pin dislocations through Cottrell atmospheres", "C": "The rapid quenching process introduces residual compressive stresses that enhance hardness through stress hardening", "D": "The body-centered tetragonal structure of martensite inherently has higher Peierls stress than austenite" }, "correct_answer": "A", "explanation": "Option A correctly identifies the transformation-induced substructures (twins in plate martensite) as the key strengthening mechanism. Option B describes solid solution strengthening, which is secondary. Option C confuses transformation hardening with residual stress effects. Option D incorrectly attributes hardness to crystal structure rather than transformation-induced defects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3661, "question": "Suppose one Schottky defect is present in every tenth unit cell of MgO. MgO has the sodium chloride crystal structure and a lattice parameter of 0.396 nm. Calculate the density of the ceramic.", "answer": "4.205 g/cm^3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解MgO陶瓷的密度，答案是一个具体的数值（4.205 g/cm^3），这符合计算题的特征。 | 知识层次: 题目需要多步计算和概念关联，包括理解Schottky缺陷的概念、MgO的晶体结构、晶格参数的应用以及密度的计算公式。虽然不涉及复杂的推理分析或机理解释，但需要综合运用多个知识点进行计算。 | 难度: 在选择题中属于中等偏上难度，需要理解Schottky缺陷的概念、晶格参数与密度的关系，并进行多步计算。虽然题目给出了正确选项，但解题过程涉及单位换算、缺陷浓度计算和密度公式的综合应用，对学生的概念掌握和计算能力要求较高。", "convertible": true, "correct_option": "4.205 g/cm^3", "choice_question": "Suppose one Schottky defect is present in every tenth unit cell of MgO. MgO has the sodium chloride crystal structure and a lattice parameter of 0.396 nm. The density of the ceramic is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.205 g/cm^3", "B": "3.978 g/cm^3", "C": "4.512 g/cm^3", "D": "3.650 g/cm^3" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算考虑Schottky缺陷后的实际密度得到的。干扰项B是忽略缺陷直接计算的完美晶体密度，利用了AI可能忽略缺陷影响的认知偏差。干扰项C是错误地将氧空位视为主要缺陷类型计算的结果，利用了材料缺陷类型的直觉陷阱。干扰项D是错误使用摩尔体积计算的结果，设置了单位转换和计算步骤的多层次验证陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3180, "question": "Explain the concept of dynamic undercooling", "answer": "During crystal growth, a certain degree of undercooling in the liquid ahead of the solid/liquid interface is required to satisfy (dN/dt)F > (dN/dt)M. This undercooling is called dynamic undercooling (ΔTc = Tm − Ti), which is a necessary condition for crystal growth.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释动态过冷的概念，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查动态过冷的基本定义和原理，属于基础概念的记忆和理解范畴 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但要求考生不仅要记住动态过冷的定义，还需要理解其背后的物理意义（即晶体生长过程中液体/固体界面前沿所需的过冷度条件）。这超出了简单的定义复述，属于概念解释和描述的层次。不过题目并未要求考生分析复杂概念体系或进行多步骤推导，因此难度未达到等级3。", "convertible": true, "correct_option": "During crystal growth, a certain degree of undercooling in the liquid ahead of the solid/liquid interface is required to satisfy (dN/dt)F > (dN/dt)M. This undercooling is called dynamic undercooling (ΔTc = Tm − Ti), which is a necessary condition for crystal growth.", "choice_question": "Which of the following best describes the concept of dynamic undercooling?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "During crystal growth, a certain degree of undercooling in the liquid ahead of the solid/liquid interface is required to satisfy (dN/dt)F > (dN/dt)M. This undercooling is called dynamic undercooling (ΔTc = Tm − Ti), which is a necessary condition for crystal growth.", "B": "The minimum temperature difference required to initiate solidification in a supercooled liquid, calculated as the difference between the melting point and the temperature at which nucleation first occurs.", "C": "The additional undercooling needed to overcome the kinetic barrier at the solid-liquid interface during rapid solidification processes.", "D": "The temperature difference between the theoretical melting point and the actual solidification temperature when considering only thermodynamic factors, excluding kinetic effects." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines dynamic undercooling as the undercooling required at the solid/liquid interface for crystal growth. Option B describes nucleation undercooling, a common confusion point. Option C mixes concepts by introducing rapid solidification kinetics, which is a different phenomenon. Option D incorrectly excludes kinetic effects, which are fundamental to dynamic undercooling. The distractors exploit common misconceptions between different types of undercooling in solidification theory.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2128, "question": "Can it be said that there is actually only one diffusion law, not two?", "answer": "Yes. Because the second law of diffusion is derived from the first law of diffusion, and the second law of diffusion is a continuity equation established based on the continuity of matter, namely $$\\\\frac{\\\\partial c}{\\\\partial t}=-\\\\frac{\\\\partial J}{\\\\partial x}$$ If $J=-D\\\\frac{\\\\partial\\\\epsilon}{\\\\partial x}$ is substituted into the above equation, then $$\\\\frac{\\\\partial c}{\\\\partial t}=\\\\frac{\\\\partial}{\\\\partial x}\\\\Big(D\\\\frac{\\\\partial c}{\\\\partial x}\\\\Big)$$ This is the second law of diffusion. It represents the relationship of $c=f(\\\\boldsymbol{x},t)$, and its practical scope includes steady-state diffusion and non-steady-state diffusion, hence it is a universal diffusion formula. Additionally, in the formula =D, if the steady-state condition is substituted, i.e., =0, then D must be a constant, and this result is the first law, where the constant is J. $$\\\\Delta c/\\\\Delta x=9.1\\\\times10^{-3}~\\\\mathrm{mol/m^{4}};\\\\quad(2)~\\\\delta=3.3\\\\times10^{-4}~\\\\mathrm{m}_{\\\\circ}$$", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对“是否可以说实际上只有一个扩散定律而不是两个”进行解释和论述，答案提供了详细的文字解释和数学推导，符合简答题的特征。 | 知识层次: 题目要求对扩散定律进行深入分析和推理，涉及第一和第二扩散定律的数学推导和物理意义的解释，需要综合运用扩散理论的知识，理解定律之间的内在联系和适用范围，属于复杂分析和机理解释的层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求深入理解扩散定律的推导过程，并能够综合运用第一和第二扩散定律进行推理分析。解题步骤涉及复杂的数学推导和物理概念的综合运用，需要考生具备扎实的理论基础和较高的逻辑思维能力。此外，题目还要求考生能够从稳态和非稳态扩散的角度进行机理解释，这进一步增加了题目的复杂性和难度。因此，在选择题型内，该题目属于复杂现象全面分析的难度等级。", "convertible": true, "correct_option": "Yes. Because the second law of diffusion is derived from the first law of diffusion, and the second law of diffusion is a continuity equation established based on the continuity of matter.", "choice_question": "Can it be said that there is actually only one diffusion law, not two?", "conversion_reason": "The answer is a clear and concise statement that can serve as a correct option in a multiple-choice format. The question itself is already in a form that can be directly used as a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because the second law is just a continuity equation derived from the first law's conservation principle", "B": "No, because the first law describes steady-state diffusion while the second law describes non-steady-state diffusion", "C": "No, because the first law applies to metals while the second law applies to ceramics", "D": "Yes, because both laws can be unified under the general transport theorem for all materials" }, "correct_answer": "A", "explanation": "The correct answer is A because Fick's second law is indeed derived from combining Fick's first law with the continuity equation. Option B is a cognitive bias trap - while the laws describe different conditions, this doesn't make them fundamentally separate. Option C exploits material-specific misconceptions - both laws apply universally. Option D sounds sophisticated but incorrectly suggests the unification requires additional transport theorems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3105, "question": "High elastic alloys have (1). A. high elastic limit and high elastic modulus B. high elastic limit and low elastic modulus C. low elastic limit and high elastic modulus D. low elastic limit and low elastic modulus", "answer": "(1)B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项A、B、C、D中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查对高弹性合金基本特性的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然题目涉及高弹性合金的两个关键特性（弹性极限和弹性模量），但选项设计相对直接，只需理解高弹性合金的基本定义即可选出正确答案。不需要复杂的分析或多个概念的交叉比较，属于概念理解和简单辨析的层次。", "convertible": true, "correct_option": "B. high elastic limit and low elastic modulus", "choice_question": "High elastic alloys have:", "conversion_reason": "原题目已经是选择题（multiple_choice）格式，且选项明确，可以直接转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High stacking fault energy and low Peierls stress", "B": "Low stacking fault energy and high Peierls stress", "C": "High stacking fault energy and high Peierls stress", "D": "Low stacking fault energy and low Peierls stress" }, "correct_answer": "A", "explanation": "High elastic alloys require high stacking fault energy to facilitate dislocation movement and low Peierls stress to enable easy dislocation glide. Option B reverses both key parameters, creating a direct opposite trap. Option C combines two high-value parameters that would actually hinder elasticity. Option D creates a plausible but incorrect combination that would lead to poor elastic recovery. The correct combination (A) requires understanding the competing effects of these two parameters on dislocation dynamics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2490, "question": "Calculate the length of the [11 0] crystal direction in a hexagonal crystal (in units of lattice constants a and c)", "answer": "The formula for the length of the [11 0] crystal direction in a hexagonal crystal: L = a√3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算六方晶体中[11 0]晶向的长度，需要使用特定的公式进行数值计算，答案给出了具体的计算公式和结果形式。 | 知识层次: 题目要求应用基本公式计算六方晶体中[11 0]方向的长度，属于直接套用公式的简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需直接套用单一公式（L = a√3）进行计算，无需额外的公式组合或复杂推导。属于最基础的公式应用级别，符合等级1的单一公式直接计算标准。", "convertible": true, "correct_option": "L = a√3", "choice_question": "What is the length of the [11 0] crystal direction in a hexagonal crystal (in units of lattice constants a and c)?", "conversion_reason": "The answer is a specific formula, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "a√3", "B": "a√(3/4 + (c/a)^2)", "C": "a√(1 + (c/a)^2)", "D": "2a" }, "correct_answer": "A", "explanation": "The correct answer is A because in hexagonal crystals, the [11 0] direction lies entirely in the basal plane and its length is simply a√3 in terms of the lattice constant a. Option B is a cognitive bias trap that incorrectly incorporates the c/a ratio which is irrelevant for basal plane directions. Option C exploits the common mistake of applying cubic crystal direction length formulas to hexagonal systems. Option D is a professional intuition trap that seems plausible for certain high-symmetry directions but is incorrect for [11 0].", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1697, "question": "Given: When the grain size of annealed pure iron is 16 per mm², the yield strength σₛ = 100 MPa. When the grain size is 4096 per mm², σₛ = 250 MPa. Find the value of yield strength σₛ when the grain size is 256 per mm².", "answer": "According to the Hall-Petch formula, σₛ = σ₀ + Kd⁻¹ᐟ², the yield strength σₛ of the material is calculated from the average grain size d. The grain size is represented by the radius of an equal-area circle, i.e., d₁ = (4A₁/π)¹ᐟ², d₂ = (4A₂/π)¹ᐟ², where A₁ and A₂ are the grain areas. Thus, σₛ₁ = σ₀ + Kd₁⁻¹ᐟ², σₛ₂ = σ₀ + Kd₂⁻¹ᐟ². Given A₁ = 1/16 mm², A₂ = 1/4096 mm², σₛ₁ = 100 MPa, σₛ₂ = 250 MPa, we find K = 25√2 π⁻¹ᐟ⁴ MPa·mm¹ᐟ², σ₀ = 50 MPa. Then, with A₃ = 1/256 mm², we find σₛ₃ = 150 MPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求根据给定的数据和公式（Hall-Petch公式）进行计算，最终得出一个具体的数值结果（150 MPa）。解答过程涉及数值计算和公式应用，符合计算题的特征。 | 知识层次: 题目需要应用Hall-Petch公式进行多步计算，涉及不同晶粒尺寸下的屈服强度计算，需要理解公式中各参数的含义并进行数值求解。虽然计算过程较为直接，但需要一定的综合分析能力和公式应用技巧。 | 难度: 在选择题中属于中等偏上难度，需要理解Hall-Petch公式并正确应用，涉及多步计算和单位转换。虽然题目提供了关键公式和部分参数，但需要考生自行推导K值和σ₀值，并最终计算出新的屈服强度。这要求对材料科学中的晶粒尺寸与力学性能关系有较好的理解，并能进行综合计算分析。", "convertible": true, "correct_option": "150 MPa", "choice_question": "Given: When the grain size of annealed pure iron is 16 per mm², the yield strength σₛ = 100 MPa. When the grain size is 4096 per mm², σₛ = 250 MPa. What is the value of yield strength σₛ when the grain size is 256 per mm²?", "conversion_reason": "The calculation problem has a definite numerical answer (150 MPa), which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "150 MPa", "B": "175 MPa", "C": "200 MPa", "D": "125 MPa" }, "correct_answer": "A", "explanation": "The correct answer is derived from the Hall-Petch relationship (σₛ = σ₀ + k/√d), where grain size and yield strength follow a square root relationship. Calculating with given data points shows σₛ = 150 MPa at 256 grains/mm². Option B is a linear interpolation trap exploiting cognitive bias. Option C mimics a quadratic relationship misconception. Option D reverses the strength-grain size relationship, a common intuition error in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 645, "question": "Reaction diffusion", "answer": "Reaction diffusion: The diffusion accompanied by chemical reactions that leads to the formation of new phases is called reaction diffusion. For example, when infiltrating elements diffuse from the metal surface into the interior and their concentration exceeds the solubility limit, new phases appear.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Reaction diffusion\"进行文字解释和论述，答案提供了详细的定义和例子，符合简答题的特征。 | 知识层次: 题目考查对反应扩散这一基本概念的定义和简单例子的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及反应扩散的定义和基本原理，但正确选项提供了明确的解释和示例，使得学生可以通过记忆和理解基础概念来回答。不需要复杂的分析或比较多个概念，但需要一定的概念理解和描述能力。", "convertible": true, "correct_option": "The diffusion accompanied by chemical reactions that leads to the formation of new phases is called reaction diffusion. For example, when infiltrating elements diffuse from the metal surface into the interior and their concentration exceeds the solubility limit, new phases appear.", "choice_question": "Which of the following best describes reaction diffusion?", "conversion_reason": "The answer is a standard definition and explanation of the term 'reaction diffusion', which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diffusion accompanied by chemical reactions that leads to the formation of new phases", "B": "The simultaneous diffusion of multiple species leading to concentration gradient relaxation without phase changes", "C": "A special case of Fick's second law where reaction terms are included in the diffusion equation", "D": "The process where diffusion rates are enhanced by catalytic surface reactions" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines reaction diffusion as involving new phase formation through combined diffusion and chemical reactions. Option B is a cognitive bias trap describing interdiffusion without phase changes. Option C exploits technical intuition by referencing a mathematically plausible but incomplete definition. Option D creates a multi-level verification trap by mixing correct elements (surface reactions) in wrong context (catalytic enhancement).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4005, "question": "A plate of an alloy steel has a plane-strain fracture toughness of 50 MPa·{m}^{1 / 2}. If it is known that the largest surface crack is 0.5mm long, and that the value of Y is 1.1 , which of the following can be said about this plate when a tensile stress of 1200 MPa is applied?(a) The plate will definitely fracture.(b) The plate will definitely not fracture. c) It is not possible to determine whether or not the plate will fracture.", "answer": "the plate will definitely fracture.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（a）、（b）、（c）中选择正确答案，符合选择题的特征。 | 知识层次: 题目主要考查对断裂韧性公式的直接应用，涉及基本公式的套用和简单计算，不需要复杂的分析或推理过程。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接套用基本公式（断裂韧性公式）并进行简单计算即可得出答案。解题步骤明确且直接，无需公式变形或多步骤推理，符合等级2的简单公式选择和应用标准。", "convertible": true, "correct_option": "a) The plate will definitely fracture.", "choice_question": "A plate of an alloy steel has a plane-strain fracture toughness of 50 MPa·{m}^{1 / 2}. If it is known that the largest surface crack is 0.5mm long, and that the value of Y is 1.1 , which of the following can be said about this plate when a tensile stress of 1200 MPa is applied?", "conversion_reason": "The original question is already in a multiple-choice format with distinct options and a clear correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The plate will fracture due to exceeding the critical stress intensity factor", "B": "The plate will not fracture because the applied stress is below the yield strength", "C": "The plate will undergo plastic deformation but not fracture", "D": "The fracture behavior cannot be determined without knowing the fatigue limit" }, "correct_answer": "A", "explanation": "The correct answer is A because the calculated stress intensity factor (K_I = Yσ√(πa) = 1.1×1200×√(π×0.0005) ≈ 52.3 MPa·m^{1/2}) exceeds the given fracture toughness (50 MPa·m^{1/2}). Option B is a cognitive bias trap that misleads by focusing on yield strength instead of fracture mechanics. Option C exploits the common misconception that plastic deformation prevents fracture. Option D introduces an irrelevant fatigue parameter to confuse systems that don't fully grasp fracture mechanics principles.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4209, "question": "Iron has a BCC crystal structure, an atomic radius of 0.124nm, and an atomic weight of 55.85g / mol. Compute and compare its theoretical density with the experimental value found inside the front cover.", "answer": "the theoretical density of iron is 7.90g / {cm}^{3}. the experimental value given inside the front cover is 7.87g / {cm}^{3}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铁的理論密度，并与实验值进行比较。答案给出了具体的计算结果，符合计算题的特征。 | 知识层次: 题目主要考查对BCC晶体结构密度计算公式的直接应用，涉及原子半径、原子质量和单位换算等基本参数的使用，计算过程较为直接，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用BCC晶体结构的密度计算公式，但计算步骤相对直接，仅需套用原子半径、原子量和晶格常数之间的关系公式即可得出理论密度，并与给定实验值进行简单比较。不需要复杂的推导或多步骤计算，因此属于等级2难度。", "convertible": true, "correct_option": "7.90g/cm³", "choice_question": "Iron has a BCC crystal structure, an atomic radius of 0.124nm, and an atomic weight of 55.85g/mol. What is the theoretical density of iron?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.90 g/cm³", "B": "8.57 g/cm³", "C": "7.87 g/cm³", "D": "8.90 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer is A (7.90 g/cm³) calculated using the BCC unit cell volume and atomic mass. Option B (8.57 g/cm³) is a trap for those who mistakenly use FCC packing factor. Option C (7.87 g/cm³) is the experimental value that appears deceptively close. Option D (8.90 g/cm³) exploits confusion with nickel's density, a common reference metal.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 512, "question": "What are the main influencing factors of constitutional supercooling?", "answer": "The main influencing factors of constitutional supercooling include: melt cooling rate, impurity concentration C0, partition coefficient k0, diffusion coefficient D, growth rate R, and temperature gradient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述影响成分过冷的主要因素，答案提供了详细的文字解释和列举了多个影响因素，符合简答题的特征。 | 知识层次: 题目要求列举并解释影响成分过冷的主要因素，涉及多个参数的关联和综合分析，需要理解各因素之间的相互作用及其对成分过冷的影响机制，属于中等应用层次。 | 难度: 在选择题中属于中等难度，题目要求考生理解并综合多个概念（如冷却速率、杂质浓度、分配系数等）来分析影响成分过冷的主要因素。虽然不需要进行复杂的计算，但需要对材料科学中的基本概念有较深的理解和关联能力。", "convertible": true, "correct_option": "melt cooling rate, impurity concentration C0, partition coefficient k0, diffusion coefficient D, growth rate R, and temperature gradient", "choice_question": "Which of the following are the main influencing factors of constitutional supercooling?", "conversion_reason": "The answer is a standard list of factors, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "melt cooling rate, impurity concentration C0, partition coefficient k0, diffusion coefficient D, growth rate R, and temperature gradient", "B": "cooling rate, solute concentration, elastic modulus, viscosity coefficient, and thermal expansion coefficient", "C": "partition coefficient k0, diffusion coefficient D, growth rate R, thermal conductivity, and specific heat capacity", "D": "impurity concentration C0, growth rate R, temperature gradient, Young's modulus, and Poisson's ratio" }, "correct_answer": "A", "explanation": "The correct answer A includes all the key parameters governing constitutional supercooling as defined by Tiller's criterion. Option B introduces mechanical properties (elastic modulus) and transport properties (viscosity) that are irrelevant to solute redistribution. Option C substitutes critical thermal parameters (temperature gradient) with general material properties (thermal conductivity). Option D similarly mixes mechanical properties (Young's modulus) with solidification parameters, creating a plausible-looking but fundamentally incorrect combination. These distractors exploit AI's tendency to associate broad material properties with complex phenomena without rigorous parameter validation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4844, "question": "Predict whether Sulfur (S) will act as a donor or an acceptor when added to Indium Antimonide (InSb). Assume that the impurity elements are substitutional.", "answer": "Sulfur will act as a donor in InSb. Since S is from group VIA of the periodic table, it will substitute for Sb; an S atom has one more valence electron than an Sb atom.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求预测硫在锑化铟中的行为并解释原因，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要理解元素在半导体中的掺杂行为，涉及元素周期表族数的知识，并需要将这一知识应用到具体的半导体材料InSb中。虽然不需要复杂的计算或多步骤推理，但需要对概念进行关联和综合分析，以判断硫在InSb中的掺杂类型。 | 难度: 在选择题中属于中等难度，需要理解半导体掺杂原理、元素周期表分组特性以及替代性杂质行为等概念，并进行综合分析判断硫在InSb中的掺杂行为。虽然不需要多步计算，但需要将多个知识点关联起来才能正确解答。", "convertible": true, "correct_option": "Sulfur will act as a donor in InSb.", "choice_question": "Predict whether Sulfur (S) will act as a donor or an acceptor when added to Indium Antimonide (InSb). Assume that the impurity elements are substitutional.", "conversion_reason": "The answer is a standard concept in material science, and the question can be converted into a multiple-choice format by providing options such as 'donor', 'acceptor', or 'neither'.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Donor (n-type)", "B": "Acceptor (p-type)", "C": "Amphoteric (both donor and acceptor)", "D": "Neutral (no doping effect)" }, "correct_answer": "A", "explanation": "Sulfur has 6 valence electrons, while antimony (Sb) has 5. When S substitutes Sb in InSb, it provides one extra electron, acting as a donor (n-type dopant). Option B is incorrect but tempting because S is in group VI like oxygen which can sometimes show acceptor behavior. Option C exploits the rare case of amphoteric behavior seen in some impurities. Option D is a trap for those who might think the extra electron gets trapped in a deep level.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3394, "question": "The bolts on the gear hobbing machine should have been made of 45 steel, but T12 steel was mistakenly used instead, and the quenching process for 45 steel was still applied. What microstructure will be obtained in this case? What will the properties be like?", "answer": "Quenching: The microstructure will consist of martensite, a significant amount of retained austenite, and a small amount of carbide. Properties: Martensite is hard and brittle, retained austenite has low hardness, resulting in non-uniform properties.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释在特定条件下（错误使用T12钢并应用45钢的淬火工艺）会得到何种微观结构及其性能特点，答案需要详细的文字描述和论述，而非选择、判断或计算。 | 知识层次: 题目要求分析不同钢材在错误热处理工艺下的显微组织和性能变化，涉及多个概念的综合应用和关联分析，需要理解材料成分、热处理工艺与显微组织之间的关系，并进行一定的推理和解释。 | 难度: 在选择题中属于较高难度，需要综合理解材料科学中的多个概念（如不同钢材的淬火特性、马氏体和残余奥氏体的形成条件及其对性能的影响），并进行多步分析和关联。题目要求考生不仅知道T12钢和45钢的区别，还要预测在错误工艺下得到的微观组织及其性能影响，这需要较深的知识掌握和综合分析能力。", "convertible": true, "correct_option": "The microstructure will consist of martensite, a significant amount of retained austenite, and a small amount of carbide. Properties: Martensite is hard and brittle, retained austenite has low hardness, resulting in non-uniform properties.", "choice_question": "If the bolts on the gear hobbing machine were mistakenly made of T12 steel instead of 45 steel and the quenching process for 45 steel was still applied, what microstructure and properties will be obtained?", "conversion_reason": "The answer is a standard description of microstructure and properties, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Martensite with retained austenite and carbides, leading to non-uniform hardness", "B": "Fully martensitic structure with uniform high hardness", "C": "Pearlite and ferrite mixture with moderate strength", "D": "Bainitic structure with good toughness but insufficient hardness" }, "correct_answer": "A", "explanation": "The correct answer is A because T12 steel is hypereutectoid with high carbon content, resulting in retained austenite and carbides after quenching. Option B is incorrect because the high carbon content prevents full martensitic transformation. Option C exploits the common misconception that wrong heat treatment always leads to softer structures. Option D uses the bainite confusion trap, as bainite requires specific cooling rates not achieved in standard quenching.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3153, "question": "In stable ZrO2 material, cations form an fcc structure, and anions occupy tetrahedral interstitial sites. If 20 mol% CaO is added, calculate how many anions are needed for 100 cations?", "answer": "Since the amount of CaO added to ZrO2 is 20 mol%, the total charge number for 100 cations is 20×2 + 80×4 = 360. To maintain electrical neutrality, the required number of O2− anions is 360 ÷ 2 = 180.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算需要的阴离子数量），并应用了电荷平衡的公式来解决问题。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及电荷平衡的概念应用和综合分析。虽然计算本身不复杂，但需要理解掺杂对晶体结构的影响以及电荷平衡的原理，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解电荷平衡的概念，进行多步计算（包括摩尔百分比换算、电荷数求和、电荷平衡计算），并综合应用材料化学和晶体结构知识。虽然题目提供了明确的解题路径，但涉及的步骤和概念关联使其高于基础选择题的难度水平。", "convertible": true, "correct_option": "180", "choice_question": "In stable ZrO2 material, cations form an fcc structure, and anions occupy tetrahedral interstitial sites. If 20 mol% CaO is added, how many anions are needed for 100 cations to maintain electrical neutrality?", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "180", "B": "200", "C": "160", "D": "190" }, "correct_answer": "A", "explanation": "The correct answer is 180 because in ZrO2 with 20 mol% CaO doping, each Ca2+ replaces one Zr4+ cation, creating oxygen vacancies for charge compensation. For 100 cations (80 Zr4+ and 20 Ca2+), the total positive charge is 80*4 + 20*2 = 360. Each O2- carries -2 charge, so 180 anions are needed for neutrality. Option B (200) is a trap for those assuming pure ZrO2 stoichiometry. Option C (160) results from incorrect vacancy calculation. Option D (190) is a midpoint distractor exploiting uncertainty in defect chemistry.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3442, "question": "If Cr12MoV steel is selected to manufacture cold work molds, what heat treatment process should be formulated? Why?", "answer": "For Cr12MoV steel used in cold work molds, the heat treatment process is the primary hardening method: quenching at 980～1030‰ and tempering at 200-270°C. Reason: The primary hardening method of Cr12MoV steel can provide the steel with high hardness and wear resistance, minimal heat treatment deformation, and most molds made of Cr12MoV steel without special requirements adopt this method.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释Cr12MoV钢制造冷作模具时应采用的热处理工艺及其原因，答案提供了详细的工艺参数和理论依据，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求制定Cr12MoV钢的热处理工艺并解释原因，涉及多步热处理过程（淬火和回火）的选择和参数设定，以及这些工艺对材料性能（硬度、耐磨性、变形）的影响。这需要综合理解材料的热处理原理和具体应用场景，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生不仅知道Cr12MoV钢的热处理工艺，还需要理解为什么选择这种工艺（高硬度、耐磨性、热处理变形小等）。这涉及到对材料性能和应用的综合理解，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Quenching at 980～1030°C and tempering at 200-270°C", "choice_question": "What is the recommended heat treatment process for Cr12MoV steel used in cold work molds?", "conversion_reason": "The answer is a standard and specific heat treatment process, which can be presented as a clear option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Quenching at 980～1030°C and tempering at 200-270°C", "B": "Quenching at 850～900°C and tempering at 400-450°C", "C": "Quenching at 1050～1100°C and tempering at 150-200°C", "D": "Quenching at 750～800°C and tempering at 500-550°C" }, "correct_answer": "A", "explanation": "The correct answer is A because Cr12MoV steel requires high quenching temperatures (980-1030°C) to dissolve sufficient carbides for hardness, followed by low tempering (200-270°C) to maintain high hardness while relieving stresses. Option B uses typical tempering temperatures for tool steels but is too low for quenching this alloy. Option C's higher quenching may cause excessive austenite retention. Option D's temperatures are more suitable for annealing than hardening. The interference strategies exploit: 1) Common tool steel treatment ranges (B), 2) The intuitive 'higher quenching=better' fallacy (C), and 3) Confusion with stress-relief treatments (D).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 290, "question": "Analyze the effect of strain energy on the shape of the new phase", "answer": "Strain energy can influence the shape of the new phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析应变能对新相形状的影响，需要文字解释和论述，答案形式为简短的文字说明而非计算或选择 | 知识层次: 题目要求分析应变能对新相形状的影响，这需要综合运用材料科学中的相变理论、弹性力学和热力学知识，进行推理分析和机理解释。涉及多个概念的关联和深层次理解，属于较高层次的认知要求。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求分析应变能对新相形状的影响，这涉及到对材料科学中相变机理的深入理解。正确选项虽然简洁，但背后需要考生掌握应变能与相变形状之间的复杂关系，并能进行机理层面的解释。这种题目不仅测试基础概念，还要求考生能够综合运用知识进行推理分析，因此在选择题型中属于机理深度解释的难度等级。", "convertible": true, "correct_option": "Strain energy can influence the shape of the new phase.", "choice_question": "Analyze the effect of strain energy on the shape of the new phase. Which of the following is correct?", "conversion_reason": "The answer is a standard statement that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct analysis.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Strain energy can influence the shape of the new phase", "B": "Strain energy only affects the nucleation rate, not the morphology", "C": "The shape is solely determined by interfacial energy minimization", "D": "Strain energy causes all new phases to form as perfect spheres" }, "correct_answer": "A", "explanation": "The correct answer is A because strain energy can indeed influence the shape of the new phase by favoring morphologies that minimize elastic strain energy. Option B is a cognitive bias trap, exploiting the common knowledge that strain energy affects nucleation while hiding its morphological effects. Option C is a professional intuition trap, presenting a partially true statement (interfacial energy is important) while ignoring strain energy's role. Option D is a multi-level verification trap, combining the correct concept (strain energy affects shape) with an extreme and incorrect generalization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 507, "question": "Dislocation slip", "answer": "Dislocation slip: Under a certain stress, the movement of dislocations where the dislocation line moves along the slip plane.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Dislocation slip\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征 | 知识层次: 题目考查对位错滑移这一基本概念的定义和简单描述，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆和识别\"dislocation slip\"的基本定义，属于基础概念记忆层次。题目描述直接给出了定义，没有涉及复杂的概念体系或需要推理分析的步骤，因此属于最简单的难度等级。", "convertible": true, "correct_option": "Under a certain stress, the movement of dislocations where the dislocation line moves along the slip plane.", "choice_question": "Which of the following best describes dislocation slip?", "conversion_reason": "The answer is a standard definition of a concept, which can be converted into a multiple-choice question format by presenting it as the correct option among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Under a certain stress, the movement of dislocations where the dislocation line moves along the slip plane", "B": "The spontaneous rearrangement of atomic planes to minimize system energy without external stress", "C": "The collective motion of vacancies leading to permanent deformation in crystalline materials", "D": "A stress-independent diffusion process that occurs at temperatures above the recrystallization point" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes dislocation slip as the stress-driven movement of dislocations along specific crystallographic planes. Option B is a cognitive bias trap, describing annealing rather than slip. Option C exploits vacancy diffusion misconceptions, a common confusion in deformation mechanisms. Option D is a multi-level trap combining stress-independence and recrystallization concepts that don't apply to slip.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3186, "question": "Directly observing the aluminum sample, the dislocation density within the grains is ρ=5×10^13/m^2. If the angle between subgrains is 5°, estimate the dislocation spacing at the interface (the lattice constant of aluminum a=2.8×10^-10m).", "answer": "Using the formula D≈b/θ, where b is the magnitude of the Burgers vector of the dislocation and D is the dislocation spacing, the Burgers vector b=[101], so b_Al=a/2×√2=2.8×10^-10×√2/2≈1.98×10^-10m. θ=5/57.3=0.087, substituting into the expression for D, we obtain D=2.28×10^-9m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及使用特定的公式（D≈b/θ）和给定的参数（如Burgers vector、角度等）来估算位错间距。答案提供了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算（Burgers向量计算、角度转换、间距公式应用），涉及位错理论中多个概念的关联（位错密度、亚晶界角度、位错间距），需要综合分析能力，但不需要复杂的机理解释或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解位错密度、亚晶界角度、位错间距等多个概念，并进行多步计算（包括Burgers矢量计算、角度转换和最终间距计算）。虽然题目提供了计算公式，但需要正确应用材料常数和单位转换，对概念理解和计算能力要求较高。", "convertible": true, "correct_option": "2.28×10^-9m", "choice_question": "Directly observing the aluminum sample, the dislocation density within the grains is ρ=5×10^13/m^2. If the angle between subgrains is 5°, estimate the dislocation spacing at the interface (the lattice constant of aluminum a=2.8×10^-10m). The dislocation spacing D is approximately:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.28×10^-9m", "B": "3.14×10^-9m", "C": "1.12×10^-9m", "D": "4.56×10^-9m" }, "correct_answer": "A", "explanation": "The correct answer is calculated using D = a/θ (in radians), where θ=5°=0.0873 radians. Thus D=2.8×10^-10/0.0873≈2.28×10^-9m. Option B uses π×10^-9 to exploit rounding errors. Option C incorrectly uses half the correct value by misapplying the angle bisector concept. Option D doubles the correct value by confusing grain boundary spacing with individual dislocation spacing.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1483, "question": "Explain the role of Cottrell atmosphere in strengthening metals", "answer": "Cottrell atmosphere: In BCC crystals (such as carbon steel), small-sized atoms like C and N preferentially distribute in the tensile stress region of edge dislocations, pinning the dislocations. To move the dislocations, they must be torn away from the pinning effect, requiring additional stress, thereby increasing the material's strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Cottrell atmosphere在金属强化中的作用，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释Cottrell atmosphere在金属强化中的作用机制，涉及位错理论、原子扩散和应力场相互作用等复杂概念的综合运用和推理分析。需要深入理解位错与溶质原子的交互作用，以及这种交互如何导致材料强化的机理。 | 难度: 在选择题型中，该题目要求考生深入理解Cottrell atmosphere的机理及其对金属强化的影响，涉及BCC晶体结构、位错理论、溶质原子与位错的相互作用等复杂概念的综合运用。考生需要能够解释溶质原子在位错应力场中的分布及其对位错运动的阻碍作用，并理解这一现象如何导致材料强度的提高。这种深度机理解释和复杂现象全面分析的要求，使得该题目在选择题型中属于最高难度等级。", "convertible": true, "correct_option": "Cottrell atmosphere: In BCC crystals (such as carbon steel), small-sized atoms like C and N preferentially distribute in the tensile stress region of edge dislocations, pinning the dislocations. To move the dislocations, they must be torn away from the pinning effect, requiring additional stress, thereby increasing the material's strength.", "choice_question": "Which of the following best describes the role of Cottrell atmosphere in strengthening metals?", "conversion_reason": "The answer is a standard explanation of a concept, which can be presented as the correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cottrell atmosphere: In BCC crystals (such as carbon steel), small-sized atoms like C and N preferentially distribute in the tensile stress region of edge dislocations, pinning the dislocations. To move the dislocations, they must be torn away from the pinning effect, requiring additional stress, thereby increasing the material's strength.", "B": "Cottrell atmosphere refers to the formation of solute-rich zones around screw dislocations in FCC metals, which increases the critical resolved shear stress required for plastic deformation.", "C": "Cottrell atmosphere describes the clustering of vacancies around edge dislocations in HCP metals, creating a local stress field that impedes dislocation motion and enhances yield strength.", "D": "Cottrell atmosphere involves the segregation of large substitutional atoms to compressive stress regions of mixed dislocations in BCC metals, effectively increasing the Peierls-Nabarro stress." }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the Cottrell atmosphere mechanism in BCC metals where interstitial atoms pin edge dislocations. Option B is incorrect because it mistakenly associates the phenomenon with screw dislocations in FCC metals. Option C is wrong as it confuses the concept with vacancy clustering in HCP structures. Option D contains partial truths but incorrectly describes the mechanism with substitutional atoms and mixed dislocations, creating a subtle but critical misconception.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1550, "question": "2. Intermediate phase", "answer": "A compound formed by two pure components with a structure different from theirs, whose composition lies between the two pure components.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Intermediate phase\"进行文字解释和论述，答案是一个详细的定义描述，而不是选择、判断或计算。 | 知识层次: 题目考查对中间相（Intermediate phase）这一基本概念的定义和特征的理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但要求考生不仅记住中间相的定义，还需要理解其结构特点和成分范围。这比单纯记忆基本定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "A compound formed by two pure components with a structure different from theirs, whose composition lies between the two pure components.", "choice_question": "Which of the following best describes an intermediate phase?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question by asking for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A compound formed by two pure components with a structure different from theirs, whose composition lies between the two pure components", "B": "A metastable phase that forms during rapid cooling and transforms to equilibrium phases upon annealing", "C": "A solid solution phase with properties intermediate between the two pure components", "D": "A transition region between two phases in a phase diagram where properties gradually change" }, "correct_answer": "A", "explanation": "The correct answer is A because an intermediate phase is specifically a distinct compound with its own crystal structure, not a solid solution or transition region. Option B describes a metastable phase, not an intermediate phase. Option C is incorrect because it describes a solid solution rather than a distinct compound. Option D is a common misconception describing a phase boundary region rather than a true intermediate phase.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1447, "question": "For an edge dislocation line, what is the relationship between the direction of its slip motion and the Burgers vector?", "answer": "Parallel", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释边缘位错线的滑移方向与Burgers矢量之间的关系，需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目考查对位错滑移方向与伯格斯矢量关系这一基本概念的记忆和理解，属于材料科学中位错理论的基础知识点。 | 难度: 该题目属于基础概念记忆类型，仅需掌握边缘位错线的滑移方向与其伯格斯矢量之间的关系这一基本定义。在选择题型中，只需识别正确选项\"Parallel\"，无需进行复杂的概念解释或分析，因此属于最低难度等级。", "convertible": true, "correct_option": "Parallel", "choice_question": "For an edge dislocation line, what is the relationship between the direction of its slip motion and the Burgers vector?", "conversion_reason": "The answer is a standard term (Parallel), which can be presented as a single correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Parallel", "B": "Perpendicular", "C": "At 45° angle", "D": "Depends on the crystal structure" }, "correct_answer": "A", "explanation": "The correct answer is A because for an edge dislocation, the slip motion occurs in the direction parallel to the Burgers vector. Option B is a cognitive bias trap, as it mimics the relationship between dislocation line and Burgers vector. Option C exploits the common 45° slip systems in FCC crystals. Option D is a multi-level verification trap, suggesting a plausible but incorrect dependence on crystal structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4296, "question": "Suppose that a wing component on an aircraft is fabricated from an aluminum alloy that has a plane strain fracture toughness of 40 MPa \\sqrt{m} (36.4 k \\left.\\mathrm{si} \\sqrt{m}\\right). It has been determined that fracture results at a stress of 365 MPa(53,000 psi) when the maximum internal crack length is 2.5 mm(0.10 in.). For this same component and alloy, compute the stress level at which fracture will occur for a critical internal crack length of 4.0 mm(0.16 in.).", "answer": "the stress level at which fracture will occur for a critical internal crack length of 4.0mm is 288 MPa (41,500 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解应力水平，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及平面应变断裂韧性和应力强度因子的概念关联，需要综合分析裂纹长度和应力水平的关系。虽然计算过程较为直接，但需要理解并应用相关公式，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解断裂力学中的平面应变断裂韧性概念，并应用应力强度因子公式进行多步计算。题目要求考生能够将给定的断裂参数（K_IC、应力、裂纹长度）关联起来，并通过公式推导出新的应力水平。虽然选项已经给出正确答案，但考生仍需具备综合分析能力才能验证选项的正确性，这比单纯记忆或简单计算更复杂。", "convertible": true, "correct_option": "288 MPa (41,500 psi)", "choice_question": "For the same wing component and alloy, compute the stress level at which fracture will occur for a critical internal crack length of 4.0 mm (0.16 in.).", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "288 MPa (41,500 psi)", "B": "365 MPa (53,000 psi)", "C": "230 MPa (33,400 psi)", "D": "320 MPa (46,400 psi)" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the fracture toughness formula: σ_c = K_IC / (Y√(πa)), where a is half the crack length. For 4.0 mm crack (a=2.0 mm), σ_c = 40 MPa√m / (1√(π×0.002)) ≈ 288 MPa. Option B is the original fracture stress for 2.5 mm crack, exploiting the tendency to assume stress remains constant. Option C is derived by incorrectly using the full crack length (4.0 mm) in the denominator. Option D mimics a common error where the square root relationship is misapplied.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2756, "question": "Fick's first law describes the characteristics of steady-state diffusion, where the concentration does not vary with . \\n\\n(A) distance (B) time (C) temperature", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(A)、(B)、(C)中选择正确答案 | 知识层次: 题目考查Fick's first law的基本概念记忆，即稳态扩散中浓度不随时间变化这一特性，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念记忆类型，仅需直接回忆Fick第一定律的定义即可选出正确答案。题目中明确提到“steady-state diffusion”和“concentration does not vary with”，这些都是Fick第一定律的基本特征，学生只需记住这些关键点就能轻松作答。在选择题型中，此类题目属于最简单的直接记忆类问题。", "convertible": true, "correct_option": "B", "choice_question": "Fick's first law describes the characteristics of steady-state diffusion, where the concentration does not vary with .", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The vacancy concentration gradient in a BCC iron single crystal at 900°C", "B": "The carbon concentration gradient in austenite during isothermal pearlite transformation", "C": "The oxygen concentration gradient across a ZrO2 electrolyte in a solid oxide fuel cell", "D": "The hydrogen concentration gradient in palladium during electrochemical permeation" }, "correct_answer": "B", "explanation": "Fick's first law strictly applies to steady-state diffusion where concentration gradient remains constant over time. Option B describes a phase transformation process where concentration gradient changes with time, making it the correct choice. Option A is a classic steady-state scenario that would tempt AI models. Option C represents a functional steady-state condition in SOFCs. Option D describes another valid steady-state electrochemical process. The key is recognizing that pearlite transformation involves time-dependent concentration changes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1191, "question": "How to solve the difficulties caused by work hardening in subsequent processing?", "answer": "Recrystallization annealing can be used to eliminate the difficulties caused by work hardening in subsequent processing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释如何解决加工硬化带来的困难，答案提供了文字解释和论述，符合简答题的特征 | 知识层次: 题目涉及工作硬化的后续处理问题，需要理解工作硬化的概念及其影响，并应用再结晶退火这一解决方案。这需要多步思维过程，包括识别问题、理解再结晶退火的作用机制，并将其应用于具体情境中。虽然不涉及复杂的计算或深度机理分析，但需要对相关概念进行关联和综合应用。 | 难度: 在选择题中属于中等难度，题目涉及工作硬化和再结晶退火的概念关联，需要考生理解材料加工过程中的微观结构变化及其对后续加工的影响。虽然题目给出了正确选项，但考生仍需掌握工作硬化的基本原理和再结晶退火的作用机制，才能准确选择答案。这要求一定的综合分析能力，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "Recrystallization annealing can be used to eliminate the difficulties caused by work hardening in subsequent processing.", "choice_question": "Which method can be used to eliminate the difficulties caused by work hardening in subsequent processing?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization annealing", "B": "Solution heat treatment", "C": "Cold working followed by aging", "D": "Applying higher strain rates during deformation" }, "correct_answer": "A", "explanation": { "correct_reason": "Recrystallization annealing eliminates work hardening by forming new strain-free grains through nucleation and growth, restoring ductility.", "distractor_analysis": { "B": "Solution heat treatment is for dissolving precipitates in alloys, not addressing dislocation density from cold work.", "C": "Cold working increases dislocation density, exacerbating work hardening; aging strengthens but doesn't restore ductility.", "D": "Higher strain rates would intensify work hardening by increasing dislocation multiplication." }, "cognitive_traps": { "B_trap": "Exploits confusion between annealing (correct) and solution treatment (common in alloy processing).", "C_trap": "Mimics common age-hardening sequences but reverses the required softening step.", "D_trap": "Appeals to intuitive 'counterforce' thinking but physically worsens the problem." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3298, "question": "Compare the formation temperatures of bainitic transformation, pearlitic transformation, and martensitic transformation", "answer": "Pearlitic transformation occurs in the high-temperature region (below A), bainitic transformation occurs in the medium-temperature region (below B), and martensitic transformation occurs in the low-temperature region (below Ms).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较三种相变的形成温度，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查对三种相变温度范围的基础概念记忆和理解，无需复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个相变温度区域的比较，但正确选项已经明确给出了各个相变发生的温度区域（高温、中温、低温）及其对应的相变类型（珠光体、贝氏体、马氏体）。这属于基础概念记忆的范畴，只需要考生能够区分和记忆不同相变的温度范围即可，不需要进行复杂的分析或推导。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "Pearlitic transformation occurs in the high-temperature region (below A), bainitic transformation occurs in the medium-temperature region (below B), and martensitic transformation occurs in the low-temperature region (below Ms).", "choice_question": "Which of the following correctly describes the formation temperatures of bainitic transformation, pearlitic transformation, and martensitic transformation?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question because the answer is a standard description of the formation temperatures of the transformations. The question can be rephrased to ask for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pearlitic transformation occurs in the high-temperature region (below A1), bainitic transformation occurs in the medium-temperature region (below Bs), and martensitic transformation occurs in the low-temperature region (below Ms)", "B": "All three transformations occur below the eutectoid temperature, with pearlite forming first, followed by bainite, and martensite forming last", "C": "Martensitic transformation occurs at the highest temperature (above A3), followed by bainitic transformation, with pearlitic transformation occurring at the lowest temperature", "D": "Bainitic and pearlitic transformations occur simultaneously in the same temperature range, while martensitic transformation occurs at much lower temperatures" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the temperature ranges for these phase transformations in steel. Pearlite forms at higher temperatures just below the eutectoid temperature (A1), bainite at intermediate temperatures below Bs, and martensite at low temperatures below Ms. Option B is incorrect because it suggests all transformations occur below the eutectoid temperature with sequential timing, ignoring the distinct temperature ranges. Option C reverses the actual temperature sequence, creating a fundamental misconception. Option D incorrectly groups bainite and pearlite formation together, which is a common oversimplification trap. These distractors exploit common cognitive biases in phase transformation understanding, including sequence confusion, temperature range misattribution, and transformation mechanism oversimplification.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3319, "question": "Indicate the main purpose of normalizing 20 steel gears and the microstructure after normalizing", "answer": "Normalizing of 20 steel: improve machinability.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释正常化处理20钢齿轮的主要目的以及处理后的显微组织，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对正火处理目的和结果的基础概念记忆，属于基本原理的记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆20钢正火的主要目的和微观结构，属于基础概念记忆性知识。题目直接给出了正确选项，无需复杂分析或推理，仅需识别和回忆相关定义即可。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "improve machinability", "choice_question": "What is the main purpose of normalizing 20 steel gears?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "improve machinability", "B": "increase surface hardness", "C": "enhance corrosion resistance", "D": "reduce residual stresses" }, "correct_answer": "A", "explanation": "The correct answer is A because normalizing primarily refines the grain structure to improve machinability. Option B is a cognitive bias trap - while hardness may slightly increase, this is not the main purpose. Option C exploits material science intuition by suggesting a property often associated with heat treatment, but normalizing does not significantly affect corrosion resistance. Option D is a multi-level verification trap - while stress relief occurs, it's a secondary effect compared to the primary goal of machinability improvement.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2359, "question": "What is the relationship between functionality and the structural morphology of polymers?", "answer": "If the functionality of a polymer monomer equals 2, the monomer can only form long molecular chains without branches, resulting in a linear structure. If the functionality equals 3 or is greater than 3, during polymerization, one functionality of a trifunctional monomer provides covalent cross-linking with another molecular chain, forming a network, which is a three-dimensional structure. Such a polymer is essentially a single molecule with an extremely large molecular weight.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释聚合物功能性与结构形态之间的关系，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释聚合物功能性与结构形态之间的关系，涉及对功能性的理解、聚合反应机制的分析以及不同功能性导致的结构差异的综合论述。这需要将多个概念关联起来并进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，题目要求考生不仅理解聚合物功能性与结构形态的基本概念，还需要综合分析不同功能度（2 vs ≥3）对聚合物分子链形成的具体影响。正确选项涉及多步逻辑推理（从功能度推导链结构类型）和跨概念关联（共价交联与三维网络形成机制），这超出了单纯记忆或简单应用的范畴。此外，题目隐含了对\"功能度决定聚合物拓扑结构\"这一核心原理的深度理解，需在选项层面辨析线性结构与网络结构的形成条件，符合选择题型中\"多角度分析论述\"的等级4标准。", "convertible": true, "correct_option": "If the functionality of a polymer monomer equals 2, the monomer can only form long molecular chains without branches, resulting in a linear structure. If the functionality equals 3 or is greater than 3, during polymerization, one functionality of a trifunctional monomer provides covalent cross-linking with another molecular chain, forming a network, which is a three-dimensional structure. Such a polymer is essentially a single molecule with an extremely large molecular weight.", "choice_question": "What is the relationship between functionality and the structural morphology of polymers?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Functionality determines the degree of branching but has no effect on crystallinity", "B": "Higher functionality monomers always lead to higher tensile strength regardless of polymerization conditions", "C": "Bifunctional monomers can form crosslinked networks when heated above their glass transition temperature", "D": "Tetrafunctional monomers produce linear polymers with alternating rigid and flexible segments" }, "correct_answer": "A", "explanation": "Correct answer A is accurate because functionality primarily affects branching (linear vs network structures) but crystallinity depends on chain regularity and packing. Option B is a cognitive bias trap - while crosslinking can increase strength, uncontrolled high functionality may create brittle networks. Option C exploits a common misconception about Tg's role in crosslinking. Option D reverses the expected behavior of tetrafunctional monomers to create a counterintuitive but false scenario.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 570, "question": "Given the diffusion constant of carbon in γ-Fe D0=2.0×10^-5m^2/s and the activation energy for diffusion Q=140×10^3J/mol, how long is required to achieve the same carburizing thickness at 870°C as that obtained by carburizing for 10 hours at 927°C? (Ignore the difference in solubility of carbon in γ-Fe at different temperatures)", "answer": "20.12 hours are required.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（扩散方程）来求解达到相同渗碳厚度所需的时间，答案是一个具体的数值结果（20.12 hours）。 | 知识层次: 题目需要进行多步计算，包括应用扩散公式（Arrhenius方程）计算不同温度下的扩散系数，然后根据扩散厚度与时间的平方根关系进行时间换算。这需要理解扩散机制和温度对扩散系数的影响，并进行综合分析。 | 难度: 在选择题中属于中等难度，需要理解扩散常数、活化能、温度对扩散速率的影响等多个概念，并进行多步计算和综合分析。虽然题目提供了必要的参数，但解题过程涉及Arrhenius方程的应用、温度转换、时间计算等多个步骤，要求考生具备较强的综合计算能力和概念关联能力。", "convertible": true, "correct_option": "20.12 hours", "choice_question": "Given the diffusion constant of carbon in γ-Fe D0=2.0×10^-5m^2/s and the activation energy for diffusion Q=140×10^3J/mol, how long is required to achieve the same carburizing thickness at 870°C as that obtained by carburizing for 10 hours at 927°C? (Ignore the difference in solubility of carbon in γ-Fe at different temperatures)", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct option among plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "20.12 hours", "B": "15.75 hours", "C": "25.30 hours", "D": "10.06 hours" }, "correct_answer": "A", "explanation": "The correct answer is A (20.12 hours) because it requires precise application of the Arrhenius equation to calculate the diffusion coefficient at both temperatures, then using the relationship that carburizing thickness is proportional to the square root of (D*t). The incorrect options exploit common calculation errors: B (15.75 hours) results from miscalculating the temperature conversion to Kelvin, C (25.30 hours) comes from incorrectly inverting the temperature ratio, and D (10.06 hours) is a half-value trap that might seem plausible if one forgets the square root relationship with time.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3342, "question": "If a $\\phi5\\$ hot-rolled steel specimen is heated to 650℃, held isothermally for 15s, and then quenched in water, can the isothermal transformation curve be used to analyze the final microstructure obtained?", "answer": "No. The isothermal transformation curve describes the transformation of undercooled austenite. The hot-rolled eutectoid steel heated to 650℃ does not undergo austenitization.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断一个陈述的对错（是否可以使用等温转变曲线分析最终获得的微观结构），答案直接给出了\"是/否\"的判断（No），并提供了简要解释。这符合判断题的特征。 | 知识层次: 题目考查对等温转变曲线基本概念的理解，即它仅适用于过冷奥氏体的转变，而不适用于未发生奥氏体化的情况。这属于基础概念的记忆和理解。 | 难度: 在选择题中属于中等难度，需要理解等温转变曲线的基本概念及其应用条件，并判断题目描述的情况是否符合这些条件。虽然不涉及复杂的分析步骤，但需要对基础概念有一定的理解和应用能力。", "convertible": true, "correct_option": "No. The isothermal transformation curve describes the transformation of undercooled austenite. The hot-rolled eutectoid steel heated to 650℃ does not undergo austenitization.", "choice_question": "If a $\\phi5\\$ hot-rolled steel specimen is heated to 650℃, held isothermally for 15s, and then quenched in water, can the isothermal transformation curve be used to analyze the final microstructure obtained?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "For all types of steel, the isothermal transformation curve can accurately predict the final microstructure when the specimen is heated to any temperature below the eutectoid temperature, held isothermally, and then quenched.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "The isothermal transformation curve is specifically applicable to undercooled austenite. If the steel is not fully austenitized (e.g., when heated below the eutectoid temperature), the curve cannot be used to analyze the final microstructure. This statement incorrectly generalizes the applicability of the curve to all temperatures and all steel types, ignoring the fundamental requirement of austenitization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 5, "correct_answers": 5, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1653, "question": "Crystal family", "answer": "Based on the number of higher-order axes $(n>2)$ in the crystal structure, crystals are divided into lower (no higher-order axis), intermediate (one higher-order axis), and higher (more than one higher-order axis) crystal families.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对晶体家族进行分类并解释分类依据，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查晶体家族的基本分类标准，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及晶体分类的基础概念记忆，但需要理解\"higher-order axes\"的定义以及如何根据其数量进行分类。这比单纯记忆基本定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。题目要求考生能够解释和描述晶体分类的标准，属于概念解释和描述的难度层次。", "convertible": true, "correct_option": "Based on the number of higher-order axes $(n>2)$ in the crystal structure, crystals are divided into lower (no higher-order axis), intermediate (one higher-order axis), and higher (more than one higher-order axis) crystal families.", "choice_question": "Crystal families are classified based on:", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The relative lengths of the crystallographic axes and the angles between them", "B": "The number of higher-order axes (n>2) in the crystal structure", "C": "The type of Bravais lattice the crystal belongs to", "D": "The presence or absence of a center of symmetry in the unit cell" }, "correct_answer": "B", "explanation": "The correct answer is B because crystal families are specifically classified based on the number of higher-order symmetry axes (n>2). This classification divides crystals into lower (no higher-order axis), intermediate (one higher-order axis), and higher (more than one higher-order axis) families. Option A is a cognitive bias trap describing crystal systems (not families) classification. Option C exploits professional intuition by referencing Bravais lattices which are related but distinct from family classification. Option D is a multi-level verification trap using symmetry elements that are important for point groups but not for family classification.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3236, "question": "At room temperature, the plastic deformation modes of metal polycrystals are A. Slip, twinning, creep B. Slip, twinning, kinking C. Slip, climb, cross-slip D. Slip, twinning, grain boundary sliding", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项（A、B、C、D）中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查金属多晶体在室温下的塑性变形模式的基本概念记忆，属于基础概念记忆性知识。 | 难度: 在选择题中属于中等偏下难度，需要理解金属多晶体在室温下的塑性变形模式，并对选项中的概念进行简单辨析。虽然涉及多个变形模式（滑移、孪生、扭折），但这些都是基础概念，不需要复杂的分析或深度理解即可选出正确答案。", "convertible": true, "correct_option": "B. Slip, twinning, kinking", "choice_question": "At room temperature, the plastic deformation modes of metal polycrystals are", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip, twinning, creep", "B": "Slip, twinning, kinking", "C": "Slip, climb, cross-slip", "D": "Slip, twinning, grain boundary sliding" }, "correct_answer": "B", "explanation": "The correct answer is B because at room temperature, the primary plastic deformation modes in metal polycrystals are slip (dislocation glide), twinning, and kinking. Option A is incorrect because creep is a high-temperature phenomenon. Option C is incorrect because climb and cross-slip are dislocation mechanisms that require thermal activation, making them less dominant at room temperature. Option D is incorrect because grain boundary sliding is also a high-temperature deformation mechanism. The difficulty lies in distinguishing between room-temperature and high-temperature mechanisms, which can confuse AI models relying on general material science knowledge without considering the temperature constraint.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2080, "question": "Point out the errors in the following concepts and correct them: (23) During metal crystallization, the dynamic undercooling required for crystal growth is sometimes greater than the critical undercooling required for nucleation.", "answer": "The dynamic undercooling is smaller than the critical undercooling required for nucleation.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求指出并纠正错误概念，答案直接给出了正确的陈述，类似于判断陈述的对错并给出正确版本 | 知识层次: 题目考查金属结晶过程中动态过冷度和临界过冷度的基本概念记忆和理解，属于基础概念层面的知识。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度等级。题目要求考生理解金属结晶过程中动态过冷和临界过冷的相对大小关系，并判断原陈述的错误之处。这需要考生掌握基础概念并能进行简单的比较分析，但不需要复杂的推理或多概念整合，因此属于中等难度。", "convertible": true, "correct_option": "The dynamic undercooling is smaller than the critical undercooling required for nucleation.", "choice_question": "Point out the errors in the following concepts and correct them: (23) During metal crystallization, the dynamic undercooling required for crystal growth is sometimes greater than the critical undercooling required for nucleation.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all metal crystallization processes, the critical undercooling for nucleation is always greater than the dynamic undercooling required for crystal growth.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While generally true that nucleation requires greater undercooling than growth, this is not absolute for all cases. Some special conditions (e.g., extremely high purity metals or specific alloy systems) may exhibit exceptions where dynamic undercooling approaches or exceeds critical undercooling. The use of 'always' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 579, "question": "What phenomenon is caused by the interaction between dislocations and solute atoms in alloys?", "answer": "The interaction between dislocations and solute atoms in alloys forms atmospheres, leading to yield phenomena and strain aging.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释一个现象（dislocations和solute atoms的相互作用导致的phenomenon），答案需要文字解释和论述（forms atmospheres, leading to yield phenomena and strain aging），属于简答题类型。 | 知识层次: 题目要求解释位错与溶质原子相互作用导致的物理现象（屈服现象和应变时效），这需要深入理解位错理论、溶质原子与位错的相互作用机制，以及这些相互作用对材料力学性能的影响。这种解释需要综合运用多个概念，并进行机理层面的分析，属于较高层次的认知要求。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解位错与溶质原子的基本相互作用，还需要掌握由此产生的复杂现象（如柯氏气团形成、屈服现象和应变时效）的全面机理。这需要考生具备将多个高阶概念整合分析的能力，并能解释这些现象之间的因果关系。在选择题的有限选项中，正确选项涉及了材料科学中较为深入的理论知识，远超出基础概念识记层面，属于需要复杂分析和综合判断的题目类型。", "convertible": true, "correct_option": "The interaction between dislocations and solute atoms in alloys forms atmospheres, leading to yield phenomena and strain aging.", "choice_question": "What phenomenon is caused by the interaction between dislocations and solute atoms in alloys?", "conversion_reason": "The answer is a standard and concise description of a phenomenon, making it suitable for conversion into a multiple-choice question format where this description can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Formation of Cottrell atmospheres leading to yield point phenomena", "B": "Precipitation hardening through Guinier-Preston zones", "C": "Dislocation climb due to vacancy diffusion", "D": "Recrystallization through grain boundary migration" }, "correct_answer": "A", "explanation": "The correct answer is A because solute atoms interact with dislocations to form Cottrell atmospheres, which pin dislocations and cause yield point phenomena. Option B describes a different strengthening mechanism not directly caused by dislocation-solute interaction. Option C involves dislocation motion mechanisms unrelated to solute atoms. Option D describes a high-temperature process independent of dislocation-solute interactions. The distractors exploit common confusions between different strengthening mechanisms in metallurgy.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1999, "question": "When a dislocation is subjected to force, its motion direction is everywhere perpendicular to the dislocation line and can vary during movement. What should be the direction of the relative sliding of the crystal?", "answer": "It is always the direction of the Burgers vector.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释晶体相对滑动的方向，答案提供了文字解释和论述，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目需要理解位错运动的基本原理，并能够将位错线的运动方向与晶体的相对滑动方向联系起来。这涉及到对位错和Burgers向量的概念的综合应用，而不仅仅是简单的记忆或直接套用。虽然不需要复杂的推理或创新应用，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解位错运动的基本概念、Burgers矢量的定义以及它们之间的关系。题目要求考生能够将位错线的运动方向与晶体的相对滑动方向联系起来，并进行综合分析。虽然不涉及复杂的计算，但需要对相关概念有较深的理解和关联能力。", "convertible": true, "correct_option": "It is always the direction of the Burgers vector.", "choice_question": "When a dislocation is subjected to force, its motion direction is everywhere perpendicular to the dislocation line and can vary during movement. What should be the direction of the relative sliding of the crystal?", "conversion_reason": "The answer is a standard concept (Burgers vector direction), which can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The direction of the Burgers vector", "B": "The direction of the applied force", "C": "The direction perpendicular to both the dislocation line and Burgers vector", "D": "The direction parallel to the dislocation line" }, "correct_answer": "A", "explanation": "The correct answer is A because the relative sliding of the crystal must always align with the Burgers vector, which defines the magnitude and direction of lattice distortion caused by the dislocation. Option B is a cognitive bias trap, as the applied force direction is often mistakenly associated with slip direction. Option C exploits a common misconception about cross products in dislocation theory. Option D targets the intuitive but incorrect assumption that motion should parallel the dislocation line.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4363, "question": "Briefly cite the differences between pearlite, bainite, and spheroidite relative to mechanical properties.", "answer": "Bainite is harder and stronger than pearlite, which, in turn, is harder and stronger than spheroidite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求简要解释珠光体、贝氏体和球化体在机械性能上的差异，答案以文字解释的形式给出，符合简答题的特征。 | 知识层次: 题目要求比较三种不同显微组织（pearlite, bainite, spheroidite）的机械性能差异，需要理解这些组织的形成机制及其对性能的影响，并进行综合分析。这涉及多个概念的关联和比较，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念（珠光体、贝氏体、球化体）并进行比较分析，同时掌握它们之间的机械性能差异。虽然题目涉及多个概念，但在选择题型中通过选项可以辅助判断，降低了部分难度。", "convertible": true, "correct_option": "Bainite is harder and stronger than pearlite, which, in turn, is harder and stronger than spheroidite.", "choice_question": "Which of the following correctly describes the differences between pearlite, bainite, and spheroidite relative to mechanical properties?", "conversion_reason": "The answer is a standard comparison that can be presented as a correct option among other plausible but incorrect comparisons.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Bainite is harder and stronger than pearlite, which, in turn, is harder and stronger than spheroidite", "B": "Pearlite has higher ductility than bainite but lower hardness than spheroidite due to its lamellar structure", "C": "Spheroidite exhibits superior toughness compared to bainite because its spherical carbides minimize stress concentration", "D": "Bainite and pearlite have similar yield strengths but bainite shows better creep resistance at high temperatures" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the hardness hierarchy between these microstructures. Option B reverses the hardness relationship between pearlite and spheroidite. Option C is partially correct about spheroidite's toughness but incorrectly implies it's tougher than bainite. Option D creates a false equivalence in yield strength between bainite and pearlite while introducing an irrelevant creep resistance comparison.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3366, "question": "Why can shot peening and surface rolling significantly improve the fatigue limit of materials?", "answer": "Shot peening and surface rolling can create a very thin work-hardened layer on the surface of the workpiece, which not only has a higher yield limit but also contains significant compressive stress (400-500 MPa). This weakens the effect of tensile stress on the surface and delays the formation of surface cracks, thereby significantly improving the fatigue limit of the material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么喷丸和表面滚压能显著提高材料的疲劳极限，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要解释shot peening和surface rolling如何通过产生work-hardened层和压缩应力来改善材料的疲劳极限，这涉及到多个概念的关联和机理解释，需要综合运用材料科学的知识进行推理分析。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解表面处理工艺（喷丸和表面滚压）的基本作用，还需要深入掌握这些工艺如何通过形成加工硬化层和引入残余压应力来影响材料的疲劳极限。此外，题目还要求考生能够将这些机理与疲劳性能的改善联系起来，进行综合分析和推理。这种题目需要考生具备较高的知识整合能力和机理解释能力，属于复杂现象全面分析的层次。", "convertible": true, "correct_option": "Shot peening and surface rolling can create a very thin work-hardened layer on the surface of the workpiece, which not only has a higher yield limit but also contains significant compressive stress (400-500 MPa). This weakens the effect of tensile stress on the surface and delays the formation of surface cracks, thereby significantly improving the fatigue limit of the material.", "choice_question": "Why can shot peening and surface rolling significantly improve the fatigue limit of materials?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The processes create a work-hardened surface layer with compressive stresses that counteract tensile stresses and delay crack initiation", "B": "The surface treatments increase the elastic modulus of the material, making it more resistant to cyclic deformation", "C": "The mechanical impacts refine the grain structure throughout the entire material volume, improving overall strength", "D": "The treatments create a smoother surface finish that reduces stress concentration factors" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual mechanism: work-hardened layer with compressive stresses. B is wrong because elastic modulus is an intrinsic property not significantly changed by surface treatments. C is a half-truth as grain refinement is localized to the surface, not the entire volume. D is plausible but secondary, as surface finish improvement is not the primary fatigue limit enhancement mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3889, "question": "The nucleus of an atom contains neutrons?", "answer": "Yes, the nucleus of an atom contains neutrons.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（Yes/No），符合判断题的特征 | 知识层次: 题目考查原子核基本组成的记忆性知识，属于基础概念层次 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆原子核的基本组成即可作答，无需深入理解或分析多个概念。", "convertible": true, "correct_option": "Yes, the nucleus of an atom contains neutrons.", "choice_question": "The nucleus of an atom contains neutrons?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials are electrical insulators at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are insulators, some ceramic materials like certain perovskite oxides exhibit superconductivity or semiconducting properties at room temperature. This question tests understanding of material property exceptions and challenges the common generalization about ceramics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4101, "question": "[c] Structural composites are, in general, highly regarded for their specific strengths.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（T/F），符合判断题的特征 | 知识层次: 题目考查对结构复合材料基本特性的记忆和理解，属于基础概念层次。 | 难度: 该题目属于基础概念正误判断题，仅需记忆结构复合材料的基本特性（高比强度）即可作答，无需深入理解或分析多个概念，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "T", "choice_question": "[c] Structural composites are, in general, highly regarded for their specific strengths.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All polymer matrix composites exhibit superior fatigue resistance compared to monolithic metals under cyclic loading conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many polymer matrix composites do show excellent fatigue resistance, the absolute term 'all' makes this statement false. Some PMCs with certain fiber-matrix combinations or poor interfacial bonding may perform worse than some high-performance metals in fatigue. The statement also ignores loading direction considerations (e.g., transverse vs. longitudinal loading in composites).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2295, "question": "In a glass fiber reinforced nylon composite, the volume fraction of E-glass fiber is 0.3. The elastic moduli of E-glass and nylon are 72.4 GPa and 2.76 GPa, respectively. Calculate the fraction of the load borne by the fibers in the composite.", "answer": "If the interface bonding is good, the strain of the composite under force should be equal to that of the matrix and the fibers, i.e., $$ \\\\varepsilon_{\\\\mathrm{c}}={\\\\frac{\\\\sigma_{\\\\mathrm{c}}}{E_{\\\\mathrm{c}}}}=\\\\varepsilon_{\\\\mathrm{m}}={\\\\frac{\\\\sigma_{\\\\mathrm{m}}}{E_{\\\\mathrm{m}}}}=\\\\varepsilon_{\\\\mathrm{f}}={\\\\frac{\\\\sigma_{\\\\mathrm{f}}}{E_{\\\\mathrm{f}}}} $$ Thus, $$ \\\\frac{\\\\sigma_{\\\\mathrm{f}}}{\\\\sigma_{\\\\mathrm{m}}}=\\\\frac{E_{\\\\mathrm{f}}}{E_{\\\\mathrm{m}}}=\\\\varepsilon_{\\\\mathrm{f}}=\\\\frac{72.4~\\\\mathrm{GPa}}{2.76~\\\\mathrm{GPa}}=26.25 $$ The fraction of the load borne by the fibers is $$ \\\\varphi=\\\\frac{\\\\sigma_{\\\\mathrm{f}}}{\\\\sigma_{\\\\mathrm{f}}+\\\\sigma_{\\\\mathrm{m}}}=\\\\frac{1}{1+\\\\frac{\\\\sigma_{\\\\mathrm{m}}}{\\\\sigma_{\\\\mathrm{f}}}}=\\\\frac{1}{1+\\\\frac{1}{26.25}}=0.96 $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及弹性模量和载荷分配的计算，答案也展示了具体的计算过程和结果。 | 知识层次: 题目需要进行多步计算，涉及复合材料中纤维和基体的弹性模量比较，以及载荷分配的计算。虽然公式相对直接，但需要理解应变相等的条件，并进行适当的代数变换来求解载荷分数。这超出了简单应用的范围，但尚未达到复杂分析或高级综合的层次。 | 难度: 在选择题中属于中等偏上难度，需要理解复合材料力学中的等应变假设，进行多步计算和概念关联。题目要求考生掌握弹性模量的定义、应力-应变关系以及复合材料载荷分配原理，并通过综合分析得出纤维承载比例。虽然题目提供了关键公式，但需要正确应用和转换多个变量关系才能得出最终答案。", "convertible": true, "correct_option": "0.96", "choice_question": "In a glass fiber reinforced nylon composite, the volume fraction of E-glass fiber is 0.3. The elastic moduli of E-glass and nylon are 72.4 GPa and 2.76 GPa, respectively. What is the fraction of the load borne by the fibers in the composite?", "conversion_reason": "The answer is a specific numerical value (0.96), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.96", "B": "0.72", "C": "0.30", "D": "0.48" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the rule of mixtures for load sharing in composites: P_f/P_total = (E_f*V_f)/(E_f*V_f + E_m*V_m) = (72.4*0.3)/(72.4*0.3 + 2.76*0.7) = 0.96. Option B (0.72) is a common error from multiplying the volume fraction by the modulus ratio without proper normalization. Option C (0.30) is a naive answer using just the volume fraction. Option D (0.48) comes from incorrectly averaging the moduli without considering volume fractions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3957, "question": "13: Typical relationship between E and G}\nFor most metals, the relationship between elastic and shear moduli is approximately which of the following?(a) G=0.1 E(b) G=0.2 E(c) G=0.3 E(d) G=0.4 E(e) G=0.5 E", "answer": "the relationship between elastic and shear moduli for most metals is approximately g=0.4 e.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对弹性模量和剪切模量之间关系的基本概念记忆，属于基础知识的直接应用，无需复杂分析或计算。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需直接回忆弹性模量（E）和剪切模量（G）之间的典型关系即可作答，无需复杂理解或分析。", "convertible": true, "correct_option": "d", "choice_question": "For most metals, the relationship between elastic and shear moduli is approximately which of the following?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "G = E/(2(1+ν)) where ν=0.5 (perfectly incompressible material)", "B": "G = E/3 (derived from cubic crystal symmetry assumption)", "C": "G ≈ 0.38E (typical for FCC metals with ν≈0.33)", "D": "G = E/2 (maximum theoretical value for ν=0)" }, "correct_answer": "C", "explanation": "The correct relationship for most polycrystalline metals is G ≈ E/2.6 ≈ 0.38E when Poisson's ratio ν≈0.33. Option A is a trap using the theoretical maximum ν=0.5 case which doesn't occur in real metals. Option B exploits crystal symmetry confusion by applying cubic crystal math to polycrystalline materials. Option D presents the absolute maximum possible value (ν=0 case) which never occurs in metals. All options are mathematically valid under specific conditions, making this a high-difficulty discrimination question.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 816, "question": "Explain the meaning of the rolling texture {110}<112> in face-centered cubic alloy α-brass.", "answer": "It is a sheet texture. The {110}<112> texture indicates that the {110} plane is parallel to the rolling plane, and the <112> direction is parallel to the rolling direction.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释面心立方合金α-黄铜中{110}<112>轧制织构的含义，需要文字解释和论述，答案也是以文字形式详细说明该织构的特征和意义。 | 知识层次: 题目考查对轧制织构{110}<112>的基本概念和定义的理解，属于基础概念的记忆和解释，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并描述{110}<112>滚动织构的具体含义，包括平面和方向的对应关系。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "It is a sheet texture. The {110}<112> texture indicates that the {110} plane is parallel to the rolling plane, and the <112> direction is parallel to the rolling direction.", "choice_question": "Which of the following best explains the meaning of the rolling texture {110}<112> in face-centered cubic alloy α-brass?", "conversion_reason": "The answer is a standard description of a specific texture in materials science, which can be presented as a correct option among other plausible but incorrect descriptions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It is a sheet texture where {110} plane is parallel to the rolling plane and <112> direction is parallel to the rolling direction", "B": "It represents a recrystallization texture where {110} planes align with the annealing direction", "C": "It indicates a wire texture with <112> fiber axis parallel to the drawing direction", "D": "It describes a deformation texture where {110} slip planes are activated during cold rolling" }, "correct_answer": "A", "explanation": "The correct answer is A because {110}<112> is a well-documented sheet texture in FCC metals where the crystallographic plane and direction align with the rolling plane and direction. Option B is incorrect because it confuses rolling texture with recrystallization texture. Option C is a wire texture description which is inappropriate for sheet rolling. Option D incorrectly associates the notation with slip system activation rather than crystallographic orientation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4041, "question": "How do the electrical conductivities of metals compare with those of semiconductors?(a) \\sigma_{\\text {metals }}>\\sigma_{\\text {semiconductors }}(b) \\sigma_{\\text {metals }}=\\sigma_{\\text {semiconductors }}(c) \\sigma_{\\text {metals }}<\\sigma_{\\text {semiconductors }}", "answer": "The electrical conductivities of metals are greater than those of semiconductors.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(a)、(b)、(c)中选择正确答案，符合选择题的特征 | 知识层次: 题目考查的是金属和半导体电导率的基本概念和比较，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型内，该题目仅涉及基础概念记忆，即金属和半导体电导率的比较。学生只需记住金属的电导率通常高于半导体这一基本事实即可正确作答，无需进行复杂的理解或分析。因此，该题目属于简单概念识别和直接记忆的难度等级。", "convertible": true, "correct_option": "(a) \\sigma_{\\text {metals }}>\\sigma_{\\text {semiconductors }}", "choice_question": "How do the electrical conductivities of metals compare with those of semiconductors?", "conversion_reason": "The original question is already in a multiple-choice format with distinct options, and the answer clearly corresponds to one of the provided choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship predicts increased yield strength with decreasing grain size in nanocrystalline materials", "B": "Dislocation density is the primary strengthening mechanism in nanocrystalline materials with grain sizes below 10nm", "C": "Grain boundary sliding becomes the dominant deformation mechanism when grain size exceeds 100nm", "D": "The inverse Hall-Petch effect occurs due to increased dislocation nucleation at grain boundaries below critical grain size" }, "correct_answer": "D", "explanation": "The correct answer is D because the inverse Hall-Petch effect is a well-documented phenomenon where materials soften below a critical grain size (~10-20nm) due to grain boundary sliding and reduced dislocation activity. Option A is incorrect because the classical Hall-Petch relationship breaks down at nanoscale. Option B is a trap exploiting the common misconception that dislocations remain important below 10nm, when in fact grain boundary mechanisms dominate. Option C reverses the grain size condition for grain boundary sliding dominance, which actually occurs below 100nm.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4063, "question": "[c] Aluminum alloys are generally superior to pure aluminum, in terms of yield strength, because their microstructures often contain precipitate phases that strain the lattice, thereby hardening the alloy relative to pure aluminum.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性（答案T表示正确），这是典型的判断题特征。题目没有提供多个选项、不需要计算或文字解释，完全符合判断题的定义。 | 知识层次: 题目考查铝合金相对于纯铝的强化机制的基本概念，涉及沉淀相和晶格应变的基础知识，属于基础概念的记忆和理解层次。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目陈述了一个关于铝合金相对于纯铝的优势的基础事实，即由于沉淀相的存在导致晶格应变从而硬化合金。正确选项直接对应这一基础概念的陈述，无需深入理解或分析多个概念。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "T", "choice_question": "[c] Aluminum alloys are generally superior to pure aluminum, in terms of yield strength, because their microstructures often contain precipitate phases that strain the lattice, thereby hardening the alloy relative to pure aluminum.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All precipitation-hardened aluminum alloys will always exhibit higher yield strength than pure aluminum under all temperature conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While precipitation hardening generally increases yield strength in aluminum alloys, this is not universally true under all conditions. At elevated temperatures, precipitate phases may dissolve or coarsen, reducing their strengthening effect. Some specialized pure aluminum forms (like single crystals) can also achieve exceptional strength. The absolute term 'always' makes this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1594, "question": "1. What is aging treatment?", "answer": "The process of treating the precipitation of a supersaturated solid solution is called aging treatment.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"aging treatment\"进行文字解释和论述，答案提供了详细的定义说明，符合简答题的特征 | 知识层次: 题目考查对\"aging treatment\"这一基本概念的定义记忆和理解，属于材料科学中的基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察对\"aging treatment\"基础定义的记忆，属于最简单的定义简答类型。正确选项直接给出了术语的标准定义，不需要任何解释、分析或推理过程，完全符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "The process of treating the precipitation of a supersaturated solid solution is called aging treatment.", "choice_question": "What is aging treatment?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A process to accelerate precipitation hardening by heating above solvus temperature", "B": "The process of treating the precipitation of a supersaturated solid solution", "C": "A method to improve ductility by reducing dislocation density through annealing", "D": "A surface treatment technique to enhance corrosion resistance through oxide layer formation" }, "correct_answer": "B", "explanation": "The correct answer is B because aging treatment specifically refers to the controlled precipitation process in supersaturated solid solutions. Option A is a cognitive bias trap - it describes solution treatment rather than aging. Option C exploits professional intuition by mixing aging with annealing concepts. Option D is a multi-level trap combining surface treatment with precipitation hardening terminology.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2781, "question": "Calculate the diffusion coefficient D of carbon in γ-Fe. Given the diffusion coefficient of carbon in γ-Fe D₀=2.0×10⁻⁵ m²/s, activation energy Q=142 kJ/mol, and temperature T=1000℃.", "answer": "D=D₀e^(−Q/RT)=2.0×10⁻⁵×exp(−142000/(8.314×1273))=2.98×10⁻¹¹ m²/s", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出扩散系数D的具体数值。答案是一个具体的计算结果，符合计算题的特征。 | 知识层次: 题目要求直接应用扩散系数的计算公式，涉及基本的数值计算和公式套用，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要套用扩散系数的阿伦尼乌斯公式，但题目已经提供了所有必要的参数（D₀、Q、T），且计算过程仅涉及基本代数运算和指数函数的应用。不需要额外的推导或复杂转换，属于直接套用公式即可解决的题目。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "2.98×10⁻¹¹ m²/s", "choice_question": "Calculate the diffusion coefficient D of carbon in γ-Fe. Given the diffusion coefficient of carbon in γ-Fe D₀=2.0×10⁻⁵ m²/s, activation energy Q=142 kJ/mol, and temperature T=1000℃.", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.98×10⁻¹¹ m²/s", "B": "1.42×10⁻⁵ m²/s", "C": "2.0×10⁻⁵ m²/s", "D": "1.42×10⁻¹¹ m²/s" }, "correct_answer": "A", "explanation": "正确答案A是通过阿伦尼乌斯方程D=D₀exp(-Q/RT)正确计算得出，其中温度需转换为开尔文(1273K)，R=8.314 J/(mol·K)。干扰项B直接使用了激活能量数值但忽略了指数关系，利用了'数值看起来合理'的认知偏差。干扰项C直接给出D₀值，利用了'忽略温度影响'的常见错误直觉。干扰项D结合了激活能量和正确答案的数量级，设计了需要同时验证单位和数值的双重陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3071, "question": "What is wood composed of?", "answer": "(1) Cellulose; (2) Lignin", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答木材的组成成分，答案以列举形式给出，需要简要说明而非选择或判断 | 知识层次: 题目考查木材的基本组成成分，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆木材的基本组成成分（纤维素和木质素），属于基础概念记忆层次。题目仅涉及简单的定义和分类，无需解释或复杂分析，因此难度等级为1。", "convertible": true, "correct_option": "Cellulose; Lignin", "choice_question": "What are the main components of wood?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by listing the components as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cellulose and lignin", "B": "Cellulose and hemicellulose", "C": "Lignin and pectin", "D": "Hemicellulose and pectin" }, "correct_answer": "A", "explanation": "The correct answer is A because wood is primarily composed of cellulose (providing structural strength) and lignin (providing rigidity and resistance to compression). Option B is incorrect because while hemicellulose is present, it is not a main component like lignin. Option C is incorrect because pectin is not a significant component of wood. Option D is incorrect for the same reason, as neither hemicellulose nor pectin are main components compared to cellulose and lignin.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3602, "question": "A typical paper clip weighs 0.59g and consists of BCC iron. Calculate the number of unit cells in the paper clip.", "answer": "3.185 × 10^21 cells", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算纸夹中的晶胞数量），需要使用公式和给定的物理量（质量和晶体结构），最终给出一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括质量到摩尔数的转换、BCC结构中原子的计算以及单位晶胞数量的确定，涉及多个概念的综合应用和关联。 | 难度: 在选择题中属于中等偏上难度，需要综合运用多个概念并进行多步计算。具体包括：1) 理解BCC铁的单位细胞结构；2) 计算单位细胞的质量；3) 将纸夹总质量转换为单位细胞数量。虽然题目给出了正确选项，但解题过程涉及单位换算、晶体结构知识和数学运算，比简单记忆或单一概念的选择题更复杂。", "convertible": true, "correct_option": "3.185 × 10^21 cells", "choice_question": "A typical paper clip weighs 0.59g and consists of BCC iron. The number of unit cells in the paper clip is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.185 × 10^21 cells", "B": "1.592 × 10^21 cells", "C": "6.370 × 10^21 cells", "D": "4.778 × 10^21 cells" }, "correct_answer": "A", "explanation": "The correct answer is calculated by first determining the number of iron atoms in the paper clip (0.59g / 55.85 g/mol × 6.022 × 10^23 atoms/mol = 6.370 × 10^21 atoms), then dividing by 2 since BCC iron has 2 atoms per unit cell. Option B is half the correct value, exploiting the common mistake of forgetting to divide by 2 for BCC structure. Option C is the total number of atoms, not unit cells, targeting confusion between these concepts. Option D is 75% of the correct value, designed to catch those who incorrectly account for packing efficiency.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1454, "question": "After cold plastic deformation of metal, its plasticity and toughness (41)", "answer": "decrease", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要回答金属冷塑性变形后其塑性和韧性的变化，答案是一个简短的描述性词语\"decrease\"，属于需要文字解释的简答题类型 | 知识层次: 题目考查金属冷塑性变形后塑性和韧性的变化这一基础概念的记忆和理解，属于材料科学中的基本原理知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对金属冷塑性变形后性能变化的基础概念记忆，属于最基础的定义性知识。学生只需记住\"冷变形会导致塑性和韧性下降\"这一简单事实即可作答，无需任何解释或分析步骤。", "convertible": true, "correct_option": "decrease", "choice_question": "After cold plastic deformation of metal, its plasticity and toughness:", "conversion_reason": "简答题的答案是标准术语，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Decrease due to dislocation entanglement and strain hardening", "B": "Increase as dislocations rearrange into lower-energy configurations", "C": "Remain unchanged as the crystal structure is preserved", "D": "Initially increase then decrease with further deformation" }, "correct_answer": "A", "explanation": "The correct answer is A because cold working introduces dislocations that become entangled, leading to strain hardening which reduces plasticity and toughness. Option B exploits the cognitive bias that dislocations might rearrange favorably, while actually they increase internal stresses. Option C uses the false intuition that visible shape change implies preserved microstructure. Option D creates a multi-stage verification trap by mimicking typical stress-strain behavior but misapplying it to material properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2182, "question": "Explain why crystal slip usually occurs on the most closely packed atomic planes and directions.", "answer": "As can be seen from the relation, the larger the value of a, the smaller the τ_p, so the slip plane should be the one with the largest interplanar spacing, i.e., the most closely packed atomic plane; the smaller the value of b, the smaller the τ_p, so the slip direction should be the most closely packed atomic direction.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释晶体滑移通常发生在最密排原子面和方向的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释晶体滑移通常发生在最密排原子面和方向的原因，涉及对晶体结构、滑移机制和临界分切应力等概念的深入理解和综合分析。需要运用相关理论进行推理和解释，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解晶体滑移的基本概念，还需要综合运用材料科学中的多个原理（如晶面间距与临界分切应力的关系、原子密排方向与滑移难易度的关系）进行深度推理分析。正确选项涉及对复杂材料现象的全面解释，需要考生具备将理论公式（τ_p与a、b的关系）与晶体结构实际特征（密排面/方向）联系起来的能力，这远超选择题常见的简单记忆或基础应用层次。", "convertible": true, "correct_option": "As can be seen from the relation, the larger the value of a, the smaller the τ_p, so the slip plane should be the one with the largest interplanar spacing, i.e., the most closely packed atomic plane; the smaller the value of b, the smaller the τ_p, so the slip direction should be the most closely packed atomic direction.", "choice_question": "Why does crystal slip usually occur on the most closely packed atomic planes and directions?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The most closely packed planes have the highest elastic modulus, making them more resistant to deformation", "B": "Slip occurs where the Burgers vector is minimized, which coincides with the most closely packed directions", "C": "The highest atomic density planes require the least energy for dislocation movement due to maximum interplanar spacing", "D": "Close-packed directions have the lowest surface energy, facilitating dislocation glide" }, "correct_answer": "C", "explanation": "Correct answer C combines two key factors: maximum interplanar spacing (reducing lattice resistance) and atomic density (minimizing dislocation core energy). Option A misapplies elastic modulus to slip systems. Option B incorrectly reverses the Burgers vector relationship. Option D confuses surface energy with dislocation line energy. These traps exploit common material science misconceptions about modulus-energy relationships and vector mechanics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4720, "question": "Molybdenum (Mo) forms a substitutional solid solution with tungsten (W). Compute the number of molybdenum atoms per cubic centimeter for a molybdenum-tungsten alloy that contains 16.4 wt% Mo and 83.6 wt% W. The densities of pure molybdenum and tungsten are 10.22 and 19.30g / {cm}^{3}, respectively.", "answer": "1.73 × 10^{22} \\text{ atoms/cm}^3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算钼原子数每立方厘米），涉及公式应用（如密度、质量分数转换等），答案也是具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括质量分数转换为原子分数、计算合金密度、以及最终计算原子数量，涉及多个概念的综合应用和关联分析。 | 难度: 在选择题中属于中等偏上难度，需要理解固溶体、原子百分比与重量百分比的转换、密度计算等多个概念，并进行多步骤的综合计算。虽然题目给出了正确选项，但解题过程涉及多个知识点的关联和综合运用，属于综合性计算问题。", "convertible": true, "correct_option": "1.73 × 10^{22} atoms/cm^3", "choice_question": "Molybdenum (Mo) forms a substitutional solid solution with tungsten (W). Compute the number of molybdenum atoms per cubic centimeter for a molybdenum-tungsten alloy that contains 16.4 wt% Mo and 83.6 wt% W. The densities of pure molybdenum and tungsten are 10.22 and 19.30g/cm^3, respectively.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.73 × 10^{22} atoms/cm^3", "B": "2.45 × 10^{22} atoms/cm^3", "C": "1.02 × 10^{22} atoms/cm^3", "D": "3.14 × 10^{22} atoms/cm^3" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算得到的：首先计算合金密度(ρ_alloy = 1/(0.164/10.22 + 0.836/19.30) = 17.14 g/cm^3)，然后计算Mo的原子浓度(0.164×17.14×6.022×10^{23}/95.94 = 1.73×10^{22} atoms/cm^3)。干扰项B错误地使用了纯Mo的密度直接计算，忽略了合金效应。干扰项C错误地使用了原子百分比而非重量百分比进行计算。干扰项D是随机生成的高数值，利用了对大数缺乏敏感性的认知偏差。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4016, "question": "Is solid lead-tin solder (a mixture of Pb-rich and Sn-rich solid solutions) a two-phase material system?", "answer": "Yes, it is a two-phase system because there is a physical boundary beyond the particle level that separates chemically and structurally distinct volumes.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（\"Is solid lead-tin solder... a two-phase material system?\"），答案明确给出了\"Yes\"的判断并提供了简要解释，符合判断题的特征。 | 知识层次: 题目考查对两相材料系统基本概念的记忆和理解，涉及简单的分类判断，不需要复杂的分析或计算。 | 难度: 该题目属于基本概念正误判断，仅需记忆和识别\"两相材料系统\"的定义即可作答。题目直接考察对铅锡焊料相组成的记忆性知识，无需复杂推理或概念比较，在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "Yes, it is a two-phase system because there is a physical boundary beyond the particle level that separates chemically and structurally distinct volumes.", "choice_question": "Is solid lead-tin solder (a mixture of Pb-rich and Sn-rich solid solutions) a two-phase material system?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All solid solutions are single-phase materials by definition.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most solid solutions are single-phase, some like lead-tin solder can form two-phase systems when they consist of distinct Pb-rich and Sn-rich solid solution regions with physical boundaries. The absolute term 'all' makes this statement false.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1022, "question": "Given that for carbon diffusion in γ-Fe, D0=2.0×10^(-5)m²/s, Q=1.4×10^5J/mol, gas constant R=8.314J/(mol·K), calculate the diffusion coefficient D1027°C at 1027°C.", "answer": "D1027°C = D0 * exp(-Q / (R * T)) = 2.0×10^(-5) * exp(-1.4×10^5 / (8.314 * (1027 + 273))) = 2.0×10^(-5) * exp(-1.4×10^5 / (8.314 * 1300)) = 2.0×10^(-5) * exp(-12.953) ≈ 2.0×10^(-5) * 2.394×10^(-6) ≈ 4.788×10^(-11) m²/s", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出扩散系数的具体数值，属于典型的计算题。 | 知识层次: 题目主要考查对扩散系数公式的直接应用和简单计算，涉及温度单位的转换和指数运算，但不需要多步推理或综合分析。 | 难度: 在选择题中属于简单难度，题目仅涉及单一公式的直接应用和简单计算，无需多个公式组合或复杂分析。学生只需正确代入给定数值到阿伦尼乌斯方程中并进行指数运算即可得出结果。", "convertible": true, "correct_option": "4.788×10^(-11) m²/s", "choice_question": "Given that for carbon diffusion in γ-Fe, D0=2.0×10^(-5)m²/s, Q=1.4×10^5J/mol, gas constant R=8.314J/(mol·K), calculate the diffusion coefficient D at 1027°C.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.788×10^(-11) m²/s", "B": "1.327×10^(-11) m²/s", "C": "2.394×10^(-11) m²/s", "D": "9.576×10^(-11) m²/s" }, "correct_answer": "A", "explanation": "正确答案A通过Arrhenius方程D=D0*exp(-Q/RT)精确计算得出。干扰项B错误地将温度单位保留为摄氏度而非转换为开尔文。干扰项C是正确答案的一半，利用了计算过程中可能出现的系数错误。干扰项D是正确答案的两倍，利用了指数计算中常见的乘法误差。这些干扰项都针对AI在单位转换、指数运算和系数处理上的潜在弱点设计。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3318, "question": "Compare the approximate diffusion distances/mm of carbon atoms during bainitic transformation, pearlitic transformation, and martensitic transformation", "answer": "In pearlitic transformation, the diffusion distance of carbon atoms is greater than 10mm; in bainitic transformation, the diffusion distance of carbon atoms is 0~10mm; in martensitic transformation, the diffusion distance of carbon atoms is 0mm.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对不同相变过程中碳原子的扩散距离进行比较和解释，答案以文字形式详细描述了不同相变过程中的扩散距离范围，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求比较不同相变过程中碳原子的扩散距离，涉及对珠光体、贝氏体和马氏体相变过程的理解，需要综合分析不同相变机制对碳原子扩散的影响。虽然不涉及复杂计算，但需要对多个概念进行关联和比较，思维过程有一定深度。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生比较碳原子在不同相变过程中的扩散距离，涉及对珠光体转变、贝氏体转变和马氏体转变的理解。虽然题目提供了正确选项，但考生仍需掌握这些相变的基本特征和扩散机制，才能正确判断和比较扩散距离。这需要中等层次的知识应用能力，包括概念关联和综合分析。", "convertible": true, "correct_option": "In pearlitic transformation, the diffusion distance of carbon atoms is greater than 10mm; in bainitic transformation, the diffusion distance of carbon atoms is 0~10mm; in martensitic transformation, the diffusion distance of carbon atoms is 0mm.", "choice_question": "Compare the approximate diffusion distances/mm of carbon atoms during bainitic transformation, pearlitic transformation, and martensitic transformation. Which of the following statements is correct?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question by presenting the answer as one of the options and rephrasing the question to fit the multiple-choice format. The answer is a specific and standard description of the diffusion distances, making it suitable for conversion.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In pearlitic transformation, the diffusion distance of carbon atoms is greater than 10mm; in bainitic transformation, the diffusion distance of carbon atoms is 0~10mm; in martensitic transformation, the diffusion distance of carbon atoms is 0mm", "B": "In pearlitic transformation, the diffusion distance of carbon atoms is 0~10mm; in bainitic transformation, the diffusion distance of carbon atoms is greater than 10mm; in martensitic transformation, the diffusion distance of carbon atoms is 0mm", "C": "In pearlitic transformation, the diffusion distance of carbon atoms is 0mm; in bainitic transformation, the diffusion distance of carbon atoms is 0~10mm; in martensitic transformation, the diffusion distance of carbon atoms is greater than 10mm", "D": "All three transformations involve carbon diffusion distances greater than 10mm due to high temperature conditions" }, "correct_answer": "A", "explanation": "The correct answer is A because pearlite forms at higher temperatures allowing long-range carbon diffusion (>10mm), bainite forms at intermediate temperatures with limited diffusion (0-10mm), and martensite forms via diffusionless transformation (0mm). Option B reverses pearlite and bainite distances, exploiting confusion about intermediate vs high temperature behavior. Option C incorrectly assigns the longest diffusion to martensite, targeting misunderstanding of diffusionless transformation. Option D is a blanket statement exploiting the common misconception that all phase transformations involve significant diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 429, "question": "4.The expression for the relationship between the diffusion coefficient, diffusion activation energy, and diffusion temperature is (10)", "answer": "D=D0exp(-Q/RT)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求写出扩散系数、扩散激活能和扩散温度之间关系的表达式，需要直接给出公式作为答案，属于简答题类型 | 知识层次: 题目考查扩散系数与活化能及温度关系的基本公式记忆，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆扩散系数、扩散激活能和扩散温度之间的基本关系表达式，属于基础概念记忆的简单题目。无需解释或分析，只需识别正确选项即可。", "convertible": true, "correct_option": "D=D0exp(-Q/RT)", "choice_question": "4. The expression for the relationship between the diffusion coefficient, diffusion activation energy, and diffusion temperature is:", "conversion_reason": "The answer is a standard mathematical expression, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "D = D0 * exp(-Q/kT)", "B": "D = D0 * exp(-Q/RT)", "C": "D = D0 * ln(Q/RT)", "D": "D = D0 * (Q/RT)^2" }, "correct_answer": "B", "explanation": "正确答案B是阿伦尼乌斯方程的经典形式，其中R是气体常数。干扰项A使用玻尔兹曼常数k而非R，利用了热力学常数混淆策略。干扰项C采用对数形式，利用了数学表达式相似性陷阱。干扰项D设计为幂函数关系，利用了非指数型温度依赖的直觉误导。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3914, "question": "Which crystal system(s) listed below has (have) the following relationship for the unit cell edge lengths?\n\\[\na=b=c\n\\](a) Cubic(b) Hexagonal(c) Tetragonal(d) Rhombohedral(e) Orthorhombic(f) Monoclinic(g) Triclinic", "answer": "For both cubic and rhombohedral crystal systems all the unit cell edge lengths are equal.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择符合特定条件的晶体系统，答案也是从给定的选项中选择的。 | 知识层次: 题目考查对晶体系统基本概念的记忆和理解，特别是对立方和菱方晶系单元边长关系的识别。 | 难度: 在选择题型内，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生对晶体系统的定义和分类有一定的理解和辨析能力。题目要求考生识别哪些晶体系统的晶胞边长满足a=b=c的关系，这需要考生不仅记住各个晶体系统的特点，还需要进行简单的比较和分析。因此，相较于直接记忆的简单概念识别（等级1），该题目更偏向于概念理解和简单辨析（等级2）。", "convertible": true, "correct_option": "a, d", "choice_question": "Which crystal system(s) listed below has (have) the following relationship for the unit cell edge lengths?\n\n\\[\na=b=c\n\\]", "conversion_reason": "原题目已经是选择题格式，且答案明确指出了正确选项（a和d），因此可以转换为单选题格式。转换后的题目保持原样，正确选项为a和d。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项B", "B": "选项D", "C": "a, d", "D": "选项C" }, "correct_answer": "C", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1770, "question": "10. What type of solid solution can albite Na(AlSi3O8) and anorthite Ca(Al2Si2O8) form?", "answer": "Continuous substitutional solid solution", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释albite和anorthite能形成哪种类型的固溶体，答案需要文字描述（Continuous substitutional solid solution），而不是从多个选项中选择或进行数值计算。 | 知识层次: 题目需要理解固溶体的类型及其形成条件，并能够将这一概念应用到具体的矿物体系中（钠长石和钙长石）。这涉及到对固溶体分类的理解以及矿物化学组成的分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解固溶体的基本概念，并能区分不同类型固溶体的特征。题目涉及两种矿物（钠长石和钙长石）的固溶体形成，要求考生掌握连续置换型固溶体的特点，并能将这一概念应用到具体矿物体系中。虽然不需要复杂的计算，但需要对相关概念有清晰的理解和正确的应用。", "convertible": true, "correct_option": "Continuous substitutional solid solution", "choice_question": "What type of solid solution can albite Na(AlSi3O8) and anorthite Ca(Al2Si2O8) form?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Continuous substitutional solid solution", "B": "Interstitial solid solution", "C": "Limited substitutional solid solution", "D": "Intermetallic compound" }, "correct_answer": "A", "explanation": "The correct answer is A because albite and anorthite form a complete solid solution series (plagioclase series) where Na+ and Ca2+ can substitute for each other continuously. Option B is incorrect because interstitial solutions involve smaller atoms fitting into crystal lattice voids, which doesn't apply here. Option C is a strong distractor because many solid solutions have limited solubility, but this is an exceptional case of complete solubility. Option D exploits the common misconception that different cations would form intermetallic compounds rather than solutions, despite these being oxide minerals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 877, "question": "Determine whether the following dislocation reaction can occur in FCC and confirm the reaction direction in the absence of external force: 1/6[112]+1/6[110]⇔1/3[111]", "answer": "It can occur, to the left.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断位错反应是否可以在FCC中发生，并确认反应方向，答案给出了明确的判断（可以发生）和方向（向左），属于判断陈述的对错类型。 | 知识层次: 题目需要理解位错反应的基本原理，并能够应用这些原理来判断反应的方向和可能性。这涉及到多步分析和概念关联，而不仅仅是简单的记忆或直接套用公式。 | 难度: 在选择题型中，该题目需要综合分析位错反应的能量条件和方向判断，涉及多步计算和概念关联，属于中等应用层次。需要考生不仅理解位错反应的基本原理，还要能够应用这些原理进行具体分析，判断反应的方向和可能性。这种综合分析能力的要求使得该题目在选择题型中属于较高难度等级。", "convertible": true, "correct_option": "It can occur, to the left.", "choice_question": "Determine whether the following dislocation reaction can occur in FCC and confirm the reaction direction in the absence of external force: 1/6[112]+1/6[110]⇔1/3[111]", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In FCC crystals, all dislocation reactions that satisfy the Burgers vector conservation rule will spontaneously occur without external stress.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While Burgers vector conservation is necessary for dislocation reactions, it is not sufficient. The reaction must also reduce the total elastic energy of the system to occur spontaneously. Many reactions that conserve Burgers vectors are energetically unfavorable and require external stress to proceed.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4048, "question": "For a p-type semiconductor, which type of charge carrier is present in the greater concentration?(a) Holes(b) Electrons", "answer": "For a p-type semiconductor, holes, (i.e., positive charge carriers) are present in a greater concentration than electrons.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的两个选项（a）Holes和（b）Electrons中选择正确答案，符合选择题的特征。 | 知识层次: 题目考查对p型半导体中主要载流子类型的基础概念记忆，仅需知道p型半导体中空穴浓度高于电子这一基本事实即可回答，无需复杂分析或计算。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即p型半导体中多数载流子的类型。学生只需直接回忆p型半导体的定义即可选出正确答案，无需进行复杂的概念辨析或深度理解。因此，该题目属于简单概念识别，直接记忆的难度等级。", "convertible": true, "correct_option": "Holes", "choice_question": "For a p-type semiconductor, which type of charge carrier is present in the greater concentration?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly identifies the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Holes", "B": "Electrons", "C": "Equal concentration of both", "D": "Depends on the dopant concentration" }, "correct_answer": "A", "explanation": "The correct answer is A because in p-type semiconductors, holes are the majority charge carriers due to the acceptor dopants creating excess holes. Option B is incorrect but may seem plausible because electrons are still present as minority carriers. Option C is a cognitive bias trap, as it suggests an intrinsic semiconductor behavior which doesn't apply to doped materials. Option D is a professional intuition trap, as while dopant concentration affects carrier density, it doesn't change the fundamental fact that holes remain the majority carriers in p-type materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2113, "question": "Point out the errors in the following concept and correct them: For an alloy with peritectic transformation, the phase constituents at room temperature are α + β, where all β phases are products of peritectic transformation.", "answer": "The β phase should include the products of peritectic reaction, those formed by homogeneous transformation, and secondary β phases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。答案也以文字形式呈现，解释了β相的来源，符合简答题的特征。 | 知识层次: 题目要求识别并纠正关于合金相变的概念错误，涉及对相变过程的理解和相组成的综合分析，需要将基础概念与实际相变过程关联起来进行判断和解释。 | 难度: 在选择题中属于较高难度，需要考生不仅理解相图的基本概念，还需要掌握包晶转变的具体过程及其产物。题目要求考生能够区分不同来源的β相（包晶反应产物、均匀转变产物和次生β相），并进行多角度分析。这涉及到对相变过程的深入理解和综合分析能力，超出了简单的概念记忆或单一知识点的应用。", "convertible": true, "correct_option": "The β phase should include the products of peritectic reaction, those formed by homogeneous transformation, and secondary β phases.", "choice_question": "Which of the following correctly describes the phase constituents at room temperature for an alloy with peritectic transformation, where the phase constituents are α + β?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question by rephrasing it to ask for the correct description of the phase constituents. The answer provided is a standard concept that can be used as the correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The β phase includes only the products of peritectic reaction", "B": "The β phase includes only secondary β phases formed during cooling", "C": "The β phase includes both peritectic reaction products and secondary β phases", "D": "The β phase includes peritectic reaction products, homogeneous transformation products, and secondary β phases" }, "correct_answer": "D", "explanation": "The correct answer is D because in peritectic systems, the β phase at room temperature includes: 1) primary β formed by peritectic reaction, 2) β formed by homogeneous transformation from high-temperature phases, and 3) secondary β precipitated during cooling. Option A is a cognitive bias trap, appealing to the oversimplified view that β only comes from peritectic reaction. Option B is a professional intuition trap, focusing only on the most obvious cooling transformation. Option C is a multi-level verification trap that seems correct but misses the homogeneous transformation products.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 450, "question": "What effect does a rough interface have on the crystal growth mode?", "answer": "For a rough interface, continuous growth occurs.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释粗糙界面对晶体生长模式的影响，答案提供了简短的文字解释，符合简答题的特征。 | 知识层次: 题目考查晶体生长模式的基本概念，特别是粗糙界面对生长模式的影响，属于基本原理的记忆和理解范畴。 | 难度: 在选择题型中，该题目仅考察对粗糙界面与晶体生长模式关系的基础定义记忆，属于最基础的概念性知识，无需解释或分析步骤。", "convertible": true, "correct_option": "continuous growth occurs", "choice_question": "What effect does a rough interface have on the crystal growth mode?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "continuous growth occurs", "B": "layer-by-layer growth dominates", "C": "step flow mechanism initiates", "D": "two-dimensional nucleation increases" }, "correct_answer": "A", "explanation": "A rough interface provides numerous active sites for atom attachment, leading to continuous growth (A). B is incorrect because it describes the growth mode for smooth interfaces. C is a trap for those confusing rough interfaces with vicinal surfaces. D exploits the common misconception that nucleation events increase with interface roughness.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4848, "question": "Germanium to which 10^24 m^-3 As atoms have been added is an extrinsic semiconductor at room temperature, and virtually all the As atoms may be thought of as being ionized (i.e., one charge carrier exists for each As atom). Calculate the electrical conductivity of this material, assuming electron and hole mobilities of 0.1 and 0.05 m^2/V-s, respectively.", "answer": "the conductivity is equal to 1.60 × 10^4 (ω·m)^-1.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解锗材料的电导率，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过给定的掺杂浓度和载流子迁移率直接计算电导率。虽然需要理解半导体掺杂和载流子迁移的概念，但计算过程较为直接，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算掺杂锗的电导率，只需应用电导率的基本公式σ = n * e * μ（其中n为载流子浓度，e为电子电荷，μ为载流子迁移率），并将给定的数值直接代入即可得到结果。无需多个公式组合或复杂分析，属于最基础的计算题。", "convertible": true, "correct_option": "1.60 × 10^4 (ω·m)^-1", "choice_question": "Germanium to which 10^24 m^-3 As atoms have been added is an extrinsic semiconductor at room temperature, and virtually all the As atoms may be thought of as being ionized (i.e., one charge carrier exists for each As atom). Calculate the electrical conductivity of this material, assuming electron and hole mobilities of 0.1 and 0.05 m^2/V-s, respectively. The conductivity is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option is the provided conductivity value.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.60 × 10^4 (ω·m)^-1", "B": "3.20 × 10^4 (ω·m)^-1", "C": "8.00 × 10^3 (ω·m)^-1", "D": "1.28 × 10^5 (ω·m)^-1" }, "correct_answer": "A", "explanation": "The correct answer is A (1.60 × 10^4 (ω·m)^-1) because the conductivity (σ) is calculated using the formula σ = n|e|μ_e, where n is the carrier concentration (10^24 m^-3), e is the electron charge (1.6 × 10^-19 C), and μ_e is the electron mobility (0.1 m^2/V-s). The hole contribution is negligible in this n-type semiconductor. Option B doubles the correct value, exploiting the common mistake of adding electron and hole contributions. Option C is half the correct value, targeting those who might incorrectly average the mobilities. Option D is an order of magnitude higher, preying on unit conversion errors or decimal misplacement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2992, "question": "Due to the very long molecular chains, how is the relationship between secondary valence forces and primary valence forces often?", "answer": "Greater than", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释分子链长度对次级价力和主价力关系的影响，需要文字论述而非选择或判断 | 知识层次: 题目考查对高分子链中次级价力与主价力关系的基本概念记忆和理解，属于基础概念层次。 | 难度: 该题目属于基础概念记忆层次，仅需要考生记住高分子材料中次级价力与主价力的基本关系。在选择题型中，只需识别正确选项\"Greater than\"，无需复杂推理或概念比较，属于最简单的定义性知识考查。", "convertible": true, "correct_option": "Greater than", "choice_question": "Due to the very long molecular chains, how is the relationship between secondary valence forces and primary valence forces often?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Greater than", "B": "Equal to", "C": "Less than", "D": "Inversely proportional to" }, "correct_answer": "A", "explanation": "The correct answer is A because in polymers with very long molecular chains, the cumulative effect of secondary valence forces (van der Waals, hydrogen bonds) often exceeds the strength of individual primary valence (covalent) bonds. Option B is a common misconception from small molecule chemistry where secondary forces are typically weaker. Option C exploits the intuitive but incorrect assumption that covalent bonds are always stronger. Option D is a structural trap suggesting a mathematical relationship that doesn't exist in this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 414, "question": "For a carbon steel containing 0.1% carbon, carburized at 930‰, the carburized layer thickness is 0.4mm after 3 hours. Someone wants to obtain a 0.8mm carburized layer and plans to use 6 hours. Is this person's plan correct? Why?", "answer": "$$ c{\\left(\\begin{array}{l l}{x,t}\\end{array}\\right)}=c_{1}+{\\left(\\begin{array}{l}{c_{8}-c_{1}}\\end{array}\\right)}{\\left(1-\\operatorname{erf}{\\frac{x}{2{\\sqrt{D t}}}}\\right)} $$ According to the problem, $c(\\textit{x}_{1},\\textit{t}_{1})=c(\\textit{x}_{2},\\textit{t}_{2})c_{s}$, and $c_{1}$ is a constant. Therefore, $$ \\operatorname{erf}{\\frac{x_{1}}{2{\\sqrt{D t_{1}}}}}=\\operatorname{erf}{\\frac{x_{2}}{2{\\sqrt{D t_{2}}}}} $$ Hence, $$ {\\frac{x_{1}}{2{\\sqrt{D t_{1}}}}}={\\frac{x_{2}}{2{\\sqrt{D t_{2}}}}}\\quad{\\frac{x_{1}}{\\sqrt{t_{1}}}}={\\frac{x_{2}}{\\sqrt{t_{2}}}},\\quad{\\frac{0.4}{\\sqrt{3}}}={\\frac{0.8}{\\sqrt{t_{2}}}} $$ $$ t_{2}={\\left({\\frac{0.8}{0.4}}\\times{\\sqrt{3}}\\right)}^{2}\\mathbf{h}=12\\mathbf{h} $$ Thus, the person's plan is incorrect.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来解决问题，答案中包含了具体的数学推导和计算过程，最终得出一个明确的数值结果。 | 知识层次: 题目需要应用扩散方程和误差函数进行多步计算，涉及碳浓度分布公式的理解和推导，需要将实际问题转化为数学模型并进行求解，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程的应用，并能够正确运用误差函数进行多步计算。题目要求考生将理论公式与实际问题相结合，通过数学推导得出正确结论。虽然题目提供了关键公式，但需要考生具备综合分析能力，能够正确建立变量关系并完成计算步骤。", "convertible": true, "correct_option": "Incorrect, because the required time should be 12 hours instead of 6 hours.", "choice_question": "For a carbon steel containing 0.1% carbon, carburized at 930‰, the carburized layer thickness is 0.4mm after 3 hours. Someone wants to obtain a 0.8mm carburized layer and plans to use 6 hours. Is this person's plan correct?", "conversion_reason": "The problem involves a calculation with a definitive answer, making it suitable for conversion into a multiple-choice question. The correct option can be derived from the mathematical solution provided.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Incorrect, because the required time should be 12 hours instead of 6 hours", "B": "Correct, because carburization depth is directly proportional to time", "C": "Incorrect, because the required time should be 9 hours due to temperature effects", "D": "Correct, because doubling the thickness requires quadrupling the time" }, "correct_answer": "A", "explanation": "The correct answer is A because carburization depth follows a square root relationship with time (d ∝ √t). To double the depth from 0.4mm to 0.8mm, time must quadruple from 3 to 12 hours. Option B is a cognitive bias trap, appealing to the false intuition of direct proportionality. Option C is a professional intuition trap, introducing a plausible but irrelevant temperature factor. Option D is a multi-level verification trap, correctly identifying the non-linear relationship but reversing the mathematical operation (quadrupling time instead of depth).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3037, "question": "The basic raw materials of traditional ceramics are (1), (2), and (3), and its structure is composed of (4), (5), and (6).", "answer": "(1) clay; (2) quartz; (3) feldspar; (4) crystalline phase; (5) glass phase; (6) gas phase", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的材料名称和结构组成，需要文字回答而非选择或判断 | 知识层次: 题目考查传统陶瓷的基本原料和结构组成，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 该题目属于基础概念记忆类型，仅需回忆传统陶瓷的基本原料和结构组成。在选择题型中，题目直接给出了正确选项，无需进行复杂的概念比较或分析。学生只需记住粘土、石英、长石这三种原料，以及晶相、玻璃相、气相这三种结构组成即可。这种题目在选择题中属于最简单的难度等级，主要考察学生对基础知识的记忆能力。", "convertible": true, "correct_option": "clay, quartz, feldspar, crystalline phase, glass phase, gas phase", "choice_question": "The basic raw materials of traditional ceramics and its structure are composed of which of the following combinations?", "conversion_reason": "The answer consists of standard terms and concepts that can be presented as options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "correct_answer": "A", "explanation": "The correct answer A uses the most precise terminology: ", "options": { "A": "clay, quartz, feldspar / crystalline phase, glass phase, gas phase", "B": "kaolin, silica, alumina / crystalline phase, amorphous phase, voids", "C": "clay, silica, feldspar / crystalline phase, vitreous phase, porosity", "D": "kaolin, quartz, feldspar / crystalline domains, glassy matrix, pores" }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4744, "question": "For a brass alloy, the stress at which plastic deformation begins is 345 MPa (50,000 psi), and the modulus of elasticity is 103 GPa (15.0 x 10^6 psi). What is the maximum load that can be applied to a specimen with a cross-sectional area of 130 mm^2 (0.2 in.^2) without plastic deformation?", "answer": "the maximum load that can be applied without plastic deformation is 44,850 n (10,000 lb_f).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（应力、模量等）来求解最大载荷，答案也是具体的数值结果。 | 知识层次: 题目涉及基本的应力计算和公式应用，只需要直接套用应力公式（应力=力/面积）来计算最大载荷，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（应力=力/面积）进行计算，无需组合多个公式或进行复杂的概念分析。题目提供了所有必要的数据，解题步骤简单直接，属于最基础的难度等级。", "convertible": true, "correct_option": "44,850 N (10,000 lb_f)", "choice_question": "For a brass alloy, the stress at which plastic deformation begins is 345 MPa (50,000 psi), and the modulus of elasticity is 103 GPa (15.0 x 10^6 psi). What is the maximum load that can be applied to a specimen with a cross-sectional area of 130 mm^2 (0.2 in.^2) without plastic deformation?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "44,850 N (10,000 lb_f)", "B": "13,395 N (3,000 lb_f)", "C": "89,700 N (20,000 lb_f)", "D": "53,820 N (12,000 lb_f)" }, "correct_answer": "A", "explanation": "正确答案A是通过将屈服应力(345 MPa)乘以横截面积(130 mm^2)计算得出的。干扰项B利用了弹性模量(103 GPa)的1/10作为应力阈值，这是典型的单位混淆陷阱。干扰项C是屈服应力的两倍，利用了材料科学中常见的'安全系数'直觉错误。干扰项D故意使用了与弹性模量数值相近但单位错误的计算(103 x 130 x 4)，这是基于材料参数间关系的常见误解设计的。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3181, "question": "Given that the unit dislocation a/2 [101] can combine with the Shockley partial dislocation [121] to form a Frank partial dislocation, determine the Burgers vector of the newly formed Frank partial dislocation.", "answer": "The Burgers vector of the newly formed Frank partial dislocation is b, where b = a/2 [101] + a/6 [121] = a/3 [111].", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过矢量加法计算新形成的Frank位错的Burgers矢量，涉及数值计算和公式应用。答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算（Burgers向量的叠加运算），并需要理解位错组合的概念和Frank部分位错的形成机制。虽然不涉及复杂的综合分析或创新应用，但需要将不同概念关联起来进行中等难度的计算。 | 难度: 在选择题中属于中等偏上难度，需要理解位错的基本概念（如单位位错、Shockley部分位错、Frank部分位错），掌握Burgers矢量的叠加原理，并进行多步矢量计算。虽然题目提供了正确选项，但解题过程涉及多个概念的关联和综合计算，对学生的知识掌握深度和计算能力有一定要求。", "convertible": true, "correct_option": "a/3 [111]", "choice_question": "Given that the unit dislocation a/2 [101] can combine with the Shockley partial dislocation [121] to form a Frank partial dislocation, what is the Burgers vector of the newly formed Frank partial dislocation?", "conversion_reason": "The answer is a specific and well-defined vector, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "a/3 [111]", "B": "a/2 [111]", "C": "a/6 [121]", "D": "a/3 [101]" }, "correct_answer": "A", "explanation": "The correct Burgers vector is a/3 [111] because the vector addition of a/2 [101] and a/6 [121] results in a/3 [111]. Option B is a common intuitive error due to the presence of a/2 in the original dislocation. Option C is the original Shockley partial dislocation, tempting those who forget the combination process. Option D mimics the unit dislocation direction but with incorrect magnitude, exploiting directional similarity bias.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4673, "question": "To what equation does the expression for interplanar spacing (d_{\text {hkl }}) reduce for crystals having cubic symmetry, given that (a,(b), and c are the lattice parameters?", "answer": "For the crystals having cubic symmetry, a=b=c. Making this substitution into the given equation leads to (\frac{1}{d_{h k l}^{2}}=\frac{h^{2}}{a^{2}}+\frac{k^{2}}{a^{2}}+\frac{l^{2}}{a^{2}} = \frac{h^{2}+k^{2}+l^{2}}{a^{2}}).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释立方对称晶体的晶面间距表达式如何简化，答案提供了详细的推导过程和文字解释，符合简答题的特征。 | 知识层次: 题目要求将立方对称晶体的条件（a=b=c）代入晶面间距公式进行简化，属于基本公式的直接应用，无需多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单应用难度。题目要求考生将立方晶系的对称性条件（a=b=c）直接代入晶面间距公式，并进行简单的代数运算。解题步骤明确且直接，无需复杂的推导或分析。考生只需掌握基本公式和简单计算能力即可正确作答，符合选择题型中等级2的简单应用要求。", "convertible": true, "correct_option": "For the crystals having cubic symmetry, a=b=c. Making this substitution into the given equation leads to (rac{1}{d_{h k l}^{2}}=rac{h^{2}}{a^{2}}+rac{k^{2}}{a^{2}}+rac{l^{2}}{a^{2}} = rac{h^{2}+k^{2}+l^{2}}{a^{2}}).", "choice_question": "To what equation does the expression for interplanar spacing (d_{ ext {hkl }}) reduce for crystals having cubic symmetry, given that (a,(b), and c are the lattice parameters?", "conversion_reason": "The answer is a standard equation that can be presented as a correct option among other plausible but incorrect equations.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1/d² = (h² + k² + l²)/a²", "B": "d = a/√(h² + k² + l²)", "C": "1/d = (h + k + l)/a", "D": "d = a/(h + k + l)" }, "correct_answer": "A", "explanation": "The correct answer A is derived from the general interplanar spacing formula by substituting a=b=c for cubic symmetry. Option B is dimensionally correct but reverses the relationship, exploiting visual similarity to the correct form. Option C uses a linear sum of indices instead of quadratic sum, targeting common algebraic errors. Option D combines the errors of B and C, creating a particularly deceptive trap for those relying on pattern recognition rather than rigorous derivation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 979, "question": "What is the difference in phase transformation resistance between the solid-state phase transformation of metals and the crystallization process of metals?", "answer": "There is an additional term of strain energy in the phase transformation resistance.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释金属的固态相变和结晶过程在相变阻力上的差异，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求比较金属固态相变和结晶过程的相变阻力差异，并解释其中应变能的作用。这需要深入理解相变机制、能量变化和微观结构演变，涉及多个概念的关联和综合分析，属于较高层次的认知能力要求。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "There is an additional term of strain energy in the phase transformation resistance.", "choice_question": "What is the difference in phase transformation resistance between the solid-state phase transformation of metals and the crystallization process of metals?", "conversion_reason": "The answer is a standard concept or term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The presence of dislocation density affects only solid-state transformations", "B": "Crystallization requires overcoming surface energy while solid-state transformations do not", "C": "Both processes have identical activation energies when normalized by volume", "D": "Solid-state transformations involve additional grain boundary diffusion resistance" }, "correct_answer": "A", "explanation": "The correct answer is A because solid-state phase transformations involve strain energy from dislocation interactions, which is absent in crystallization from liquid. Option B is incorrect because both processes involve surface energy considerations. Option C is a cognitive bias trap - while activation energies may appear similar, their components differ fundamentally. Option D exploits professional intuition by incorrectly attributing grain boundary effects to the transformation resistance itself rather than kinetics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2192, "question": "Why is the actual tensile strength of ceramics lower than the theoretical yield strength?", "answer": "This is due to the unavoidable microscopic voids present during the sintering of ceramic powders. During cooling or thermal cycling, thermal stresses generate microcracks, and surface cracks caused by corrosion result in ceramics, unlike metals, having inherent microcracks. At the crack tip, severe stress concentration occurs. According to elastic mechanics estimates, the maximum stress at the crack tip has already reached the theoretical fracture strength or theoretical yield strength (because ceramic crystals have very few mobile dislocations, and dislocation motion is extremely difficult, so once the yield strength is reached, fracture occurs). Conversely, one can calculate the nominal stress at which the crystal fractures when the maximum stress at the crack tip equals the theoretical yield strength, and this value is extremely close to the actual measured tensile strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么陶瓷的实际拉伸强度低于理论屈服强度，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目需要综合运用弹性力学、陶瓷材料微观结构和断裂机理等多方面知识进行深入分析和解释，涉及复杂的应力集中和理论强度与实际强度差异的机理探讨。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解陶瓷材料的基本性能，还需要深入掌握微观结构缺陷（如微孔、微裂纹）对材料强度的影响机制。正确选项涉及复杂的应力集中分析、理论强度与实际强度的差异解释，以及陶瓷晶体中位错运动的特殊性。此外，解题过程需要综合运用弹性力学和材料科学知识进行推理分析，属于复杂现象的全面分析层次，远超一般选择题的概念记忆或简单应用要求。", "convertible": true, "correct_option": "This is due to the unavoidable microscopic voids present during the sintering of ceramic powders. During cooling or thermal cycling, thermal stresses generate microcracks, and surface cracks caused by corrosion result in ceramics, unlike metals, having inherent microcracks. At the crack tip, severe stress concentration occurs. According to elastic mechanics estimates, the maximum stress at the crack tip has already reached the theoretical fracture strength or theoretical yield strength (because ceramic crystals have very few mobile dislocations, and dislocation motion is extremely difficult, so once the yield strength is reached, fracture occurs). Conversely, one can calculate the nominal stress at which the crystal fractures when the maximum stress at the crack tip equals the theoretical yield strength, and this value is extremely close to the actual measured tensile strength.", "choice_question": "Why is the actual tensile strength of ceramics lower than the theoretical yield strength?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Due to stress concentration at inherent microcracks exceeding theoretical strength", "B": "Because ceramic powders have lower packing density than metal powders", "C": "Owing to the absence of dislocation movement in ceramic crystal structures", "D": "Due to the higher elastic modulus of ceramics compared to metals" }, "correct_answer": "A", "explanation": "Correct answer A addresses the key mechanism of stress concentration at microcracks. Distractors: B exploits the common but irrelevant observation about powder packing density; C uses a partially correct fact (dislocation difficulty) but presents it as the primary cause; D leverages the true but unrelated property of elastic modulus to create a plausible-sounding distraction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 469, "question": "Pseudoeutectoid transformation", "answer": "Pseudoeutectoid transformation: During non-equilibrium transformation, hypoeutectoid or hypereutectoid alloys near the eutectoid composition point exhibit a fully eutectoid microstructure upon completion of the transformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对\"Pseudoeutectoid transformation\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查对非平衡转变过程中伪共析转变现象的解释，需要综合运用相变原理、非平衡条件影响等知识进行机理分析，涉及较深层次的概念关联和推理分析能力。 | 难度: 在选择题型中，该题目属于最高难度等级。题目涉及非平衡转变条件下的伪共析转变现象，要求考生不仅掌握共析转变的基本概念，还需要理解亚共析/过共析合金在特定条件下的微观结构变化机理。这种题目需要考生具备：1) 深入的热力学和动力学知识；2) 对非平衡转变过程的理解；3) 综合分析合金成分与微观结构关系的能力。在选择题型中，这种需要多维度知识整合和机理分析的题目属于最复杂的类型。", "convertible": true, "correct_option": "Pseudoeutectoid transformation: During non-equilibrium transformation, hypoeutectoid or hypereutectoid alloys near the eutectoid composition point exhibit a fully eutectoid microstructure upon completion of the transformation.", "choice_question": "下列关于Pseudoeutectoid transformation的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pseudoeutectoid transformation occurs when hypoeutectoid or hypereutectoid alloys near the eutectoid composition exhibit fully eutectoid microstructure under non-equilibrium conditions", "B": "Pseudoeutectoid transformation is a special case of martensitic transformation where the parent phase transforms into a mixture of ferrite and cementite", "C": "Pseudoeutectoid transformation describes the formation of pearlite in hypereutectoid steels during extremely slow cooling rates", "D": "Pseudoeutectoid transformation refers to the abnormal growth of proeutectoid phase that mimics eutectoid morphology at high undercooling" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines pseudoeutectoid transformation as a non-equilibrium phenomenon where near-eutectoid alloys develop fully eutectoid microstructure. Option B incorrectly associates it with martensitic transformation. Option C confuses it with normal pearlite formation kinetics. Option D describes a proeutectoid growth anomaly rather than the pseudoeutectoid phenomenon. Advanced AIs might be misled by the martensitic transformation reference (B) or the slow cooling condition (C), both being plausible-sounding but incorrect associations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2112, "question": "Point out the errors in the following concept and correct them: From the condition for constitutional supercooling < concentration _{\text {holes }}", "choice_question": "For an n-type semiconductor:", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provided clearly indicates the correct option, which is not explicitly listed but can be inferred as 'Concentration _{\text {electrons }}> concentration _{\text {holes }}'. The question can be converted to a single-choice format by including this correct option among the choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The electron mobility in n-type GaAs decreases with increasing temperature above room temperature", "B": "The electron mobility in n-type GaAs is primarily limited by ionized impurity scattering at 300K", "C": "The electron mobility in n-type GaAs shows a T^3/2 temperature dependence due to acoustic phonon scattering", "D": "The electron mobility in n-type GaAs is higher than its hole mobility due to smaller effective mass" }, "correct_answer": "A", "explanation": "Correct answer A: In GaAs, above room temperature, polar optical phonon scattering becomes dominant, causing mobility to decrease with temperature. This requires deep understanding of compound semiconductor physics. Distractors: B exploits confusion between Si and GaAs (ionized impurity scattering dominates in Si at low T). C uses incorrect exponent (acoustic phonon scattering gives T^-3/2). D seems plausible but the mobility difference is actually due to valley anisotropy, not just effective mass.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1006, "question": "If a piece of iron is heated from room temperature 20°C to 850°C, then cooled very quickly to 20°C, calculate the change in the number of vacancies before and after the treatment (assuming the energy required to form 1 mole of vacancies in iron is 104600J).", "answer": "$$ \\\\cdot\\\\frac{c_{850\\\\mathrm{PC}}}{c_{20\\\\mathrm{PC}}}=\\\\frac{A\\\\mathrm{e}^{-\\\\frac{\\\\Delta E}{k\\\\cdot(850+273)}}}{A\\\\mathrm{e}^{-\\\\frac{\\\\Delta E}{k\\\\cdot(20+273)}}}=\\\\mathrm{e}^{-\\\\frac{104675}{1123\\\\times8.31}\\\\frac{104675}{293\\\\times8.31}}=6.3\\\\times10^{13}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算，应用给定的公式和参数来计算空位数的变化，答案是一个具体的计算结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括温度转换（摄氏到开尔文）、应用阿伦尼乌斯公式计算空位浓度比，以及对数运算。虽然不涉及多个概念的复杂关联或深度机理分析，但需要正确理解和应用热力学公式进行计算，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要理解空位形成能的概念，掌握阿伦尼乌斯公式的应用，并进行多步温度单位转换和指数计算。虽然题目提供了关键参数，但需要综合运用热力学和材料科学知识完成从摄氏温度到开尔文温度的转换、玻尔兹曼常数应用以及复杂的指数运算。相比简单记忆或单步计算的选择题，该题目对计算能力和概念关联性要求较高，但尚未达到多变量交互作用的复杂程度。", "convertible": true, "correct_option": "6.3×10^13", "choice_question": "If a piece of iron is heated from room temperature 20°C to 850°C, then cooled very quickly to 20°C, what is the change in the number of vacancies before and after the treatment (assuming the energy required to form 1 mole of vacancies in iron is 104600J)?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.3×10^13", "B": "1.2×10^14", "C": "3.8×10^12", "D": "The number of vacancies remains unchanged" }, "correct_answer": "A", "explanation": "The correct answer is A because the number of vacancies is determined by the equilibrium at the highest temperature (850°C) and is 'frozen in' during rapid cooling. Option B is a cognitive bias trap, doubling the correct value to exploit quick mental calculations. Option C uses a plausible-looking exponent but wrong coefficient, targeting unit confusion. Option D is a professional intuition trap, appealing to the misconception that vacancies would annihilate during cooling.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4000, "question": "How would the plane strain fracture toughness of a metal be expected to change with rising temperature?(a) Increase(b) Decrease(c) Remain constant", "answer": "The magnitude of the plane strain fracture toughness, K_{i c}, diminishes with decreasing temperature; therefore as temperature increases, K_{i c}, should also increase.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求从给定的选项(a)、(b)、(c)中选择正确答案，符合选择题的特征 | 知识层次: 题目需要理解平面应变断裂韧性与温度变化的关系，并应用相关知识进行推理分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解金属的平面应变断裂韧性（K_{ic}）与温度变化的关系这一概念，并能够综合分析温度升高对材料性能的影响。虽然题目涉及的知识点较为专业，但选项明确，不需要复杂的计算过程，属于多概念综合选择的范畴。", "convertible": true, "correct_option": "Increase", "choice_question": "How would the plane strain fracture toughness of a metal be expected to change with rising temperature?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option. The answer provided confirms that the correct choice is (a) Increase.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increase due to enhanced dislocation mobility reducing crack tip stress concentration", "B": "Decrease due to thermal softening reducing material's resistance to crack propagation", "C": "Remain constant as it's an intrinsic material property independent of temperature", "D": "First decrease then increase due to competing mechanisms of thermal activation and creep relaxation" }, "correct_answer": "A", "explanation": "The correct answer is A because plane strain fracture toughness (K_IC) generally increases with temperature due to enhanced plasticity at the crack tip from greater dislocation mobility. Option B exploits the common misconception that thermal softening always reduces mechanical properties. Option C traps those who confuse fracture toughness with fundamental material constants. Option D is a multi-mechanism trap that appears sophisticated but misrepresents the typical monotonic relationship for metals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 329, "question": "Under the same degree of supercooling, compare the critical radius, critical nucleation work, and critical nucleus volume between homogeneous nucleation and heterogeneous nucleation. Which is larger?", "answer": "The critical radius is the same; the critical nucleation work is higher for homogeneous nucleation; the critical nucleus volume is also larger for homogeneous nucleation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求比较均相成核和非均相成核的临界半径、临界成核功和临界核体积，并说明哪个更大。答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求比较均相成核和非均相成核的临界半径、临界成核功和临界核体积，需要理解成核理论的基本概念，并能够应用这些概念进行综合分析。虽然不涉及复杂的计算，但需要对不同成核方式的特点有较深的理解，并进行对比分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，题目要求比较均匀成核和非均匀成核在相同过冷度下的临界半径、临界成核功和临界核体积，并判断哪个更大。这需要深入理解成核理论，能够综合分析多个参数之间的关系，并进行多步比较和判断。虽然题目提供了正确选项，但解题过程涉及多个概念的关联和综合分析，属于多角度分析论述的难度等级。", "convertible": true, "correct_option": "The critical radius is the same; the critical nucleation work is higher for homogeneous nucleation; the critical nucleus volume is also larger for homogeneous nucleation.", "choice_question": "Under the same degree of supercooling, compare the critical radius, critical nucleation work, and critical nucleus volume between homogeneous nucleation and heterogeneous nucleation. Which of the following is correct?", "conversion_reason": "The answer is a standard comparison between homogeneous and heterogeneous nucleation, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical radius is the same; the critical nucleation work is higher for homogeneous nucleation; the critical nucleus volume is also larger for homogeneous nucleation", "B": "The critical radius is smaller for heterogeneous nucleation; the critical nucleation work is the same; the critical nucleus volume is smaller for homogeneous nucleation", "C": "The critical radius is larger for homogeneous nucleation; the critical nucleation work is higher for heterogeneous nucleation; the critical nucleus volume is the same", "D": "All three parameters (critical radius, nucleation work, and nucleus volume) are smaller for heterogeneous nucleation" }, "correct_answer": "A", "explanation": "The critical radius depends only on thermodynamic conditions (same for both nucleation types under identical supercooling). Heterogeneous nucleation requires less work due to reduced surface energy at the substrate interface. The critical nucleus volume is larger for homogeneous nucleation because it must overcome higher energy barriers without substrate assistance. Option B incorrectly assumes radius differs and confuses work relationships. Option C reverses the work relationship and incorrectly states radius differs. Option D is overly simplistic and ignores the identical critical radius condition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1752, "question": "There are types of spatial lattice forms that may correspond to the seven crystal systems.", "answer": "14", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个具体的数字答案（14），这属于需要直接回答的简答题形式，而不是从选项中选择或判断对错 | 知识层次: 题目考查对晶体系统与空间格子类型对应关系的基础概念记忆，属于分类和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需回忆晶体系统对应的空间格子类型数量这一简单事实。题目不涉及复杂概念体系或解题步骤，仅需直接选择正确数字选项，因此属于最低难度等级。", "convertible": true, "correct_option": "14", "choice_question": "How many types of spatial lattice forms may correspond to the seven crystal systems?", "conversion_reason": "The answer is a specific number, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "14 (Bravais lattices)", "B": "7 (corresponding to crystal systems)", "C": "32 (crystallographic point groups)", "D": "230 (space groups)" }, "correct_answer": "A", "explanation": "The correct answer is A because there are exactly 14 Bravais lattices that describe all possible spatial arrangements of points in crystal structures, corresponding to the 7 crystal systems. Option B is a common first-impression error where one might assume the number directly matches the crystal systems. Option C exploits confusion with the 32 crystallographic point groups, while D uses the much larger number of space groups which is a more advanced concept. These options target different levels of crystallography knowledge to create cognitive traps.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3009, "question": "Silicate glass, mica, and asbestos belong to which category of compounds? Options: A. Carbon-chain organic polymers B. Heterochain organic polymers C. Elemental organic compounds D. Inorganic polymers", "answer": "D", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的四个选项中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查对无机聚合物分类的基本概念记忆，只需识别给定的材料属于哪一类化合物，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，此题属于基础概念记忆类型，仅需识别无机聚合物的常见实例（硅酸盐玻璃、云母、石棉）。选项区分明显，无需复杂分析或概念辨析，符合等级1\"简单概念识别，直接记忆\"的标准。", "convertible": true, "correct_option": "D. Inorganic polymers", "choice_question": "Silicate glass, mica, and asbestos belong to which category of compounds?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Carbon-chain organic polymers", "B": "Heterochain organic polymers", "C": "Elemental organic compounds", "D": "Inorganic polymers" }, "correct_answer": "D", "explanation": "The correct answer is D because silicate glass, mica, and asbestos are all examples of inorganic polymers, which are large molecules composed of repeating structural units but without a carbon backbone. Option A is designed to exploit the common association of 'polymer' with organic chemistry. Option B targets confusion between silicon-based and heteroatom-containing organic polymers. Option C creates a trap by suggesting these are simple elemental compounds rather than polymeric structures. Advanced AI models might be misled by the strong semantic association between 'polymer' and organic chemistry, or by overgeneralizing from common polymer examples.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1206, "question": "The characteristics of polycrystalline plastic deformation are (18)ity, (19)ity, and (20)ity.", "answer": "(18) non-simultaneous; (19) coordinated; (20) non-uniform", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写特定的单词或短语来完成句子，而不是从给定的选项中选择或进行判断。答案需要根据知识储备来填写，属于简答题的范畴。 | 知识层次: 题目考查对多晶塑性变形特性的基础概念记忆，仅需回忆并填写三个特征词汇，无需深入分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆，但需要考生准确回忆并匹配三个不同的特性（非同时性、协调性和非均匀性），这比单纯记忆一个定义或概念要复杂一些。此外，题目采用了填空题的形式，增加了对记忆准确性的要求。不过，由于选项已经给出，考生不需要进行复杂的推理或分析，因此难度仍属于中等水平。", "convertible": true, "correct_option": "non-simultaneous, coordinated, non-uniform", "choice_question": "The characteristics of polycrystalline plastic deformation are:", "conversion_reason": "The answer consists of standard terms that can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "non-simultaneous, coordinated, non-uniform", "B": "simultaneous, uncoordinated, uniform", "C": "non-simultaneous, uncoordinated, uniform", "D": "simultaneous, coordinated, non-uniform" }, "correct_answer": "A", "explanation": "The correct answer is A because polycrystalline plastic deformation occurs in a non-simultaneous manner (grains deform at different times), requires coordination between grains to maintain continuity, and is inherently non-uniform due to grain orientation differences. Option B is wrong but tempting as it mirrors single crystal deformation characteristics. Option C exploits the common misconception that non-simultaneity implies uncoordinated deformation. Option D combines correct 'coordinated' and 'non-uniform' with incorrect 'simultaneous' to create a plausible-sounding but wrong combination.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3988, "question": "Tensile strengths and number-average molecular weights for two polymers are as follows:\nTensile strength Number average molecular weight\n(MPa)\n(\\mathrm{g} / mol)\n37.7\n36800\n131\n62400\nEstimate the tensile strength (in MPa) for a number-average molecular weight of 51500g / mol.", "answer": "the tensile strength for a number-average molecular weight of 51500g/mol is 95.2 MPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目提供了两组拉伸强度和数均分子量的数据，要求根据这些数据估算另一个分子量下的拉伸强度。这需要通过数值计算和可能的插值或外推方法来完成。答案是一个具体的数值计算结果，符合计算题的特征。 | 知识层次: 题目要求根据给定的数据点进行简单的线性插值计算，属于基本公式的直接应用，无需多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单应用层次，需要基本公式应用和简单计算。虽然涉及线性插值，但步骤明确且直接，属于简单公式应用计算。", "convertible": true, "correct_option": "95.2 MPa", "choice_question": "Given the tensile strengths and number-average molecular weights for two polymers as follows: Tensile strength (MPa) 37.7 and 131, Number average molecular weight (g/mol) 36800 and 62400. Estimate the tensile strength (in MPa) for a number-average molecular weight of 51500 g/mol.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "95.2 MPa", "B": "112.4 MPa", "C": "84.3 MPa", "D": "68.7 MPa" }, "correct_answer": "A", "explanation": "正确答案A是通过线性插值计算得出的精确值。干扰项B利用了对数关系的直觉陷阱，看似更符合聚合物强度随分子量变化的典型非线性趋势。干扰项C故意使用了错误的斜率计算，而干扰项D则利用了低分子量区域可能出现的强度平台效应这一认知偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2319, "question": "In a Kevlar fiber-epoxy resin composite, the fiber volume fraction is 0.3, the density of epoxy resin is 1.25 g/cm³, and the density of Kevlar fiber is 1.44 g/cm³. Calculate the density of this composite material.", "answer": "The density is ρ=1.31 g/cm³. Calculation process: ρ_L=1.25×0.7+1.44×0.3=1.3078 g/cm³.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算复合材料的密度），并给出了具体的计算过程和公式应用（ρ_L=1.25×0.7+1.44×0.3=1.3078 g/cm³）。答案也是一个具体的数值结果（1.31 g/cm³），符合计算题的特征。 | 知识层次: 题目涉及基本公式应用和简单计算，仅需直接套用复合材料密度计算公式，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目仅要求应用简单的混合密度公式（ρ_L=ρ_1×V_1+ρ_2×V_2）进行计算，无需额外的概念理解或复杂步骤。学生只需正确代入给定的数值（纤维体积分数、树脂密度和纤维密度）即可得出答案。这种类型的题目在选择题中属于最基础的难度级别。", "convertible": true, "correct_option": "1.31 g/cm³", "choice_question": "In a Kevlar fiber-epoxy resin composite, the fiber volume fraction is 0.3, the density of epoxy resin is 1.25 g/cm³, and the density of Kevlar fiber is 1.44 g/cm³. What is the density of this composite material?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.31 g/cm³", "B": "1.38 g/cm³", "C": "1.27 g/cm³", "D": "1.44 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the rule of mixtures for composite density: ρ_composite = V_fiber * ρ_fiber + V_matrix * ρ_matrix = 0.3*1.44 + 0.7*1.25 = 1.31 g/cm³. Option B is designed to exploit the cognitive bias of averaging densities (1.44+1.25)/2=1.345≈1.38. Option C reverses the volume fractions (0.7*1.44 + 0.3*1.25). Option D is the pure fiber density, testing if the model ignores the matrix contribution.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4412, "question": "Cite three sources of internal residual stresses in metal components.", "answer": "Three sources of residual stresses in metal components are plastic deformation processes, nonuniform cooling of a piece that was cooled from an elevated temperature, and a phase transformation in which parent and product phases have different densities.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举金属构件中内部残余应力的三个来源，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对金属构件内部残余应力来源的基本概念记忆和理解，属于基础概念记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生列举金属构件内部残余应力的三个来源，属于概念解释和描述层次。虽然需要记忆多个知识点，但每个来源都是相对独立的基础概念，不需要进行复杂的比较分析或深入的概念体系阐述。相比等级1的基本定义简答，该题目对知识点的掌握深度要求略高，但仍属于中等难度范围。", "convertible": true, "correct_option": "plastic deformation processes, nonuniform cooling of a piece that was cooled from an elevated temperature, and a phase transformation in which parent and product phases have different densities", "choice_question": "Which of the following are sources of internal residual stresses in metal components?", "conversion_reason": "The answer is a standard list of causes for residual stresses, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Plastic deformation processes", "B": "Uniform cooling from elevated temperature", "C": "Elastic deformation below yield point", "D": "Isotropic thermal expansion" }, "correct_answer": "A", "explanation": "Plastic deformation processes create residual stresses due to non-uniform material flow. Uniform cooling (B) is incorrect because residual stresses require non-uniform cooling. Elastic deformation (C) does not create residual stresses as strains are fully recoverable. Isotropic thermal expansion (D) cannot create residual stresses as it occurs uniformly in all directions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 395, "question": "Grain boundaries with a misorientation angle less than $2^{\\circ}$ between adjacent grains are called high-angle grain boundaries.", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（Grain boundaries with a misorientation angle less than $2^{\\circ}$ between adjacent grains are called high-angle grain boundaries），并要求判断其正误（答案给出的是×表示错误），这符合判断题的特征。 | 知识层次: 题目考查对晶界分类的基本概念记忆，特别是低角度晶界和高角度晶界的定义区分，属于基础概念记忆性知识。 | 难度: 该题目属于基础概念记忆层次，仅需判断关于晶界分类的定义是否正确。题目陈述明确，只需识别\"小于2°的晶界称为小角度晶界\"这一基本概念即可判断正误，无需深入理解或分析。在选择题型中，这类直接考察定义记忆的题目属于最简单的难度等级。", "convertible": true, "correct_option": "×", "choice_question": "Grain boundaries with a misorientation angle less than $2^{\\circ}$ between adjacent grains are called high-angle grain boundaries.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials will crystallize when heated above their glass transition temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many amorphous materials can crystallize above their glass transition temperature, this is not universally true. Some materials (like certain polymer blends or network glasses) may remain amorphous due to kinetic barriers or thermodynamic stability. The statement's use of 'all' creates an absolute claim that doesn't account for exceptions in material behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3847, "question": "For an Fe-0.35% C alloy, determine the primary microconstituent that forms.", "answer": "primary α-ferrite", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求确定合金的主要微观组成，需要基于材料科学知识进行文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目要求根据给定的合金成分（Fe-0.35% C）确定主要微观组成物（primary α-ferrite），这需要应用铁碳相图的基本知识，属于直接套用相图信息的简单应用。虽然需要理解相图的基本概念，但不需要多步计算或综合分析，思维过程较为直接。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需根据给定的Fe-0.35% C合金成分直接套用铁碳相图的基本知识即可确定主要微观组织为primary α-ferrite。解题步骤简单直接，无需复杂计算或多概念综合分析，因此在选择题型内属于较低难度等级。", "convertible": true, "correct_option": "primary α-ferrite", "choice_question": "For an Fe-0.35% C alloy, which of the following is the primary microconstituent that forms?", "conversion_reason": "The answer is a standard term in materials science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "primary α-ferrite", "B": "proeutectoid cementite", "C": "pearlite", "D": "ledeburite" }, "correct_answer": "A", "explanation": "The correct answer is primary α-ferrite because for an Fe-0.35% C alloy (hypoeutectoid composition), the first phase to form upon cooling from the austenite phase field is α-ferrite. Option B (proeutectoid cementite) is a cognitive bias trap - it appears plausible for carbon steels but only forms in hypereutectoid alloys (>0.76% C). Option C (pearlite) exploits the AI's tendency to recall the most common microstructure in steels, but pearlite forms at the eutectoid reaction, not as the primary constituent. Option D (ledeburite) is a professional intuition trap - while important in cast irons, it doesn't form in this low-carbon steel composition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3854, "question": "For an Fe-1.15% C alloy, determine the composition and amount of each phase present at 720 degrees C.", "answer": "alpha: 0.0218% C, 83%; Fe3C: 6.67% C, 17%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算确定合金中各相的组成和含量，需要使用相图和杠杆定律进行数值计算，答案给出了具体的数值结果。 | 知识层次: 题目需要应用铁碳相图进行多步计算，包括确定相组成和相对含量，涉及概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图的基本概念，能够正确读取特定温度下的相组成，并应用杠杆定律进行多步骤计算。虽然题目提供了正确选项，但解题过程涉及多个知识点的综合应用和计算步骤，对学生的理解能力和计算能力有一定要求。", "convertible": true, "correct_option": "alpha: 0.0218% C, 83%; Fe3C: 6.67% C, 17%", "choice_question": "For an Fe-1.15% C alloy, what is the composition and amount of each phase present at 720 degrees C?", "conversion_reason": "The answer is a specific and deterministic result, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "alpha: 0.0218% C, 83%; Fe3C: 6.67% C, 17%", "B": "alpha: 0.0218% C, 87%; Fe3C: 6.67% C, 13%", "C": "gamma: 0.77% C, 83%; Fe3C: 6.67% C, 17%", "D": "alpha: 0.77% C, 83%; Fe3C: 6.67% C, 17%" }, "correct_answer": "A", "explanation": "The correct answer uses the lever rule calculation at 720°C where the alloy is in the alpha + Fe3C phase field. Option B is a common calculation error where the phase fractions are inverted. Option C exploits the cognitive bias of expecting gamma phase at high temperatures, though it's actually below the eutectoid temperature. Option D uses the correct phase fractions but incorrectly assigns the eutectoid composition to the alpha phase.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4194, "question": "What electron subshell is being filled for the rare earth series of elements on the periodic table?", "answer": "The 4 f subshell is being filled for the rare earth series of elements.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释哪个电子亚层正在被填充，答案需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查对元素周期表中稀土元素电子填充亚层的基本概念记忆，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅要求记忆并识别稀土元素填充的电子亚层（4f），无需解释或分析复杂概念。这是对基础概念的直接回忆，符合选择题型中最简单的难度等级标准。", "convertible": true, "correct_option": "The 4 f subshell is being filled for the rare earth series of elements.", "choice_question": "Which electron subshell is being filled for the rare earth series of elements on the periodic table?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4f", "B": "5d", "C": "6s", "D": "4d" }, "correct_answer": "A", "explanation": "The correct answer is A (4f) because the rare earth series (lanthanides) involves the filling of the 4f subshell. Option B (5d) is a trap for those who confuse lanthanides with transition metals where d orbitals are filled. Option C (6s) exploits the common knowledge that s orbitals fill first, but ignores the specific context of lanthanides. Option D (4d) is designed to trigger confusion between lanthanides and the second transition series.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 444, "question": "Generally speaking, during solid-state phase transformations, crystal defects in the parent phase can promote the formation of the new phase.", "answer": "(√)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对固态相变中晶体缺陷作用的基本概念记忆和理解，属于基础知识的直接应用。 | 难度: 该题目属于基础概念正误判断，仅需记忆晶体缺陷对固态相变的影响这一基本原理即可作答。在选择题型中属于最简单的难度等级，不需要复杂的分析或推理过程。", "convertible": true, "correct_option": "(√)", "choice_question": "Generally speaking, during solid-state phase transformations, crystal defects in the parent phase can promote the formation of the new phase.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All types of crystal defects in the parent phase will always accelerate the nucleation rate during solid-state phase transformations.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many crystal defects (like dislocations and grain boundaries) generally promote nucleation by providing lower-energy sites, some special defects (like coherent twin boundaries) may actually inhibit phase transformation. The use of 'all' and 'always' makes this statement incorrect. Additionally, the effect depends on defect type, energy, and interaction with the new phase.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3041, "question": "What are the main components of YT30 alloy?", "answer": "WC, TiC, and Co", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举YT30合金的主要成分，答案以文字形式给出具体成分，不需要计算或选择，属于简答题类型 | 知识层次: 题目考查对YT30合金主要成分的基础概念记忆，属于定义和分类层面的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目直接询问YT30合金的主要成分，正确选项明确列出了三种成分（WC, TiC, Co），属于基础概念记忆层次。学生只需回忆合金的基本组成即可作答，无需进行概念解释或复杂分析，符合等级1的简单记忆性知识要求。", "convertible": true, "correct_option": "WC, TiC, and Co", "choice_question": "What are the main components of YT30 alloy?", "conversion_reason": "The answer is a standard set of terms that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "WC, TiC, and Co", "B": "WC, TiN, and Ni", "C": "TiC, TaC, and Co", "D": "WC, TiC, and Ni" }, "correct_answer": "A", "explanation": "The correct answer is A because YT30 is a cemented carbide alloy primarily composed of tungsten carbide (WC), titanium carbide (TiC), and cobalt (Co) as the binder. Option B replaces TiC with TiN and Co with Ni, which are common substitutions in other alloys but not in YT30. Option C replaces WC with TaC, a less common but plausible substitution that could mislead based on general knowledge of carbide alloys. Option D replaces Co with Ni, exploiting the common confusion between these binder metals in cemented carbides. All incorrect options leverage real material combinations to create plausible but contextually wrong answers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3915, "question": "Which crystal system(s) listed below has (have) the following relationship for the unit cell edge lengths?\n\\[\na=b \\neq c\n\\](a) Cubic(b) Hexagonal(c) Tetragonal\n\\mathrm{d}) Rhombohedral(e) Orthorhombic(f) Monoclinic (g) Triclinic", "answer": "For both hexagonal and tetragonal crystal systems two of the unit cell edge lengths are equal to one another, but unequal to the third length.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择符合特定条件的晶体系统，答案明确给出了符合条件的选项，符合选择题的特征。 | 知识层次: 题目考查对晶体系统基本特征和分类的记忆和理解，不需要复杂的计算或分析。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要记忆不同晶系的晶胞边长关系，但题目明确给出了关键特征（a=b≠c），并提供了选项供选择。考生只需识别并匹配Hexagonal和Tetragonal两种晶系的特征即可，不需要进行复杂的分析或推导。这属于基础概念记忆和简单辨析的范畴。", "convertible": true, "correct_option": "For both hexagonal and tetragonal crystal systems two of the unit cell edge lengths are equal to one another, but unequal to the third length.", "choice_question": "Which crystal system(s) listed below has (have) the following relationship for the unit cell edge lengths?\n\na=b ≠ c", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provided is a clear explanation that can be matched to the options given. Therefore, it can be converted to a single-choice question format by selecting the correct option based on the provided answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Tetragonal only", "B": "Hexagonal only", "C": "Both tetragonal and hexagonal", "D": "Tetragonal and rhombohedral" }, "correct_answer": "C", "explanation": "The correct answer is C because both tetragonal and hexagonal crystal systems satisfy the condition a=b≠c. Option A is a cognitive bias trap, exploiting the immediate association of tetragonal with this condition while ignoring hexagonal. Option B is a professional intuition trap, capitalizing on the common oversight that hexagonal systems also have two equal edge lengths. Option D is a multi-level verification trap, introducing rhombohedral which has a=b=c, requiring simultaneous consideration of multiple crystal systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2523, "question": "Explain the term: solid solution", "answer": "The atoms of the solute and the solvent occupy a common Bravais lattice, and this lattice type is the same as that of the solvent; the content of the components can vary within a certain range without causing a change in the lattice type. Metal or non-metal compounds possessing these two properties are called solid solutions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释术语\"solid solution\"，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对“solid solution”这一基本概念的定义和特性的记忆和理解，不涉及应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释\"solid solution\"这一概念，但正确选项提供了较为详细的定义和关键特征描述，包括溶质和溶剂原子占据共同的Bravais晶格、晶格类型与溶剂相同、组分含量可在一定范围内变化等。这超出了简单定义记忆（等级1），但尚未达到需要阐述复杂概念体系（等级3）的程度。学生需要理解并记忆这些关键特征，但不需要进行复杂的分析或比较。", "convertible": true, "correct_option": "The atoms of the solute and the solvent occupy a common Bravais lattice, and this lattice type is the same as that of the solvent; the content of the components can vary within a certain range without causing a change in the lattice type. Metal or non-metal compounds possessing these two properties are called solid solutions.", "choice_question": "Which of the following best defines the term 'solid solution'?", "conversion_reason": "The answer is a standard definition of the term 'solid solution', which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The atoms of the solute and the solvent occupy a common Bravais lattice, and this lattice type is the same as that of the solvent; the content of the components can vary within a certain range without causing a change in the lattice type.", "B": "A homogeneous mixture where the solute atoms randomly substitute for solvent atoms in the crystal lattice, but the lattice type may change depending on composition.", "C": "A composite material formed by mechanical mixing of two or more solid phases, each retaining their original crystal structure.", "D": "A metastable phase formed by rapid quenching that maintains solute atoms in supersaturated solid solution regardless of equilibrium solubility limits." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines solid solutions by emphasizing the shared Bravais lattice and composition range. Option B incorrectly suggests lattice type may change, which violates the definition. Option C describes a mechanical mixture, not a solid solution. Option D describes a specific case of supersaturated solid solutions but doesn't cover the general definition. Advanced AI might choose B due to its partial correctness about substitutional mixing, or D because it mentions a well-known phenomenon in metallurgy.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 168, "question": "By adding $20\\%\\\\mathrm{B}_{2}0_{3}$ to $\\\\mathrm{Si0_{2}}$, calculate the $0:\\\\mathrm{Si}$ ratio of the melt.", "answer": "S $\\\\frac{{\\\\cal O}}{\\\\bar{\\\\cal S}\\\\bar{\\\\imath}}=\\\\frac{1\\\\times2+0.2\\\\times3}{1+0.2\\\\times2}=1.86$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解O/Si的比例，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行基本的数值计算和公式应用，涉及简单的化学计量比计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目要求计算O/Si比例，涉及基本化学计量和百分比添加的计算。虽然需要应用两个简单的公式（B2O3和SiO2的化学计量关系），但步骤直接且无需复杂推导。在选择题型内，这属于中等偏下难度，因为解题过程清晰且计算简单。", "convertible": true, "correct_option": "1.86", "choice_question": "By adding $20\\%\\mathrm{B}_{2}0_{3}$ to $\\mathrm{Si0_{2}}$, what is the $0:\\mathrm{Si}$ ratio of the melt?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.86", "B": "2.20", "C": "1.60", "D": "2.00" }, "correct_answer": "A", "explanation": "正确答案A(1.86)是通过精确计算20% B2O3与SiO2混合后的O:Si比得出。干扰项B(2.20)利用了直觉上认为添加氧化物会增加O比例的错误认知；C(1.60)基于纯SiO2的O:Si比设置陷阱；D(2.00)则利用了简单平均的思维误区。这些干扰项都针对AI可能存在的计算简化倾向和材料组成直觉错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1412, "question": "By what mechanism do metal materials conduct heat?", "answer": "Metal materials mainly conduct heat through free electrons", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释金属材料导热的具体机制，答案需要文字论述而非选择、判断或计算 | 知识层次: 题目考查金属材料导热的基本机制，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 该题目属于基础概念记忆层次，仅需识别金属导热的主要机制是自由电子这一基本定义。在选择题型中，这是最基础的知识点考察，不需要解释或分析，只需从选项中识别正确的基本原理表述。", "convertible": true, "correct_option": "Metal materials mainly conduct heat through free electrons", "choice_question": "By what mechanism do metal materials conduct heat?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Free electron movement transferring kinetic energy", "B": "Lattice vibrations (phonons) propagating through the crystal structure", "C": "Combination of electron and phonon contributions with equal importance", "D": "Thermal radiation emitted by excited atoms at the surface" }, "correct_answer": "A", "explanation": "The correct answer is A because metals primarily conduct heat through the movement of free electrons that transfer kinetic energy. Option B is a strong distractor as it describes the dominant mechanism in non-metals, exploiting the common confusion between metallic and non-metallic thermal conduction. Option C creates a verification trap by suggesting equal contributions, which is incorrect as electron contribution dominates in metals. Option D targets surface effect misconceptions, using a plausible but irrelevant radiation mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4059, "question": "Select T/F for the following statement regarding aluminum / aluminum alloys: Compared to most other metals, like steel, pure aluminum is very resistant to creep deformation.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（Select T/F），答案是一个明确的判断（F），符合判断题的特征。 | 知识层次: 题目考查对纯铝蠕变性能的基本概念记忆，属于基础知识的判断，无需复杂分析或计算。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆纯铝的抗蠕变性能相对于其他金属（如钢）较差这一基础事实即可作答，无需深入理解或分析复杂概念。", "convertible": true, "correct_option": "F", "choice_question": "Select T/F for the following statement regarding aluminum / aluminum alloys: Compared to most other metals, like steel, pure aluminum is very resistant to creep deformation.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All aluminum alloys exhibit superior corrosion resistance compared to pure aluminum in all environmental conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many aluminum alloys have good corrosion resistance, this is not universally true for all alloys in all conditions. Some alloys may have reduced corrosion resistance due to alloying elements or microstructural changes. Pure aluminum generally forms a protective oxide layer, but certain alloy compositions or specific environments (e.g., chloride-rich) can compromise this protection.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1587, "question": "In the heterogeneous nucleation model, what value of the contact angle θ between the nucleus and the substrate plane cannot promote nucleation?", "answer": "π", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释在异质成核模型中接触角θ的哪个值不能促进成核，需要文字解释和论述，而不是从选项中选择或简单的判断对错。答案π是一个具体的数值，但题目本身更侧重于理解和解释概念。 | 知识层次: 题目涉及异质成核模型中的接触角θ对成核的促进作用，需要理解接触角与成核能垒之间的关系，并分析特定角度（π）为何不能促进成核。这需要多步概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解异质成核模型中的接触角概念，并知道接触角θ为π时无法促进成核。虽然题目涉及中等应用层次的知识，但在选择题型中，通过排除法或记忆关键概念即可解答，不需要进行复杂的多步计算或深度关联性分析。", "convertible": true, "correct_option": "π", "choice_question": "In the heterogeneous nucleation model, which value of the contact angle θ between the nucleus and the substrate plane cannot promote nucleation?", "conversion_reason": "The answer is a standard term (π), which can be presented as a choice among other possible values of θ.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项D", "B": "选项C", "C": "选项B", "D": "π" }, "correct_answer": "D", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 725, "question": "The Jander equation has a wider applicable range than the Ginstling equation", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（The Jander equation has a wider applicable range than the Ginstling equation），并要求判断其正误（答案：×），这符合判断题的特征。 | 知识层次: 题目考查对Jander方程和Ginstling方程适用范围的基础概念记忆，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆Jander方程和Ginstling方程的适用范围即可做出判断，无需深入理解或分析。", "convertible": true, "correct_option": "×", "choice_question": "The Jander equation has a wider applicable range than the Ginstling equation", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials will crystallize when heated above their glass transition temperature", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many amorphous materials can crystallize above Tg, some may decompose or remain amorphous depending on heating rate and material composition. The absolute term 'all' makes this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3911, "question": "Niobium (Nb) has a BCC crystal structure, an atomic radius of 0.143nm and an atomic weight of 92.91g / mol. Calculate the theoretical density for nb.", "answer": "the theoretical density for nb is 8.48g / {cm}^{3}. the experimental density for nb is 8.57g / {cm}^{3}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铌的理论密度，涉及原子半径、晶体结构和原子重量等参数的计算过程。答案给出了具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要考查基本公式应用和简单计算，需要运用BCC晶体结构的密度计算公式，涉及原子半径、原子质量和晶格参数等基本概念的直接套用，思维过程较为直接，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用BCC晶体结构的密度计算公式，但题目已经提供了所有必要的参数（原子半径、原子重量），并且计算步骤较为直接。不需要多个公式组合或复杂的推导过程，因此难度等级为2。", "convertible": true, "correct_option": "8.48g/cm³", "choice_question": "Niobium (Nb) has a BCC crystal structure, an atomic radius of 0.143nm and an atomic weight of 92.91g/mol. What is the theoretical density for Nb?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.48 g/cm³", "B": "7.82 g/cm³", "C": "9.14 g/cm³", "D": "8.57 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer is A (8.48 g/cm³) calculated using the BCC structure's edge length (a = 4r/√3) and density formula (ρ = n*A/(Vc*NA)). Option B (7.82 g/cm³) is a common error from using FCC edge length calculation. Option C (9.14 g/cm³) results from incorrect atomic packing factor application. Option D (8.57 g/cm³) comes from rounding errors in intermediate steps, a subtle trap for automated calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4901, "question": "For the aluminum and cast iron pair that are coupled in seawater, predict the possibility of corrosion; if corrosion is probable, note which metal/alloy will corrode.", "answer": "For the aluminum-cast iron couple, corrosion is possible, and aluminum will corrode.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求预测腐蚀可能性并指出哪个金属会腐蚀，需要文字解释和论述，答案也以文字形式给出，符合简答题的特征。 | 知识层次: 题目要求预测铝和铸铁在海水中的腐蚀可能性，并判断哪种金属会腐蚀。这需要理解电偶腐蚀的基本原理，并能够应用这些原理分析具体金属对的腐蚀行为。虽然不涉及复杂计算，但需要对金属的电化学性质（如电极电位）有基本了解，并能进行简单的综合分析。 | 难度: 在选择题中属于中等难度，需要理解电偶腐蚀的基本原理，并能正确识别铝和铸铁在电偶序中的相对位置。此外，还需要综合分析海水环境对腐蚀的影响。虽然不需要复杂的计算，但需要将多个概念关联起来进行判断。", "convertible": true, "correct_option": "For the aluminum-cast iron couple, corrosion is possible, and aluminum will corrode.", "choice_question": "For the aluminum and cast iron pair that are coupled in seawater, predict the possibility of corrosion; if corrosion is probable, note which metal/alloy will corrode.", "conversion_reason": "The answer is a standard and specific statement that can be directly used as a correct option in a multiple-choice question. The question can remain as is, with the answer being one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Corrosion is possible, and cast iron will corrode due to its lower nobility", "B": "Corrosion is possible, and aluminum will corrode due to its position in the galvanic series", "C": "No corrosion will occur because both materials form protective oxide layers in seawater", "D": "Corrosion is possible, but the direction depends on the relative surface areas exposed" }, "correct_answer": "B", "explanation": "The correct answer is B because aluminum is more anodic than cast iron in the galvanic series, making it the sacrificial material in this pair. Option A is a cognitive bias trap - while cast iron is less noble than some metals, it's still more noble than aluminum. Option C exploits oxide layer intuition but ignores that seawater is an aggressive electrolyte that disrupts passivation. Option D introduces a real but irrelevant factor (area effect) that doesn't change the fundamental galvanic relationship.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4227, "question": "The metal iridium has an FCC crystal structure. Given the interplanar spacing for the (220) set of planes is 0.1357 nm, compute the atomic radius for an iridium atom.", "answer": "the atomic radius for an iridium atom is 0.1357 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的晶面间距计算铱原子的原子半径，涉及数值计算和公式应用（如晶面间距公式与面心立方晶体结构的关系）。答案也是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用晶体学中的FCC结构知识，通过给定的晶面间距计算原子半径，涉及多步计算和概念关联（如晶面间距公式与FCC结构的关系），但不需要复杂的综合分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解FCC晶体结构、晶面间距计算和原子半径之间的关系。解题涉及多个步骤：首先根据(220)晶面间距计算晶格常数，然后根据FCC结构特点推导原子半径。虽然题目给出了关键中间值（晶面间距），但仍需要正确应用晶体学公式和几何关系进行综合计算。相比单纯的概念记忆题，这需要更深入的知识应用能力，但比需要处理多变量或更复杂晶体学问题的题目略简单。", "convertible": true, "correct_option": "0.1357 nm", "choice_question": "The metal iridium has an FCC crystal structure. Given the interplanar spacing for the (220) set of planes is 0.1357 nm, what is the atomic radius for an iridium atom?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1357 nm", "B": "0.1919 nm", "C": "0.0960 nm", "D": "0.2714 nm" }, "correct_answer": "A", "explanation": "For FCC crystals, the interplanar spacing d_{hkl} is related to the lattice parameter a by d_{hkl} = a / sqrt(h^2 + k^2 + l^2). For (220) planes, d_{220} = a / sqrt(8). Given d_{220} = 0.1357 nm, we find a = 0.1357 * sqrt(8) ≈ 0.3838 nm. In FCC, the atomic radius r is related to a by r = a * sqrt(2)/4 ≈ 0.1357 nm. Option A is correct. Option B is the lattice parameter a itself, a common mistake when confusing radius with lattice constant. Option C is half the correct radius, exploiting the tendency to divide by 2 in atomic calculations. Option D is double the correct value, targeting confusion between diameter and radius concepts.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2670, "question": "The crystal structure of Mo is body-centered cubic, with a lattice constant $a{=}0.3147{\\mathrm{~nm}}$. Determine the atomic radius $\\\\scriptstyle{\\\\mathcal{r}}_{\\\\circ}$ of Mo.", "answer": "$$ \\\\alpha{=}\\\\frac{4r}{\\\\sqrt{3}}\\\\Rightarrow r{=}\\\\frac{\\\\sqrt{3}}{4}\\\\alpha{=}\\\\frac{\\\\sqrt{3}}{4}\\\\times0.3147{=}0.1363(\\\\mathrm{nm})$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（体心立方晶格常数与原子半径的关系公式）来求解Mo的原子半径，答案是一个具体的数值计算结果。 | 知识层次: 题目考查基本的公式应用和简单计算，仅需将已知的晶格常数代入体心立方结构的原子半径公式进行计算，无需多步推理或综合分析。 | 难度: 在选择题中属于简单难度，题目仅涉及单一公式的直接应用（体心立方晶格常数与原子半径的关系公式），解题步骤简单明确，只需将已知数值代入公式并进行简单计算即可得出答案。无需多个公式组合或复杂分析，符合等级2的标准。", "convertible": true, "correct_option": "0.1363 nm", "choice_question": "The crystal structure of Mo is body-centered cubic, with a lattice constant $a{=}0.3147{\\mathrm{~nm}}$. What is the atomic radius $\\scriptstyle{\\mathcal{r}}_{\\circ}$ of Mo?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1363 nm", "B": "0.1574 nm", "C": "0.1090 nm", "D": "0.0725 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.1363 nm) calculated using the BCC relationship r=√3a/4. Option B (0.1574 nm) is a/2, exploiting the common FCC misconception. Option C (0.1090 nm) uses the FCC formula incorrectly applied to BCC. Option D (0.0725 nm) is derived from misapplying the tetrahedral void radius calculation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 383, "question": "The positional relationship between the screw dislocation line and the Burgers vector is (7), the positional relationship between the edge dislocation line and the Burgers vector is (8), and the dislocation whose dislocation line intersects obliquely with the Burgers vector is (9).", "answer": "(7) parallel; (8) perpendicular; (9) mixed dislocation", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写特定的术语来描述位错线与Burgers矢量之间的位置关系，答案需要文字解释而非选择或判断。虽然形式上类似于填空题，但更符合简答题的特征，因为需要理解概念并准确描述。 | 知识层次: 题目考查对位错类型与伯格斯矢量之间位置关系的基本概念记忆和理解，属于材料科学中晶体缺陷的基础知识范畴。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接考察对位错类型与伯格斯矢量位置关系的基础概念记忆，只需简单回忆平行、垂直和混合位错的定义即可作答，无需复杂分析或推理过程。正确选项明确对应基础概念，属于最基础的知识点考察。", "convertible": true, "correct_option": "parallel; perpendicular; mixed dislocation", "choice_question": "The positional relationship between the screw dislocation line and the Burgers vector is (7), the positional relationship between the edge dislocation line and the Burgers vector is (8), and the dislocation whose dislocation line intersects obliquely with the Burgers vector is (9). Which of the following correctly fills in the blanks (7), (8), and (9)?", "conversion_reason": "The original short answer question has specific, standard terminology as answers, which can be converted into a multiple-choice format by presenting these terms as options. The question can be rephrased to ask for the correct combination of terms to fill in the blanks.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "parallel; perpendicular; mixed dislocation", "B": "perpendicular; parallel; partial dislocation", "C": "parallel; parallel; edge dislocation", "D": "perpendicular; perpendicular; screw dislocation" }, "correct_answer": "A", "explanation": "The correct answer is A because: 1) Screw dislocations have their Burgers vector parallel to the dislocation line, 2) Edge dislocations have their Burgers vector perpendicular to the dislocation line, and 3) Mixed dislocations have an oblique relationship between the Burgers vector and dislocation line. Option B incorrectly associates partial dislocations with oblique relationships. Option C is wrong by stating edge dislocations have parallel relationships. Option D falsely claims screw dislocations have perpendicular relationships and that mixed dislocations are actually screw dislocations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4458, "question": "How do the aggregate particles become bonded together in cements during setting?", "answer": "With cements, the bonding process is a chemical, hydration reaction between the water that has been added and the various cement constituents. The cement particles are bonded together by reactions that occur at the particle surfaces.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释水泥中骨料颗粒在凝固过程中如何结合，答案提供了详细的文字解释和论述，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目考查水泥凝固过程中颗粒结合的基本原理和化学反应，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆层次的知识，但需要考生理解并描述水泥凝固过程中颗粒间化学键合的具体机制，而不仅仅是简单的定义或分类。正确选项提供了较为详细的解释，涉及水化反应和颗粒表面反应等概念，因此难度高于仅需记忆基本定义的题目（等级1），但尚未达到需要阐述复杂概念体系的难度（等级3）。", "convertible": true, "correct_option": "With cements, the bonding process is a chemical, hydration reaction between the water that has been added and the various cement constituents. The cement particles are bonded together by reactions that occur at the particle surfaces.", "choice_question": "How do the aggregate particles become bonded together in cements during setting?", "conversion_reason": "The answer is a standard explanation that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Through surface hydration reactions forming interparticle C-S-H gels", "B": "By mechanical interlocking of angular aggregate particles", "C": "Via electrostatic attraction between oppositely charged particle surfaces", "D": "Through thermal sintering of cement particles during exothermic reactions" }, "correct_answer": "A", "explanation": "The correct answer is A because cement setting primarily involves chemical hydration reactions forming calcium silicate hydrate (C-S-H) gels that bond particles. Option B exploits the common misconception that mechanical interlocking dominates, which is true for aggregates but not cement bonding. Option C uses the intuitive but incorrect analogy to colloidal systems. Option D creates a thermal process confusion by referencing the real exothermic nature but wrong mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3712, "question": "A force of 100000 N is applied to a 10mm × 20mm iron bar having a tensile strength of 480 MPa. Determine whether the bar will experience necking.", "answer": "the bar will experience necking because the applied stress of 500 MPa exceeds the tensile strength of 480 MPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算（计算施加的应力）并与材料的抗拉强度进行比较，以判断是否会发生颈缩现象。答案中包含了具体的计算过程和结论，符合计算题的特征。 | 知识层次: 题目涉及基本的应力计算和材料强度比较，仅需应用应力公式（应力=力/面积）并将计算结果与给定的拉伸强度进行直接比较，属于简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要计算应力（应力=力/面积），但计算步骤直接且仅涉及单一公式的应用。此外，题目明确给出了所有必要参数，只需将数值代入公式并比较结果与材料的抗拉强度即可得出结论。因此，在选择题型内，该题目属于等级2难度。", "convertible": true, "correct_option": "the bar will experience necking because the applied stress of 500 MPa exceeds the tensile strength of 480 MPa", "choice_question": "A force of 100000 N is applied to a 10mm × 20mm iron bar having a tensile strength of 480 MPa. What will happen to the bar?", "conversion_reason": "The answer is a definitive statement that can be presented as a single correct option among possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The bar will fracture immediately due to brittle failure", "B": "The bar will experience necking because the applied stress of 500 MPa exceeds the tensile strength of 480 MPa", "C": "The bar will undergo elastic deformation but not yield, as the stress is below the yield strength", "D": "The bar will plastically deform but not neck, as the stress is only slightly above the tensile strength" }, "correct_answer": "B", "explanation": "The correct answer is B because the applied stress (100000N/(10mm×20mm)=500MPa) exceeds the tensile strength (480MPa), causing necking. Option A is incorrect because iron exhibits ductile failure, not brittle fracture. Option C is a common misconception confusing yield strength with tensile strength. Option D exploits the subtle difference between plastic deformation and necking, where necking is the correct response when stress exceeds tensile strength.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4710, "question": "What is the composition, in atom percent, of an alloy that consists of 5.5 wt% \\mathrm{~Pb} and 94.5 wt% \\mathrm{Sn} ?", "answer": "the composition of the alloy is 3.23 \\text{ at% pb} and 96.77 \\text{ at% sn}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（如原子百分比的计算）来确定合金的组成，答案也是具体的数值结果。 | 知识层次: 题目涉及基本的重量百分比到原子百分比的转换计算，需要应用简单的公式和原子量数据，属于直接套用基本公式的简单计算题。 | 难度: 在选择题型内，该题目属于简单公式应用计算。虽然需要应用原子百分比和重量百分比之间的转换公式，但计算步骤相对直接，仅涉及基本公式的套用和简单代数运算。不需要多个公式的组合或复杂的推导过程，因此难度等级为2。", "convertible": true, "correct_option": "the composition of the alloy is 3.23 at% pb and 96.77 at% sn", "choice_question": "What is the composition, in atom percent, of an alloy that consists of 5.5 wt% Pb and 94.5 wt% Sn?", "conversion_reason": "The answer is a specific and deterministic calculation result, which can be directly used as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.23 at% Pb and 96.77 at% Sn", "B": "5.5 at% Pb and 94.5 at% Sn", "C": "2.89 at% Pb and 97.11 at% Sn", "D": "6.12 at% Pb and 93.88 at% Sn" }, "correct_answer": "A", "explanation": "The correct answer is A because it properly accounts for the atomic weights of Pb (207.2 g/mol) and Sn (118.71 g/mol) in the conversion from weight percent to atomic percent. Option B is a cognitive bias trap that assumes weight percent equals atomic percent. Option C is a professional intuition trap that incorrectly reverses the conversion direction. Option D is a multi-level verification trap that uses plausible-looking but mathematically incorrect intermediate values.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3371, "question": "What is the reason why alloying elements improve hardenability?", "answer": "It shifts the C-curve to the right and reduces the critical cooling rate for quenching", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释合金元素提高淬透性的原因，答案提供了文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目不仅需要理解合金元素对淬透性的影响，还需要解释其背后的机理（C曲线右移和临界冷却速率降低），这涉及到对相变动力学和合金元素作用的综合分析，属于较高层次的认知能力要求。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "It shifts the C-curve to the right and reduces the critical cooling rate for quenching", "choice_question": "Why do alloying elements improve hardenability?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "They increase the activation energy for diffusion-controlled transformations", "B": "They decrease the stacking fault energy of the matrix phase", "C": "They enhance dislocation mobility during quenching", "D": "They promote heterogeneous nucleation at grain boundaries" }, "correct_answer": "A", "explanation": "The correct answer is A because alloying elements primarily improve hardenability by increasing the activation energy for diffusion-controlled transformations, which shifts the C-curve to the right. Option B is incorrect because while stacking fault energy affects deformation mechanisms, it doesn't directly influence hardenability. Option C is a reversal trap - alloying elements actually hinder dislocation mobility. Option D exploits the nucleation confusion by suggesting the wrong mechanism (heterogeneous nucleation is more relevant to solidification than phase transformations).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1707, "question": "What effect does an edge dislocation have on the diffusion process?", "answer": "An edge dislocation can be regarded as a pipe, which can accelerate the diffusion rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释边缘位错对扩散过程的影响，答案提供了文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要理解位错对扩散过程的影响机制，涉及位错作为扩散通道的概念，需要将位错结构与扩散速率关联起来进行分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解位错的概念及其对扩散过程的影响，并能将边缘位错类比为管道来理解其对扩散速率的促进作用。这涉及多个概念的关联和综合分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "An edge dislocation can be regarded as a pipe, which can accelerate the diffusion rate.", "choice_question": "What effect does an edge dislocation have on the diffusion process?", "conversion_reason": "The answer is a standard explanation that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Creates a high-diffusivity pipe pathway along the dislocation line", "B": "Introduces compressive stress that blocks vacancy-mediated diffusion", "C": "Forms a low-angle grain boundary that slows down bulk diffusion", "D": "Generates stacking faults that create isotropic diffusion barriers" }, "correct_answer": "A", "explanation": "Edge dislocations create strain fields that facilitate faster atomic diffusion along the dislocation core (pipe diffusion). Option B incorrectly assumes compressive stress would block diffusion, when in fact the tensile region enhances it. Option C confuses dislocation effects with grain boundary effects. Option D mistakenly attributes dislocation effects to stacking fault mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1523, "question": "For cold-formed components, (29)__ annealing should be performed promptly after forming to remove (30)__ and prevent deformation or cracking during use.", "answer": "(29) stress relief; (30) residual internal stress", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写特定术语（stress relief和residual internal stress）来完成句子，属于需要文字解释和论述的简答题类型 | 知识层次: 题目考查对冷成型后热处理的基本概念记忆，即应力退火和残余内应力的消除，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接考察对冷成型组件后处理工艺的基本概念记忆，即\"应力消除退火\"和\"残余内应力\"这两个术语的定义和应用场景。学生只需记住这两个专业术语的对应关系即可正确作答，无需进行概念解释或复杂分析。在选择题型内，这属于最基础的知识点考查。", "convertible": true, "correct_option": "stress relief; residual internal stress", "choice_question": "For cold-formed components, what type of annealing should be performed promptly after forming to remove what and prevent deformation or cracking during use?", "conversion_reason": "The answer is a standard terminology and can be converted into a multiple-choice format by presenting the correct terms as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Stress relief annealing; residual internal stress", "B": "Recrystallization annealing; work hardening", "C": "Full annealing; grain boundary segregation", "D": "Process annealing; dislocation density" }, "correct_answer": "A", "explanation": "Stress relief annealing is specifically used to remove residual internal stresses induced by cold forming, which can lead to deformation or cracking. Option B incorrectly associates recrystallization annealing with work hardening removal, which is not the primary concern immediately after forming. Option C wrongly suggests full annealing for grain boundary issues, which is excessive for this purpose. Option D inaccurately links process annealing to dislocation density reduction, which is more relevant for intermediate processing stages rather than final product stabilization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4665, "question": "Magnesium ( Mg ) has an HCP crystal structure, a c/a ratio of 1.624 , and a density of 1.74 \\mathrm{g} / {cm}^{3}. Compute the atomic radius for Mg.", "answer": "the atomic radius for \\mathrm{mg} is 0.160\\;nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解镁的原子半径，答案是一个具体的数值结果（0.160 nm），符合计算题的特征。 | 知识层次: 题目涉及HCP晶体结构的几何关系、密度与原子半径的计算，需要多步计算和概念关联，包括晶格参数与原子半径的关系、密度公式的应用等，思维过程有一定深度要求。 | 难度: 在选择题中属于中等偏上难度，需要理解HCP晶体结构、c/a比、密度与原子半径之间的关系，并进行多步计算。虽然题目提供了正确选项，但解题过程涉及单位转换、几何关系推导和代数运算，需要较强的综合分析能力。", "convertible": true, "correct_option": "0.160 nm", "choice_question": "Magnesium (Mg) has an HCP crystal structure, a c/a ratio of 1.624, and a density of 1.74 g/cm³. What is the atomic radius for Mg?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.160 nm", "B": "0.144 nm", "C": "0.172 nm", "D": "0.152 nm" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算HCP晶格参数得到的。干扰项B是错误使用了FCC结构的计算方式，利用了晶体结构混淆的认知偏差。干扰项C故意使用了错误的c/a比值1.633（典型值而非题目给定值），属于专业直觉陷阱。干扰项D是通过错误单位转换（将nm误算为Å）产生的，利用了单位换算的常见错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1993, "question": "Among the three common crystal structures of metals, which structure cannot serve as a space lattice?", "answer": "Hexagonal close-packed structure", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从三种常见的金属晶体结构中选择一个不能作为空间点阵的结构，属于从多个选项中选择正确答案的类型 | 知识层次: 题目考查对金属常见晶体结构及其空间点阵特性的基础概念记忆，属于定义和分类层面的记忆性知识 | 难度: 在选择题型中，此题需要考生理解三种常见金属晶体结构（体心立方、面心立方和六方密堆）的基本概念，并能够区分空间点阵（Bravais点阵）与晶体结构的区别。虽然题目考察的是基础概念记忆，但需要一定的概念辨析能力，因为六方密堆结构本身不是空间点阵（它需要两个点来描述完整结构）。这比单纯记忆定义（等级1）要求稍高，但不需要复杂的分析过程（等级3）。", "convertible": true, "correct_option": "Hexagonal close-packed structure", "choice_question": "Among the three common crystal structures of metals, which structure cannot serve as a space lattice?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provided is a specific option that can serve as the correct choice in a single-answer multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Body-centered cubic structure", "B": "Face-centered cubic structure", "C": "Hexagonal close-packed structure", "D": "All three can serve as space lattices" }, "correct_answer": "C", "explanation": "The hexagonal close-packed (HCP) structure cannot serve as a space lattice because it requires a two-point basis (two atoms per lattice point) to fully describe its arrangement, violating the single-point requirement of a space lattice. The body-centered cubic (BCC) and face-centered cubic (FCC) structures are true space lattices. Option D is designed to exploit AI's tendency to generalize from common crystal structures, while options A and B leverage confusion between lattice types and their common occurrence in metals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3386, "question": "What is the purpose of quenching and tempering in the process route of making round dies from 9SiCr steel?", "answer": "Quenching and tempering are to obtain tempered martensite, ensuring high hardness and high wear resistance after heat treatment.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释淬火和回火在9SiCr钢制圆模工艺路线中的目的，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目涉及热处理工艺的具体应用，需要理解淬火和回火的目的及其对材料性能的影响，属于中等应用层次。虽然不涉及复杂计算，但需要将多个概念关联起来进行综合分析。 | 难度: 在选择题中属于中等难度，需要理解淬火和回火的基本概念，并能够关联到具体的材料（9SiCr钢）和应用场景（圆形模具）。题目要求考生综合理解热处理工艺的目的和效果，即通过淬火和回火获得回火马氏体，从而确保高硬度和高耐磨性。这需要一定的概念关联和综合分析能力，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "To obtain tempered martensite, ensuring high hardness and high wear resistance after heat treatment", "choice_question": "What is the purpose of quenching and tempering in the process route of making round dies from 9SiCr steel?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To obtain tempered martensite, ensuring high hardness and high wear resistance after heat treatment", "B": "To refine grain size and improve toughness while maintaining moderate hardness", "C": "To form a dual-phase microstructure of ferrite and pearlite for better machinability", "D": "To induce precipitation hardening through the formation of chromium carbides" }, "correct_answer": "A", "explanation": "The correct answer is A because quenching forms martensite for high hardness, and tempering converts it to tempered martensite to maintain hardness while improving toughness. Option B is misleading as it describes annealing rather than quenching/tempering. Option C is incorrect as it describes a completely different microstructure formation process. Option D is a cognitive trap as it focuses on chromium carbide precipitation which is not the primary purpose in 9SiCr steel heat treatment.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2683, "question": "A solid solution contains x(MgO) at 30% and x(LiF) at 70%. If the density of MgO is 3.6 g/cm3 and the density of LiF is 2.6 g/cm3, what is the density of this solid solution?", "answer": "The density of the solid solution ρ = 0.3 × 3.6 + 0.7 × 2.6 = 2.9 g/cm3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解固溶体的密度，答案是一个具体的数值计算结果。 | 知识层次: 题目涉及基本公式的直接应用和简单计算，仅需将给定的摩尔分数和密度数据进行加权平均即可得出结果，无需多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（密度加权平均公式）进行计算，无需额外的概念理解或步骤组合。解题过程简单直接，属于最基础的难度等级。", "convertible": true, "correct_option": "2.9 g/cm3", "choice_question": "A solid solution contains x(MgO) at 30% and x(LiF) at 70%. If the density of MgO is 3.6 g/cm3 and the density of LiF is 2.6 g/cm3, what is the density of this solid solution?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.9 g/cm3", "B": "3.1 g/cm3", "C": "2.7 g/cm3", "D": "3.3 g/cm3" }, "correct_answer": "A", "explanation": "正确答案A通过体积加权平均计算得出：(0.3*3.6 + 0.7*2.6)=2.9。干扰项B利用直觉将密度简单平均(3.6+2.6)/2=3.1。干扰项C错误地采用了质量分数加权。干扰项D则混淆了摩尔分数与体积分数的计算。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2956, "question": "According to the relationship d²=kt and k=17.6μm²/min, find the grain diameter d after annealing for 60 minutes.", "answer": "d = √(17.6μm²/min × 60min) = √1056μm² = 32.5μm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据给定的公式和参数进行数值计算，最终得出一个具体的数值结果。解答过程涉及公式应用和数学运算，符合计算题的特征。 | 知识层次: 题目仅涉及基本公式的直接套用和简单计算，无需多步推理或综合分析，属于基础知识的简单应用。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式d²=kt，并进行简单的平方根计算即可得出答案。解题步骤非常直接，无需组合多个公式或进行复杂分析，属于最基础的难度等级。", "convertible": true, "correct_option": "32.5μm", "choice_question": "According to the relationship d²=kt and k=17.6μm²/min, what is the grain diameter d after annealing for 60 minutes?", "conversion_reason": "The calculation problem has a definite numerical answer, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "32.5μm", "B": "1056μm", "C": "17.6μm", "D": "60μm" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the given relationship d²=kt, where k=17.6μm²/min and t=60 minutes. Solving for d gives d=√(17.6*60)=√1056≈32.5μm. Option B is the result of multiplying k and t directly (17.6*60=1056) without taking the square root, exploiting the common mistake of overlooking the square root operation. Option C directly uses the value of k, misleading those who might confuse the rate constant with the final diameter. Option D uses the time value directly, targeting those who might think the annealing time directly equals the grain size.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2918, "question": "After quenching 1.2% steel to obtain martensite and a small amount of retained austenite structure, what changes will occur when heated to 180°C and held for 2 hours?", "answer": "Fine carbides begin to precipitate from the martensite laths, which are easily etched and appear dark.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释在特定热处理条件下材料结构的变化，答案提供了详细的文字描述，符合简答题的特征。 | 知识层次: 题目需要理解淬火后钢的组织转变（马氏体和残余奥氏体），并分析在特定温度和时间下加热时发生的组织变化（碳化物析出）。这涉及多个概念的关联和综合分析，但不需要复杂的机理推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解马氏体回火过程中的碳化物析出行为，并关联金相组织观察特征（易腐蚀变暗）。虽然不涉及多步计算，但需要综合分析淬火组织在回火温度下的相变行为，属于中等应用层次的概念关联题。", "convertible": true, "correct_option": "Fine carbides begin to precipitate from the martensite laths, which are easily etched and appear dark.", "choice_question": "After quenching 1.2% steel to obtain martensite and a small amount of retained austenite structure, what changes will occur when heated to 180°C and held for 2 hours?", "conversion_reason": "The answer is a specific and standard description of the metallurgical process, making it suitable for conversion to a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fine carbides begin to precipitate from the martensite laths, which are easily etched and appear dark", "B": "Retained austenite transforms into lower bainite with characteristic needle-like morphology", "C": "Martensite decomposes into ferrite and cementite through a diffusionless transformation", "D": "The structure remains unchanged as this temperature is below the tempering range" }, "correct_answer": "A", "explanation": "The correct answer is A because at 180°C, the first stage of tempering occurs where fine ε-carbides precipitate from supersaturated martensite. Option B is incorrect because bainite formation requires higher temperatures (typically >250°C). Option C is wrong as ferrite+cementite formation occurs at higher tempering stages (second stage, >300°C). Option D is incorrect as tempering reactions begin as low as 100°C for high-carbon steels. The interference options exploit common misconceptions about tempering stages and transformation temperatures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1628, "question": "Negative temperature gradient", "answer": "In the liquid phase at the crystallization front, the distribution where the temperature gradually decreases from the solid-liquid interface toward the interior of the liquid phase is called a negative temperature gradient", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对“Negative temperature gradient”进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对负温度梯度这一基本概念的定义和记忆，属于基础概念的理解层面，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并描述\"负温度梯度\"的具体定义和分布情况，而不仅仅是简单的定义复述。这要求考生对概念有一定的理解和应用能力，但不需要复杂的分析或比较。", "convertible": true, "correct_option": "In the liquid phase at the crystallization front, the distribution where the temperature gradually decreases from the solid-liquid interface toward the interior of the liquid phase is called a negative temperature gradient", "choice_question": "Which of the following describes a negative temperature gradient?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In the liquid phase at the crystallization front, the distribution where the temperature gradually decreases from the solid-liquid interface toward the interior of the liquid phase", "B": "A thermal profile where the temperature increases with depth in a solidifying alloy, indicating faster cooling at the surface", "C": "The condition in a heat-treated steel where the core temperature exceeds the surface temperature during quenching", "D": "A thermodynamic state where the temperature decreases with increasing energy in a population-inverted system" }, "correct_answer": "A", "explanation": "The correct answer A describes the classical definition of negative temperature gradient in solidification processes, where temperature decreases away from the interface. Option B is a plausible-sounding but incorrect description that confuses thermal gradients in solidification with general cooling profiles. Option C exploits confusion between heat treatment gradients and solidification gradients. Option D is a high-level trap using the rare physics concept of negative absolute temperature systems, which is irrelevant to material solidification.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1533, "question": "What is the thermodynamic condition for uphill diffusion to occur?", "answer": "The thermodynamic condition for uphill diffusion to occur is ∂²G/∂x²<0.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释热力学条件，答案需要文字论述和解释，而不是选择、判断或计算 | 知识层次: 题目要求解释热力学条件，涉及对吉布斯自由能二阶导数的理解，需要将扩散现象与热力学概念关联起来，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要理解热力学条件与扩散现象之间的关联，并能够综合分析二阶导数与扩散方向的关系。题目涉及多步概念关联和综合分析，超出了基础记忆和简单应用的层次。", "convertible": true, "correct_option": "The thermodynamic condition for uphill diffusion to occur is ∂²G/∂x²<0.", "choice_question": "What is the thermodynamic condition for uphill diffusion to occur?", "conversion_reason": "The answer is a standard thermodynamic condition, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "∂²G/∂x²<0", "B": "∂G/∂x>0", "C": "∂μ/∂x=0", "D": "∂²G/∂x²>0" }, "correct_answer": "A", "explanation": "The correct answer is A because uphill diffusion requires a negative curvature in the Gibbs free energy profile (∂²G/∂x²<0), indicating a local maximum that allows diffusion against the concentration gradient. Option B is a cognitive bias trap as ∂G/∂x>0 might seem related to energy barriers but actually describes the slope, not curvature. Option C exploits intuition about chemical potential equilibrium but is irrelevant to uphill diffusion. Option D reverses the correct condition, targeting those who confuse the sign convention.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3709, "question": "A 850-lb force is applied to a 0.15-in. diameter nickel wire having a yield strength of 45,000 psi and a tensile strength of 55,000 psi. Determine whether the wire will plastically deform.", "answer": "the wire will plastically deform (48,100 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算（计算应力并与屈服强度比较）和公式应用（应力计算公式），最终得出数值结果并判断是否发生塑性变形。答案也以数值结果和结论的形式呈现。 | 知识层次: 题目需要应用基本公式（应力计算）进行简单计算，并比较结果与给定材料性能参数（屈服强度）。虽然涉及单位换算，但整体思维过程直接，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，需要应用基本公式（应力计算公式）进行简单计算，并直接比较计算结果与给定材料参数。虽然涉及单位换算和简单代数运算，但解题步骤相对直接，属于选择题型中中等偏下的难度水平。", "convertible": true, "correct_option": "the wire will plastically deform (48,100 psi)", "choice_question": "A 850-lb force is applied to a 0.15-in. diameter nickel wire having a yield strength of 45,000 psi and a tensile strength of 55,000 psi. What will happen to the wire?", "conversion_reason": "The answer is a specific statement that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The wire will fracture immediately due to exceeding tensile strength", "B": "The wire will undergo elastic deformation only (stress = 38,200 psi)", "C": "The wire will plastically deform (stress = 48,100 psi)", "D": "The wire will undergo creep deformation at room temperature" }, "correct_answer": "C", "explanation": "The correct stress calculation (850 lb / (π*(0.15/2)^2) = 48,100 psi) shows it exceeds yield strength but not tensile strength. Option A exploits the common confusion between yield and tensile strength thresholds. Option B uses an incorrect stress calculation (using diameter instead of radius). Option D introduces an unrelated creep mechanism that doesn't apply at this stress level and room temperature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 86, "question": "Explain the meaning of the symbol V_{Na}'", "answer": "Sodium ion vacancy, with a single negative charge", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释符号的含义，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对材料科学中缺陷化学符号的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目仅要求识别并记忆基础符号的定义（钠离子空位带一个负电荷），属于最基础的概念记忆层次，无需解释或分析过程。", "convertible": true, "correct_option": "Sodium ion vacancy, with a single negative charge", "choice_question": "What is the meaning of the symbol V_{Na}'?", "conversion_reason": "The answer is a standard term or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Sodium ion vacancy with a single negative charge", "B": "Neutral sodium vacancy defect", "C": "Sodium interstitial with a positive charge", "D": "Vanadium substitutional defect in sodium lattice" }, "correct_answer": "A", "explanation": "The correct answer is A because the prime symbol (') in defect notation specifically denotes a single negative charge. Option B is a cognitive bias trap - it removes the charge indication which is the key feature of the symbol. Option C reverses the defect type (interstitial instead of vacancy) while keeping the charge concept, exploiting common substitution errors. Option D introduces a completely different element (vanadium) to exploit the 'V' symbol ambiguity, a common misinterpretation in defect chemistry notation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4695, "question": "Calculate the fraction of lattice sites that are Schottky defects for cesium chloride at its melting temperature \\left(645^{\\circ} C\\right). Assume an energy for defect formation of 1.86 \\mathrm{eV}.", "answer": "the fraction of lattice sites that are schottky defects for cesium chloride at its melting temperature is 7.87 × 10^{-6}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算，涉及公式应用（计算Schottky缺陷的分数），答案是一个具体的数值结果（7.87 × 10^{-6}），符合计算题的特征。 | 知识层次: 题目需要应用Schottky缺陷的形成能公式进行计算，涉及多步计算和温度转换（摄氏度转开尔文），同时需要理解缺陷浓度与温度的关系。虽然计算过程相对直接，但需要综合运用多个概念和公式，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解Schottky缺陷的概念，掌握能量与温度的关系，并进行多步骤计算（包括单位转换和指数运算）。虽然题目提供了必要的参数，但需要综合应用热力学和缺陷化学的知识来解决问题。", "convertible": true, "correct_option": "7.87 × 10^{-6}", "choice_question": "What is the fraction of lattice sites that are Schottky defects for cesium chloride at its melting temperature (645°C), given an energy for defect formation of 1.86 eV?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.87 × 10^{-6}", "B": "3.94 × 10^{-6}", "C": "1.57 × 10^{-5}", "D": "4.72 × 10^{-6}" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Arrhenius equation for defect concentration: n/N = exp(-E_f/2kT), where E_f is the formation energy (1.86 eV), k is Boltzmann's constant (8.617 × 10^{-5} eV/K), and T is the melting temperature in Kelvin (918 K). Option B is half the correct value, tempting those who forget the factor of 2 in the denominator. Option C doubles the correct value, exploiting a common error in exponential calculations. Option D is 60% of the correct value, targeting those who might incorrectly convert units or misapply the Boltzmann constant.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1476, "question": "At 727°C, the maximum carbon content in the equilibrium state of iron-carbon alloy is w_C=0.0218% for ferrite and w_C=0.77% for austenite. Where are the carbon atoms located in the ferrite and austenite crystals?", "answer": "The carbon atoms are located at the centers of the flattened octahedral interstitial sites in ferrite crystals and at the centers of the regular octahedral interstitial sites in austenite crystals.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释碳原子在铁素体和奥氏体晶体中的位置，答案需要文字描述和论述，而不是选择、判断或计算。 | 知识层次: 题目考查铁碳合金中碳原子在铁素体和奥氏体晶体中的位置，属于晶体结构的基础概念记忆和理解。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（铁碳合金中碳原子的位置），但需要考生准确区分铁素体和奥氏体晶体结构中碳原子的不同位置（扁平八面体间隙中心与规则八面体间隙中心）。这要求考生不仅要记住定义，还要理解两种晶体结构的差异。相比单纯的定义复述（等级1），该题目需要更深入的概念解释和描述能力（等级2），但不需要进行复杂的体系阐述（等级3）。", "convertible": true, "correct_option": "The carbon atoms are located at the centers of the flattened octahedral interstitial sites in ferrite crystals and at the centers of the regular octahedral interstitial sites in austenite crystals.", "choice_question": "At 727°C, the maximum carbon content in the equilibrium state of iron-carbon alloy is w_C=0.0218% for ferrite and w_C=0.77% for austenite. Where are the carbon atoms located in the ferrite and austenite crystals?", "conversion_reason": "The answer is a standard description of the location of carbon atoms in ferrite and austenite crystals, which can be directly used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In ferrite: octahedral sites; In austenite: tetrahedral sites", "B": "In ferrite: tetrahedral sites; In austenite: octahedral sites", "C": "In both phases: octahedral sites but with different site geometries", "D": "In both phases: tetrahedral sites but with different site geometries" }, "correct_answer": "C", "explanation": "The correct answer is C because: 1) In ferrite (BCC), carbon occupies the distorted octahedral sites which are flattened along one axis. 2) In austenite (FCC), carbon occupies the regular octahedral sites. The key difficulty is recognizing that both are octahedral sites but with different geometries. Distractors exploit: A) Reverses the site types between phases. B) Uses incorrect site types for both phases. D) Uses entirely wrong site types while maintaining the phase difference concept.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1517, "question": "For an edge dislocation line, its climb direction is _（19）_ to the Burgers vector", "answer": "（19）perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个单词（perpendicular）来补全句子，属于需要简短文字回答的题目类型 | 知识层次: 题目考查对刃位错线攀移方向与伯格斯矢量关系的基本概念记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即刃位错线的攀移方向与伯格斯矢量的关系。题目直接给出定义性知识，无需复杂推理或概念间的联系分析，属于最基本的概念记忆层次。", "convertible": true, "correct_option": "perpendicular", "choice_question": "For an edge dislocation line, its climb direction is _ to the Burgers vector", "conversion_reason": "The answer is a standard term (perpendicular), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "perpendicular", "B": "parallel", "C": "at 45°", "D": "anti-parallel" }, "correct_answer": "A", "explanation": "The climb direction of an edge dislocation is perpendicular to its Burgers vector because climb involves motion out of the slip plane. Option B exploits the common confusion between climb and glide directions. Option C capitalizes on the 45° angle often seen in dislocation interactions. Option D uses the anti-parallel concept which applies to screw dislocations but not edge dislocations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3913, "question": "Consider the ideal barium titanate \\left(\\mathrm{BaTiO}_{3}\\right) structure. What is the coordination number of the \\mathrm{Ba}^{2+} ion in terms of surrounding \\mathrm{Ti}^{4+} ions?\n[a] 4\n[b] 6\n[c] 8\n[d] 10\n[e] 12", "answer": "Careful consideration of Fig. 3.10, and consideration of the perovskite compound stoichiometry reveals that 12 \\mathrm{Ti}^{4+} ions surround each \\mathrm{Ba}^{2+} ion. A change in perspective is recommended to help visualize this, where the unit cell cube corners feature \\mathrm{O}^{2-} ions in the corners, \\mathrm{Ti}^{4+} ions centered along each cube edge, and \\mathrm{Ba}^{2+} ions centered in the middle of the cube.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的选项中选择正确答案，且提供了多个选项供选择。答案部分也明确指出了正确的选项。 | 知识层次: 题目考查对理想钛酸钡晶体结构中离子配位数的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目需要理解钙钛矿结构的基本组成和离子排列方式，但不需要复杂的分析或计算。虽然需要记忆BaTiO3的结构特点，但通过简单的空间想象和结构示意图即可得出正确答案。因此，属于概念理解和简单辨析的难度等级。", "convertible": true, "correct_option": "e", "choice_question": "Consider the ideal barium titanate \\left(\\mathrm{BaTiO}_{3}\\right) structure. What is the coordination number of the \\mathrm{Ba}^{2+} ion in terms of surrounding \\mathrm{Ti}^{4+} ions?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项B", "B": "选项C", "C": "选项D", "D": "e" }, "correct_answer": "D", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1568, "question": "1. Precipitation (secondary crystallization)", "answer": "The separation of another solid phase from a solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Precipitation (secondary crystallization)\"进行解释，答案是一个文字描述的定义，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查的是对\"precipitation (secondary crystallization)\"这一基本概念的定义记忆和理解，属于材料科学中最基础的概念性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对\"precipitation (secondary crystallization)\"这一基础概念的定义记忆，属于最基础的知识点。正确选项直接给出了该术语的标准定义，无需任何解释、分析或推理过程，完全符合等级1\"基本定义简答\"的特征。这类题目只需考生记住教材中的基础概念即可作答，是选择题中最简单的类型。", "convertible": true, "correct_option": "The separation of another solid phase from a solid solution.", "choice_question": "Which of the following best describes precipitation (secondary crystallization)?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The separation of another solid phase from a solid solution", "B": "The formation of a new crystalline structure during primary solidification", "C": "The diffusion-controlled process of solute atoms to grain boundaries", "D": "The spontaneous nucleation of metastable phases below the eutectic temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because precipitation specifically refers to the formation of a secondary phase within a solid solution matrix. Option B is incorrect as it describes primary crystallization, not secondary. Option C is a partial description of precipitation kinetics but misses the phase separation aspect. Option D describes a possible outcome but is too specific to eutectic systems and doesn't capture the general phenomenon.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2181, "question": "What is the difference between fibrous structure and texture?", "answer": "Fibrous structure is formed by grains, impurities, second phases, defects, etc., being elongated into fibrous shapes along the main deformation direction of the metal; whereas texture refers to the certain orientation relationship among grains after cold working, where certain crystal planes or directions are parallel to each other and all parallel to an external reference direction of the component.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述两个概念之间的区别，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对纤维结构和织构这两个基本概念的定义和区别的记忆和理解，不涉及复杂的应用或分析过程。 | 难度: 在选择题中属于较高难度，题目要求考生不仅要理解\"纤维结构\"和\"织构\"这两个专业术语的定义，还需要能够区分和比较这两个概念的具体特征和形成机制。正确选项包含了多个专业知识点（如晶粒变形、杂质分布、晶体取向关系等），需要考生对这些概念有较深入的理解才能准确作答。此外，题目涉及金属材料科学中较为复杂的微观结构概念体系，在选择题型内属于需要综合分析能力的高难度题目。", "convertible": true, "correct_option": "Fibrous structure is formed by grains, impurities, second phases, defects, etc., being elongated into fibrous shapes along the main deformation direction of the metal; whereas texture refers to the certain orientation relationship among grains after cold working, where certain crystal planes or directions are parallel to each other and all parallel to an external reference direction of the component.", "choice_question": "What is the difference between fibrous structure and texture?", "conversion_reason": "The answer is a standard definition that can be presented as one of the options in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fibrous structure involves physical elongation of microstructural features, while texture describes crystallographic orientation relationships", "B": "Both terms describe the same phenomenon but are used in different material systems", "C": "Fibrous structure refers to atomic-scale defects, while texture describes grain boundary arrangements", "D": "Texture is a 2D surface characteristic, while fibrous structure is a 3D bulk property" }, "correct_answer": "A", "explanation": "Correct answer A precisely distinguishes the physical elongation aspect of fibrous structure versus the crystallographic orientation aspect of texture. Option B exploits the cognitive bias of assuming synonymous technical terms. Option C creates confusion between microstructural and atomic-scale features. Option D traps those who incorrectly associate texture with surface characteristics rather than bulk crystallography.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 310, "question": "Why is the ΔG* of a cube greater than that of a sphere?", "answer": "When forming nuclei of the same volume, a³ = (4/3)πr³ ⇒ a > r. The surface area of a cube 6a² > the surface area of a sphere 4πr², therefore ΔG*cube > ΔG*sphere", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么立方体的ΔG*大于球体的ΔG*，答案通过文字解释和公式应用进行了论述，没有涉及选项选择、对错判断或具体数值计算。 | 知识层次: 题目需要理解核化自由能（ΔG*）与几何形状的关系，涉及体积和表面积的计算比较，属于多步计算和概念关联的中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及ΔG*的计算和几何形状对表面能的影响，要求考生能够将体积与表面积的关系联系起来，并进行多步计算和综合分析。虽然题目提供了正确选项，但仍需要一定的知识掌握和逻辑推理能力来理解为什么立方体的ΔG*大于球体。", "convertible": true, "correct_option": "When forming nuclei of the same volume, a³ = (4/3)πr³ ⇒ a > r. The surface area of a cube 6a² > the surface area of a sphere 4πr², therefore ΔG*cube > ΔG*sphere", "choice_question": "Why is the ΔG* of a cube greater than that of a sphere?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The cube has higher surface energy due to its larger surface area to volume ratio", "B": "The sphere's curvature allows more efficient atomic packing at the interface", "C": "Cubic nuclei require additional strain energy to maintain sharp edges", "D": "The sphere minimizes interfacial defects through isotropic growth" }, "correct_answer": "A", "explanation": "The correct answer is A because ΔG* depends on surface area, and for equal volumes, a cube has greater surface area than a sphere. Option B exploits intuition about atomic packing but is irrelevant to surface energy. Option C introduces a plausible-sounding strain energy factor that doesn't actually affect ΔG* calculations. Option D misdirects by invoking defect minimization which isn't part of classical nucleation theory.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1451, "question": "For an edge dislocation line, what is the relationship between its Burgers vector and the dislocation line?", "answer": "Perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释刃位错线的Burgers矢量与位错线之间的关系，答案需要文字描述（\"Perpendicular\"），属于简答题类型。 | 知识层次: 题目考查对位错基本概念的记忆和理解，特别是刃位错的Burgers矢量与位错线方向的关系，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即刃位错的柏氏矢量与位错线的关系。不需要解释或分析，只需直接回忆定义即可选出正确答案\"Perpendicular\"。属于最基本的概念记忆题。", "convertible": true, "correct_option": "Perpendicular", "choice_question": "For an edge dislocation line, what is the relationship between its Burgers vector and the dislocation line?", "conversion_reason": "The answer is a standard term (Perpendicular), which can be presented as a single correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Perpendicular", "B": "Parallel", "C": "At a 45-degree angle", "D": "The Burgers vector magnitude determines the angle" }, "correct_answer": "A", "explanation": "The correct answer is A because for an edge dislocation, the Burgers vector is always perpendicular to the dislocation line by definition. Option B is a common mistake as it describes screw dislocations. Option C exploits the visual similarity between mixed dislocations and pure edge dislocations. Option D is a sophisticated trap that misapplies the concept of Burgers vector magnitude dependence in other contexts.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2618, "question": "What are the characteristics of physical bonds (van der Waals forces)?", "answer": "Physical bonds: secondary bonds, also known as van der Waals forces.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释物理键（范德华力）的特性，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查物理键（范德华力）的基本特征和定义，属于基础概念的记忆和理解范畴 | 难度: 在选择题型中，该题目仅要求识别物理键（范德华力）的基本定义和分类，属于基础概念记忆层次。题目仅需选择正确选项，无需复杂分析或概念比较，解题步骤简单直接。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "secondary bonds, also known as van der Waals forces", "choice_question": "Which of the following are the characteristics of physical bonds (van der Waals forces)?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Secondary bonds with bond energies typically below 0.5 eV", "B": "Directional covalent interactions with bond energies around 2-5 eV", "C": "Primary bonds exhibiting temperature-dependent strength", "D": "Ionic bonds with complete electron transfer" }, "correct_answer": "A", "explanation": "The correct answer is A because van der Waals forces are indeed secondary bonds with typical bond energies below 0.5 eV. Option B is incorrect as it describes covalent bonds, which are primary bonds. Option C is a trap as it mixes the correct concept of temperature dependence (true for van der Waals) with primary bonds (false). Option D describes ionic bonding, another primary bond type. The difficulty comes from mixing correct partial characteristics (like temperature dependence) with incorrect bond types.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2697, "question": "Calculate the theoretical packing density of α-Fe (given rFe=0.1241nm, a=0.286nm)", "answer": "Ktheoretical=8/3×π×rFe³/a³=8/3×π×(0.1241)³/(0.286)³=0.6844", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过具体计算得出的数值结果 | 知识层次: 题目要求应用基本公式进行数值计算，属于直接套用公式的简单应用，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算α-Fe的理论堆积密度，只需套用给定的公式和参数进行简单计算即可得出结果。不需要理解多个概念或进行复杂的分析，解题步骤直接且明确。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "0.6844", "choice_question": "What is the theoretical packing density of α-Fe (given rFe=0.1241nm, a=0.286nm)?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.6844", "B": "0.7405", "C": "0.6802", "D": "0.7241" }, "correct_answer": "A", "explanation": "The correct answer is A (0.6844) which is the theoretical packing density for a BCC structure (α-Fe). Option B (0.7405) is the packing density for FCC/HCP structures, exploiting the common confusion between BCC and FCC packing densities. Option C (0.6802) is close to the correct value but uses an incorrect atomic radius calculation, targeting calculation precision errors. Option D (0.7241) is a hybrid value between BCC and FCC, designed to trap those who might consider α-Fe as having an intermediate structure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2854, "question": "For an Al2O3 specimen with a square cross-section of side length 12mm in a three-point bending test, the distance between the two supports is 40mm. Given the material's fracture strength σfs=352.6 MPa, find the load at fracture Ff.", "answer": "Ff = (2 * σfs * b^3) / (3 * L) = (2 * 352.6 * 10^6 * (12 * 10^-3)^3) / (3 * 40 * 10^-3) = 10154.9 N", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解断裂载荷Ff，答案是一个具体的数值结果，解答过程涉及公式代入和单位转换，符合计算题的特征。 | 知识层次: 题目主要考查基本公式的应用和简单计算，涉及三点弯曲测试中的断裂强度公式直接套用，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解三点弯曲测试的基本原理和公式，但解题步骤相对直接，仅需套用给定的公式并进行简单的单位转换和计算。不需要多个公式的组合或复杂的分析，因此属于等级2难度。", "convertible": true, "correct_option": "10154.9 N", "choice_question": "For an Al2O3 specimen with a square cross-section of side length 12mm in a three-point bending test, the distance between the two supports is 40mm. Given the material's fracture strength σfs=352.6 MPa, the load at fracture Ff is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "10154.9 N", "B": "5077.4 N", "C": "20309.8 N", "D": "7608.6 N" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the three-point bending formula: Ff = (σfs * b * d^2) / (1.5 * L), where b=12mm, d=12mm, L=40mm. Option B is half the correct value, exploiting the common mistake of omitting the 1.5 factor. Option C doubles the correct value, targeting those who confuse three-point with four-point bending. Option D is derived from incorrectly using shear strength instead of fracture strength, appealing to material property confusion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1905, "question": "Glass phase separation", "answer": "3. Glass phase separation: A homogeneous glass phase may, within certain temperature and composition ranges, separate into two mutually insoluble or partially soluble glass phases that coexist. This phenomenon is called glass phase separation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Glass phase separation\"这一现象进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对玻璃相分离现象的基本定义和描述，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要考生理解\"玻璃相分离\"的定义和基本原理，但题目本身提供了完整的解释，考生只需识别和匹配正确选项即可。不需要进行复杂的概念比较或推导，属于概念解释和描述层面的考查。", "convertible": true, "correct_option": "A homogeneous glass phase may, within certain temperature and composition ranges, separate into two mutually insoluble or partially soluble glass phases that coexist. This phenomenon is called glass phase separation.", "choice_question": "Which of the following best describes glass phase separation?", "conversion_reason": "The answer provided is a standard definition of the term 'glass phase separation', which can be used as the correct option in a multiple-choice question. The question can be rephrased to ask for the best description of the term.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A homogeneous glass phase may, within certain temperature and composition ranges, separate into two mutually insoluble or partially soluble glass phases that coexist.", "B": "The process where crystalline phases nucleate and grow within an amorphous glass matrix during heat treatment.", "C": "The spontaneous formation of periodic density fluctuations in glass due to thermodynamic instability.", "D": "The irreversible chemical reaction between two different glass compositions when brought into contact at high temperatures." }, "correct_answer": "A", "explanation": "The correct answer A precisely describes glass phase separation as the demixing of a homogeneous glass into two distinct glassy phases. Option B describes crystallization, not phase separation. Option C refers to spinodal decomposition which is a specific mechanism of phase separation but not the general definition. Option D describes chemical reaction between glasses, not phase separation. The difficulty lies in distinguishing between these closely related but fundamentally different phenomena in glass science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4391, "question": "On the basis of microstructure, briefly explain why gray iron is brittle and weak in tension.", "answer": "Gray iron is weak and brittle in tension because the tips of the graphite flakes act as points of stress concentration.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释灰口铸铁在拉伸时脆性和强度低的原因，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求基于微观结构解释灰口铸铁的脆性和抗拉强度弱的原因，涉及应力集中机理的分析和微观组织与宏观性能的关联，需要综合运用材料科学知识进行推理和解释。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅要知道灰色铸铁在拉伸时表现脆弱的表面现象，还需要深入理解其微观结构（石墨片尖端）如何作为应力集中点导致材料性能下降的机理。这需要考生具备将微观结构与宏观性能联系起来的综合分析能力，以及对材料失效机理的深入理解。在选择题型中，这种需要结合多个知识点进行机理解释的题目属于较难的类型。", "convertible": true, "correct_option": "Gray iron is weak and brittle in tension because the tips of the graphite flakes act as points of stress concentration.", "choice_question": "Why is gray iron brittle and weak in tension based on its microstructure?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The graphite flakes create stress concentration points that initiate cracks under tension", "B": "The pearlite matrix has inherently low ductility due to its lamellar structure", "C": "The high carbon content reduces dislocation mobility in the ferrite phase", "D": "Graphite-matrix interface decohesion occurs before plastic deformation can begin" }, "correct_answer": "A", "explanation": "The correct answer is A because the sharp tips of graphite flakes act as stress concentrators that initiate cracks under tensile loading. Option B is a cognitive bias trap - while pearlite does have limited ductility, it's not the primary reason for gray iron's brittleness. Option C exploits material science confusion by mixing concepts from steel hardening. Option D is a professional intuition trap - while interface decohesion does occur, it's a secondary effect to the stress concentration mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 777, "question": "Briefly describe the conditions for forming continuous substitutional solid solutions", "answer": "The conditions for forming continuous substitutional solid solutions are: ionic size factor, the radius difference between the two substituting ions (r1-r2)/r1<15%; the two components must have exactly the same crystal structure type; continuous substitutional solid solutions can only form when the ionic valences are the same or when the total valence of composite substituting ions is equal; similar electronegativity and polarization properties", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述形成连续置换固溶体的条件，答案以文字解释和论述的形式呈现，没有涉及选择、判断或计算。 | 知识层次: 题目考查对形成连续置换固溶体条件的记忆和理解，属于基础概念和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求描述形成连续置换固溶体的条件，但正确选项已经提供了明确的要点（离子尺寸因素、晶体结构类型、离子价态、电负性和极化性质）。这些要点属于基础概念记忆层次，不需要复杂的分析或推理。然而，由于涉及多个条件的列举和记忆，相对于仅回答单一基本定义的题目（等级1），该题目需要更全面的概念解释和描述能力，因此属于等级2难度。", "convertible": true, "correct_option": "The conditions for forming continuous substitutional solid solutions are: ionic size factor, the radius difference between the two substituting ions (r1-r2)/r1<15%; the two components must have exactly the same crystal structure type; continuous substitutional solid solutions can only form when the ionic valences are the same or when the total valence of composite substituting ions is equal; similar electronegativity and polarization properties", "choice_question": "Which of the following describes the conditions for forming continuous substitutional solid solutions?", "conversion_reason": "The answer is a standard set of conditions that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The atomic radius difference must be less than 15%, crystal structures must be identical, and electronegativity difference must be below 0.4", "B": "The atomic radius difference must exceed 8%, crystal structures can differ if lattice parameters match, and valency must be identical", "C": "The atomic radius difference must be less than 8%, crystal structures must be similar but not identical, and valency difference must be compensated by vacancies", "D": "The atomic radius difference must be less than 12%, crystal structures must be identical, and valency must be identical or charge-balanced" }, "correct_answer": "A", "explanation": "Correct answer A combines all necessary conditions: size factor (<15%), identical crystal structure, and similar electronegativity. Option B traps by allowing different crystal structures and incorrect size threshold. Option C uses a tempting but incorrect 8% radius limit and allows non-identical structures. Option D sets a plausible but incorrect 12% radius threshold and over-simplifies valence requirements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2927, "question": "The packing density of a simple cubic crystal is (A) $100\\\\%$ (B) $65\\\\%$ (C) $52\\\\%$ (D) $58\\\\%$", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(A)、(B)、(C)、(D)中选择正确答案 | 知识层次: 题目考查简单立方晶体堆积密度的基本概念记忆，属于晶体结构的基础知识，无需复杂计算或分析。 | 难度: 在选择题中属于简单难度，仅需记忆简单立方晶体的堆积密度数值即可作答，无需理解或分析复杂概念。", "convertible": true, "correct_option": "C", "choice_question": "The packing density of a simple cubic crystal is:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications needed to the question itself.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dislocation density in annealed copper is typically 10^6 cm^-2", "B": "The dislocation density in cold-worked aluminum is typically 10^8 cm^-2", "C": "The dislocation density in single crystal silicon is typically 10^10 cm^-2", "D": "The dislocation density in heavily deformed steel is typically 10^12 cm^-2" }, "correct_answer": "D", "explanation": "Correct answer D reflects the upper range of dislocation densities in heavily deformed metals. The traps are: A) uses correct value but wrong material (annealed copper should be 10^4-10^6), B) underestimates cold-worked metals, C) exploits AI's tendency to overestimate defect density in semiconductors (actual is 10^3-10^4 for single crystal Si). All options use plausible but contextually wrong values from different material classes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4733, "question": "A sheet of steel 5.0-mm thick has nitrogen atmospheres on both sides at 900^{\\circ} C and is permitted to achieve a steady-state diffusion condition. The diffusion coefficient for nitrogen in steel at this temperature is 1.85 × 10^{-10}{m}^{2} / s, and the diffusion flux is found to be 1.0 × 10^{-7} kg / m^{2}·s. Also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 2kg / m^{3}. How far into the sheet from this high-pressure side will the concentration be 0.5kg / m^{3} ? Assume a linear concentration profile.", "answer": "the concentration will be 0.5 \\mathrm{kg/m}^{3} at a distance of 2.78 mm from the high-pressure side.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用（如菲克第一定律）来求解氮浓度在钢板中的分布距离，答案是一个具体的数值结果（2.78 mm），符合计算题的特征。 | 知识层次: 题目涉及稳态扩散条件下的菲克第一定律应用，需要多步计算（包括浓度梯度计算和距离求解），并理解线性浓度分布的概念。虽然不涉及复杂的机理分析或创新设计，但需要综合运用扩散系数、扩散通量和浓度梯度等概念进行数值计算。 | 难度: 在选择题中属于中等难度，需要理解扩散系数、扩散通量、浓度梯度等概念，并进行多步计算和综合分析。题目要求考生能够应用菲克第一定律，建立线性浓度分布模型，并通过代数运算求解距离。虽然计算步骤较多，但在选择题型中，正确选项的存在降低了部分难度，因此属于等级3。", "convertible": true, "correct_option": "2.78 mm", "choice_question": "A sheet of steel 5.0-mm thick has nitrogen atmospheres on both sides at 900°C and is permitted to achieve a steady-state diffusion condition. The diffusion coefficient for nitrogen in steel at this temperature is 1.85 × 10^{-10} m²/s, and the diffusion flux is found to be 1.0 × 10^{-7} kg/m²·s. Also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 2 kg/m³. How far into the sheet from this high-pressure side will the concentration be 0.5 kg/m³? Assume a linear concentration profile.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.78 mm", "B": "1.39 mm", "C": "3.70 mm", "D": "4.63 mm" }, "correct_answer": "A", "explanation": "正确答案A是通过Fick第一定律计算得出：J = -D(dC/dx)，其中dC/dx = (0.5-2)/x = -1.5/x。代入J=1.0×10^{-7}和D=1.85×10^{-10}，解得x=2.78mm。干扰项B是正确答案的一半，利用了线性关系中常见的1/2直觉陷阱。干扰项C是正确答案的4/3倍，利用了扩散距离与浓度比的非线性直觉错误。干扰项D是正确答案的5/3倍，设计为看起来像是考虑了厚度5mm的简单比例关系。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1971, "question": "Nickel has a face-centered cubic structure with an atomic radius of r_Ni=0.1246 nm. Determine how many atoms are present in 1 mm^2 on the (100) plane of nickel.", "answer": "6.1×10^13 atoms/mm^2", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及原子半径、晶面密度等材料科学参数的计算，最终要求得出具体的数值结果（6.1×10^13 atoms/mm^2）。 | 知识层次: 题目需要理解面心立方结构在(100)面上的原子排列方式，计算单位面积上的原子数，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解面心立方结构、(100)晶面的原子排布、原子半径与晶格参数的关系等概念，并进行多步计算（包括晶格参数计算、面密度计算、单位换算等）。虽然题目给出了正确选项，但解题过程涉及多个知识点的综合应用和计算步骤，比单纯的概念识别或单步计算题目更复杂。", "convertible": true, "correct_option": "6.1×10^13 atoms/mm^2", "choice_question": "Nickel has a face-centered cubic structure with an atomic radius of r_Ni=0.1246 nm. How many atoms are present in 1 mm^2 on the (100) plane of nickel?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.1×10^13 atoms/mm^2", "B": "1.2×10^14 atoms/mm^2", "C": "3.0×10^13 atoms/mm^2", "D": "8.5×10^13 atoms/mm^2" }, "correct_answer": "A", "explanation": "正确答案A是通过计算(100)面上原子密度得到的：首先计算晶格常数a=4r/√2=0.3516 nm，然后(100)面原子密度为2/a^2=1.62×10^19 atoms/m^2=1.62×10^13 atoms/mm^2。但镍是FCC结构，(100)面实际有2层原子，因此需要乘以√2得到6.1×10^13 atoms/mm^2。干扰项B错误地将原子半径直接作为原子间距计算；C忽略了FCC结构的层间原子；D错误地使用了体心立方结构的计算方法。这些干扰项利用了材料晶体结构计算中常见的认知偏差和直觉错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 473, "question": "1. How many independent slip systems must be activated for plastic deformation in polycrystalline materials?", "answer": "5", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的数值（5），但没有提供选项供选择，属于需要直接回答的简答题形式。 | 知识层次: 题目考查的是关于多晶材料塑性变形所需独立滑移系统数量的基本概念记忆，属于材料科学中关于塑性变形的基础知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即\"多晶材料塑性变形需要激活多少个独立滑移系统\"这一具体数值的记忆。题目不涉及概念解释或复杂体系分析，属于最基础的定义简答类型，符合等级1的难度标准。", "convertible": true, "correct_option": "5", "choice_question": "How many independent slip systems must be activated for plastic deformation in polycrystalline materials?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项D", "B": "5", "C": "选项B", "D": "选项C" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 625, "question": "Columnar crystals and equiaxed crystals", "answer": "Columnar crystals and equiaxed crystals: During the crystallization process of metal crystals, the elongated grains that preferentially grow along the heat dissipation direction are called columnar crystals, while if the grains grow without a preferred direction and the growth rates in all directions are roughly equal, the resulting grains are called equiaxed crystals.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Columnar crystals and equiaxed crystals\"进行文字解释和论述，答案提供了详细的定义和特征描述，符合简答题的特点。 | 知识层次: 题目考查柱状晶和等轴晶的基本定义和形成过程，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并区分两种晶体生长方式（柱状晶和等轴晶）的定义及其形成条件。这比单纯记忆一个定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "During the crystallization process of metal crystals, the elongated grains that preferentially grow along the heat dissipation direction are called columnar crystals, while if the grains grow without a preferred direction and the growth rates in all directions are roughly equal, the resulting grains are called equiaxed crystals.", "choice_question": "Which of the following correctly describes columnar crystals and equiaxed crystals?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting the definition as the correct option among other plausible but incorrect definitions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Columnar crystals form due to directional heat flow during solidification, while equiaxed crystals result from uniform nucleation conditions", "B": "Columnar crystals exhibit isotropic mechanical properties, whereas equiaxed crystals show anisotropic behavior", "C": "Equiaxed crystals grow preferentially along the temperature gradient, while columnar crystals form in undercooled melts", "D": "Both crystal types always coexist in equal proportions regardless of cooling rate" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the fundamental difference in formation mechanisms. Option B reverses the expected mechanical behavior (columnar crystals are actually anisotropic). Option C swaps the definitions of the two crystal types. Option D is incorrect as their proportions vary significantly with cooling conditions. The difficulty lies in the subtle reversal of properties in options B and C, which may trap AI systems relying on pattern matching rather than deep metallurgical knowledge.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 961, "question": "Briefly describe the Bravais lattice", "answer": "A lattice that considers not only the shape of the unit cell but also the positions of the lattice points (or: considers not only rotational symmetry but also translational symmetry, forming all lattice points after centering).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述Bravais lattice的概念，答案是一段文字解释，符合简答题的特征 | 知识层次: 题目考查对Bravais晶格这一基本概念的定义和特征的理解，属于基础概念记忆范畴，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求对Bravais晶格的基本定义进行简单记忆和复述，属于最基础的概念性知识。正确选项直接给出了定义性描述，不需要进行任何概念比较或复杂推理，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "A lattice that considers not only the shape of the unit cell but also the positions of the lattice points (or: considers not only rotational symmetry but also translational symmetry, forming all lattice points after centering).", "choice_question": "Which of the following best describes the Bravais lattice?", "conversion_reason": "The answer is a standard definition of the Bravais lattice, which can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A lattice that considers not only the shape of the unit cell but also the positions of the lattice points", "B": "A lattice defined solely by the symmetry operations that leave the crystal invariant", "C": "A lattice formed by the smallest repeating unit that captures all symmetry elements", "D": "A lattice that can be fully described by its primitive vectors without considering centering" }, "correct_answer": "A", "explanation": "The Bravais lattice specifically accounts for both unit cell shape and lattice point positions (including centering), making A correct. Option B describes the space group concept, not Bravais lattices. Option C is incorrect because it confuses Bravais lattices with the primitive cell concept. Option D is a common misconception that ignores the critical role of centering in Bravais lattice classification.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1016, "question": "For cold-rolled pure copper sheets, what heat treatment should be performed if further cold rolling to reduce thickness is required?", "answer": "To continue cold deformation, high-temperature annealing should be conducted to induce recrystallization and soften the microstructure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释应采取的热处理措施，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及对冷轧纯铜板材的热处理工艺选择，需要理解冷变形后的材料状态以及再结晶退火的作用，属于将基本原理应用于具体工艺场景的中等应用层次。虽然不涉及复杂计算，但需要综合分析材料状态与热处理目的之间的关系。 | 难度: 在选择题中属于中等难度，需要理解冷轧纯铜板材的加工硬化现象、再结晶退火的作用以及后续冷轧工艺要求之间的关联。题目要求考生综合应用材料加工和热处理知识，判断在特定工艺条件下应采取的热处理措施，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "High-temperature annealing should be conducted to induce recrystallization and soften the microstructure.", "choice_question": "For cold-rolled pure copper sheets, what heat treatment should be performed if further cold rolling to reduce thickness is required?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by providing the correct option and distractor options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High-temperature annealing to induce recrystallization", "B": "Low-temperature stress relief annealing at 200°C", "C": "Solution treatment followed by quenching", "D": "Precipitation hardening at 450°C" }, "correct_answer": "A", "explanation": "High-temperature annealing is required to induce recrystallization and soften cold-worked copper for further processing. Option B is a cognitive bias trap - stress relief is insufficient for recrystallization. Option C exploits confusion with aluminum alloy treatments. Option D is a professional intuition trap - precipitation hardening doesn't apply to pure copper.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1664, "question": "The three crystal zones of an ingot refer to the fine crystal zone near the inner wall of the mold, _ (10) __, and the equiaxed coarse crystal zone at the center of the ingot", "answer": "(10) columnar crystal zone growing perpendicular to the mold wall", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（columnar crystal zone growing perpendicular to the mold wall）来补全句子，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对铸锭三个晶区的基本概念的记忆和理解，特别是柱状晶区的定义和位置 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目要求考生记忆并识别铸锭的三个晶区名称，正确选项直接给出了其中一个晶区的定义描述，无需进行复杂的概念分析或比较。考生只需掌握基础概念记忆即可正确作答，符合等级1的难度标准。", "convertible": true, "correct_option": "columnar crystal zone growing perpendicular to the mold wall", "choice_question": "The three crystal zones of an ingot refer to the fine crystal zone near the inner wall of the mold, ______, and the equiaxed coarse crystal zone at the center of the ingot.", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "columnar crystal zone growing perpendicular to the mold wall", "B": "dendritic crystal zone parallel to the heat flow direction", "C": "transition zone with mixed fine and columnar crystals", "D": "single crystal region formed by directional solidification" }, "correct_answer": "A", "explanation": "The correct answer is A because the three classical zones in ingot solidification are: 1) chill zone (fine crystals near mold wall), 2) columnar zone (perpendicular growth), and 3) equiaxed zone (center). Option B is a cognitive bias trap - while dendrites exist, they're not a distinct zone. Option C exploits the common misconception about transition zones. Option D is an intuition trap using a real but irrelevant single crystal concept.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2504, "question": "What is the reason for the difference in property changes between short-period elements and long-period elements?", "answer": "This is because the number of subshell electrons in the long-period transition elements also affects the properties of the elements.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释元素性质变化的原因，答案提供了文字解释和论述，符合简答题的特征 | 知识层次: 题目要求解释短周期元素和长周期元素性质差异的原因，涉及对元素周期表中不同周期元素电子排布和性质变化的深入理解，需要综合运用原子结构和周期律的知识进行推理分析，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "This is because the number of subshell electrons in the long-period transition elements also affects the properties of the elements.", "choice_question": "What is the reason for the difference in property changes between short-period elements and long-period elements?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The presence of d-block elements introduces additional electron shielding effects", "B": "Long-period elements exhibit stronger metallic bonding due to increased nuclear charge", "C": "Relativistic effects become significant in heavier elements altering orbital shapes", "D": "The lanthanide contraction causes unexpected periodicity in transition metals" }, "correct_answer": "A", "explanation": "The correct answer is A because the additional electron shielding from d-electrons in long-period elements fundamentally changes their properties compared to short-period elements. Option B is a cognitive bias trap - while nuclear charge increases, metallic bonding isn't the primary reason for property differences. Option C exploits professional intuition by citing real but irrelevant relativistic effects. Option D is a multi-level trap using the valid concept of lanthanide contraction but misapplying it to general periodicity differences.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 209, "question": "Many properties of clay are related to the types of adsorbed cations. Indicate the variation trend in slurry stability when clay adsorbs the following different cations (use arrows to show: small—large) H+ Al3+ Ba2+ Sr2+ Ca2+ Mg2+ NH4+ K+ Na+ Li+", "answer": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求用箭头表示不同阳离子吸附时泥浆稳定性的变化趋势，需要根据材料科学知识进行排序和解释，属于简答题类型。答案形式为一系列符号排列，而非选择或判断。 | 知识层次: 题目要求考生理解不同阳离子对黏土浆体稳定性的影响，并能够根据阳离子的性质（如电荷、离子半径等）进行排序。这需要考生不仅记住阳离子的基本性质，还要能够将这些性质与黏土浆体稳定性的变化趋势关联起来，进行综合分析。虽然不涉及复杂的计算或机理解释，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题型中属于较高难度，需要考生掌握黏土吸附阳离子的相关知识，并能综合分析不同阳离子对黏土浆体稳定性的影响趋势。题目要求考生对多个阳离子的吸附能力进行排序，涉及多步计算和概念关联，需要较强的综合分析能力。", "convertible": true, "correct_option": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "choice_question": "When clay adsorbs different cations, what is the variation trend in slurry stability (from small to large)?", "conversion_reason": "The answer is a specific ordered sequence, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "B": "Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+ < H+", "C": "Al3+ < H+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "D": "H+ < Al3+ < Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+" }, "correct_answer": "A", "explanation": "The correct answer is A because slurry stability increases with decreasing cation hydration energy and increasing ionic radius. This creates the specific sequence where H+ (smallest hydration shell) is least stable, while Li+ (largest hydrated radius among alkali metals) provides maximum stability. Option B reverses the trend, exploiting the common misconception that higher charge always increases stability. Option C incorrectly places Al3+ before H+, targeting confusion about trivalent cation behavior. Option D mixes up the sequence of monovalent and divalent cations, capitalizing on the complexity of hydration effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 68, "question": "In silicate crystals, why can Al3+ partially replace Si4+ in the silicon-oxygen framework?", "answer": "Al3+ can form [AlO4]5- with O2-. Al3+ and Si4+ are in the second period and have similar properties, making it easy for Al3+ to enter the silicate crystal structure and undergo isomorphous substitution with Si4+. Due to compliance with Pauling's rules, only partial substitution is possible.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Al3+可以部分替代Si4+的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要解释Al3+在硅酸盐晶体中部分替代Si4+的原因，涉及[AlO4]5-的形成、Al3+和Si4+的性质相似性、同晶替代以及Pauling规则的遵守。这需要综合运用晶体化学、离子替代机制和结构规则等多方面知识，并进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Al3+ can form [AlO4]5- with O2-. Al3+ and Si4+ are in the second period and have similar properties, making it easy for Al3+ to enter the silicate crystal structure and undergo isomorphous substitution with Si4+. Due to compliance with Pauling's rules, only partial substitution is possible.", "choice_question": "Why can Al3+ partially replace Si4+ in the silicon-oxygen framework in silicate crystals?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Al3+ and Si4+ have identical ionic radii allowing direct substitution", "B": "The [AlO4]5- tetrahedron has the same charge as [SiO4]4- units", "C": "Al3+ forms [AlO4]5- tetrahedra with oxygen and follows Pauling's rules for partial substitution", "D": "Aluminum and silicon have identical electronegativity values enabling complete substitution" }, "correct_answer": "C", "explanation": "Correct answer C combines three critical aspects: 1) Formation of [AlO4]5- tetrahedra, 2) Structural compatibility with silicate framework, and 3) Pauling's rules limitation. Option A is wrong because while radii are similar, they're not identical (Al3+ is slightly larger). Option B contains a charge calculation error ([AlO4]5- vs [SiO4]4-). Option D is false as their electronegativities differ (Al 1.61 vs Si 1.90). Advanced AIs might select B due to charge miscalculation or D from overgeneralizing periodic trends.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1189, "question": "What is the main difference between the first type and the second type of temper brittleness?", "answer": "The first type of temper brittleness is irreversible, while the second type is reversible. The first type of temper brittleness is caused by the precipitation of discontinuous thin-shell carbides along the interfaces of martensite laths or plates during martensite decomposition. The second type of temper brittleness is caused by the segregation of impurity elements such as Sb, Sn, P, and As to the original austenite grain boundaries during tempering.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释两种回火脆性的主要区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释两种回火脆性的主要区别，涉及不可逆与可逆性的对比、微观机理分析（碳化物析出和杂质元素偏聚）、以及材料相变过程的综合理解。这需要深入掌握材料科学中的相变理论和缺陷机制，属于对复杂现象的机理分析和综合运用。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The first type of temper brittleness is irreversible, while the second type is reversible.", "choice_question": "What is the main difference between the first type and the second type of temper brittleness?", "conversion_reason": "The answer is a clear and concise statement that can be used as a correct option in a multiple-choice question. The question can be reformatted to present this statement along with plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The first type occurs during slow cooling through 400-600°C while the second type occurs during rapid quenching", "B": "The first type affects impact toughness while the second type affects tensile strength", "C": "The first type is reversible through heat treatment while the second type is permanent", "D": "The first type is caused by phosphorus segregation while the second type involves molybdenum depletion" }, "correct_answer": "A", "explanation": "The correct answer is A because the key difference lies in the temperature range and cooling rate sensitivity. Option B is incorrect as both types primarily affect impact toughness. Option C reverses the actual reversibility characteristics. Option D describes contributing factors rather than the fundamental difference. Advanced AI systems might select C due to its plausible-sounding reversal of properties, or D because it mentions real metallurgical mechanisms, but both miss the core distinction in formation conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2299, "question": "Briefly describe the relationship between the size of composite material specimens and their strength.", "answer": "The larger the composite material specimen, the higher the probability of defects, and the lower the strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述复合材料试样尺寸与其强度之间的关系，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对复合材料尺寸与强度关系的基本概念的理解，属于基本原理的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解复合材料尺寸与强度之间的关系，并能够解释其中的基本原理（缺陷概率增加导致强度降低）。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。", "convertible": true, "correct_option": "The larger the composite material specimen, the higher the probability of defects, and the lower the strength.", "choice_question": "Which of the following best describes the relationship between the size of composite material specimens and their strength?", "conversion_reason": "The answer is a standard description that can be converted into a correct option for a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The larger the composite material specimen, the higher the probability of defects, and the lower the strength", "B": "Larger specimens exhibit higher strength due to increased cross-sectional area and better load distribution", "C": "Size has no effect on strength as long as the fiber-matrix ratio remains constant", "D": "Smaller specimens show lower strength due to edge effects and incomplete stress transfer" }, "correct_answer": "A", "explanation": "The correct answer is A because larger composite specimens inherently have a higher probability of containing critical defects (like voids or fiber misalignment) that act as stress concentrators, leading to reduced strength. Option B is a cognitive bias trap, appealing to the intuitive but incorrect notion that bigger means stronger. Option C exploits material science confusion by suggesting a constant fiber-matrix ratio guarantees size independence, ignoring defect statistics. Option D is a professional intuition trap, reversing the actual edge effect phenomenon where smaller specimens often show higher apparent strength.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 900, "question": "Term explanation: Twinning", "answer": "Twinning refers to the shear process in which a crystal undergoes deformation by forming twins under stress.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对术语\"Twinning\"进行解释，需要提供文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对\"Twinning\"这一晶体变形过程的基本定义和概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，此题仅要求对\"Twinning\"这一基础概念进行简单的定义记忆和识别。正确选项直接给出了明确的定义描述，不需要进行概念间的比较或复杂推理，属于最基本的概念记忆层次。", "convertible": true, "correct_option": "Twinning refers to the shear process in which a crystal undergoes deformation by forming twins under stress.", "choice_question": "Which of the following best defines 'Twinning'?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Twinning refers to the shear process in which a crystal undergoes deformation by forming twins under stress", "B": "Twinning is the phenomenon where two crystals grow symmetrically from a common nucleation point", "C": "Twinning describes the alignment of crystal lattices during solidification to minimize interfacial energy", "D": "Twinning occurs when dislocations rearrange to form mirror-image crystallographic planes" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines twinning as a deformation mechanism involving shear-induced mirror-image crystallographic orientations. Option B exploits confusion with crystal growth phenomena, Option C targets misunderstanding of solidification processes, and Option D creates a dislocation theory trap by describing a plausible but incorrect mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1124, "question": "Use the phase rule to explain why a ternary alloy can exhibit four-phase equilibrium", "answer": "The phase rule formula is f=c-p+1, where f, c, p represent degrees of freedom, number of components, and number of phases, respectively. For a ternary alloy, when f reaches its minimum value of 0, the number of phases p is 4, indicating that four-phase equilibrium can occur. However, at this point, the degrees of freedom f is 0, meaning the compositions of all phases and the temperature are fixed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求使用相律解释三元合金可以呈现四相平衡的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求应用相律公式解释三元合金的四相平衡现象，涉及多步计算和概念关联，需要理解相律的基本原理并能够将其应用于具体情境。虽然不涉及复杂的推理分析或创新应用，但需要一定的综合分析能力来理解自由度、组分和相数之间的关系。 | 难度: 在选择题中属于较高难度，需要理解相律公式并正确代入数值进行计算，同时需要解释自由度为零时的物理意义。题目涉及多步计算和概念关联，要求考生能够综合分析相律在多元合金中的应用。虽然题目提供了正确选项，但理解其背后的原理需要较深的知识掌握和逻辑推理能力。", "convertible": true, "correct_option": "The phase rule formula is f=c-p+1, where f, c, p represent degrees of freedom, number of components, and number of phases, respectively. For a ternary alloy, when f reaches its minimum value of 0, the number of phases p is 4, indicating that four-phase equilibrium can occur. However, at this point, the degrees of freedom f is 0, meaning the compositions of all phases and the temperature are fixed.", "choice_question": "Use the phase rule to explain why a ternary alloy can exhibit four-phase equilibrium:", "conversion_reason": "The answer is a standard explanation involving the phase rule and can be presented as a correct option among other plausible but incorrect explanations.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phase rule allows for four-phase equilibrium when the degrees of freedom (f) reach zero in a ternary system (c=3), satisfying f=c-p+2 with p=4", "B": "Ternary alloys can exhibit four-phase equilibrium because the Gibbs phase rule is modified to f=c-p+3 for metallic systems", "C": "Four-phase equilibrium occurs when the chemical potential gradients balance out, independent of the phase rule constraints", "D": "This is only possible under non-equilibrium conditions where the phase rule doesn't apply" }, "correct_answer": "A", "explanation": "The correct answer A uses the proper phase rule formulation (f=c-p+2) showing how p=4 when f=0 for c=3. Option B falsely claims a modified phase rule for metals. Option C introduces a plausible-sounding but irrelevant concept of chemical potential balance. Option D exploits the common misconception that phase rules only apply to equilibrium conditions, creating a tempting but incorrect escape route.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4467, "question": "From a molecular perspective, briefly explain the mechanism by which clay minerals become hydroplastic when water is added.", "answer": "Clays become hydroplastic when water is added because the water molecules occupy regions between the layered molecular sheets; these water molecules essentially eliminate the secondary molecular bonds between adjacent sheets, and also form a thin film around the clay particles. The net result is that the clay particles are relatively free to move past one another, which is manifested as the hydroplasticity phenomenon.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求从分子角度简要解释黏土矿物在加水后变得具有水塑性的机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求从分子层面解释黏土矿物加水后产生水塑性的机理，涉及分子间作用力、水分子在层状结构中的行为以及宏观性能变化的关联，需要综合运用材料科学、化学等多学科知识进行推理分析，思维深度要求较高。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Clays become hydroplastic when water is added because the water molecules occupy regions between the layered molecular sheets; these water molecules essentially eliminate the secondary molecular bonds between adjacent sheets, and also form a thin film around the clay particles. The net result is that the clay particles are relatively free to move past one another, which is manifested as the hydroplasticity phenomenon.", "choice_question": "From a molecular perspective, which of the following best explains the mechanism by which clay minerals become hydroplastic when water is added?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best explanation among given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Water molecules form hydrogen bonds with the clay's surface hydroxyl groups, creating a lubricating layer that allows sheet slippage", "B": "Intercalated water molecules disrupt van der Waals forces between clay sheets while maintaining primary covalent bonds, enabling plastic deformation", "C": "Hydration of exchangeable cations increases ionic repulsion between clay layers, overcoming their electrostatic attraction", "D": "Capillary action draws water into clay's nanopores, reducing internal friction through hydrodynamic lubrication" }, "correct_answer": "B", "explanation": "Correct answer B precisely describes the dual mechanism of secondary bond disruption while maintaining structural integrity. Option A incorrectly focuses solely on surface effects. Option C overemphasizes cation hydration while neglecting the critical role of interlayer water. Option D mistakenly applies macroscopic fluid mechanics to nanoscale phenomena. These distractors exploit common misconceptions about clay plasticity mechanisms at different length scales.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3411, "question": "Explain the meaning of the steel grade 08F", "answer": "08F is a plain carbon structural steel, wc=0.08% rimmed steel", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释钢号08F的含义，答案提供了文字解释和论述，符合简答题的特征 | 知识层次: 题目考查对钢材牌号基本概念的记忆和理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目仅要求考生记忆并识别08F钢的基本定义和成分（wc=0.08%的沸腾钢），属于最基础的概念记忆层次，无需解释或推理过程，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "08F is a plain carbon structural steel, wc=0.08% rimmed steel", "choice_question": "Which of the following best describes the meaning of the steel grade 08F?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "08F is a plain carbon structural steel, wc=0.08% rimmed steel", "B": "08F denotes a stainless steel with 8% chromium content and free-machining properties", "C": "08F represents a high-strength low-alloy steel with 0.8% carbon and ferritic microstructure", "D": "08F indicates a tool steel with 0.08% vanadium and forged microstructure" }, "correct_answer": "A", "explanation": "The correct answer is A because 08F follows the Chinese GB standard naming convention where '08' indicates 0.08% carbon content and 'F' stands for rimmed steel. Option B is designed to exploit confusion between carbon steel and stainless steel grading systems. Option C uses a plausible-sounding HSLA steel description but with incorrect carbon percentage (0.8% instead of 0.08%). Option D creates a tool steel misconception by introducing vanadium content which doesn't exist in 08F steel.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4110, "question": "Which of aramid and metal fibers have higher strength-to-weight ratios?(a) Aramid fibers(b) Metal fibers", "answer": "Aramid fibers have higher strength-to-weight ratios than metal fibers.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从两个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对芳纶纤维和金属纤维强度重量比这一基本概念的简单记忆和比较，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即比较芳纶纤维和金属纤维的强度重量比。学生只需记住芳纶纤维具有更高的强度重量比这一事实即可选择正确答案，无需进行复杂的理解或分析。因此，该题目在选择题型内属于简单概念识别，直接记忆的难度等级。", "convertible": true, "correct_option": "Aramid fibers", "choice_question": "Which of aramid and metal fibers have higher strength-to-weight ratios?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly specifies the correct choice.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Aramid fibers due to their covalent bonding and aligned polymer chains", "B": "Metal fibers because metallic bonds inherently provide higher strength", "C": "They are equal since both achieve maximum theoretical bond strength", "D": "Depends on the specific metal alloy used" }, "correct_answer": "A", "explanation": "Aramid fibers have superior strength-to-weight ratios due to their covalent bonding and highly aligned molecular structure. Option B exploits the common misconception that metallic bonds are inherently stronger. Option C creates a false equivalence by ignoring fundamental material differences. Option D introduces a conditional trap that seems plausible but doesn't change the fundamental material property comparison.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4431, "question": "A hypothetical A X type of ceramic material is known to have a density of 2.65g / {cm}^{3} and a unit cell of cubic symmetry with a cell edge length of 0.43nm. The atomic weights of the A and X elements are 86.6 and 40.3g / mol, respectively. On the basis of this information, which of the following crystal structures is (are) possible for this material: rock salt, cesium chloride, or zinc blende? Justify your choice(s).", "answer": "the only possible crystal structure for this material is cesium chloride, which has one formula unit per unit cell.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求基于给定的材料信息，分析并判断可能的晶体结构类型，并给出合理的解释。这需要文字解释和论述，而不是简单的选择或计算。 | 知识层次: 题目需要综合运用密度计算、晶体结构分析、单位晶胞内原子数计算等知识，进行多步推理和综合分析，以确定可能的晶体结构类型。 | 难度: 在选择题型内，该题目属于较高难度，原因如下：", "convertible": true, "correct_option": "cesium chloride", "choice_question": "A hypothetical A X type of ceramic material is known to have a density of 2.65g/cm³ and a unit cell of cubic symmetry with a cell edge length of 0.43nm. The atomic weights of the A and X elements are 86.6 and 40.3g/mol, respectively. On the basis of this information, which of the following crystal structures is possible for this material?", "conversion_reason": "The original question asks to identify the possible crystal structure(s) from given options (rock salt, cesium chloride, or zinc blende), and the answer is a specific choice (cesium chloride). This can be directly converted to a multiple-choice question format by listing the options and identifying the correct one.", "perplexity": { "has_perplexity": false, "perplexity_type": "None", "perplexity_level": "None", "perplexity_reason": "The question provides all necessary information for a materials science graduate student to determine the possible crystal structure of the hypothetical AX type ceramic material. The density, unit cell edge length, atomic weights, and the types of crystal structures to consider (rock salt, cesium chloride, zinc blende) are all clearly stated.", "missing_info": "None" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cesium chloride (CsCl)", "B": "Rock salt (NaCl)", "C": "Zinc blende (ZnS)", "D": "Fluorite (CaF₂)" }, "correct_answer": "A", "explanation": "The correct answer is cesium chloride (CsCl) because the calculated density (2.65 g/cm³) and stoichiometry (1:1) match the given data when using the unit cell edge length (0.43 nm). The rock salt (B) structure is a common incorrect intuition due to its prevalence in ceramics, but it would require a different density for this composition. Zinc blende (C) is a trap for those confusing tetrahedral coordination with cubic symmetry. Fluorite (D) exploits the misconception that higher coordination numbers always lead to higher densities, which is invalid here due to the 1:1 stoichiometry constraint.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1672, "question": "Linear polymers can be reused and are called (19)__ plastics", "answer": "(19) thermoplastic", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（thermoplastic）来完成句子，属于需要提供简短文字答案的题型 | 知识层次: 题目考查对线性聚合物分类的基本概念记忆，仅需回答\"thermoplastic\"这一术语，属于基础概念的记忆性知识。 | 难度: 在选择题型中属于基础难度，仅需要记忆线性聚合物的基本分类术语\"thermoplastic\"这一单一知识点，无需解释或分析其他概念。题目直接考查基础定义记忆，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "thermoplastic", "choice_question": "Linear polymers can be reused and are called:", "conversion_reason": "The answer is a standard term (thermoplastic), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "thermoplastic", "B": "thermosetting", "C": "elastomeric", "D": "cross-linked" }, "correct_answer": "A", "explanation": "The correct answer is A (thermoplastic) because linear polymers can be melted and reshaped multiple times due to their non-crosslinked structure. B (thermosetting) is incorrect as these polymers form irreversible crosslinks upon curing, but the phrasing might trick AI into associating 'reused' with 'reprocessed'. C (elastomeric) is incorrect as it describes elastic behavior rather than recyclability, playing on the common confusion between mechanical properties and processability. D (cross-linked) is incorrect as it directly contradicts the linear polymer condition, but might be selected by AI due to overgeneralization from cases where crosslinking enables material reuse in different contexts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2263, "question": "What is the essence of aging?", "answer": "The essence of aging is the process of separating a new phase from a supersaturated solid solution, usually caused by temperature changes. The microstructure after aging consists of a matrix and precipitates. The matrix has the same crystal structure as the parent phase but differs in composition and lattice constants, while the precipitates can have different crystal structures and compositions from the parent phase. Due to variations in the properties, size, shape, and distribution of the precipitates in the microstructure, the performance of the alloy can change significantly.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对\"aging\"的本质进行解释和论述，答案提供了详细的文字描述和概念分析，符合简答题的特征。 | 知识层次: 题目要求解释时效的本质及其对合金性能的影响，涉及相变过程、微观结构变化以及性能变化的综合分析，需要深入理解时效的机理和多因素的相互作用。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解时效处理的基本概念，还需要掌握复杂的微观结构变化机理，包括基体和析出相的晶体结构差异、成分变化及其对合金性能的影响。这需要考生具备综合运用材料科学知识的能力，能够分析复杂现象并进行机理解释，远超简单的概念记忆或单一知识点应用。", "convertible": true, "correct_option": "The essence of aging is the process of separating a new phase from a supersaturated solid solution, usually caused by temperature changes. The microstructure after aging consists of a matrix and precipitates. The matrix has the same crystal structure as the parent phase but differs in composition and lattice constants, while the precipitates can have different crystal structures and compositions from the parent phase. Due to variations in the properties, size, shape, and distribution of the precipitates in the microstructure, the performance of the alloy can change significantly.", "choice_question": "Which of the following best describes the essence of aging?", "conversion_reason": "The answer is a standard and detailed explanation of the concept of aging, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best description of the essence of aging.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The process of separating a new phase from a supersaturated solid solution, leading to changes in microstructure and properties", "B": "The gradual loss of ductility in metals due to dislocation accumulation at grain boundaries", "C": "The spontaneous decomposition of intermetallic compounds into their constituent elements at elevated temperatures", "D": "The diffusion-controlled homogenization of composition gradients in solid solutions over time" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely describes the phase separation process that defines aging. Option B exploits cognitive bias by describing a real phenomenon (dislocation accumulation) that is unrelated to aging. Option C is a professional intuition trap, using terminology similar to aging but describing a different process. Option D is a multi-level verification trap, describing a diffusion process that occurs but is not the essence of aging.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1827, "question": "What type of diffusion problems is Fick's second law applicable to solve?", "answer": "Non-steady-state diffusion", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释Fick's second law适用的扩散问题类型，答案是一个简短的文字描述而非选择、判断或计算 | 知识层次: 题目考查对Fick第二定律适用范围的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅要求考生记忆并识别Fick's第二定律适用的扩散类型（非稳态扩散），属于基础概念的直接回忆。题目不涉及概念解释或复杂体系分析，仅需从选项中选出正确的基本定义，因此属于最简单的难度等级。", "convertible": true, "correct_option": "Non-steady-state diffusion", "choice_question": "What type of diffusion problems is Fick's second law applicable to solve?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Non-steady-state diffusion", "B": "Steady-state diffusion with time-dependent boundary conditions", "C": "Anisotropic diffusion in single crystals", "D": "Concentration-gradient independent diffusion" }, "correct_answer": "A", "explanation": "Fick's second law is specifically derived for non-steady-state diffusion where concentration changes with time. Option B is a high-level trap combining correct elements (time-dependence) but misapplying them to steady-state. Option C exploits the common confusion between diffusion types and material anisotropy. Option D targets the misconception that Fick's laws apply to all diffusion regimes, including non-concentration-gradient cases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 470, "question": "Perfect dislocation", "answer": "A dislocation whose Burgers vector equals a lattice vector is called a perfect dislocation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Perfect dislocation\"进行定义和解释，答案以文字形式给出，属于需要文字解释和论述的简答题类型 | 知识层次: 题目考查对完美位错（perfect dislocation）这一基本概念的定义记忆和理解，属于材料科学中位错理论的基础知识点，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅考察对\"perfect dislocation\"这一基础定义的记忆，无需解释或分析。正确选项直接给出了定义，属于最基础的概念记忆题，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "A dislocation whose Burgers vector equals a lattice vector is called a perfect dislocation.", "choice_question": "Which of the following describes a perfect dislocation?", "conversion_reason": "The original short answer question asks for a definition or description of 'perfect dislocation', which can be easily converted into a multiple-choice format by providing the correct definition as one option and plausible alternatives as other options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A dislocation whose Burgers vector equals a lattice vector", "B": "A dislocation with zero strain energy in its core region", "C": "A dislocation that perfectly follows the crystal symmetry planes", "D": "A dislocation whose Burgers vector magnitude equals the interatomic spacing" }, "correct_answer": "A", "explanation": "The correct answer is A because a perfect dislocation is specifically defined by having a Burgers vector that is equal to a lattice translation vector. Option B exploits the 'perfect' terminology to suggest zero strain energy, which is physically impossible. Option C plays on the geometric intuition of 'perfect alignment' with symmetry planes, which is irrelevant to the definition. Option D uses a common misconception about Burgers vector magnitude matching interatomic spacing, which is only true for simple cubic structures but not the general definition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 787, "question": "7. Lattice points", "answer": "Space lattice: A series of equivalent points identified in the crystal structure must be arranged in a periodic repetition in three-dimensional space. A series of geometric points arranged in a periodic repetition in three-dimensional space is called a space lattice.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Lattice points\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查空间点阵的基本定义和概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆和识别空间点阵的基本定义，属于基础概念记忆层次。题目直接给出了定义描述，无需进行复杂的概念解释或比较分析，因此属于最低难度等级。", "convertible": true, "correct_option": "Space lattice: A series of equivalent points identified in the crystal structure must be arranged in a periodic repetition in three-dimensional space. A series of geometric points arranged in a periodic repetition in three-dimensional space is called a space lattice.", "choice_question": "Which of the following correctly defines a space lattice?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct definition among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A series of geometric points arranged in a periodic repetition in three-dimensional space", "B": "The arrangement of atoms in a crystalline material with translational symmetry", "C": "A mathematical abstraction representing atomic positions without considering actual atoms", "D": "The smallest repeating unit that shows the full symmetry of the crystal structure" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a space lattice as a purely geometric concept of periodic points. Option B is a cognitive bias trap, confusing space lattice with crystal structure (which includes actual atoms). Option C is a professional intuition trap, incorrectly suggesting space lattices don't represent atomic positions. Option D is a multi-level verification trap, describing a unit cell rather than the infinite lattice.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1222, "question": "The higher the dislocation density, the larger the Burgers vector of the corresponding dislocation.", "answer": "~\\\\times~", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（对/错），答案以\"~\\\\times~\"形式给出，表示错误判断，这是典型的判断题特征 | 知识层次: 题目考查对位错密度和伯格斯矢量之间关系的基本概念的理解，属于基础概念记忆范畴。 | 难度: 该题目属于基础概念正误判断题，仅需记忆并判断位错密度与伯格斯矢量之间的基本关系是否正确。题目陈述简单直接，不需要复杂的理解或分析过程，在选择题型中属于最基本的难度等级。", "convertible": true, "correct_option": "~\\\\times~", "choice_question": "The higher the dislocation density, the larger the Burgers vector of the corresponding dislocation.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials exhibit a glass transition temperature when heated.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many amorphous materials do show a glass transition temperature, this is not universally true for all amorphous materials. Some amorphous materials may crystallize before reaching a glass transition temperature, or may decompose upon heating. The statement uses an absolute term 'all' which makes it incorrect. This tests understanding of both amorphous materials and thermal behavior concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4657, "question": "Titanium (Ti) has an HCP crystal structure and a density of 4.51 g/cm^3. If the c/a ratio is 1.58, compute the values of c and a.", "answer": "the values of a and c are 0.296 nm and 0.468 nm, respectively.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解Titanium的晶格常数a和c的值，答案给出了具体的数值结果。 | 知识层次: 题目需要应用HCP晶体结构的基本公式，进行多步计算，涉及密度、晶格常数和c/a比的概念关联和综合分析。 | 难度: 在选择题中属于中等偏上难度，需要掌握HCP晶体结构的基本参数关系、密度计算公式，并能正确进行多步单位换算和代数运算。题目涉及c/a比值的应用、原子质量与晶胞体积的关系计算，以及纳米单位的转换，属于需要综合应用多个材料科学概念的题目。虽然选择题提供了正确选项降低了部分难度，但仍需完成较复杂的推导过程才能验证答案。", "convertible": true, "correct_option": "a = 0.296 nm, c = 0.468 nm", "choice_question": "Titanium (Ti) has an HCP crystal structure and a density of 4.51 g/cm^3. If the c/a ratio is 1.58, what are the values of c and a?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "a = 0.296 nm, c = 0.468 nm", "B": "a = 0.295 nm, c = 0.466 nm", "C": "a = 0.468 nm, c = 0.296 nm", "D": "a = 0.301 nm, c = 0.476 nm" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算HCP晶格参数得到的。干扰项B利用数值接近但忽略密度精确计算的陷阱；C通过交换a和c值制造认知偏差；D利用常见单位换算误差（将nm误算为Å）设计专业直觉陷阱。这些干扰项都针对AI在材料参数计算中常见的错误模式设计。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3117, "question": "What are the characteristics of constant expansion alloys?", "answer": "Materials with a certain coefficient of expansion within a specific temperature range are called constant expansion materials.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释constant expansion alloys的特性，答案以文字形式进行解释和论述，符合简答题的特征。 | 知识层次: 题目考查对恒定膨胀合金特性的基本概念记忆和理解，属于定义性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求识别和记忆基础定义，属于最简单的难度等级。正确选项直接给出了恒定膨胀合金的定义，不需要任何解释或分析步骤，仅需基础概念的记忆即可作答。", "convertible": true, "correct_option": "Materials with a certain coefficient of expansion within a specific temperature range are called constant expansion materials.", "choice_question": "Which of the following describes the characteristics of constant expansion alloys?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Materials with a certain coefficient of expansion within a specific temperature range are called constant expansion materials.", "B": "Alloys that maintain zero thermal expansion across all temperature ranges due to perfect atomic lattice compensation.", "C": "Materials exhibiting identical expansion rates in all crystallographic directions regardless of temperature.", "D": "Alloys whose volume remains constant while undergoing phase transformations during heating." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines constant expansion alloys as having a predictable thermal expansion coefficient within a defined temperature range. Option B is a cognitive bias trap exploiting the idealistic but physically impossible concept of zero expansion at all temperatures. Option C is a professional intuition trap suggesting isotropic expansion behavior which isn't required for constant expansion alloys. Option D is a multi-level verification trap combining correct phase transformation concepts with incorrect application to thermal expansion properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3309, "question": "Compare the completeness of isothermal transformation for bainite transformation, pearlite transformation, and martensite transformation", "answer": "Pearlite transformation can be completely transformed, some bainite transformations can be completely transformed while others cannot, and martensite transformation cannot be completely transformed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对不同相变的完整性进行比较和解释，答案提供了详细的文字论述，符合简答题的特征。 | 知识层次: 题目要求比较三种相变（贝氏体、珠光体、马氏体）的等温转变完整性，涉及多个相变过程的概念关联和综合分析。虽然不需要复杂的计算或深度推理，但需要对不同相变的特点和条件有较深入的理解，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合理解三种相变（贝氏体、珠光体、马氏体）的等温转变特性，并进行多角度比较分析。题目要求考生不仅掌握每种相变的基本概念，还需要了解其转变动力学和完成度的差异，涉及多步概念关联和综合分析能力。正确选项的表述也包含了\"部分可以完全转变\"这种需要精确理解的中间状态描述，增加了判断难度。", "convertible": true, "correct_option": "Pearlite transformation can be completely transformed, some bainite transformations can be completely transformed while others cannot, and martensite transformation cannot be completely transformed.", "choice_question": "Compare the completeness of isothermal transformation for bainite transformation, pearlite transformation, and martensite transformation. Which of the following statements is correct?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question because the answer is a specific statement that can be presented as one of the options. The question can be rephrased to ask for the correct statement among given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pearlite transformation can be completely transformed, some bainite transformations can be completely transformed while others cannot, and martensite transformation cannot be completely transformed", "B": "Pearlite and bainite transformations can both be completely transformed, while martensite transformation cannot be completely transformed", "C": "All three transformations can reach 100% completion under isothermal conditions given sufficient time", "D": "Only pearlite transformation can reach full completion, while both bainite and martensite transformations always leave residual austenite" }, "correct_answer": "A", "explanation": "The correct answer is A because pearlite transformation is diffusion-controlled and can reach completion, bainite transformation may or may not complete depending on temperature (upper bainite often incomplete), and martensite is always incomplete due to its athermal nature. Option B is incorrect because it oversimplifies bainite transformation. Option C is wrong as martensite cannot reach full completion isothermally. Option D is incorrect as some bainite transformations can complete. The distractors exploit common misconceptions about transformation completeness and the temperature dependence of bainite formation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 29, "question": "Calculate whether the valence of I- in CdI2 crystal is saturated?", "answer": "In CdI2 crystal, the coordination number (CN) of Cd2+ is 6. I is connected to three Cd2+ on the same side, and the coordination number (CN) of I is 3. Therefore, CN ∑i(z+/CN)=1=1z−1, meaning the valence of I− is saturated.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来判断I-在CdI2晶体中的价态是否饱和，答案提供了详细的解释和计算过程，符合简答题的特征。 | 知识层次: 题目需要理解配位数和价态饱和的概念，并进行多步计算和综合分析，涉及概念关联和中等程度的思维过程。 | 难度: 在选择题中属于较高难度，题目要求考生不仅要理解晶体结构中的配位数概念，还需要进行多步计算和综合分析。具体来说，考生需要：", "convertible": true, "correct_option": "In CdI2 crystal, the coordination number (CN) of Cd2+ is 6. I is connected to three Cd2+ on the same side, and the coordination number (CN) of I is 3. Therefore, CN ∑i(z+/CN)=1=1z−1, meaning the valence of I− is saturated.", "choice_question": "Which of the following correctly describes the valence of I- in CdI2 crystal?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The valence is saturated because CN(I)=3 and each I- shares 1/3 of its charge with three Cd2+ ions", "B": "The valence is unsaturated because I- in CdI2 adopts a tetrahedral coordination geometry", "C": "The valence is saturated due to the 8-N rule where I (group VII) forms one bond", "D": "The valence is unsaturated as the bond valence sum exceeds the formal oxidation state" }, "correct_answer": "A", "explanation": "Correct answer A considers the actual coordination environment where each I- is bonded to 3 Cd2+ (CN=3) with bond valence of 1/3 each, satisfying the valence sum rule. B is wrong by using incorrect geometry (actual structure is layered octahedral). C misapplies the 8-N rule which doesn't account for coordination environment. D reverses the valence calculation logic by comparing to oxidation state rather than coordination requirements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1819, "question": "The essence of a crystal is (2)", "answer": "(2) Particles are arranged in a periodic repetition in three-dimensional space", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案，答案明确对应选项(2) | 知识层次: 题目考查晶体本质的基本概念记忆，仅需理解晶体中粒子在三维空间周期性排列的定义，不涉及复杂分析或应用。 | 难度: 在选择题型中，此题属于基础概念记忆，仅需识别晶体本质的定义即可作答，无需复杂理解或分析。正确选项直接对应晶体结构的基本特征，属于简单概念识别层级。", "convertible": true, "correct_option": "Particles are arranged in a periodic repetition in three-dimensional space", "choice_question": "The essence of a crystal is", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option, making it directly convertible to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Particles are arranged in a periodic repetition in three-dimensional space", "B": "Atoms are packed in the most dense configuration possible", "C": "Electrons are delocalized in a continuous energy band", "D": "Unit cells exhibit perfect translational symmetry at all temperatures" }, "correct_answer": "A", "explanation": "The correct answer A defines the fundamental characteristic of crystals as having a periodically repeating structure in 3D space. Option B is incorrect because dense packing occurs in both crystals and amorphous materials. Option C describes metallic bonding rather than crystallinity. Option D is a trap as it ignores the reality of thermal vibrations disrupting perfect symmetry at finite temperatures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2525, "question": "Explain the term: electronegativity", "answer": "A parameter indicating the ability of an element to attract electrons when forming compounds or solid solutions with other elements.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释术语\"electronegativity\"，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对电负性这一基本概念的定义和记忆，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"电负性\"的基本定义，属于最基础的概念记忆层次。正确选项直接给出了标准定义，不需要进行任何解释、比较或分析，完全符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "A parameter indicating the ability of an element to attract electrons when forming compounds or solid solutions with other elements.", "choice_question": "Which of the following best defines the term 'electronegativity'?", "conversion_reason": "The answer is a standard definition of the term 'electronegativity', which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A parameter indicating the ability of an element to attract electrons when forming compounds or solid solutions with other elements", "B": "The energy required to remove an electron from an atom in its gaseous state", "C": "A measure of the tendency of an atom to donate electrons during ionic bond formation", "D": "The potential energy between two atoms when their electron clouds overlap in covalent bonding" }, "correct_answer": "A", "explanation": "The correct answer is A because electronegativity specifically describes an element's electron-attracting ability in chemical bonds. Option B describes ionization energy, a common confusion due to both involving electron interactions. Option C reverses the concept (describing electropositivity) which can trap systems relying on pattern matching. Option D describes covalent bond energy, exploiting the AI's tendency to associate electronegativity with bonding energy calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3982, "question": "During the recrystallization of a cold-worked material, is some of the internal strain energy relieved?", "answer": "All of the internal strain energy is relieved.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（\"All of the internal strain energy is relieved\"），符合判断题的特征。 | 知识层次: 题目考查对冷加工材料再结晶过程中内应变能变化的基本概念记忆和理解，属于基础概念记忆范畴。 | 难度: 该题目属于基础概念记忆层次，仅需判断关于再结晶过程中内应变能释放的基本陈述是否正确。题目结构简单，无需复杂推理或概念比较，符合选择题型中最基础的难度等级。", "convertible": true, "correct_option": "All of the internal strain energy is relieved.", "choice_question": "During the recrystallization of a cold-worked material, is some of the internal strain energy relieved?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "During recrystallization of a cold-worked material, all dislocations are completely eliminated.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While recrystallization significantly reduces dislocation density by forming new strain-free grains, it does not completely eliminate all dislocations. Some dislocations remain in the recrystallized material due to thermal stresses and the formation of new grain boundaries. This is a common misconception where students may overestimate the completeness of the recrystallization process.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2101, "question": "Under equilibrium cooling conditions, a carbon steel obtains a microstructure consisting of 50% pearlite and 50% ferrite. If it is heated to 850°C, what microstructure will be obtained?", "answer": "Entirely austenite (A) microstructure", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释在特定温度下材料的微观结构变化，答案需要文字描述和论述，而非选择、判断或计算。 | 知识层次: 题目需要理解铁碳相图的基本原理，并能够根据给定的条件（50%珠光体和50%铁素体）推断出钢的碳含量，然后进一步分析在850°C加热时的相变过程。这涉及到多步的概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及碳钢在平衡冷却条件下的微观结构（珠光体和铁素体比例），以及加热到850°C后的相变过程。解答需要综合运用铁碳相图知识，判断在给定温度下钢的相组成，并理解奥氏体形成的条件。虽然不涉及复杂计算，但需要对相变概念有清晰的理解和关联分析能力。", "convertible": true, "correct_option": "Entirely austenite (A) microstructure", "choice_question": "Under equilibrium cooling conditions, a carbon steel obtains a microstructure consisting of 50% pearlite and 50% ferrite. If it is heated to 850°C, what microstructure will be obtained?", "conversion_reason": "The answer is a standard term (austenite microstructure), which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Entirely austenite (γ) microstructure", "B": "50% austenite and 50% cementite", "C": "Retained pearlite-ferrite structure with partial austenitization", "D": "Martensite due to rapid heating rate effects" }, "correct_answer": "A", "explanation": "The correct answer is A because 850°C is above the A3 line for this steel composition (as evidenced by the 50/50 pearlite/ferrite room temperature microstructure), resulting in complete austenitization. Option B exploits confusion between equilibrium cooling and heating phase fractions. Option C targets incomplete phase transformation knowledge by suggesting partial transformation. Option D introduces a heating rate effect that doesn't apply under equilibrium conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 519, "question": "How does temperature affect atomic diffusion in crystalline solids?", "answer": "The higher the temperature, the greater the diffusion coefficient and the faster the diffusion rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释温度对晶体固体中原子扩散的影响，需要文字解释和论述，而不是选择、判断或计算。答案也是以论述形式给出。 | 知识层次: 题目需要理解温度对原子扩散的影响机制，并关联扩散系数与温度的关系，属于中等应用层次的知识点。 | 难度: 在选择题中属于中等难度，需要理解温度与扩散系数之间的关系，并能综合分析温度对扩散速率的影响。虽然不涉及多步计算，但需要对概念进行关联和综合分析。", "convertible": true, "correct_option": "The higher the temperature, the greater the diffusion coefficient and the faster the diffusion rate.", "choice_question": "How does temperature affect atomic diffusion in crystalline solids?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The higher the temperature, the greater the diffusion coefficient due to increased thermal energy overcoming activation barriers", "B": "Diffusion decreases at higher temperatures as atomic vibrations reduce available interstitial sites", "C": "Temperature has no effect on diffusion in crystalline solids due to fixed lattice positions", "D": "Diffusion initially increases then decreases above a critical temperature as lattice vibrations become chaotic" }, "correct_answer": "A", "explanation": "Correct answer A follows the Arrhenius equation where diffusion coefficient increases exponentially with temperature. Option B reverses the correct relationship by incorrectly suggesting reduced interstitial sites. Option C exploits the misconception that crystalline structure implies immobile atoms. Option D creates a false 'optimal temperature' concept that doesn't exist for simple diffusion mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3729, "question": "When a 3000-kg load is applied to a 10-mm-diameter ball in a Brinell test of a steel, an indentation of 3.1mm is produced. Estimate the tensile strength of the steel.", "answer": "the tensile strength of the steel is 194,000 psi.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的负载、直径和压痕尺寸，应用布氏硬度测试的相关公式计算钢的抗拉强度。答案是一个具体的数值结果，需要通过计算得出。 | 知识层次: 题目需要应用布氏硬度测试的基本公式进行多步计算，涉及载荷、压头直径和压痕直径的关联，并进一步推导材料的抗拉强度。虽然计算过程相对直接，但需要理解布氏硬度与抗拉强度之间的关系，并进行适当的单位转换和综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解布氏硬度测试原理、掌握硬度与抗拉强度的转换公式，并进行多步骤计算。题目涉及载荷、压痕直径的测量以及单位换算（mm到inch），最后还需要应用经验公式估算抗拉强度。虽然提供了正确选项，但解题过程需要综合应用材料力学和测试方法知识，属于典型的综合性计算问题。", "convertible": true, "correct_option": "194,000 psi", "choice_question": "When a 3000-kg load is applied to a 10-mm-diameter ball in a Brinell test of a steel, an indentation of 3.1mm is produced. Estimate the tensile strength of the steel.", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "194,000 psi", "B": "137,000 psi", "C": "225,000 psi", "D": "158,000 psi" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Brinell hardness number (BHN) formula and the empirical relationship between BHN and tensile strength for steel. Option B is a common mistake from confusing Brinell with Rockwell hardness conversions. Option C is designed to trap those who incorrectly use the ball diameter instead of indentation diameter in calculations. Option D exploits the tendency to mix up metric and imperial units during intermediate steps.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1867, "question": "What are the methods to prevent secondary recrystallization?", "answer": "Methods to prevent secondary recrystallization: control sintering temperature, sintering time, control the uniformity of raw material particle size, introduce sintering additives.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求列举防止二次再结晶的方法，答案以文字解释和论述的形式给出，没有选项或计算要求。 | 知识层次: 题目要求列举防止二次再结晶的方法，涉及对烧结温度、时间、原料粒径均匀性和烧结添加剂等多个因素的综合考虑，需要将多个概念关联起来进行分析和应用，但不需要深入机理解释或创新设计。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求掌握防止二次再结晶的方法，涉及控制烧结温度、烧结时间、原料颗粒均匀性以及引入烧结添加剂等多个知识点。虽然不需要复杂的计算，但需要对材料科学中的再结晶现象有较深的理解，并能综合分析不同因素对二次再结晶的影响。", "convertible": true, "correct_option": "control sintering temperature, sintering time, control the uniformity of raw material particle size, introduce sintering additives", "choice_question": "Which of the following are methods to prevent secondary recrystallization?", "conversion_reason": "The answer is a list of standard methods, which can be presented as options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "control sintering temperature", "B": "increase cooling rate after sintering", "C": "use materials with higher elastic modulus", "D": "apply external magnetic field during sintering" }, "correct_answer": "A", "explanation": "The correct answer is A because controlling sintering temperature directly affects grain growth kinetics, preventing abnormal grain growth characteristic of secondary recrystallization. Option B exploits cognitive bias by suggesting a common metallurgical practice (fast cooling) that doesn't address recrystallization mechanisms. Option C is a professional intuition trap, misleadingly implying mechanical properties can control microstructural evolution. Option D is a multi-level verification trap, using a real materials science technique (magnetic processing) but in an irrelevant context for recrystallization control.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1870, "question": "The crystal structure with point group L6L27PC belongs to the crystal system. A. Cubic B. Hexagonal C. Tetragonal D. Orthorhombic", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对晶体结构点群和晶系分类的基础概念记忆，属于定义和分类的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生对晶体结构和点群分类有一定的理解和辨析能力。具体来说，考生需要知道L6L27PC对应的晶体系统是Hexagonal，这不仅仅是对定义的简单记忆，还需要对点群符号和晶体系统之间的关系有一定的理解。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "B", "choice_question": "The crystal structure with point group L6L27PC belongs to the crystal system.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy for vacancy diffusion is always lower than interstitial diffusion in FCC metals", "B": "The Peierls stress in BCC metals is typically higher than in FCC metals due to their more open crystal structure", "C": "Twin boundary migration in HCP metals occurs at lower temperatures than in FCC metals because of their lower stacking fault energy", "D": "Grain boundary sliding is the dominant deformation mechanism in nanocrystalline materials at all temperatures" }, "correct_answer": "B", "explanation": "The correct answer is B because the more open structure of BCC metals leads to higher Peierls stress compared to FCC metals. Option A is a cognitive bias trap - while often true, there are exceptions where interstitial diffusion can have lower activation energy. Option C exploits intuition about HCP metals but incorrectly links stacking fault energy to twin boundary migration temperature. Option D is a multi-level verification trap - while grain boundary sliding is important in nanocrystalline materials, it's not dominant at all temperatures (e.g., high temperatures where diffusion becomes significant).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2958, "question": "Carbon atoms take 10 hours to diffuse into the surface of pure iron material at ${800}^{\\\\circ}\\\\mathrm{C}$ to a depth of $0.1\\\\mathfrak{c m}$. Calculate the time required to achieve the same carbon depth at $900^{\\\\circ}\\\\mathrm{C}$. (The diffusion activation energy of carbon atoms in fcc iron is $137520\\\\mathrm{J/mol}$.)", "answer": "Since $D{=}D_{0}\\\\exp(-Q/R T)$, substituting the values gives $D_{800}/D_{500}{=}0.27$. The diffusion depth $x^{2}/(4D t)=$ constant. Substituting the values gives $t_{900}=2.7\\\\mathrm{hr}$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来解决问题，涉及扩散系数和时间的计算，答案也是具体的数值结果。 | 知识层次: 题目涉及多步计算和概念关联，需要应用扩散方程和温度对扩散系数的影响，综合分析不同温度下的扩散时间。虽然不涉及复杂的机理分析或创新设计，但需要理解和应用多个相关概念和公式。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程、温度对扩散系数的影响以及扩散深度与时间的关系。题目涉及多步计算和概念关联，包括使用阿伦尼乌斯方程计算不同温度下的扩散系数比例，以及利用扩散深度公式求解时间。虽然题目提供了正确选项，但解题过程需要综合分析和计算能力。", "convertible": true, "correct_option": "2.7 hr", "choice_question": "Carbon atoms take 10 hours to diffuse into the surface of pure iron material at ${800}^{\\circ}\\mathrm{C}$ to a depth of $0.1\\mathfrak{c m}$. The time required to achieve the same carbon depth at $900^{\\circ}\\mathrm{C}$ is: (The diffusion activation energy of carbon atoms in fcc iron is $137520\\mathrm{J/mol}$.)", "conversion_reason": "The calculation problem has a specific numerical answer, which can be converted into a multiple-choice question format with the correct option being the calculated time.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.7 hr", "B": "5.4 hr", "C": "1.35 hr", "D": "10.8 hr" }, "correct_answer": "A", "explanation": "正确答案A通过Arrhenius方程计算得出。干扰项B利用温度差100°C的直觉错误翻倍时间；干扰项C通过错误应用平方根关系产生；干扰项D通过错误线性外推产生。这些干扰项都利用了材料科学中常见的扩散时间估算误区。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2200, "question": "The melting point of iron is known to be 1,538℃, estimate the minimum recrystallization temperature of iron", "answer": "The minimum recrystallization temperature of iron is T_r=0.4×(1,538+273)=723 K", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计铁的再结晶温度，答案给出了具体的计算过程和结果。 | 知识层次: 题目涉及基本的公式应用和简单计算，只需将已知的熔点转换为绝对温度后乘以经验系数0.4即可得到再结晶温度，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（T_r=0.4×(T_m+273)）并进行简单计算，无需额外的概念理解或步骤组合。属于最基础的公式应用和计算难度。", "convertible": true, "correct_option": "723 K", "choice_question": "The minimum recrystallization temperature of iron is estimated to be:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "723 K", "B": "0.4 × melting point (615 K)", "C": "0.6 × melting point (923 K)", "D": "Iron's Curie temperature (1043 K)" }, "correct_answer": "A", "explanation": "The correct answer is 723 K, which is the empirically determined minimum recrystallization temperature for iron. Option B (615 K) exploits the common misconception that recrystallization temperature is always 0.4×melting point, but this rule has exceptions. Option C (923 K) uses the more accurate 0.6×melting point rule but still fails for iron's specific case. Option D (1043 K) is a professional intuition trap, using iron's real Curie temperature which is irrelevant to recrystallization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2603, "question": "In multi-electron atoms, what principles should the arrangement of extranuclear electrons follow?", "answer": "The principle of lowest energy, Pauli exclusion principle, Hund's rule.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释多电子原子中核外电子排布遵循的原则，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对多电子原子核外电子排布遵循的基本原则的记忆和理解，包括能量最低原理、泡利不相容原理和洪特规则，这些都是材料科学中的基础概念，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生记忆并理解多电子原子中核外电子排布的三个基本原理（最低能量原理、泡利不相容原理和洪德规则）。虽然涉及多个概念，但都属于基础概念的记忆和简单应用，不需要复杂的分析或推理。因此属于中等难度（等级2）。", "convertible": true, "correct_option": "The principle of lowest energy, Pauli exclusion principle, Hund's rule", "choice_question": "In multi-electron atoms, what principles should the arrangement of extranuclear electrons follow?", "conversion_reason": "The answer is a standard set of principles, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The principle of lowest energy, Pauli exclusion principle, Hund's rule", "B": "Aufbau principle, Heisenberg uncertainty principle, Hund's rule", "C": "Pauli exclusion principle, Hund's rule, Born-Oppenheimer approximation", "D": "Principle of lowest energy, Pauli exclusion principle, Fermi-Dirac statistics" }, "correct_answer": "A", "explanation": "The correct answer is A because the arrangement of extranuclear electrons in multi-electron atoms must follow these three fundamental principles: 1) electrons occupy the lowest energy orbitals available (principle of lowest energy), 2) no two electrons can have identical quantum numbers (Pauli exclusion principle), and 3) orbitals of equal energy are occupied singly before pairing occurs (Hund's rule). Option B incorrectly includes the Heisenberg uncertainty principle, which relates to position/momentum measurement, not electron arrangement. Option C incorrectly includes the Born-Oppenheimer approximation, which is about separating nuclear and electronic motion. Option D incorrectly substitutes Fermi-Dirac statistics (which describes particle distribution in quantum systems) for Hund's rule.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2045, "question": "Given that the density of fully crystalline polyethylene (PE) is 1.01 g/cm³ and that of high-density polyethylene (HDPE) is 0.96 g/cm³, calculate the size of the 'free space' in HDPE.", "answer": "The free space in HDPE is (1 cm³ / 0.96 g) - (1 cm³ / 1.01 g) = 0.052 cm³/g", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过计算得出的具体数值 | 知识层次: 题目需要进行基本的密度计算和简单的公式应用，涉及直接套用已知数据进行数值计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用给定的密度公式进行计算，属于单一公式直接计算的类型。解题步骤简单明确，无需复杂的推理或多步骤运算，符合等级1的难度标准。", "convertible": true, "correct_option": "0.052 cm³/g", "choice_question": "Given that the density of fully crystalline polyethylene (PE) is 1.01 g/cm³ and that of high-density polyethylene (HDPE) is 0.96 g/cm³, what is the size of the 'free space' in HDPE?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.052 cm³/g", "B": "0.048 cm³/g", "C": "0.96 cm³/g", "D": "0.05 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer is A (0.052 cm³/g) calculated as (1/0.96 - 1/1.01). Option B is a common calculation error from (1.01-0.96). Option C is the density value misused as free space. Option D has incorrect units and reverses the calculation logic.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3891, "question": "The atomic number of an electrically neutral atom is equal to the number of:(a) protons (b) electrons (c) neutrons (d)Choose all that apply.", "answer": "(b)electrons.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择正确答案，并且提供了明确的选项(a)-(d)，符合选择题的特征。 | 知识层次: 题目考查原子序数与电子数的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅需直接记忆原子序数与电子数的关系，属于基础概念记忆层次，无需复杂分析或理解多个概念。", "convertible": true, "correct_option": "electrons", "choice_question": "The atomic number of an electrically neutral atom is equal to the number of:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The number of protons in the nucleus", "B": "The sum of protons and neutrons in the nucleus", "C": "The number of electrons in the outermost shell", "D": "The total number of electrons in the atom" }, "correct_answer": "A", "explanation": "The atomic number is defined as the number of protons in the nucleus, which is the correct answer (A). Option B is a common confusion with mass number, creating a cognitive bias trap. Option C exploits the misconception that atomic number relates to valence electrons, a professional intuition trap. Option D is technically correct for neutral atoms but is a verification trap since the question specifically asks about atomic number definition, not neutral atom conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 137, "question": "The melt viscosity is 10^7 Pa·s at 727°C and 10^3 Pa·s at 1156°C. At what temperature will it be 10^6 Pa·s?", "answer": "According to logη=A+B/T, at 727°C, η=10^7 Pa·s, the equation gives: log10^7=A+B/(727+273) (1). At 1156°C, η=10^3 Pa·s, the equation gives: log10^3=A+B/(1156+273) (2). Solving equations (1) and (2) simultaneously yields A=-6.32 and B=13324. When η=10^6 Pa·s, log10^6=-6.32+13324/(t+273), solving gives t=808.5°C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解特定温度下的熔体粘度，解答过程涉及对数运算和联立方程的求解，属于典型的计算题类型。 | 知识层次: 题目需要应用粘度与温度关系的公式，并进行多步计算和联立方程求解，涉及概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解粘度与温度的关系公式（logη=A+B/T），并能够建立两个方程联立求解未知参数A和B。随后还需代入新的粘度值求解温度，涉及多步计算和代数运算。虽然题目提供了明确的解题路径，但步骤较多且需要一定的数学技巧，因此在选择题型内属于综合性计算问题。", "convertible": true, "correct_option": "808.5°C", "choice_question": "The melt viscosity is 10^7 Pa·s at 727°C and 10^3 Pa·s at 1156°C. At what temperature will it be 10^6 Pa·s?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct option among possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "808.5°C", "B": "927°C", "C": "1024°C", "D": "689°C" }, "correct_answer": "A", "explanation": "正确答案A是通过Arrhenius方程精确计算得到的。干扰项B利用了常见玻璃转变温度的直觉偏差；干扰项C利用了高温区域粘度变化速率减半的认知误区；干扰项D则基于低温区域外推的错误假设。所有干扰项都针对AI在材料科学中常见的温度-粘度关系理解弱点设计。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2941, "question": "The relationship between the probability of annealing twin formation and the stacking fault energy of the crystal is (A) unrelated, only dependent on the annealing temperature and time (B) crystals with low stacking fault energy have a higher probability of forming annealing twins (C) crystals with high stacking fault energy have a higher probability of forming annealing twins", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（A、B、C）中选择正确答案 | 知识层次: 题目考查对堆垛层错能与退火孪晶形成概率关系这一基本概念的记忆和理解，属于基础概念记忆范畴。 | 难度: 在选择题中属于中等偏下难度，需要理解堆垛层错能与退火孪晶形成概率之间的关系这一基础概念，并进行简单辨析。虽然涉及基本原理的记忆，但选项之间的区分度较高，正确选项较为明显。", "convertible": true, "correct_option": "B", "choice_question": "The relationship between the probability of annealing twin formation and the stacking fault energy of the crystal is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress for twinning decreases with increasing temperature in BCC metals", "B": "Twinning is the dominant deformation mechanism in FCC metals at room temperature", "C": "The twinning stress in HCP metals is inversely proportional to the c/a ratio", "D": "Twinning and slip always occur simultaneously in all crystal structures" }, "correct_answer": "A", "explanation": "The correct answer is A because in BCC metals, the critical resolved shear stress for twinning does decrease with increasing temperature due to thermal activation overcoming the Peierls barrier. Option B is incorrect because slip, not twinning, is dominant in FCC metals at room temperature - this exploits the common confusion between FCC and HCP deformation mechanisms. Option C is a half-truth trap: while c/a ratio affects twinning in HCP metals, the relationship is not simple inverse proportionality. Option D is an absolute statement trap that ignores material-specific deformation behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4696, "question": "In your own words, briefly define the term stoichiometric.", "answer": "Stoichiometric means having exactly the ratio of anions to cations as specified by the chemical formula for the compound.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用自己的话简要解释术语\"stoichiometric\"，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查基本概念的记忆和理解，要求对\"stoichiometric\"这一术语进行定义，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并复述\"stoichiometric\"的基本定义，属于最基础的概念记忆层次。正确选项直接给出了术语的标准定义，不需要任何解释、分析或应用过程，完全符合等级1\"基本定义简答\"的标准。这类题目在选择题中属于最简单的一类，只需识别定义即可作答。", "convertible": true, "correct_option": "Stoichiometric means having exactly the ratio of anions to cations as specified by the chemical formula for the compound.", "choice_question": "Which of the following best defines the term stoichiometric?", "conversion_reason": "The answer is a standard definition of a chemical term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Stoichiometric means having exactly the ratio of anions to cations as specified by the chemical formula for the compound", "B": "Stoichiometric refers to materials with perfect crystalline structure without any defects", "C": "Stoichiometric describes compounds where the sum of ionic radii matches the unit cell dimensions", "D": "Stoichiometric indicates materials that exhibit both ionic and covalent bonding characteristics" }, "correct_answer": "A", "explanation": "Option A is correct as stoichiometry strictly refers to the exact atomic ratio in chemical compounds. Option B exploits confusion with perfect crystals, which is unrelated to stoichiometry. Option C combines valid material concepts (ionic radii and unit cells) in an incorrect context. Option D creates a false connection between bonding characteristics and stoichiometric ratios, which are independent concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1544, "question": "Taking the tensile curve of low-carbon steel as an example, use dislocation theory to explain the phenomenon of work hardening", "answer": "When deformation continues, the stress increases again due to a significant rise in the number of dislocations, a phenomenon known as work hardening. This occurs because cold-deformed metals generate a large number of dislocations during plastic deformation, some of which become immobile dislocations. These immobile dislocations increase resistance to mobile dislocations, making further deformation of the material more difficult, resulting in work hardening or strain hardening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求用位错理论解释低碳钢拉伸曲线中的加工硬化现象，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求运用位错理论解释低碳钢拉伸曲线中的加工硬化现象，涉及位错运动的机理、位错间的相互作用以及材料变形行为的综合分析。这需要深入理解位错理论，并能将其与材料的宏观力学行为联系起来，属于复杂分析和机理解释的范畴。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生运用位错理论解释低碳钢拉伸曲线中的加工硬化现象，涉及复杂的机理分析和综合推理。正确选项不仅需要理解位错运动的基本概念，还需要掌握位错增殖、不动位错形成及其对材料变形抗力的影响机制。这种题目在选择题中属于对知识深度和应用能力要求极高的类型，需要考生将多个高阶概念整合并建立因果关系，完全符合\"复杂现象全面分析\"的等级5标准。", "convertible": true, "correct_option": "When deformation continues, the stress increases again due to a significant rise in the number of dislocations, a phenomenon known as work hardening. This occurs because cold-deformed metals generate a large number of dislocations during plastic deformation, some of which become immobile dislocations. These immobile dislocations increase resistance to mobile dislocations, making further deformation of the material more difficult, resulting in work hardening or strain hardening.", "choice_question": "Taking the tensile curve of low-carbon steel as an example, which of the following best explains the phenomenon of work hardening according to dislocation theory?", "conversion_reason": "The answer is a standard explanation of a concept (work hardening) and can be rephrased into a 'which of the following' format suitable for a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Work hardening occurs due to the formation of immobile dislocation tangles that impede further dislocation motion, requiring higher stress for continued plastic deformation", "B": "The yield plateau in low-carbon steel is caused by dynamic strain aging where solute atoms temporarily pin dislocations, leading to localized softening", "C": "Dislocation annihilation at grain boundaries reduces strain energy, causing the observed stress drop after yielding", "D": "The initial elastic modulus decreases with strain due to dislocation multiplication, resulting in apparent hardening" }, "correct_answer": "A", "explanation": "Option A correctly describes work hardening through dislocation interactions. Option B confuses work hardening with dynamic strain aging. Option C incorrectly attributes stress behavior to dislocation annihilation. Option D falsely suggests modulus changes cause hardening.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1722, "question": "Why does constitutional supercooling occur during the solidification of multicomponent alloys?", "answer": "During the solidification of multicomponent alloys, elements with higher melting points solidify first. If the alloy is not sufficiently stirred, elements with lower melting points will become enriched at the solidification interface front, lowering the actual solidification temperature of the liquid phase there. Even under a positive temperature gradient, the degree of supercooling at the solidification interface front may increase with distance from the interface. This phenomenon is called constitutional supercooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释\"constitutional supercooling\"现象的原因，需要文字论述和解释，而不是选择、判断或计算。答案提供了详细的文字说明来解释这一现象。 | 知识层次: 题目要求解释多组分合金凝固过程中的成分过冷现象，涉及多元素凝固顺序、界面富集、实际凝固温度变化等复杂机理的综合分析，需要深入理解热力学和动力学原理并进行推理解释。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求深入理解多组分合金凝固过程中的成分过冷现象，涉及多个复杂概念的整合（如熔点差异、界面富集、温度梯度等）。正确选项不仅需要解释机理，还需要综合推理实际凝固温度变化与界面距离的关系。这种复杂现象全面分析的题目在选择题中属于对专业知识和分析能力要求极高的类型，远超基础概念题和简单应用题的难度。", "convertible": true, "correct_option": "During the solidification of multicomponent alloys, elements with higher melting points solidify first. If the alloy is not sufficiently stirred, elements with lower melting points will become enriched at the solidification interface front, lowering the actual solidification temperature of the liquid phase there. Even under a positive temperature gradient, the degree of supercooling at the solidification interface front may increase with distance from the interface. This phenomenon is called constitutional supercooling.", "choice_question": "Why does constitutional supercooling occur during the solidification of multicomponent alloys?", "conversion_reason": "The answer is a standard explanation of a specific phenomenon, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Due to solute partitioning creating a composition gradient that locally depresses the liquidus temperature below the actual temperature", "B": "Because the latent heat of fusion cannot be dissipated quickly enough through the solid phase", "C": "When the thermal conductivity of the solid phase exceeds that of the liquid phase", "D": "As a result of anisotropic surface energy causing preferential crystal growth directions" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual mechanism where solute rejection creates a composition gradient that locally alters phase equilibrium. B incorrectly attributes it to heat transfer limitations (thermal supercooling). C reverses the typical conductivity relationship and is irrelevant. D describes crystallographic growth phenomena unrelated to composition effects. Advanced AIs may select B due to overemphasis on thermal effects or D due to surface energy being a common consideration in solidification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3539, "question": "How to choose tin-based and lead-based babbitt alloys?", "answer": "Tin-based bearing alloys are suitable for high-speed bearings. Lead-based bearing alloys are mostly used for small and low-speed ordinary machinery.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释如何选择锡基和铅基巴氏合金，答案提供了文字解释和论述，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目考查对锡基和铅基巴氏合金选择的基本概念记忆和理解，涉及它们的适用场景分类，不需要复杂的分析或综合应用。 | 难度: 该题目属于选择题型中的概念解释和描述难度等级。题目要求考生区分锡基和铅基巴氏合金的应用场景，这需要理解两种合金的基本特性和适用条件，但不需要深入分析或比较复杂的体系。正确选项直接提供了两种合金的典型应用场景，属于对基础概念的记忆和应用，符合等级2的描述。", "convertible": true, "correct_option": "Tin-based bearing alloys are suitable for high-speed bearings. Lead-based bearing alloys are mostly used for small and low-speed ordinary machinery.", "choice_question": "Which of the following statements correctly describes the use of tin-based and lead-based babbitt alloys?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct statement about the use of these alloys.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Tin-based alloys exhibit better fatigue resistance at high speeds due to their higher thermal conductivity", "B": "Lead-based alloys are preferred for high-load applications because of their superior hardness", "C": "Tin-based alloys contain antimony which forms hard cuboids that improve wear resistance at all speeds", "D": "Lead-based alloys should never be used in marine environments due to rapid galvanic corrosion" }, "correct_answer": "A", "explanation": "Correct answer A is right because tin-based alloys' superior thermal conductivity helps dissipate heat at high speeds, preventing fatigue. Option B is a hardness fallacy - while lead alloys are harder, their lower melting point makes them unsuitable for high loads. Option C is a cuboid overgeneralization - while SbSn cuboids exist, they're ineffective at very low speeds. Option D is an environmental oversimplification - lead alloys can be used in marine applications with proper cathodic protection.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1424, "question": "By what mechanism do ceramic materials conduct heat?", "answer": "Ceramic materials primarily conduct heat through phonons", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释陶瓷材料传导热量的机制，答案需要文字论述而非选择、判断或计算 | 知识层次: 题目考查陶瓷材料导热机制的基本概念，仅需记忆和理解\"phonons\"这一基本原理即可回答，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，此题仅需记忆陶瓷材料导热的基本机制（声子传导），属于最基础的定义性知识。题目不涉及概念解释或复杂体系分析，只需识别正确选项即可，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Ceramic materials primarily conduct heat through phonons", "choice_question": "By what mechanism do ceramic materials primarily conduct heat?", "conversion_reason": "The answer is a standard term or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Phonon lattice vibrations", "B": "Free electron movement", "C": "Photon emission/absorption", "D": "Atomic diffusion" }, "correct_answer": "A", "explanation": "Ceramics primarily conduct heat through phonons (lattice vibrations) due to their ionic/covalent bonding and band gap that prevents significant free electron movement. Option B exploits the common misconception that all thermal conduction resembles metals. Option C targets confusion with radiative heat transfer. Option D leverages the intuitive but incorrect idea that atomic motion directly transfers heat in solids.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3888, "question": "The nucleus of an atom contains electrons?", "answer": "No, the nucleus of an atom does not contain electrons.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（对/错），答案直接给出了判断结果（No）和解释。 | 知识层次: 题目考查原子核组成的基本概念记忆，属于最基础的定义性知识，仅需记忆即可回答。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆原子核的基本组成（质子和中子）即可判断正确选项。题目不涉及概念理解或复杂陈述，属于最基础的知识点考察。", "convertible": true, "correct_option": "No, the nucleus of an atom does not contain electrons.", "choice_question": "The nucleus of an atom contains electrons?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials are inherently brittle at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain advanced ceramics like transformation-toughened zirconia exhibit significant fracture toughness due to stress-induced phase transformations that inhibit crack propagation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 390, "question": "Both edge dislocations and screw dislocations have climb and glide motions.", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目给出一个陈述（Both edge dislocations and screw dislocations have climb and glide motions），要求判断其正误（答案给出×表示错误），符合判断题的特征 | 知识层次: 题目考查对位错类型及其运动方式的基本概念记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度等级。题目考察的是对位错运动方式的基本理解，需要区分边缘位错和螺型位错的不同运动特性（边缘位错有攀移和滑移，而螺型位错只有滑移）。虽然涉及两个概念，但属于基础概念记忆层次，不需要复杂的分析步骤。", "convertible": true, "correct_option": "×", "choice_question": "Both edge dislocations and screw dislocations have climb and glide motions.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, some transformation-toughened ceramics like partially stabilized zirconia can exhibit significant plastic deformation due to stress-induced phase transformations. This statement is false because it uses the absolute term 'all' which doesn't account for these exceptions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4330, "question": "Consider 1.0 kg of austenite containing 1.15 wt % C, cooled to below 727 C (1341 F). How many kilograms each of total ferrite and cementite form?", "answer": "the total ferrite formed is 0.83 kg, and the total cementite formed is 0.17 kg.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算确定铁素体和渗碳体的质量，需要应用相图和相关公式进行计算，最终给出具体的数值结果。 | 知识层次: 题目需要应用铁碳相图的知识，进行多步计算以确定不同相的含量。虽然涉及基础概念，但需要理解相变过程并运用杠杆定律进行计算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图、杠杆定律等概念，并进行多步计算和综合分析。虽然题目给出了正确选项，但解题过程涉及多个知识点的关联应用和较复杂的计算步骤，超出了简单记忆或单一概念应用的范畴。", "convertible": true, "correct_option": "the total ferrite formed is 0.83 kg, and the total cementite formed is 0.17 kg", "choice_question": "Consider 1.0 kg of austenite containing 1.15 wt % C, cooled to below 727 C (1341 F). How many kilograms each of total ferrite and cementite form?", "conversion_reason": "The answer is a specific and deterministic calculation result, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.83 kg ferrite and 0.17 kg cementite", "B": "0.85 kg ferrite and 0.15 kg cementite", "C": "0.80 kg ferrite and 0.20 kg cementite", "D": "0.77 kg ferrite and 0.23 kg cementite" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately applies the lever rule to the eutectoid composition (0.77 wt% C) and the given composition (1.15 wt% C). Option B is a common error from misapplying the lever rule by using 1.0 wt% C as a reference point. Option C results from incorrectly assuming a linear proportion between the eutectoid and cementite compositions. Option D arises from confusing the problem with hypoeutectoid steel calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 733, "question": "The crystal structure with point group $\\\\bf F m3m$ belongs to the crystal system. (a) cubic (b) hexagonal (c) tetragonal (d) orthorhombic", "answer": "a", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(a)(b)(c)(d)中选择正确答案 | 知识层次: 题目考查对晶体结构和点群分类的基础概念记忆，只需识别$F m3m$属于立方晶系即可，无需复杂分析或计算。 | 难度: 该题目属于基础概念记忆类型，仅需识别点群符号$F m3m$对应的晶系即可。在选择题型中，这是最直接的记忆性知识应用，无需复杂理解或辨析步骤。", "convertible": true, "correct_option": "a", "choice_question": "The crystal structure with point group $\\bf F m3m$ belongs to the crystal system.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy for vacancy formation decreases with increasing temperature due to enhanced atomic vibrations", "B": "The activation energy for vacancy formation is independent of temperature but depends on crystal structure", "C": "The activation energy for vacancy formation increases with temperature due to stronger atomic bonds", "D": "The activation energy for vacancy formation shows a non-monotonic temperature dependence" }, "correct_answer": "B", "explanation": "The correct answer is B because activation energy is an intrinsic material property determined by the energy required to form a vacancy in the crystal lattice, which depends on the bonding environment (crystal structure) but not temperature. Option A exploits the common misconception that thermal activation directly reduces energy barriers. Option C creates confusion by suggesting bond strengthening at higher temperatures. Option D introduces a complex but irrelevant temperature dependence pattern that might trap overthinking models.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3909, "question": "If the atomic radius of a metal that has the face-centered cubic crystal structure is 0.123nm, calculate the volume of its unit cell.", "answer": "\\[\nv_{c}=0.258nm^{3}\n\\]", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解单位晶胞的体积，答案是一个具体的数值结果。 | 知识层次: 题目要求应用面心立方晶体结构的基本公式计算单位晶胞体积，属于直接套用公式的简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用面心立方晶体结构的单位晶胞体积公式（Vc = (4r/√2)^3），并进行简单的数值计算。题目提供了所有必要的信息（原子半径r=0.123nm），且无需额外的推导或组合公式。因此，在选择题型内属于最低难度等级，即单一公式直接计算。", "convertible": true, "correct_option": "0.258nm³", "choice_question": "If the atomic radius of a metal that has the face-centered cubic crystal structure is 0.123nm, what is the volume of its unit cell?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.258nm³", "B": "0.183nm³", "C": "0.321nm³", "D": "0.416nm³" }, "correct_answer": "A", "explanation": "The correct answer is A (0.258nm³) because for an FCC structure, the lattice parameter 'a' is related to the atomic radius 'r' by a = 2√2r. With r=0.123nm, a=0.348nm, and the unit cell volume is a³=0.258nm³. Option B (0.183nm³) is a common error from using the wrong relationship a=2r (simple cubic). Option C (0.321nm³) comes from incorrectly using a=4r/√3 (BCC structure). Option D (0.416nm³) is a distractor based on misapplying the atomic packing factor calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1961, "question": "An FCC crystal yields under a normal stress of 2MPa in the [123] direction. The activated slip system has been measured as (111)[101]. Determine the resolved shear stress τ that activates this slip system.", "answer": "$$ \\\\begin{array}{l}\\\\cos\\\\phi=\\\\frac{[\\\\overline{1}23]}{|[\\\\overline{1}23]|}\\\\cdot\\\\frac{[111]}{|[111]|}=\\\\frac{-1+2+3}{\\\\sqrt{14}\\\\sqrt{3}}=0.617\\\\\\\\ \\\\cos\\\\lambda=\\\\frac{[\\\\overline{1}23]}{|[\\\\overline{1}23]|}\\\\cdot\\\\frac{[\\\\overline{1}01]}{|[\\\\overline{1}01]|}=\\\\frac{1+0+3}{\\\\sqrt{14}\\\\sqrt{2}}=0.756\\\\end{array}$$ $$\\\\tau=2\\\\times0.617\\\\times0.756\\\\mathrm{MPa}=0.933\\\\mathrm{MPa}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定解析剪切应力τ，答案中包含了具体的数学计算过程和结果，符合计算题的特征。 | 知识层次: 题目需要多步计算和概念关联，包括向量点积计算、方向余弦求解以及Schmid因子应用，涉及晶体学方向指数和滑移系统的综合分析，但不需要复杂的推理或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体学方向指数、滑移系统、分解剪应力等概念，并进行多步向量点积计算。虽然题目提供了正确选项的计算过程，但需要考生具备综合分析能力和准确执行数学运算的技能。", "convertible": true, "correct_option": "0.933 MPa", "choice_question": "An FCC crystal yields under a normal stress of 2MPa in the [123] direction. The activated slip system has been measured as (111)[101]. Determine the resolved shear stress τ that activates this slip system.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible but incorrect values.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.933 MPa", "B": "1.732 MPa", "C": "0.816 MPa", "D": "1.414 MPa" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算施密特因子得到的：cosφ=([123]·[111])/(|[123]||[111]|)=8/√14√3, cosλ=([123]·[101])/(|[123]||[101]|)=5/√14√2, τ=σcosφcosλ=2*(8/√42)*(5/√28)=0.933 MPa。干扰项B是直接计算[123]与[101]的点积(2+0+3=5)除以|[101]|(√2)的陷阱。干扰项C错误地使用了(111)面法向与应力轴的夹角计算。干扰项D是√2的常见数值陷阱，利用对FCC滑移系的本能联想。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2776, "question": "Given that the recrystallization activation energy of a $\\mathtt{C u}{\\sim}30\\%\\mathtt{Z n}$ alloy is $250\\mathrm{kJ/mol}$, and it takes 1 hour for this alloy to complete recrystallization at a constant temperature of $400^{\\circ}C$, calculate how many hours it will take for this alloy to complete recrystallization at a constant temperature of $390\\mathrm{\\textperthousand}$.", "answer": "Solution: Using the formula $$ \\frac{t_{2}}{t_{1}}{=}\\ e^{-\\frac{Q}{R}\\left(\\frac{1}{T_{1}}-\\frac{1}{T_{2}}\\right)},$$ thus $$ \\begin{array}{r l}&{\\frac{t_{2}}{t_{1}}{=}\\exp\\Big({-}\\frac{Q}{R}\\Big(\\frac{1}{T_{1}}{-}\\frac{1}{T_{2}}\\Big)\\Big)}\\ &{\\quad\\quad{=}\\exp\\Big({-}\\frac{250\\times10^{3}}{8.314}\\Big(\\frac{1}{400+273}{-}\\frac{1}{390+273}\\Big)\\Big)}\\ &{\\quad{=}1.962}\\end{array}$$ Therefore, it will take 1.962 hours.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来解决问题，答案中包含了具体的计算步骤和最终数值结果。 | 知识层次: 题目涉及多步计算和公式应用，需要理解并运用阿伦尼乌斯公式进行温度对再结晶时间影响的定量计算，同时需要单位转换和数值计算能力。虽然不涉及复杂的机理分析或创新设计，但比简单应用更复杂，需要一定的综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解再结晶激活能的概念，掌握阿伦尼乌斯公式的应用，并进行多步温度转换和指数计算。虽然题目提供了公式，但需要正确代入数值并处理单位转换（如温度从摄氏度转换为开尔文），最后还需进行指数运算得出结果。这种综合性计算问题在选择题中属于较复杂的类型。", "convertible": true, "correct_option": "1.962 hours", "choice_question": "Given that the recrystallization activation energy of a $\\mathtt{C u}{\\sim}30\\%\\mathtt{Z n}$ alloy is $250\\mathrm{kJ/mol}$, and it takes 1 hour for this alloy to complete recrystallization at a constant temperature of $400^{\\circ}C$, calculate how many hours it will take for this alloy to complete recrystallization at a constant temperature of $390\\mathrm{\\textperthousand}$.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.962 hours", "B": "0.510 hours", "C": "2.450 hours", "D": "1.000 hours" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Arrhenius equation for recrystallization kinetics. The time ratio is given by exp[(Q/R)(1/T2 - 1/T1)], where Q=250 kJ/mol, R=8.314 J/mol·K, T1=673K (400°C), T2=663K (390°C). Option B is a common error from incorrectly converting temperature units or misapplying the activation energy. Option C results from mistakenly using the reciprocal of the correct time ratio. Option D is a trap for those who assume negligible temperature effect without calculation. The subtle temperature difference (10°C) combined with the high activation energy creates a non-intuitive result that challenges AI's physical intuition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3956, "question": "A steel bar 100mm (4.0 in.) long and having a square cross section 20mm (0.8 in.) on an edge is pulled in tension with a load of 89,000N\\left(20,000 lb_{0}\\right), and experiences an elongation of 0.10mm (4.0 × 10^{-3} in.). Assuming that the deformation is entirely elastic, calculate the elastic modulus of the steel.", "answer": "the elastic modulus of the steel is 223 \\text{ gpa} (31.3 × 10^6 \\text{ psi}).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解钢的弹性模量，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目要求应用胡克定律进行简单的弹性模量计算，仅涉及基本公式的直接套用和单步数值计算，不需要多步推导或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用弹性模量的基本公式（应力/应变），但计算步骤较为直接，仅涉及简单的单位转换和代数运算。题目提供了所有必要的数据，且变形假设为完全弹性，无需考虑复杂情况。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "223 GPa (31.3 × 10^6 psi)", "choice_question": "A steel bar 100mm (4.0 in.) long and having a square cross section 20mm (0.8 in.) on an edge is pulled in tension with a load of 89,000N (20,000 lb₀), and experiences an elongation of 0.10mm (4.0 × 10⁻³ in.). Assuming that the deformation is entirely elastic, the elastic modulus of the steel is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "223 GPa (31.3 × 10^6 psi)", "B": "112 GPa (16.2 × 10^6 psi)", "C": "446 GPa (64.7 × 10^6 psi)", "D": "69 GPa (10.0 × 10^6 psi)" }, "correct_answer": "A", "explanation": "The correct answer is calculated using Hooke's Law (σ = Eε) where stress (σ) is force divided by cross-sectional area (89,000N / (20mm × 20mm)) and strain (ε) is elongation divided by original length (0.10mm / 100mm). Option B is half the correct value, exploiting a common calculation error where students forget to square the edge length for area. Option C is double the correct value, targeting those who confuse total elongation with strain rate. Option D uses the shear modulus value for steel (69 GPa), exploiting confusion between elastic and shear moduli in isotropic materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2783, "question": "Given a diffusion couple composed of pure chromium and pure iron, after 1 hour of diffusion, the Matano plane moved by 1.52×10^(-3) cm. It is known that the ratio of the square of the distance moved by the Matano plane to the diffusion time is a constant. Determine the moving speed of the Matano plane.", "answer": "According to the given conditions: x²/t = k, the moving speed of the Matano plane vₐ = dx/dt = k/(2x) = x/(2t) = (1.52×10^(-3))/(2×3600) cm/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，解答过程涉及数学运算和物理公式的使用，最终给出具体的数值结果。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即根据给定的条件和公式直接计算Matano平面的移动速度，不需要多步计算或复杂的概念关联。 | 难度: 在选择题中属于简单公式应用计算难度，题目要求直接套用给定的公式x²/t = k，并通过简单的代数变换和数值代入计算出Matano平面的移动速度。解题步骤清晰且直接，不需要复杂的推理或多步骤计算，符合等级2的标准。", "convertible": true, "correct_option": "(1.52×10^(-3))/(2×3600) cm/s", "choice_question": "Given a diffusion couple composed of pure chromium and pure iron, after 1 hour of diffusion, the Matano plane moved by 1.52×10^(-3) cm. It is known that the ratio of the square of the distance moved by the Matano plane to the diffusion time is a constant. Determine the moving speed of the Matano plane.", "conversion_reason": "The question can be converted into a multiple-choice format because the answer is a specific numerical value derived from the given conditions. The correct option can be directly extracted from the provided solution.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.52×10^(-3)/3600 cm/s", "B": "1.52×10^(-3)/7200 cm/s", "C": "(1.52×10^(-3))^2/3600 cm/s", "D": "1.52×10^(-3) cm/s" }, "correct_answer": "B", "explanation": "The correct answer is B because the Matano plane's speed is calculated by dividing the displacement by twice the diffusion time (x^2/t = constant implies dx/dt = x/2t). Option A is a trap for those who incorrectly use simple displacement/time. Option C exploits confusion between displacement and its square. Option D is a dimensional mismatch trap using raw displacement as speed.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 183, "question": "What is adsorption?", "answer": "Adsorption is the result of the interaction between the force field on the surface of a solid and the force field of the adsorbed molecules, occurring on the solid surface, and is divided into physical adsorption and chemical adsorption.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"adsorption\"进行定义和解释，答案提供了详细的文字描述和分类，符合简答题的特征 | 知识层次: 题目考查吸附的基本定义和分类，属于基础概念的记忆和理解 | 难度: 在选择题中属于中等难度，题目要求考生不仅记忆吸附的基本定义，还需要理解其分类（物理吸附和化学吸附）和基本原理（表面力场相互作用）。虽然不涉及复杂概念体系阐述，但比单纯的定义简答要求更高层次的理解。", "convertible": true, "correct_option": "Adsorption is the result of the interaction between the force field on the surface of a solid and the force field of the adsorbed molecules, occurring on the solid surface, and is divided into physical adsorption and chemical adsorption.", "choice_question": "Which of the following best defines adsorption?", "conversion_reason": "The answer is a standard definition of a scientific term, which can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Adsorption is the result of the interaction between the force field on the surface of a solid and the force field of the adsorbed molecules, occurring on the solid surface, and is divided into physical adsorption and chemical adsorption.", "B": "Adsorption is the absorption of molecules into the bulk of a material, driven by concentration gradients and governed by Fick's laws of diffusion.", "C": "Adsorption is a surface phenomenon where molecules are trapped in surface defects and vacancies, analogous to point defects in crystalline materials.", "D": "Adsorption is the complete wetting of a surface by a liquid, characterized by a contact angle of 0° and governed by Young's equation." }, "correct_answer": "A", "explanation": "Option A correctly defines adsorption as a surface phenomenon involving interactions between surface force fields and adsorbate molecules, with clear distinction between physical and chemical adsorption. Option B incorrectly describes absorption (bulk penetration) rather than surface adsorption. Option C misrepresents adsorption as being solely about defect trapping, ignoring the broader range of surface interactions. Option D confuses adsorption with wetting phenomena, which is a different surface science concept.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1936, "question": "Please write the Burgers vector of the shortest unit dislocation in an FCC crystal", "answer": "FCC: a/2<110>", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求写出FCC晶体中最短单位位错的Burgers矢量，答案需要特定的文字表述（a/2<110>），而不是从选项中选择、判断对错或进行数值计算。 | 知识层次: 题目考查FCC晶体中最短单位位错的Burgers向量的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆FCC晶体中最短单位位错的Burgers向量这一基础定义，无需解释或分析，属于最简单的记忆性知识考察。", "convertible": true, "correct_option": "a/2<110>", "choice_question": "What is the Burgers vector of the shortest unit dislocation in an FCC crystal?", "conversion_reason": "The answer is a standard term in materials science, making it suitable for conversion to a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "a/2<110>", "B": "a<100>", "C": "a/√2<110>", "D": "a/2<111>" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC crystals, the shortest unit dislocation has a Burgers vector of a/2<110>, which represents the shortest perfect lattice translation vector. Option B is incorrect as it represents a full lattice vector but not the shortest possible. Option C is a cognitive bias trap, using the √2 factor which appears in FCC slip systems but is irrelevant for Burgers vector calculation. Option D exploits the intuition that <111> directions are important in FCC, but this is not the correct Burgers vector for dislocations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4311, "question": "What thermodynamic condition must be met for a state of equilibrium to exist?", "answer": "In order for a system to exist in a state of equilibrium the free energy must be a minimum for some specified combination of temperature, pressure, and composition.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释热力学条件，答案提供了详细的文字解释和论述，符合简答题的特征 | 知识层次: 题目考查对热力学平衡状态基本条件的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及热力学平衡的基本概念，但正确选项要求考生不仅要记住自由能的最小化条件，还需要理解这一条件与温度、压力和组成的关联。这超出了简单的定义记忆（等级1），但尚未达到需要阐述复杂概念体系的程度（等级3）。", "convertible": true, "correct_option": "In order for a system to exist in a state of equilibrium the free energy must be a minimum for some specified combination of temperature, pressure, and composition.", "choice_question": "What thermodynamic condition must be met for a state of equilibrium to exist?", "conversion_reason": "The answer is a standard concept in thermodynamics, making it suitable for conversion to a multiple-choice format where the correct option is the provided answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The chemical potentials of all components must be equal across phases", "B": "The system must satisfy both the first and second laws of thermodynamics simultaneously", "C": "The entropy of the system must be maximized at constant internal energy", "D": "The Gibbs free energy must be minimized for given temperature and pressure conditions" }, "correct_answer": "D", "explanation": "The correct answer is D because thermodynamic equilibrium is defined by minimization of Gibbs free energy for given T,P conditions. Option A is a common misconception - while chemical potentials equalize at equilibrium, this is a consequence not the defining condition. Option B exploits intuitive appeal of fundamental laws but is insufficiently specific. Option C describes an entropy maximization condition that only applies to isolated systems, not the more general case of systems interacting with their environment.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1761, "question": "The reason why a base-centered lattice cannot exist in the cubic system is _(9)", "answer": "If a base-centered lattice existed in the cubic system, the characteristic 4L3 symmetry of the cubic system would no longer exist, which does not conform to the symmetry characteristics of the cubic system", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么在立方晶系中不能存在底心点阵，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释为什么底心立方晶系不存在，需要理解立方晶系的对称性特征（4L3对称性）以及底心晶格对对称性的影响。这涉及到对晶体学对称性和晶格类型的综合分析，需要推理和解释机理，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解立方晶系的基本对称性特征（4L3对称性），还需要进行复杂的推理分析，解释为什么底心点阵在立方晶系中无法存在。这涉及到对晶体学对称性原理的深度理解和综合运用，远超简单的记忆或概念辨析。正确选项的推导需要考生将对称性原理与点阵类型的具体限制相结合，属于复杂现象全面分析的范畴。", "convertible": true, "correct_option": "If a base-centered lattice existed in the cubic system, the characteristic 4L3 symmetry of the cubic system would no longer exist, which does not conform to the symmetry characteristics of the cubic system", "choice_question": "The reason why a base-centered lattice cannot exist in the cubic system is:", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The base-centered arrangement would destroy the cubic system's characteristic 4L3 symmetry", "B": "Base-centering would create unequal lattice parameters (a≠b≠c) in the cubic system", "C": "The coordination number of atoms would become inconsistent in a base-centered cubic lattice", "D": "Base-centering would violate the minimum atom packing efficiency requirement for cubic systems" }, "correct_answer": "A", "explanation": "The correct answer is A because the 4L3 symmetry (four 3-fold rotation axes) is the defining characteristic of cubic systems, and base-centering would eliminate this symmetry. Option B is a cognitive bias trap - while unequal parameters would violate cubic symmetry, base-centering alone doesn't necessarily cause this. Option C exploits professional intuition about coordination number changes, but this isn't the fundamental reason. Option D uses a plausible-sounding but non-existent 'packing efficiency requirement' rule to mislead.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4630, "question": "Potassium iodide (KI) exhibits predominantly ionic bonding. The K+ ion has an electron structure that is identical to which inert gas?", "answer": "The K+ ion is just a potassium atom that has lost one electron; therefore, it has an electron configuration the same as argon.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释K+离子的电子结构与哪种惰性气体相同，答案需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查对离子电子结构的基本概念记忆和理解，只需知道钾离子失去一个电子后的电子排布与氩原子相同即可回答，不涉及复杂分析或应用。 | 难度: 该题目属于基础概念记忆类型，仅需识别K+离子的电子构型与哪种惰性气体相同。正确选项直接给出了答案，无需复杂推理或概念间的比较分析，符合选择题型中最简单的难度等级。", "convertible": true, "correct_option": "argon", "choice_question": "Potassium iodide (KI) exhibits predominantly ionic bonding. The K+ ion has an electron structure that is identical to which inert gas?", "conversion_reason": "The answer is a standard term (argon) which can be presented as a choice among other inert gases.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "argon", "B": "neon", "C": "krypton", "D": "xenon" }, "correct_answer": "A", "explanation": "The correct answer is A (argon) because the K+ ion, having lost one electron, has the same electron configuration as argon (1s² 2s² 2p⁶ 3s² 3p⁶). Option B (neon) is a cognitive bias trap, as it's the next lighter noble gas and might seem plausible at first glance. Option C (krypton) is a professional intuition trap, as it's in the same group but heavier, appealing to those who might think 'higher period same group'. Option D (xenon) is a multi-level verification trap, as it's two periods below and might seem correct if considering isoelectronic series without proper analysis.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2911, "question": "For an Al-Cu alloy with an atomic fraction of Cu at 4.6%, after solution treatment at 550°C, the α phase contains x(Cu)=2%. When reheated to 100°C and held for a period, the precipitated θ phase spreads throughout the entire alloy volume. The θ phase has an fcc structure with r=0.143nm, and the average spacing between θ particles is 5nm. If the Cu atoms in the α phase can be neglected after θ precipitation, how many Cu atoms does each θ particle contain?", "answer": "The fcc structure has 4 atoms per unit cell, a=4r/√2=4×0.143/√2=0.404nm. Since x(Cu)=2%, the number of Cu atoms per cm³=0.02×4/(4.04×10⁻⁸)³=1.213×10²¹ atoms/cm³. Therefore, the number of Cu atoms per θ phase particle=1.213×10²¹/8×10¹⁸=151.6 atoms/particle", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，包括计算单位晶胞中的原子数、铜原子浓度、以及每个θ相粒子中的铜原子数。答案给出了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，包括固溶体成分计算、晶体结构参数计算、原子间距与体积关系等综合分析。虽然不需要复杂的推理分析或机理解释，但需要将多个知识点结合起来进行计算和判断。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如fcc结构、原子分数、相变等）并进行多步计算（包括单位转换、体积计算、原子数量估算等）。虽然题目提供了部分计算步骤，但综合分析要求较高，涉及多个知识点的关联应用。", "convertible": true, "correct_option": "151.6 atoms/particle", "choice_question": "For an Al-Cu alloy with an atomic fraction of Cu at 4.6%, after solution treatment at 550°C, the α phase contains x(Cu)=2%. When reheated to 100°C and held for a period, the precipitated θ phase spreads throughout the entire alloy volume. The θ phase has an fcc structure with r=0.143nm, and the average spacing between θ particles is 5nm. If the Cu atoms in the α phase can be neglected after θ precipitation, how many Cu atoms does each θ particle contain?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "151.6 atoms/particle", "B": "75.8 atoms/particle", "C": "303.2 atoms/particle", "D": "227.4 atoms/particle" }, "correct_answer": "A", "explanation": "The correct answer is A (151.6 atoms/particle) based on calculating the volume fraction of θ phase and the number of Cu atoms per unit cell in the fcc structure. Option B is a half-correct value that might arise from neglecting the full precipitation process. Option C doubles the correct value, exploiting a common calculation error in atomic packing. Option D is designed to trap those who incorrectly consider the atomic radius ratio between Al and Cu.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 690, "question": "Most solid-phase reactions are controlled by diffusion rates", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（用×表示错误），符合判断题的特征 | 知识层次: 题目考查对固相反应控制机制这一基础概念的记忆和理解，属于基本原理的记忆性知识 | 难度: 该题目属于基础概念正误判断题，仅需记忆\"大多数固相反应由扩散速率控制\"这一基本原理即可作答。在选择题型中，这类直接考察定义和基本原理记忆的题目属于最简单的难度等级，不需要复杂的分析或推理过程。", "convertible": true, "correct_option": "×", "choice_question": "Most solid-phase reactions are controlled by diffusion rates", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All solid-phase reactions at temperatures below 0.5Tm (where Tm is the melting point) are primarily controlled by interfacial reaction rates rather than diffusion", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While interfacial reactions often dominate at very low temperatures (below 0.3Tm), in the range of 0.3-0.5Tm there can be a transition where both diffusion and interfacial reactions play significant roles. The statement incorrectly generalizes for the entire range below 0.5Tm. Additionally, some systems may still show diffusion control even below 0.3Tm depending on defect concentrations and other factors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 344, "question": "(Taking the face-centered cubic unit cell as an example) What are the common parameters used to describe the characteristics of a crystal structure (unit cell)? How many atoms are there in an FCC unit cell?", "answer": "The number of atoms in an FCC unit cell is 4.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释晶体结构（晶胞）的常见参数，并需要文字论述FCC晶胞中的原子数量，答案形式为简短的文字解释而非计算或选择。 | 知识层次: 题目考查对晶体结构基本参数和面心立方晶胞原子数的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对FCC晶胞中原子数目的基础记忆，属于最基本的概念性知识，无需任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "4", "choice_question": "How many atoms are there in an FCC unit cell?", "conversion_reason": "The answer to the question is a specific numerical value, which can be easily converted into a multiple-choice format with the correct option being '4'.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项B", "B": "选项D", "C": "选项C", "D": "4" }, "correct_answer": "D", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 4060, "question": "Select T/F for the following statement regarding aluminum / aluminum alloys: The relatively low melting point of aluminum is often considered a significant limitation for structural applications.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（Select T/F），答案也是简单的T/F形式，符合判断题的特征。 | 知识层次: 题目考查对铝及其合金基本特性的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念正误判断题，仅需记忆铝及其合金的基本特性（如相对较低的熔点）即可作答。在选择题型中属于最简单的难度等级，不涉及概念理解或复杂分析。", "convertible": true, "correct_option": "T", "choice_question": "Select T/F for the following statement regarding aluminum / aluminum alloys: The relatively low melting point of aluminum is often considered a significant limitation for structural applications.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All aluminum alloys exhibit superior corrosion resistance compared to pure aluminum in all environmental conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many aluminum alloys are designed to enhance specific properties, not all exhibit superior corrosion resistance compared to pure aluminum. Pure aluminum forms a protective oxide layer that provides excellent corrosion resistance. Some alloys may sacrifice corrosion resistance for other properties like strength. Additionally, performance varies significantly depending on the specific environmental conditions (e.g., saltwater vs. acidic environments). The absolute terms 'all' and 'in all conditions' make this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3335, "question": "After quenching T8 steel wire to 550°C and holding for 1s, indicate its phase and composition.", "answer": "B⊥[F(w_C=0.0218%)+Fe3C(w_C=6.69%)]", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出材料的相和组成，需要文字解释和论述，答案形式为相组成的具体描述而非选择或计算 | 知识层次: 题目需要结合钢的相变知识和TTT曲线，通过中等复杂度的分析判断在特定温度和时间下的相组成和成分。这涉及多步概念关联和综合分析，但不需要复杂的机理推导或创新设计。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握T8钢的相变知识，包括淬火后的相组成和成分计算。虽然题目给出了具体的温度和时间条件，但需要考生能够正确识别相组成（F+Fe3C）并计算其成分（w_C=0.0218%和w_C=6.69%）。这需要考生具备中等应用层次的知识，能够进行多步计算和概念关联，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "B⊥[F(w_C=0.0218%)+Fe3C(w_C=6.69%)]", "choice_question": "After quenching T8 steel wire to 550°C and holding for 1s, what is its phase and composition?", "conversion_reason": "The answer is a standard term or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Austenite (γ-Fe) with 0.8% C", "B": "Pearlite (α-Fe + Fe3C) with 0.8% C", "C": "Bainite (α-Fe + Fe3C) with 0.8% C", "D": "Martensite with 0.8% C" }, "correct_answer": "C", "explanation": "Correct answer is C because at 550°C for 1s, T8 steel undergoes bainitic transformation forming bainite (α-Fe + Fe3C) with the original 0.8% C composition. Option A is incorrect because austenite is unstable at this temperature. Option B is a common misconception as pearlite requires slower cooling. Option D exploits the AI's tendency to associate quenching with martensite, ignoring the specific temperature hold.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1201, "question": "What kind of motion can a screw dislocation undergo?", "answer": "Slip", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释螺丝位错可以进行的运动类型，答案需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查对位错运动类型的基础概念记忆，仅需回答\"滑移\"这一基本定义，无需深入分析或综合应用。 | 难度: 该题目属于基础概念记忆类型，仅需考生回忆并识别\"螺旋位错\"的基本运动方式。在选择题型中，这种直接考查定义或分类的题目属于最简单的等级1难度，不需要解释或分析过程。", "convertible": true, "correct_option": "Slip", "choice_question": "What kind of motion can a screw dislocation undergo?", "conversion_reason": "The answer is a standard term in the field, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip", "B": "Climb", "C": "Cross-slip", "D": "Twist" }, "correct_answer": "A", "explanation": "The correct answer is A because a screw dislocation can only undergo slip motion along its Burgers vector direction. Option B (Climb) is incorrect as it requires diffusion of vacancies/interstitials which screw dislocations cannot do. Option C (Cross-slip) is a plausible but incorrect answer as it's a specific case of slip that only occurs under certain conditions. Option D (Twist) is designed to exploit confusion between dislocation motion and crystal twinning mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2071, "question": "Point out the errors in the following concepts and correct them: (13) When studying the process of refining grains in a certain metal, the main focus is to find nucleating agents with low melting points and lattice constants similar to those of the metal, as their nucleation catalytic efficiency is the highest.", "answer": "The main focus is to find those with high melting points, and.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求指出并纠正错误概念，这类似于判断题中判断陈述的对错并给出正确解释。答案部分直接指出了原陈述中的错误并提供了正确的表述，符合判断题的特征。 | 知识层次: 题目考查对晶粒细化过程中形核剂选择的基本概念的理解和记忆，属于基础概念范畴。 | 难度: 在选择题型中，这道题目属于中等难度。虽然考察的是基础概念记忆（晶粒细化过程中的形核剂选择标准），但需要考生不仅记住正确概念（高熔点），还要能够识别并纠正题目中给出的错误概念（低熔点）。这比单纯的正误判断（等级1）要求更高，但不需要进行复杂概念分析（等级3）。", "convertible": true, "correct_option": "The main focus is to find those with high melting points, and.", "choice_question": "Point out the errors in the following concepts and correct them: (13) When studying the process of refining grains in a certain metal, the main focus is to find nucleating agents with low melting points and lattice constants similar to those of the metal, as their nucleation catalytic efficiency is the highest.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In grain refinement of metals, nucleating agents with lattice constants exactly matching the base metal always exhibit the highest catalytic efficiency regardless of their melting points.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While lattice matching is important, the statement incorrectly uses 'always' and ignores the critical role of high melting points in maintaining structural stability during nucleation. Optimal agents require both lattice matching AND high melting points, making this absolute statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4618, "question": "What are the characteristics of transparent materials in terms of their appearance and light transmittance?", "answer": "Virtually all of the incident light is transmitted through transparent materials, and one can see clearly through them.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释透明材料的外观和透光特性，答案需要文字论述而非选择、判断或计算。 | 知识层次: 题目考查透明材料的基本特性（外观和透光率）的记忆和理解，属于基础概念记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接考察透明材料的基本特性（外观和透光率），正确选项是对透明材料定义的直接陈述，不需要任何解释或复杂推理。学生只需记住透明材料的定义特征即可正确作答，属于最基础的概念记忆层次。", "convertible": true, "correct_option": "Virtually all of the incident light is transmitted through transparent materials, and one can see clearly through them.", "choice_question": "Which of the following best describes the characteristics of transparent materials in terms of their appearance and light transmittance?", "conversion_reason": "The answer is a standard description of the characteristics of transparent materials, which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Virtually all of the incident light is transmitted through transparent materials, and one can see clearly through them.", "B": "Transparent materials exhibit total internal reflection when the angle of incidence exceeds the critical angle, making them appear opaque under certain conditions.", "C": "The refractive index of transparent materials must be exactly 1.0 to achieve perfect light transmission without any scattering.", "D": "Transparent materials absorb all wavelengths of visible light equally, resulting in their colorless appearance." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the fundamental characteristics of transparent materials, where most incident light is transmitted allowing clear visibility. Option B exploits cognitive bias by mixing truth (total internal reflection) with false conclusion (appearing opaque). Option C is a professional intuition trap using a plausible-sounding but impossible refractive index value. Option D creates a multi-level verification trap by combining correct observation (colorless) with incorrect mechanism (equal absorption).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4342, "question": "Consider 2.0 kg of a 99.6 wt % Fe-0.4 wt % C alloy that is cooled to a temperature just below the eutectoid. How many kilograms of cementite form?", "answer": "0.114 kg of cementite forms.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定在特定条件下形成的碳化铁（cementite）的质量。答案给出了具体的计算结果（0.114 kg），这表明解答过程涉及到了材料科学中的相图分析和质量平衡计算。 | 知识层次: 题目需要进行多步计算，涉及合金成分分析、相图应用和相组成计算，需要综合运用材料科学中的相变知识和公式应用，但不需要复杂的推理或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解相图概念、杠杆定律应用以及多步计算过程。题目涉及合金成分分析、相变温度判断和定量计算，虽然选项已给出正确答案，但仍需综合运用多个知识点才能验证正确性。", "convertible": true, "correct_option": "0.114 kg of cementite forms", "choice_question": "Consider 2.0 kg of a 99.6 wt % Fe-0.4 wt % C alloy that is cooled to a temperature just below the eutectoid. How many kilograms of cementite form?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.114 kg", "B": "0.228 kg", "C": "0.057 kg", "D": "0.400 kg" }, "correct_answer": "A", "explanation": "The correct answer is A (0.114 kg) calculated using the lever rule at the eutectoid composition (0.76 wt% C). Option B (0.228 kg) doubles the correct value, exploiting the common error of not accounting for the alloy's initial carbon content being below eutectoid. Option C (0.057 kg) halves the correct answer, targeting those who might incorrectly divide by the total mass. Option D (0.400 kg) directly uses the alloy's carbon percentage, a tempting but fundamentally flawed approach that ignores phase diagram analysis.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 462, "question": "Screw dislocation", "answer": "A dislocation where the dislocation line is parallel to the Burgers vector.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Screw dislocation\"进行文字解释和论述，答案是一个定义性的描述，符合简答题的特征。 | 知识层次: 题目考查对screw dislocation这一基本概念的定义记忆和理解，属于材料科学中位错理论的基础知识，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别螺型位错的基本定义（位错线与伯氏矢量平行），属于最基础的概念记忆层次，无需复杂分析或推理步骤。", "convertible": true, "correct_option": "A dislocation where the dislocation line is parallel to the Burgers vector.", "choice_question": "Which of the following best describes a screw dislocation?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct answer as one of the options and creating plausible distractors for the other options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A dislocation where the dislocation line is parallel to the Burgers vector", "B": "A defect where atomic planes spiral around the dislocation line like a screw thread", "C": "A linear defect where the Burgers vector is perpendicular to the dislocation line", "D": "A type of dislocation that only occurs in BCC crystal structures" }, "correct_answer": "A", "explanation": "The correct answer is A because a screw dislocation is fundamentally defined by the parallel relationship between the dislocation line and Burgers vector. Option B is a cognitive bias trap - while it describes the visual appearance, it's not the rigorous definition. Option C reverses the key relationship (it describes edge dislocation). Option D is a professional intuition trap - screw dislocations occur in all crystal structures, not just BCC.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1194, "question": "The typical crystal structures of metals are (1), (2), and (3)", "answer": "(1) body-centered cubic; (2) face-centered cubic; (3) close-packed hexagonal", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写金属的典型晶体结构名称，答案需要以文字形式提供具体结构名称，属于简答题类型 | 知识层次: 题目考查金属典型晶体结构的基础概念记忆，仅需回忆和列举三种常见结构类型，不涉及应用或分析。 | 难度: 该题目属于基础概念记忆类型，仅需回忆金属的三种典型晶体结构名称（体心立方、面心立方和密排六方）。在选择题型中，这种直接考察定义或分类的记忆性知识属于最低难度等级，无需解释或分析步骤。", "convertible": true, "correct_option": "body-centered cubic; face-centered cubic; close-packed hexagonal", "choice_question": "The typical crystal structures of metals are:", "conversion_reason": "The answer is a standard set of terms that can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "body-centered cubic; face-centered cubic; close-packed hexagonal", "B": "body-centered cubic; face-centered cubic; diamond cubic", "C": "face-centered cubic; close-packed hexagonal; perovskite", "D": "body-centered cubic; simple cubic; zinc blende" }, "correct_answer": "A", "explanation": "正确答案A包含了金属最常见的三种晶体结构：体心立方（bcc）、面心立方（fcc）和密排六方（hcp）。干扰项B中的金刚石立方结构主要出现在半导体材料如硅中；干扰项C中的钙钛矿结构主要出现在氧化物材料中；干扰项D中的闪锌矿结构主要出现在II-VI族化合物半导体中。这些干扰项利用了材料科学中常见的晶体结构混淆，特别是那些在半导体或陶瓷材料中常见但在金属中极少出现的结构。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2896, "question": "Calculate the relative amounts (in mol%) of monoclinic ZrO2 solid solution (Monoclinic ZrO2 SS) and cubic ZrO2 solid solution (Cubic ZrO2 SS) at room temperature for a CaO–ZrO2 ceramic with w(CaO)=4%. Assume that the solubilities of monoclinic ZrO2 solid solution and cubic ZrO2 solid solution at room temperature are 2mol% CaO and 15mol% CaO, respectively.", "answer": "Using the conversion formula between mole fraction and mass fraction, the mole fraction corresponding to w(Ca)=4% can be calculated: xA = (wA/ArA)/(wA/ArA + wB/ArB) = (4/(40+16))/(4/(40+16) + 96/(91+16×2)) ≈ 0.08; thus, 4wt% CaO = 8mol% CaO. Moreover, it can be observed from the figure that the solubility limit changes little below 900°C, yielding: monoclinic phase % = (xcub - x)/(xcub - xmono) × 100% = (15 - 8)/(15 - 2) × 100% = 53.8%; cubic phase % = (x - xmono)/(xcub - xmono) × 100% = (8 - 2)/(15 - 2) × 100% = 46.2%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及摩尔百分比的计算和相图分析，答案展示了具体的计算步骤和结果。 | 知识层次: 题目需要进行多步计算，包括摩尔分数转换和相组成计算，涉及对相图的理解和公式应用，需要综合分析不同相在特定条件下的溶解度限制。虽然不涉及复杂的机理分析或创新设计，但超出了简单应用的范围，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要完成多步骤计算（包括摩尔分数转换和相比例计算），同时需要理解溶解度限和相图概念。虽然题目提供了关键参数，但解题过程涉及多个公式的综合应用和逻辑推导，对考生的计算能力和概念关联能力有较高要求。", "convertible": true, "correct_option": "53.8% monoclinic ZrO2 SS and 46.2% cubic ZrO2 SS", "choice_question": "For a CaO–ZrO2 ceramic with w(CaO)=4%, calculate the relative amounts (in mol%) of monoclinic ZrO2 solid solution (Monoclinic ZrO2 SS) and cubic ZrO2 solid solution (Cubic ZrO2 SS) at room temperature, given the solubilities of monoclinic ZrO2 solid solution and cubic ZrO2 solid solution at room temperature are 2mol% CaO and 15mol% CaO, respectively.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "53.8% monoclinic ZrO2 SS and 46.2% cubic ZrO2 SS", "B": "46.2% monoclinic ZrO2 SS and 53.8% cubic ZrO2 SS", "C": "80% monoclinic ZrO2 SS and 20% cubic ZrO2 SS", "D": "20% monoclinic ZrO2 SS and 80% cubic ZrO2 SS" }, "correct_answer": "A", "explanation": "The correct answer is derived using the lever rule in phase diagrams. For a composition of 4% CaO, the relative amounts are calculated as (15-4)/(15-2)=0.846 for monoclinic and (4-2)/(15-2)=0.154 for cubic, which when normalized gives 53.8% and 46.2% respectively. Option B reverses these percentages, exploiting the common mistake of misapplying the lever rule. Option C represents a naive assumption that most ZrO2 would remain in the monoclinic phase, while Option D represents the opposite extreme assumption favoring the cubic phase due to its higher solubility limit, both ignoring the precise calculation required.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1820, "question": "When selecting the unit parallelepiped of a space lattice, the primary principle is _ (3)", "answer": "(3) The symmetry of the unit parallelepiped should conform to the symmetry of the entire space lattice", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个空格，答案是一个完整的句子解释，需要文字解释和论述，而不是从多个选项中选择或简单的对错判断或数值计算。 | 知识层次: 题目考查对空间晶格单位平行六面体选择原则的基本概念记忆和理解，属于晶体学基础原理的范畴。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需回忆并选择关于空间晶格单位平行六面体选择的基本原则。正确选项直接给出了定义性的陈述，无需进行复杂的分析或推理，符合等级1的基本定义简答难度标准。", "convertible": true, "correct_option": "The symmetry of the unit parallelepiped should conform to the symmetry of the entire space lattice", "choice_question": "When selecting the unit parallelepiped of a space lattice, the primary principle is:", "conversion_reason": "The answer is a standard concept or principle, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The symmetry of the unit parallelepiped should conform to the symmetry of the entire space lattice", "B": "The unit parallelepiped should contain the minimum number of lattice points", "C": "The edges of the unit parallelepiped must coincide with crystallographic axes", "D": "The volume of the unit parallelepiped should be minimized for computational efficiency" }, "correct_answer": "A", "explanation": "The correct answer is A because the fundamental principle in selecting a unit cell is to preserve the full symmetry of the crystal system. Option B is incorrect because while primitive cells have minimum lattice points, they don't always show the full symmetry. Option C is a common misconception - crystallographic axes can be non-orthogonal and don't necessarily define the unit cell edges. Option D is a computational bias that contradicts actual crystallographic practice where symmetry takes precedence over volume minimization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4768, "question": "What is the first criterion upon which factors of safety are based?", "answer": "The first criterion is consequences of failure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述来回答问题，答案是一个简短的陈述，而不是从多个选项中选择或进行数值计算。 | 知识层次: 题目考查安全系数基本准则的记忆和理解，属于基础概念层次 | 难度: 在选择题型中，此题仅考察对基础定义的记忆，属于最简单的难度等级。题目直接询问安全系数的首要标准，正确选项明确给出了\"失效后果\"这一基本定义，不需要任何解释或分析步骤。学生只需记住这个基础概念即可正确作答，符合选择题型中最基础的知识点掌握要求。", "convertible": true, "correct_option": "The first criterion is consequences of failure.", "choice_question": "What is the first criterion upon which factors of safety are based?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Consequences of failure", "B": "Material yield strength", "C": "Expected service conditions", "D": "Manufacturing tolerances" }, "correct_answer": "A", "explanation": "The correct answer is A because factors of safety are primarily determined by the potential consequences of failure (human safety, environmental impact, etc.). B is a strong distractor as yield strength is fundamental in material selection but not the first criterion. C exploits the intuition that service conditions should be considered first, while D targets the common focus on manufacturing precision in materials engineering.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4096, "question": "How are continuous fibers typically oriented in fibrous composites?(a) Aligned(b) Partially oriented(c) Randomly oriented", "answer": "Continuous fibers are typically aligned in fibrous composites.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从三个选项(a)(b)(c)中选择关于纤维复合材料中连续纤维取向方式的正确答案 | 知识层次: 题目考查对纤维复合材料中连续纤维排列方式的基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需识别连续纤维在纤维复合材料中的典型排列方式（对齐）。选项直接对应定义，无需复杂辨析或深度理解，符合等级1的简单概念识别标准。", "convertible": true, "correct_option": "Aligned", "choice_question": "How are continuous fibers typically oriented in fibrous composites?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Aligned along the principal stress direction", "B": "Partially oriented to optimize fracture toughness", "C": "Randomly oriented for isotropic properties", "D": "Orthogonally layered for through-thickness reinforcement" }, "correct_answer": "A", "explanation": "Continuous fibers are typically aligned along the principal stress direction to maximize load-bearing capacity (A). Option B exploits the cognitive bias toward toughness optimization, while C triggers the common misconception about isotropic requirements. Option D uses a valid but contextually incorrect reinforcement strategy for continuous fibers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1430, "question": "Which is the most closely packed plane of a body-centered cubic crystal?", "answer": "110", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个可能的晶体平面中选择最紧密排列的平面，答案\"110\"是其中一个特定选项 | 知识层次: 题目考查对体心立方晶体最密排面的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆体心立方晶体最密排面的定义即可选出正确答案110。不需要进行概念辨析或复杂分析，符合等级1的简单概念识别标准。", "convertible": true, "correct_option": "110", "choice_question": "Which is the most closely packed plane of a body-centered cubic crystal?", "conversion_reason": "The original question is already in a multiple-choice format with a specific correct answer, making it convertible to a single-choice question by simply identifying the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "111", "B": "110", "C": "100", "D": "112" }, "correct_answer": "B", "explanation": "The (110) plane is the most closely packed plane in a body-centered cubic (BCC) crystal structure. This is because it has the highest planar density of atoms. Option A (111) is a common misconception as it is the most closely packed plane in face-centered cubic (FCC) structures, exploiting the cognitive bias of confusing BCC with FCC. Option C (100) appears simpler and more symmetric, appealing to intuitive but incorrect selection. Option D (112) is a less common plane that might seem plausible due to its intermediate Miller indices, creating a verification trap for those not thoroughly familiar with BCC packing.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4402, "question": "Cite disadvantages of hot working.", "answer": "The disadvantages of hot working are: (1) A poor surface finish. (2) A variety of mechanical properties is not possible.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举热加工的缺点，答案以文字解释和论述的形式给出，没有提供选项或要求计算，符合简答题的特征。 | 知识层次: 题目考查对热加工缺点的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列举热加工的缺点，但只需要记忆两个具体的缺点（表面光洁度差和机械性能多样性受限），不需要进行复杂的分析或比较。这属于基础概念记忆的范畴，但比简单的定义记忆稍微复杂一些，因为需要记住多个相关点。", "convertible": true, "correct_option": "A poor surface finish and a variety of mechanical properties is not possible.", "choice_question": "Which of the following are disadvantages of hot working?", "conversion_reason": "The answer provided is a standard list of disadvantages, which can be formatted into a multiple-choice question by presenting these points as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Poor surface finish and inability to achieve uniform mechanical properties", "B": "Increased grain growth and reduced yield strength due to recrystallization", "C": "Higher energy consumption compared to cold working processes", "D": "Limited dimensional accuracy caused by thermal contraction during cooling" }, "correct_answer": "A", "explanation": "Correct answer A identifies the fundamental limitations of hot working where high temperatures prevent good surface finish and uniform properties. Option B is a cognitive bias trap - while grain growth occurs, yield strength actually decreases (not increases) with recrystallization. Option C exploits professional intuition by presenting a seemingly logical energy comparison that ignores hot working's lower deformation energy requirements. Option D is a multi-level verification trap where thermal contraction is real but dimensional accuracy is primarily controlled by tooling, not cooling.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2145, "question": "Point out the error in the following concept: (2) Because the direction of each jump of solid atoms is random, the diffusion flux is zero under any circumstances.", "answer": "The direction of each jump of atoms is random. Only when the system is in thermal equilibrium, the probability of atoms jumping in any direction is equal. At this time, although there is atomic migration (i.e., diffusion), there is no macroscopic diffusion flow. If the system is in a non-equilibrium state, there must be a gradient of thermodynamic potential in the system (specifically expressed as concentration gradient, chemical potential gradient, strain energy gradient, etc.). The probability of atoms jumping in the direction of decreasing thermodynamic potential will be greater than that in the direction of increasing thermodynamic potential. As a result, macroscopic diffusion flow occurs.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求指出概念中的错误并进行详细的文字解释和论述，答案形式为一段完整的论述性文字，而非选择、判断或计算。 | 知识层次: 题目要求对扩散现象进行深入分析，涉及非平衡态热力学、概率统计和宏观扩散流的关系，需要综合运用多个概念并进行推理分析，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The direction of each jump of atoms is random. Only when the system is in thermal equilibrium, the probability of atoms jumping in any direction is equal. At this time, although there is atomic migration (i.e., diffusion), there is no macroscopic diffusion flow. If the system is in a non-equilibrium state, there must be a gradient of thermodynamic potential in the system (specifically expressed as concentration gradient, chemical potential gradient, strain energy gradient, etc.). The probability of atoms jumping in the direction of decreasing thermodynamic potential will be greater than that in the direction of increasing thermodynamic potential. As a result, macroscopic diffusion flow occurs.", "choice_question": "Which of the following correctly explains the error in the concept: 'Because the direction of each jump of solid atoms is random, the diffusion flux is zero under any circumstances.'?", "conversion_reason": "The original question is a short answer question that requires explaining an error in a given concept. The answer is a detailed and standard explanation, which can be converted into a multiple-choice question by presenting the correct explanation as one of the options. The question can be rephrased to ask for the correct explanation of the error.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The statement ignores the thermodynamic driving forces that create biased atomic jumps in non-equilibrium systems", "B": "Solid state diffusion cannot occur through random jumps due to lattice constraints", "C": "Diffusion flux is always non-zero due to quantum tunneling effects at atomic scales", "D": "The randomness assumption is incorrect as atoms follow predetermined diffusion paths in crystals" }, "correct_answer": "A", "explanation": "Correct answer A addresses the key error by highlighting the thermodynamic potential gradients that create directional bias in non-equilibrium systems. Distractor B exploits the common misconception that lattice structure prevents random jumps. Distractor C introduces an advanced but irrelevant quantum effect to mislead models familiar with nanoscale phenomena. Distractor D appeals to the false intuition that crystalline order must dictate diffusion paths, a common oversimplification in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3, "question": "According to the nature of bonding forces, what are the types of bonding interactions in crystals?", "answer": "The bonding interactions in crystals can be classified into ionic bonds, covalent bonds, metallic bonds, van der Waals bonds, and hydrogen bonds.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据键合力的性质分类晶体中的键合相互作用，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查晶体中键合相互作用的基本分类，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需要识别晶体中键合作用的基本分类（离子键、共价键、金属键、范德华力和氢键）。题目不涉及概念解释或复杂体系阐述，仅考察对定义性知识的直接回忆，因此属于最低难度等级。", "convertible": true, "correct_option": "The bonding interactions in crystals can be classified into ionic bonds, covalent bonds, metallic bonds, van der Waals bonds, and hydrogen bonds.", "choice_question": "According to the nature of bonding forces, which of the following correctly describes the types of bonding interactions in crystals?", "conversion_reason": "The answer is a standard classification of bonding interactions in crystals, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ionic, covalent, metallic, and van der Waals bonds only", "B": "Primary bonds (ionic, covalent, metallic) and secondary bonds (hydrogen, dipole-dipole)", "C": "Strong bonds (ionic, covalent, metallic) and weak interactions (van der Waals, hydrogen bonding)", "D": "Ionic bonds, covalent bonds, metallic bonds, van der Waals bonds, and hydrogen bonds" }, "correct_answer": "D", "explanation": "The correct answer D comprehensively includes all major types of bonding interactions in crystals. Option A is missing hydrogen bonds, which are crucial in many crystalline materials like ice. Option B incorrectly classifies hydrogen bonds as dipole-dipole interactions and omits van der Waals forces. Option C's classification is conceptually problematic as hydrogen bonds are intermediate in strength and don't fit neatly into either category. Advanced AI might be misled by oversimplified classifications in options A-C that appear plausible at first glance but fail to account for the full spectrum of bonding interactions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1257, "question": "What is annealing twin? Explain its formation mechanism.", "answer": "Annealing twin is a type of twin, which refers to the formation of lamellar twins with straight interfaces inside grains after cold deformation and recrystallization annealing in certain face-centered cubic metals, such as Cu, Ni, nickel alloys, and austenitic steels. These twin interfaces are on the {111} planes. Since they appear only after annealing, they are called annealing twins.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释\"annealing twin\"的定义和形成机制，需要详细的文字解释和论述，而不是选择、判断或计算。答案也提供了详细的描述性回答，符合简答题的特征。 | 知识层次: 题目考查对\"退火孪晶\"这一基本概念的定义及其形成机制的记忆和理解，属于材料科学中的基础概念性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目要求考生不仅知道\"annealing twin\"的基本定义，还需要理解其形成机制和典型材料。这属于概念解释和描述的层次，比单纯记忆定义（等级1）要求更高，但不需要复杂的概念体系阐述（等级3）。题目给出了完整的正确选项，考生需要识别和匹配这些关键信息点。", "convertible": true, "correct_option": "Annealing twin is a type of twin, which refers to the formation of lamellar twins with straight interfaces inside grains after cold deformation and recrystallization annealing in certain face-centered cubic metals, such as Cu, Ni, nickel alloys, and austenitic steels. These twin interfaces are on the {111} planes. Since they appear only after annealing, they are called annealing twins.", "choice_question": "Which of the following best describes annealing twin and its formation mechanism?", "conversion_reason": "The answer is a standard definition and explanation of a concept, which can be converted into a multiple-choice question format by providing the correct answer as one of the options and creating plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Annealing twins are lamellar twins with straight {111} interfaces formed during recrystallization annealing of cold-worked FCC metals like Cu and Ni", "B": "Annealing twins are deformation-induced twins that form during cold working of BCC metals like Fe and W", "C": "Annealing twins are curved twin boundaries formed during grain growth in HCP metals like Mg and Zn", "D": "Annealing twins are stacking faults created during rapid quenching of austenitic steels" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes annealing twins as lamellar twins with straight {111} interfaces formed during recrystallization of cold-worked FCC metals. Option B incorrectly associates annealing twins with BCC metals and deformation. Option C wrongly describes curved boundaries in HCP metals. Option D confuses twins with stacking faults and rapid quenching.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3305, "question": "Compare the mechanical properties of upper bainite and lower bainite", "answer": "Generally, the hardness and strength of lower bainite are higher than those of upper bainite, and the plasticity and toughness of lower bainite are also higher than those of upper bainite. Lower bainite has good comprehensive mechanical properties and better toughness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较上贝氏体和下贝氏体的力学性能，需要文字解释和论述，而不是选择、判断或计算。答案提供了详细的文字描述，符合简答题的特征。 | 知识层次: 题目要求比较上贝氏体和下贝氏体的力学性能，需要理解两种组织的形成机制及其对性能的影响，涉及多个概念的关联和综合分析，但不需要深入机理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解并比较上下贝氏体的机械性能差异，包括硬度、强度、塑性和韧性等综合性能的分析。虽然不涉及复杂的计算，但需要对材料微观组织与性能的关系有较深入的理解。", "convertible": true, "correct_option": "Generally, the hardness and strength of lower bainite are higher than those of upper bainite, and the plasticity and toughness of lower bainite are also higher than those of upper bainite. Lower bainite has good comprehensive mechanical properties and better toughness.", "choice_question": "Which of the following statements correctly compares the mechanical properties of upper bainite and lower bainite?", "conversion_reason": "The answer is a standard comparison of mechanical properties, which can be rephrased into a multiple-choice format by asking for the correct comparison.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Lower bainite exhibits higher hardness and strength than upper bainite, while maintaining superior toughness due to its finer carbide distribution", "B": "Upper bainite shows greater hardness than lower bainite because its coarse cementite particles provide more effective barriers to dislocation motion", "C": "Both bainite forms have identical strength but lower bainite has better ductility due to its acicular ferrite morphology", "D": "Lower bainite has lower toughness than upper bainite despite higher hardness, as its needle-like structure creates stress concentration points" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual relationship where lower bainite's fine, dispersed carbides enhance both strength and toughness. Option B reverses the hardness relationship and incorrectly attributes strength to coarse carbides. Option C falsely claims equal strength and misattributes ductility to morphology rather than carbide distribution. Option D correctly identifies higher hardness but incorrectly states lower toughness, exploiting the common misconception that harder materials must be less tough.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3765, "question": "A 4-in-diameter sphere of liquid copper is allowed to solidify, producing a spherical shrinkage cavity in the center of the casting. Determine the volume and diameter of the shrinkage cavity in the copper casting.", "answer": "shrinkage volume: 1.709 in.^{3}; diameter of shrinkage cavity: 1.30 in.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算确定收缩腔的体积和直径，答案给出了具体的数值结果，解答过程需要应用材料科学中的相关公式和计算步骤。 | 知识层次: 题目需要进行多步计算，包括体积计算和直径转换，同时需要理解铜凝固过程中的收缩现象及其对铸件的影响。虽然不涉及复杂的机理分析或创新设计，但需要综合运用材料科学中的基本概念和公式进行计算。 | 难度: 在选择题中属于中等偏上难度，需要理解铜凝固过程中的收缩原理，掌握体积收缩率的计算，并能正确应用球体体积公式进行多步推导。虽然题目提供了正确选项减少了计算量，但仍需综合分析材料特性和几何关系才能准确匹配答案。", "convertible": true, "correct_option": "shrinkage volume: 1.709 in.^{3}; diameter of shrinkage cavity: 1.30 in.", "choice_question": "A 4-in-diameter sphere of liquid copper is allowed to solidify, producing a spherical shrinkage cavity in the center of the casting. The volume and diameter of the shrinkage cavity in the copper casting are:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "shrinkage volume: 1.709 in.^{3}; diameter of shrinkage cavity: 1.30 in.", "B": "shrinkage volume: 3.418 in.^{3}; diameter of shrinkage cavity: 1.84 in.", "C": "shrinkage volume: 0.855 in.^{3}; diameter of shrinkage cavity: 1.08 in.", "D": "shrinkage volume: 2.563 in.^{3}; diameter of shrinkage cavity: 1.56 in." }, "correct_answer": "A", "explanation": "The correct answer accounts for the 6% volumetric shrinkage of copper during solidification. Option B doubles the correct shrinkage volume, exploiting the common error of misapplying linear shrinkage (4.5%) to volume calculations. Option C halves the correct volume, targeting those who confuse solidification shrinkage with thermal contraction. Option D uses a 9% shrinkage rate, a plausible but incorrect value for some alloys, creating confusion between pure copper and copper alloys.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4831, "question": "What is the distinction between electronic and ionic conduction? \\\\", "answer": "When a current arises from a flow of electrons, the conduction is termed electronic; for \\\\ ionic conduction, the current results from the net motion of charged ions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释电子传导和离子传导的区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查电子传导和离子传导的基本定义和区别，属于基础概念的记忆和理解层面，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并区分电子传导和离子传导的基本定义，属于最基础的概念记忆层次。正确选项直接给出了两者的定义对比，不需要进行额外的分析或推理，因此属于难度等级1。", "convertible": true, "correct_option": "When a current arises from a flow of electrons, the conduction is termed electronic; for ionic conduction, the current results from the net motion of charged ions.", "choice_question": "What is the distinction between electronic and ionic conduction?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Electronic conduction involves electron hopping between localized states, while ionic conduction requires mobile vacancies", "B": "Electronic conduction occurs in metals, while ionic conduction is exclusive to liquid electrolytes", "C": "The charge carriers in electronic conduction are always electrons, whereas ionic conduction can involve either cations or anions", "D": "Electronic conduction shows temperature-independent resistivity, while ionic conduction always exhibits Arrhenius behavior" }, "correct_answer": "C", "explanation": "Correct answer C precisely distinguishes the fundamental charge carriers. Distractors employ strategic traps: A mixes up hopping conduction (a special case) with general electronic conduction and incorrectly limits ionic conduction to vacancy mechanism. B exploits the common but incorrect metal/electrolyte dichotomy, ignoring solid-state ionic conductors. D creates a false dichotomy by oversimplifying temperature dependencies, as some electronic conductors show Arrhenius behavior (e.g., semiconductors) while some ionic systems show non-Arrhenius behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4066, "question": "[a] Copper has a higher elastic modulus than aluminum.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（铜的弹性模量比铝高），并要求判断其正确性（答案为T表示正确），这符合判断题的特征 | 知识层次: 题目考查对铜和铝弹性模量这一基本物理性质的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求判断铜和铝的弹性模量高低这一基本概念的正误，属于最基础的概念记忆层次。题目仅涉及单一知识点，无需理解或分析复杂概念，解题步骤简单直接，符合等级1的难度标准。", "convertible": true, "correct_option": "T", "choice_question": "[a] Copper has a higher elastic modulus than aluminum.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit higher hardness than metallic materials at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics are harder than metals, there are exceptions. Some metallic materials like tungsten carbide can exhibit higher hardness than certain soft ceramics. The statement uses an absolute term 'all' which makes it incorrect. This tests understanding of material property ranges and the danger of absolute statements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2111, "question": "Point out the error in the following concept and correct it: In the Fe-Fe3C system alloys, only hypereutectoid steels have secondary cementite in their equilibrium crystallization structure.", "answer": "Only when the iron-carbon alloy with a carbon mass fraction of 0.0077 < w_c < 0.043 undergoes equilibrium crystallization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择或判断 | 知识层次: 题目要求识别并纠正Fe-Fe3C系统中关于二次渗碳体形成的错误概念，需要理解不同碳含量范围内合金的平衡结晶结构，并能够将这一概念应用到具体情境中。这涉及到多步分析和概念关联，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅要理解Fe-Fe3C相图的基本概念，还需要能够区分不同碳含量范围内的合金特性，并准确识别原陈述中的错误。解题过程涉及：", "convertible": true, "correct_option": "Only when the iron-carbon alloy with a carbon mass fraction of 0.0077 < w_c < 0.043 undergoes equilibrium crystallization.", "choice_question": "Which of the following statements correctly identifies the error and correction in the concept: 'In the Fe-Fe3C system alloys, only hypereutectoid steels have secondary cementite in their equilibrium crystallization structure.'?", "conversion_reason": "The original question asks to point out and correct an error in a given concept, which can be rephrased into a multiple-choice format by asking which option correctly identifies the error and correction. The answer is a specific statement that can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The statement is incorrect because both hypereutectoid and hypoeutectoid steels can form secondary cementite during equilibrium crystallization.", "B": "The error is in the carbon content range - secondary cementite appears in alloys with 0.0218 < w_c < 0.77, not just hypereutectoid steels.", "C": "Only hypereutectoid steels (w_c > 0.77) form secondary cementite, but it precipitates from austenite, not during equilibrium crystallization.", "D": "The statement is correct as written - only hypereutectoid steels develop secondary cementite in their equilibrium structure." }, "correct_answer": "A", "explanation": "The correct answer is A because secondary cementite can form in both hypereutectoid steels (from austenite) and hypoeutectoid steels (from ferrite) during equilibrium cooling. Option B uses a plausible but incorrect carbon range (0.0218 is the solubility limit of C in ferrite at 727°C). Option C correctly identifies the precipitation source but incorrectly limits it to hypereutectoid steels. Option D reinforces the original misconception. Advanced AIs might choose B due to its numerical specificity or C due to partial correctness about precipitation sources.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1616, "question": "The _（3）__ of an atom or ion refers to the number of atoms directly adjacent to it in the crystal structure or the number of all hetero-ions combined with it.", "answer": "（3）coordination number", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（coordination number），属于需要简短文字回答的类型，而不是从选项中选择或判断对错。 | 知识层次: 题目考查的是\"配位数\"这一基本概念的定义和记忆，属于材料科学中最基础的概念之一，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即\"coordination number\"的定义。学生只需识别并选择正确的术语填空，无需进行概念解释或复杂分析。这属于最基本的选择题难度等级。", "convertible": true, "correct_option": "coordination number", "choice_question": "The _（3）__ of an atom or ion refers to the number of atoms directly adjacent to it in the crystal structure or the number of all hetero-ions combined with it.", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "coordination number", "B": "atomic packing factor", "C": "lattice parameter", "D": "ionic radius ratio" }, "correct_answer": "A", "explanation": "The correct answer is 'coordination number' because it specifically refers to the number of adjacent atoms or hetero-ions surrounding a central atom/ion in a crystal structure. Option 'B' (atomic packing factor) is a distractor that exploits volume-related intuition but actually describes the fraction of space occupied by atoms. Option 'C' (lattice parameter) triggers dimensional thinking but refers to unit cell dimensions. Option 'D' (ionic radius ratio) is a multi-level trap that seems plausible for coordination but actually determines stable coordination geometries based on size ratios.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 276, "question": "The reaction of forming mullite from Al2O3 and SiO powders is controlled by diffusion and conforms to the Jander equation. The experiment was conducted under constant temperature conditions. When the reaction proceeded for 1 hour, it was measured that 15% of the reactants had reacted. In how much time will all the reactants be converted into products?", "answer": "According to the Jander equation, [1-(1-0.15)^(1/3)]^2=k×1 ⇒ k=0.00278. The time required for the reaction to complete (G=1) is t=1/k=1/(2.78×10^(-3))=359.63h.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，解答过程涉及使用Jander方程进行数学推导和计算，最终得出具体的时间数值。 | 知识层次: 题目需要应用Jander方程进行多步计算，涉及反应进度与时间的关系推导，需要理解扩散控制的反应动力学模型，并进行数值计算和公式转换，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解Jander方程的应用并进行多步计算。题目要求考生首先根据已知条件计算反应速率常数k，然后利用该常数计算完全反应所需时间。这涉及到对扩散控制反应动力学的理解以及代数运算能力，属于综合性计算问题。", "convertible": true, "correct_option": "359.63h", "choice_question": "The reaction of forming mullite from Al2O3 and SiO powders is controlled by diffusion and conforms to the Jander equation. The experiment was conducted under constant temperature conditions. When the reaction proceeded for 1 hour, it was measured that 15% of the reactants had reacted. In how much time will all the reactants be converted into products?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "359.63h", "B": "44.44h", "C": "6.67h", "D": "100h" }, "correct_answer": "A", "explanation": "The correct answer is A (359.63h) because the Jander equation for diffusion-controlled reactions follows the relationship (1-(1-α)^(1/3))^2 = kt, where α is the fraction reacted. Solving for complete conversion (α=1) requires extrapolating from the 15% conversion at 1 hour. Option B (44.44h) is a linear extrapolation trap, dividing 100% by the 15% reaction rate. Option C (6.67h) is an inverse proportion error, calculating 1/0.15. Option D (100h) is a common intuitive but incorrect guess based on reaction completion time scales.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2615, "question": "Given that the atomic number of an element is 32, based on the knowledge of atomic electronic structure, write its electron configuration.", "answer": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p2", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求基于原子电子结构知识写出电子排布式，需要文字解释和论述，答案是一个具体的电子排布式而非数值计算或选择判断 | 知识层次: 题目考查对原子电子结构基础知识的记忆和理解，需要根据原子数直接写出电子排布式，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求根据给定的原子数直接写出电子排布，属于基础概念记忆的范畴。解题步骤简单，只需按照电子填充顺序（1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p）进行填写，无需复杂的分析或比较。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p2", "choice_question": "Given that the atomic number of an element is 32, which of the following is its correct electron configuration based on the knowledge of atomic electronic structure?", "conversion_reason": "The answer is a standard electron configuration, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p2", "B": "1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p2", "C": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p1 4d1", "D": "1s2 2s2 2p6 3s2 3p6 3d10 4s1 4p3" }, "correct_answer": "A", "explanation": "The correct answer is A because it follows the Aufbau principle and the order of orbital filling for atomic number 32 (Germanium). Option B incorrectly places 4s2 before 3d10, which is a common mistake due to the close energy levels. Option C introduces an incorrect 4d1 electron, exploiting the tendency to overcomplicate configurations. Option D violates Hund's rule by not maximizing parallel spins in the 4p orbitals, a subtle trap for those not considering electron repulsion effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4421, "question": "What is the purpose of a spheroidizing heat treatment?", "answer": "The purpose of a spheroidizing heat treatment is to produce a very soft and ductile steel alloy having a spheroiditic microstructure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释spheroidizing heat treatment的目的，答案是一个简短的文字解释，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查对热处理工艺目的的基本概念记忆和理解，属于基础知识的直接问答，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对spheroidizing heat treatment基本定义和目的的简单记忆，属于最基础的概念性知识。正确选项直接给出了明确的定义和目的，不需要任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The purpose of a spheroidizing heat treatment is to produce a very soft and ductile steel alloy having a spheroiditic microstructure.", "choice_question": "What is the purpose of a spheroidizing heat treatment?", "conversion_reason": "The answer is a standard definition or concept, which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To produce a very soft and ductile steel alloy having a spheroiditic microstructure", "B": "To increase the hardness of steel by forming dispersed carbide particles", "C": "To refine grain size through cyclic heating and cooling", "D": "To relieve internal stresses while maintaining the original microstructure" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the primary purpose of spheroidizing treatment - to create soft, ductile steel with spherical carbides. Option B is a cognitive bias trap, confusing spheroidizing with precipitation hardening. Option C exploits process confusion by describing thermo-mechanical treatment. Option D is a professional intuition trap, mixing up with stress relieving annealing while ignoring microstructural changes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 273, "question": "The formation reaction of mullite from Al2O3 and SiO powders is diffusion-controlled and conforms to the Jander equation. What effective measures should be taken to accelerate the formation of mullite?", "answer": "All factors favorable for diffusion can be employed to accelerate the formation of mullite: reducing particle size, using reactive reactants (such as Al2O3·3H2O), applying appropriate pressure, etc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求提出有效的措施来加速莫来石的形成，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求考生理解扩散控制反应的基本原理（Jander方程），并能综合运用扩散影响因素（如颗粒尺寸、反应物活性、压力等）来提出加速莫来石形成的具体措施。这需要多步概念关联和综合分析能力，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解扩散控制反应的基本原理，并能够综合分析多种促进扩散的因素（如粒径减小、反应物活性、压力等）对反应速率的影响。虽然不需要进行复杂的计算，但需要对Jander方程和相关概念有一定的掌握，并能将这些概念关联起来进行判断。", "convertible": true, "correct_option": "All factors favorable for diffusion can be employed to accelerate the formation of mullite: reducing particle size, using reactive reactants (such as Al2O3·3H2O), applying appropriate pressure, etc.", "choice_question": "Which of the following measures can be taken to accelerate the formation of mullite in a diffusion-controlled reaction conforming to the Jander equation?", "conversion_reason": "The answer is a standard list of measures that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Reducing particle size of reactants to increase surface area for diffusion", "B": "Adding excess SiO2 to shift the reaction equilibrium according to Le Chatelier's principle", "C": "Increasing the temperature gradient across the sample to enhance mass transport", "D": "Introducing a small amount of MgO to form a liquid phase at lower temperatures" }, "correct_answer": "A", "explanation": "The correct answer is A because the Jander equation explicitly shows that reaction rate in diffusion-controlled processes is inversely proportional to particle size. Option B is incorrect because Le Chatelier's principle applies to equilibrium systems, not diffusion-limited solid-state reactions. Option C is a trap for those confusing heat transfer with mass transport mechanisms. Option D exploits the common but incorrect intuition that liquid phase sintering always accelerates reactions, while in mullite formation it may actually hinder the desired reaction pathway.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2585, "question": "For a simple cubic crystal, pure bending of the (110) plane around the [001] axis will form what type of dislocations (specify the direction of the dislocation line and the Burgers vector).", "answer": "Edge type, dislocation line direction=[001], Burgers vector=a[100] or a[010]", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求详细解释和论述晶体弯曲形成的位错类型、位错线方向和伯格斯矢量，答案需要文字描述而非简单选择或判断。 | 知识层次: 题目需要理解晶体结构、位错类型和伯格斯矢量的概念，并能够将这些概念关联起来进行分析。虽然不涉及复杂的计算，但需要多步推理和概念关联，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合理解晶体结构、位错类型、伯格斯矢量等概念，并进行多步分析和关联。题目要求确定位错类型、位错线方向和伯格斯矢量，涉及多个知识点的综合应用和计算，超出了简单记忆或单一概念的应用。", "convertible": true, "correct_option": "Edge type, dislocation line direction=[001], Burgers vector=a[100] or a[010]", "choice_question": "For a simple cubic crystal, pure bending of the (110) plane around the [001] axis will form what type of dislocations (specify the direction of the dislocation line and the Burgers vector)?", "conversion_reason": "The answer is a standard terminology and concept in materials science, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Edge type, dislocation line direction=[001], Burgers vector=a[100] or a[010]", "B": "Screw type, dislocation line direction=[110], Burgers vector=a[001]", "C": "Mixed type, dislocation line direction=[111], Burgers vector=a/2[110]", "D": "Edge type, dislocation line direction=[110], Burgers vector=a/2[110]" }, "correct_answer": "A", "explanation": "The correct answer is A because pure bending of the (110) plane around [001] creates edge dislocations with line direction parallel to the bending axis [001]. The Burgers vector must lie in the slip plane (110), which are the a[100] or a[010] vectors. Option B is incorrect because it suggests a screw dislocation with incorrect line direction and Burgers vector. Option C is a mixed dislocation that doesn't match the pure bending condition. Option D uses the correct dislocation type but incorrect line direction and fractional Burgers vector that doesn't exist in simple cubic crystals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1049, "question": "Analyze the equilibrium crystallization process of the Fe-0.4%C alloy and indicate the microstructure constituents at room temperature", "answer": "When C%=0.4%, the microstructure constituents of the Fe-C alloy upon cooling to room temperature are P+α", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求分析Fe-0.4%C合金的平衡结晶过程并指出室温下的微观结构组成，需要文字解释和论述，答案也是以文字形式给出微观结构组成。 | 知识层次: 题目要求分析Fe-0.4%C合金的平衡结晶过程并指出室温下的微观组织成分，这需要理解相图、结晶过程以及组织转变的基本原理，并进行一定的综合分析。虽然涉及的知识点较为基础，但需要将多个概念关联起来，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解铁碳合金相图的基本概念，掌握平衡冷却过程中相变规律，并能正确关联0.4%C成分对应的最终室温组织（P+α）。虽然不涉及多步计算，但需要综合分析相图信息并做出正确判断。", "convertible": true, "correct_option": "P+α", "choice_question": "Analyze the equilibrium crystallization process of the Fe-0.4%C alloy and indicate the microstructure constituents at room temperature. The correct microstructure constituents are:", "conversion_reason": "The answer is a standard term (P+α) which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "P+α", "B": "P+Fe3C", "C": "α+Fe3C", "D": "P+α+Fe3C" }, "correct_answer": "A", "explanation": "The correct microstructure for Fe-0.4%C alloy at room temperature is pearlite (P) and ferrite (α). Option B incorrectly includes cementite (Fe3C) as a separate phase - a common misconception when pearlite is already present. Option C represents a hypereutectoid composition, exploiting confusion about the eutectoid point. Option D is an overcomplicated trap combining all possible phases, targeting AI's tendency to include all plausible components without considering phase equilibrium constraints.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 937, "question": "What is primary banded structure?", "answer": "Primary banded structure is formed by dendrites during solidification and becomes banded after hot rolling; under CuCl2 etching, the dark bands are dendrite trunks (with less solute), while the light bands are often interdendritic regions enriched with impurities, also known as original bands.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"primary banded structure\"进行文字解释和论述，答案提供了详细的定义和特征描述，符合简答题的特点。 | 知识层次: 题目考查对primary banded structure的定义和形成过程的基本记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项不仅需要考生记住\"primary banded structure\"的定义，还需要理解其形成过程（凝固过程中枝晶形成，经热轧后呈带状）和微观特征（在CuCl2腐蚀下不同区域的显色差异）。这超出了简单的定义记忆，需要对概念进行一定程度的解释和描述。但题目不涉及多个概念的比较或复杂体系的分析，因此不属于最高难度等级。", "convertible": true, "correct_option": "Primary banded structure is formed by dendrites during solidification and becomes banded after hot rolling; under CuCl2 etching, the dark bands are dendrite trunks (with less solute), while the light bands are often interdendritic regions enriched with impurities, also known as original bands.", "choice_question": "Which of the following best describes primary banded structure?", "conversion_reason": "The answer is a standard definition or description of a concept, which can be converted into a multiple-choice question format by presenting it as the correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Primary banded structure is formed by dendrites during solidification and becomes banded after hot rolling; under CuCl2 etching, the dark bands are dendrite trunks (with less solute), while the light bands are often interdendritic regions enriched with impurities, also known as original bands.", "B": "Primary banded structure results from alternating layers of ferrite and pearlite formed during slow cooling, where dark bands represent pearlite and light bands represent ferrite under standard metallographic etching.", "C": "Primary banded structure is caused by preferential diffusion of carbon atoms along specific crystallographic planes during annealing, creating periodic variations in microhardness that appear as bands under etching.", "D": "Primary banded structure arises from spinodal decomposition in certain alloy systems, producing nanoscale compositional fluctuations that manifest as alternating bands under high-resolution TEM observation." }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the dendritic origin and etching response of primary banded structure. Option B incorrectly describes secondary banding (ferrite-pearlite). Option C introduces an erroneous diffusion-based mechanism. Option D misleadingly applies spinodal decomposition theory which is irrelevant to primary banding formation. These distractors exploit common confusions between different types of banding structures and solid-state transformation mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2114, "question": "Point out the error in the following concept and correct it: The fundamental difference between ferrite and austenite lies in their different solid solubility, with the former being small and the latter large.", "answer": "The fundamental difference lies in their crystal structures, with the former being bcc and the latter fcc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出概念中的错误并进行纠正，需要文字解释和论述，而不是从选项中选择或进行数值计算。答案也以文字形式呈现，解释了晶体结构的差异。 | 知识层次: 题目考查对铁素体和奥氏体基本概念的记忆和理解，特别是它们的晶体结构差异，属于基础概念的记忆性知识。 | 难度: 在选择题中属于中等难度，需要理解并区分铁素体和奥氏体的基本概念，特别是它们的晶体结构差异。虽然题目涉及基础概念记忆，但需要考生能够识别错误并选择正确的定义，这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。", "convertible": true, "correct_option": "The fundamental difference lies in their crystal structures, with the former being bcc and the latter fcc.", "choice_question": "What is the fundamental difference between ferrite and austenite?", "conversion_reason": "The original short answer question asks for a correction to a specific concept, which can be rephrased as a multiple-choice question by presenting the correct statement as one of the options. The answer is a standard concept that can be clearly identified as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The fundamental difference lies in their crystal structures, with ferrite being bcc and austenite fcc", "B": "The key distinction is their carbon solubility limits, with ferrite dissolving <0.02 wt% C and austenite up to 2.14 wt% C", "C": "The primary difference is their magnetic properties, with ferrite being ferromagnetic and austenite paramagnetic", "D": "The essential variation is their thermal conductivity, with ferrite having higher values than austenite" }, "correct_answer": "A", "explanation": "The correct answer is A because the fundamental classification of these phases is based on crystal structure. Option B is a strong distractor as it describes a real but secondary characteristic. Option C exploits magnetic property differences that are true but not fundamental. Option D uses a real physical property difference but one that's a consequence rather than a defining feature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 964, "question": "Briefly describe segregation", "answer": "The non-uniformity of chemical composition in alloys.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述一个概念（segregation），答案以文字解释的形式给出，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查基本概念的记忆和理解，仅要求对\"segregation\"这一术语进行简单定义，不涉及复杂分析或应用。 | 难度: 在选择题型中，此题仅要求识别和回忆\"segregation\"的基本定义，属于最基础的概念记忆。正确选项直接给出了该术语的标准定义，不需要任何解释或推理过程，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The non-uniformity of chemical composition in alloys.", "choice_question": "Which of the following best describes segregation?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The non-uniformity of chemical composition in alloys", "B": "The separation of dislocations during plastic deformation", "C": "The preferential migration of vacancies to grain boundaries", "D": "The spontaneous phase separation in polymer blends" }, "correct_answer": "A", "explanation": "The correct answer is A because segregation specifically refers to the non-uniform distribution of alloying elements in solid solutions. Option B exploits confusion with dislocation dynamics, which is a deformation mechanism. Option C targets those who mistake vacancy diffusion for compositional variation. Option D is a polymer-specific phenomenon that doesn't apply to metallic alloys where segregation is most commonly discussed.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3894, "question": "An element that has the electron configuration 1 s^{2} 2 s^{2} 2 p^{6} has how many electrons? Enter numeric values only.", "answer": "9", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据给定的电子构型计算电子总数，需要数值计算，且答案仅要求输入数值。 | 知识层次: 题目考查电子排布的基本概念和简单计算，只需根据给定的电子排布式直接计算电子总数，属于基本公式应用和简单计算范畴。 | 难度: 在选择题型中，该题目仅需要直接计算电子配置中的电子总数，属于单一公式直接计算的简单应用。学生只需将1s²、2s²和2p⁶的电子数相加即可得到答案，无需复杂的推理或多步骤计算。", "convertible": true, "correct_option": "9", "choice_question": "An element that has the electron configuration 1 s^{2} 2 s^{2} 2 p^{6} has how many electrons?", "conversion_reason": "The question is a calculation problem with a definite numeric answer, which can be converted into a multiple-choice format by providing options including the correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项B", "B": "9", "C": "选项D", "D": "选项C" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 265, "question": "Analyze the reasons why the diffusion coefficient of anions is generally smaller than that of cations in ionic crystals.", "answer": "In ionic crystals, anions generally form close packing, while cations fill the tetrahedral or octahedral voids. Therefore, cations diffuse more easily. If anions diffuse, the crystal packing arrangement must be altered, disrupting the structural framework of the ionic crystal, which results in greater resistance. Hence, in ionic crystals, the diffusion coefficient of anions is generally smaller than that of cations.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析离子晶体中阴离子扩散系数通常小于阳离子的原因，答案通过文字解释和论述来回答，没有涉及选择、判断或计算。 | 知识层次: 题目要求分析离子晶体中阴离子扩散系数小于阳离子的原因，涉及对晶体结构、扩散机制和能量障碍的综合理解。需要解释阴离子紧密堆积和阳离子占据空隙的结构特点，以及扩散过程中结构框架改变带来的阻力增加。这种分析需要将多个概念关联起来，并进行推理和机理解释，属于较高层次的认知能力。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解离子晶体中阴离子和阳离子的扩散机制，还需要深入分析晶体结构对扩散系数的影响。正确选项涉及对晶体堆积方式、空隙填充以及结构框架破坏的综合考量，需要考生具备复杂的推理分析能力和机理解释能力。这种题目在选择题中属于对知识深度和综合运用能力要求极高的类型。", "convertible": true, "correct_option": "In ionic crystals, anions generally form close packing, while cations fill the tetrahedral or octahedral voids. Therefore, cations diffuse more easily. If anions diffuse, the crystal packing arrangement must be altered, disrupting the structural framework of the ionic crystal, which results in greater resistance. Hence, in ionic crystals, the diffusion coefficient of anions is generally smaller than that of cations.", "choice_question": "Why is the diffusion coefficient of anions generally smaller than that of cations in ionic crystals?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice structure by asking for the reason behind the phenomenon.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Anions form close packing while cations occupy interstitial sites, requiring greater structural rearrangement for anion diffusion", "B": "Anions have larger ionic radii which increases their activation energy for diffusion", "C": "Cations experience stronger electrostatic repulsion from surrounding ions, enhancing their mobility", "D": "The higher polarizability of anions creates stronger local bonding that hinders diffusion" }, "correct_answer": "A", "explanation": "The correct answer A addresses the fundamental structural arrangement in ionic crystals where anions form the framework. Distractors employ multiple strategies: B uses a plausible size argument but ignores the structural context, C reverses the expected electrostatic effects, and D introduces a valid but secondary factor (polarizability) that could mislead models to overemphasize bonding effects over structural constraints.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3904, "question": "For a metal that has the simple cubic crystal structure, calculate the atomic radius if the metal has a density of 2.05g / {cm}^{3} and an atomic weight of 77.84g / mol.", "answer": "the atomic radius is 0.122nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解金属的原子半径，答案是一个具体的数值结果（0.122nm），符合计算题的特征。 | 知识层次: 题目需要多步计算和概念关联，包括晶体结构、密度、原子量和原子半径的综合计算，涉及公式应用和单位转换，思维过程有一定深度要求。 | 难度: 在选择题中属于中等偏上难度，需要综合运用晶体结构、密度计算和单位换算等多个概念。解题涉及多步计算（包括晶格常数推导、原子体积计算和半径换算），但选择题型通过选项提供了明确的目标方向，降低了开放题型的复杂度。需要理解简单立方晶体的几何关系（a=2r）并能将宏观密度与微观结构参数相关联，但不需要处理多变量或复杂公式推导。", "convertible": true, "correct_option": "0.122nm", "choice_question": "For a metal that has the simple cubic crystal structure, the atomic radius is: (Given: density = 2.05g/cm³, atomic weight = 77.84g/mol)", "conversion_reason": "The calculation problem has a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.122 nm", "B": "0.144 nm", "C": "0.156 nm", "D": "0.134 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.122 nm) calculated using the formula for simple cubic structure: r = (3V/4π)^(1/3), where V is the atomic volume derived from density and atomic weight. Option B (0.144 nm) is a common mistake from incorrectly assuming FCC packing. Option C (0.156 nm) results from forgetting to convert units from cm to nm. Option D (0.134 nm) appears plausible as it's close to typical metallic radii, but doesn't match the given parameters.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 704, "question": "First-order phase transition", "answer": "During the phase transition, the chemical potentials of the two phases are equal, but the first-order partial derivatives of the chemical potential are not equal. A first-order phase transition involves latent heat and changes in volume.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"First-order phase transition\"进行文字解释和论述，答案提供了详细的定义和特征描述，符合简答题的特点 | 知识层次: 题目考查对一级相变基本概念的记忆和理解，包括化学势相等但一阶导数不等、潜热和体积变化等特征，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并区分化学势的一阶偏导数在相变中的不同表现，以及一级相变的特征（如潜热和体积变化）。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "During the phase transition, the chemical potentials of the two phases are equal, but the first-order partial derivatives of the chemical potential are not equal. A first-order phase transition involves latent heat and changes in volume.", "choice_question": "Which of the following statements correctly describes a first-order phase transition?", "conversion_reason": "The original short answer question asks for a description of a first-order phase transition, which can be converted into a multiple-choice question by providing the correct description as one of the options and asking the examinee to select the correct one.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "During the phase transition, the chemical potentials of the two phases are equal, but the first-order partial derivatives of the chemical potential are not equal. A first-order phase transition involves latent heat and changes in volume.", "B": "The free energy curves of the two phases intersect at the transition temperature, with continuous first derivatives but discontinuous second derivatives of free energy.", "C": "The phase transition occurs when the Gibbs free energies of the two phases become equal, accompanied by a discontinuity in the first derivative of entropy with respect to temperature.", "D": "Both phases maintain identical chemical potential and its first derivatives during the transition, with the distinction appearing only in higher-order thermodynamic quantities." }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the thermodynamic characteristics of first-order phase transitions, where chemical potentials equalize but their first derivatives differ, accompanied by latent heat and volume changes. Option B incorrectly describes a second-order transition with continuous first derivatives. Option C mixes correct elements with incorrect discontinuity in entropy derivative. Option D is a subtle trap suggesting continuous first derivatives, which contradicts the fundamental definition of first-order transitions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2087, "question": "Point out the errors in the following concept and correct them: (19) When a pure metal crystallizes and grows vertically, its interface is sometimes smooth and sometimes rough, growing alternately.", "answer": "The interface is of the rough type.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出概念中的错误并进行纠正，需要文字解释和论述，而不是简单的选择或判断 | 知识层次: 题目考查对金属结晶界面类型的基础概念记忆和理解，仅需识别并纠正错误描述，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解金属结晶过程中界面类型的分类（光滑界面与粗糙界面），并能准确识别题目中描述的错误概念。正确选项直接给出了界面的正确类型，但考生需要基于对结晶过程的基本原理的理解来判断。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。", "convertible": true, "correct_option": "The interface is of the rough type.", "choice_question": "When a pure metal crystallizes and grows vertically, its interface is sometimes smooth and sometimes rough, growing alternately. Which of the following correctly describes the interface type?", "conversion_reason": "The answer is a standard concept or term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The interface is of the rough type due to continuous atomic attachment at multiple sites", "B": "The interface alternates between smooth and rough due to periodic changes in undercooling", "C": "The interface remains smooth as it grows vertically with minimal surface energy", "D": "The interface exhibits faceted growth with alternating smooth and rough regions" }, "correct_answer": "A", "explanation": "The correct answer is A because during vertical growth of pure metals, the interface is typically rough due to continuous atomic attachment at multiple sites, allowing for fast growth. Option B exploits the common misconception that interface morphology changes with undercooling, while in reality it's determined by the Jackson factor. Option C appeals to the intuitive but incorrect assumption that vertical growth implies smooth interfaces. Option D introduces a faceted growth red herring, which doesn't apply to pure metal crystallization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3876, "question": "Describe the hardness and microstructure in an eutectoid steel that has been heated to 300^{\\circ} C, quenched to 300^{\\circ} C and held for 10s, and finally quenched to room temperature.", "answer": "HRC=66 and the microstructure is all martensite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求描述材料的硬度和微观结构，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求理解并应用钢的热处理过程对硬度和微观结构的影响，涉及多步热处理工艺（加热、淬火、保温）与最终组织（马氏体）和性能（硬度）的关联分析。虽然答案直接给出了结果，但完整回答需要解释为什么在特定条件下会形成全马氏体组织及其对应的硬度值，这超出了简单记忆或直接套用基础概念的范畴，属于需要综合分析热处理工艺-组织-性能关系的应用层次。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目涉及多步热处理过程（加热、淬火、保温、再淬火），要求考生理解每个步骤对材料组织和性能的影响。其次，需要综合应用相变动力学和TTT图的知识，分析在300°C保温10秒是否足以形成贝氏体或保留奥氏体。最后，题目要求将微观组织（全马氏体）与宏观性能（HRC=66）精确对应，这需要深入理解马氏体转变的硬度和组织特征。虽然题目提供了正确选项，但解题过程涉及多角度分析和概念关联，超出了简单记忆或单一概念应用的范畴。", "convertible": true, "correct_option": "HRC=66 and the microstructure is all martensite.", "choice_question": "What are the hardness and microstructure in an eutectoid steel that has been heated to 300°C, quenched to 300°C and held for 10s, and finally quenched to room temperature?", "conversion_reason": "The answer is a standard and specific description, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "HRC=66 and the microstructure is all martensite", "B": "HRC=45 with a mixture of bainite and retained austenite", "C": "HRC=58 with tempered martensite and some pearlite", "D": "HRC=40 with predominantly upper bainite structure" }, "correct_answer": "A", "explanation": "The correct answer is A because heating to 300°C is below the A1 temperature, so no phase transformation occurs initially. The first quench to 300°C is irrelevant as it's still above Ms. The 10s hold at 300°C is too short for any transformation, and final quenching to room temperature produces full martensite with typical hardness. Option B exploits the common misconception that holding at intermediate temperatures always produces bainite. Option C tempts with plausible hardness values but incorrectly suggests partial transformation during the brief hold. Option D targets the intuition that any isothermal hold must result in bainite formation, ignoring the critical time factor.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2624, "question": "Given that the atomic number of an element is 32, determine the strength of its metallic character based on its electron configuration.", "answer": "Metalloid Ge", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求根据给定的原子序数确定元素的金属特性，并基于电子构型进行解释。答案需要文字描述（\"Metalloid Ge\"）而非选择、判断或计算。 | 知识层次: 题目需要根据原子序数确定元素（锗），并分析其电子构型以判断金属性强度。这涉及多步推理和概念关联，包括元素周期表位置、电子构型与金属性之间的关系等综合分析。虽然不涉及复杂计算，但需要一定的概念理解和应用能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求根据原子序数32确定元素的金属性强度，涉及电子排布和元素周期表位置的综合分析。虽然解题步骤较为直接（确定元素为Ge并识别其类金属性质），但需要学生掌握电子构型与周期性趋势的关联知识，属于中等应用层次的多步计算和概念关联题型。", "convertible": true, "correct_option": "Metalloid Ge", "choice_question": "Given that the atomic number of an element is 32, which of the following best describes the strength of its metallic character based on its electron configuration?", "conversion_reason": "The answer is a standard term (Metalloid Ge) which can be used as a correct option in a multiple-choice question. The original question can be rephrased to fit a multiple-choice format by asking for the best description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Strong metallic character due to complete d-orbital filling", "B": "Weak metallic character with predominant covalent bonding", "C": "Transition metal with variable metallic character", "D": "Pure non-metal with no metallic properties" }, "correct_answer": "B", "explanation": "The element with atomic number 32 is germanium (Ge), a metalloid. The correct answer is B because Ge exhibits weak metallic character with predominant covalent bonding due to its position in the periodic table and electron configuration [Ar]3d10 4s2 4p2. Option A exploits the cognitive bias of associating d-orbital filling with strong metallicity (true for transition metals but not here). Option C creates a transition metal misconception (Ge isn't a transition metal). Option D exaggerates the non-metallic character, ignoring its actual metalloid properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1435, "question": "Ferrite is a solid solution of carbon in what type of iron?", "answer": "α", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的术语（α铁），不需要从多个选项中选择，也不需要计算或判断对错，属于简答题类型。 | 知识层次: 题目考查对铁素体（Ferrite）基本定义的记忆，即碳在α铁中的固溶体。这属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 该题目属于基础概念记忆类型，仅需识别铁素体是碳在α铁中的固溶体这一基本定义。选择题型中只需选择正确选项\"α\"，无需复杂推理或多概念比较，属于最基础的定义简答难度。", "convertible": true, "correct_option": "α", "choice_question": "Ferrite is a solid solution of carbon in which type of iron?", "conversion_reason": "The answer is a standard term (α-iron), which can be presented as a correct option among other plausible options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "α-iron (BCC structure at room temperature)", "B": "γ-iron (FCC structure at high temperature)", "C": "δ-iron (BCC structure at very high temperature)", "D": "ε-iron (HCP structure under high pressure)" }, "correct_answer": "A", "explanation": "Ferrite is correctly defined as a solid solution of carbon in α-iron (BCC structure). The high-difficulty interference items exploit: 1) B选项利用高温相γ-iron的常见认知偏差；2) C选项利用同为BCC结构的δ-iron制造结构混淆；3) D选项引入高压相ε-iron制造极端条件干扰。所有干扰项都是真实存在的铁同素异形体，但在定义铁素体时都错误。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 781, "question": "1. Network former", "answer": "Network former: substances with single bond energy ≥335kJ/mol that can form glass independently.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Network former\"进行定义和解释，答案以文字形式给出详细说明，符合简答题的特征 | 知识层次: 题目考查对\"Network former\"这一基础概念的定义和分类的记忆和理解，属于材料科学中玻璃形成物质的基本原理知识。 | 难度: 在选择题型中，该题目仅考察对\"Network former\"这一基础概念的定义记忆，属于最基础的知识点掌握要求。题目直接给出了明确定义，无需解释或比较分析，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "substances with single bond energy ≥335kJ/mol that can form glass independently", "choice_question": "Which of the following best describes a Network former?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "substances with single bond energy ≥335kJ/mol that can form glass independently", "B": "materials with coordination number ≤4 that can modify glass structure", "C": "elements with electronegativity >1.7 that require modifiers to form glass", "D": "compounds with bond angles <120° that stabilize glass networks" }, "correct_answer": "A", "explanation": "The correct answer is A because network formers are defined by their ability to independently form glass networks due to strong covalent bonds (≥335kJ/mol). Option B is a cognitive bias trap, confusing network formers with modifiers which typically have CN≤4. Option C exploits professional intuition by using electronegativity (a related but insufficient parameter) and falsely suggesting modifier dependence. Option D is a multi-level verification trap using accurate bond angle data but applying it incorrectly to network formation criteria.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4434, "question": "Calculate the fraction of lattice sites that are Schottky defects for sodium chloride at its melting temperature \\left(801^{\\circ} C\\right). Assume an energy for defect formation of 2.3 \\mathrm{eV}.", "answer": "the fraction of lattice sites that are schottky defects for sodium chloride at its melting temperature is 4.03 × 10^{-6}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算Schottky缺陷的分数），并给出了具体的能量值和温度条件，答案也是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括温度转换、能量单位转换以及应用Schottky缺陷浓度公式。虽然计算过程较为直接，但需要理解缺陷形成能的概念以及公式中各参数的含义，并正确代入数值进行计算。这属于中等应用层次，需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解Schottky缺陷的概念，掌握缺陷形成能的计算方法，并能正确应用Arrhenius公式进行多步骤计算。题目涉及温度单位转换、能量单位统一以及指数运算等综合计算过程，但选项已经给出了计算结果，减少了部分计算复杂度。", "convertible": true, "correct_option": "4.03 × 10^{-6}", "choice_question": "What is the fraction of lattice sites that are Schottky defects for sodium chloride at its melting temperature (801°C), assuming an energy for defect formation of 2.3 eV?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.03 × 10^{-6}", "B": "1.23 × 10^{-5}", "C": "2.15 × 10^{-7}", "D": "6.78 × 10^{-4}" }, "correct_answer": "A", "explanation": "正确答案A是通过玻尔兹曼分布公式计算得到的精确值，考虑了温度(1074K)和缺陷形成能(2.3eV)。干扰项B利用了常见错误，即忽略温度单位转换(直接使用801而非开尔文温度)。干扰项C利用了指数计算中常见的符号错误(负号遗漏)。干扰项D利用了直觉陷阱，即高熔点材料缺陷浓度可能较高的错误联想。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 36, "question": "Calculate the ratio of octahedral void number to O2- number", "answer": "The ratio of octahedral void number to O2- number is 1:1", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算八面体空隙数与O2-离子数的比例），答案是一个具体的数值比例（1:1），这符合计算题的特征。 | 知识层次: 题目涉及基本的晶体结构概念（八面体空隙和氧离子数量）和简单的比例计算，属于直接套用基本公式和概念的应用层面，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用基本公式进行计算，属于单一公式直接计算的难度等级。题目明确给出了正确选项，且解题步骤简单，无需复杂的推理或多步骤计算。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "1:1", "choice_question": "What is the ratio of octahedral void number to O2- number?", "conversion_reason": "The answer is a specific ratio, which can be presented as a choice among other plausible ratios.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1:1", "B": "2:1", "C": "1:2", "D": "4:1" }, "correct_answer": "A", "explanation": "The correct answer is A (1:1) because in a close-packed structure, the number of octahedral voids is equal to the number of anions (O2-). Option B (2:1) is a cognitive bias trap, exploiting the common misconception that octahedral voids are twice as numerous as tetrahedral voids. Option C (1:2) is a professional intuition trap, reversing the correct ratio to mislead those recalling the cation:anion ratio in some compounds. Option D (4:1) is a multi-level verification trap, using a plausible-looking but irrelevant ratio from different crystal structures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1429, "question": "The type of bonding in a material determines the level of its elastic modulus. What type of bond predominates in metallic materials, how strong is the bonding, and consequently, what is their elastic modulus like?", "answer": "Metallic materials are primarily bonded by metallic bonds, which are relatively weak, resulting in a lower elastic modulus.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要解释金属材料中的主要键合类型、键合强度及其对弹性模量的影响，答案以文字解释和论述的形式呈现，符合简答题的特征。 | 知识层次: 题目考查金属材料中主要键合类型及其对弹性模量的影响，属于基础概念的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接询问金属材料的主要键合类型、键合强度及其对弹性模量的影响，正确选项仅需记忆金属键的基本特性（相对较弱，导致较低的弹性模量），无需额外推理或跨概念整合。知识点明确且单一，符合等级1对「基础概念记忆」的要求。", "convertible": true, "correct_option": "Metallic materials are primarily bonded by metallic bonds, which are relatively weak, resulting in a lower elastic modulus.", "choice_question": "What type of bond predominates in metallic materials, how strong is the bonding, and consequently, what is their elastic modulus like?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metallic bonds, moderately strong, resulting in intermediate elastic modulus comparable to covalent solids", "B": "Metallic bonds, relatively weak, leading to lower elastic modulus than ionic crystals", "C": "Mixed covalent-metallic bonds, very strong, producing exceptionally high elastic modulus", "D": "Secondary bonds dominating, extremely weak, causing elastic modulus similar to polymers" }, "correct_answer": "B", "explanation": "The correct answer is B because metallic bonds are indeed relatively weak compared to ionic or covalent bonds, resulting in lower elastic modulus. Option A is incorrect by overestimating metallic bond strength and modulus. Option C falsely introduces covalent character. Option D completely misrepresents the primary bonding type in metals. Advanced AIs may select A due to overgeneralization from high-modulus exceptions like tungsten, or C due to confusion with intermetallic compounds.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3468, "question": "For a machine tool spindle made of 40Cr steel, the core requires good strength and toughness (200-300HB), while the journal needs to be hard and wear-resistant (HRC54-58). What preparatory heat treatment should be selected?", "answer": "Preparatory heat treatment: Quenching + high-temperature tempering, tempered sorbite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述选择特定预备热处理的原因，答案提供了详细的文字解释而非选择或计算。 | 知识层次: 题目要求根据材料的不同部位性能需求选择合适的预备热处理工艺，涉及对材料热处理工艺的理解和应用，需要综合分析材料的性能要求和热处理工艺的效果，属于中等应用层次。 | 难度: 在选择题型内，这道题目属于较高难度，原因如下：", "convertible": true, "correct_option": "Quenching + high-temperature tempering, tempered sorbite", "choice_question": "For a machine tool spindle made of 40Cr steel, the core requires good strength and toughness (200-300HB), while the journal needs to be hard and wear-resistant (HRC54-58). What preparatory heat treatment should be selected?", "conversion_reason": "The answer is a standard term in heat treatment processes, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Quenching + high-temperature tempering (tempered sorbite)", "B": "Normalizing + surface induction hardening", "C": "Full annealing + carburizing", "D": "Austempering to obtain bainite structure" }, "correct_answer": "A", "explanation": "The correct answer is A because 40Cr steel requires quenching for core strength followed by high-temperature tempering to achieve tempered sorbite structure (200-300HB). The journal can then be surface hardened. B is wrong because normalizing alone cannot provide sufficient core strength. C is wrong because carburizing is unnecessary for 40Cr's core properties. D is wrong because austempering would not achieve the required core hardness range.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1007, "question": "From the perspective of bonding, analyze the characteristics of metallic materials", "answer": "Metallic materials: Primarily bonded by metallic bonds, most metals exhibit high strength and hardness, along with good plasticity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求从键合角度分析金属材料的特性，需要文字解释和论述，答案也是以文字形式给出分析结果 | 知识层次: 题目要求从键合的角度分析金属材料的特性，这需要综合运用金属键的基本原理，理解键合与材料性能之间的关系，并进行推理分析。这超出了简单记忆或基本应用的范围，属于对知识的深度理解和综合分析。 | 难度: 在选择题型内，该题目要求从键合角度分析金属材料的特性，涉及金属键的本质及其对材料性能的影响。这需要考生不仅掌握金属键的基本概念，还要能够综合运用这些知识解释材料的强度、硬度和塑性等复杂现象。题目要求的知识层次属于\"复杂分析\"，需要考生进行推理分析和机理解释，这在选择题型中属于最高难度等级。", "convertible": true, "correct_option": "Metallic materials: Primarily bonded by metallic bonds, most metals exhibit high strength and hardness, along with good plasticity.", "choice_question": "Which of the following best describes the bonding characteristics of metallic materials?", "conversion_reason": "The answer is a standard description of metallic materials' bonding characteristics, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metallic materials: Primarily bonded by metallic bonds, most metals exhibit high strength and hardness, along with good plasticity", "B": "Metallic materials: Dominated by ionic bonds with covalent character, leading to high electrical conductivity but low thermal stability", "C": "Metallic materials: Feature a unique hybrid of covalent and van der Waals bonds, explaining their exceptional optical properties", "D": "Metallic materials: Primarily held together by directional covalent bonds, resulting in anisotropic mechanical properties" }, "correct_answer": "A", "explanation": "The correct answer is A because metallic materials are fundamentally characterized by metallic bonding, which involves a 'sea' of delocalized electrons that explains their key properties. Option B incorrectly introduces ionic bonding, which is characteristic of ceramics. Option C falsely suggests covalent and van der Waals bonds, which are irrelevant to metallic bonding. Option D's claim about directional covalent bonds is a common misconception - metallic bonds are actually non-directional, which is why metals are isotropic in their bulk form.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2749, "question": "The $c/a$ ratio for an ideal hexagonal close-packed metal is ", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案，答案以选项字母形式给出 | 知识层次: 题目考查对理想六方密堆积金属的c/a比值的记忆，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念记忆类型，仅需直接回忆理想六方密堆积金属的$c/a$比值这一具体数值即可作答。在选择题型中，此类直接考察定义或基本数值的记忆性题目属于最简单的难度等级，无需理解或分析过程。", "convertible": true, "correct_option": "B", "choice_question": "The $c/a$ ratio for an ideal hexagonal close-packed metal is", "conversion_reason": "原题目已经是选择题（单选题）格式，可以直接转换。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.633", "B": "√(8/3)", "C": "2√2", "D": "π/√2" }, "correct_answer": "B", "explanation": "The correct answer is B (√(8/3)) because the ideal c/a ratio for HCP is derived from the geometric arrangement of spheres, where c/a = √(8/3) ≈ 1.633. Option A is the decimal approximation of the correct value, which may mislead models relying on memorized constants. Option C (2√2) is a common mistake from confusing HCP with simple cubic packing. Option D (π/√2) is a mathematically plausible but physically meaningless construction designed to exploit pattern recognition tendencies in AI models.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4359, "question": "In terms of heat treatment and the development of microstructure, what is one major limitation of the iron-iron carbide phase diagram related to time-temperature relationships?", "answer": "The diagram provides no indication as to the time-temperature relationships for the formation of pearlite, bainite, and spheroidite, all of which are composed of the equilibrium ferrite and cementite phases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释铁-碳相图在热处理和微观结构发展中的一个主要局限性，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求分析铁碳相图在热处理和显微组织发展中的局限性，涉及对相图的理解以及时间-温度关系的应用，需要将多个概念关联并进行综合分析。虽然不涉及复杂计算，但需要对相图的基本原理和实际应用有较深入的理解。 | 难度: 在选择题中属于中等难度，需要理解铁-碳相图的基本概念，并能够分析其局限性。题目要求考生将相图与实际热处理过程中的时间-温度关系联系起来，进行综合分析。虽然不需要多步计算，但需要对相图的应用和微观结构形成有较深入的理解。", "convertible": true, "correct_option": "The diagram provides no indication as to the time-temperature relationships for the formation of pearlite, bainite, and spheroidite, all of which are composed of the equilibrium ferrite and cementite phases.", "choice_question": "What is one major limitation of the iron-iron carbide phase diagram related to time-temperature relationships in terms of heat treatment and the development of microstructure?", "conversion_reason": "The answer is a standard concept and can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diagram fails to account for the effect of cooling rate on the formation of martensite", "B": "The diagram provides no indication as to the time-temperature relationships for the formation of pearlite, bainite, and spheroidite", "C": "The diagram cannot predict the exact hardness values resulting from different heat treatments", "D": "The diagram omits the influence of alloying elements on phase transformation kinetics" }, "correct_answer": "B", "explanation": "The correct answer is B because the iron-iron carbide phase diagram is an equilibrium diagram that shows only stable phases, not the kinetics of phase formation. Option A is a strong distractor because martensite formation is indeed rate-dependent, but this is not the primary limitation regarding time-temperature relationships. Option C exploits the common misconception that phase diagrams should predict mechanical properties. Option D uses the valid point about alloying effects but misapplies it to the core limitation of time-temperature relationships.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2247, "question": "During solid-state phase transformation, assuming the new phase nucleus is spherical and the volume free energy change per atom ΔGv=200ΔT/Tc (J/cm³), the critical transformation temperature Tc=1000K, the strain energy Es=4 J/cm³, the coherent interface energy γ_coherent=40×10⁻⁷ J/cm², and the incoherent interface energy γ_incoherent=400×10⁻⁷ J/cm², calculate ΔT when ΔG_coherent* = ΔG_incoherent*.", "answer": "Let ΔG_coherent* = ΔG_incoherent*, then (40×10⁻⁷)³ / (200×ΔT/1000 - 4)² = (400×10⁻⁷)³ / (200×ΔT/1000)². Solving gives ΔT ≈ 21K.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解ΔT的值，答案也是通过具体的计算步骤得出的数值结果。 | 知识层次: 题目涉及多步计算和概念关联，需要理解相变过程中的能量变化，并应用临界形核功的公式进行推导和计算。虽然不涉及复杂的机理分析或创新设计，但需要综合分析多个参数之间的关系，并进行适当的数学处理。 | 难度: 在选择题型内，该题目属于复杂多变量计算问题。题目要求考生理解固态相变中的多个关键概念（如体积自由能变化、应变能、共格与非共格界面能），并建立它们之间的数学关系。解题过程涉及多个步骤的代数运算和方程求解，包括设定方程、代入数值、解方程等。此外，题目还要求考生能够综合应用这些概念来比较共格和非共格形核的临界条件。这种综合性和复杂性在选择题型中属于较高难度，因此评估为等级4。", "convertible": true, "correct_option": "21K", "choice_question": "During solid-state phase transformation, assuming the new phase nucleus is spherical and the volume free energy change per atom ΔGv=200ΔT/Tc (J/cm³), the critical transformation temperature Tc=1000K, the strain energy Es=4 J/cm³, the coherent interface energy γ_coherent=40×10⁻⁷ J/cm², and the incoherent interface energy γ_incoherent=400×10⁻⁷ J/cm², calculate ΔT when ΔG_coherent* = ΔG_incoherent*. The correct ΔT is:", "conversion_reason": "The problem is a calculation question with a definite numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "21K", "B": "42K", "C": "10.5K", "D": "84K" }, "correct_answer": "A", "explanation": "The correct answer is A (21K) because it satisfies the condition ΔG_coherent* = ΔG_incoherent* when solving the Gibbs free energy equation for spherical nuclei formation. Option B (42K) is designed to exploit the common error of doubling the correct value due to misapplication of the interface energy ratio. Option C (10.5K) targets those who might incorrectly halve the correct value by confusing coherent/incoherent energy relationships. Option D (84K) is an extreme value trap that might catch those who misplace decimal points in interface energy calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1436, "question": "Metals with finer grains have _ (17) plasticity and toughness than the same metals with coarser grains", "answer": "(17) better", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个单词（better）来补全句子，属于简答题类型，需要根据材料科学知识进行简短回答 | 知识层次: 题目考查金属晶粒尺寸与塑性、韧性关系的基本概念记忆，属于材料科学中最基础的知识点，仅需记忆和理解即可作答。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即金属晶粒尺寸与塑性、韧性关系的简单事实。无需解释或分析，只需识别正确选项\"better\"即可。属于最基础的定义简答级别。", "convertible": true, "correct_option": "better", "choice_question": "Metals with finer grains have _ (17) plasticity and toughness than the same metals with coarser grains", "conversion_reason": "The short answer question can be converted into a multiple-choice question because the answer is a standard term ('better') that can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "better", "B": "lower", "C": "similar", "D": "temperature-dependent" }, "correct_answer": "A", "explanation": "正确答案是A，因为根据Hall-Petch关系，晶粒细化会同时提高材料的强度和塑性。干扰项B利用了对强度-塑性权衡关系的直觉误解；干扰项C利用了纳米晶材料中可能出现的反Hall-Petch效应这一特殊情况；干扰项D则通过引入真实但无关的温度变量制造迷惑。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 23, "question": "Based on the radius ratio relationship, determine the coordination number of K+ when coordinated with O2-. Given rO2-=0.132nm and rK+=0.131nm.", "answer": "For K+, r+/r-=0.131/0.132=0.99; according to the relationship between cation coordination number and the radius ratio of positive to negative ions, the coordination number is 8.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求基于半径比关系进行计算，以确定K+的配位数。解答过程中需要进行数值计算（r+/r- = 0.131/0.132 = 0.99）并应用半径比与配位数的关系规则。答案是一个具体的数值结果（配位数为8），符合计算题的特征。 | 知识层次: 题目涉及基本的半径比计算和直接套用协调数与半径比的关系表，属于基本公式应用和简单计算范畴，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用半径比公式进行计算，解题步骤简单且单一，属于最基础的难度等级。学生只需掌握半径比与配位数之间的基本关系，并进行简单的除法运算即可得出正确答案，无需复杂的分析或多步骤推理。", "convertible": true, "correct_option": "8", "choice_question": "Based on the radius ratio relationship, what is the coordination number of K+ when coordinated with O2-? Given rO2-=0.132nm and rK+=0.131nm.", "conversion_reason": "The answer is a specific numerical value (8), which can be presented as a choice among other plausible coordination numbers.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项D", "B": "8", "C": "选项B", "D": "选项C" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1125, "question": "Why can the lever rule be used to analyze the relative content of each phase in the horizontal section of a ternary equilibrium phase diagram", "answer": "On the horizontal section (i.e., the four-phase equilibrium plane) of a ternary equilibrium phase diagram, the composition of each phase and the temperature are all determined, so the lever rule can be used to analyze the relative content of each phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么杠杆定律可以用于分析三元平衡相图中水平截面上各相的相对含量，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解三元平衡相图中水平截面的特性，并应用杠杆规则来分析各相的相对含量。这涉及到多个概念的关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解杠杆规则在三元平衡相图中的具体应用，并能够将多个概念（如四相平衡平面、相组成确定等）进行关联分析。虽然题目提供了正确选项，但考生仍需具备一定的综合分析能力才能准确理解并选择正确答案。", "convertible": true, "correct_option": "On the horizontal section (i.e., the four-phase equilibrium plane) of a ternary equilibrium phase diagram, the composition of each phase and the temperature are all determined, so the lever rule can be used to analyze the relative content of each phase.", "choice_question": "Why can the lever rule be used to analyze the relative content of each phase in the horizontal section of a ternary equilibrium phase diagram?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The lever rule applies because the composition of each phase is fixed at a given temperature on the horizontal section", "B": "The lever rule can be used because the ternary system reduces to a binary system on the horizontal section", "C": "The lever rule is applicable due to the constant chemical potential gradient across phases", "D": "The lever rule works because the horizontal section represents an isothermal plane where Gibbs phase rule allows phase fraction calculation" }, "correct_answer": "A", "explanation": "The correct answer is A because on the horizontal section (isothermal plane) of a ternary phase diagram, the compositions of all coexisting phases are fixed, allowing the lever rule to determine phase fractions. Option B is incorrect because ternary systems do not reduce to binary on horizontal sections. Option C misapplies the concept of chemical potential gradients. Option D partially describes the condition but incorrectly attributes the lever rule's applicability to Gibbs phase rule rather than fixed phase compositions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2526, "question": "Explain the term: electron concentration", "answer": "The average number of valence electrons per atom in an alloy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释术语\"electron concentration\"，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，仅需解释电子浓度的定义，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆并选择电子浓度的基本定义，属于基础概念的直接回忆，无需复杂分析或推理步骤。", "convertible": true, "correct_option": "The average number of valence electrons per atom in an alloy.", "choice_question": "Which of the following best defines the term 'electron concentration'?", "conversion_reason": "The answer is a standard definition of a term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The average number of valence electrons per atom in an alloy", "B": "The total number of electrons in the conduction band of a semiconductor", "C": "The density of free electrons in a unit cell of a metal", "D": "The ratio of electron mobility to hole mobility in a doped material" }, "correct_answer": "A", "explanation": "The correct answer is A because electron concentration specifically refers to the average number of valence electrons contributed by each atom in an alloy, which is crucial for understanding alloy properties. Option B is a cognitive bias trap, confusing it with carrier concentration in semiconductors. Option C exploits professional intuition by using a seemingly related but incorrect definition for metals. Option D is a multi-level verification trap, mixing electron concentration with mobility ratios that are irrelevant to the actual definition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3513, "question": "Please indicate the type of cast iron and heat treatment method that should be used for the machine tool bed, and why?", "answer": "Machine tool bed: gray cast iron, (as-cast) HT250, stress relief annealing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述选择特定铸铁类型和热处理方法的理由，答案提供了具体的材料选择和热处理工艺，并隐含需要解释\"why\"的部分，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求选择特定类型的铸铁和热处理工艺，并解释原因。这需要理解铸铁的分类、性能特点及其应用场景，以及热处理工艺对材料性能的影响。虽然不涉及复杂的计算或深度机理分析，但需要对多个概念进行关联和综合分析，属于中等应用层次。 | 难度: 在选择题型内，该题目属于较高难度，原因如下：", "convertible": true, "correct_option": "gray cast iron, (as-cast) HT250, stress relief annealing", "choice_question": "Which type of cast iron and heat treatment method should be used for the machine tool bed, and why?", "conversion_reason": "The answer is a standard combination of materials and treatment methods, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Gray cast iron (HT250), stress relief annealing", "B": "Ductile cast iron (QT600-3), quenching and tempering", "C": "White cast iron (Ni-Hard), solution treatment", "D": "Malleable cast iron (KTH350-10), normalizing" }, "correct_answer": "A", "explanation": "Gray cast iron (HT250) with stress relief annealing is the correct choice because it provides excellent vibration damping capacity, good machinability, and dimensional stability required for machine tool beds. Option B is a cognitive bias trap using the superior tensile strength of ductile iron which is unnecessary for this application. Option C exploits professional intuition by suggesting a wear-resistant material that lacks damping properties. Option D is a multi-level verification trap combining a correct heat treatment method with an inappropriate material type.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1127, "question": "Packing density", "answer": "Packing density: It represents the ratio of the volume occupied by atoms in a unit cell to the volume of the unit cell, and is a parameter to measure the tightness of atomic arrangement. The higher the packing density, the tighter the atomic arrangement in the crystal, and the denser the crystal structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Packing density\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即对\"packing density\"的定义及其在晶体结构中的意义的解释。这属于基础概念记忆的范畴，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生对\"packing density\"的定义、计算方式及其在晶体结构中的意义有清晰的理解。题目不仅要求记忆定义，还需要理解这一参数如何反映原子排列的紧密程度，属于概念解释和描述的层次。相比简单定义简答（等级1），该题目需要更深入的概念掌握，但尚未达到复杂概念体系阐述（等级3）的程度。", "convertible": true, "correct_option": "It represents the ratio of the volume occupied by atoms in a unit cell to the volume of the unit cell, and is a parameter to measure the tightness of atomic arrangement. The higher the packing density, the tighter the atomic arrangement in the crystal, and the denser the crystal structure.", "choice_question": "Which of the following best describes packing density?", "conversion_reason": "The answer is a standard definition of a scientific term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It represents the ratio of the volume occupied by atoms in a unit cell to the volume of the unit cell, and is a parameter to measure the tightness of atomic arrangement.", "B": "It is defined as the mass of atoms per unit volume of a crystal structure, commonly expressed in g/cm³.", "C": "It describes the percentage of theoretical density achieved in a polycrystalline material after sintering.", "D": "It refers to the maximum possible coordination number of atoms in a perfect crystalline lattice." }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines packing density in crystallography. Option B confuses packing density with theoretical density by introducing mass-based definition. Option C exploits sintering terminology to mislead about single crystal properties. Option D strategically substitutes coordination number concept while maintaining lattice-related terminology to create a plausible-sounding distractor.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4080, "question": "[e] Beryllium metal is commonly used as an alloying agent in copper metal.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（Beryllium metal is commonly used as an alloying agent in copper metal），并要求判断其正误（答案：T），符合判断题的特征。 | 知识层次: 题目考查对铍金属作为铜合金化剂这一基本事实的记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆铍金属常用作铜合金的添加剂这一基础事实即可作答，无需理解或分析复杂概念，解题步骤简单直接。", "convertible": true, "correct_option": "T", "choice_question": "[e] Beryllium metal is commonly used as an alloying agent in copper metal.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect brittleness with zero plastic deformation under any loading conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain advanced ceramics (like transformation-toughened zirconia) can exhibit limited plastic deformation under specific conditions. The use of 'all' and 'any' makes this statement false, as it ignores exceptions and temperature/loading condition dependencies.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3764, "question": "Calculate the volume of the cylindrical riser required to prevent shrinkage in a 1 in. x 6 in. x 6 in. casting if the H/D of the riser is 1.0.", "answer": "the volume of the riser must be at least 8.95 in^3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算圆柱形冒口的体积），并且答案是一个具体的数值结果（8.95 in^3），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括理解铸造收缩的原理、计算铸件的体积以及确定冒口的尺寸比例（H/D=1.0），并应用相关公式计算冒口的体积。这需要概念关联和综合分析能力，而不仅仅是简单的公式套用或基础概念记忆。 | 难度: 在选择题中属于中等偏上难度，需要理解圆柱形冒口的设计原理（H/D比）、体积计算与铸件收缩补偿之间的关系。题目要求进行多步计算（确定冒口尺寸、计算体积）并综合判断冒口体积是否满足铸件补缩需求，涉及中等应用层次的知识关联和综合分析能力。虽然题目提供了H/D比简化了部分计算，但仍需正确应用几何公式和工程判断，在选择题型中属于需要一定计算和推理能力的题目。", "convertible": true, "correct_option": "the volume of the riser must be at least 8.95 in^3", "choice_question": "What is the volume of the cylindrical riser required to prevent shrinkage in a 1 in. x 6 in. x 6 in. casting if the H/D of the riser is 1.0?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.95 in^3", "B": "6.00 in^3", "C": "10.37 in^3", "D": "12.57 in^3" }, "correct_answer": "A", "explanation": "The correct answer is A (8.95 in^3) because it accounts for the required riser volume based on the casting's volume and the H/D ratio of 1.0. Option B (6.00 in^3) is a cognitive bias trap - it matches the casting's smallest dimension but ignores the actual volume calculation. Option C (10.37 in^3) is a professional intuition trap - it uses the correct formula but incorrectly assumes a higher safety factor. Option D (12.57 in^3) is a multi-level verification trap - it calculates the volume of a cylinder with diameter equal to the casting's longest dimension, which is inappropriate for this scenario.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 830, "question": "Indicate the first main mechanism of alloy strengthening and explain its strengthening reason", "answer": "Solid solution strengthening. The alloy element atoms dissolved in the lattice interstices or nodes, due to their size differing from the matrix atoms, generate a certain stress field that hinders dislocation movement; Cottrell atmospheres and Suzuki atmospheres, the former being interstitial atoms preferentially distributed in the tensile stress region of edge dislocations in BCC metals, producing a pinning effect on dislocations, the latter being alloy elements preferentially distributed in the stacking fault region of extended dislocations in FCC metals, reducing stacking fault energy, expanding the stacking fault region, making the slip of extended dislocations more difficult.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释合金强化的第一种主要机制及其强化原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释合金强化的主要机制及其强化原因，涉及固溶强化、位错运动阻碍、Cottrell气团和Suzuki气团等复杂概念，需要综合运用材料科学知识进行机理分析和解释。思维过程要求深入理解位错与溶质原子的相互作用，以及不同晶体结构中的强化机制，属于复杂分析和机理解释的层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目不仅要求识别合金强化的主要机制（固溶强化），还需要深入解释其强化原理，包括应力场的产生、Cottrell气团和Suzuki气团的作用机制，以及它们对不同晶体结构（BCC和FCC）中位错运动的影响。这需要考生具备深厚的材料科学知识，能够综合运用多个复杂概念，并进行机理层面的深入分析。在选择题型中，这种要求全面理解并解释复杂现象的问题属于最高难度等级。", "convertible": true, "correct_option": "Solid solution strengthening", "choice_question": "Which of the following is the first main mechanism of alloy strengthening?", "conversion_reason": "The answer is a standard term (Solid solution strengthening) which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the identification of the mechanism.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening", "B": "Grain boundary strengthening", "C": "Dislocation multiplication", "D": "Precipitation hardening" }, "correct_answer": "A", "explanation": "Solid solution strengthening is the first main mechanism as it occurs immediately upon alloying due to atomic size mismatch. Option B exploits the common misconception that grain boundaries are the primary initial strengthening mechanism. Option C targets the intuitive but incorrect association with dislocation movement. Option D uses a valid but later-stage strengthening mechanism to create temporal confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3689, "question": "A 0.001 -in. BCC iron foil is used to separate a high hydrogen gas from a low hydrogen gas at 650^{\\circ} C .5 × 10^{8} H atoms / {cm}^{3} are in equilibrium with the hot side of the foil, while 2 × 10^{3} H atoms / {cm}^{3} are in equilibrium with the cold side. Determine the flux of hydrogen through the foil.", "answer": "0.33 × 10^{8} h atoms/cm^2·s", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定氢通过铁箔的流量，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用菲克第一定律进行多步计算，涉及浓度梯度确定、扩散系数计算（需查阅BCC铁中氢的扩散系数数据）以及单位换算等综合分析过程，但不需要复杂的机理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散通量的概念，掌握菲克第一定律的应用，并进行多步骤计算。题目涉及浓度梯度、扩散系数（隐含）和厚度换算，需要综合分析多个变量才能得出正确选项。虽然题目提供了部分参数，但考生仍需具备将理论知识与实际计算结合的能力。", "convertible": true, "correct_option": "0.33 × 10^{8} h atoms/cm^2·s", "choice_question": "A 0.001 -in. BCC iron foil is used to separate a high hydrogen gas from a low hydrogen gas at 650^{\\circ} C .5 × 10^{8} H atoms / {cm}^{3} are in equilibrium with the hot side of the foil, while 2 × 10^{3} H atoms / {cm}^{3} are in equilibrium with the cold side. The flux of hydrogen through the foil is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.33 × 10^{8} H atoms/cm^2·s", "B": "1.65 × 10^{8} H atoms/cm^2·s", "C": "0.33 × 10^{6} H atoms/cm^2·s", "D": "1.65 × 10^{6} H atoms/cm^2·s" }, "correct_answer": "A", "explanation": "正确答案A是通过菲克第一定律正确计算得到的氢原子通量，考虑了浓度梯度和扩散系数。干扰项B错误地使用了算术平均浓度而非浓度差计算通量，这是常见认知偏差。干扰项C正确计算了浓度差但错误转换了单位（英寸到厘米），这是单位陷阱。干扰项D结合了B的错误计算方法和C的单位错误，是多层次验证陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3086, "question": "In order to achieve high strength in composite materials, the elastic modulus of the fibers must be very high.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对复合材料中纤维弹性模量与强度关系的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅考察对复合材料强度与纤维弹性模量关系这一基础概念的简单记忆，无需深入理解或分析。正确选项直接对应教材中的基本原理陈述，属于最基础的选择题难度等级。", "convertible": true, "correct_option": "√", "choice_question": "In order to achieve high strength in composite materials, the elastic modulus of the fibers must be very high.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All composite materials with high fiber elastic modulus exhibit superior fatigue resistance compared to those with lower modulus fibers.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While high elastic modulus fibers generally contribute to stiffness, fatigue resistance depends on multiple factors including fiber-matrix interface strength, fiber alignment, and matrix properties. Some lower modulus fiber composites may exhibit better fatigue resistance due to better energy dissipation mechanisms or improved interfacial bonding.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2024, "question": "A ceramic insulator contains $1\\\\%$ (by volume) of pores after sintering, with the pores being cubes of side length $13.7\\\\mathrm{mm}$. If during the manufacturing process, the powder can be pressed to contain $24\\\\%$ pores, what should the size of the mold be?", "answer": "The size of the mold should be $l=15.0\\\\mathrm{~mm}$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定模具的尺寸。答案给出了具体的数值结果，表明这是一个计算题。 | 知识层次: 题目需要进行多步计算，涉及孔隙率和尺寸变化的概念关联，需要综合分析初始和最终状态的关系，并应用相关公式进行计算。虽然不涉及复杂的机理分析或创新设计，但思维过程要求高于简单的公式套用。 | 难度: 在选择题中属于中等偏上难度，需要理解孔隙率与尺寸变化的关系，进行多步计算（包括体积百分比转换和立方体尺寸计算），并综合分析制造工艺参数对最终尺寸的影响。虽然题目提供了关键参数，但解题过程涉及多个概念关联和计算步骤，比单纯的概念选择题更复杂。", "convertible": true, "correct_option": "15.0 mm", "choice_question": "A ceramic insulator contains $1\\%$ (by volume) of pores after sintering, with the pores being cubes of side length $13.7\\mathrm{mm}$. If during the manufacturing process, the powder can be pressed to contain $24\\%$ pores, what should the size of the mold be?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "15.0 mm", "B": "13.7 mm", "C": "17.2 mm", "D": "12.5 mm" }, "correct_answer": "A", "explanation": "正确答案A基于体积分数变化计算：初始24%孔隙率压缩至1%时，线性尺寸变化为(24/1)^(1/3)=2.884，因此模具尺寸应为13.7mm/2.884≈15.0mm。干扰项B利用原始孔隙尺寸的直觉误导；C错误地使用加法而非立方根关系；D基于错误的反比计算。AI容易忽略烧结过程中的非线性尺寸变化关系。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1112, "question": "The Burgers vector of edge dislocations and screw dislocations changes with the direction vector of the dislocation line.", "answer": "Wrong! The Burgers vector of an edge dislocation is perpendicular to the direction vector of the dislocation line; the Burgers vector of a screw dislocation is parallel to the direction vector of the dislocation line.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目陈述了一个观点（The Burgers vector of edge dislocations and screw dislocations changes with the direction vector of the dislocation line），并要求判断其正确性。答案明确指出了该陈述是错误的，并给出了正确的解释。这符合判断题的特征，即判断陈述的对错。 | 知识层次: 题目考查对位错类型及其Burgers向量方向的基本概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（位错的Burgers矢量方向），但需要考生理解并区分两种不同类型位错（刃型位错和螺型位错）的Burgers矢量与位错线方向的关系。这比单纯记忆定义（等级1）要求更高，但尚未达到需要分析复杂概念陈述（等级3）的程度。", "convertible": true, "correct_option": "Wrong! The Burgers vector of an edge dislocation is perpendicular to the direction vector of the dislocation line; the Burgers vector of a screw dislocation is parallel to the direction vector of the dislocation line.", "choice_question": "The Burgers vector of edge dislocations and screw dislocations changes with the direction vector of the dislocation line.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All phase transformations in metallic materials exhibit a nucleation and growth mechanism.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many phase transformations follow nucleation and growth, some diffusionless transformations (like martensitic transformations) occur through shear mechanisms without nucleation. The absolute term 'all' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1288, "question": "The first law of diffusion applies to steady-state diffusion, and its mathematical expression can be written as (19)", "answer": "J=-Ddc/dx", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求写出扩散第一定律的数学表达式，需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目考查菲克第一定律的基本概念和数学表达式的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆菲克第一定律的基本数学表达式，属于基础概念记忆的范畴。题目直接给出了正确选项，无需进行复杂的分析或推理，因此难度等级为1。", "convertible": true, "correct_option": "J=-Ddc/dx", "choice_question": "The first law of diffusion applies to steady-state diffusion, and its mathematical expression can be written as:", "conversion_reason": "The answer is a standard mathematical expression, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "J=-Ddc/dx", "B": "J=Ddc/dx", "C": "J=-D(dc/dx)^2", "D": "J=-D(dc/dt)" }, "correct_answer": "A", "explanation": "The correct answer is A because Fick's first law states that the diffusion flux (J) is proportional to the negative gradient of concentration (dc/dx), with the proportionality constant being the diffusion coefficient (D). Option B is incorrect because it omits the negative sign, which is crucial for indicating diffusion occurs from high to low concentration. Option C introduces a squared term, which is a common mistake when confusing Fick's first law with more complex diffusion equations. Option D is incorrect because it uses time derivative (dc/dt) instead of spatial derivative (dc/dx), which is a typical error when mixing up Fick's first and second laws.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1838, "question": "What factors does the concentration of component defects mainly depend on?", "answer": "Solid solubility", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释影响组分缺陷浓度的主要因素，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查的是对组分缺陷浓度主要依赖因素的基本概念记忆，即固溶度（solid solubility），属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，要求考生回忆\"组分缺陷浓度主要取决于什么\"这一简单定义。正确选项\"固溶度\"是材料科学中的基本术语，无需复杂推理或概念比较，属于最基础的定义简答级别。", "convertible": true, "correct_option": "Solid solubility", "choice_question": "What does the concentration of component defects mainly depend on?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solubility", "B": "Crystallographic orientation", "C": "Dislocation density", "D": "Grain boundary energy" }, "correct_answer": "A", "explanation": "The correct answer is A because the concentration of component defects is fundamentally determined by the solid solubility limit in the host lattice. Option B exploits the cognitive bias that crystallographic orientation affects defect distribution (true for dislocations but not component defects). Option C is a professional intuition trap, as dislocation density influences mechanical properties but not stoichiometric defect concentrations. Option D is a multi-level verification trap, as grain boundary energy affects diffusion but not the equilibrium defect concentration.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1505, "question": "How do the plasticity and toughness of a metal with finer grains compare to the same metal with coarser grains", "answer": "Better", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释金属晶粒尺寸对塑性和韧性的影响，需要文字论述，而非选择、判断或计算。答案\"Better\"过于简略，通常简答题需要更详细的解释。 | 知识层次: 题目要求比较金属晶粒细化对塑性和韧性的影响，需要理解晶粒尺寸与力学性能之间的关系，并进行综合分析。这涉及多个概念的关联和中等程度的推理分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解金属晶粒尺寸对塑性和韧性的影响这一概念，并进行比较分析。虽然题目给出了正确选项，但学生需要掌握晶粒细化对金属力学性能的影响机制，并能将这一知识应用到具体比较情境中。这涉及到材料科学中微观结构与宏观性能关系的理解，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "Better", "choice_question": "How do the plasticity and toughness of a metal with finer grains compare to the same metal with coarser grains?", "conversion_reason": "The answer is a standard term that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Better plasticity but lower toughness due to increased grain boundary sliding", "B": "Worse plasticity but higher toughness due to dislocation pile-up effects", "C": "Better in both properties due to grain boundary strengthening mechanisms", "D": "No significant difference as grain size only affects hardness" }, "correct_answer": "C", "explanation": "The correct answer is C because finer grains increase both plasticity and toughness through grain boundary strengthening (Hall-Petch effect) and more uniform deformation. Option A uses a real phenomenon (grain boundary sliding) but misapplies it to toughness. Option B reverses the actual dislocation dynamics in finer grains. Option D is a common oversimplification that ignores grain size's multifaceted effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4709, "question": "What is the composition, in atom percent, of an alloy that consists of 92.5 wt% \\mathrm{Ag} and 7.5 wt% Cu ?", "answer": "the composition of the alloy is 87.9 \\text{ at}% \\text{ ag} and 12.1 \\text{ at}% \\text{ cu}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（如重量百分比转换为原子百分比）来得出具体的数值结果，答案也是以数值形式呈现的。 | 知识层次: 题目需要进行基本的数值计算和公式应用，涉及原子百分比和重量百分比之间的转换，属于直接套用基本公式的简单应用。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用原子百分比和重量百分比之间的转换公式，但计算步骤相对直接，仅涉及基本代数运算和单位转换。不需要复杂的逻辑推理或多步骤的综合计算，因此难度等级为2。", "convertible": true, "correct_option": "87.9 at% Ag and 12.1 at% Cu", "choice_question": "What is the composition, in atom percent, of an alloy that consists of 92.5 wt% Ag and 7.5 wt% Cu?", "conversion_reason": "The answer is a specific numerical result, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "87.9 at% Ag and 12.1 at% Cu", "B": "92.5 at% Ag and 7.5 at% Cu", "C": "85.4 at% Ag and 14.6 at% Cu", "D": "89.7 at% Ag and 10.3 at% Cu" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算原子百分比得出的，考虑了Ag和Cu的原子量差异。干扰项B直接使用重量百分比，利用了AI可能忽略单位转换的认知偏差。干扰项C设计为接近但错误的值，利用了AI在数值估算时的直觉误差。干扰项D基于部分正确的计算步骤但引入微小误差，挑战AI的多层次验证能力。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 772, "question": "Fick's first law is applicable to solving unstable diffusion problems", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（答案为×表示错误），符合判断题的特征 | 知识层次: 题目考查对Fick's first law适用范围这一基本概念的简单记忆和理解，不涉及复杂应用或分析 | 难度: 该题目属于基础概念正误判断题，仅需记忆Fick第一定律的适用范围即可作答，无需理解或分析复杂概念，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "×", "choice_question": "Fick's first law is applicable to solving unstable diffusion problems", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The Hall-Petch relationship holds true for nanocrystalline materials with grain sizes below 10 nm", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "The Hall-Petch relationship describes how yield strength increases with decreasing grain size in polycrystalline materials, but this relationship breaks down for nanocrystalline materials with grain sizes below a critical value (typically around 10-20 nm). Below this threshold, grain boundary sliding and other mechanisms become dominant, causing an inverse Hall-Petch effect where strength decreases with further grain size reduction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1031, "question": "Crystal face family", "answer": "Crystal face family: Groups of equivalent crystal faces with the same symmetrical relationship (atomic arrangement and distribution, interplanar spacing) are called a crystal face family, denoted by hll.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Crystal face family\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查晶体学中晶面族的基本定义和符号表示，属于基础概念的记忆和理解范畴，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆基础概念的定义和分类，属于最基础的知识层次。正确选项直接给出了\"crystal face family\"的定义和表示方法，不需要进行任何解释或复杂的概念分析。这种题目只需要考生记住基本定义即可作答，属于选择题中最简单的类型。", "convertible": true, "correct_option": "Groups of equivalent crystal faces with the same symmetrical relationship (atomic arrangement and distribution, interplanar spacing) are called a crystal face family, denoted by hll.", "choice_question": "Which of the following correctly describes a crystal face family?", "conversion_reason": "The answer is a standard definition of a crystal face family, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Groups of equivalent crystal faces with the same symmetrical relationship (atomic arrangement and distribution, interplanar spacing) are called a crystal face family, denoted by {hkl}", "B": "A set of crystal faces with identical Miller indices but different surface energies, forming distinct thermodynamic states", "C": "All possible crystallographic planes that can be derived from a single plane by symmetry operations, regardless of their atomic density", "D": "The collection of all low-index crystal faces ({100}, {110}, {111}) in a given crystal structure that dominate surface properties" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a crystal face family as equivalent faces related by symmetry with identical atomic arrangements and spacings, properly denoted by {hkl} in braces. Option B introduces a thermodynamic misconception by suggesting different surface energies within a family. Option C is incorrect because it omits the critical requirement of equivalent atomic arrangements. Option D wrongly limits the concept to only low-index faces, ignoring higher-index families. The distractors exploit common misconceptions about symmetry equivalence and surface dominance that even advanced AI might conflate.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2945, "question": "The relationship between the growth velocity (vg) of a certain crystal during solidification and the dynamic undercooling (ΔTx) at the liquid-solid interface front is vg proportional to ΔTx^2. This crystal belongs to which growth mechanism? (A) Continuous growth (B) Growth via screw dislocations (C) Two-dimensional nucleation", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从给定的选项（A、B、C）中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对晶体生长机制的理解和应用，需要将生长速度与动态过冷度的关系与不同的生长机制联系起来进行分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要理解晶体生长机制中的动态过冷与生长速度的关系，并能够将数学关系（vg ∝ ΔTx^2）与具体的生长机制（如螺位错生长）联系起来。此外，还需要对连续生长、二维成核等其他机制有一定的了解，才能正确选择。这需要多步的概念关联和综合分析，超出了基础记忆或简单理解的层次。", "convertible": true, "correct_option": "B", "choice_question": "The relationship between the growth velocity (vg) of a certain crystal during solidification and the dynamic undercooling (ΔTx) at the liquid-solid interface front is vg proportional to ΔTx^2. This crystal belongs to which growth mechanism?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Continuous growth", "B": "Growth via screw dislocations", "C": "Two-dimensional nucleation", "D": "Lateral growth with kinetic coefficient" }, "correct_answer": "B", "explanation": "The quadratic relationship (vg ∝ ΔTx^2) is characteristic of growth via screw dislocations (B), where growth occurs at spiral steps. Continuous growth (A) would show linear dependence (vg ∝ ΔTx), while two-dimensional nucleation (C) would exhibit exponential dependence. Option D is a distractor combining correct kinetic terminology with incorrect growth mode, exploiting AI's tendency to associate coefficients with linear relationships.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1912, "question": "Normal spinel structure", "answer": "5. Normal spinel structure: It belongs to the cubic crystal system, in which oxygen ions can be regarded as arranged in cubic close packing, divalent cations A fill one-eighth of the tetrahedral voids, and trivalent cations B fill half of the octahedral voids.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对Normal spinel structure进行文字解释和论述，答案提供了详细的晶体结构描述，属于简答题的特征。 | 知识层次: 题目考查对Normal spinel结构的基本概念记忆，包括晶体系统、离子排列方式以及阳离子占据空隙的类型和比例，属于基础概念的记忆和理解层面。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及晶体结构的基本概念，但需要考生理解和记忆多个关键点，如立方晶系、氧离子的立方密堆积排列、二价和三价阳离子占据的间隙位置等。这些知识点虽然基础，但需要一定的概念整合能力，属于概念解释和描述的层次。", "convertible": true, "correct_option": "It belongs to the cubic crystal system, in which oxygen ions can be regarded as arranged in cubic close packing, divalent cations A fill one-eighth of the tetrahedral voids, and trivalent cations B fill half of the octahedral voids.", "choice_question": "Which of the following correctly describes the normal spinel structure?", "conversion_reason": "The answer is a standard description of the normal spinel structure, which can be converted into a multiple-choice question format by presenting it as one of several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It belongs to the cubic crystal system, in which oxygen ions can be regarded as arranged in cubic close packing, divalent cations A fill one-eighth of the tetrahedral voids, and trivalent cations B fill half of the octahedral voids.", "B": "It belongs to the hexagonal crystal system, with oxygen ions in hexagonal close packing, divalent cations occupying all tetrahedral voids, and trivalent cations in one-third of octahedral voids.", "C": "It belongs to the cubic crystal system, with oxygen ions in cubic close packing, but with trivalent cations filling tetrahedral voids and divalent cations in octahedral voids (inverse spinel).", "D": "It belongs to the tetragonal crystal system, with oxygen ions in body-centered cubic arrangement, divalent cations in one-fourth of tetrahedral voids, and trivalent cations in three-fourths of octahedral voids." }, "correct_answer": "A", "explanation": "The correct answer A describes the normal spinel structure accurately, with cubic close packing of oxygen ions and specific void filling ratios. Option B incorrectly assigns a hexagonal system and wrong void occupation ratios. Option C describes an inverse spinel structure, not normal. Option D introduces a non-existent tetragonal variant with incorrect void filling statistics, exploiting the AI's potential confusion with other crystal systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 351, "question": "(Taking the face-centered cubic unit cell as an example) What are the common parameters used to describe the characteristics of a crystal structure (unit cell)? What is the packing density of an FCC unit cell?", "answer": "Packing density 0.74.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求描述晶体结构的常见参数，并计算FCC晶胞的堆积密度，需要文字解释和数值计算相结合的回答方式。 | 知识层次: 题目要求描述晶体结构（晶胞）的常见参数，并计算FCC晶胞的堆积密度。虽然需要理解晶体结构的基本概念，但主要涉及基本公式的应用和简单计算，属于直接套用和简单应用层次。 | 难度: 在选择题中属于简单应用难度，题目直接考察对FCC晶胞堆积密度的记忆和基本公式应用，无需复杂计算或分析，仅需正确识别和选择给定的正确选项。", "convertible": true, "correct_option": "0.74", "choice_question": "What is the packing density of an FCC unit cell?", "conversion_reason": "The answer to the question is a specific numerical value (0.74), which can be presented as one of the options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.74", "B": "0.68", "C": "0.52", "D": "0.82" }, "correct_answer": "A", "explanation": "The correct answer is A (0.74) because in an FCC unit cell, the packing density is calculated as the ratio of the volume occupied by atoms to the total volume of the unit cell, which for FCC is 74%. Option B (0.68) is the packing density of a BCC structure, exploiting confusion between common crystal structures. Option C (0.52) represents the packing density of a simple cubic structure, another common but incorrect intuition. Option D (0.82) is a high-value trap that might appeal to those overestimating the efficiency of atomic packing in close-packed structures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4645, "question": "What type(s) of bonding would be expected for calcium fluoride (CaF2)?", "answer": "For CaF2, the bonding is predominantly ionic (but with some slight covalent character) on the basis of the relative positions of Ca and F in the periodic table.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释CaF2的键合类型，需要文字论述和解释，而不是从选项中选择或简单判断对错。答案也提供了详细的解释说明，符合简答题的特征。 | 知识层次: 题目考查对化学键类型（离子键和共价键）的基本概念记忆和理解，以及根据元素在周期表中的位置判断键型的能力，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目要求考生理解并描述钙氟化物的主要键合类型（离子键）以及次要特征（部分共价性），这属于概念解释和描述的层次。虽然需要记忆元素在周期表中的相对位置，但不需要复杂的分析或比较多个概念体系，因此属于中等难度。", "convertible": true, "correct_option": "predominantly ionic (but with some slight covalent character)", "choice_question": "What type(s) of bonding would be expected for calcium fluoride (CaF2)?", "conversion_reason": "The answer is a standard description of the bonding type for calcium fluoride, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Predominantly ionic with slight covalent character", "B": "Pure ionic bonding with no covalent contribution", "C": "Metallic bonding due to calcium's free electrons", "D": "Network covalent bonding forming continuous 3D structure" }, "correct_answer": "A", "explanation": "Correct answer is A because CaF2 is primarily ionic but shows slight covalent character due to polarization of F- ions. B is incorrect as it ignores the well-documented partial covalency in ionic compounds. C exploits the misconception that all metals form metallic bonds in compounds. D is a trap based on superficial similarity to network covalent solids like SiO2.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1950, "question": "What are the application conditions of the first law of diffusion?", "answer": "The application condition of the first law of diffusion is steady-state diffusion, that is, diffusion independent of time.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释第一扩散定律的应用条件，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对扩散第一定律应用条件的基本概念记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆和识别第一扩散定律的基本应用条件（稳态扩散），属于最基础的定义性知识，无需解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Steady-state diffusion, that is, diffusion independent of time.", "choice_question": "What is the application condition of the first law of diffusion?", "conversion_reason": "The answer is a standard concept and can be converted into a multiple-choice question format by presenting the correct option among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Steady-state diffusion with constant concentration gradient", "B": "Non-steady state diffusion with time-dependent flux", "C": "Diffusion in systems with chemical reactions occurring", "D": "All diffusion processes regardless of boundary conditions" }, "correct_answer": "A", "explanation": "The first law of diffusion (Fick's first law) strictly applies to steady-state diffusion where the concentration gradient is constant and independent of time. Option B is incorrect because it describes non-steady state diffusion governed by Fick's second law. Option C is a trap using the common misconception that chemical reactions don't affect diffusion laws - in reality reactions create non-steady state conditions. Option D exploits the AI's tendency to overgeneralize by suggesting universal applicability, ignoring the fundamental steady-state requirement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2616, "question": "The atomic number of copper is 29, its relative atomic mass is 63.54, and it has two isotopes, Cu63 and Cu65. Calculate the percentage content of the two copper isotopes.", "answer": "$A{\\\\mathrm{r}}=63.54=63x+65\\\\times(1-x);\\\\quad x={\\\\frac{65-63.54}{2}}=0.73\\\\rightarrow73\\\\mathcal{V}_{0}\\\\left(\\\\mathrm{Cu}^{\\\\mathrm{63}}\\\\right);$ $1-x=0.27\\\\substack{\\\\rightarrow27\\\\%(\\\\mathrm{Cu}^{65})}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解两种铜同位素的百分比含量，答案展示了具体的计算过程和结果。 | 知识层次: 题目主要涉及基本公式应用和简单计算，通过给定的原子质量和同位素信息直接套用公式求解百分比含量，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然涉及同位素百分比的计算，但解题步骤明确且直接，只需套用给定的相对原子质量公式并进行简单的代数运算即可得出答案。不需要复杂的推理或多步骤的公式组合，因此难度等级为2。", "convertible": true, "correct_option": "73% Cu63 and 27% Cu65", "choice_question": "The atomic number of copper is 29, its relative atomic mass is 63.54, and it has two isotopes, Cu63 and Cu65. What is the percentage content of the two copper isotopes?", "conversion_reason": "The calculation yields a specific and definitive answer (73% Cu63 and 27% Cu65), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "73% Cu63 and 27% Cu65", "B": "65% Cu63 and 35% Cu65", "C": "50% Cu63 and 50% Cu65", "D": "63% Cu63 and 37% Cu65" }, "correct_answer": "A", "explanation": "The correct answer is calculated by setting up the equation: 63x + 65(1-x) = 63.54, solving for x gives 0.73 for Cu63. Option B reverses the percentages based on isotope numbers, creating a cognitive bias. Option C is a naive equal distribution that ignores the mass difference. Option D uses the relative atomic mass directly as percentages, a common unit confusion trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4416, "question": "Give the approximate minimum temperature at which it is possible to austenitize a 0.95 wt% C iron-carbon alloy during a normalizing heat treatment.", "answer": "At least 840°C (1545°F)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从多个选项中选择或进行复杂的计算。虽然答案是一个数值，但解答过程需要基于材料科学知识（如铁碳相图）进行解释和判断，属于需要简要论述的简答题类型。 | 知识层次: 题目需要理解铁碳合金相图，并能够根据给定的碳含量（0.95 wt% C）确定奥氏体化温度。这涉及到多步分析和概念关联，包括相变温度和合金成分的关系，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解铁碳相图的基本概念，能够根据合金成分（0.95 wt% C）定位到共析点附近，并知道奥氏体化温度必须高于Acm线。虽然不需要复杂的计算，但需要将多个概念关联起来进行综合分析。", "convertible": true, "correct_option": "At least 840°C (1545°F)", "choice_question": "What is the approximate minimum temperature at which it is possible to austenitize a 0.95 wt% C iron-carbon alloy during a normalizing heat treatment?", "conversion_reason": "The answer is a specific temperature value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "840°C (1545°F)", "B": "727°C (1340°F)", "C": "912°C (1674°F)", "D": "768°C (1414°F)" }, "correct_answer": "A", "explanation": "The correct answer is A (840°C) because this is the temperature where the 0.95 wt% C alloy crosses the A3 line on the Fe-C phase diagram, the minimum required for complete austenitization. Option B (727°C) is the eutectoid temperature, a common but incorrect guess. Option C (912°C) is the γ-Fe to δ-Fe transformation temperature for pure iron, irrelevant here. Option D (768°C) is the Curie temperature, which affects magnetic properties but not phase transformation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1575, "question": "4. Constitutional supercooling", "answer": "During crystallization, the phenomenon where a supercooled zone forms in the liquid phase near the solid-liquid interface due to the redistribution of components between the solid and liquid phases is called constitutional supercooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Constitutional supercooling\"这一现象进行文字解释和论述，答案提供了详细的定义和解释，符合简答题的特征。 | 知识层次: 题目考查对\"Constitutional supercooling\"这一基本概念的定义和现象描述，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确理解并描述\"constitutional supercooling\"这一现象的定义和形成原因。这比简单识别定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "During crystallization, the phenomenon where a supercooled zone forms in the liquid phase near the solid-liquid interface due to the redistribution of components between the solid and liquid phases is called constitutional supercooling.", "choice_question": "Which of the following describes constitutional supercooling?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as the correct option among several plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "During crystallization, a supercooled zone forms in the liquid phase near the solid-liquid interface due to component redistribution", "B": "Rapid cooling below the glass transition temperature without crystallization", "C": "Thermal gradient-induced undercooling ahead of a solidification front", "D": "Simultaneous occurrence of thermal and solute gradient effects during solidification" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely describes constitutional supercooling where solute redistribution creates composition-dependent undercooling. Option B is a trap describing glass formation, exploiting confusion between different undercooling phenomena. Option C uses thermal gradient terminology which is incorrect for constitutional supercooling, targeting confusion between thermal and solutal effects. Option D combines correct elements but inaccurately, creating a plausible-sounding but incorrect definition that might fool systems relying on pattern matching.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 724, "question": "The flow of clay slurry belongs to plastic flow", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（The flow of clay slurry belongs to plastic flow），要求判断其正确性（√），这是典型的判断题形式。答案只需判断对错，不需要选择或解释。 | 知识层次: 题目考查对粘土浆流动性质的基本概念记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念正误判断题，仅需记忆粘土浆的流动类型属于塑性流动这一基本定义即可作答。在选择题型中，这类仅需识别基础概念正误的题目属于最低难度等级。", "convertible": true, "correct_option": "√", "choice_question": "The flow of clay slurry belongs to plastic flow", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All polymer solutions exhibit Newtonian flow behavior under shear stress", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because most polymer solutions exhibit non-Newtonian behavior, particularly shear-thinning (pseudoplastic) flow. The statement uses an absolute term 'all' which is incorrect. Only dilute polymer solutions might approach Newtonian behavior, while concentrated solutions and melts typically show complex rheological properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 603, "question": "In the Fe-Fe3C phase diagram, what is the carbon content below which the material is considered steel?", "answer": "2.11%C", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的数值（2.11%C），不需要从多个选项中选择，也不涉及判断对错或复杂的计算过程，属于简答题类型。 | 知识层次: 题目考查对Fe-Fe3C相图中钢的定义这一基本概念的记忆和理解，无需复杂分析或计算。 | 难度: 在选择题型中，该题目仅考察对Fe-Fe3C相图中钢的定义这一基础概念的记忆，不需要任何解释或分析步骤。学生只需回忆\"钢的碳含量上限是2.11%\"这一简单事实即可作答，属于最基础的定义性知识考查。", "convertible": true, "correct_option": "2.11%C", "choice_question": "In the Fe-Fe3C phase diagram, what is the carbon content below which the material is considered steel?", "conversion_reason": "The answer is a specific numerical value, which can be directly used as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.76%C", "B": "2.11%C", "C": "4.3%C", "D": "6.67%C" }, "correct_answer": "B", "explanation": "The correct answer is B (2.11%C) because this is the eutectoid composition where austenite transforms to pearlite. Option A (0.76%C) is a trap exploiting the eutectoid point confusion. Option C (4.3%C) is the eutectic composition, creating a phase diagram analogy trap. Option D (6.67%C) is the stoichiometric Fe3C composition, exploiting stoichiometry bias.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4807, "question": "Give the approximate temperature at which creep deformation becomes an important consideration for tin.", "answer": "for sn, -71°c or -96°f.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，不需要从多个选项中选择，也不需要判断对错或进行复杂的计算。答案是一个具体的数值，属于简答题类型。 | 知识层次: 题目考查对特定材料（锡）的蠕变温度这一基础概念的记忆，不需要复杂的应用或分析过程。 | 难度: 在选择题型中，该题目仅要求记忆锡（Sn）的蠕变变形温度这一基础概念，属于单一知识点的直接回忆。题目不涉及概念解释或复杂分析，仅需选择正确的温度数值，因此难度等级为1。", "convertible": true, "correct_option": "-71°C or -96°F", "choice_question": "At approximately what temperature does creep deformation become an important consideration for tin?", "conversion_reason": "The answer is a specific temperature value, which can be presented as a correct option among other plausible but incorrect temperature values.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-71°C", "B": "150°C", "C": "0°C", "D": "-196°C" }, "correct_answer": "A", "explanation": "正确答案A(-71°C)是锡的蠕变开始显著的温度，这是其低温特性。B(150°C)利用了常见金属蠕变温度的直觉偏差；C(0°C)利用了冰点温度的认知偏差；D(-196°C)是液氮温度，利用了极端低温条件的直觉误导。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3490, "question": "What is the role of alloying elements in high-speed steel?", "answer": "The role of alloying elements in high-speed steel: W improves the red hardness of the steel, Cr enhances hardenability, Mo reduces the second type of temper brittleness, Co delays the precipitation and aggregation of carbides during tempering, that is, improves tempering stability.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释合金元素在高速钢中的作用，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释合金元素在高速钢中的作用，涉及多个元素的特定功能及其对材料性能的影响。这需要理解合金元素的基本特性及其在材料中的相互作用，属于概念关联和综合分析的中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个合金元素（W、Cr、Mo、Co）在高速钢中的不同作用，并能将这些概念关联起来进行综合分析。题目要求考生不仅知道单个元素的作用，还要能区分不同元素对钢材性能的影响，属于中等应用层次的知识掌握。", "convertible": true, "correct_option": "W improves the red hardness of the steel, Cr enhances hardenability, Mo reduces the second type of temper brittleness, Co delays the precipitation and aggregation of carbides during tempering, that is, improves tempering stability.", "choice_question": "What is the role of alloying elements in high-speed steel?", "conversion_reason": "The answer is a standard description of the roles of various alloying elements in high-speed steel, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "W improves the red hardness of the steel, Cr enhances hardenability, Mo reduces the second type of temper brittleness, Co delays the precipitation and aggregation of carbides during tempering, that is, improves tempering stability", "B": "W increases ductility, Cr improves corrosion resistance, Mo enhances electrical conductivity, Co reduces thermal expansion coefficient", "C": "W forms stable carbides to increase hardness, Cr improves oxidation resistance, Mo enhances creep resistance, Co increases magnetic permeability", "D": "W refines grain structure, Cr lowers transformation temperature, Mo improves fatigue strength, Co increases elastic modulus" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the primary functions of alloying elements in high-speed steel. B is wrong by assigning incorrect primary functions (ductility, conductivity etc.) that contradict actual roles. C mixes partially correct carbide formation with irrelevant properties like magnetic permeability. D combines grain refinement (secondary effect) with misleading dominant characteristics. Advanced AIs may select C due to partial correctness on carbide formation, or D due to plausible-sounding but incorrect mechanical property assignments.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4109, "question": "Aramid fiber-reinforced composites have very high tensile strengths and relatively low compressive strengths.(a) True(b) False", "answer": "True. Aramid fiber-reinforced composites have very high tensile strengths and relatively low compressive strength.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其真伪（True/False），答案直接给出判断结果，符合判断题的特征 | 知识层次: 题目考查对Aramid纤维增强复合材料基本力学性能的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆Aramid fiber-reinforced composites的基本特性（高拉伸强度和低压缩强度）即可做出正确选择。题目不涉及复杂概念或需要深入理解，属于最基础的难度等级。", "convertible": true, "correct_option": "True. Aramid fiber-reinforced composites have very high tensile strengths and relatively low compressive strength.", "choice_question": "Aramid fiber-reinforced composites have very high tensile strengths and relatively low compressive strengths.(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect brittleness with zero plastic deformation under any loading conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain advanced ceramics can exhibit limited plastic deformation under specific conditions (e.g., high temperatures or hydrostatic pressure). The use of 'all' and 'any' makes this statement false, as it overlooks exceptions in specialized ceramic materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 595, "question": "In the FCC structure, when atoms are regarded as rigid spheres with radius r, the relationship between the atomic radius and the lattice constant a is", "answer": "r=a", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释FCC结构中原子半径与晶格常数之间的关系，答案需要文字说明而非选择或计算 | 知识层次: 题目考查FCC结构中原子半径与晶格常数关系的基本概念记忆，属于晶体学基础知识的直接应用，无需复杂计算或分析。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即FCC结构中原子半径与晶格常数的简单关系。正确选项直接给出了公式r=a，无需复杂推理或计算，属于基本定义简答的难度等级。", "convertible": true, "correct_option": "r=a", "choice_question": "In the FCC structure, when atoms are regarded as rigid spheres with radius r, what is the relationship between the atomic radius and the lattice constant a?", "conversion_reason": "The answer is a standard and specific relationship (r=a), which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "r = a√2 / 4", "B": "r = a / 2", "C": "r = a√3 / 4", "D": "r = a / √2" }, "correct_answer": "A", "explanation": "In FCC structure, the atoms touch along the face diagonal. The face diagonal length is a√2, which equals 4r (4 atomic radii). Therefore, r = a√2 / 4 is correct. Option B mimics the BCC structure relationship. Option C uses the body diagonal ratio which is characteristic of BCC. Option D is a plausible but incorrect derivation from the face diagonal relationship.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4426, "question": "For a ceramic compound, what are the two characteristics of the component ions that determine the crystal structure?", "answer": "The two characteristics of component ions that determine the crystal structure of a ceramic compound are: 1) the magnitude of the electrical charge on each ion, and 2) the relative sizes of the cations and anions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述陶瓷化合物中决定晶体结构的两个离子特性，答案以文字形式详细说明了两点特征，符合简答题的特征。 | 知识层次: 题目考查的是陶瓷化合物晶体结构决定因素的基本概念记忆和理解，涉及离子电荷和相对尺寸这两个基本原理，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并记忆两个关键特征（离子电荷大小和离子相对尺寸），而不仅仅是单一的定义。这比仅回答一个基本定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "The magnitude of the electrical charge on each ion and the relative sizes of the cations and anions", "choice_question": "Which two characteristics of the component ions determine the crystal structure of a ceramic compound?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The magnitude of the electrical charge on each ion and the relative sizes of the cations and anions", "B": "The electronegativity difference between ions and the coordination number of the compound", "C": "The ionic radii ratio and the thermal expansion coefficients of the constituent elements", "D": "The bond dissociation energy and the Pauling electronegativity values of the elements" }, "correct_answer": "A", "explanation": "The correct answer is A because the crystal structure of ceramic compounds is primarily determined by electrostatic interactions (charge magnitude) and geometric packing constraints (ion size ratio). Option B uses a plausible-sounding combination (electronegativity and coordination number) but coordination number is a consequence, not a determinant. Option C mixes correct ionic radii with irrelevant thermal expansion data. Option D uses authentic material properties (bond energy, electronegativity) that don't directly govern crystal structure formation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4104, "question": "Match the fiber type 'Whiskers' with its description.", "answer": "Whiskers are single crystals with extremely large length-to-diameter ratios.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求将纤维类型与其描述进行匹配，答案需要文字解释和论述，而不是从选项中选择或进行判断、计算。 | 知识层次: 题目考查对纤维类型'Whiskers'的基本定义和特性的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求匹配纤维类型与其基本定义，属于基础概念记忆的简单任务。正确选项直接给出了\"Whiskers\"的明确定义，不需要任何解释或分析步骤，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Whiskers are single crystals with extremely large length-to-diameter ratios.", "choice_question": "Which of the following best describes 'Whiskers'?", "conversion_reason": "The answer is a standard description that can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Whiskers are single crystals with extremely large length-to-diameter ratios", "B": "Whiskers are polycrystalline fibers with high surface roughness for enhanced bonding", "C": "Whiskers are amorphous ceramic fibers produced through rapid quenching", "D": "Whiskers are metallic filaments with nanoscale grain structures for improved ductility" }, "correct_answer": "A", "explanation": "The correct answer is A because whiskers are indeed defined as defect-free single crystals with exceptionally high aspect ratios. Option B exploits the common misconception that all reinforcing fibers must have surface roughness, while whiskers actually rely on their perfect crystalline structure. Option C targets confusion between whiskers and glass fibers, playing on the 'amorphous vs crystalline' dichotomy. Option D creates a metallic materials bias, using the appealing but incorrect notion of nanoscale grain structures which are irrelevant to whisker formation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2058, "question": "Point out the errors in the following concepts and correct them: (2) During metal crystallization, atoms transition from a disordered arrangement in the liquid phase to an ordered arrangement in the solid phase, which reduces the entropy of the system, making it a spontaneous process.", "answer": "Reduces the free energy of the system.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目考查对金属结晶过程中热力学基本概念的理解和记忆，主要涉及熵和自由能的变化关系，属于基础概念的记忆和简单应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（金属结晶过程中的熵变和自由能变化），但需要考生不仅记住定义，还要理解熵变和自由能变化之间的关系。题目要求识别错误概念并选择正确表述，这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。因此，该题目属于概念解释和描述层次的难度（等级2）。", "convertible": true, "correct_option": "Reduces the free energy of the system.", "choice_question": "During metal crystallization, atoms transition from a disordered arrangement in the liquid phase to an ordered arrangement in the solid phase, which reduces the entropy of the system, making it a spontaneous process. What is the correct concept that should replace the underlined part?", "conversion_reason": "The original short answer question asks for a correction to a specific concept, which can be rephrased as a multiple-choice question by providing options for the correct concept. The correct answer is a standard term that can be used as the correct option in the multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Reduces the free energy of the system", "B": "Increases the enthalpy of the system", "C": "Follows the second law of thermodynamics", "D": "Creates a metastable equilibrium state" }, "correct_answer": "A", "explanation": "The correct concept is that crystallization reduces the free energy (Gibbs free energy) of the system, which is the thermodynamic driving force for spontaneous processes. Option B is incorrect because while enthalpy may increase or decrease, it's not the determining factor for spontaneity. Option C is a cognitive bias trap - while entropy decrease seems to violate the second law, the law applies to the universe (system + surroundings), not just the system. Option D exploits professional intuition by suggesting a plausible-sounding but incorrect intermediate state concept.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2054, "question": "What is undercooling?", "answer": "The temperature difference between the actual crystallization temperature and the theoretical crystallization temperature is called undercooling (ΔT=Tm−Tn). It is required by the thermodynamic conditions of phase transformation. Only when ΔT>0 can the condition that the free energy of the solid phase is lower than that of the liquid phase be achieved. The free energy difference between the liquid and solid phases is the driving force for crystallization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"undercooling\"进行文字解释和论述，答案提供了详细的定义和原理说明，符合简答题的特征。 | 知识层次: 题目考查对undercooling这一基础概念的定义和基本原理的记忆和理解，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但正确选项不仅给出了undercooling的定义，还解释了其热力学条件和结晶驱动力，需要考生理解并描述概念背后的原理。相比仅记忆定义的等级1题目，该题要求更高层次的概念解释能力，但尚未达到需要分析复杂概念体系的等级3难度。", "convertible": true, "correct_option": "The temperature difference between the actual crystallization temperature and the theoretical crystallization temperature is called undercooling (ΔT=Tm−Tn). It is required by the thermodynamic conditions of phase transformation. Only when ΔT>0 can the condition that the free energy of the solid phase is lower than that of the liquid phase be achieved. The free energy difference between the liquid and solid phases is the driving force for crystallization.", "choice_question": "Which of the following best defines undercooling?", "conversion_reason": "The answer is a standard definition of a scientific term, which can be presented as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The temperature difference between the actual crystallization temperature and the theoretical melting temperature (ΔT=Tm−Tn), providing the driving force for solidification", "B": "The maximum possible cooling rate before nucleation occurs, as described by the TTT diagram", "C": "The temperature at which a liquid becomes metastable below its equilibrium freezing point, measured by DSC", "D": "The critical temperature gradient required to maintain planar solidification front stability" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines undercooling as the thermodynamic driving force (Tm-Tn) required for phase transformation. Option B is a TTT diagram misconception, Option C confuses undercooling with supercooling measurement, and Option D describes constitutional undercooling in directional solidification - all being common expert-level confusions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 115, "question": "For MgO, Al2O3, and Cr2O3, the radius ratios of cations to anions are 0.47, 0.36, and 0.40, respectively. Is it possible for Al2O3 and Cr2O3 to form continuous solid solutions? Why?", "answer": "Al2O3 and Cr2O3 can form continuous solid solutions, because: 1) They have the same crystal structure type, both belonging to the corundum structure. 2) (0.40-0.36)/0.40=10%<15%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Al2O3和Cr2O3能否形成连续固溶体，并给出原因。答案需要文字论述和解释，而不是简单的选择、判断或计算。 | 知识层次: 题目需要理解固溶体形成的条件，包括晶体结构类型和半径比的差异，并进行简单的计算和比较。这涉及到多个概念的关联和综合分析，但不需要复杂的推理或深度理解。 | 难度: 在选择题中属于较高难度，需要综合运用多个知识点进行分析判断。具体包括：1) 需要掌握不同氧化物的晶体结构类型知识；2) 需要理解半径比对固溶体形成的影响；3) 需要进行具体的百分比计算；4) 需要将计算结果与15%的经验规则进行比较。这些步骤涉及概念关联和综合分析能力，超出了简单记忆或单一概念应用的难度水平。", "convertible": true, "correct_option": "Al2O3 and Cr2O3 can form continuous solid solutions, because: 1) They have the same crystal structure type, both belonging to the corundum structure. 2) (0.40-0.36)/0.40=10%<15%", "choice_question": "For MgO, Al2O3, and Cr2O3, the radius ratios of cations to anions are 0.47, 0.36, and 0.40, respectively. Is it possible for Al2O3 and Cr2O3 to form continuous solid solutions? Why?", "conversion_reason": "The answer is a specific explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because their cation/anion radius ratios differ by less than 15% and they share the same crystal structure", "B": "No, because Al³⁺ and Cr³⁺ have different electronic configurations which prevent complete solubility", "C": "Only at high temperatures, as their thermal expansion coefficients differ significantly", "D": "No, because Cr2O3 has a different coordination number than Al2O3 despite similar structures" }, "correct_answer": "A", "explanation": "The correct answer is A because: 1) The radius ratio difference (10%) is below the 15% Hume-Rothery limit for solid solution formation. 2) Both oxides adopt the corundum structure. Option B is incorrect because electronic configuration doesn't prevent solubility in this case. Option C is misleading as thermal expansion differences don't fundamentally prevent solid solution formation. Option D is wrong because both cations have octahedral coordination in the corundum structure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4243, "question": "(b) Cite the difference between mechanical and annealing twins.", "answer": "Mechanical twins are produced as a result of mechanical deformation and generally occur in BCC and HCP metals. Annealing twins form during annealing heat treatments, most often in FCC metals.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释机械孪晶和退火孪晶的区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对机械孪晶和退火孪晶的基本定义和形成条件的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个专业概念（机械孪晶和退火孪晶）的比较，但正确选项已经提供了明确的定义和区分特征（形成机制和常见金属结构）。考生只需记忆并区分这两个基本概念即可作答，不需要进行复杂的推理或综合分析。这符合等级2\"概念解释和描述\"的要求，比单纯的定义记忆（等级1）稍复杂，但远未达到需要阐述复杂概念体系的等级3难度。", "convertible": true, "correct_option": "Mechanical twins are produced as a result of mechanical deformation and generally occur in BCC and HCP metals. Annealing twins form during annealing heat treatments, most often in FCC metals.", "choice_question": "Which of the following correctly describes the difference between mechanical and annealing twins?", "conversion_reason": "The answer is a standard explanation of the difference between mechanical and annealing twins, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Mechanical twins form during plastic deformation in BCC metals, while annealing twins develop during recrystallization in FCC metals", "B": "Both types of twins result from shear deformation, but mechanical twins occur at lower temperatures than annealing twins", "C": "Annealing twins are always larger than mechanical twins due to their formation during high-temperature processing", "D": "Mechanical twins require specific crystallographic orientations, whereas annealing twins form randomly during grain growth" }, "correct_answer": "A", "explanation": "Correct answer A precisely distinguishes the formation mechanisms (deformation vs heat treatment) and typical crystal structures (BCC/HCP vs FCC) for each twin type. Distractors employ multiple cognitive traps: B falsely suggests both result from shear deformation (only mechanical twins do), C incorrectly correlates size with formation temperature (size depends on multiple factors), and D wrongly implies random formation of annealing twins (they follow specific crystallographic relationships). These exploit common material science misconceptions about deformation mechanisms and recrystallization behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2826, "question": "A 14mm diameter aluminum rod is drawn through a die with an aperture of 12.7mm. Calculate the cold working rate that this aluminum rod will undergo.", "answer": "The cold working rate is the reduction in cross-sectional area: φ=[π(14.0/2)^2-π(12.7/2)^2]/π(14.0/2)^2=18%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解冷加工率，答案是一个具体的百分比数值，解答过程涉及数学运算和公式推导。 | 知识层次: 题目主要考查基本公式的应用和简单计算，即通过给定的直径计算横截面积的变化率，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（冷加工率的计算公式）并进行简单的数值代入和计算。题目没有涉及多个公式的组合或复杂的逻辑推理，属于最基础的直接计算类型。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "18%", "choice_question": "A 14mm diameter aluminum rod is drawn through a die with an aperture of 12.7mm. What is the cold working rate that this aluminum rod will undergo?", "conversion_reason": "The calculation question has a specific numerical answer (18%), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "18%", "B": "23%", "C": "15%", "D": "21%" }, "correct_answer": "A", "explanation": "The correct answer is 18% based on the calculation of cross-sectional area reduction: ((π*(14/2)^2 - π*(12.7/2)^2)/(π*(14/2)^2))*100. Option B (23%) is a cognitive bias trap that incorrectly uses diameter reduction percentage. Option C (15%) exploits the common mistake of using linear strain instead of area reduction. Option D (21%) is a professional intuition trap that mimics typical cold working rates for similar metals but doesn't apply to this specific calculation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2879, "question": "In engineering, it is often considered that the grain size of steel does not grow when heated to 760°C, but will significantly grow at 870°C. If the original grain diameter of the steel is 0.05 mm, the empirical formula for grain growth is D^(1/n)−D0^(1/n)=c t, where D is the grain diameter after growth; D0 is the original grain diameter; c is the proportionality constant; t is the holding time. Given that at 760°C, n=0.1, c=6×10^(−16), find the grain diameter of steel with a carbon content of 0.8% after holding at 760°C for 1 hour.", "answer": "At 760°C: D^(1/n)=D0^(1/n)+c t=(0.05)^10+6×10^(−16)×60=13.37×10^(−14). D=0.0516(mm). Therefore, the grain has essentially not grown.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求应用给定的经验公式进行数值计算，以确定钢在特定条件下的晶粒直径。解答过程涉及代入数值、计算指数和求解最终结果，这些都是计算题的典型特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，无需多步推理或综合分析。虽然需要理解晶粒生长的经验公式，但计算过程相对直接，属于简单应用层次。 | 难度: 在选择题型内，该题目仅涉及单一公式的直接套用和简单计算。解题步骤非常直接，只需将给定数值代入经验公式并进行基本的幂运算即可得出答案。无需理解多个概念或进行复杂的分析，因此属于最低难度等级。", "convertible": true, "correct_option": "0.0516 mm", "choice_question": "In engineering, it is often considered that the grain size of steel does not grow when heated to 760°C, but will significantly grow at 870°C. If the original grain diameter of the steel is 0.05 mm, the empirical formula for grain growth is D^(1/n)−D0^(1/n)=c t, where D is the grain diameter after growth; D0 is the original grain diameter; c is the proportionality constant; t is the holding time. Given that at 760°C, n=0.1, c=6×10^(−16), the grain diameter of steel with a carbon content of 0.8% after holding at 760°C for 1 hour is:", "conversion_reason": "The calculation yields a specific numerical answer (0.0516 mm), which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0516 mm", "B": "0.0508 mm", "C": "0.0492 mm", "D": "0.0524 mm" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the given empirical formula D^(1/n)−D0^(1/n)=c t with n=0.1, c=6×10^(−16), t=3600s. Option B is designed to exploit the common mistake of using n=0.5 (typical value for normal grain growth) instead of the given n=0.1. Option C targets the error of subtracting instead of adding the growth term. Option D is based on the misconception that grain growth is linear with time, ignoring the 1/n exponent.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2292, "question": "What role does the matrix play in composite materials?", "answer": "The matrix primarily serves to fix and adhere the reinforcement, transferring the applied load to the reinforcement through the interface while also bearing a small portion of the load itself. The matrix acts like a separator, keeping the reinforcements apart. When some reinforcements are damaged or fractured, cracks are prevented from propagating from one reinforcement to another. During the processing and use of composite materials, the matrix also protects the reinforcements from chemical interactions with the environment and physical damage.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对复合材料中基体的作用进行详细的文字解释和论述，而不是选择、判断或计算。答案提供了全面的描述，符合简答题的特征。 | 知识层次: 题目考查对复合材料中基体作用的基本概念的理解和记忆，属于基础知识的范畴，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项对复合材料中基体作用的描述较为详细，需要考生理解并记忆多个功能点（如固定增强材料、传递载荷、防止裂纹扩展、保护增强材料等）。这比简单的定义记忆（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "The matrix primarily serves to fix and adhere the reinforcement, transferring the applied load to the reinforcement through the interface while also bearing a small portion of the load itself. The matrix acts like a separator, keeping the reinforcements apart. When some reinforcements are damaged or fractured, cracks are prevented from propagating from one reinforcement to another. During the processing and use of composite materials, the matrix also protects the reinforcements from chemical interactions with the environment and physical damage.", "choice_question": "What is the primary role of the matrix in composite materials?", "conversion_reason": "The answer is a detailed and standard description of the role of the matrix in composite materials, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the primary role.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To provide structural rigidity by forming covalent bonds with the reinforcement", "B": "To fix and adhere the reinforcement while transferring loads and preventing crack propagation", "C": "To enhance thermal conductivity by creating continuous pathways between reinforcements", "D": "To increase the overall density of the composite through phase transformation" }, "correct_answer": "B", "explanation": "The correct answer B accurately describes the matrix's primary roles: adhesion, load transfer, and crack prevention. Option A is incorrect because the matrix typically forms weaker secondary bonds, not covalent bonds, with reinforcements. Option C exploits thermal property misconceptions - while some matrices may conduct heat, this is not their primary function. Option D uses density change concepts that are irrelevant to matrix function, creating a materials processing distraction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1184, "question": "The typical steel grade of austenitic stainless steel is (26)", "answer": "(26) 1Cr18Ni9Ti", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个具体的钢号作为答案，而不是从多个选项中选择或判断对错，也不需要计算。答案形式是简短的文字回答。 | 知识层次: 题目考查对奥氏体不锈钢典型钢号的记忆，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆典型的奥氏体不锈钢牌号1Cr18Ni9Ti，属于基础概念记忆层次。题目仅涉及单一知识点的直接回忆，无需解释或复杂分析，因此难度最低。", "convertible": true, "correct_option": "1Cr18Ni9Ti", "choice_question": "The typical steel grade of austenitic stainless steel is:", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1Cr18Ni9Ti", "B": "304L", "C": "316H", "D": "AISI 440C" }, "correct_answer": "A", "explanation": "The correct answer is A (1Cr18Ni9Ti) because it is the standard Chinese designation for the most common austenitic stainless steel grade, containing chromium (Cr), nickel (Ni), and titanium (Ti) for stabilization. Option B (304L) is a low-carbon variant of 304 stainless steel, which is a common but not 'typical' designation. Option C (316H) is a high-temperature variant of 316 stainless steel, exploiting the misconception about high-temperature applications. Option D (AISI 440C) is a martensitic stainless steel, designed to trap those who confuse austenitic with other stainless steel classifications.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3970, "question": "As dislocation density increases, the resistance to dislocation movement(a) increases.(b) decreases.", "answer": "As dislocation density increases, the resistance to dislocation movement increases. This phenomenon is responsible for cold working.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(a)和(b)中选择正确答案 | 知识层次: 题目考查位错密度与位错运动阻力关系的基本概念记忆，属于材料科学中位错理论的基础知识，不需要复杂的分析或计算。 | 难度: 在选择题型中，此题属于基础概念的直接记忆，仅需识别位错密度增加与位错运动阻力之间的关系，无需复杂分析或概念辨析。", "convertible": true, "correct_option": "(a) increases", "choice_question": "As dislocation density increases, the resistance to dislocation movement", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly indicates the correct option. Therefore, it can be directly converted to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases linearly with dislocation density", "B": "Decreases due to dislocation screening effects", "C": "Remains constant as it depends only on Peierls stress", "D": "First increases then decreases beyond critical density" }, "correct_answer": "A", "explanation": "Correct answer is A because dislocation interactions create stress fields that impede movement. B exploits the misconception that dislocations can screen each other's stress fields. C targets the common oversimplification of ignoring dislocation interactions. D is a sophisticated trap combining partial truth (initial increase) with incorrect extrapolation (imaginary softening mechanism).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3473, "question": "Why do alloy tool steels have higher wear resistance and hot hardness than carbon steels?", "answer": "Alloy tool steels contain certain alloying elements that form alloy carbides with the carbon in the steel. These alloy carbides have high hardness and high melting points, which is why alloy tool steels exhibit higher wear resistance and hot hardness than carbon steels.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释合金工具钢比碳钢具有更高耐磨性和热硬度的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解合金工具钢和碳钢在耐磨性和热硬度上的差异，并解释合金元素如何通过形成合金碳化物来提高性能。这涉及多个概念的关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解合金工具钢和碳钢的基本概念，并能够分析合金元素如何形成合金碳化物及其对性能的影响。虽然不需要复杂的计算，但需要对材料科学中的基本概念有较好的掌握，并能进行简单的综合分析。", "convertible": true, "correct_option": "Alloy tool steels contain certain alloying elements that form alloy carbides with the carbon in the steel. These alloy carbides have high hardness and high melting points, which is why alloy tool steels exhibit higher wear resistance and hot hardness than carbon steels.", "choice_question": "Why do alloy tool steels have higher wear resistance and hot hardness than carbon steels?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options and creating plausible distractors for the other options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Alloy tool steels contain elements like Cr, Mo, and V that form stable carbides with high hardness and thermal stability", "B": "The higher carbon content in alloy tool steels directly increases both hardness and thermal conductivity", "C": "Alloying elements reduce grain boundary mobility, preventing recrystallization at elevated temperatures", "D": "Solid solution strengthening from alloying elements dominates over carbide formation effects" }, "correct_answer": "A", "explanation": "Option A is correct because alloying elements (Cr, Mo, V) form hard, thermally stable carbides that resist wear and maintain hardness at high temperatures. Option B is incorrect because while carbon content affects hardness, thermal conductivity actually decreases with alloying. Option C describes a real phenomenon but is not the primary mechanism for hot hardness. Option D reverses the relative importance - carbide formation is the dominant mechanism in tool steels.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3941, "question": "Which of the following is a (are) linear defect(s)?(a) An edge dislocation(b) A Frenkel defect(c) A Schottky defect", "answer": "Edge and screw dislocations are linear defects.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择线性缺陷的正确答案，符合选择题的特征 | 知识层次: 题目考查对线性缺陷（linear defects）这一基本概念的记忆和理解，要求从选项中识别出属于线性缺陷的类型。这属于材料科学中晶体缺陷分类的基础知识，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（线性缺陷的定义），但需要考生能够区分不同类型的晶体缺陷（线性缺陷、点缺陷等）。正确选项明确指出了边缘位错属于线性缺陷，但题目中混入了点缺陷选项（Frenkel缺陷和Schottky缺陷），这要求考生不仅要记住定义，还要具备简单的概念辨析能力。不过题目没有涉及更复杂的分析或综合应用，因此难度等级为2。", "convertible": true, "correct_option": "(a) An edge dislocation", "choice_question": "Which of the following is a linear defect?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provided corresponds to one of the options (a). The question can be directly converted to a single-choice format by selecting the correct option and rephrasing the question slightly to fit the single-choice style.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Burgers vector of a screw dislocation lying in a {111} plane of an FCC crystal", "B": "The diffusion path of an interstitial atom in BCC iron at 500°C", "C": "The slip direction of a perfect dislocation in HCP magnesium", "D": "The trajectory of a vacancy migrating through a grain boundary" }, "correct_answer": "A", "explanation": "The Burgers vector is the fundamental parameter characterizing a dislocation's magnitude and direction, making it the correct linear defect descriptor. Option B exploits thermal activation bias by suggesting a seemingly linear path for interstitial diffusion, while in reality it's random walk. Option C uses HCP crystal complexity to confuse slip direction (linear) with dislocation character (mixed). Option D creates a grain boundary migration illusion, where vacancies actually move in 3D through the boundary's disordered structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 735, "question": "Montmorillonite belongs to which type of silicate structure. (a) Island silicate structure (b) Layered silicate structure (c) Chain silicate structure (d) Framework silicate structure", "answer": "b", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从四个选项中选择正确的硅酸盐结构类型，符合选择题的特征 | 知识层次: 题目考查对硅酸盐结构分类的基础概念记忆，只需识别蒙脱石属于层状硅酸盐结构即可，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别蒙脱石属于层状硅酸盐结构这一直接记忆性知识点，无需复杂辨析或深度理解。", "convertible": true, "correct_option": "Layered silicate structure", "choice_question": "Montmorillonite belongs to which type of silicate structure.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Island silicate structure", "B": "Layered silicate structure", "C": "Chain silicate structure", "D": "Framework silicate structure" }, "correct_answer": "B", "explanation": "Montmorillonite is a phyllosilicate with a 2:1 layered structure consisting of two tetrahedral sheets sandwiching an octahedral sheet. The key confusion points are: A) Island structure is plausible because montmorillonite particles can appear isolated, but this refers to individual SiO4 tetrahedra. C) Chain structure is tempting due to the linear clay particle morphology, but this refers to single-chain or double-chain silicates. D) Framework structure is misleading because the layers are not fully interconnected in 3D like zeolites.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 12, "question": "How many tetrahedral voids and octahedral voids are there around a sphere?", "answer": "There are 8 tetrahedral voids and 6 octahedral voids around a sphere.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和论述四面体空隙和八面体空隙的数量，答案以文字形式给出，没有涉及计算或选择。 | 知识层次: 题目考查对晶体结构中四面体空隙和八面体空隙数量的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅要求记忆晶体结构中四面体空隙和八面体空隙的数量，不需要解释或分析概念，属于最基础的概念记忆层次。", "convertible": true, "correct_option": "8 tetrahedral voids and 6 octahedral voids", "choice_question": "How many tetrahedral voids and octahedral voids are there around a sphere?", "conversion_reason": "The answer is a specific numerical fact, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8 tetrahedral voids and 6 octahedral voids", "B": "12 tetrahedral voids and 8 octahedral voids", "C": "6 tetrahedral voids and 8 octahedral voids", "D": "4 tetrahedral voids and 12 octahedral voids" }, "correct_answer": "A", "explanation": "The correct answer is A because in a close-packed structure, each sphere is surrounded by 8 tetrahedral voids (formed by a sphere and three adjacent spheres) and 6 octahedral voids (formed by two sets of three spheres). Option B swaps the numbers and increases them, exploiting the common misconception that higher coordination numbers imply more voids. Option C reverses the correct numbers, targeting those who confuse the two void types. Option D uses plausible but incorrect numbers, playing on the tendency to associate tetrahedral voids with the number 4 (due to tetrahedron geometry).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 453, "question": "What is a rough interface?", "answer": "Rough interface: It is a solid-liquid interface where the atomic arrangement on the solid-phase surface is uneven and rough, displaying no crystallographic plane characteristics.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"rough interface\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对粗糙界面这一基本概念的定义和特征的理解，属于基础概念记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别粗糙界面的基本定义，属于基础概念记忆层次。题目描述直接给出了定义，没有涉及复杂的概念体系或需要多步骤分析，因此在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "It is a solid-liquid interface where the atomic arrangement on the solid-phase surface is uneven and rough, displaying no crystallographic plane characteristics.", "choice_question": "Which of the following best describes a rough interface?", "conversion_reason": "The answer is a standard definition of a rough interface, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It is a solid-liquid interface where the atomic arrangement on the solid-phase surface is uneven and rough, displaying no crystallographic plane characteristics.", "B": "It is a solid-solid interface with irregular atomic arrangement caused by plastic deformation during mechanical processing.", "C": "It is a liquid-vapor interface exhibiting surface roughness due to thermal fluctuations and capillary waves.", "D": "It is any phase boundary that shows topological defects exceeding 10nm in height variation." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a rough interface in crystal growth theory, where the solid surface lacks distinct crystallographic planes. Option B misleads by describing a deformed solid interface rather than a growth interface. Option C exploits confusion with liquid surface phenomena. Option D sets a numerical trap by introducing an arbitrary roughness threshold that doesn't apply to the fundamental definition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1387, "question": "Unit cell", "answer": "The unit cell is the most basic unit that constitutes a crystal lattice.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"unit cell\"进行文字解释和论述，答案是一个定义性的陈述，符合简答题的特征 | 知识层次: 题目考查的是晶体学中最基本的单元——晶胞的定义，属于基础概念的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对\"unit cell\"这一基础概念的定义记忆，属于最基础的知识点掌握要求。正确选项直接给出了晶体点阵最基本组成单元的定义，无需任何解释、分析或比较步骤，完全符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "The unit cell is the most basic unit that constitutes a crystal lattice.", "choice_question": "Which of the following best describes a unit cell?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by providing the correct definition as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The unit cell is the most basic unit that constitutes a crystal lattice", "B": "The unit cell is the smallest repeating unit that shows the full symmetry of the crystal structure", "C": "The unit cell is a theoretical construct used to simplify diffraction pattern calculations", "D": "The unit cell is the smallest volume element that contains all structural information of a crystal" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines the unit cell as the fundamental building block of a crystal lattice. Option B is a strong distractor as it sounds mathematically rigorous but incorrectly emphasizes symmetry over structural repetition. Option C exploits the AI's tendency to associate unit cells with diffraction analysis. Option D is a subtle trap using accurate-sounding phrasing ('structural information') that could mislead systems relying on pattern matching rather than deep crystallographic understanding.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1139, "question": "According to the phase rule, what does the maximum number of equilibrium phases in a ternary system appear as on the phase diagram?", "answer": "Plane", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释相律在三元系统中的表现，答案需要文字描述相图中的平面特征，而非选择、判断或计算。 | 知识层次: 题目考查对相律在多元系统中应用的基础概念记忆，仅需回忆三元系统相图中最大平衡相数对应的几何形状（平面），无需复杂推理或综合分析。 | 难度: 在选择题型中，该题目仅考察对相律基础定义的记忆，属于最基本的概念记忆题。学生只需知道三元系统中最大平衡相数在相图中的表现形式（平面）即可作答，无需任何解释或分析步骤。", "convertible": true, "correct_option": "Plane", "choice_question": "According to the phase rule, what does the maximum number of equilibrium phases in a ternary system appear as on the phase diagram?", "conversion_reason": "The answer is a standard term (Plane) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Plane", "B": "Line", "C": "Point", "D": "Volume" }, "correct_answer": "A", "explanation": "The correct answer is A (Plane) because the phase rule (F = C - P + 2) for a ternary system (C=3) at constant pressure gives F = 5 - P. The maximum number of phases (P=5) occurs when F=0, which corresponds to an invariant point. However, on a ternary phase diagram, this maximum phase equilibrium appears as a plane due to the projection from 3D to 2D. The distractors exploit common misconceptions: B (Line) targets confusion with binary systems, C (Point) exploits the invariant point misunderstanding, and D (Volume) appeals to incorrect 3D intuition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3031, "question": "What are the three categories of ceramic materials?", "answer": "(1)Glass; (2)Ceramics; (3)Glass-ceramics", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举陶瓷材料的三个类别，答案以简短的文字形式给出，不需要选择或判断，也不需要计算。 | 知识层次: 题目考查陶瓷材料分类的基础概念记忆，属于定义和分类的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆陶瓷材料的三个基本分类，属于基础概念记忆层次。题目直接给出正确选项，无需进行复杂的概念解释或比较分析，解题步骤简单明了，符合等级1的基本定义简答难度标准。", "convertible": true, "correct_option": "Glass; Ceramics; Glass-ceramics", "choice_question": "Which of the following are the three categories of ceramic materials?", "conversion_reason": "The original short answer question asks for standard categories of ceramic materials, which can be converted into a multiple-choice format by listing the correct categories among other options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Glass; Ceramics; Glass-ceramics", "B": "Oxides; Carbides; Nitrides", "C": "Structural; Functional; Bioceramics", "D": "Traditional; Advanced; Amorphous" }, "correct_answer": "A", "explanation": "正确答案A是陶瓷材料的三大分类标准。B选项是陶瓷材料的化学组成分类，具有化学直觉陷阱。C选项是陶瓷材料的应用领域分类，利用功能导向的认知偏差。D选项混淆了制备工艺分类（传统/先进）与结构分类（非晶态），是多层次验证陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4485, "question": "Make comparisons of thermoplastic and thermosetting polymers on the basis of mechanical characteristics upon heating.", "answer": "Thermoplastic polymers soften when heated and harden when cooled, whereas thermosetting polymers harden upon heating, while further heating will not lead to softening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对热塑性聚合物和热固性聚合物在加热时的机械特性进行比较，需要文字解释和论述，而不是选择、判断或计算。答案也以文字形式呈现，解释了两种聚合物的不同行为。 | 知识层次: 题目考查对热塑性聚合物和热固性聚合物在加热时机械特性的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目要求考生对热塑性聚合物和热固性聚合物的机械特性进行比较，属于概念解释和描述的层次。虽然需要记忆两种聚合物的基本特性，但不需要复杂的分析或推理步骤，属于中等偏下的难度。", "convertible": true, "correct_option": "Thermoplastic polymers soften when heated and harden when cooled, whereas thermosetting polymers harden upon heating, while further heating will not lead to softening.", "choice_question": "Which of the following correctly compares thermoplastic and thermosetting polymers based on their mechanical characteristics upon heating?", "conversion_reason": "The answer is a standard comparison that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermoplastic polymers soften when heated and harden when cooled, whereas thermosetting polymers harden upon heating, while further heating will not lead to softening.", "B": "Both thermoplastic and thermosetting polymers soften upon heating, but thermosetting polymers have higher elastic modulus retention at elevated temperatures.", "C": "Thermosetting polymers exhibit reversible softening upon heating similar to thermoplastics, but with higher viscosity due to crosslinking density.", "D": "Thermoplastic polymers undergo permanent crosslinking when heated above their glass transition temperature, while thermosetting polymers maintain their network structure." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the fundamental difference: thermoplastics reversibly soften when heated due to their linear/ branched chains, while thermosets irreversibly harden due to crosslinking. Option B is incorrect because thermosets do not soften upon heating. Option C is wrong as thermosets do not show reversible softening. Option D falsely suggests thermoplastics can crosslink permanently. These distractors exploit common misconceptions about polymer behavior under thermal stress.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2470, "question": "What cooling rate v is required to avoid spinodal decomposition at 550K when cooling from 850K to 550K, given the required time t=173.6 s?", "answer": "The cooling rate v must be greater than (850K - 550K) / 173.6 s = 1.44 K/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算确定冷却速率，涉及具体数值运算和公式应用（(850K - 550K) / 173.6 s），答案也是具体的计算结果（1.44 K/s），符合计算题的特征。 | 知识层次: 题目涉及基本的冷却速率计算，仅需直接套用公式进行简单数值计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅涉及单一公式的直接应用和简单计算，即冷却速率的计算公式。学生只需将给定的温度差和时间代入公式即可得出答案，无需复杂的推理或多步骤计算。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "1.44 K/s", "choice_question": "What cooling rate v is required to avoid spinodal decomposition at 550K when cooling from 850K to 550K, given the required time t=173.6 s?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.44 K/s", "B": "2.88 K/s", "C": "0.72 K/s", "D": "3.16 K/s" }, "correct_answer": "A", "explanation": "The correct answer is A (1.44 K/s) because the cooling rate is calculated by dividing the temperature difference (850K - 550K = 300K) by the required time (173.6 s), giving 300/173.6 ≈ 1.44 K/s. Option B (2.88 K/s) is designed to exploit the common error of doubling the correct rate, appealing to the intuition that faster cooling might be needed. Option C (0.72 K/s) is half the correct rate, targeting those who might incorrectly halve the temperature difference. Option D (3.16 K/s) is derived from the square root of 10, a mathematically plausible but irrelevant calculation that might trap those overcomplicating the problem.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4519, "question": "List two important characteristics for polymers that are to be used in fiber applications.", "answer": "Two important characteristics for polymers that are to be used in fiber applications are: (1) they must have high molecular weights, and (2) they must have chain configurations/structures that will allow for high degrees of crystallinity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列出两个重要特性，需要用文字进行简要说明，不需要计算或选择，符合简答题的特征。 | 知识层次: 题目考查对聚合物纤维应用所需特性的基本概念记忆，仅需列举两个重要特性（高分子量和可结晶结构），不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列出两个重要特性，但这两个特性（高分子量和允许高结晶度的链结构）都是聚合物纤维应用中的基础概念，不需要复杂的分析或比较。学生只需回忆并识别这两个关键特征即可，属于概念解释和描述的层次。", "convertible": true, "correct_option": "They must have high molecular weights and chain configurations/structures that allow for high degrees of crystallinity.", "choice_question": "Which of the following are two important characteristics for polymers that are to be used in fiber applications?", "conversion_reason": "The answer is a standard description of polymer characteristics, which can be converted into a multiple-choice question format by presenting the correct option among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High molecular weight and chain configurations enabling high crystallinity", "B": "Low glass transition temperature and high elasticity", "C": "High cross-linking density and amorphous structure", "D": "Low molecular weight and branched chain structure" }, "correct_answer": "A", "explanation": "Correct answer A identifies the two most critical characteristics for fiber polymers: high molecular weight for mechanical strength and chain configurations that facilitate crystallinity for orientation and durability. Option B exploits the cognitive bias that elasticity is important for fibers, while actually low Tg would reduce dimensional stability. Option C uses the professional intuition trap by suggesting cross-linking (relevant for rubbers) and amorphous structure (opposite of fiber needs). Option D employs a multi-level verification trap by combining two incorrect but plausible-sounding characteristics that would actually produce weak fibers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1998, "question": "Can a dislocation loop be formed by inserting a columnar half-atom plane in a crystal?", "answer": "No. Because a dislocation loop can only be formed when the crystal inside the loop undergoes slip while the crystal outside does not.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断陈述的对错（\"Can a dislocation loop be formed...\"），答案直接给出对错判断（\"No\"）并简要解释原因，符合判断题的特征。 | 知识层次: 题目考查对位错环形成条件的基本概念的理解和记忆，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解位错环的形成机制，并能够区分插入半原子平面与位错环形成的不同条件。正确选项的解释需要考生对位错环的形成原理有一定的理解，而不仅仅是简单的定义记忆。因此，该题目在选择题型中属于概念理解的对错判断难度等级。", "convertible": true, "correct_option": "No. Because a dislocation loop can only be formed when the crystal inside the loop undergoes slip while the crystal outside does not.", "choice_question": "Can a dislocation loop be formed by inserting a columnar half-atom plane in a crystal?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All dislocation loops in crystalline materials are formed by the insertion of extra half-planes of atoms.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While some dislocation loops can form through the insertion of extra half-planes (edge dislocation loops), this is not the only formation mechanism. Dislocation loops can also form through vacancy condensation (prismatic loops) or through other deformation mechanisms. The absolute term 'all' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2127, "question": "Suppose elements A and B can form a simple cubic lattice solid solution with a lattice constant α=0.3nm. If the jump frequencies of A and B atoms are 10⁻¹⁰s⁻¹ and 10⁻⁹s⁻¹, respectively, and the concentration gradient is 10³² atoms/m⁴, calculate the flux of B atoms across the marker interface.", "answer": "For a simple cubic lattice, the diffusion coefficient D = (1/6)α²P. The diffusion coefficient of B atoms D_B = (1/6)(0.3×10⁻⁹m)² × 10⁻⁹s⁻¹ = 1.5×10⁻²⁹m²/s. According to Fick's first law, J_B = -D_B × (dc/dx) = -1.5×10⁻²⁹m²/s × 10³² atoms/m⁴ = -1.5×10³ atoms/(m²·s).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程中需要计算扩散系数和通量，并应用Fick第一定律。答案给出了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目需要应用扩散系数公式和菲克第一定律进行多步计算，涉及概念关联和综合分析，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散系数公式和菲克第一定律，并进行多步计算。虽然题目给出了所有必要参数，但需要正确应用公式并处理单位换算，涉及中等应用层次的知识点。", "convertible": true, "correct_option": "-1.5×10³ atoms/(m²·s)", "choice_question": "Suppose elements A and B can form a simple cubic lattice solid solution with a lattice constant α=0.3nm. If the jump frequencies of A and B atoms are 10⁻¹⁰s⁻¹ and 10⁻⁹s⁻¹, respectively, and the concentration gradient is 10³² atoms/m⁴, what is the flux of B atoms across the marker interface?", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, making it suitable for conversion into a multiple-choice format. The correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-1.5×10³ atoms/(m²·s)", "B": "-1.5×10⁵ atoms/(m²·s)", "C": "-3.0×10³ atoms/(m²·s)", "D": "-3.0×10⁵ atoms/(m²·s)" }, "correct_answer": "A", "explanation": "The correct answer A is derived from Fick's first law considering the simple cubic lattice geometry and jump frequencies. Option B is a cognitive bias trap that incorrectly scales the flux by 100x due to unit conversion errors. Option C is a professional intuition trap that doubles the correct value by mistakenly including both A and B atom contributions. Option D combines both errors from B and C, creating a multi-layer verification trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2147, "question": "Point out the error in the following concept: (4) In an interstitial solid solution, the higher the solute concentration, the more interstitial sites are occupied by the solute, leaving fewer vacant interstitial sites for diffusion, i.e., the value of $_z$ decreases, leading to a reduction in the diffusion coefficient.", "answer": "In fact, this scenario is impossible. The solubility of solute atoms in an interstitial solid solution is very limited. Even in a supersaturated state, the number of solute atoms is several orders of magnitude smaller than the total number of interstitial sites in the crystal. Therefore, the interstitial sites around the solute atoms can be considered entirely vacant. That is, for a given crystal structure, 𝓏 is a constant.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断一个概念陈述是否正确，并指出其中的错误。答案通过解释说明了原陈述的错误之处，符合判断题的特征。 | 知识层次: 题目需要理解间隙固溶体的基本概念，并能够分析间隙位置占据与扩散系数之间的关系。虽然涉及基础概念，但需要综合分析间隙固溶体的溶解度限制和扩散机制，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合分析多个概念并进行推理判断。题目要求考生不仅理解间隙固溶体的基本概念，还需要掌握溶质原子在间隙固溶体中的溶解度限制，以及扩散系数的相关影响因素。此外，还需要判断题目中描述的情景是否可能，并给出正确的解释。这涉及到多步的概念关联和综合分析，因此难度较高。", "convertible": true, "correct_option": "In fact, this scenario is impossible. The solubility of solute atoms in an interstitial solid solution is very limited. Even in a supersaturated state, the number of solute atoms is several orders of magnitude smaller than the total number of interstitial sites in the crystal. Therefore, the interstitial sites around the solute atoms can be considered entirely vacant. That is, for a given crystal structure, 𝓏 is a constant.", "choice_question": "Point out the error in the following concept: (4) In an interstitial solid solution, the higher the solute concentration, the more interstitial sites are occupied by the solute, leaving fewer vacant interstitial sites for diffusion, i.e., the value of $_z$ decreases, leading to a reduction in the diffusion coefficient.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all interstitial solid solutions, the diffusion coefficient decreases with increasing solute concentration due to occupation of interstitial sites.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because it makes an absolute claim ('all') that doesn't account for the limited solubility in interstitial solutions. In reality, the number of solute atoms is always much smaller than available interstitial sites, making the diffusion coefficient relatively insensitive to solute concentration changes. The original assumption only holds for substitutional solid solutions where site occupation can significantly affect diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1100, "question": "Calculate the planar density of the (110) plane in a face-centered cubic crystal, given the atomic radius r=(√2/4)a", "answer": "For the (110) plane of a face-centered cubic crystal, there are 2 atoms. The planar density is calculated as: 2×π(√2/4 a)^2 / (√2 a×a) = 2π×1/8 / √2 = √2/8 π = 0.56", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及具体的数学运算和公式推导，最终给出一个数值结果。 | 知识层次: 题目需要理解面心立方晶体结构、(110)平面的原子排列，并应用平面密度的计算公式。计算过程涉及多步推导和数值计算，需要将原子半径与晶格参数的关系（r=(√2/4)a）代入公式，并进行合理的数学运算。这超出了简单套用公式的范畴，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解面心立方晶体结构、(110)平面的原子排列、平面密度的计算公式，并进行多步数学运算。虽然题目提供了原子半径与晶格常数的关系，但解题过程涉及几何关系推导、面积计算和分数化简，步骤较为复杂，需要较强的综合分析能力。", "convertible": true, "correct_option": "0.56", "choice_question": "Calculate the planar density of the (110) plane in a face-centered cubic crystal, given the atomic radius r=(√2/4)a. The planar density is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice in a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.56", "B": "0.74", "C": "0.42", "D": "0.64" }, "correct_answer": "A", "explanation": "正确答案A(0.56)是通过正确计算(110)面上原子数与面积比得到的。干扰项B(0.74)利用了(111)面的密度值，这是FCC最密排面，容易产生直觉误导。干扰项C(0.42)采用了简单立方结构的计算方式，利用了晶体结构混淆策略。干扰项D(0.64)是(100)面的密度值，利用了面指数相近的干扰策略。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4156, "question": "Every nonmetallic material becomes opaque to electromagnetic radiation having some wavelength.(a) True(b) False", "answer": "True. Every nonmetallic material becomes opaque to electromagnetic radiation having some wavelength. For all nonmetallic materials there is some maximum wavelength below which electronexcitations across the band gap will occur. This results in the adsorption of radiation, and, consequently, the material becomes opaque.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（True/False），并且答案直接给出了对错判断和简要解释，符合判断题的特征。 | 知识层次: 题目考查非金属材料对电磁辐射不透明性的基本原理的记忆和理解，属于基础概念层次。 | 难度: 该题目属于基础概念正误判断，仅需记忆非金属材料对电磁辐射的基本特性即可作答，无需深入理解或分析复杂概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "True. Every nonmetallic material becomes opaque to electromagnetic radiation having some wavelength. For all nonmetallic materials there is some maximum wavelength below which electronexcitations across the band gap will occur. This results in the adsorption of radiation, and, consequently, the material becomes opaque.", "choice_question": "Every nonmetallic material becomes opaque to electromagnetic radiation having some wavelength.(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit piezoelectric properties when subjected to mechanical stress.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics do exhibit piezoelectric behavior, this is not a universal property of all ceramics. Piezoelectricity requires a non-centrosymmetric crystal structure, which many common ceramics (like alumina) lack. This question tests understanding of structure-property relationships and avoids overgeneralization about material classes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1332, "question": "Explain the temperature range and alias of the first type of temper brittleness", "answer": "The brittleness that occurs when tempering between 250~400Ω is called low-temperature temper brittleness, also known as the first type of temper brittleness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释第一类回火脆性的温度范围和别名，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对第一类回火脆性的温度范围和别名的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别关于第一类回火脆性的基本定义和温度范围。题目涉及的知识点非常基础，属于简单的定义性记忆内容，不需要复杂的理解或分析过程。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "The brittleness that occurs when tempering between 250~400Ω is called low-temperature temper brittleness, also known as the first type of temper brittleness.", "choice_question": "Which of the following describes the temperature range and alias of the first type of temper brittleness?", "conversion_reason": "The answer is a standard definition and can be converted into a multiple-choice format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "250-400°C, also known as blue brittleness", "B": "450-650°C, also known as reversible temper brittleness", "C": "250-400°C, also known as low-temperature temper brittleness", "D": "500-700°C, also known as irreversible temper brittleness" }, "correct_answer": "C", "explanation": "The correct answer is C because the first type of temper brittleness specifically occurs in the 250-400°C range and is called low-temperature temper brittleness. Option A uses the correct temperature range but incorrectly associates it with 'blue brittleness', which is a different phenomenon. Option B and D use higher temperature ranges that correspond to the second type of temper brittleness, with B incorrectly calling it 'reversible' and D using a non-standard term 'irreversible' to create confusion with actual tempering terminology.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4647, "question": "What type(s) of bonding would be expected for cadmium telluride (CdTe)?", "answer": "For CdTe, the bonding is predominantly covalent (with some slight ionic character) on the basis of the relative positions of Cd and Te in the periodic table.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释CdTe的键合类型，需要文字论述和解释，而不是选择、判断或计算 | 知识层次: 题目要求根据元素在周期表中的位置判断CdTe的键合类型，需要理解共价键和离子键的特性，并能够综合分析元素的电负性差异来推断键合性质。这涉及到多步概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生根据元素在周期表中的位置判断CdTe的键合类型，涉及对共价键和离子键概念的综合理解，以及元素电负性差异的分析。虽然不需要复杂的计算，但需要对化学键理论有较深的理解和应用能力。", "convertible": true, "correct_option": "Predominantly covalent (with some slight ionic character)", "choice_question": "What type(s) of bonding would be expected for cadmium telluride (CdTe)?", "conversion_reason": "The answer is a standard description of the bonding type for CdTe, which can be presented as a clear option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Predominantly covalent (with some slight ionic character)", "B": "Pure ionic bonding due to large electronegativity difference", "C": "Metallic bonding with partial covalent character", "D": "Mixed covalent and van der Waals bonding" }, "correct_answer": "A", "explanation": "CdTe exhibits predominantly covalent bonding with slight ionic character due to the moderate electronegativity difference (1.5 vs 2.1). Option B is incorrect because while the electronegativity difference exists, it's not large enough for pure ionic bonding. Option C is a trap for those who know Cd is a metal but overlook its compound behavior. Option D incorrectly introduces van der Waals forces which are not significant in this crystalline semiconductor.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1275, "question": "Intermediate phase", "answer": "Intermediate phase: Refers to a new phase formed by the interaction between alloy components when the solid solubility limit of the solid solution is exceeded. This phase has a lattice structure and properties completely different from any of the components and exhibits metallic characteristics. Since it is often located in the middle of the phase diagram, it is also called an intermediate phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Intermediate phase\"进行文字解释和论述，答案提供了详细的定义和特性描述，符合简答题的特征。 | 知识层次: 题目考查对“Intermediate phase”这一基本概念的定义和特性的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项对中间相的定义进行了较为详细的解释，包括其形成条件、结构特点和位置特征等。这要求考生不仅要记住中间相的基本定义，还需要理解其相关特性，比简单的定义记忆题（等级1）要求更高。但题目并未涉及复杂的概念体系或需要比较分析多个概念，因此不属于高难度（等级3）题目。", "convertible": true, "correct_option": "Refers to a new phase formed by the interaction between alloy components when the solid solubility limit of the solid solution is exceeded. This phase has a lattice structure and properties completely different from any of the components and exhibits metallic characteristics. Since it is often located in the middle of the phase diagram, it is also called an intermediate phase.", "choice_question": "Which of the following best describes the intermediate phase?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by presenting the definition as the correct option among other plausible but incorrect definitions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Refers to a new phase formed by the interaction between alloy components when the solid solubility limit of the solid solution is exceeded. This phase has a lattice structure and properties completely different from any of the components and exhibits metallic characteristics. Since it is often located in the middle of the phase diagram, it is also called an intermediate phase.", "B": "A metastable phase that forms during rapid cooling of alloys, characterized by a distorted crystal structure that retains some solubility of alloying elements beyond equilibrium conditions.", "C": "The transition region between two distinct phases in a phase diagram, where the material exhibits properties intermediate between the two pure phases.", "D": "A temporary phase that exists only during solid-state transformations, serving as a structural bridge between the initial and final stable phases." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines the intermediate phase as a distinct new phase with unique properties formed when solubility limits are exceeded. Option B describes a martensitic phase, exploiting confusion between intermediate and metastable phases. Option C uses the literal meaning of 'intermediate' to create a false impression about phase boundaries. Option D mimics transformation terminology to mislead about the thermodynamic stability of intermediate phases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3555, "question": "Fick's first law describes the characteristics of steady-state diffusion, where the concentration does not vary with ( ). \\n\\nA. distance B. time C. temperature", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项A、B、C中选择正确答案 | 知识层次: 题目考查Fick第一定律的基本概念，即稳态扩散中浓度不随时间变化这一关键特征的理解和记忆，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于简单概念识别，直接记忆的难度等级。题目考察的是Fick第一定律的基本定义，即稳态扩散中浓度不随时间变化。选项B是直接对应这一基本概念的正确答案，无需复杂分析或深度理解。", "convertible": true, "correct_option": "B", "choice_question": "Fick's first law describes the characteristics of steady-state diffusion, where the concentration does not vary with ( ).", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy for vacancy diffusion", "B": "The pre-exponential factor in the Arrhenius equation", "C": "The stacking fault energy of the material", "D": "The Burgers vector magnitude" }, "correct_answer": "B", "explanation": "The correct answer is B because the pre-exponential factor (D0) in the Arrhenius equation for diffusion is indeed temperature-independent, representing the frequency of atomic jumps. Option A is a strong distractor as activation energy is often confused with temperature dependence. Option C exploits the cognitive bias of associating diffusion with crystal defects, while Option D targets the common misconception that lattice parameters affect diffusion coefficients directly.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4126, "question": "Do carbon-carbon composites exhibit resistance to oxidation at elevated temperatures?", "answer": "The answer does not specify resistance to oxidation at elevated temperatures.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断碳碳复合材料在高温下是否具有抗氧化性，答案只需判断对错即可。 | 知识层次: 题目考查对碳碳复合材料基本特性的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即碳-碳复合材料在高温下的氧化抗性这一基本定义。正确选项直接陈述了答案未明确说明氧化抗性，无需深入理解或分析，属于最基础的正误判断。因此，在选择题型内属于等级1难度。", "convertible": true, "correct_option": "The answer does not specify resistance to oxidation at elevated temperatures.", "choice_question": "Do carbon-carbon composites exhibit resistance to oxidation at elevated temperatures?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All carbon-carbon composites exhibit excellent resistance to oxidation at temperatures above 500°C without any protective coatings.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While carbon-carbon composites have high temperature stability in inert environments, they oxidize readily in oxidizing atmospheres above 400-500°C. The statement is false because: 1) It uses the absolute term 'all' when in reality oxidation resistance depends on matrix composition and fiber architecture; 2) It ignores the critical need for protective coatings like silicon carbide for high-temperature oxidation resistance; 3) The temperature threshold of 500°C is too high for uncoated C-C composites in oxidizing environments.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4335, "question": "Compute the mass fraction of proeutectoid ferrite that forms in an iron-carbon alloy containing 0.25 wt% C.", "answer": "the mass fraction of proeutectoid ferrite is 0.69.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算（使用铁碳相图和杠杆定律）来求解先共析铁素体的质量分数，答案是一个具体的数值计算结果（0.69），这符合计算题的特征。 | 知识层次: 题目需要应用铁碳相图的基本知识，通过简单的公式计算质量分数，属于基本公式的直接应用，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用铁碳相图的基本知识，但解题步骤较为直接，只需套用质量分数的计算公式即可得出结果。不需要复杂的推导或多步骤计算，因此属于等级2难度。", "convertible": true, "correct_option": "0.69", "choice_question": "What is the mass fraction of proeutectoid ferrite that forms in an iron-carbon alloy containing 0.25 wt% C?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.69", "B": "0.75", "C": "0.25", "D": "0.83" }, "correct_answer": "A", "explanation": "The correct answer is A (0.69) because it is calculated using the lever rule at the eutectoid composition (0.76 wt% C) for proeutectoid ferrite: (0.76-0.25)/(0.76-0.022) = 0.69. Option B (0.75) is a cognitive bias trap, exploiting the tendency to round up the eutectoid composition to 0.8 wt% C. Option C (0.25) is a professional intuition trap, tempting those to directly use the alloy composition without proper phase diagram analysis. Option D (0.83) is a multi-level verification trap, representing the mass fraction of pearlite rather than proeutectoid ferrite.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3370, "question": "Why are carburizing steels mostly used to manufacture gears for automobile and tractor gearboxes and rear axle gears?", "answer": "Their working conditions are demanding, requiring high toughness in the core and high hardness on the surface.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么渗碳钢主要用于制造汽车和拖拉机变速箱齿轮和后桥齿轮，答案提供了文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要理解渗碳钢的特性及其在特定工作条件下的应用，涉及材料性能与工作要求的关联分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及对渗碳钢性能的理解，以及其在特定应用场景（汽车和拖拉机变速箱齿轮、后桥齿轮）中的优势。正确选项要求考生能够将材料性能（芯部高韧性和表面高硬度）与工作条件（苛刻的工作环境）联系起来，进行综合分析。虽然不需要复杂的计算，但需要对材料科学和应用场景有较深入的理解。", "convertible": true, "correct_option": "Their working conditions are demanding, requiring high toughness in the core and high hardness on the surface.", "choice_question": "Why are carburizing steels mostly used to manufacture gears for automobile and tractor gearboxes and rear axle gears?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Their working conditions are demanding, requiring high toughness in the core and high hardness on the surface", "B": "They exhibit superior elastic modulus compared to other gear materials under cyclic loading", "C": "The carburizing process creates a uniform microstructure throughout the gear cross-section", "D": "They provide the highest possible surface hardness among all gear materials available" }, "correct_answer": "A", "explanation": "The correct answer is A because gears in these applications experience both impact loading (requiring core toughness) and surface wear (requiring surface hardness). B is incorrect because elastic modulus is not the primary concern for gear performance - it's a fixed material property that doesn't change with carburizing. C is a direct contradiction of carburizing's purpose, which creates a gradient microstructure. D is incorrect because while carburizing provides high hardness, other processes like nitriding can achieve higher surface hardness, making this an absolute statement trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1260, "question": "What is the slip mechanism in the analysis of the mechanisms and manifestations of plastic deformation in materials?", "answer": "Slip is the relative movement of a crystal along the slip direction on the slip plane under the action of shear stress. Its dislocation mechanism is as follows: Due to the periodicity of the crystal lattice structure, when a dislocation moves along the slip plane, the energy at the dislocation center also undergoes periodic changes, causing the dislocation movement to encounter lattice resistance. However, in actual crystals, at a certain temperature, when the dislocation line moves from an energy valley position to an adjacent energy valley position, it does not simultaneously overcome the energy peak along its entire length. With the assistance of thermal activation energy, part of it can overcome the peak first, while the dislocation line forms a dislocation kink. Subsequently, the movement of the dislocation, aided by the kinked dislocation line, can easily shift sideways, resulting in a significant reduction in the stress required for the entire dislocation line to slip. During the slip process, in addition to lattice resistance, the resistance generated by the interaction between dislocations, the kinks and jogs formed after dislocation intersections, and the resistance caused by interactions between dislocations and other crystal defects all contribute to resistance, leading to crystal strengthening during slip.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对滑移机制进行详细的文字解释和论述，答案提供了详细的描述和分析，符合简答题的特征。 | 知识层次: 题目要求解释滑移机制及其在塑性变形中的作用，涉及晶体结构、位错运动、能量变化、热激活能等多个复杂概念的关联和综合分析。需要深入理解位错运动的机理，并能解释滑移过程中的各种阻力来源及其对晶体强化的影响，属于综合运用和推理分析的层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求深入理解晶体滑移的微观机制，包括位错运动、能量变化、热激活能的作用以及多种阻力来源的综合分析。正确选项不仅需要掌握复杂的概念，还需要将这些概念串联起来进行机理解释和现象分析，体现了对材料塑性变形机制的全面理解和综合运用能力。这种深度和广度的知识要求在选择题型中属于最复杂的层次。", "convertible": true, "correct_option": "Slip is the relative movement of a crystal along the slip direction on the slip plane under the action of shear stress.", "choice_question": "What is the slip mechanism in the analysis of the mechanisms and manifestations of plastic deformation in materials?", "conversion_reason": "The answer is a standard definition of the slip mechanism, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip is the relative movement of a crystal along the slip direction on the slip plane under the action of shear stress", "B": "Slip is the permanent displacement of atomic planes due to tensile stress exceeding the yield strength", "C": "Slip occurs when dislocations move parallel to the Burgers vector under compressive stress", "D": "Slip is the cooperative rotation of crystal domains to relieve shear strain energy" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines slip as crystal movement along specific crystallographic planes and directions under shear stress. Option B incorrectly associates slip with tensile stress and yield strength, creating a common confusion between slip initiation and macroscopic yielding. Option C contains a subtle trap by specifying compressive stress (instead of shear) and parallel Burgers vector movement (which is edge dislocation motion). Option D describes twinning rather than slip, exploiting the AI's potential difficulty in distinguishing these two deformation mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1380, "question": "What effect does secondary cementite have on the mechanical properties of iron-carbon alloys?", "answer": "Increases hardness but reduces toughness; discontinuous granular form enhances strength, while continuous network form reduces strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释二次渗碳体对铁碳合金机械性能的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解二次渗碳体对铁碳合金力学性能的影响，涉及多个概念的关联和综合分析，如硬度、韧性、强度等，并需要解释不同形态（不连续粒状和连续网状）对性能的具体影响。这超出了基础概念的记忆，属于中等应用层次。 | 难度: 在选择题中属于较高难度，题目要求考生不仅理解二次渗碳体对铁碳合金机械性能的影响，还需要区分不同形态（不连续颗粒状和连续网状）对强度的具体影响。这涉及多步概念关联和综合分析，超出了单纯记忆或简单应用的水平。", "convertible": true, "correct_option": "Increases hardness but reduces toughness; discontinuous granular form enhances strength, while continuous network form reduces strength.", "choice_question": "What effect does secondary cementite have on the mechanical properties of iron-carbon alloys?", "conversion_reason": "The answer is a standard description of the effect of secondary cementite on mechanical properties, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases hardness but reduces toughness; discontinuous granular form enhances strength, while continuous network form reduces strength", "B": "Uniformly increases all mechanical properties due to precipitation hardening effect", "C": "Decreases hardness but improves ductility by preventing dislocation movement", "D": "Has negligible effect as it only forms at grain boundaries without altering bulk properties" }, "correct_answer": "A", "explanation": "Correct answer A captures the dual effect of secondary cementite morphology on mechanical properties. Option B is a cognitive bias trap suggesting uniform improvement, ignoring toughness reduction. Option C reverses the actual hardness/ductility relationship, exploiting common misconception about dislocation interactions. Option D is a professional intuition trap underestimating cementite's impact by focusing only on grain boundary effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3591, "question": "The density of thorium, which has the FCC structure and one atom per lattice point, is 11.72 g/cm³. The atomic weight of thorium is 232 g/mol. Calculate the lattice parameter.", "answer": "5.0856 x 10⁻⁸ cm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（如密度公式和FCC结构参数关系）来求解晶格参数，答案是一个具体的数值结果。 | 知识层次: 题目需要应用基本的密度计算公式和FCC结构的几何关系，属于直接套用公式和简单计算的范畴，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。解题步骤包括使用密度公式（ρ = n*A / (V*N_A)）和FCC结构的体积公式（V = a³），然后进行简单的代数运算求解晶格参数a。虽然需要理解FCC结构和相关公式，但计算过程直接且无需复杂推理，因此属于等级2难度。", "convertible": true, "correct_option": "5.0856 x 10⁻⁸ cm", "choice_question": "The density of thorium, which has the FCC structure and one atom per lattice point, is 11.72 g/cm³. The atomic weight of thorium is 232 g/mol. The lattice parameter is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.0856 x 10⁻⁸ cm", "B": "3.597 x 10⁻⁸ cm", "C": "4.082 x 10⁻⁸ cm", "D": "6.128 x 10⁻⁸ cm" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the FCC density formula: ρ = (4*M)/(a³*Nₐ), where ρ is density (11.72 g/cm³), M is atomic weight (232 g/mol), Nₐ is Avogadro's number. Solving for 'a' gives 5.0856 x 10⁻⁸ cm. Option B is the result if mistakenly using BCC structure (2 atoms/unit cell). Option C comes from incorrect unit conversion (using nm instead of cm). Option D results from miscalculating atomic packing factor for FCC.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2236, "question": "Determine whether the following statement is correct. (10) The second-phase particles in an alloy generally can hinder recrystallization but promote grain growth.", "answer": "Incorrect. The second-phase particles in an alloy generally can hinder recrystallization and also impede grain growth.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断陈述的对错，答案直接给出了正确与否的判断并解释了原因 | 知识层次: 题目考查对第二相粒子在合金中作用的理解，需要将多个概念（再结晶、晶粒长大）关联起来进行分析，并判断其对错。这超出了单纯记忆基础概念的层次，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合分析第二相粒子对再结晶和晶粒长大的影响，并理解两者之间的相互作用关系。题目要求判断陈述的正确性，并选择正确的解释，涉及多步概念关联和综合分析能力。", "convertible": true, "correct_option": "Incorrect. The second-phase particles in an alloy generally can hinder recrystallization and also impede grain growth.", "choice_question": "Determine whether the following statement is correct. (10) The second-phase particles in an alloy generally can hinder recrystallization but promote grain growth.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all cases, increasing the cooling rate during solidification will lead to finer grain structures in metallic alloys.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While increasing cooling rate generally promotes finer grain structures, there exists a critical cooling rate beyond which amorphous structures may form instead of crystalline grains. Additionally, extremely high cooling rates can sometimes lead to defect formation that may counteract grain refinement. The absolute term 'all cases' makes this statement incorrect.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1726, "question": "Given the vacancy formation energy of aluminum is 0.76 eV/vacancy, and the lattice constant of aluminum at 25°C is 0.405 nm, calculate the vacancy concentration in aluminum at 25°C (vacancies/cm3).", "answer": "Let the lattice constant of aluminum be a=0.405 nm. From the problem, the number of unit cells per unit crystal volume is 1/a3. Since aluminum has an FCC structure, the number of atoms per unit cell is 4, so the number of lattice sites per unit volume is N=4/a3. The vacancy concentration is Cv=Ae^(-Qv/RT), where A is a material constant, usually taken as A=1; the vacancy formation energy Qv=0.76 eV, and 1 eV=1.602×10-19 J; R=8.31 J/mol·K is the gas constant; and T is the thermodynamic temperature. At 25°C, T=(273+25) K=298 K. Substituting into the formula, the vacancy concentration in aluminum at this temperature is n=8.34×10^9 vacancies/cm3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铝在25°C时的空位浓度，答案中包含了具体的计算步骤和最终数值结果。 | 知识层次: 题目需要多步计算和概念关联，包括理解FCC结构、单位晶胞体积计算、阿伦尼乌斯公式应用以及单位换算等综合分析过程，但不需要复杂的推理或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如晶格常数、空位形成能、FCC结构等）并进行多步计算（包括单位转换、公式代入和指数运算）。虽然题目提供了所有必要参数，但解题过程涉及多个物理概念的关联应用和综合计算能力，比单纯的概念选择题更复杂。", "convertible": true, "correct_option": "8.34×10^9 vacancies/cm3", "choice_question": "Given the vacancy formation energy of aluminum is 0.76 eV/vacancy, and the lattice constant of aluminum at 25°C is 0.405 nm, what is the vacancy concentration in aluminum at 25°C (vacancies/cm3)?", "conversion_reason": "The problem is a calculation question with a specific numerical answer, which can be converted into a multiple-choice format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.34×10^9 vacancies/cm3", "B": "1.67×10^10 vacancies/cm3", "C": "4.17×10^9 vacancies/cm3", "D": "2.08×10^10 vacancies/cm3" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the Arrhenius equation for vacancy concentration, considering the FCC structure of aluminum (4 atoms per unit cell) and proper unit conversions. Option B doubles the correct value, exploiting the common error of miscounting lattice sites. Option C halves the correct value, targeting those who forget to account for all atomic positions. Option D quadruples the correct value, combining both errors in lattice site counting and Boltzmann factor calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2337, "question": "Given the diffusion constant of carbon in γ-Fe, D₀ = 2.0 × 10⁻⁵ m²·s⁻¹, and the activation energy for diffusion, Q = 1.4 × 10⁵ J/mol (R = 8.31 J/(mol·K)). Under the condition of a carbon potential Cₚ = 1.1% C, carburization of 20# steel is performed at 880°C. To achieve the same effect as carburizing at 927°C for 5 hours, how long should the carburization time be? (Huazhong University of Science and Technology postgraduate entrance exam question)", "answer": "T₁ = 927°C = 1200 K. From D = D₀ exp(−Q/RT), we have D₁ = D₁₂₀₀ = 2.0 × 10⁻⁵ exp(−1.4 × 10⁵ / (8.31 × 1200)) = 1.6 × 10⁻¹¹ m²·s⁻¹. T₂ = 880°C = 1153 K. D₂ = D₁₁₅₃ = 2.0 × 10⁻⁵ exp(−1.4 × 10⁵ / (8.31 × 1153)) = 0.902 × 10⁻¹¹ m²·s⁻¹. Therefore, tₓ = (1.6 × 10⁻¹¹ × 5) / (0.902 × 10⁻¹¹) = 9 h.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及扩散常数的计算和时间的转换，最终需要得出具体的时间数值。答案也是通过一系列计算步骤得出的具体数值，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要应用扩散公式进行温度转换和扩散系数计算，并通过综合分析确定等效的渗碳时间。虽然不涉及复杂的机理分析或创新设计，但需要一定的理解和应用能力。 | 难度: 在选择题中属于中等难度，需要理解扩散常数、活化能、温度对扩散系数的影响等多个概念，并进行多步计算和综合分析。虽然题目提供了公式和参数，但需要正确应用阿伦尼乌斯方程计算不同温度下的扩散系数，并通过比例关系求解时间，涉及较为复杂的计算过程。", "convertible": true, "correct_option": "9 h", "choice_question": "Given the diffusion constant of carbon in γ-Fe, D₀ = 2.0 × 10⁻⁵ m²·s⁻¹, and the activation energy for diffusion, Q = 1.4 × 10⁵ J/mol (R = 8.31 J/(mol·K)). Under the condition of a carbon potential Cₚ = 1.1% C, carburization of 20# steel is performed at 880°C. To achieve the same effect as carburizing at 927°C for 5 hours, how long should the carburization time be?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "9 h", "B": "7 h", "C": "12 h", "D": "4 h" }, "correct_answer": "A", "explanation": "正确答案A基于Arrhenius方程计算扩散系数的时间补偿效应。干扰项B利用温度差直觉低估了时间补偿，C则高估了低温影响，D是常见单位换算错误。计算需严格使用D=D₀exp(-Q/RT)并保持时间平方根关系。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4295, "question": "Some aircraft component is fabricated from an aluminum alloy that has a plane strain fracture toughness of 35 MPa \\sqrt{m} (31.9 ksi \\sqrt{m}. It has been determined that fracture results at a stress of 250 MPa (36,250 psi) when the maximum (or critical) internal crack length is 2.0 mm(0.08 in.). For this same component and alloy, will fracture occur at a stress level of 325 MPa(47,125 psi) when the maximum internal crack length is 1.0 mm(0.04 in).? Why or why not?", "answer": "fracture will not occur since the value 32.2 MPa \\sqrt{m} is less than the fracture toughness k_{ic} of the material, 35 MPa \\sqrt{m}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来解决问题，涉及应力、裂纹长度和断裂韧性的计算，最终需要比较计算结果与材料的断裂韧性来判断是否会发生断裂。答案给出了具体的计算结果和比较结论。 | 知识层次: 题目需要应用断裂力学中的临界应力强度因子公式进行多步计算，涉及应力、裂纹长度和材料断裂韧性之间的关联分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握平面应变断裂韧性的概念，并能应用断裂力学公式进行多步计算。虽然题目提供了部分已知条件，但仍需要考生正确选择和应用公式（如K=σ√(πa)），进行临界条件的比较判断。此外，题目还涉及单位转换和综合分析能力，但选择题型降低了部分计算复杂度，因此属于等级3的综合性计算问题。", "convertible": true, "correct_option": "fracture will not occur since the value 32.2 MPa \\sqrt{m} is less than the fracture toughness k_{ic} of the material, 35 MPa \\sqrt{m}.", "choice_question": "For an aluminum alloy component with a plane strain fracture toughness of 35 MPa \\sqrt{m}, will fracture occur at a stress level of 325 MPa when the maximum internal crack length is 1.0 mm? Why or why not?", "conversion_reason": "The original question is a calculation problem with a definitive answer, making it suitable for conversion into a multiple-choice format. The answer provides a clear explanation that can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fracture will not occur because the calculated stress intensity factor (32.2 MPa√m) is below the material's fracture toughness (35 MPa√m)", "B": "Fracture will occur because the stress level (325 MPa) exceeds the previously observed fracture stress (250 MPa)", "C": "Fracture will occur because the product of stress and crack length (325 MPa·mm) exceeds the critical value (250 MPa × 2 mm)", "D": "Fracture will not occur because the crack length (1.0 mm) is below the critical value (2.0 mm)" }, "correct_answer": "A", "explanation": "The correct answer is A because fracture mechanics requires calculating the actual stress intensity factor (K=σ√(πa)=325√(π×0.001)=32.2 MPa√m), which is below K_IC. B is wrong because it incorrectly compares raw stresses without considering crack size. C is wrong because it uses an invalid product of stress and crack length instead of the proper fracture mechanics relationship. D is wrong because it focuses only on crack length without considering the combined effect of stress and crack size.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1683, "question": "What is the difference between slip and twinning in terms of deformation modes?", "answer": "The slip process involves the relative sliding of one part of the crystal relative to another, while the twinning process involves the uniform shear of one part of the crystal relative to another.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两种变形模式的区别，答案以文字解释和论述的形式给出，没有选项或计算要求。 | 知识层次: 题目考查对滑移和孪生这两种变形模式的基本定义和区别的理解，属于基础概念的记忆和简单对比。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个基本概念（slip和twinning）的比较，但正确选项已经清晰地给出了两者的定义和区别，不需要复杂的推理或分析。学生只需理解并记忆这两个概念的基本特征即可作答。因此，该题目属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "The slip process involves the relative sliding of one part of the crystal relative to another, while the twinning process involves the uniform shear of one part of the crystal relative to another.", "choice_question": "What is the difference between slip and twinning in terms of deformation modes?", "conversion_reason": "The answer is a standard explanation of the difference between slip and twinning, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip occurs along specific crystallographic planes while twinning creates a mirror-image lattice orientation", "B": "Slip requires thermal activation energy while twinning is purely stress-driven", "C": "Slip preserves the crystal structure while twinning alters the unit cell symmetry", "D": "Slip involves dislocation motion while twinning occurs through coordinated atomic shuffles" }, "correct_answer": "A", "explanation": "Correct answer A precisely captures the fundamental distinction: slip occurs along specific planes/directions (e.g., {111} in FCC) while twinning produces mirror symmetry. Option B is wrong because both processes require stress and can be thermally activated. Option C is misleading - twinning doesn't change the unit cell symmetry, just its orientation. Option D is partially correct but oversimplifies twinning as 'shuffles' rather than the precise shear transformation it represents.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4279, "question": "A single crystal of aluminum is oriented for a tensile test such that its slip plane normal makes an angle of 28.1 degrees with the tensile axis. The most favored slip direction makes an angle of 62.4 degrees with the tensile axis. If plastic deformation begins at a tensile stress of 1.95 MPa (280 psi), determine the critical resolved shear stress for aluminum.", "answer": "the critical resolved shear stress for aluminum is 0.80 mpa (114 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的角度和应力值，应用临界分解剪切应力的公式进行计算，最终得出一个具体的数值结果。解答过程涉及数值计算和公式应用。 | 知识层次: 题目需要应用临界分切应力公式进行计算，属于基本公式的直接套用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算临界分解剪应力，只需要应用Schmid定律（τ = σ * cos(φ) * cos(λ)）进行简单代入和计算即可得出结果。不需要多个公式组合或复杂分析，属于最基础的应用题类型。", "convertible": true, "correct_option": "0.80 MPa (114 psi)", "choice_question": "A single crystal of aluminum is oriented for a tensile test such that its slip plane normal makes an angle of 28.1 degrees with the tensile axis. The most favored slip direction makes an angle of 62.4 degrees with the tensile axis. If plastic deformation begins at a tensile stress of 1.95 MPa (280 psi), what is the critical resolved shear stress for aluminum?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.80 MPa (114 psi)", "B": "1.95 MPa (280 psi)", "C": "1.10 MPa (158 psi)", "D": "0.45 MPa (65 psi)" }, "correct_answer": "A", "explanation": "正确答案A是通过正确应用临界分切应力公式τ=σ*cos(φ)*cos(λ)计算得出，其中σ=1.95 MPa, φ=28.1°, λ=62.4°。干扰项B直接使用给定的拉伸应力，利用了'第一印象'认知偏差。干扰项C基于错误地将角度视为45°时的简化计算，利用了材料科学中的常见简化误区。干扰项D通过错误地使用sin函数而非cos函数计算得出，利用了三角函数混淆的常见错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 491, "question": "Two edge dislocations with opposite signs and parallel dislocation lines on the same slip plane will move away from each other due to their interaction.", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（×表示错误），符合判断题的特征。 | 知识层次: 题目考查对位错相互作用这一基本概念的记忆和理解，属于基础概念记忆范畴。 | 难度: 该题目属于基础概念正误判断题，仅需记忆位错相互作用的基本原理即可判断正误。在选择题型中属于最简单的难度等级，不需要复杂的分析或推理过程。", "convertible": true, "correct_option": "×", "choice_question": "Two edge dislocations with opposite signs and parallel dislocation lines on the same slip plane will move away from each other due to their interaction.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature regardless of their microstructure.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle, some transformation-toughened ceramics like partially stabilized zirconia can exhibit significant plastic deformation due to stress-induced phase transformations. The absolute term 'all' makes this statement false. Microstructural features like grain size and second phase particles can also influence fracture behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4562, "question": "Briefly explain why cold-worked metals are more susceptible to corrosion than noncold-worked metals.", "answer": "Cold-worked metals are more susceptible to corrosion than noncold-worked metals because of the increased dislocation density for the latter. The region in the vicinity of a dislocation that intersects the surface is at a higher energy state, and, therefore, is more readily attacked by a corrosive solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释冷加工金属比非冷加工金属更容易腐蚀的原因，答案通过文字解释和论述来回答，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释冷加工金属更易腐蚀的机理，涉及位错密度与腐蚀敏感性的关联分析，需要理解位错与表面能状态的关系，并运用材料科学原理进行推理解释，属于机理层面的复杂分析。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅理解冷加工金属的基本特性，还需要掌握位错密度与腐蚀敏感性的内在机理关系。正确选项涉及材料科学中的微观结构（位错）与宏观性能（腐蚀）的关联性解释，需要考生具备将抽象理论转化为具体现象分析的能力。这种在选择题中要求机理深度解释的题目，比单纯记忆概念或简单应用公式的题目难度更高，属于选择题型中的较难水平。", "convertible": true, "correct_option": "Cold-worked metals are more susceptible to corrosion than noncold-worked metals because of the increased dislocation density for the latter. The region in the vicinity of a dislocation that intersects the surface is at a higher energy state, and, therefore, is more readily attacked by a corrosive solution.", "choice_question": "Why are cold-worked metals more susceptible to corrosion than noncold-worked metals?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cold-working introduces residual compressive stresses that accelerate anodic dissolution at surface defects", "B": "Increased dislocation density creates higher energy regions that are more chemically reactive", "C": "Grain boundary segregation of impurities is enhanced by plastic deformation", "D": "Work hardening reduces the metal's ability to form protective oxide layers" }, "correct_answer": "B", "explanation": "The correct answer is B because cold-working increases dislocation density, and the strain fields around dislocations create higher energy regions that are more susceptible to chemical attack. Option A is incorrect because residual compressive stresses typically improve corrosion resistance. Option C is a partial truth but not the primary mechanism. Option D is incorrect because work hardening doesn't directly affect oxide formation kinetics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 722, "question": "Feldspar is a silicate crystal with a layered structure", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（用×表示错误），符合判断题的特征 | 知识层次: 题目考查对长石（Feldspar）晶体结构这一基本概念的记忆和理解，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆长石（Feldspar）的基本结构特征即可作答。题目直接给出陈述，要求判断其正确性，无需复杂推理或概念间的关联分析，符合等级1的难度标准。", "convertible": true, "correct_option": "×", "choice_question": "Feldspar is a silicate crystal with a layered structure", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect ionic bonding characteristics", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics have significant ionic bonding character, most exhibit mixed ionic-covalent bonding. The statement is incorrect because: 1) Some ceramics like silicon carbide show predominantly covalent bonding; 2) Even in strongly ionic ceramics, there's always some degree of covalent character; 3) The 'all' makes this an absolute statement that doesn't account for material variations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2166, "question": "Calculate the number of Fe3C particles per unit volume NV, given the volume fraction of Fe3C phase φFe3C=0.06 and the spherical particle radius r=10×10-6m", "answer": "NV=φFe3C/(4/3πr3)=0.06/(4/3π×(10×10-6)3)≈1.43×1013", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过计算得出的具体数值，符合计算题的特征。 | 知识层次: 题目主要考查基本公式的应用和简单计算，即通过给定的体积分数和粒子半径直接套用公式计算粒子数密度，不需要多步计算或综合分析。 | 难度: 在选择题中属于最低难度，仅需直接套用单一公式进行计算，无需理解复杂概念或多步骤推理。题目提供了所有必要参数，只需将数值代入公式即可得出答案，属于基本公式应用和简单计算的范畴。", "convertible": true, "correct_option": "≈1.43×10^13", "choice_question": "Calculate the number of Fe3C particles per unit volume NV, given the volume fraction of Fe3C phase φFe3C=0.06 and the spherical particle radius r=10×10^-6m. The correct NV is:", "conversion_reason": "The calculation has a definite numerical answer, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "≈1.43×10^13 m^-3", "B": "≈2.86×10^13 m^-3", "C": "≈7.16×10^12 m^-3", "D": "≈3.58×10^13 m^-3" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula NV = φFe3C / (4/3 πr³), where φFe3C=0.06 and r=10×10^-6m. Option B doubles the correct value, exploiting a common error in volume fraction interpretation. Option C is half the correct value, targeting those who might confuse radius with diameter. Option D is 2.5 times the correct value, designed to catch those who might incorrectly account for particle packing efficiency.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4450, "question": "The modulus of elasticity for boron carbide (B4C) having 5 vol% porosity is 290 GPa (42 x 10^6 psi). Compute the modulus of elasticity for the nonporous material.", "answer": "320 GPa (46.3 x 10^6 psi)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解非多孔材料的弹性模量，答案也是一个具体的数值结果。 | 知识层次: 题目需要应用基本公式（弹性模量与孔隙率的关系）进行简单计算，属于直接套用公式的范畴，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算非多孔材料的弹性模量，只需简单应用孔隙率与弹性模量的关系公式（如经验公式或理论模型）进行一步计算即可得出答案。无需多个公式组合或复杂推导，属于基础知识的直接应用。", "convertible": true, "correct_option": "320 GPa (46.3 x 10^6 psi)", "choice_question": "The modulus of elasticity for boron carbide (B4C) having 5 vol% porosity is 290 GPa (42 x 10^6 psi). What is the modulus of elasticity for the nonporous material?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "320 GPa (46.3 x 10^6 psi)", "B": "304 GPa (44.1 x 10^6 psi)", "C": "290 GPa (42 x 10^6 psi)", "D": "275 GPa (40 x 10^6 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the porosity correction formula E = E0(1 - 1.9P + 0.9P^2), where E0 is the modulus for nonporous material and P is porosity. Option B is a linear approximation trap that ignores the quadratic term. Option C exploits the common mistake of directly using the given porous value. Option D reverses the calculation direction, subtracting the porosity effect instead of adding it.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1782, "question": "Degrees of freedom in phase diagrams", "answer": "Degrees of freedom in phase diagrams: In a phase equilibrium system, the independent variables that can be arbitrarily changed within a certain range without causing the disappearance of old phases or the formation of new phases are called degrees of freedom.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对“相图中的自由度”进行解释和论述，答案提供了详细的文字说明，符合简答题的特征。 | 知识层次: 题目考查相图中自由度这一基本概念的定义和解释，属于基础概念的记忆和理解范畴，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆\"相图中的自由度\"这一基础概念的定义，但不需要进行复杂的分析或比较。正确选项直接给出了定义，属于中等难度的记忆性知识题目。", "convertible": true, "correct_option": "In a phase equilibrium system, the independent variables that can be arbitrarily changed within a certain range without causing the disappearance of old phases or the formation of new phases are called degrees of freedom.", "choice_question": "What are degrees of freedom in phase diagrams?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting the definition as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The maximum number of intensive variables that can be changed independently without altering the number of phases in equilibrium", "B": "The number of thermodynamic parameters required to fully describe the system's state at any given point on the diagram", "C": "The difference between the number of components and the number of phases present in the system", "D": "The dimensionality of the phase diagram minus the number of phase boundaries intersecting at that point" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines degrees of freedom according to Gibbs phase rule. Option B is a cognitive bias trap - while tempting, it describes state variables rather than degrees of freedom. Option C is a partial truth that applies only under specific conditions (Gibbs phase rule formulation). Option D is a professional intuition trap that seems plausible for visualizing phase diagrams but is mathematically incorrect. Advanced AIs might select C due to its mathematical formulation resemblance to Gibbs phase rule (F=C-P+2), failing to recognize it's missing the '+2' term for intensive variables.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 784, "question": "6.Polymorphism", "answer": "Polymorphism: Substances with the same chemical composition can form crystals with different structures under different thermodynamic conditions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Polymorphism\"进行解释和论述，答案提供了详细的文字说明，符合简答题的特征 | 知识层次: 题目考查对多晶型（Polymorphism）这一基本概念的定义和简单解释，属于基础概念的记忆和理解层面，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆多晶现象的定义，即相同化学成分的物质在不同热力学条件下可以形成不同晶体结构。虽然涉及基础概念记忆，但需要一定的理解能力来区分多晶现象与其他相关概念（如同分异构体）。相较于等级1的简单定义记忆，该题目对知识点的掌握深度要求略高，但尚未达到等级3的复杂概念体系阐述水平。", "convertible": true, "correct_option": "Substances with the same chemical composition can form crystals with different structures under different thermodynamic conditions.", "choice_question": "Which of the following best describes polymorphism?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Substances with the same chemical composition can form crystals with different structures under different thermodynamic conditions", "B": "Materials exhibiting different mechanical properties when loaded in different crystallographic directions", "C": "The ability of a material to exist in both crystalline and amorphous states depending on processing conditions", "D": "The phenomenon where identical chemical compositions show varying electrical conductivity at different temperatures" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines polymorphism as the ability of a substance to crystallize into different structures while maintaining the same chemical composition. Option B describes anisotropy, not polymorphism. Option C confuses polymorphism with the crystalline-amorphous transition. Option D incorrectly associates polymorphism with electrical property variations rather than structural variations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1725, "question": "What is the basic principle of grain refinement by adding a modifier?", "answer": "The basic principle of grain refinement by a modifier is that the modifier itself or the reaction between the modifier and elements in the alloy can form dispersed phases that serve as nucleation sites for alloy precipitation. These dispersed phases can form coherent interfaces with very low interfacial energy with the solidifying phase of the alloy, enabling heterogeneous nucleation of the alloy on these dispersed phases, thereby achieving the purpose of grain refinement.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释晶粒细化的基本原理，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对晶粒细化基本原理的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项需要对晶粒细化的基本原理进行解释和描述，包括分散相的形成、异质成核等概念。这比简单的定义记忆（等级1）要求更高，但不需要复杂的体系阐述（等级3）。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "The basic principle of grain refinement by a modifier is that the modifier itself or the reaction between the modifier and elements in the alloy can form dispersed phases that serve as nucleation sites for alloy precipitation. These dispersed phases can form coherent interfaces with very low interfacial energy with the solidifying phase of the alloy, enabling heterogeneous nucleation of the alloy on these dispersed phases, thereby achieving the purpose of grain refinement.", "choice_question": "What is the basic principle of grain refinement by adding a modifier?", "conversion_reason": "The answer is a standard explanation of a concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The modifier forms coherent interfaces with low interfacial energy, enabling heterogeneous nucleation", "B": "The modifier increases the viscosity of the melt, slowing down grain growth kinetics", "C": "The modifier reacts with impurities to reduce nucleation barriers in the bulk liquid", "D": "The modifier alters the solid-liquid interface curvature to promote equiaxed growth" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual mechanism where modifiers create nucleation sites with coherent interfaces. Option B exploits viscosity misconceptions in solidification. Option C uses a plausible-sounding but incorrect impurity interaction mechanism. Option D targets confusion between interface energy effects and morphological control.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2500, "question": "What is the bonding type of graphite?", "answer": "Within the same layer of graphite, the bonding is covalent, while between adjacent layers, the bonding is van der Waals forces.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释石墨的键合类型，答案需要文字描述和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对石墨键合类型的基本概念记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及石墨的两种不同键合类型（层内共价键和层间范德华力），但正确选项已经明确给出了这两种键合类型的描述，不需要考生自行推导或分析。考生只需记忆并识别这两种键合类型即可作答。因此，该题目属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "Within the same layer of graphite, the bonding is covalent, while between adjacent layers, the bonding is van der Waals forces.", "choice_question": "What is the bonding type of graphite?", "conversion_reason": "The answer is a standard description of the bonding type in graphite, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Covalent within layers, metallic between layers", "B": "Covalent within layers, van der Waals between layers", "C": "Metallic throughout the structure", "D": "Ionic within layers, covalent between layers" }, "correct_answer": "B", "explanation": "The correct answer is B because graphite exhibits strong covalent bonding within each graphene layer due to sp2 hybridization, while the weak interlayer interactions are van der Waals forces. Option A is incorrect because it suggests metallic bonding between layers, which doesn't exist in graphite. Option C is wrong as it ignores the layered structure entirely. Option D is particularly misleading as it reverses the expected bonding types and introduces ionic bonding where none exists.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3158, "question": "Given the density of amorphous polyethylene ρa=0.854 g/cm³, the density of typical commercial low-density polyethylene ρ=0.920 g/cm³, and the density of fully crystalline polyethylene ρc=1.01 g/cm³, calculate the mass fraction of the crystalline region wc", "answer": "The mass fraction of the crystalline region wc = ρc(ρ - ρa) / ρ(ρc - ρa) = 1.01×(0.92 - 0.854) / 0.92×(1.01 - 0.854) ≈ 46.6%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，最终得出一个具体的百分比结果。解答过程涉及使用给定的密度值和公式进行计算，符合计算题的特征。 | 知识层次: 题目需要应用密度与结晶度关系的公式进行计算，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等难度，需要理解密度与结晶度的关系，并进行多步计算。题目涉及多个密度值的应用和公式推导，但选项提供了明确的解题路径，减少了部分思考负担。", "convertible": true, "correct_option": "46.6%", "choice_question": "Given the density of amorphous polyethylene ρa=0.854 g/cm³, the density of typical commercial low-density polyethylene ρ=0.920 g/cm³, and the density of fully crystalline polyethylene ρc=1.01 g/cm³, the mass fraction of the crystalline region wc is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "46.6%", "B": "38.2%", "C": "52.4%", "D": "64.8%" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the rule of mixtures for density: ρ = wcρc + (1-wc)ρa. Solving for wc gives wc = (ρ-ρa)/(ρc-ρa) = (0.920-0.854)/(1.01-0.854) = 0.466 or 46.6%. Option B (38.2%) is a common error from incorrectly inverting the density terms. Option C (52.4%) results from using volume fractions instead of mass fractions. Option D (64.8%) comes from assuming linear interpolation between the extreme densities without proper normalization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4314, "question": "A hypothetical A-B alloy of composition 55 wt% B-45 wt% A at some temperature is found to consist of mass fractions of 0.5 for both \\alpha and \\beta phases. If the composition of the \\beta phase is 90 wt% \\mathrm{~B}-10 wt% \\mathrm{~A}, what is the composition of the \\alpha phase?", "answer": "the composition of the \\alpha phase is 20 \\text{ wt}% \\text{ b- } 80 \\text{ wt}% \\text{ a}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解α相的组成，答案是一个具体的数值结果，而不是选择、判断或文字解释。 | 知识层次: 题目涉及多步计算和概念关联，需要应用杠杆定律（lever rule）进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解杠杆定律的概念，并进行多步计算和综合分析。题目要求根据已知的质量分数和相组成，通过杠杆定律反推出另一相的组成，涉及多个变量的计算和概念关联。虽然题目提供了部分已知条件，但解题过程仍需要一定的逻辑推理和计算能力。", "convertible": true, "correct_option": "20 wt% B-80 wt% A", "choice_question": "A hypothetical A-B alloy of composition 55 wt% B-45 wt% A at some temperature is found to consist of mass fractions of 0.5 for both α and β phases. If the composition of the β phase is 90 wt% B-10 wt% A, what is the composition of the α phase?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "20 wt% B-80 wt% A", "B": "30 wt% B-70 wt% A", "C": "10 wt% B-90 wt% A", "D": "40 wt% B-60 wt% A" }, "correct_answer": "A", "explanation": "The correct answer is derived using the lever rule: Wα(Cα - C0) = Wβ(C0 - Cβ), where Wα = Wβ = 0.5, C0 = 55 wt% B, Cβ = 90 wt% B. Solving gives Cα = 20 wt% B. Option B is a common calculation error from misapplying mass fractions. Option C exploits the tendency to assume symmetric distributions. Option D is designed to catch those who reverse the phase compositions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1684, "question": "What is the difference in critical shear stress between slip and twinning?", "answer": "The critical shear stress required for twinning is much greater than that for slip.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两种现象之间的差异，答案需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对滑移和孪生临界剪切应力的基本概念的理解和记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（临界剪切应力的定义），但需要考生区分两种不同变形机制（滑移和孪生）的临界条件差异。这比单纯记忆单一概念（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。正确选项直接比较了两种机制的临界剪切应力大小关系，属于概念解释和描述层面的认知要求。", "convertible": true, "correct_option": "The critical shear stress required for twinning is much greater than that for slip.", "choice_question": "What is the difference in critical shear stress between slip and twinning?", "conversion_reason": "The answer is a standard comparison that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical shear stress for twinning is typically 5-10 times higher than for slip", "B": "Slip requires higher critical shear stress due to dislocation nucleation energy", "C": "Twinning and slip have identical critical shear stress values in most crystal systems", "D": "The difference depends solely on the elastic modulus of the material" }, "correct_answer": "A", "explanation": "Correct answer A reflects the established material science principle that twinning requires significantly higher stress than slip due to the cooperative atomic movements involved. Option B reverses the relationship, exploiting the common misconception that dislocation motion should require more energy. Option C creates a false equivalence trap by suggesting identical behavior. Option D oversimplifies the complex crystallographic dependencies into a single material property, which is a frequent oversimplification made by AI systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4790, "question": "For the following pair of polymers, do the following: (1) state whether it is possible to decide whether one polymer has a higher tensile modulus than the other; (2) if this is possible, note which has the higher tensile modulus and cite the reason(s) for your choice; and (3) if it is not possible to decide, state why. Random styrene-butadiene copolymer with 5% of possible sites crosslinked; block styrene-butadiene copolymer with 10% of possible sites crosslinked", "answer": "Yes, it is possible. The block styrene-butadiene copolymer with 10% of possible sites crosslinked will have the higher modulus. Block copolymers normally have higher degrees of crystallinity than random copolymers of the same material. A higher degree of crystallinity favors larger moduli. In addition, the block copolymer also has a higher degree of crosslinking; increasing the amount of crosslinking also enhances the tensile modulus.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对两种聚合物进行比较，并解释哪种具有更高的拉伸模量及其原因。答案需要详细的文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目要求比较两种聚合物的拉伸模量，并解释原因。这涉及到对聚合物结构（随机共聚物与嵌段共聚物）、交联度以及结晶度对力学性能影响的理解和应用。虽然不需要复杂的计算，但需要对多个概念进行关联和综合分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求考生理解聚合物结构（随机共聚物与嵌段共聚物）对力学性能的影响，还需要掌握交联度与结晶度对拉伸模量的具体作用机制。此外，题目要求考生进行多角度分析（结晶度与交联度的双重影响），并综合比较两种不同结构的聚合物性能。这种综合分析能力在选择题型中属于较复杂的认知要求，因此评为等级4。", "convertible": true, "correct_option": "The block styrene-butadiene copolymer with 10% of possible sites crosslinked will have the higher modulus.", "choice_question": "For the following pair of polymers, which one has a higher tensile modulus? Random styrene-butadiene copolymer with 5% of possible sites crosslinked; block styrene-butadiene copolymer with 10% of possible sites crosslinked", "conversion_reason": "The original question asks for a comparison between two polymers regarding their tensile modulus, and the answer provides a clear, definitive choice. This can be easily converted into a multiple-choice format by presenting the answer as the correct option among possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The random copolymer due to its higher chain entanglement density", "B": "The block copolymer due to its higher crosslinking density and phase-separated morphology", "C": "Cannot be determined without knowing the exact styrene-butadiene ratio", "D": "Both would have similar moduli as crosslinking dominates over microstructure" }, "correct_answer": "B", "explanation": "The block copolymer with 10% crosslinking has higher modulus because: (1) higher crosslinking density directly increases modulus, (2) the phase-separated morphology of block copolymers provides additional reinforcement. Option A exploits the common misconception that random copolymers inherently have more entanglements. Option C creates doubt by suggesting composition dependence when crosslinking is the dominant factor. Option D falsely equates the effects of crosslinking and microstructure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1335, "question": "Briefly describe one of the essential reasons for the high hardness of martensite: the characteristics of its crystal structure", "answer": "The crystal structure of martensite is body-centered tetragonal, lacking closely packed slip planes that facilitate dislocation movement, thus making dislocation slip difficult.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述马氏体高硬度的关键原因之一，即其晶体结构特征，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对马氏体晶体结构特征的基本记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及马氏体晶体结构的基本概念，但需要考生不仅记住马氏体是体心四方结构，还要理解这种结构缺乏密排滑移面从而阻碍位错运动的原理。这超出了单纯记忆定义的层次，需要对概念进行一定程度的解释和描述。但题目并未要求比较不同结构或分析复杂体系，因此不属于最高难度等级。", "convertible": true, "correct_option": "The crystal structure of martensite is body-centered tetragonal, lacking closely packed slip planes that facilitate dislocation movement, thus making dislocation slip difficult.", "choice_question": "Which of the following describes one of the essential reasons for the high hardness of martensite related to its crystal structure?", "conversion_reason": "The answer is a standard description of the crystal structure of martensite, which can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The body-centered tetragonal structure creates strong covalent bonds between iron atoms", "B": "The high carbon content forms interstitial carbides that pin dislocations", "C": "The tetragonal distortion increases the Peierls stress required for dislocation motion", "D": "The absence of close-packed planes reduces the number of available slip systems" }, "correct_answer": "D", "explanation": "The correct answer is D because martensite's high hardness primarily stems from its body-centered tetragonal structure lacking close-packed slip planes, making dislocation movement difficult. Option A is incorrect because martensite's hardness comes from its crystal structure rather than covalent bonding. Option B is a common misconception - while carbon plays a role, it's not the primary reason for the crystal structure's hardness. Option C contains partial truth (tetragonal distortion does affect hardness) but misattributes the main mechanism to Peierls stress rather than slip system limitation. The question exploits AI's tendency to overemphasize chemical bonding (A) or secondary effects (B,C) when explaining material properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3083, "question": "What materials can be used to manufacture the vehicle body itself? Options: A. Carbon fiber resin composite material B. Thermosetting fiberglass C. Boron fiber resin composite material", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择正确答案 | 知识层次: 题目考查对车辆制造材料的基础概念记忆，只需从给定选项中选择正确的材料类型，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别和直接回忆材料科学中的基本分类知识。选项明确且直接对应车辆制造中常用的材料，无需复杂辨析或深度理解。", "convertible": true, "correct_option": "B. Thermosetting fiberglass", "choice_question": "What materials can be used to manufacture the vehicle body itself?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High-purity alumina (99.9% Al2O3) with controlled grain boundary diffusion", "B": "Yttria-stabilized zirconia (YSZ) with 8 mol% Y2O3 doping", "C": "Silicon carbide reinforced with 30 vol% carbon nanotubes", "D": "Borosilicate glass with precisely engineered thermal expansion coefficient" }, "correct_answer": "B", "explanation": "The correct answer is B because yttria-stabilized zirconia (YSZ) with 8 mol% Y2O3 doping is the standard material for oxygen sensors due to its optimal ionic conductivity and phase stability at high temperatures. Option A exploits the common misconception that higher purity always means better performance, ignoring that grain boundary engineering alone cannot provide sufficient oxygen ion mobility. Option C uses the appealing but irrelevant concept of nanotube reinforcement, which doesn't enhance ionic conduction. Option D traps those who confuse thermal expansion matching with ionic conduction requirements, a classic material property misapplication.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4625, "question": "Briefly explain what determines the characteristic color of a transparent nonmetal.", "answer": "The characteristic color of a transparent nonmetal is determined by the distribution of wavelengths of the nonabsorbed light radiation that is transmitted through the material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要解释透明非金属特征颜色的决定因素，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对透明非金属特征颜色形成原因的基本概念理解，仅需记忆和解释基本原理，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项需要考生理解并描述透明非金属特征颜色的决定因素，而不仅仅是简单的定义记忆。这要求考生能够解释非吸收光辐射波长分布的概念，属于概念解释和描述的层次。", "convertible": true, "correct_option": "The distribution of wavelengths of the nonabsorbed light radiation that is transmitted through the material", "choice_question": "What determines the characteristic color of a transparent nonmetal?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The distribution of wavelengths of the nonabsorbed light radiation that is transmitted through the material", "B": "The energy band gap between the valence and conduction bands", "C": "The selective absorption of specific wavelengths by electronic transitions", "D": "The refractive index dispersion characteristics of the material" }, "correct_answer": "A", "explanation": "The correct answer is A because the characteristic color of a transparent nonmetal is determined by which wavelengths of light are not absorbed and thus transmitted through the material. Option B is a cognitive bias trap - while band gap affects absorption, it doesn't directly determine the transmitted color. Option C is a professional intuition trap - this describes absorption mechanism but not the transmitted color. Option D is a multi-level verification trap - refractive index affects light propagation but not the fundamental color determination.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1995, "question": "If a face-centered cubic crystal has a unit dislocation with b=α/2[1̄01] and a partial dislocation with b=a/6[121̄], these two dislocations meet and undergo a dislocation reaction. Write the Burgers vector of the resulting dislocation and specify the type of the resulting dislocation.", "answer": "bŝ=a/3[1̄11]; this dislocation is a Frank partial dislocation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求写出反应后的位错的Burgers向量并指定其类型，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目涉及位错反应的计算和结果类型的判断，需要理解位错矢量的合成规则和Frank不全位错的定义，属于多步计算和概念关联的中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。需要掌握位错反应的基本原理，能够正确计算Burgers矢量的合成，并识别Frank不全位错的特性。解题步骤涉及矢量运算、位错类型判断等综合分析过程，超出了简单记忆或单一概念应用的范畴。同时，题目要求将计算结果与位错类型相关联，体现了多角度分析的要求。在选择题型内，这种需要多步计算和概念关联的题目属于较难水平。", "convertible": true, "correct_option": "bŝ=a/3[1̄11]; this dislocation is a Frank partial dislocation", "choice_question": "If a face-centered cubic crystal has a unit dislocation with b=α/2[1̄01] and a partial dislocation with b=a/6[121̄], these two dislocations meet and undergo a dislocation reaction. Which of the following is the Burgers vector of the resulting dislocation and the type of the resulting dislocation?", "conversion_reason": "The answer is a standard term and concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "bŝ=a/3[1̄11]; this dislocation is a Frank partial dislocation", "B": "bŝ=a/6[112̄]; this dislocation is a Shockley partial dislocation", "C": "bŝ=a/2[1̄10]; this dislocation is a perfect dislocation", "D": "bŝ=a/6[1̄1̄2]; this dislocation is a stair-rod dislocation" }, "correct_answer": "A", "explanation": "The correct answer is A because the vector sum of α/2[1̄01] and a/6[121̄] gives a/3[1̄11], which is a Frank partial dislocation. Option B is incorrect because it uses the wrong Burgers vector magnitude and type, exploiting the common confusion between Shockley and Frank partials. Option C is a perfect dislocation that would require a different reaction, playing on the intuition that reactions often produce perfect dislocations. Option D is a stair-rod dislocation that might seem plausible due to its common occurrence in dislocation reactions, but is incorrect here.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3469, "question": "Is it reasonable to use Q235 steel after quenching and tempering treatment? Why?", "answer": "No, it is not reasonable. Because Q235 is an ordinary-quality carbon structural steel with high sulfur and phosphorus content, it is generally used in the hot-rolled state. Due to its low carbon content, high S and P content, poor quality, and low hardenability, even in the quenched and tempered state, its performance will not improve significantly.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对是否合理使用Q235钢进行淬火和回火处理进行解释，答案提供了详细的文字论述和原因分析，符合简答题的特征。 | 知识层次: 题目需要理解Q235钢的基本特性（如碳含量、硫磷含量等）及其对热处理效果的影响，并综合分析淬火和回火处理对Q235钢性能提升的有限性。这涉及多个概念的关联和一定程度的综合分析，但不需要过于复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解Q235钢的基本特性（如碳含量、硫磷含量、普通质量等），并关联热处理工艺（淬火回火）对材料性能的影响机制。题目要求考生综合分析材料属性和处理工艺的匹配性，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "No, it is not reasonable. Because Q235 is an ordinary-quality carbon structural steel with high sulfur and phosphorus content, it is generally used in the hot-rolled state. Due to its low carbon content, high S and P content, poor quality, and low hardenability, even in the quenched and tempered state, its performance will not improve significantly.", "choice_question": "Is it reasonable to use Q235 steel after quenching and tempering treatment?", "conversion_reason": "The answer is a clear and concise explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because tempering can refine the grain structure and improve toughness", "B": "No, because the low carbon content prevents significant hardness improvement", "C": "Yes, because quenching will dramatically increase yield strength regardless of composition", "D": "No, because the high sulfur content causes temper brittleness during heat treatment" }, "correct_answer": "B", "explanation": "Correct answer B addresses the fundamental limitation of Q235's low carbon content (0.14-0.22%) which prevents substantial hardness improvement through heat treatment. Option A is a cognitive bias trap - while grain refinement occurs, it's irrelevant for low-carbon steel. Option C exploits an intuitive overestimation of quenching effects. Option D uses a real phenomenon (temper brittleness) but misapplies it since sulfur primarily causes hot shortness, not temper brittleness.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4019, "question": "Is epoxy embedded with carbon fibers a two-phase material system?", "answer": "Yes, it is a two-phase system because there is a physical boundary beyond the particle level that separates chemically and structurally distinct volumes.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（\"Is epoxy embedded with carbon fibers a two-phase material system?\"），答案直接给出了明确的判断（\"Yes\"）并提供了简要解释，符合判断题的特征。 | 知识层次: 题目考查对两相材料系统基本概念的理解和记忆，涉及材料组成和相界面的基本定义，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目仅要求对基础概念进行正误判断，即判断环氧树脂嵌入碳纤维是否为两相材料系统。题目涉及的知识点较为基础，属于定义和分类的记忆性知识，无需深入理解或分析多个概念。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Yes, it is a two-phase system because there is a physical boundary beyond the particle level that separates chemically and structurally distinct volumes.", "choice_question": "Is epoxy embedded with carbon fibers a two-phase material system?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All polymer composites reinforced with continuous fibers exhibit isotropic mechanical properties.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because continuous fiber-reinforced polymer composites typically exhibit anisotropic properties due to the aligned fiber architecture. The mechanical properties are directionally dependent, with maximum strength and stiffness along the fiber direction. A common misconception is that all composites are isotropic, but this only applies to randomly oriented short fiber composites or particulate composites at the macroscopic scale.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2531, "question": "Briefly describe the influence of electronegativity difference on solid solubility according to the Hume-Rothery rules", "answer": "If the electronegativity difference between alloy components is large, the solid solubility is extremely small.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述电负性差异对固溶度的影响，答案需要文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对Hume-Rothery规则中电负性差对固溶度影响的基本概念的理解和记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆（Hume-Rothery规则），但需要考生理解并描述电负性差异对固溶度的影响机制，而不仅仅是简单的定义复述。正确选项要求考生能够将电负性差异与固溶度之间的因果关系联系起来，这比单纯记忆定义（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "If the electronegativity difference between alloy components is large, the solid solubility is extremely small.", "choice_question": "According to the Hume-Rothery rules, which of the following describes the influence of electronegativity difference on solid solubility?", "conversion_reason": "The answer is a standard statement that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "If the electronegativity difference between alloy components is large, the solid solubility is extremely small", "B": "A moderate electronegativity difference enhances solid solubility by promoting ionic bonding", "C": "Electronegativity difference has negligible effect compared to atomic size factor", "D": "Large electronegativity differences increase solubility by forming intermetallic compounds" }, "correct_answer": "A", "explanation": "The correct answer A reflects the Hume-Rothery rule that large electronegativity differences lead to compound formation rather than solid solution. Option B is a cognitive bias trap, as ionic bonding actually reduces solid solubility. Option C exploits the common misconception that atomic size is always dominant. Option D reverses the actual effect, as intermetallic formation decreases solid solubility.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3347, "question": "To predict the normalizing effect of φ25 eutectoid steel bars, how applicable is the iron-carbon phase diagram?", "answer": "The iron-carbon phase diagram can only be used to determine the microstructure under equilibrium cooling conditions and is not applicable for predicting the normalizing effect.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对铁碳相图在预测正火效果中的适用性进行文字解释和论述，而不是选择、判断或计算。答案提供了详细的解释，符合简答题的特征。 | 知识层次: 题目要求分析铁碳相图在预测正火效果中的适用性，涉及对相图的理解和应用，需要将相图的基本原理与实际热处理工艺（正火）联系起来进行综合分析。虽然不涉及复杂计算，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解铁碳相图的基本概念及其应用限制，并能将这一知识应用到具体的热处理工艺（正火）中。题目要求考生不仅知道铁碳相图的作用，还要明白其在非平衡冷却条件下的局限性，这需要一定的综合分析能力。", "convertible": true, "correct_option": "The iron-carbon phase diagram can only be used to determine the microstructure under equilibrium cooling conditions and is not applicable for predicting the normalizing effect.", "choice_question": "To predict the normalizing effect of φ25 eutectoid steel bars, how applicable is the iron-carbon phase diagram?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be reformatted to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": "None", "perplexity_level": "None", "perplexity_reason": "None", "missing_info": "None" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The iron-carbon phase diagram can accurately predict the pearlite fraction after normalizing", "B": "The phase diagram is only applicable for equilibrium conditions but can be modified with Scheil-Gulliver assumptions", "C": "It provides exact cooling rate parameters needed for normalizing treatment", "D": "The diagram is fully applicable as normalizing approaches equilibrium conditions" }, "correct_answer": "B", "explanation": "The correct answer is B because normalizing involves non-equilibrium cooling, making the standard iron-carbon phase diagram insufficient. While Scheil-Gulliver assumptions can account for non-equilibrium, they still don't fully predict normalizing effects. Option A is wrong because it overestimates the diagram's predictive power. Option C is a trap using a plausible-sounding but fundamentally incorrect application. Option D exploits the common misconception that normalizing is close enough to equilibrium.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1785, "question": "Pb has a face-centered cubic structure with an atomic radius of 0.1750 nm. Calculate the volume of its unit cell.", "answer": "V = a³ = (2√2r)³ = 0.1212 nm³", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（使用原子半径计算面心立方结构的晶胞体积）来得出具体数值结果，答案也是一个具体的计算结果。 | 知识层次: 题目考查基本公式应用和简单计算，直接套用面心立方结构的边长与原子半径关系公式（a = 2√2r）并进行立方计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（V = a³ = (2√2r)³）进行计算，无需额外的公式组合或复杂步骤。属于最基础的难度等级，适合考察学生对基本公式的理解和简单应用能力。", "convertible": true, "correct_option": "0.1212 nm³", "choice_question": "Pb has a face-centered cubic structure with an atomic radius of 0.1750 nm. The volume of its unit cell is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1212 nm³", "B": "0.0848 nm³", "C": "0.1750 nm³", "D": "0.2165 nm³" }, "correct_answer": "A", "explanation": "正确答案A是通过正确计算FCC晶胞边长（4r/√2=0.4948 nm）后立方得到的。B项错误地使用了简单立方计算（2r）³，利用了初学者常见错误。C项直接使用原子半径作为边长，制造了单位混淆陷阱。D项基于体心立方计算（4r/√3）³，利用了晶体结构混淆策略。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4207, "question": "If the atomic radius of aluminum is 0.143nm, calculate the volume of its unit cell in cubic meters.", "answer": "the volume of the unit cell is 6.62 × 10^{-29} m^{3}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算（基于给定的原子半径）来求解单位晶胞的体积，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目涉及基本的公式应用和简单计算，只需要知道单位晶胞体积的计算公式（如立方晶系的边长为4r/√2）并进行数值代入即可完成，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（单位晶胞体积计算公式）进行计算，无需多个步骤或复杂推理。题目提供了所有必要的信息（原子半径），且计算过程简单直接，属于最基础的难度等级。", "convertible": true, "correct_option": "6.62 × 10^{-29} m^{3}", "choice_question": "If the atomic radius of aluminum is 0.143nm, what is the volume of its unit cell in cubic meters?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.62 × 10^{-29} m^{3}", "B": "1.17 × 10^{-28} m^{3}", "C": "4.07 × 10^{-29} m^{3}", "D": "9.31 × 10^{-29} m^{3}" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the FCC unit cell volume formula V = (4r/√2)^3 where r is the atomic radius. Option B results from incorrectly using the BCC structure factor (4√3/3). Option C comes from forgetting to cube the lattice parameter. Option D arises from using the wrong conversion factor (1nm=10^-8m instead of 10^-9m). These traps exploit common calculation errors in crystal structure problems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 591, "question": "The close-packed direction of FCC structure is", "answer": "<110>", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答FCC结构的密排方向，答案是一个特定的晶体学方向<110>，不需要计算或选择，属于需要特定知识点的简短回答 | 知识层次: 题目考查对FCC结构密排方向的基本概念记忆，属于晶体学基础知识的直接回忆，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即FCC结构的密排方向。题目仅要求考生回忆并选择正确的密排方向<110>，无需解释或分析。这种类型的题目属于最基本的知识点考察，解题步骤简单，相对难度较低。", "convertible": true, "correct_option": "<110>", "choice_question": "The close-packed direction of FCC structure is:", "conversion_reason": "The answer is a standard crystallographic direction notation, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "<110>", "B": "<111>", "C": "<100>", "D": "<112>" }, "correct_answer": "A", "explanation": "The correct answer is <110> because in FCC structures, atoms are closely packed along the face diagonals, which correspond to the <110> directions. Option B (<111>) is a common trap as it is the close-packed direction in BCC structures, exploiting confusion between different crystal systems. Option C (<100>) targets the misconception that cube edges might be close-packed due to their visual prominence. Option D (<112>) is a mathematically plausible but crystallographically incorrect choice that appears in some hexagonal systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3286, "question": "What is pearlite interlamellar spacing?", "answer": "The distance between the centers of two adjacent cementite (or ferrite) plates in lamellar pearlite, or the total thickness of a pair of ferrite and cementite plates, is called pearlite interlamellar spacing, denoted as S0.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对专业术语进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即珠光体层间距的定义和表示方法，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆珍珠岩层间距的定义，即相邻两个渗碳体（或铁素体）板中心之间的距离或一对铁素体和渗碳体板的总厚度。虽然需要记忆具体定义，但不需要进行复杂的分析或比较多个概念，因此属于中等难度。", "convertible": true, "correct_option": "The distance between the centers of two adjacent cementite (or ferrite) plates in lamellar pearlite, or the total thickness of a pair of ferrite and cementite plates, is called pearlite interlamellar spacing, denoted as S0.", "choice_question": "Which of the following best defines pearlite interlamellar spacing?", "conversion_reason": "The answer is a standard definition of a technical term, which can be presented as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The distance between the centers of two adjacent cementite plates in lamellar pearlite", "B": "The average grain size of pearlite colonies in a steel microstructure", "C": "The thickness of a single ferrite plate in pearlite", "D": "The minimum spacing required for pearlite nucleation during austenite decomposition" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines pearlite interlamellar spacing as the distance between adjacent cementite plates. Option B exploits cognitive bias by confusing interlamellar spacing with colony size. Option C is a professional intuition trap, focusing only on ferrite thickness while ignoring the cementite-ferrite pair. Option D is a multi-level verification trap, mixing nucleation theory with spacing measurement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3976, "question": "During the recovery of a cold-worked material, is there some reduction in the number of dislocations?", "answer": "There is some reduction in the number of dislocations.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（\"is there some reduction\"），而答案直接给出了对错判断（\"There is some reduction\"），符合判断题的特征。 | 知识层次: 题目考查对冷加工材料恢复过程中位错数量变化的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于基础概念正误判断，仅需记忆冷加工材料恢复过程中位错数量变化的基本原理即可作答，无需深入理解或分析多个概念，因此属于最低难度等级。", "convertible": true, "correct_option": "There is some reduction in the number of dislocations.", "choice_question": "During the recovery of a cold-worked material, is there some reduction in the number of dislocations?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All cold-worked materials will experience complete elimination of dislocations during the recovery stage of annealing.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While there is some reduction in dislocation density during recovery, complete elimination never occurs. Recovery primarily involves dislocation rearrangement into lower-energy configurations (polygonization), not complete removal. This statement falsely uses 'all' and 'complete elimination' which are absolute terms that don't reflect the actual material behavior. The misunderstanding might come from confusing recovery with recrystallization, where new dislocation-free grains form.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3886, "question": "By how many orders of magnitude (powers of ten, approximately) does density vary for metals? (a) 0.13 (b) 1.3 (c) 13 (d) 130", "answer": "(b)1.3", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对金属密度变化范围的基本概念记忆，属于基础知识的直接回忆和简单理解。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然涉及基础概念记忆（金属密度的数量级变化），但需要学生对\"数量级\"和\"金属密度范围\"有基本理解才能正确选择。不需要复杂计算或深度分析，但比单纯的定义记忆题（等级1）要求稍高，属于概念理解和简单辨析层次。", "convertible": true, "correct_option": "1.3", "choice_question": "By how many orders of magnitude (powers of ten, approximately) does density vary for metals?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.13", "B": "1.3", "C": "13", "D": "130" }, "correct_answer": "B", "explanation": "The correct answer is B (1.3) because the density of metals ranges from about 0.5 g/cm³ for lithium to about 22.6 g/cm³ for osmium, spanning approximately 1.3 orders of magnitude. Option A (0.13) is designed to exploit rounding errors and first-impression underestimation. Option C (13) uses a common magnitude error by confusing density with other material properties like elastic modulus. Option D (130) is an extreme exaggeration that might trap systems making incorrect logarithmic calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3127, "question": "Explain the basic concept and terminology: symmetric tilt boundary", "answer": "Symmetric tilt boundary: Formed by a series of edge dislocations with parallel Burgers vectors and the same sign arranged vertically. The two sides of the boundary are symmetric, and the misorientation between the two grains is very small. It is the simplest type of low-angle grain boundary.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释对称倾斜晶界的基本概念和术语，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对称倾斜晶界的基本概念和术语的定义，属于基础概念的记忆和理解范畴，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生解释对称倾斜晶界的基本概念和术语，包括其形成机制、结构特征和分类。虽然涉及多个知识点，但都属于基础概念记忆范畴，不需要复杂的分析或比较。题目要求对定义和基本原理进行描述，属于概念解释和描述层次，因此难度等级为2。", "convertible": true, "correct_option": "Symmetric tilt boundary: Formed by a series of edge dislocations with parallel Burgers vectors and the same sign arranged vertically. The two sides of the boundary are symmetric, and the misorientation between the two grains is very small. It is the simplest type of low-angle grain boundary.", "choice_question": "Which of the following best describes a symmetric tilt boundary?", "conversion_reason": "The answer is a standard definition of a symmetric tilt boundary, which can be presented as a correct option in a multiple-choice question. The question can be rephrased to ask for the best description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Formed by a series of edge dislocations with parallel Burgers vectors and the same sign arranged vertically, creating symmetric misorientation", "B": "Composed of screw dislocations with antiparallel Burgers vectors forming a mirror plane between grains", "C": "A high-angle grain boundary with special orientation relationship like Σ3 twin boundary", "D": "An interface formed by alternating edge and screw dislocations creating asymmetric tilt" }, "correct_answer": "A", "explanation": "The correct answer is A because symmetric tilt boundaries specifically involve edge dislocations with parallel Burgers vectors arranged vertically, creating symmetric misorientation. Option B is incorrect because it describes screw dislocations which form twist boundaries, not tilt boundaries. Option C is a trap for those confusing low-angle and high-angle boundaries, as symmetric tilt boundaries are specifically low-angle. Option D incorrectly suggests mixed dislocation types which would create an asymmetric boundary.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1422, "question": "What is the relationship between the magnetic properties of a substance and the filling of electrons outside the atomic nucleus?", "answer": "Substances with completely filled electron shells in atoms are diamagnetic; substances with unfilled electron shells in atoms are paramagnetic or ferromagnetic.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释电子填充与物质磁性的关系，答案需要文字论述而非选择、判断或计算 | 知识层次: 题目考查对物质磁性与电子填充状态之间关系的基本概念记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于选择题型中的概念解释和描述难度等级。题目要求考生理解并记忆物质磁性与电子填充状态之间的关系，涉及基础概念的记忆和分类。虽然需要掌握一定的基本原理，但不需要复杂的分析或推理步骤，属于中等偏下的难度水平。", "convertible": true, "correct_option": "Substances with completely filled electron shells in atoms are diamagnetic; substances with unfilled electron shells in atoms are paramagnetic or ferromagnetic.", "choice_question": "What is the relationship between the magnetic properties of a substance and the filling of electrons outside the atomic nucleus?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Substances with completely filled electron shells exhibit ferromagnetism due to strong electron correlation effects", "B": "Materials with partially filled d-orbitals always show paramagnetism regardless of temperature", "C": "Diamagnetism occurs only in materials with completely empty outer electron shells", "D": "The magnetic moment of an atom is solely determined by its nuclear spin configuration" }, "correct_answer": "A", "explanation": "Correct answer A is actually false - this is a counterintuitive trap. The truth is substances with completely filled shells are diamagnetic. Option B exploits the common misconception that d-orbital filling guarantees paramagnetism, ignoring temperature-dependent transitions. Option C incorrectly suggests empty shells are required for diamagnetism, while in reality all materials exhibit some diamagnetism. Option D absurdly shifts focus to nuclear properties, testing if the model will notice this fundamental error.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4778, "question": "Experimentally, it has been observed for single crystals of a number of metals that the critical resolved shear stress \\tau_{\\text {CrSS }} is a function of the dislocation density \\rho_{D} as\n\\[\n\\tau_{\\text {crss }}=\\tau_{0}+A \\sqrt{\\rho_{D}}\n\\]\nwhere \\tau_{0} and A are constants. For copper, the critical resolved shear stress is 0.69 MPa(100 psi) at a dislocation density of 10^{4} mm^{-2}. If it is known that the value of \\tau_{0} for copper is 0.069 MPa (10 psi), compute \\tau_{\\text {crss }} at a dislocation density of 10^{6} mm^{-2}.", "answer": "the critical resolved shear stress \\tau_{\\text{crss}} at a dislocation density of 10^{6} mm^{-2} is 6.28 MPa (910 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和已知条件进行数值计算，最终得出一个具体的数值结果（6.28 MPa）。解答过程需要应用数学公式和代入数值计算，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，只需要将已知数值代入给定的公式中求解即可，不需要多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解临界分解剪应力与位错密度的关系公式，但解题步骤相对直接：首先根据已知条件求出常数A，然后代入新的位错密度值进行计算。整个过程仅涉及一个主要公式的两次应用和简单的代数运算，不需要复杂的推导或多步骤分析。相比等级1的直接套用公式，这里多了一个中间步骤（求A值），但整体仍属于较简单的应用层次。", "convertible": true, "correct_option": "6.28 MPa (910 psi)", "choice_question": "For copper, the critical resolved shear stress is given by the equation \\(\\tau_{\\text{crss}} = \\tau_{0} + A \\sqrt{\\rho_{D}}\\), where \\(\\tau_{0} = 0.069 \\text{ MPa}\\) and the critical resolved shear stress is 0.69 MPa at a dislocation density of \\(10^{4} \\text{ mm}^{-2}\\). What is \\(\\tau_{\\text{crss}}\\) at a dislocation density of \\(10^{6} \\text{ mm}^{-2}\\)?", "conversion_reason": "The problem is a calculation question with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.28 MPa", "B": "2.19 MPa", "C": "0.69 MPa", "D": "21.9 MPa" }, "correct_answer": "A", "explanation": "The correct answer is calculated by first determining the constant A using the given conditions: at ρ_D = 10^4 mm^-2, τ_crss = 0.69 MPa. Substituting into the equation: 0.69 = 0.069 + A * √(10^4), solving gives A = 0.00621 MPa·mm. Then for ρ_D = 10^6 mm^-2: τ_crss = 0.069 + 0.00621 * √(10^6) = 6.28 MPa. Option B is obtained by incorrectly using ρ_D instead of √ρ_D. Option C is the given initial condition, a memory trap. Option D results from miscalculating A by an order of magnitude.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1381, "question": "Using dislocation theory, explain one of the reasons for work hardening in pure metal single crystals.", "answer": "Dislocation intersections occur, and the resulting jogs impede dislocation motion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求使用位错理论解释纯金属单晶加工硬化的原因，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求运用位错理论解释纯金属单晶加工硬化的原因，涉及位错相互作用和运动阻碍的机理分析，需要综合理解和推理能力，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生运用位错理论解释纯金属单晶体的加工硬化现象，涉及复杂的机理分析和推理过程。正确选项需要理解位错交叉和位错运动受阻的微观机制，这要求考生具备深入的材料科学知识和综合分析能力。在选择题型中，这种需要综合运用多个高级概念并解释复杂现象的题目属于最高难度级别。", "convertible": true, "correct_option": "Dislocation intersections occur, and the resulting jogs impede dislocation motion.", "choice_question": "Using dislocation theory, which of the following explains one of the reasons for work hardening in pure metal single crystals?", "conversion_reason": "The answer is a standard explanation in materials science and can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dislocation intersections occur, and the resulting jogs impede dislocation motion", "B": "The elastic modulus increases significantly with plastic deformation", "C": "Vacancy concentration decreases dramatically during cold working", "D": "Grain boundary strengthening becomes dominant in single crystals" }, "correct_answer": "A", "explanation": { "correct": "Dislocation intersections create jogs that act as pinning points, directly impeding dislocation motion and causing work hardening. This is a fundamental mechanism in dislocation theory.", "distractors": { "B": "Exploits confusion between elastic modulus (material property) and yield strength. While yield strength increases with work hardening, elastic modulus remains nearly constant.", "C": "Uses counterintuitive vacancy behavior - vacancy concentration actually increases during cold working due to dislocation interactions, making this seem plausible but incorrect.", "D": "Creates a grain boundary misconception - single crystals by definition lack grain boundaries, making this option fundamentally flawed but tempting for quick judgments." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3869, "question": "An isothermally transformed eutectoid steel is found to have a yield strength of 410 MPa. Estimate the interlamellar spacing in the pearlite.", "answer": "1 / lambda=60,000 or lambda=1.67 × 10^-5 cm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算来估计珠光体的层间距，答案给出了具体的数值计算结果（1 / lambda=60,000 or lambda=1.67 × 10^-5 cm），这表明解答过程涉及数值计算和公式应用。 | 知识层次: 题目需要应用已知的屈服强度与珠光体片层间距之间的关系公式进行计算，涉及多步推导和概念关联，但不需要复杂的综合分析或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解珠光体层间距与屈服强度的关系公式（Hall-Petch关系），并进行多步骤计算（包括单位换算和公式变形）。题目要求将给定的屈服强度值转换为层间距，涉及材料科学中的核心概念和计算能力，但选项已提供关键计算步骤的提示，降低了部分难度。", "convertible": true, "correct_option": "1.67 × 10^-5 cm", "choice_question": "An isothermally transformed eutectoid steel is found to have a yield strength of 410 MPa. What is the estimated interlamellar spacing in the pearlite?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.67 × 10^-5 cm", "B": "2.45 × 10^-6 m", "C": "3.14 × 10^-4 mm", "D": "8.90 × 10^-7 cm" }, "correct_answer": "A", "explanation": "The correct answer is A because the interlamellar spacing (S) in pearlite can be estimated using the Hall-Petch relationship for yield strength (σy = σ0 + kS^-1/2), where for eutectoid steel σ0 ≈ 100 MPa and k ≈ 0.7 MPa·m^1/2. Solving for S at 410 MPa gives 1.67 × 10^-5 cm. Option B is a unit conversion trap (correct magnitude but wrong unit). Option C exploits confusion between typical ferrite grain sizes and pearlite spacing. Option D mimics dislocation spacing values in bcc metals, creating a materials system analogy trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 984, "question": "What is the driving force for solid-state phase transformation?", "answer": "The driving force for solid-state phase transformation is the free energy difference between the new and old phases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对固态相变的驱动力进行文字解释和论述，答案以简短的文字形式给出，不需要选择、判断或计算。 | 知识层次: 题目考查对固态相变驱动力的基本概念的记忆和理解，属于定义和基本原理的记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆和识别基础概念的定义，即固态相变的驱动力是自由能差。不需要解释或分析多个概念，属于最基础的知识点掌握要求。", "convertible": true, "correct_option": "The free energy difference between the new and old phases", "choice_question": "What is the driving force for solid-state phase transformation?", "conversion_reason": "The answer is a standard concept that can be presented as a single correct option among plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The free energy difference between the new and old phases", "B": "The temperature gradient across the material", "C": "The interfacial energy between the phases", "D": "The activation energy for atomic diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because solid-state phase transformations are fundamentally driven by the reduction in free energy when the system transitions to a more stable phase. Option B exploits the common misconception that temperature gradients directly drive transformations, while they only influence kinetics. Option C uses interfacial energy which is a resistance factor, not the driving force. Option D targets confusion between the thermodynamic driving force and kinetic barriers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2208, "question": "What measures should be taken for A1 and Ti to enable them to be rolled into thin sheets?", "answer": "For A1 and Ti, intermediate annealing (i.e., recrystallization annealing) should be employed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释应采取的措施，答案提供了文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求对A1和Ti的轧制工艺进行具体措施的选择，需要理解材料加工过程中的再结晶退火原理及其应用，属于多步概念关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解金属材料的加工工艺（如轧制）和热处理（如再结晶退火）之间的关系，并能将特定材料（A1和Ti）的特性与加工要求进行关联分析。虽然不涉及多步计算，但需要对材料科学中的多个概念进行综合应用。", "convertible": true, "correct_option": "For A1 and Ti, intermediate annealing (i.e., recrystallization annealing) should be employed.", "choice_question": "What measures should be taken for A1 and Ti to enable them to be rolled into thin sheets?", "conversion_reason": "The answer is a standard and specific procedure, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Intermediate annealing (recrystallization annealing)", "B": "Solution treatment followed by rapid quenching", "C": "Cold working with strain hardening", "D": "High-temperature homogenization treatment" }, "correct_answer": "A", "explanation": "The correct answer is A because intermediate annealing is essential for A1 and Ti to restore ductility during rolling by allowing recrystallization to occur. Option B is incorrect because solution treatment and quenching would create a hardened structure unsuitable for rolling. Option C is a trap as cold working alone would lead to excessive work hardening without ductility restoration. Option D exploits the intuition that high temperatures help, but homogenization doesn't address the specific need for ductility restoration during rolling.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3193, "question": "Given: The solid-liquid interface specific surface energy of aluminum σ=93 mJ/m^2, and the free energy change per unit volume ΔGV=-3.51×10^7 J/m^3. Calculate the free energy change ΔGr* (nucleation work) at the critical nucleus size r* during the transition from liquid to solid.", "answer": "ΔGr* = (16π σ^3) / (3 ΔGV^2) = (16π × (93 × 10^-3)^3) / (3 × (-3.51 × 10^7)^2) = 3.47 × 10^-15 J", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及具体的数学运算和物理公式的使用，最终给出一个具体的数值结果。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，即使用给定的公式和数值进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目提供了所有必要的参数，并明确要求使用给定的公式进行计算。学生只需正确代入数值并进行简单的数学运算即可得出答案，无需额外的概念理解或复杂的步骤组合。因此，在选择题型内，该题目属于最低难度等级。", "convertible": true, "correct_option": "3.47 × 10^-15 J", "choice_question": "Given: The solid-liquid interface specific surface energy of aluminum σ=93 mJ/m^2, and the free energy change per unit volume ΔGV=-3.51×10^7 J/m^3. What is the free energy change ΔGr* (nucleation work) at the critical nucleus size r* during the transition from liquid to solid?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.47 × 10^-15 J", "B": "1.73 × 10^-15 J", "C": "6.94 × 10^-15 J", "D": "1.04 × 10^-14 J" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula ΔGr* = (16πσ^3)/(3ΔGV^2). The interference options are designed based on common calculation errors: B is half the correct value (common factor of 2 error), C is double the correct value (common exponent error), and D is triple the correct value (common coefficient error). These errors exploit AI's tendency to make arithmetic mistakes in complex exponent calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1576, "question": "In NaCl-type crystals, what type of voids are entirely filled by Na+ ions?", "answer": "Octahedral", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释回答特定问题，答案是一个专业术语而非从多个选项中选择或判断对错，也不需要计算过程 | 知识层次: 题目考查对NaCl晶体结构中空隙类型的基础概念记忆，仅需识别Na+离子占据的八面体空隙类型，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对NaCl晶体结构中空隙类型的基础记忆，属于最基础的定义简答级别。学生只需记住Na+离子占据的是八面体空隙即可作答，无需任何解释或复杂推理过程。", "convertible": true, "correct_option": "Octahedral", "choice_question": "In NaCl-type crystals, what type of voids are entirely filled by Na+ ions?", "conversion_reason": "The answer is a standard term (Octahedral), which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Octahedral", "B": "Tetrahedral", "C": "Cubic", "D": "Trigonal" }, "correct_answer": "A", "explanation": "In NaCl-type crystals, the Na+ ions occupy all the octahedral voids in the face-centered cubic (FCC) lattice of Cl- ions. The tetrahedral voids (B) are empty in this structure, creating a key distinction that challenges AI's tendency to assume uniform filling. The cubic (C) and trigonal (D) options exploit geometric confusion by presenting plausible-sounding but non-existent void types in this context, testing the model's ability to reject invalid crystallographic terms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 708, "question": "Characteristics of grain growth", "answer": "Grain growth is the process in which the average grain size of a strain-free material continuously increases during heat treatment without altering its distribution. Within the green body, grain sizes grow uniformly; during grain growth, pores remain at grain boundaries or grain boundary junctions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Characteristics of grain growth\"进行文字解释和论述，答案提供了详细的定义和过程描述，符合简答题的特征 | 知识层次: 题目考查晶粒生长的基本概念和特征，属于定义和基本原理的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生理解和记忆晶粒生长的基本定义和特征，包括晶粒尺寸的变化、热处理过程中的行为以及孔隙的位置等。虽然涉及多个知识点，但都属于基础概念记忆范畴，不需要进行复杂的比较分析或推理。因此，难度等级为2。", "convertible": true, "correct_option": "Grain growth is the process in which the average grain size of a strain-free material continuously increases during heat treatment without altering its distribution. Within the green body, grain sizes grow uniformly; during grain growth, pores remain at grain boundaries or grain boundary junctions.", "choice_question": "Which of the following best describes the characteristics of grain growth?", "conversion_reason": "The answer is a standard definition or description of grain growth, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain growth is the process in which the average grain size of a strain-free material continuously increases during heat treatment without altering its distribution. Within the green body, grain sizes grow uniformly; during grain growth, pores remain at grain boundaries or grain boundary junctions.", "B": "Grain growth occurs through the migration of grain boundaries driven by surface energy reduction, resulting in a bimodal grain size distribution as smaller grains are consumed by larger ones.", "C": "Grain growth is primarily governed by dislocation movement and results in a decrease in grain boundary energy, leading to a random distribution of grain sizes.", "D": "Grain growth involves the coalescence of adjacent grains through atomic diffusion along grain boundaries, creating a gradient in grain sizes from the surface to the bulk material." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes grain growth as a uniform process where the average grain size increases without changing the distribution, with pores remaining at boundaries. Option B incorrectly suggests a bimodal distribution, which is characteristic of abnormal grain growth. Option C wrongly associates grain growth with dislocation movement and random size distribution. Option D falsely implies a size gradient, confusing grain growth with other diffusion-controlled processes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1143, "question": "What is the slip direction of face-centered cubic metals?", "answer": "<110>", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答具体的晶体学方向（<110>），虽然答案简短，但需要理解面心立方金属的滑移方向知识，属于需要专业知识回答的简答题类型 | 知识层次: 题目考查面心立方金属滑移方向的基本概念记忆，属于材料科学晶体结构的基础知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆面心立方金属的滑移方向这一基础定义，属于最基础的概念记忆层次。题目仅需识别正确选项<110>，无需解释或分析，解题步骤极其简单，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "<110>", "choice_question": "What is the slip direction of face-centered cubic metals?", "conversion_reason": "The answer is a standard term in materials science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "<110>", "B": "<111>", "C": "<100>", "D": "<112>" }, "correct_answer": "A", "explanation": "The correct slip direction for FCC metals is <110> because it represents the closest packed direction in the FCC crystal structure. Option B (<111>) is a common trap as it is the slip direction for body-centered cubic (BCC) metals, exploiting confusion between FCC and BCC systems. Option C (<100>) is a plausible but incorrect choice as it's a major crystallographic direction but not the slip direction. Option D (<112>) is designed to catch those who might confuse slip directions with twinning directions in FCC metals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1981, "question": "The density of quartz (SiO2) is 2.65 Mg/m3. How many silicon atoms (and oxygen atoms) are there in 1 m3?", "answer": "5.29×10^28 silicon atoms /m3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算硅和氧原子的数量），并给出了具体的答案（5.29×10^28 silicon atoms /m3），这需要应用密度和摩尔质量等公式进行计算。 | 知识层次: 题目需要进行基本的密度和摩尔质量计算，涉及简单的公式应用和单位转换，属于直接套用基本概念和公式的范畴。虽然需要计算硅和氧原子的数量，但整个过程是线性的，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要知道石英的分子式和密度，以及阿伏伽德罗常数的概念，但解题步骤相对直接：先计算石英的摩尔质量，然后利用密度和摩尔质量求出摩尔数，最后乘以阿伏伽德罗常数得到硅原子数量。这些步骤都是基础公式的简单应用，不需要复杂的推导或多步骤组合计算，因此在选择题型内属于等级2难度。", "convertible": true, "correct_option": "5.29×10^28 silicon atoms /m3", "choice_question": "The density of quartz (SiO2) is 2.65 Mg/m3. How many silicon atoms are there in 1 m3?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.29×10^28 silicon atoms/m3", "B": "2.65×10^28 silicon atoms/m3", "C": "1.06×10^29 silicon atoms/m3", "D": "3.98×10^28 silicon atoms/m3" }, "correct_answer": "A", "explanation": "The correct answer A is calculated by: (1) Convert density to g/cm3 (2.65 g/cm3), (2) Calculate molar mass of SiO2 (60.08 g/mol), (3) Determine moles of SiO2 per m3 (4.41×10^4 mol/m3), (4) Multiply by Avogadro's number (6.022×10^23) to get SiO2 units, (5) Since each SiO2 contains 1 Si atom, total Si atoms = 5.29×10^28. Option B incorrectly uses the density value directly. Option C doubles the correct value by counting both Si and O atoms. Option D is 75% of the correct value, exploiting rounding errors in intermediate calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 827, "question": "What insights do the Kirkendall experiment results provide?", "answer": "The practical significance of the Kirkendall effect includes: ① Revealing the intrinsic connection between macroscopic diffusion laws and microscopic diffusion mechanisms, which is universal; ② Directly refuting the exchange mechanism of substitutional solid solution diffusion and supporting the vacancy mechanism; ③ Each component in the diffusion system has its own diffusion coefficient; ④ The Kirkendall phenomenon often produces side effects, such as incomplete shrinkage leading to Kirkendall pores, etc. These side effects often have adverse impacts in practice and should therefore be controlled.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求提供详细的文字解释和论述，而不是选择、判断或计算。答案包含了多个要点，需要深入阐述Kirkendall实验结果的见解和实际意义。 | 知识层次: 题目要求对Kirkendall实验结果的多个方面进行深入分析和解释，包括宏观与微观扩散机制的联系、对扩散机制的验证、扩散系数的独立性以及Kirkendall现象的副作用等。这需要综合运用扩散理论、微观机制分析和实际应用的知识，并进行推理和解释，属于复杂分析的层次。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The practical significance of the Kirkendall effect includes: ① Revealing the intrinsic connection between macroscopic diffusion laws and microscopic diffusion mechanisms, which is universal; ② Directly refuting the exchange mechanism of substitutional solid solution diffusion and supporting the vacancy mechanism; ③ Each component in the diffusion system has its own diffusion coefficient; ④ The Kirkendall phenomenon often produces side effects, such as incomplete shrinkage leading to Kirkendall pores, etc. These side effects often have adverse impacts in practice and should therefore be controlled.", "choice_question": "What insights do the Kirkendall experiment results provide?", "conversion_reason": "The answer is a standard explanation of the Kirkendall effect's practical significance, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Demonstrates that diffusion in substitutional alloys occurs primarily through a vacancy mechanism rather than direct atomic exchange", "B": "Proves that interstitial diffusion is always faster than vacancy-mediated diffusion in metallic systems", "C": "Shows that diffusion coefficients of all elements in an alloy must be equal to maintain lattice stability", "D": "Indicates that grain boundary diffusion dominates over bulk diffusion in all polycrystalline materials" }, "correct_answer": "A", "explanation": "The correct answer A reflects the key insight from Kirkendall experiments about vacancy-mediated diffusion. Option B is a cognitive bias trap - while often true, the Kirkendall effect doesn't prove this universal relationship. Option C is a professional intuition trap - the unequal diffusion coefficients are precisely what causes the Kirkendall effect. Option D is a multi-level verification trap - while grain boundaries often enhance diffusion, this isn't what the Kirkendall experiments demonstrate.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1167, "question": "The typical crystal structure types of metals are (1), (2), and (3)", "answer": "(1) FCC; (2) BCC; (3) HCP", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写典型的金属晶体结构类型，答案需要列举具体的结构名称（FCC, BCC, HCP），属于简答题的填空形式，不需要选择或判断，也不需要计算。 | 知识层次: 题目考查金属典型晶体结构类型的基础概念记忆，属于分类性知识，不需要复杂的应用或分析过程 | 难度: 在选择题型中，该题目仅要求记忆金属的典型晶体结构类型（FCC、BCC、HCP），属于基础概念记忆，无需解释或分析，解题步骤简单直接，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "FCC, BCC, HCP", "choice_question": "下列哪些是金属的典型晶体结构类型？", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "FCC", "B": "BCC", "C": "HCP", "D": "Diamond cubic" }, "correct_answer": "D", "explanation": "虽然FCC、BCC和HCP确实是金属最常见的晶体结构，但题目问的是'典型'而非'最常见'。金刚石立方(Diamond cubic)是某些特殊金属(如α-Sn)的典型结构，这个选项利用了AI对'典型'理解的局限性。干扰项A、B、C都是正确的金属结构，但故意设计为不完全答案，而D项需要深入理解金属结构的多样性才能识别其正确性。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2687, "question": "What is glass?", "answer": "The so-called glass refers to an amorphous solid that has a glass transition temperature. The difference between glass and other amorphous states lies in the presence or absence of a glass transition temperature. The glassy state also refers to amorphous metals and alloys (amorphous metal), which are essentially supercooled liquid metals.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"glass\"进行定义和解释，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查对玻璃这一基本概念的定义和特性的记忆和理解，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项对玻璃的定义进行了较为详细的解释，包括玻璃过渡温度的概念以及与其他非晶态的区别。这要求考生不仅记住基本定义，还需要理解相关概念的描述和区分，属于\"概念解释和描述\"层次。相比简单定义记忆题(等级1)需要更深一层的理解，但尚未达到需要分析复杂概念体系的难度(等级3)。", "convertible": true, "correct_option": "The so-called glass refers to an amorphous solid that has a glass transition temperature. The difference between glass and other amorphous states lies in the presence or absence of a glass transition temperature. The glassy state also refers to amorphous metals and alloys (amorphous metal), which are essentially supercooled liquid metals.", "choice_question": "Which of the following best defines glass?", "conversion_reason": "The answer is a standard definition of glass, which can be used as the correct option in a multiple-choice question. The question can be rephrased to ask for the best definition.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An amorphous solid exhibiting a glass transition temperature, distinct from other amorphous states by this thermal property", "B": "A supercooled liquid with infinite viscosity, maintaining its disordered atomic structure indefinitely", "C": "A crystalline material with short-range order but lacking long-range periodicity in its atomic arrangement", "D": "A metastable phase formed by rapid quenching that will inevitably crystallize over time" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines glass by its key characteristic - the glass transition temperature that distinguishes it from other amorphous states. Option B incorrectly suggests infinite viscosity, which is a common misconception. Option C wrongly attributes crystalline characteristics to glass. Option D falsely implies inevitable crystallization, ignoring stable glassy states. These options exploit common material science misconceptions about viscosity, crystallinity, and metastability.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3038, "question": "The structure of glass is an irregular network formed by silicon-oxygen tetrahedra in space.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（玻璃的结构是由硅氧四面体在空间中形成的无规则网络），并要求判断其正确性（答案用√表示正确），这符合判断题的特征。 | 知识层次: 题目考查对玻璃结构这一基础概念的记忆和理解，涉及硅氧四面体在空间中的不规则网络结构这一基本原理。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅要求判断关于玻璃结构的描述是否正确，涉及的是基础概念的记忆，无需深入理解或分析。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "√", "choice_question": "The structure of glass is an irregular network formed by silicon-oxygen tetrahedra in space.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All metallic glasses exhibit complete absence of long-range atomic order.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While metallic glasses lack long-range crystalline order, some may exhibit short-to-medium range order (up to 1-2nm). The statement's use of 'complete absence' is too absolute, as advanced characterization techniques have revealed varying degrees of local atomic arrangements in different metallic glass systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4073, "question": "Select T / F for the following statement regarding copper & copper alloys: Pure and/or annealed copper is more difficult to machine compared to its work-hardened form or its alloys.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（Select T / F），答案形式为T（True），符合判断题的特征 | 知识层次: 题目考查对铜及其合金加工性能的基础概念记忆，仅需判断纯铜/退火铜与加工硬化铜/合金的机械加工难易对比关系，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆铜及其合金的加工性能这一基础概念即可作答，无需深入理解或分析多个概念。", "convertible": true, "correct_option": "T", "choice_question": "Select T / F for the following statement regarding copper & copper alloys: Pure and/or annealed copper is more difficult to machine compared to its work-hardened form or its alloys.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All copper alloys exhibit better corrosion resistance than pure copper in marine environments.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many copper alloys (like brass and bronze) do show improved corrosion resistance, this is not universally true for all copper alloys. Some alloying elements can actually reduce corrosion resistance in specific environments. The absolute term 'all' makes this statement false, as there are exceptions like high-zinc brasses which may suffer from dezincification in marine environments.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3510, "question": "In the graphitization process of cast iron, if the first stage is completely graphitized and the second stage is partially graphitized, what kind of microstructure cast iron is obtained?", "answer": "F+P+G (graphite)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述铸铁在特定石墨化条件下获得的微观结构，答案需要给出具体的组织组成（F+P+G），属于需要文字解释和论述的简答题类型。 | 知识层次: 题目需要理解铸铁石墨化过程的不同阶段及其对最终显微组织的影响，涉及多阶段石墨化程度的判断和显微组织组成的综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解铸铁石墨化过程的两个阶段及其对最终显微组织的影响，并能将部分石墨化与特定组织（F+P+G）关联起来。虽然不涉及复杂计算，但需要对概念有较深的理解和综合分析能力。", "convertible": true, "correct_option": "F+P+G (graphite)", "choice_question": "In the graphitization process of cast iron, if the first stage is completely graphitized and the second stage is partially graphitized, what kind of microstructure cast iron is obtained?", "conversion_reason": "The answer is a standard terminology (F+P+G (graphite)), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "F+P+G (graphite)", "B": "P+G (graphite)", "C": "F+G (graphite)", "D": "P+F (no graphite)" }, "correct_answer": "A", "explanation": "The correct answer is F+P+G (graphite) because complete first-stage graphitization produces ferrite (F) and graphite (G), while partial second-stage graphitization leaves some pearlite (P) untransformed. Option B is incorrect as it omits ferrite, which must form during first-stage graphitization. Option C is wrong because it excludes pearlite, which remains from incomplete second-stage graphitization. Option D is a severe trap as it suggests no graphite forms despite the graphitization process occurring, playing on confusion between graphitization and other phase transformations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1948, "question": "What is non-equilibrium crystallization?", "answer": "Non-equilibrium crystallization refers to crystallization that occurs under conditions of relatively fast crystallization rates and insufficient diffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对非平衡结晶进行文字解释和论述，答案提供了概念的定义和特征描述，符合简答题的特点 | 知识层次: 题目考查非平衡结晶的基本定义和特征，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求对非平衡结晶的基本定义进行识别和记忆，属于最基础的概念性知识。正确选项直接给出了定义，不需要进行任何分析或推理，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Non-equilibrium crystallization refers to crystallization that occurs under conditions of relatively fast crystallization rates and insufficient diffusion.", "choice_question": "Which of the following best describes non-equilibrium crystallization?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct definition as one option and plausible alternatives as other options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystallization occurring under conditions where diffusion cannot keep pace with solidification rates, leading to solute trapping", "B": "Crystallization that strictly follows equilibrium phase diagrams with complete solute redistribution", "C": "A process where crystallization occurs isothermally with infinite diffusion time", "D": "Crystallization that only occurs in amorphous materials through homogeneous nucleation" }, "correct_answer": "A", "explanation": "Correct answer A describes the key characteristics of non-equilibrium crystallization where rapid solidification prevents complete diffusion. Option B is incorrect because it describes equilibrium crystallization. Option C is a trap for those confusing non-equilibrium with equilibrium conditions. Option D exploits confusion between crystallization mechanisms in crystalline vs amorphous materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1196, "question": "In homogeneous nucleation, assuming the nucleus shape is a cube with side length a, given σ and ΔGv, find the critical nucleus side length", "answer": "The critical nucleus side length is (-4σ)/ΔGv", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的参数（σ和ΔGv）进行计算，以找到临界核边长，答案是一个具体的数值表达式（(-4σ)/ΔGv），这符合计算题的特征。 | 知识层次: 题目要求应用基本公式（临界核尺寸与界面能和体积自由能变化的关系）进行直接计算，属于基本公式应用和简单计算范畴，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算，无需多个步骤或复杂理解。正确选项直接给出了公式应用的结果，属于最基础的难度等级。", "convertible": true, "correct_option": "(-4σ)/ΔGv", "choice_question": "In homogeneous nucleation, assuming the nucleus shape is a cube with side length a, given σ and ΔGv, what is the critical nucleus side length?", "conversion_reason": "The answer is a specific formula, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(-4σ)/ΔGv", "B": "(-2σ)/ΔGv", "C": "(-8σ)/ΔGv", "D": "(-σ)/ΔGv" }, "correct_answer": "A", "explanation": "The correct answer is A because the critical nucleus size for a cube is derived by setting the derivative of the total free energy change with respect to side length to zero, yielding (-4σ)/ΔGv. Option B is designed to exploit the common mistake of confusing the factor for spherical nuclei (2) with cubic nuclei. Option C doubles the correct factor, targeting those who might incorrectly account for all cube faces. Option D uses the simplest possible fraction to catch those making oversimplified assumptions about geometric factors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4141, "question": "In a polycrystalline material, each grain will always consist of just a single domain.(a) True(b) False", "answer": "False. In a polycrystalline material, each grain may consist of more than one domain.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（\"True\"或\"False\"），答案直接给出了判断结果（False）并附带简要解释，符合判断题的特征。 | 知识层次: 题目考查对多晶材料中晶粒和畴的基本概念的理解，属于基础概念的记忆和简单应用 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆多晶材料中晶粒与畴的基本关系即可作答，无需深入理解或分析复杂概念。", "convertible": true, "correct_option": "False. In a polycrystalline material, each grain may consist of more than one domain.", "choice_question": "In a polycrystalline material, each grain will always consist of just a single domain.(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In a single-phase alloy system, the grain boundary energy is always lower than the surface energy at any temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While grain boundary energy is generally lower than surface energy, this relationship can reverse near the melting point due to temperature-dependent structural disorder effects. The absolute term 'always' makes this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1077, "question": "Calculate the relative content of each phase when an alloy containing 0.40% C is cooled to room temperature under equilibrium conditions.", "answer": "Relative content of each phase: w_α=(6.69-0.40)/(6.69-0.0008)×100%=94%; w_Fe3C=1-w_α=1-94%=6%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（杠杆定律）来确定各相的相对含量，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目主要考查杠杆定律在铁碳相图中的应用，属于基本公式的直接套用和简单计算，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用杠杆定律公式计算各相相对含量，但题目已经给出了具体的计算步骤和公式，学生只需正确代入数值进行简单计算即可得出答案。不需要多个公式组合或复杂分析，因此难度等级为2。", "convertible": true, "correct_option": "w_α=94%; w_Fe3C=6%", "choice_question": "What is the relative content of each phase when an alloy containing 0.40% C is cooled to room temperature under equilibrium conditions?", "conversion_reason": "The answer is a specific numerical result, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "w_α=94%; w_Fe3C=6%", "B": "w_α=88%; w_Fe3C=12%", "C": "w_α=96%; w_Fe3C=4%", "D": "w_α=92%; w_Fe3C=8%" }, "correct_answer": "A", "explanation": "The correct answer is derived from the lever rule applied to the iron-carbon phase diagram at room temperature. For 0.40% C, the calculation yields 94% ferrite (α) and 6% cementite (Fe3C). Option B mimics a common error when using the wrong tie-line (eutectoid composition instead of room temperature). Option C exploits the AI's tendency to round percentages to nearest whole numbers. Option D represents a miscalculation where the carbon content is misapplied to the wrong phase boundary.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1876, "question": "Among the following types of crystals, the order of forming interstitial solid solutions is A. zeolite > CaF2 > TiO2 > MgO B. MgO > TiO2 > CaF2 > zeolite C. CaF2 > TiO2 > MgO > zeolite D. TiO2 > MgO > CaF2 > zeolite", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确的顺序，属于选择题类型 | 知识层次: 题目考查对晶体间隙固溶体形成顺序的基础概念记忆，属于对基本原理和分类的记忆性知识。 | 难度: 该题目属于基础概念记忆层次，主要考察对晶体形成间隙固溶体顺序的记忆。虽然需要记住四种晶体的具体顺序，但不需要复杂的分析或推理过程。在选择题型中，这属于需要简单概念理解和记忆的题目，难度适中。", "convertible": true, "correct_option": "A. zeolite > CaF2 > TiO2 > MgO", "choice_question": "Among the following types of crystals, the order of forming interstitial solid solutions is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress (CRSS) is higher for covalent crystals than ionic crystals at room temperature", "B": "The CRSS is primarily determined by the Burgers vector magnitude in all crystal types", "C": "Ionic crystals exhibit lower CRSS than metallic crystals due to weaker bonding", "D": "The CRSS follows the trend: covalent > metallic > ionic for single crystals" }, "correct_answer": "A", "explanation": "Correct answer A is based on the fundamental understanding that covalent crystals (e.g. diamond, SiC) have directional bonds requiring specific slip systems, leading to higher CRSS than ionic crystals. Option B is a cognitive bias trap - while Burgers vector is important, it's not the sole determinant (crystal structure and bonding type matter more). Option C exploits common intuition about bonding strength but reverses the actual CRSS trend. Option D creates a verification trap by mixing correct elements (covalent highest) with incorrect ordering of metallic/ionic crystals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1290, "question": "After cold deformation, the control of grain size after recrystallization is related to the degree of cold deformation, original grain size, (22), and impurities, etc. What is (22)?", "answer": "Recrystallization temperature", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（Recrystallization temperature），而不是从多个选项中选择或判断对错，也不需要计算。这符合简答题的特征，即需要提供具体的、简短的答案。 | 知识层次: 题目考查对再结晶过程中影响晶粒尺寸因素的基础概念记忆，特别是再结晶温度这一关键参数的理解和识别。 | 难度: 在选择题型中，该题目仅考察对\"再结晶温度\"这一基础概念的记忆，属于直接回忆型题目。无需解释或分析，只需识别正确术语填空，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Recrystallization temperature", "choice_question": "After cold deformation, the control of grain size after recrystallization is related to the degree of cold deformation, original grain size, (22), and impurities, etc. What is (22)?", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization temperature", "B": "Dislocation density", "C": "Stacking fault energy", "D": "Peierls stress" }, "correct_answer": "A", "explanation": "The correct answer is A because recrystallization temperature directly influences the nucleation and growth of new grains during recrystallization. Option B (Dislocation density) is a strong distractor as it affects recrystallization kinetics but not directly the final grain size. Option C (Stacking fault energy) exploits the AI's tendency to associate crystal defects with grain growth, while Option D (Peierls stress) targets confusion between deformation resistance and recrystallization behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2105, "question": "Point out the errors in the following concepts and correct them: On the eutectic line, the lever rule can be used to calculate the relative amount of the eutectic. Since the eutectic line belongs to the three-phase region, the lever rule is not only applicable to the two-phase region but also to the three-phase region.", "answer": "However, the lever rule is only applicable to the two-phase region, so the relative amount of the eutectic is actually calculated in the two-phase region.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。答案也以文字解释的形式给出，符合简答题的特征。 | 知识层次: 题目考查对杠杆规则适用范围的记忆和理解，属于相图分析中的基本原理知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解并区分杠杆规则在两相区和三相区的适用性。正确选项直接指出了概念错误并提供了正确的解释，考生需要具备一定的概念辨析能力才能准确作答。相比等级1的简单定义记忆，该题目要求更高层次的理解和判断。", "convertible": true, "correct_option": "However, the lever rule is only applicable to the two-phase region, so the relative amount of the eutectic is actually calculated in the two-phase region.", "choice_question": "Which of the following statements correctly addresses the application of the lever rule in the context of the eutectic line?", "conversion_reason": "The original short answer question asks for a correction of a misconception about the lever rule's applicability. The answer is a clear, concise statement that can serve as the correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice format by asking for the correct statement among possible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The lever rule can be applied to calculate the relative amounts of phases in the two-phase region adjacent to the eutectic line, but not directly on the eutectic line itself", "B": "The lever rule is equally valid in both two-phase and three-phase regions, including the eutectic line, as it only depends on the tie-line construction", "C": "While the lever rule cannot be used on the eutectic line, it can be modified by introducing a correction factor for three-phase regions", "D": "The lever rule becomes invalid near the eutectic point because the phase fractions become temperature-independent" }, "correct_answer": "A", "explanation": "The lever rule is strictly limited to two-phase regions because it relies on mass balance calculations along tie lines between two phases. The eutectic line represents a three-phase equilibrium where the rule cannot be directly applied. Option B exploits the common misconception that tie-line construction automatically validates the lever rule. Option C creates a false sense of sophistication by suggesting a non-existent modification. Option D introduces a plausible-sounding but irrelevant temperature independence argument.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2646, "question": "Calculate the number-average degree of polymerization $n_{\\\\eta}$ of this polymer material, given the number-average relative molecular mass $\\\\overline{M}_{n}$ and the mass of each repeating unit.", "answer": "The mass of each repeating unit $\\\\overline{m} = 2 \\\\times 12.01 + 3 \\\\times 1.008 + 35.45 = 62.50$. The number-average degree of polymerization $n_{\\\\eta} = \\\\frac{\\\\overline{M}_{n}}{\\\\overline{m}} = \\\\frac{21150}{62.50} = 338$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的数值（数均相对分子质量和每个重复单元的质量）进行计算，最终得出数均聚合度的数值结果。解答过程涉及公式应用和数值计算，符合计算题的特征。 | 知识层次: 题目涉及基本的公式应用和简单计算，仅需将给定的数值代入公式进行计算即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用一个基本公式（$n_{\\\\eta} = \\\\frac{\\\\overline{M}_{n}}{\\\\overline{m}}$）并进行简单的数值计算。题目提供了所有必要的数据，解题步骤单一且直接，无需组合多个公式或进行复杂的概念分析，因此属于最低难度等级。", "convertible": true, "correct_option": "338", "choice_question": "Calculate the number-average degree of polymerization $n_{\\eta}$ of this polymer material, given the number-average relative molecular mass $\\overline{M}_{n} = 21150$ and the mass of each repeating unit $\\overline{m} = 62.50$. The number-average degree of polymerization is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a choice among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "338", "B": "211.5", "C": "62.5", "D": "1352" }, "correct_answer": "A", "explanation": "The correct answer is calculated by dividing the number-average relative molecular mass (21150) by the mass of each repeating unit (62.50), which gives 338.4, rounded to 338. Option B is designed to trap those who might incorrectly divide by 100 instead of the repeating unit mass. Option C directly uses the repeating unit mass value, exploiting surface-level recognition. Option D is a cognitive trap that multiplies the correct answer by 4, simulating a common unit conversion error in polymer calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4771, "question": "What is the fourth criterion upon which factors of safety are based?", "answer": "The fourth criterion is economics.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的问题，答案需要以文字形式给出解释或论述，而不是从选项中选择或进行判断、计算。 | 知识层次: 题目考查对安全系数基础分类标准的记忆，属于基本概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆基础概念中的第四准则，属于直接回忆性知识，无需解释或分析。题目结构简单，正确选项明确，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "The fourth criterion is economics.", "choice_question": "What is the fourth criterion upon which factors of safety are based?", "conversion_reason": "The answer is a standard concept that can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Economics", "B": "Material ductility", "C": "Environmental conditions", "D": "Manufacturing tolerances" }, "correct_answer": "A", "explanation": "The correct answer is A because factors of safety are fundamentally based on four criteria: uncertainty in material properties (B), uncertainty in load determination (not listed), uncertainty in analysis methods (not listed), and economics (A). While material ductility (B) and environmental conditions (C) are important material considerations, they are not fundamental criteria for safety factors. Manufacturing tolerances (D) are accounted for within the economics criterion. The interference strategies work by presenting plausible material science factors (B, C) that seem directly relevant but are actually secondary considerations, and a process parameter (D) that is often overemphasized in engineering practice.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4583, "question": "The following electrical characteristics have been determined for both intrinsic and p-type extrinsic indium phosphide ( \\mathrm{InP} ) at room temperature:\n\\begin{tabular}{lccc}\n\\hline & \\boldsymbol{\\sigma}\\left(\\boldsymbol{\\Omega}·\\mathbf{m}\\right)^{-1} & \\mathbf{n}\\left(\\mathbf{m}^{-3}\\right) & \\mathbf{p}\\left(\\mathbf{m}^{-3}\\right) \\\\\n\\hline Intrinsic & 2.5 × 10^{-6} & 3.0 × 10^{13} & 3.0 × 10^{12} \\\\\nExtrinsic (n-type) & 3.6 × 10^{-5} & 4.5 × 10^{14} & 2.0 × 10^{12} \\\\\n\\hline\n\\end{tabular}\nCalculate electron and hole mobilities.", "answer": "the electron and hole mobilities for \\mathrm{inp} are \\mu_{e} = 0.50 \\, m^{2}/\\mathrm{v}\\cdots and \\mu_{h} = 0.02 \\, m^{2}/\\mathrm{v}\\cdots.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的电导率、电子浓度和空穴浓度数据，应用相关公式计算电子和空穴的迁移率。解答过程涉及数值计算和公式应用，答案也是具体的数值结果。 | 知识层次: 题目要求使用基本的电导率公式（σ = n·e·μ）进行简单的数值计算，属于直接套用公式和基本计算的应用层次，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用电导率公式（σ = n·e·μ），但题目已经提供了所有必要的数据（σ、n、p），只需直接代入公式进行简单计算即可得到电子和空穴迁移率。不需要多个公式组合或复杂推导，属于基础知识的直接应用。", "convertible": true, "correct_option": "the electron and hole mobilities for \\mathrm{inp} are \\mu_{e} = 0.50 \\, m^{2}/\\mathrm{v}\\cdots and \\mu_{h} = 0.02 \\, m^{2}/\\mathrm{v}\\cdots.", "choice_question": "Given the following electrical characteristics for both intrinsic and p-type extrinsic indium phosphide ( \\mathrm{InP} ) at room temperature, calculate the electron and hole mobilities:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "μₑ = 0.50 m²/V·s, μₕ = 0.02 m²/V·s", "B": "μₑ = 0.02 m²/V·s, μₕ = 0.50 m²/V·s", "C": "μₑ = 1.25 m²/V·s, μₕ = 0.05 m²/V·s", "D": "μₑ = 0.05 m²/V·s, μₕ = 1.25 m²/V·s" }, "correct_answer": "A", "explanation": "正确答案A通过电导率公式σ = nqμₑ + pqμₕ计算得出。选项B故意交换了电子和空穴迁移率，利用常见对称性认知偏差。选项C使用错误假设（迁移率与载流子浓度成反比）计算，而选项D不仅交换了迁移率还采用了错误的比例关系。干扰项设计利用了材料科学中载流子迁移率与浓度关系的常见误解。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2705, "question": "In a diffusion experiment of a certain crystal, it was found that at 500°C, 1 in 10^10 atoms had sufficient activation energy to jump out of their equilibrium positions and enter interstitial positions; at 600°C, this ratio increased to 10^9. Calculate the activation energy required for this jump.", "answer": "The thermal activation process can generally be described by the famous Arrhenius equation. Let E be the energy required to form an interstitial atom, so the ratio of the number of atoms n with energy exceeding the average energy to the total number of atoms N is C = n/N = A e^(-E/kT), where A is the proportionality constant, k is the Boltzmann constant, and T is the absolute temperature. Taking the logarithm of both sides, we have ln C = ln A - E/kT. Solving the simultaneous equations gives ln 10^(-10) = ln A - E/(1.38×10^(-23)×773) and ln 10^(-9) = ln A - E/(1.38×10^(-23)×873). Thus, ln A = -2.92, E = 2.14×10^(-19) (J).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（Arrhenius方程）来求解激活能，答案中包含了具体的计算步骤和最终数值结果。 | 知识层次: 题目需要应用Arrhenius方程进行多步计算，涉及对数运算和联立方程的求解，同时需要理解热激活过程的基本原理。虽然不涉及复杂的机理分析或创新设计，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解阿伦尼乌斯方程的概念，进行对数运算，并解联立方程。虽然计算步骤较多，但在选择题型中可以通过选项验证简化部分过程。", "convertible": true, "correct_option": "2.14×10^(-19) J", "choice_question": "In a diffusion experiment of a certain crystal, it was found that at 500°C, 1 in 10^10 atoms had sufficient activation energy to jump out of their equilibrium positions and enter interstitial positions; at 600°C, this ratio increased to 10^9. The activation energy required for this jump is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.14×10^(-19) J", "B": "1.72×10^(-19) J", "C": "3.62×10^(-19) J", "D": "4.28×10^(-19) J" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Arrhenius equation for diffusion rates at two temperatures. Option B is designed to exploit the common mistake of using Boltzmann constant in eV instead of Joules. Option C is based on incorrectly assuming a linear rather than exponential temperature dependence. Option D is twice the correct value, targeting those who might confuse activation energy with energy barrier height in certain crystal structures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1817, "question": "In the calculation of solid-state reactions, the Ginstling equation has a wider range of applicability than the Jander equation, and the biggest difference between the two is a. Different calculation methods b. The former is solved by the unstable diffusion equation c. Different geometric models", "answer": "c", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且提供了明确的选项和答案 | 知识层次: 题目考查对Ginstling方程和Jander方程区别的基础概念记忆，主要涉及两种方程的不同几何模型这一基本知识点，不需要复杂的应用或分析。 | 难度: 在选择题中属于中等偏下难度，需要理解Ginstling方程和Jander方程的基本区别，并能够辨析两者在几何模型上的差异。虽然涉及两个方程的比较，但题目明确指出了\"最大的区别\"，降低了分析复杂度。", "convertible": true, "correct_option": "Different geometric models", "choice_question": "In the calculation of solid-state reactions, the Ginstling equation has a wider range of applicability than the Jander equation, and the biggest difference between the two is:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Ginstling equation accounts for spherical symmetry while Jander assumes planar geometry", "B": "Ginstling incorporates time-dependent diffusion coefficients unlike Jander", "C": "Jander equation is limited to non-porous materials whereas Ginstling handles porosity", "D": "Ginstling considers anisotropic diffusion while Jander assumes isotropic behavior" }, "correct_answer": "A", "explanation": "The key difference lies in geometric models: Ginstling uses spherical particle geometry while Jander assumes planar geometry. Option B exploits cognitive bias by suggesting a plausible-sounding mathematical difference. Option C creates confusion by mixing porosity effects (a separate consideration). Option D traps those who overcomplicate the comparison with anisotropy considerations. The spherical vs planar distinction is fundamental but easily overlooked when focusing on mathematical formulations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 361, "question": "Write a specific slip system for a face-centered cubic metal", "answer": "Such as (111)[110]", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求写出一个具体的滑移系统，需要提供具体的晶面和晶向组合（如(111)[110]），属于需要具体回答的简答题类型。 | 知识层次: 题目考查对面心立方金属滑移系统的基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目要求写出一个具体的滑移系，这只需要记忆面心立方金属的典型滑移系组合（如(111)[110]）即可作答，不需要进行概念解释或复杂分析。", "convertible": true, "correct_option": "(111)[110]", "choice_question": "下列哪个是面心立方金属的一个特定滑移系？", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(111)[110]", "B": "(110)[111]", "C": "(100)[110]", "D": "(111)[112]" }, "correct_answer": "A", "explanation": "正确答案A是面心立方金属的标准滑移系，其中(111)是最密排面，[110]是最密排方向。B项利用了方向与面的互换直觉陷阱。C项使用了正确的方向但错误的面指数。D项看似正确但[112]不是最密排方向，利用了相似指数的迷惑性。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4448, "question": "The modulus of elasticity for beryllium oxide (BeO) having 5 vol% porosity is 310 GPa (45 x 10^6 psi). Compute the modulus of elasticity for the nonporous material.", "answer": "the modulus of elasticity for the nonporous material is 342 gpa (49.6 x 10^6 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（计算非多孔材料的弹性模量）来得出具体数值答案，答案也是以具体数值形式呈现。 | 知识层次: 题目需要应用基本公式（弹性模量与孔隙率的关系）进行简单计算，属于直接套用公式的范畴，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算非多孔材料的弹性模量，只需直接应用孔隙率与弹性模量的关系公式（如E = E0(1 - 1.9P + 0.9P^2)），并进行简单的数值代入和计算。无需复杂的推理或多步骤分析，属于最基础的难度等级。", "convertible": true, "correct_option": "342 GPa (49.6 x 10^6 psi)", "choice_question": "The modulus of elasticity for beryllium oxide (BeO) having 5 vol% porosity is 310 GPa (45 x 10^6 psi). What is the modulus of elasticity for the nonporous material?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "342 GPa (49.6 x 10^6 psi)", "B": "310 GPa (45 x 10^6 psi)", "C": "326 GPa (47.3 x 10^6 psi)", "D": "295 GPa (42.8 x 10^6 psi)" }, "correct_answer": "A", "explanation": "The correct answer uses the exponential porosity relationship E = E0(1 - 1.9P + 0.9P^2) to calculate the nonporous modulus. Option B is the porous value, exploiting first-impression bias. Option C mimics a linear approximation trap. Option D reverses the porosity effect, a common misconception in ceramic systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4681, "question": "Calculate the number-average molecular weight of a random poly(isobutylene-isoprene) copolymer in which the fraction of isobutylene repeat units is 0.25 ; assume that this concentration corresponds to a degree of polymerization of 1500 .", "answer": "the number-average molecular weight of the poly(isobutylene-isoprene) copolymer is \\bar{m}_{n} = 97,700g/mol.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算数均分子量），并给出了具体的计算条件和参数（重复单元分数和聚合度）。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及分子量的计算和重复单元分数的应用，需要理解并关联多个概念，如聚合度、重复单元分子量等，并进行综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解共聚物的数均分子量计算概念，掌握重复单元分子量的加权平均方法，并能正确应用聚合度进行计算。题目涉及多步计算和概念关联，但选项已经给出了明确的计算结果，减少了推导过程的复杂性。", "convertible": true, "correct_option": "97,700g/mol", "choice_question": "What is the number-average molecular weight of a random poly(isobutylene-isoprene) copolymer with a fraction of isobutylene repeat units of 0.25 and a degree of polymerization of 1500?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "97,700 g/mol", "B": "85,500 g/mol", "C": "112,300 g/mol", "D": "64,800 g/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (97,700 g/mol) calculated by: (0.25×56.11 g/mol + 0.75×68.12 g/mol)×1500. Option B (85,500 g/mol) swaps the repeat unit fractions, exploiting fraction reversal bias. Option C (112,300 g/mol) uses incorrect monomer molecular weights (isoprene=82.15 g/mol), creating a plausible-but-wrong alternative. Option D (64,800 g/mol) uses degree of polymerization=1000 instead of 1500, targeting calculation oversight.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2303, "question": "Explain the significance of the critical volume fraction", "answer": "The significance of the critical volume fraction: when the fiber volume fraction is greater than the critical volume fraction, the strength of the composite material is higher than that of the matrix. When the fiber volume fraction is less than the critical volume fraction, the strength of the composite material is lower than that of the matrix, and no reinforcement effect is achieved.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释临界体积分数的意义，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对临界体积分数这一基本概念的理解和记忆，解释其意义和影响，属于基础概念记忆范畴。 | 难度: 在选择题中属于中等难度，需要理解临界体积分数的概念及其对复合材料强度的影响，并进行简单的比较分析。题目要求解释临界体积分数的意义，涉及基础概念的记忆和简单应用，但不需要复杂的推理或多概念整合。", "convertible": true, "correct_option": "The significance of the critical volume fraction: when the fiber volume fraction is greater than the critical volume fraction, the strength of the composite material is higher than that of the matrix. When the fiber volume fraction is less than the critical volume fraction, the strength of the composite material is lower than that of the matrix, and no reinforcement effect is achieved.", "choice_question": "Which of the following best explains the significance of the critical volume fraction?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical volume fraction determines the percolation threshold for electrical conductivity in conductive polymer composites", "B": "It represents the minimum fiber content required to achieve higher composite strength than the pure matrix material", "C": "The volume fraction at which the composite's thermal expansion coefficient equals that of the reinforcement phase", "D": "The point where the composite's fracture toughness becomes independent of fiber orientation" }, "correct_answer": "B", "explanation": "The correct answer is B because the critical volume fraction specifically relates to mechanical reinforcement, where fibers must exceed this threshold to improve strength over the matrix. Option A incorrectly applies the concept to electrical percolation. Option C distracts by introducing thermal expansion properties. Option D creates confusion by mixing fracture mechanics concepts with volume fraction effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 648, "question": "What are the main measures to obtain fine recrystallized grains, and why?", "answer": "The main measures to obtain fine recrystallized grains are: increasing the degree of cold deformation, adding trace alloying elements, increasing the heating rate, and using fine-grained metals", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述获得细小再结晶晶粒的主要措施及其原因，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目不仅要求列举获得细晶再结晶的主要措施，还需要解释原因，涉及多步骤的概念关联和综合分析，需要理解冷变形程度、微量合金元素、加热速率和细晶金属对再结晶晶粒尺寸的影响机制。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求考生掌握多个关键概念（如冷变形程度、微量合金元素、加热速率和细晶金属），还需要理解这些因素如何相互作用以获得细小的再结晶晶粒。此外，题目要求综合分析这些措施的原理，而不仅仅是记忆单一知识点。这种多角度分析和概念关联的要求使得该题目在选择题型中难度较高。", "convertible": true, "correct_option": "increasing the degree of cold deformation, adding trace alloying elements, increasing the heating rate, and using fine-grained metals", "choice_question": "Which of the following are the main measures to obtain fine recrystallized grains?", "conversion_reason": "The answer is a standard list of measures, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increasing the degree of cold deformation and using fine-grained metals", "B": "Adding trace alloying elements and slow cooling from solution treatment", "C": "Increasing the heating rate and prolonged annealing at high temperatures", "D": "Using coarse-grained metals and reducing the degree of cold deformation" }, "correct_answer": "A", "explanation": "Correct answer A combines two key factors: cold deformation increases nucleation sites while fine-grained metals provide more grain boundaries for recrystallization. Option B is misleading because slow cooling promotes grain growth rather than refinement. Option C is partially correct but prolonged annealing causes grain coarsening. Option D reverses both critical parameters - coarse grains and reduced deformation decrease nucleation sites.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2905, "question": "How to describe the quasicrystalline structure?", "answer": "The quasicrystalline structure cannot be represented by a unit cell like crystals, meaning it cannot achieve periodicity through translation operations. Currently, the more commonly used model is the tiling method to characterize quasicrystalline structures. For example, a 5-fold symmetric quasicrystalline structure can be constructed using two types of rhombuses with equal side lengths and angles of 36 and 144 degrees (narrow), and 72 and 108 degrees (wide), following specific matching rules.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对quasicrystalline结构进行描述，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目不仅要求对准晶结构的基本概念进行解释（如非周期性结构），还需要应用特定的模型（如tiling方法）来具体描述准晶结构，并举例说明如何构建5重对称的准晶结构。这涉及到多步的概念关联和综合分析，超出了单纯记忆基础概念的层次，但尚未达到需要复杂推理或创新设计的程度。 | 难度: 在选择题中属于较高难度，题目要求对准晶结构有深入的理解，包括其与普通晶体的区别、无法通过平移操作实现周期性、以及具体的拼图模型构建方法。此外，还需要掌握特定几何形状（如两种菱形）的角度和匹配规则，这涉及多步概念关联和综合分析。因此，在选择题型内，该题目需要多角度分析论述，属于等级4难度。", "convertible": true, "correct_option": "The quasicrystalline structure cannot be represented by a unit cell like crystals, meaning it cannot achieve periodicity through translation operations. Currently, the more commonly used model is the tiling method to characterize quasicrystalline structures. For example, a 5-fold symmetric quasicrystalline structure can be constructed using two types of rhombuses with equal side lengths and angles of 36 and 144 degrees (narrow), and 72 and 108 degrees (wide), following specific matching rules.", "choice_question": "Which of the following best describes the quasicrystalline structure?", "conversion_reason": "The answer is a detailed and specific description of the quasicrystalline structure, which can be used as the correct option in a multiple-choice question. The question can be rephrased to ask for the best description from given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A structure with perfect translational symmetry but lacking rotational symmetry", "B": "A structure that can be fully described by conventional unit cells with long-range periodicity", "C": "A structure with 5-fold symmetry that can be constructed using two types of rhombuses following specific matching rules", "D": "A disordered structure with complete absence of both translational and rotational symmetry" }, "correct_answer": "C", "explanation": "The correct answer is C because quasicrystalline structures are characterized by ordered but non-periodic arrangements, often exhibiting forbidden rotational symmetries like 5-fold. The two-rhombus tiling method is a valid approach for modeling such structures. Option A is incorrect as it describes the opposite of quasicrystals (which have rotational but lack perfect translational symmetry). Option B is a common misconception applying conventional crystal thinking to quasicrystals. Option D incorrectly equates quasicrystals with amorphous materials, missing their deterministic ordering principles.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4585, "question": "What is one function that a transistor may perform in an electronic circuit?", "answer": "In an electronic circuit, a transistor may be used to amplify an electrical signal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释晶体管在电子电路中的功能，答案是一个简短的文字解释，没有提供选项或需要计算。 | 知识层次: 题目考查晶体管在电子电路中的基本功能，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别晶体管的基本功能之一（信号放大），属于最基础的定义性知识。题目不涉及概念解释或复杂体系，仅需简单回忆即可作答，因此属于等级1难度。", "convertible": true, "correct_option": "Amplify an electrical signal", "choice_question": "What is one function that a transistor may perform in an electronic circuit?", "conversion_reason": "The answer is a standard function of a transistor, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Amplify an electrical signal", "B": "Convert thermal energy directly into electrical energy", "C": "Store charge like a capacitor", "D": "Generate light through electroluminescence" }, "correct_answer": "A", "explanation": "The correct answer is A because transistors are fundamentally semiconductor devices designed to amplify or switch electronic signals. Option B exploits confusion with thermoelectric materials, which can convert thermal to electrical energy. Option C targets confusion with charge storage mechanisms in capacitors. Option D leverages the common association of semiconductors with light emission (LEDs), though standard transistors don't perform this function. These distractors were chosen because they represent plausible but incorrect material functionalities that an AI might associate with semiconductor devices.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2330, "question": "Both silver and aluminum have face-centered cubic lattices, and their atomic radii are very close, $r_{\\\\text{Ag}}=0.288\\\\mathrm{~nm}$ $r_{\\\\text{Al}}=0.286\\\\mathrm{nm}$, but they cannot form infinite solid solutions in the solid state. Explain the reason. (Northwestern Polytechnical University postgraduate entrance exam question)", "answer": "For substitutional solid solutions, the solute and solvent having the same crystal structure type and similar atomic radii are necessary conditions for forming infinite solid solutions. However, the $15\\\\%$ rule indicates that when $|\\\\delta|>15\\\\%$, the solid solubility (mole fraction) becomes very small, showing that when the size factor is within a favorable range for forming infinite solid solutions, its importance becomes secondary, meaning the extent of solid solubility depends on other factors. Here, the valence factor is crucial. Because the valence of $\\\\text{Ag}$ is 1, while that of Al is 3, i.e., the solid solubility of a high-valence element as a solute in a low-valence element is greater than that of a low-valence element in a high-valence element. Therefore, silver and aluminum cannot form infinite solid solutions in the solid state.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释银和铝不能形成无限固溶体的原因，需要文字解释和论述，答案也提供了详细的论述和理论依据，符合简答题的特征。 | 知识层次: 题目不仅需要理解面心立方晶格和原子半径对固溶体形成的影响，还需要分析价态因素对固溶度的作用机制。解答过程涉及多个概念的关联和综合分析，包括15%规则、价态效应等，需要较深入的推理和解释。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Because the valence of Ag is 1, while that of Al is 3, i.e., the solid solubility of a high-valence element as a solute in a low-valence element is greater than that of a low-valence element in a high-valence element.", "choice_question": "Both silver and aluminum have face-centered cubic lattices, and their atomic radii are very close, $r_{\\text{Ag}}=0.288\\mathrm{~nm}$ $r_{\\text{Al}}=0.286\\mathrm{nm}$, but they cannot form infinite solid solutions in the solid state. What is the main reason for this?", "conversion_reason": "The answer is a standard explanation involving valence differences, which can be presented as a correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because the valence of Ag is 1, while that of Al is 3, i.e., the solid solubility of a high-valence element as a solute in a low-valence element is greater than that of a low-valence element in a high-valence element.", "B": "Because their electronegativity difference (Δχ=0.28) exceeds the 0.1-0.2 range required for extensive solid solubility.", "C": "Because the stacking fault energies of Ag (16 mJ/m²) and Al (166 mJ/m²) differ by an order of magnitude, preventing coherent lattice matching.", "D": "Because the thermal expansion coefficients of Ag (18.9×10⁻⁶/K) and Al (23.1×10⁻⁶/K) create significant mismatch at elevated temperatures." }, "correct_answer": "A", "explanation": "The correct answer is A because the Hume-Rothery rules specifically state that large differences in valence (especially when a higher-valence element is the solvent) severely limit solid solubility. Option B is a strong distractor because electronegativity differences do affect solubility, but the given Δχ=0.28 is actually within acceptable limits (the threshold is typically ~0.4). Option C exploits the AI's potential confusion between stacking fault energy and lattice matching - while these values are real, stacking fault energy doesn't directly govern solubility. Option D uses real thermal expansion data but misapplies the concept, as thermal expansion mismatch affects thermal stress rather than solid solubility limits.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2637, "question": "The chemical behavior of S sometimes resembles that of a hexavalent element, while other times it resembles a tetravalent element. Please explain the reason for this behavior of S.", "answer": "The outermost electrons of S are 3s²3p⁴. When S combines with H to form H₂S, it accepts 2 electrons, and since S has 6 valence electrons in its outer shell, it behaves as a hexavalent element. When S combines with O to form SO₂, it provides 4 electrons, thus behaving as a tetravalent element.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释硫元素化学行为的原因，需要文字解释和论述，答案也是以文字形式详细说明了硫元素在不同化合物中的价态表现，符合简答题的特征。 | 知识层次: 题目要求解释硫元素在不同化合物中表现出不同化合价的原因，涉及对硫原子电子排布的理解以及在不同化学反应中电子行为的分析。这需要将基础概念（如电子排布、化合价）与实际化学反应相结合，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解硫元素的外层电子构型（3s²3p⁴）及其在不同化合物中的行为变化。题目要求考生能够分析硫在形成H₂S和SO₂时的电子行为差异，并解释其表现为六价和四价元素的原因。这涉及对价电子概念的掌握以及在不同化学环境中的应用，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "The outermost electrons of S are 3s²3p⁴. When S combines with H to form H₂S, it accepts 2 electrons, and since S has 6 valence electrons in its outer shell, it behaves as a hexavalent element. When S combines with O to form SO₂, it provides 4 electrons, thus behaving as a tetravalent element.", "choice_question": "The chemical behavior of S sometimes resembles that of a hexavalent element, while other times it resembles a tetravalent element. Which of the following explains the reason for this behavior of S?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The outermost electron configuration of S allows variable electron sharing, exhibiting both hexavalent and tetravalent characteristics depending on the electronegativity of bonding partners", "B": "Sulfur exhibits d-orbital hybridization in certain compounds, enabling expansion of its valence shell beyond the octet rule", "C": "The atomic radius of S changes significantly when forming different compounds, altering its effective valence state", "D": "Sulfur's 3p orbitals can undergo sp³ hybridization, creating four equivalent orbitals that sometimes share all electrons and sometimes only two" }, "correct_answer": "A", "explanation": "The correct answer is A because sulfur's 3s²3p⁴ configuration allows it to either gain 2 electrons (hexavalent behavior) or share 4 electrons (tetravalent behavior) depending on the electronegativity difference with bonding partners. Option B is a common misconception - while d-orbitals are sometimes invoked, the primary behavior stems from p-orbital electrons. Option C exploits the intuitive but incorrect link between atomic size and valence. Option D contains partially correct hybridization concepts but misapplies them to valence behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2313, "question": "If unidirectional continuous fibers are unevenly distributed but all well-aligned in parallel, will it affect the elastic modulus? Please explain.", "answer": "No effect. The modulus of the composite material $\\\\boldsymbol{E}_{\\\\mathrm{{L}}}=\\\\varphi_{\\\\mathrm{{f}}}\\\\boldsymbol{E}_{\\\\mathrm{{f}}}+\\\\varphi_{\\\\mathrm{{m}}}\\\\boldsymbol{E}_{\\\\mathrm{{m}}}$ varies linearly with the fiber volume percentage. Areas with dense fiber arrangement have a higher elastic modulus, while areas with sparse fiber arrangement have a lower elastic modulus. However, the linear relationship is additive, and the overall average modulus still equals the elastic modulus of a composite material with uniformly arranged fibers of the same volume fraction, meaning there is no effect.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释不均匀分布但平行排列的单向连续纤维是否会影响弹性模量，答案提供了详细的文字解释和论述，没有涉及选择题、判断题或计算题的特征。 | 知识层次: 题目涉及复合材料弹性模量的计算和分布不均匀性的影响分析，需要理解弹性模量与纤维体积分数的线性关系，并能综合分析不同分布情况下的平均模量。虽然公式直接给出，但需要解释不均匀分布对整体模量的影响，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解复合材料弹性模量的计算公式，并能够分析纤维分布不均匀但对整体模量的影响。题目涉及多步计算和概念关联，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "No effect. The modulus of the composite material $\\boldsymbol{E}_{\\mathrm{{L}}}=\\varphi_{\\mathrm{{f}}}\\boldsymbol{E}_{\\mathrm{{f}}}+\\varphi_{\\mathrm{{m}}}\\boldsymbol{E}_{\\mathrm{{m}}}$ varies linearly with the fiber volume percentage. Areas with dense fiber arrangement have a higher elastic modulus, while areas with sparse fiber arrangement have a lower elastic modulus. However, the linear relationship is additive, and the overall average modulus still equals the elastic modulus of a composite material with uniformly arranged fibers of the same volume fraction, meaning there is no effect.", "choice_question": "If unidirectional continuous fibers are unevenly distributed but all well-aligned in parallel, will it affect the elastic modulus?", "conversion_reason": "The answer is a clear and concise explanation that can be directly used as a correct option in a multiple-choice question. The question itself is already in a form that can be easily converted to a multiple-choice format by adding options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No effect, as the average modulus follows the rule of mixtures regardless of local fiber distribution", "B": "Yes, it decreases modulus due to stress concentration effects in sparsely distributed regions", "C": "Yes, it increases modulus because densely packed fibers create synergistic reinforcement", "D": "Only affects transverse modulus but not longitudinal modulus" }, "correct_answer": "A", "explanation": "The correct answer is A because the rule of mixtures (E_L = φ_fE_f + φ_mE_m) applies to the overall average modulus when fibers are parallel, regardless of local distribution variations. Option B exploits the common misconception that stress concentrations affect elastic modulus (they actually affect strength). Option C uses the appealing but incorrect concept of 'synergistic effects' in fiber packing. Option D creates confusion by mixing valid transverse modulus considerations with the longitudinal case.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4395, "question": "Is it possible to produce malleable cast iron in pieces having large cross-sectional dimensions? Why or why not?", "answer": "It is not possible to produce malleable iron in pieces having large cross-sectional dimensions. White cast iron is the precursor of malleable iron, and a rapid cooling rate is necessary for the formation of white iron, which may not be accomplished at interior regions of thick cross-sections.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么不能生产大截面尺寸的可锻铸铁，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目不仅需要理解可锻铸铁的基本概念，还需要分析其生产过程中的冷却速率对材料性能的影响，以及截面尺寸对冷却速率的限制作用。这涉及到多个概念的关联和综合运用，以及对材料加工条件的深入理解。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "It is not possible to produce malleable iron in pieces having large cross-sectional dimensions. White cast iron is the precursor of malleable iron, and a rapid cooling rate is necessary for the formation of white iron, which may not be accomplished at interior regions of thick cross-sections.", "choice_question": "Is it possible to produce malleable cast iron in pieces having large cross-sectional dimensions?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because the required rapid cooling rate for white iron formation cannot be achieved in thick sections", "B": "Yes, by using specialized alloying elements that promote graphite formation throughout the cross-section", "C": "Yes, if the heat treatment time is extended proportionally to the section thickness", "D": "No, because malleable iron inherently has poor mechanical properties in large dimensions" }, "correct_answer": "A", "explanation": "The correct answer is A because malleable iron production requires white iron as a precursor, which needs rapid cooling that's impossible in thick sections. B is a cognitive bias trap - while alloying affects graphite formation, it doesn't solve the cooling rate issue. C is a professional intuition trap - heat treatment time doesn't compensate for cooling rate limitations. D is a misleading statement - the limitation isn't mechanical properties but production constraints.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2561, "question": "What are the basic characteristics of silicate structures?", "answer": "The basic characteristics of silicate structures include: (1) The fundamental structural unit of silicates is the [SiO4] tetrahedron, with silicon atoms located in the interstices of the oxygen tetrahedron; (2) Each oxygen can be shared by at most two [SiO4] tetrahedra; (3) [SiO4] tetrahedra can exist isolated in the structure or be interconnected by sharing vertices; (4) The Si-O-Si bond forms a bent line.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述硅酸盐结构的基本特征，答案提供了详细的文字描述和解释，符合简答题的特点。 | 知识层次: 题目考查对硅酸盐结构基本特征的记忆和理解，属于基础概念的记忆性知识，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生记忆并理解硅酸盐结构的基本特征，包括[SiO4]四面体的基本结构单元、氧原子的共享方式、四面体的连接方式以及Si-O-Si键的形状。虽然涉及多个知识点，但都属于基础概念的记忆和理解范畴，不需要复杂的分析或比较。因此，在选择题型内属于中等难度。", "convertible": true, "correct_option": "The fundamental structural unit of silicates is the [SiO4] tetrahedron, with silicon atoms located in the interstices of the oxygen tetrahedron; Each oxygen can be shared by at most two [SiO4] tetrahedra; [SiO4] tetrahedra can exist isolated in the structure or be interconnected by sharing vertices; The Si-O-Si bond forms a bent line.", "choice_question": "Which of the following describes the basic characteristics of silicate structures?", "conversion_reason": "The answer is a standard description of the characteristics of silicate structures, which can be converted into a multiple-choice question format by presenting the correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The fundamental structural unit is the [SiO4] tetrahedron with silicon at the center, oxygen sharing between tetrahedra is limited to two, and Si-O-Si bonds exhibit bent geometry", "B": "Silicate structures are primarily based on [SiO6] octahedra with edge-sharing configurations, leading to linear Si-O-Si bonds", "C": "All oxygen atoms in silicate structures must be shared between two tetrahedra, resulting in exclusively 3D network structures", "D": "Silicon atoms occupy the vertices of oxygen tetrahedra, with each oxygen shared by exactly three [SiO4] units" }, "correct_answer": "A", "explanation": "Correct answer A accurately describes the [SiO4] tetrahedron as fundamental unit, proper oxygen sharing limitation, and characteristic bent bonds. Option B falsely introduces octahedral coordination and linear bonds - a common confusion with other ceramic structures. Option C overgeneralizes by requiring all oxygen sharing, ignoring isolated and chain silicates. Option D inverts the Si/O positions and violates the oxygen sharing limit - exploiting common misconceptions about coordination geometry.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 41, "question": "According to the电价规则, when half of the tetrahedral interstitial sites are filled, what valency cations should be inserted into the interstitial sites, and provide an example to illustrate.", "answer": "The ratio of cation to anion valency should be 1:1, such as ZnS.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释电价规则并举例说明，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目需要理解电价规则并应用到具体情境中，涉及多步推理和概念关联，如确定填隙位置与离子价态的关系，并举例说明。 | 难度: 在选择题中属于中等难度，题目要求理解电价规则并能够应用该规则进行多步计算和概念关联。需要综合分析填充一半四面体间隙位时阳离子的价态选择，并给出具体实例（如ZnS）来说明。虽然涉及多个概念和步骤，但在选择题型中通过选项可以辅助判断，因此难度适中。", "convertible": true, "correct_option": "The ratio of cation to anion valency should be 1:1, such as ZnS.", "choice_question": "According to the电价规则, when half of the tetrahedral interstitial sites are filled, what valency cations should be inserted into the interstitial sites?", "conversion_reason": "The answer is a standard concept with a clear example, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ratio of cation to anion valency should be 1:1, such as ZnS", "B": "The cation valency should be half of the anion valency, such as TiO2", "C": "The cation valency should equal the anion valency divided by coordination number, such as Al2O3", "D": "The cation valency should match the anion valency, such as NaCl" }, "correct_answer": "A", "explanation": "The correct answer is A because when half of tetrahedral sites are filled, charge balance requires 1:1 valency ratio (e.g. Zn²⁺ in S²⁻ framework). B is a common misconception from octahedral site filling rules. C uses a plausible-looking but incorrect mathematical relationship. D is a trap for those who confuse interstitial filling with substitutional solid solutions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4553, "question": "A thick steel sheet of area 400 cm^{2} is exposed to air near the ocean. After a one-year period it was found to experience a weight loss of 375g due to corrosion. To what rate of corrosion, in both mpy and mm / \\mathrm{yr}, does this correspond?", "answer": "the corrosion rate is 1.2mm / \\mathrm{yr}. the corrosion rate is 46.7 \\mathrm{mpy}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解腐蚀速率，答案也是具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括单位转换和公式应用（如腐蚀速率的计算），并需要理解腐蚀速率的不同单位（mpy和mm/yr）之间的转换关系。虽然不涉及复杂的综合分析或推理，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解腐蚀速率的概念，并进行多步单位换算和计算。题目涉及面积、重量损失和时间的关系，需要将克转换为毫米/年和mpy（密耳每年），这要求考生掌握相关公式和单位转换技巧。虽然题目提供了所有必要信息，但计算过程较为复杂，需要综合应用多个知识点。", "convertible": true, "correct_option": "the corrosion rate is 1.2mm / \\mathrm{yr}. the corrosion rate is 46.7 \\mathrm{mpy}.", "choice_question": "A thick steel sheet of area 400 cm^{2} is exposed to air near the ocean. After a one-year period it was found to experience a weight loss of 375g due to corrosion. To what rate of corrosion, in both mpy and mm / \\mathrm{yr}, does this correspond?", "conversion_reason": "The calculation problem has a specific and correct answer, which can be presented as a choice in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.2 mm/yr (46.7 mpy)", "B": "0.94 mm/yr (37.0 mpy)", "C": "1.5 mm/yr (59.1 mpy)", "D": "0.75 mm/yr (29.5 mpy)" }, "correct_answer": "A", "explanation": "The correct answer is A (1.2 mm/yr, 46.7 mpy) calculated using the weight loss, time, area, and density of steel. Option B (0.94 mm/yr) is designed to trap those who incorrectly use cm^3 instead of mm^3 in the mpy calculation. Option C (1.5 mm/yr) exploits the common mistake of using the wrong density value (8000 kg/m^3 instead of 7870 kg/m^3). Option D (0.75 mm/yr) is based on an incorrect area conversion (using 0.04 m^2 instead of 0.04 m^2). These distractors target common unit conversion errors and material property misconceptions in corrosion rate calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1349, "question": "A stress of 70MPa is applied in the [001] direction of an FCC crystal. Which slip system in the crystal will activate first?", "answer": "The resolved shear stress on the (111)[10-1] slip system is 28.58MPa, while the (1-11)[110] slip system does not slip. Therefore, the (111)[10-1] slip system activates first.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要计算不同滑移系上的分切应力，通过数值比较确定哪个滑移系先启动。答案中给出了具体的计算数值和比较过程，符合计算题的特征。 | 知识层次: 题目需要应用Schmid定律计算分解剪切应力，涉及多步计算和概念关联，但不需要复杂的综合分析或推理。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生计算不同滑移系的分切应力，并比较计算结果以确定哪个滑移系会首先激活。这涉及到晶体学方向、滑移系的选择、分切应力公式的应用等多个步骤的计算和概念理解。虽然题目提供了正确选项，但考生仍需具备综合分析能力才能正确解答。", "convertible": true, "correct_option": "(111)[10-1] slip system", "choice_question": "A stress of 70MPa is applied in the [001] direction of an FCC crystal. Which slip system in the crystal will activate first?", "conversion_reason": "The answer is a specific slip system, which can be presented as a clear option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(111)[10-1] slip system", "B": "(111)[1-10] slip system", "C": "(110)[1-11] slip system", "D": "(100)[011] slip system" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC crystals under [001] loading, the (111)[10-1] slip system has the highest Schmid factor (0.408) among all possible slip systems. Option B is a common misconception where the slip direction seems symmetric but actually has a lower Schmid factor (0.272). Option C is a trap using a plausible but non-FCC slip plane (110). Option D exploits the misconception that primary slip systems might involve low-index planes like (100), which don't exist in FCC crystals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4334, "question": "Consider 2.5 kg of austenite containing 0.65 wt % C, cooled to below 727 C (1341 F). How many kilograms each of pearlite and the proeutectoid phase form?", "answer": "the pearlite formed is 2.12 kg, and the proeutectoid ferrite formed is 0.38 kg.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算，应用材料科学中的相变知识，通过公式和计算得出具体的重量结果（2.12 kg和0.38 kg）。答案的形式是具体的数值，而不是选择、判断或文字解释。 | 知识层次: 题目涉及多步计算和概念关联，需要理解相图、杠杆定律的应用，并进行综合分析以确定各相的比例和重量。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及多步计算和概念关联，如理解奥氏体冷却过程中的相变、计算珠光体和先共析相的比例等。虽然题目给出了正确选项，但学生仍需掌握相关概念和计算方法才能正确选择。", "convertible": true, "correct_option": "the pearlite formed is 2.12 kg, and the proeutectoid ferrite formed is 0.38 kg", "choice_question": "Consider 2.5 kg of austenite containing 0.65 wt % C, cooled to below 727 C (1341 F). What are the kilograms each of pearlite and the proeutectoid phase formed?", "conversion_reason": "The answer is a specific and deterministic result, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pearlite: 2.12 kg, Proeutectoid ferrite: 0.38 kg", "B": "Pearlite: 2.30 kg, Proeutectoid cementite: 0.20 kg", "C": "Pearlite: 1.95 kg, Proeutectoid ferrite: 0.55 kg", "D": "Pearlite: 2.25 kg, Proeutectoid cementite: 0.25 kg" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately applies the lever rule to the eutectoid composition (0.77 wt% C) and the given composition (0.65 wt% C). Option B incorrectly identifies the proeutectoid phase as cementite, which forms only when the carbon content exceeds 0.77 wt%. Option C underestimates pearlite formation due to incorrect lever rule application. Option D makes the same error as B but with closer numerical values, exploiting the common misconception about proeutectoid phase identity near the eutectoid point.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4690, "question": "For some hypothetical metal, the equilibrium number of vacancies at 900^{\\circ} C is 2.3 × 10^{25} m^{-3}. If the density and atomic weight of this metal are 7.40g / {cm}^{3} and 85.5g / mol, respectively, calculate the fraction of vacancies for this metal at 900^{\\circ} C.", "answer": "the fraction of vacancies for this metal at 900^{\\circ} C is 4.41 × 10^{-4}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解空缺分数，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括密度和原子量的转换、原子密度的计算以及最终的空位分数计算。这需要理解空位形成的概念，并能将多个知识点（如密度、原子量、阿伏伽德罗常数）关联起来进行综合分析。虽然不涉及复杂的推理或创新设计，但计算过程较为复杂，超出了简单应用的范畴。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及计算金属中的空位分数，需要掌握密度、原子量和阿伏伽德罗常数等基本概念，并进行多步计算。虽然题目提供了必要的参数，但解题过程需要综合运用这些概念和公式，属于综合性计算问题。", "convertible": true, "correct_option": "4.41 × 10^{-4}", "choice_question": "For some hypothetical metal, the equilibrium number of vacancies at 900^{\\circ} C is 2.3 × 10^{25} m^{-3}. If the density and atomic weight of this metal are 7.40g / {cm}^{3} and 85.5g / mol, respectively, the fraction of vacancies for this metal at 900^{\\circ} C is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.41 × 10^{-4}", "B": "2.3 × 10^{-25}", "C": "1.8 × 10^{-3}", "D": "6.02 × 10^{23}" }, "correct_answer": "A", "explanation": "The correct answer is calculated by first determining the total number of atomic sites per cubic meter. Using the given density (7.40 g/cm³ = 7400 kg/m³) and atomic weight (85.5 g/mol), the number of atoms per cubic meter is (7400 × 6.022×10²³) / 85.5 ≈ 5.21×10²⁸ m⁻³. The vacancy fraction is then (2.3×10²⁵) / (5.21×10²⁸) ≈ 4.41×10⁻⁴. Option B is the raw vacancy concentration without normalization, exploiting the AI's potential to overlook unit conversion. Option C is a common error from misapplying the Boltzmann factor. Option D is Avogadro's number, a distracter for AI systems that might confuse fundamental constants with calculated values.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1135, "question": "According to the phase rule, what is the maximum number of equilibrium phases in a ternary system?", "answer": "4", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据相律回答三元系统中最大平衡相数，需要理解并应用相律知识进行简要回答，答案是一个具体的数值而非选择或判断。 | 知识层次: 题目考查对相律这一基本原理的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对相律基础定义的记忆，无需解释或分析，属于最基础的定义简答类型。", "convertible": true, "correct_option": "4", "choice_question": "According to the phase rule, what is the maximum number of equilibrium phases in a ternary system?", "conversion_reason": "The answer is a specific number, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "选项D", "C": "4", "D": "选项B" }, "correct_answer": "C", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 2558, "question": "If tension is applied along the [2 3] direction of an aluminum single crystal, determine the double slip system.", "answer": "The double slip system is (111)[0 1]－( 1)[101].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求确定双滑移系统，答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求确定双滑移系统，需要理解晶体滑移的基本原理，并能够将施加的张力方向与滑移系统关联起来。这涉及到多步分析和概念关联，但不需要复杂的推理或创新应用。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目要求确定双滑移系统，这需要理解晶体学方向、滑移面和滑移方向的概念。其次，题目中给出了特定的张力方向[2 3]，这需要考生能够正确计算和确定可能的滑移系统。最后，正确选项涉及两个滑移系统的组合，这需要考生能够综合分析并选择正确的组合。因此，该题目在选择题型中属于多角度分析论述的难度等级。", "convertible": true, "correct_option": "(111)[0 1]－( 1)[101]", "choice_question": "If tension is applied along the [2 3] direction of an aluminum single crystal, which of the following is the double slip system?", "conversion_reason": "The answer is a standard terminology in materials science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(111)[0 1]－( 1)[101]", "B": "(111)[1 0]－(111)[0 1]", "C": "(110)[1 1]－(101)[1 1]", "D": "(111)[1 0]－( 1)[0 1]" }, "correct_answer": "A", "explanation": "The correct answer A represents the primary and secondary slip systems activated under tension along [2 3] direction in FCC aluminum. Option B uses plausible slip planes but incorrect Burgers vectors. Option C mimics common BCC slip systems to exploit crystal structure confusion. Option D reverses the correct slip directions to create a mirror-image trap that may fool pattern-matching AIs.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2005, "question": "What is the relationship between the atomic arrangement and bonding in ordered alloys?", "answer": "This arrangement is related to the bonding energy (bond) between atoms. The greater the bonding energy, the less likely the atoms are to combine. If the bonding energy between dissimilar atoms is less than that between similar atoms, i.e., E_{A B}<(E_{A A}+E_{B B})/2, then the solute atoms will exhibit partially ordered or completely ordered arrangements.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释原子排列与键合之间的关系，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目涉及原子排列与键能关系的分析，需要理解键能对原子排列顺序的影响，并进行简单的比较和判断（E_{A B}<(E_{A A}+E_{B B})/2）。这属于中等应用层次，需要将基本概念与实际情况关联，并进行一定的综合分析。 | 难度: 在选择题型中，该题目需要考生理解原子排列与键能之间的复杂关系，并进行多步计算和概念关联。题目不仅要求掌握键能的基本概念，还需要综合分析不同原子间键能的比较（E_{AB}与(E_{AA}+E_{BB})/2的关系），从而推导出溶质原子的排列方式（部分有序或完全有序）。这种需要多角度分析和论述的题目，在选择题型中属于较高难度。", "convertible": true, "correct_option": "This arrangement is related to the bonding energy (bond) between atoms. The greater the bonding energy, the less likely the atoms are to combine. If the bonding energy between dissimilar atoms is less than that between similar atoms, i.e., E_{A B}<(E_{A A}+E_{B B})/2, then the solute atoms will exhibit partially ordered or completely ordered arrangements.", "choice_question": "What is the relationship between the atomic arrangement and bonding in ordered alloys?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The atomic arrangement is determined by the ratio of covalent to metallic bond character, with higher covalent character leading to more ordered structures", "B": "Ordered arrangements occur when the enthalpy of mixing is positive, favoring solute-solvent interactions over like-atom interactions", "C": "The greater the bonding energy between dissimilar atoms, the more likely they are to form disordered solid solutions", "D": "Atomic ordering requires the solute atoms to have larger radii than the solvent atoms to create lattice strain fields" }, "correct_answer": "A", "explanation": "Correct answer A identifies the crucial role of bond type in determining atomic order. The covalent-metallic character ratio directly affects directional bonding requirements. Option B reverses the thermodynamic condition (should be negative enthalpy). Option C inverts the bonding energy relationship (higher dissimilar bonding promotes order). Option D introduces an irrelevant size factor that doesn't fundamentally determine ordering.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1750, "question": "Most solid-phase reactions are in a. chemical reaction kinetics range b. diffusion kinetics range c. transition range", "answer": "b", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的三个选项中选择一个正确答案，符合选择题的特征 | 知识层次: 题目考查对固相反应动力学范围的基础概念记忆，属于基本原理的记忆性知识 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需直接回忆\"大多数固相反应属于扩散动力学范围\"这一知识点即可作答，无需复杂辨析或深度理解。题目选项设计简单明确，正确选项与其他选项区分度高，属于最简单的概念识别类型。", "convertible": true, "correct_option": "b. diffusion kinetics range", "choice_question": "Most solid-phase reactions are in", "conversion_reason": "原题目已经是单选题格式，可以直接转换。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The reaction rate is controlled by the slowest diffusing species", "B": "The reaction rate is determined by the activation energy of chemical bonds", "C": "The reaction occurs at the interface between two phases", "D": "The reaction rate follows Arrhenius temperature dependence" }, "correct_answer": "A", "explanation": "The correct answer is A because solid-phase reactions are typically diffusion-controlled due to the limited mobility of atoms in solids. Option B is a chemical kinetics trap that seems plausible but ignores the dominant diffusion mechanism. Option C is a partial truth trap that describes where reactions occur but not their rate control. Option D is a universal truth trap that applies to both diffusion and chemical kinetics, making it insufficient for distinguishing the controlling mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1706, "question": "What effect does activation energy have on the sensitivity of diffusion rate to temperature changes?", "answer": "The higher the activation energy, the greater the sensitivity of the diffusion rate to temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对激活能对扩散速率敏感性的影响进行文字解释和论述，答案是一个简短的论述性回答，而非选择、判断或计算。 | 知识层次: 题目要求理解活化能对扩散速率温度敏感性的影响，需要将活化能的概念与扩散速率的变化关联起来，并进行综合分析。虽然不涉及复杂计算，但需要一定的概念关联和推理分析能力。 | 难度: 在选择题中属于中等难度，需要理解激活能的概念及其对扩散速率的影响，同时需要综合分析温度变化对扩散速率敏感性的作用。虽然题目涉及多步计算和概念关联，但在选择题型中，通过选项的提示可以降低一定的分析难度。", "convertible": true, "correct_option": "The higher the activation energy, the greater the sensitivity of the diffusion rate to temperature.", "choice_question": "What effect does activation energy have on the sensitivity of diffusion rate to temperature changes?", "conversion_reason": "The answer is a standard statement that can be presented as one of the options in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The higher the activation energy, the greater the sensitivity of the diffusion rate to temperature", "B": "The lower the activation energy, the greater the sensitivity of the diffusion rate to temperature", "C": "Activation energy has no effect on the temperature sensitivity of diffusion rate", "D": "Only the pre-exponential factor determines the temperature sensitivity of diffusion rate" }, "correct_answer": "A", "explanation": "The correct answer is A because the Arrhenius equation shows diffusion rate depends exponentially on (-Ea/RT), making higher activation energy systems more temperature-sensitive. Option B reverses this relationship, exploiting the common misconception that lower barriers imply greater sensitivity. Option C is a complete negation trap, appealing to those who overlook the fundamental role of activation energy. Option D targets those who focus solely on the pre-exponential factor while ignoring the exponential term's temperature dependence.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2835, "question": "For a pre-annealed metal polycrystal, the true stress-strain curve in the plastic region can be approximately expressed as ∇σ_T= kε_T^n, where k and n are empirical constants, referred to as the strength coefficient and strain hardening exponent, respectively. If there are two materials, A and B, with roughly equal k values, but n_A=0.5 and n_B=0.2, which one has a higher dislocation density at the same plastic strain, and why?", "answer": "When ε_T<1, if 015%). Option A is a valence electron trap - while electronegativity is similar, this alone doesn't guarantee solubility. Option C exploits crystal structure similarity bias, ignoring size mismatch. Option D uses a real but irrelevant factor (Zn's higher VEC doesn't directly affect solubility in this context).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1017, "question": "What is the physical meaning of diffusion activation energy?", "answer": "The physical meaning of diffusion activation energy is the energy barrier that must be overcome during atomic jumps, which is the obstruction posed by surrounding atoms.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释扩散激活能的物理意义，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查扩散激活能的基本概念和物理意义的记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目属于概念解释和描述难度。题目要求理解扩散激活能的物理意义，即原子跳跃过程中必须克服的能量障碍，这需要一定的概念理解而非简单记忆定义。虽然不涉及复杂概念体系，但比基本定义简答要求更高的理解深度。", "convertible": true, "correct_option": "The energy barrier that must be overcome during atomic jumps, which is the obstruction posed by surrounding atoms.", "choice_question": "What is the physical meaning of diffusion activation energy?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The energy barrier that must be overcome during atomic jumps, which is the obstruction posed by surrounding atoms", "B": "The total kinetic energy of diffusing atoms when they reach the melting point of the material", "C": "The energy difference between the vacancy formation energy and the atomic jump energy", "D": "The minimum energy required to break all atomic bonds in the diffusion path simultaneously" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines diffusion activation energy as the energy barrier for atomic jumps. Option B exploits the common misconception that diffusion is solely temperature-dependent. Option C combines two related but distinct concepts (vacancy formation and jump energy) to create a plausible-sounding but incorrect definition. Option D exaggerates the energy requirement by suggesting complete bond breaking, which is not necessary for diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3154, "question": "In stable ZrO2 material, cations form an fcc structure, and anions occupy tetrahedral interstitial sites. If 20 mol% CaO is added, calculate the percentage of occupied tetrahedral interstitial sites.", "answer": "Zr4+ and Ca2+ cations occupy the face-centered cubic lattice sites. 100 cations can form 25 unit cells, with a total of 25×8=200 tetrahedral interstitial sites. Therefore, the percentage of occupied tetrahedral interstitial sites is 180÷200=90%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算占据的四面体间隙位置的百分比），并且答案给出了具体的计算步骤和结果。这符合计算题的特征，即需要应用公式和进行数值推导。 | 知识层次: 题目需要进行多步计算（包括单位晶胞的计算、间隙位置的计算和百分比计算），并需要理解阳离子和阴离子在ZrO2结构中的位置关系以及掺杂CaO对间隙位置的影响。虽然不涉及复杂的机理分析或创新设计，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念并进行多步计算。题目涉及晶体结构、间隙位置占据率的计算，以及掺杂对结构的影响。虽然正确选项提供了计算步骤，但需要考生具备扎实的晶体学基础和计算能力，能够正确理解并应用给定的信息。", "convertible": true, "correct_option": "90%", "choice_question": "In stable ZrO2 material, cations form an fcc structure, and anions occupy tetrahedral interstitial sites. If 20 mol% CaO is added, what is the percentage of occupied tetrahedral interstitial sites?", "conversion_reason": "The answer to the calculation question is a specific numerical value (90%), which can be directly used as the correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice format by asking for the percentage directly.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "90%", "B": "80%", "C": "70%", "D": "60%" }, "correct_answer": "A", "explanation": "In ZrO2 with fcc cation arrangement, there are 8 tetrahedral sites per unit cell. Each CaO substitution creates one oxygen vacancy, so 20% CaO doping means 20% of oxygen sites are vacant. Since anions initially occupy all tetrahedral sites, the new occupancy is 100% - 10% (20% of 50% anion sites) = 90%. Option B is a common calculation error from directly subtracting 20%. Option C results from misapplying vacancy distribution. Option D arises from incorrect site counting in the fcc structure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3156, "question": "It is known that polyethylene belongs to the body-centered orthorhombic structure, with lattice constants a=0.740nm, b=0.493nm, c=0.253nm, and two molecular chains passing through a unit cell. Calculate the density ρc of fully crystalline polyethylene.", "answer": "Polyethylene (C2H4) is produced through addition polymerization, with its repeating unit being CH2-CH2. Considering one repeating unit as a lattice point, it can be determined that each unit cell contains two repeating units. Therefore, the density ρc of fully crystalline polyethylene can be calculated as ρc = 2(12×2 + 1×4) / (6.023×10^23) / (0.740×0.493×0.253)×10^-21 ≈ 1.01 g/cm³.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解聚乙烯的密度，答案给出了具体的计算过程和结果。 | 知识层次: 题目需要进行多步计算，包括分子量的计算、单位晶胞体积的计算以及密度的计算，同时需要理解晶格常数和单位晶胞的概念，并能够将这些概念和公式结合起来进行综合分析。虽然不涉及复杂的推理分析或创新应用，但已经超出了简单应用的范围。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、密度计算、化学式推导等多个概念，并进行多步骤的综合计算。虽然题目提供了部分参数，但需要考生自行推导化学式、计算分子量、理解单位晶胞概念，并正确应用密度公式进行计算。这些步骤在选择题型中属于较为复杂的综合分析过程。", "convertible": true, "correct_option": "1.01 g/cm³", "choice_question": "It is known that polyethylene belongs to the body-centered orthorhombic structure, with lattice constants a=0.740nm, b=0.493nm, c=0.253nm, and two molecular chains passing through a unit cell. The density ρc of fully crystalline polyethylene is approximately:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.01 g/cm³", "B": "0.92 g/cm³", "C": "1.16 g/cm³", "D": "0.85 g/cm³" }, "correct_answer": "A", "explanation": "正确答案A通过精确计算得出：密度=(2×28.05g/mol)/(0.740×0.493×0.253×10⁻²¹cm³×6.022×10²³)=1.01g/cm³。干扰项B(0.92)是常见错误，因误用单链计算；C(1.16)源自错误假设面心立方堆积；D(0.85)则混淆了结晶区与无定形区的典型密度值。这些干扰项分别利用了单位晶胞理解偏差、晶体结构误判和材料状态混淆等认知陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 484, "question": "In the bainitic transformation, neither Fe nor C atoms undergo diffusion.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（In the bainitic transformation, neither Fe nor C atoms undergo diffusion），并要求判断其正确性（答案：√），这符合判断题的特征。 | 知识层次: 题目考查贝氏体转变过程中Fe和C原子扩散行为的基本概念记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆贝氏体转变过程中Fe和C原子的扩散行为即可作答，无需深入理解或分析复杂概念。", "convertible": true, "correct_option": "√", "choice_question": "In the bainitic transformation, neither Fe nor C atoms undergo diffusion.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All martensitic transformations in steels occur without any diffusion of carbon atoms.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most martensitic transformations in steels are diffusionless, in high-carbon steels some carbon diffusion may occur during the transformation. This statement uses the absolute term 'all' which makes it incorrect. The subtlety lies in the carbon content dependence of the transformation mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4774, "question": "A single crystal of zinc is oriented for a tensile test such that its slip plane normal makes an angle of 65 degrees with the tensile axis. The most favored slip direction makes an angle of 30 degrees with the same tensile axis. If plastic deformation begins at a tensile stress of 2.5 MPa (355 psi), determine the critical resolved shear stress for zinc.", "answer": "the critical resolved shear stress for zinc is 0.91 mpa (130 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用（临界分切应力公式）来求解临界分切应力，答案是一个具体的数值计算结果。 | 知识层次: 题目需要应用临界分切应力公式进行计算，涉及角度转换和应力分解，属于多步计算和概念关联的中等应用层次。虽然不涉及复杂的综合分析或机理解释，但需要理解滑移面和滑移方向的概念，并进行正确的公式应用和数值计算。 | 难度: 在选择题中属于中等偏上难度，需要理解临界分切应力的概念，掌握施密特定律的计算方法，并进行多步骤的三角函数计算。虽然题目提供了所有必要参数，但需要考生正确关联角度参数与应力分量之间的关系，属于综合性计算问题。", "convertible": true, "correct_option": "0.91 MPa (130 psi)", "choice_question": "A single crystal of zinc is oriented for a tensile test such that its slip plane normal makes an angle of 65 degrees with the tensile axis. The most favored slip direction makes an angle of 30 degrees with the same tensile axis. If plastic deformation begins at a tensile stress of 2.5 MPa (355 psi), what is the critical resolved shear stress for zinc?", "conversion_reason": "The calculation problem has a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.91 MPa (130 psi)", "B": "1.25 MPa (180 psi)", "C": "2.17 MPa (315 psi)", "D": "3.54 MPa (510 psi)" }, "correct_answer": "A", "explanation": "正确答案A是通过正确应用临界分切应力公式τ=σ*cos(λ)*cos(φ)计算得出，其中σ=2.5 MPa, λ=30°, φ=65°。干扰项B是直接使用cos(30°)计算的结果，忽略了滑移面角度的影响。干扰项C错误地使用了sin函数而非cos函数计算。干扰项D是原始拉伸应力值，完全忽略了分切应力的概念。这些干扰项利用了材料科学中常见的三角函数误用和概念混淆策略。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4168, "question": "How many grams are there in one amu of a material?", "answer": "1.66 x 10^-24 g/amu", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算（1 amu转换为克），答案是一个具体的数值结果（1.66 x 10^-24 g/amu），属于典型的计算题特征。 | 知识层次: 题目仅涉及基本单位换算（amu到克）的直接计算，仅需套用已知的换算系数1.66 x 10^-24 g/amu，无需多步计算或概念关联，属于基础公式的直接应用。 | 难度: 在选择题型中，该题目仅涉及单一公式的直接应用（1 amu = 1.66 x 10^-24 g），无需任何额外的计算步骤或概念组合。学生只需记住或识别这一基本换算关系即可选择正确答案，属于最基础的难度等级。", "convertible": true, "correct_option": "1.66 x 10^-24 g/amu", "choice_question": "How many grams are there in one amu of a material?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.66 x 10^-24 g/amu", "B": "6.02 x 10^23 g/amu", "C": "1.00 g/amu", "D": "9.11 x 10^-28 g/amu" }, "correct_answer": "A", "explanation": "The correct answer is A because 1 amu is defined as 1/12 the mass of a carbon-12 atom, which equals 1.66 x 10^-24 grams. Option B is Avogadro's number, which is a common confusion between mass per atom and number of atoms per mole. Option C exploits the intuitive but incorrect assumption that 1 amu equals 1 gram. Option D is the mass of an electron, which is irrelevant but numerically similar to the correct answer, creating a unit confusion trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1122, "question": "If the carbon content is 0.8% in high-carbon steel with an initial grain size of 0.05mm, calculate the grain size and its growth value after holding at 870‰ for 1 hour. The formula D^(1/n) - D0^(1/n) = c t can be used for calculation, where at 870‰, the constant c is 2×10^(-8), n is 0.2, D and D0 are grain sizes in mm, and t is time in min.", "answer": "At 870‰ for 1h: D^(1/0.2) - D0^(1/0.2) = 2×10^(-8)×60; D^5 - D0^5 = 1.2×10^(-6); D^5 = 0.05^5 + 1.2×10^(-6) = 3.125×10^(-7) + 12×10^(-7) = 15.13×10^(-7); D = (15.13×10^(-7))^(1/5) mm = 0.069mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求使用给定的公式进行数值计算，以求解晶粒尺寸及其生长值。答案展示了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和公式应用，需要理解晶粒生长公式并正确代入数值进行计算，同时需要处理单位转换（小时到分钟）和指数运算。虽然计算过程较为直接，但涉及多个步骤和概念的综合应用，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，题目涉及多步骤计算和公式应用，需要考生理解晶粒生长公式并正确代入数值进行计算。虽然题目提供了公式和常数，但计算过程较为复杂，包括指数运算和单位转换，对考生的计算能力和细节处理能力有一定要求。", "convertible": true, "correct_option": "0.069mm", "choice_question": "If the carbon content is 0.8% in high-carbon steel with an initial grain size of 0.05mm, and it is held at 870‰ for 1 hour, what is the final grain size? Use the formula D^(1/n) - D0^(1/n) = c t, where at 870‰, the constant c is 2×10^(-8), n is 0.2, D and D0 are grain sizes in mm, and t is time in min.", "conversion_reason": "The calculation yields a specific numerical answer (0.069mm), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.069mm", "B": "0.052mm", "C": "0.082mm", "D": "0.061mm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.069mm) calculated using the given grain growth formula. Option B (0.052mm) exploits the cognitive bias of minimal change by suggesting negligible growth. Option C (0.082mm) is designed to trap those who might confuse the exponent n=0.2 with n=2. Option D (0.061mm) targets the common error of using seconds instead of minutes for the time variable t.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2739, "question": "If an extra (111) plane is embedded, causing a small-angle grain boundary tilted by 1° in α-Fe, calculate the average distance between the dislocations.", "answer": "The lattice constant of α-Fe crystal $$ \\\\alpha=\\\\frac{4r_{\\\\mathrm{Fe}}}{\\\\sqrt{3}}=\\\\frac{4\\\\times0.1241}{\\\\sqrt{3}}=0.2866(\\\\mathrm{nm})$$ $$x d_{111}={\\\\frac{a}{\\\\sqrt{{{1}}^{2}+{{1}}^{2}+{{1}}^{2}}}}={\\\\frac{0.2866}{\\\\sqrt{3}}}=0.16547({\\\\mathrm{nm}})$$ $$ \\\\sin{\\\\frac{\\\\theta}{2}}={\\\\frac{d_{\\\\mathrm{{111}}}}{\\\\it{l}}}$$ $$ \\\\begin{array}{r}{\\\\lambda=\\\\frac{d_{\\\\mathrm{{n1}}}}{\\\\sin\\\\frac{\\\\theta}{2}}=\\\\frac{0.16547}{\\\\sin\\\\left(\\\\frac{1}{2}\\\\right)^{\\\\circ}}=18.9615(\\\\mathrm{nm})}\\\\end{array}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案中包含了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要理解晶格常数、晶面间距以及小角度晶界的几何关系，并应用三角函数进行计算。虽然不涉及复杂的综合分析或创新应用，但需要一定的综合分析能力和对材料科学基础知识的理解。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、晶面间距计算、小角度晶界与位错的关系等多个概念，并进行多步骤的计算和综合分析。虽然题目提供了计算公式和步骤，但需要考生具备扎实的基础知识和一定的计算能力才能正确解答。", "convertible": true, "correct_option": "18.9615 nm", "choice_question": "If an extra (111) plane is embedded, causing a small-angle grain boundary tilted by 1° in α-Fe, what is the average distance between the dislocations?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "18.9615 nm", "B": "9.4807 nm", "C": "0.2774 nm", "D": "36.234 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (18.9615 nm) calculated using the Frank formula for small-angle grain boundaries: D = b/θ, where b is the Burgers vector (0.248 nm for α-Fe) and θ is the tilt angle in radians (1° = 0.01745 rad). B (9.4807 nm) is half the correct distance, exploiting the AI's tendency to divide by 2 when unsure. C (0.2774 nm) uses the lattice parameter instead of Burgers vector, targeting confusion between structural and defect parameters. D (36.234 nm) doubles the correct distance, testing if AI misapplies angle conversion factors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 933, "question": "6.Hardenability and hardening capacity", "answer": "Hardenability refers to the ability of an alloy to be quenched into martensite, mainly related to the critical cooling rate, with its magnitude represented by the depth of the hardened layer. Hardening capacity refers to the maximum hardness that can be achieved after quenching, primarily related to the carbon content of the steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对两个专业术语进行文字解释和论述，没有提供选项或要求计算，符合简答题的特征。 | 知识层次: 题目考查对\"Hardenability\"和\"Hardening capacity\"这两个基本概念的定义和区别的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个相关但不同的概念（Hardenability和Hardening capacity），但正确选项已经清晰地给出了两者的定义和主要区别。学生需要理解并区分这两个概念，但不需要进行复杂的分析或推导。这属于概念解释和描述的层次，比基本定义简答稍难，但比复杂概念体系阐述简单。", "convertible": true, "correct_option": "Hardenability refers to the ability of an alloy to be quenched into martensite, mainly related to the critical cooling rate, with its magnitude represented by the depth of the hardened layer. Hardening capacity refers to the maximum hardness that can be achieved after quenching, primarily related to the carbon content of the steel.", "choice_question": "Which of the following correctly describes hardenability and hardening capacity?", "conversion_reason": "The answer is a standard definition that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hardenability is determined by the critical cooling rate and reflected in the depth of martensite formation, while hardening capacity depends on carbon content and determines maximum achievable hardness", "B": "Hardenability refers to the maximum hardness achievable after quenching, while hardening capacity measures the depth of martensite formation during quenching", "C": "Both hardenability and hardening capacity are primarily determined by the carbon content of the steel", "D": "Hardenability depends on the alloy's thermal conductivity, while hardening capacity is controlled by the quenching medium's cooling rate" }, "correct_answer": "A", "explanation": "The correct answer A precisely distinguishes between hardenability (related to critical cooling rate and depth of hardening) and hardening capacity (related to carbon content and maximum hardness). Option B reverses the definitions, exploiting a common swapping error. Option C creates a false equivalence trap by suggesting both properties depend on carbon content. Option D introduces plausible-sounding but incorrect parameters (thermal conductivity and quenching medium), exploiting the AI's tendency to associate these factors with heat treatment processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4100, "question": "[b] The term \"composite\" applies to materials that feature polymeric materials only.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错，答案以F（False）给出，符合判断题的特征。 | 知识层次: 题目考查对复合材料定义的基础概念记忆和理解，仅需判断陈述是否符合基本定义，无需复杂分析或应用。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆复合材料的基本定义即可判断正误，无需深入理解或分析多个概念。", "convertible": true, "correct_option": "F", "choice_question": "[b] The term \"composite\" applies to materials that feature polymeric materials only.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect ionic bonding with no covalent character.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics are predominantly ionically bonded, most exhibit some degree of covalent character. The statement uses the absolute term 'all' which is incorrect. Even classic ionic ceramics like NaCl have about 5% covalent character due to electron sharing. Advanced ceramics like silicon carbide (SiC) are predominantly covalently bonded. This question tests understanding of bonding types in ceramics and the danger of absolute statements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3253, "question": "For an Fe-3% (Si) alloy containing MnS particles, when the particle radius is $0.05\\\\mu m$ and the volume fraction is approximately 1%, annealing below 850℃ results in the cessation of normal grain growth when the average grain diameter of the matrix is $6\\\\mu m$. Analyze the reason for this phenomenon.", "answer": "According to the formula for calculating the limiting average grain size: $$\\\\overline{{D}}_{\\\\mathrm{lim}}=\\\\frac{4r}{3\\\\varphi}=\\\\frac{4\\\\times0.05}{3\\\\times0.01}=6.7~\\\\mu\\\\mathrm{m}$$ The dispersed particles exert a pinning effect on grain boundary migration. When the driving force for grain boundary migration provided by grain boundary energy equals the resistance to grain boundary migration caused by the dispersed particles, the limiting grain size is reached. Further holding does not increase the grain size, as calculated by $\\\\overline{{D}}_{\\\\mathrm{lim}}=6.7~\\\\mu m$. During annealing, the average matrix diameter is 6 μm, which is already close to $\\\\overline{{D}}_{\\\\mathrm{lim}}$, so grain growth becomes extremely slow and nearly stops.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析现象的原因，答案提供了详细的文字解释和论述，包括公式应用和理论分析，符合简答题的特征。 | 知识层次: 题目需要综合运用材料科学中的晶粒生长理论、第二相粒子钉扎效应以及相关公式计算，进行推理分析和机理解释。涉及多步计算和概念关联，思维过程要求较高。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生综合运用材料科学中的晶粒生长理论、第二相粒子钉扎效应以及相关计算公式，进行复杂的推理分析和机理解释。具体来说，考生需要：", "convertible": true, "correct_option": "The dispersed particles exert a pinning effect on grain boundary migration, and when the driving force for grain boundary migration equals the resistance caused by the particles, the limiting grain size is reached.", "choice_question": "For an Fe-3% (Si) alloy containing MnS particles, when the particle radius is $0.05\\mu m$ and the volume fraction is approximately 1%, annealing below 850℃ results in the cessation of normal grain growth when the average grain diameter of the matrix is $6\\mu m$. What is the reason for this phenomenon?", "conversion_reason": "The answer is a standard explanation that can be converted into a correct option for a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the reason behind the phenomenon.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dispersed particles exert a pinning effect on grain boundary migration, and when the driving force for grain boundary migration equals the resistance caused by the particles, the limiting grain size is reached.", "B": "The MnS particles dissolve into the matrix at 850°C, altering the solute drag effect and stopping grain growth.", "C": "The critical grain size is determined by the ratio of particle spacing to grain boundary curvature, reaching equilibrium at 6μm.", "D": "The stacking fault energy of the Fe-Si matrix decreases below 850°C, inhibiting dislocation motion necessary for grain growth." }, "correct_answer": "A", "explanation": "The correct answer is A because the Zener pinning effect explains how second-phase particles can inhibit grain boundary migration when the driving force for grain growth is balanced by the particle drag force. Option B is incorrect because MnS particles do not dissolve at 850°C (melting point ~1620°C) and solute drag is not the primary mechanism here. Option C contains partially correct elements but misrepresents the fundamental relationship - it's the particle size/volume fraction ratio that determines the limiting grain size, not spacing/curvature. Option D introduces an irrelevant mechanism (stacking fault energy) that doesn't apply to normal grain growth processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 670, "question": "What is the difference in diffusion activation energy between interstitial atoms and substitutional atoms?", "answer": "The diffusion activation energy of interstitial atoms is much smaller than that of substitutional atoms.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述间隙原子和置换原子在扩散激活能上的差异，答案提供了文字解释而非选择、判断或计算。 | 知识层次: 题目考查对间隙原子和置换原子扩散激活能差异的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及扩散激活能的基本概念，但需要考生理解并比较两种不同原子（间隙原子和置换原子）的扩散激活能差异。这超出了简单的定义记忆，要求考生能够解释和描述相关概念的区别。然而，题目并未涉及复杂的推导或多步骤分析，因此难度等级为2。", "convertible": true, "correct_option": "The diffusion activation energy of interstitial atoms is much smaller than that of substitutional atoms.", "choice_question": "What is the difference in diffusion activation energy between interstitial atoms and substitutional atoms?", "conversion_reason": "The answer is a standard comparison that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diffusion activation energy of interstitial atoms is much smaller than that of substitutional atoms", "B": "The diffusion activation energy is identical for both mechanisms since both involve atomic jumps", "C": "Substitutional diffusion requires lower activation energy due to larger available lattice sites", "D": "Interstitial diffusion shows higher activation energy because it requires breaking more atomic bonds" }, "correct_answer": "A", "explanation": "The correct answer is A because interstitial atoms diffuse through smaller gaps in the crystal lattice, requiring less energy to move compared to substitutional atoms which need to overcome larger energy barriers as they exchange with lattice atoms. Option B is incorrect because it falsely assumes identical energy requirements despite different diffusion mechanisms. Option C reverses the correct relationship, exploiting the intuitive but incorrect assumption that larger sites would facilitate easier diffusion. Option D creates a plausible-sounding but incorrect bond-breaking argument that might trap models relying on surface-level chemical intuition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1281, "question": "The growth morphology of crystals is related to what distribution at the interface front?", "answer": "Temperature gradient", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释晶体生长形态与界面前沿分布的关系，答案需要文字解释而非选择、判断或计算 | 知识层次: 题目考查晶体生长形态与界面前沿温度梯度分布的关系，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即晶体生长形态与界面前沿温度梯度的关系。题目直接考察学生对基本定义的掌握，无需复杂推理或概念间的比较分析，属于最基础的知识点考察。", "convertible": true, "correct_option": "Temperature gradient", "choice_question": "The growth morphology of crystals is related to which of the following distributions at the interface front?", "conversion_reason": "The answer is a standard term (Temperature gradient) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Temperature gradient", "B": "Dislocation density distribution", "C": "Electron cloud polarization", "D": "Atomic mass gradient" }, "correct_answer": "A", "explanation": "The correct answer is A because crystal growth morphology is primarily determined by the temperature gradient at the interface front, which controls the rate of atomic attachment. Option B exploits the common misconception that dislocations directly determine growth shapes. Option C uses an advanced but irrelevant quantum mechanics concept to confuse systems familiar with electronic structure. Option D creates a false analogy with diffusion processes by suggesting mass gradients are decisive.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4149, "question": "In the visible spectrum, a thick metal specimen will be(a) Transparent(b) Translucent(c) Opaque", "answer": "In the visible spectrum, a thick metal specimen is opaque.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项(a)、(b)、(c)中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对金属在可见光谱中光学性质的基本概念记忆，属于基础概念的记忆和理解层面。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需识别金属在可见光谱中的基本特性（不透明性），无需复杂理解或辨析步骤。", "convertible": true, "correct_option": "Opaque", "choice_question": "In the visible spectrum, a thick metal specimen will be", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dislocation density decreases exponentially with annealing temperature", "B": "The yield strength increases linearly with grain size according to Hall-Petch relationship", "C": "The stacking fault energy is the primary factor determining creep resistance at high temperatures", "D": "The Burgers vector magnitude affects dislocation mobility but not the critical resolved shear stress" }, "correct_answer": "A", "explanation": "Correct answer is A because dislocation density typically follows an Arrhenius-type relationship with temperature during annealing. B is a Hall-Petch reversal trap - the relationship is inverse for nanocrystalline materials. C exploits creep mechanism confusion - stacking fault energy primarily affects cross-slip not diffusional creep. D uses partial truth - Burgers vector affects both mobility and CRSS through the line tension term.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 597, "question": "The necessary condition for forming an ordered solid solution is", "answer": "Slow cooling rate", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释形成有序固溶体的必要条件，需要文字解释和论述，而不是从选项中选择或简单判断对错。答案\"Slow cooling rate\"是一个简短的文字解释，符合简答题的特征。 | 知识层次: 题目考查形成有序固溶体的基本条件，属于基础概念的记忆和理解范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，涉及有序固溶体形成的必要条件这一简单定义。学生只需回忆\"慢冷速率\"这一关键知识点即可作答，无需进行概念解释或复杂分析，属于最基本的选择题难度等级。", "convertible": true, "correct_option": "Slow cooling rate", "choice_question": "What is the necessary condition for forming an ordered solid solution?", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by providing options including the correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slow cooling rate", "B": "High quenching temperature", "C": "Precise stoichiometric ratio", "D": "Large atomic size mismatch" }, "correct_answer": "A", "explanation": "Slow cooling rate allows sufficient time for atomic ordering, which is essential for forming an ordered solid solution. Option B exploits the common misconception that high temperature alone can induce ordering, while in reality rapid quenching would prevent ordering. Option C targets the confusion between ordered solid solutions and intermetallic compounds, where stoichiometry is critical. Option D leverages the intuitive but incorrect notion that size mismatch promotes ordering, when it actually favors disordered solutions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 324, "question": "Explain the meaning of interstitial phase", "answer": "Interstitial phase is an intermediate phase (size-factor compound), and the number of A and B atoms is proportional. The alloy components are all in interstitial positions, with very small sizes themselves. In terms of properties, it exhibits high hardness and poor plasticity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释间隙相的含义，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对间隙相（interstitial phase）这一基本概念的定义和特性的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生解释\"interstitial phase\"的定义和基本特性，属于概念解释和描述的难度级别。虽然涉及多个知识点（如定义、结构特点、性质），但不需要复杂的分析或比较，只需记忆和理解基本概念即可回答。因此属于中等难度（等级2）。", "convertible": true, "correct_option": "Interstitial phase is an intermediate phase (size-factor compound), and the number of A and B atoms is proportional. The alloy components are all in interstitial positions, with very small sizes themselves. In terms of properties, it exhibits high hardness and poor plasticity.", "choice_question": "Which of the following best describes the interstitial phase?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct description as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An intermediate phase where alloy components occupy interstitial sites with size constraints, exhibiting high hardness but poor plasticity", "B": "A solid solution phase where solute atoms randomly substitute for solvent atoms in the crystal lattice", "C": "A phase formed by interstitial atoms creating lattice distortions that enhance both strength and ductility", "D": "A metastable phase where interstitial atoms preferentially segregate to grain boundaries" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the interstitial phase as an intermediate phase with size-factor constraints, where components occupy interstitial positions leading to characteristic high hardness but poor plasticity. Option B incorrectly describes a substitutional solid solution. Option C is a trap combining correct strength enhancement with incorrect ductility improvement. Option D describes a grain boundary segregation phenomenon rather than the interstitial phase.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4876, "question": "What are the characteristics of continuous casting technique?", "answer": "For continuous casting, at the conclusion of the extraction process, the molten metal is cast into a continuous strand having either a rectangular or circular cross-section; these shapes are desirable for subsequent secondary metal-forming operations. The chemical composition and mechanical properties are relatively uniform throughout the cross-section.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释连续铸造技术的特点，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查连续铸造技术的基本特征，属于对基本原理和特点的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型内，该题目属于概念解释和描述难度等级。题目要求考生理解连续铸造技术的基本特征，包括铸造过程的描述和最终产品的形状与性质。虽然涉及多个知识点（如铸造过程、产品形状、机械性能等），但都属于基础概念记忆层次，不需要复杂的分析或比较。正确选项提供了清晰的解释，考生只需识别和匹配这些特征即可。", "convertible": true, "correct_option": "For continuous casting, at the conclusion of the extraction process, the molten metal is cast into a continuous strand having either a rectangular or circular cross-section; these shapes are desirable for subsequent secondary metal-forming operations. The chemical composition and mechanical properties are relatively uniform throughout the cross-section.", "choice_question": "Which of the following describes the characteristics of continuous casting technique?", "conversion_reason": "The answer is a standard description of the characteristics of continuous casting technique, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The process produces a continuous strand with uniform cross-section, ideal for secondary forming operations, with consistent chemical composition throughout.", "B": "The technique allows for rapid solidification rates, resulting in fine-grained microstructures similar to those achieved through powder metallurgy.", "C": "Continuous casting enables precise control over dendrite arm spacing, making it superior to ingot casting for producing single-crystal components.", "D": "This method significantly reduces porosity compared to traditional casting, achieving densities comparable to hot isostatic pressing." }, "correct_answer": "A", "explanation": "Option A correctly describes the key characteristics of continuous casting, including continuous strand production, uniform cross-section, and consistent composition. Option B is misleading by suggesting rapid solidification rates (actually slower than some methods) and incorrect microstructure comparison. Option C falsely claims single-crystal production capability (a common misconception). Option D exaggerates density achievements by comparing to HIP, a specialized process.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2906, "question": "Briefly describe the influencing factors of the glass transition temperature of polymers.", "answer": "There are many factors affecting the glass transition temperature, usually including (1) chain flexibility; (2) the influence of intermolecular forces; (3) the effect of copolymerization; (4) the influence of plasticizers, etc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述聚合物玻璃化转变温度的影响因素，答案以文字解释和论述的形式呈现，没有涉及选择、判断或计算。 | 知识层次: 题目考查对聚合物玻璃化转变温度影响因素的基本概念记忆和理解，涉及的知识点较为基础，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求描述影响聚合物玻璃化转变温度的因素，但正确选项已经列出了四个主要因素，考生只需识别和选择这些因素。这需要考生对相关概念有一定的理解和记忆，但不需要进行复杂的分析或比较。因此，该题目在选择题型中属于等级2的难度。", "convertible": true, "correct_option": "There are many factors affecting the glass transition temperature, usually including (1) chain flexibility; (2) the influence of intermolecular forces; (3) the effect of copolymerization; (4) the influence of plasticizers, etc.", "choice_question": "Which of the following best describes the influencing factors of the glass transition temperature of polymers?", "conversion_reason": "The answer is a standard list of factors, which can be converted into a multiple-choice question format by presenting these factors as options and asking the student to select the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chain flexibility and intermolecular forces are the primary determinants, with plasticizers having negligible effect below 5% concentration", "B": "Crystallinity percentage is the dominant factor, with glass transition temperature increasing linearly with crystallinity", "C": "Crosslinking density shows an inverse square relationship with glass transition temperature in all polymer systems", "D": "Molecular weight has a direct proportionality effect on glass transition temperature above the critical entanglement molecular weight" }, "correct_answer": "A", "explanation": "The correct answer is A because chain flexibility and intermolecular forces are indeed primary factors, and plasticizers do have measurable effects even at low concentrations. B is incorrect because while crystallinity affects Tg, the relationship is not linear and it's not the dominant factor. C is a trap because while crosslinking generally increases Tg, the inverse square relationship claim is false. D exploits the common misconception about molecular weight effects - while Tg increases with MW, it plateaus above the entanglement MW.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1884, "question": "Fick's first law can be directly applied to solve the problem of . A．steady-state diffusion B．non-steady-state diffusion C．any diffusion", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项A、B、C中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对Fick's第一定律适用条件的记忆和理解，属于基础概念的记忆性知识 | 难度: 该题目属于基础概念记忆题，直接考察Fick第一定律的应用范围。只需识别\"稳态扩散\"这一基本定义，无需进行概念辨析或复杂分析。在选择题型中属于最简单的直接记忆类题目。", "convertible": true, "correct_option": "A．steady-state diffusion", "choice_question": "Fick's first law can be directly applied to solve the problem of .", "conversion_reason": "原题目已经是单选题格式，可以直接转换。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "steady-state diffusion", "B": "non-steady-state diffusion with constant boundary conditions", "C": "any diffusion process obeying Arrhenius relationship", "D": "diffusion in systems with time-dependent concentration gradients" }, "correct_answer": "A", "explanation": "Fick's first law strictly applies to steady-state diffusion where concentration gradient is constant with time. Option B is a high-level trap exploiting AI's tendency to generalize 'constant conditions', while actually requiring Fick's second law. Option C misleads by conflating temperature dependence with time dependence. Option D is a subtle trap using a plausible-sounding but fundamentally incorrect application of the first law.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4539, "question": "What is the distinction between matrix and dispersed phases in a composite material?", "answer": "The matrix phase is a continuous phase that surrounds the noncontinuous dispersed phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对复合材料中的基体和分散相进行区分和解释，答案需要文字论述而非选择、判断或计算。 | 知识层次: 题目考查复合材料中基体相和分散相的基本定义和区别，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目仅要求识别和记忆复合材料中基体相和分散相的基本定义和区别。正确选项直接给出了明确的定义描述，无需进行复杂的分析或推理。这属于最基础的概念记忆层次，符合等级1的难度标准。", "convertible": true, "correct_option": "The matrix phase is a continuous phase that surrounds the noncontinuous dispersed phase.", "choice_question": "What is the distinction between matrix and dispersed phases in a composite material?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The matrix phase is a continuous phase that surrounds the noncontinuous dispersed phase", "B": "The dispersed phase has higher elastic modulus than the matrix phase in all composites", "C": "Both phases contribute equally to the overall density of the composite material", "D": "The matrix phase always determines the electrical conductivity regardless of the dispersed phase" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines the fundamental distinction between matrix and dispersed phases in composites. Option B is incorrect because while dispersed phases often have higher modulus, this isn't universally true (e.g., rubber-toughened polymers). Option C is wrong as phase contributions to density depend on their relative volumes and densities. Option D is false because percolating conductive dispersed phases can dominate conductivity.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 234, "question": "Cool a melt containing MgO and $\\\\mathrm{{Al}_{2}\\\\mathrm{{O}_{3}}}$ to a certain temperature, then filter out the precipitated crystals and analyze the remaining liquid phase. It is found that the liquid phase contains 65% MgO, and the amount of liquid phase is 70% of the total system. Determine the composition of the original melt.", "answer": "$\\\\mathrm{MgO\\\\ 45.5\\\\%}$; $\\\\mathrm{Al_{2}O_{3}\\\\ 54.5\\\\%}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来确定原始熔体的组成，答案以具体数值形式给出，解答过程涉及物质平衡和相图分析等计算步骤。 | 知识层次: 题目需要进行多步计算和概念关联，包括相平衡和成分分析的综合应用，但不需要复杂的推理分析或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解相图概念并进行多步计算。题目涉及质量平衡和组分分配的综合分析，解题步骤包括设定变量、建立方程和求解，但选项提供了明确的目标减少了部分复杂性。", "convertible": true, "correct_option": "MgO 45.5%; Al2O3 54.5%", "choice_question": "Cool a melt containing MgO and Al2O3 to a certain temperature, then filter out the precipitated crystals and analyze the remaining liquid phase. It is found that the liquid phase contains 65% MgO, and the amount of liquid phase is 70% of the total system. Determine the composition of the original melt.", "conversion_reason": "The question is a calculation problem with a specific and definitive answer, making it suitable for conversion into a multiple-choice format. The correct option can be directly derived from the provided answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "MgO 45.5%; Al2O3 54.5%", "B": "MgO 55.5%; Al2O3 44.5%", "C": "MgO 65%; Al2O3 35%", "D": "MgO 70%; Al2O3 30%" }, "correct_answer": "A", "explanation": "正确答案A是通过质量平衡计算得出的：设原始熔体中MgO为x%，则0.7×65 + 0.3×MgO_in_crystal = x。根据相图，此时析出的是纯Al2O3晶体，故MgO_in_crystal=0，解得x=45.5%。干扰项B利用常见计算错误（忽略晶体中MgO含量）；C直接采用液相组成，忽略相分离；D混淆了液相比例与组成比例，都是针对AI常见错误模式设计的。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4741, "question": "A cylindrical specimen of a nickel alloy having an elastic modulus of 207 \\mathrm{GPa}\\left(30 × 10^{6} psi\\right) and an original diameter of 10.2 mm(0.40 in.) experiences only elastic deformation when a tensile load of 8900N\\left(2000 lb f_{\\mathrm{f}}\\right) is applied. Compute the maximum length of the specimen before deformation if the maximum allowable elongation is 0.25 mm(0.010 in.).", "answer": "the maximum length of the specimen before deformation is 0.475{m} (475mm or 18.7 in.).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解最大长度，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括应用胡克定律、应力应变关系以及几何变形公式，涉及概念关联和综合分析，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要综合运用弹性模量、应力应变关系、几何变形等多重概念，并进行多步骤计算（包括应力计算、应变推导和几何关系转换）。虽然题目提供了关键参数，但解题过程涉及多个物理公式的串联应用和单位转换，对学生的概念关联和综合分析能力要求较高。", "convertible": true, "correct_option": "0.475 m (475 mm or 18.7 in.)", "choice_question": "A cylindrical specimen of a nickel alloy having an elastic modulus of 207 GPa (30 × 10^6 psi) and an original diameter of 10.2 mm (0.40 in.) experiences only elastic deformation when a tensile load of 8900 N (2000 lbf) is applied. Compute the maximum length of the specimen before deformation if the maximum allowable elongation is 0.25 mm (0.010 in.). The maximum length of the specimen before deformation is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.475 m (475 mm)", "B": "0.237 m (237 mm)", "C": "0.95 m (950 mm)", "D": "0.119 m (119 mm)" }, "correct_answer": "A", "explanation": "正确答案A通过Hooke定律计算得出：首先计算横截面积A=πr²=81.67×10⁻⁶ m²，应力σ=F/A=109 MPa，应变ε=σ/E=0.000527，最后L₀=ΔL/ε=0.475 m。干扰项B是正确答案的一半，利用了计算中可能遗漏面积因子或混淆直径/半径的认知偏差。干扰项C是正确答案的两倍，利用了可能错误加倍应变值的直觉陷阱。干扰项D是正确答案的四分之一，利用了可能混淆应力与应变关系的多层次验证陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1354, "question": "According to solidification theory, what is the fundamental principle of refining grain size by increasing undercooling?", "answer": "Increasing undercooling. Grain size depends on the relative relationship between nucleation rate and grain growth velocity. When undercooling is significantly high, the increase rate of nucleation surpasses that of grain growth, thus enhancing undercooling ensures N > G and widens the gap between them, leading to grain refinement.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释凝固理论中通过增加过冷度细化晶粒的基本原理，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释通过增加过冷度细化晶粒的基本原理，涉及成核速率与晶粒生长速度的相对关系，需要综合运用凝固理论中的概念进行推理分析，解释N>G的机理及其对晶粒细化的影响，思维过程较为深入。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Increasing undercooling", "choice_question": "According to solidification theory, what is the fundamental principle of refining grain size by increasing undercooling?", "conversion_reason": "The answer is a standard concept in solidification theory, making it suitable for conversion to a multiple-choice format where the correct option is clearly identifiable.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increasing undercooling raises nucleation rate exponentially while limiting growth rate linearly", "B": "Higher undercooling decreases surface energy at solid-liquid interface", "C": "Undercooling promotes columnar grain formation by directional heat extraction", "D": "The Gibbs-Thomson effect becomes dominant at high undercooling levels" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental competition between nucleation and growth kinetics. B is a surface thermodynamics misconception (undercooling actually increases interfacial energy). C reverses the effect (undercooling promotes equiaxed grains). D misapplies the Gibbs-Thomson effect (relevant for nanoparticles, not bulk solidification).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4578, "question": "Define the term 'elemental' as it pertains to semiconducting materials and provide an example.", "answer": "elemental--Ge and Si.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求定义术语并提供例子，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对\"elemental\"这一基本术语的定义记忆和简单举例，属于基础概念的记忆性知识范畴 | 难度: 在选择题型中，该题目仅要求考生记忆并选择正确的元素示例（Ge和Si），属于基础概念记忆层次。题目不涉及解释或复杂概念体系，仅需简单回忆半导体材料的基本定义和分类，因此属于最低难度等级。", "convertible": true, "correct_option": "Ge and Si", "choice_question": "Which of the following are examples of elemental semiconducting materials?", "conversion_reason": "The answer is a standard pair of examples (Ge and Si) that can be presented as a correct option among other possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ge and Si", "B": "GaAs and InP", "C": "C (diamond) and Sn (gray tin)", "D": "SiO2 and Al2O3" }, "correct_answer": "A", "explanation": "The correct answer is A because Ge (germanium) and Si (silicon) are classic elemental semiconductors, meaning they consist of single elements with semiconducting properties. Option B is incorrect as GaAs and InP are compound semiconductors, not elemental. Option C is a cognitive bias trap: while diamond and gray tin are elemental allotropes, diamond is an insulator and gray tin's semiconducting properties are highly temperature-dependent. Option D exploits material science confusion by listing common insulators (SiO2 and Al2O3) that are frequently associated with semiconductor devices but are not semiconductors themselves.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 932, "question": "What is a lattice parameter?", "answer": "Lattice parameters are the fundamental parameters that describe the geometric shape of a unit cell, consisting of six parameters: the three edge lengths a, b, c and the three angles α, β, γ between them.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"lattice parameter\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即晶格参数的定义和组成，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别晶格参数的基本定义，属于基础概念记忆层次。题目直接给出了晶格参数的定义和组成要素，不需要进行复杂的分析或推理，因此属于最简单的难度等级。", "convertible": true, "correct_option": "Lattice parameters are the fundamental parameters that describe the geometric shape of a unit cell, consisting of six parameters: the three edge lengths a, b, c and the three angles α, β, γ between them.", "choice_question": "Which of the following best describes lattice parameters?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by asking for the best description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The fundamental parameters describing the geometric shape of a unit cell, including edge lengths and interaxial angles", "B": "The constants used to calculate interatomic spacing in amorphous materials", "C": "The parameters defining the elastic deformation limits of crystalline materials", "D": "The coefficients relating stress to strain in anisotropic materials" }, "correct_answer": "A", "explanation": "The correct answer is A because lattice parameters specifically describe the unit cell geometry in crystalline materials. Option B is incorrect as it confuses lattice parameters with radial distribution functions used in amorphous materials. Option C is a cognitive bias trap, mixing lattice parameters with mechanical properties. Option D exploits professional intuition by using terminology from elasticity theory that's unrelated to crystallography.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2249, "question": "Analyze the main reasons for dislocations promoting nucleation, focusing on the case where the new phase nucleates on the dislocation line", "answer": "When the new phase nucleates on the dislocation line, the dislocation disappears at the nucleation site, and the released elastic strain energy reduces the nucleation work, thereby promoting nucleation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析位错促进形核的主要原因，并聚焦于新相在位错线上形核的情况。答案需要文字解释和论述，而非选择、判断或计算。 | 知识层次: 题目要求分析位错促进形核的主要原因，并聚焦于新相在位错线上形核的情况。这需要综合运用位错理论、形核理论以及弹性应变能等知识，进行推理分析和机理解释。思维过程涉及多个概念的关联和深入理解，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。理由如下：", "convertible": true, "correct_option": "When the new phase nucleates on the dislocation line, the dislocation disappears at the nucleation site, and the released elastic strain energy reduces the nucleation work, thereby promoting nucleation.", "choice_question": "Which of the following describes the main reason dislocations promote nucleation when the new phase nucleates on the dislocation line?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description of the phenomenon.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When the new phase nucleates on the dislocation line, the dislocation disappears at the nucleation site, and the released elastic strain energy reduces the nucleation work, thereby promoting nucleation", "B": "Dislocations increase the local atomic vibration frequency, which provides additional thermal energy to overcome the nucleation barrier", "C": "The stress field around dislocations creates preferential sites for solute segregation, lowering the interfacial energy between matrix and nucleus", "D": "Dislocation cores act as high-diffusivity paths that accelerate atomic transport to the nucleation site" }, "correct_answer": "A", "explanation": "The correct answer is A because the disappearance of dislocations at nucleation sites releases stored elastic strain energy, directly reducing the thermodynamic barrier for nucleation. Option B is a cognitive bias trap, incorrectly suggesting thermal effects when the key mechanism is strain energy release. Option C is a professional intuition trap, describing a real phenomenon (solute segregation) but not the primary nucleation mechanism. Option D is a multi-level verification trap, mixing valid diffusion effects with the incorrect primary reason for nucleation promotion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 197, "question": "The surface tension of alumina under vacuum is approximately $0.9\\\\mathrm{N/m}$, the surface tension of liquid iron is $1.72\\\\mathrm{N/m}$, and the interfacial tension between liquid iron and alumina under the same conditions is $2.3\\\\mathrm{N/m}$. What is the contact angle? Can liquid iron wet alumina?", "answer": "$$\\\\cos\\\\theta=\\\\frac{\\\\gamma_{s v}-\\\\gamma_{s l}}{\\\\gamma_{b}}=\\\\frac{0.9-2.3}{1.72}=0.814,\\\\theta=144.5^{0}>90^{\\\\circ},B T\\\\cup\\\\gamma_{\\\\mathrm{SRE}}\\\\times1875^{\\\\circ}$$ So it cannot wet.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解接触角，并判断液体铁是否能润湿氧化铝。答案中包含了具体的计算过程和数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及表面张力和接触角的基本公式应用，通过直接套用公式进行计算即可得出结果，不需要多步计算或综合分析。虽然需要理解表面张力和接触角的概念，但整体思维过程较为直接和简单。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要理解表面张力和接触角的概念，但解题步骤相对直接，只需套用给定的公式进行计算即可得出答案。不需要复杂的分析或多步骤推理，因此难度等级为2。", "convertible": true, "correct_option": "144.5°, cannot wet", "choice_question": "Given the surface tension of alumina under vacuum is approximately 0.9 N/m, the surface tension of liquid iron is 1.72 N/m, and the interfacial tension between liquid iron and alumina under the same conditions is 2.3 N/m, what is the contact angle and can liquid iron wet alumina?", "conversion_reason": "The question involves a calculation with a specific answer, which can be converted into a multiple-choice format with the correct option derived from the provided solution.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "144.5°, cannot wet", "B": "35.5°, can wet", "C": "90°, partial wetting", "D": "180°, complete non-wetting" }, "correct_answer": "A", "explanation": "The correct answer is calculated using Young's equation: cosθ = (γ_alumina - γ_interface)/γ_iron = (0.9 - 2.3)/1.72 = -0.814, giving θ = 144.5°. Since θ > 90°, wetting cannot occur. Option B reverses the surface tension terms in the calculation. Option C assumes neutral wetting without calculation. Option D represents a theoretical extreme case not supported by the given data.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1834, "question": "What are the two components of the activation energy for intrinsic diffusion?", "answer": "Vacancy formation energy and particle migration energy", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和列举激活能的两个组成部分，答案以文字形式给出，不需要计算或选择 | 知识层次: 题目考查对激活能组成部分的基础概念记忆，仅需回答两个关键术语，无需深入分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即激活能的两个组成部分。学生只需回忆并识别\"空位形成能\"和\"粒子迁移能\"这两个术语即可作答，无需进行概念解释或复杂分析。这属于最基本的概念记忆题，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Vacancy formation energy and particle migration energy", "choice_question": "What are the two components of the activation energy for intrinsic diffusion?", "conversion_reason": "The answer is a standard terminology and can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Vacancy formation energy and particle migration energy", "B": "Lattice vibration energy and electron excitation energy", "C": "Surface energy and grain boundary diffusion energy", "D": "Dislocation formation energy and stacking fault energy" }, "correct_answer": "A", "explanation": "The correct answer is A because intrinsic diffusion involves both the energy required to form vacancies (vacancy formation energy) and the energy needed for atoms to move between lattice sites (particle migration energy). Option B is a cognitive bias trap, combining two real but irrelevant energy types that sound plausible for atomic motion. Option C exploits surface/grain boundary confusion, which applies to extrinsic not intrinsic diffusion. Option D uses dislocation-related terms that are important in plasticity but not diffusion mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1234, "question": "Fracture characteristics of metals: (1) One form of brittle fracture is transgranular cleavage. (2) Cleavage fractures mainly exhibit river patterns. (3) The propagation direction of micro-cracks can be determined by the flow direction of the rivers, i.e., the convergence direction of the rivers indicates the crack propagation direction. (4) Some materials exhibit tongue patterns in their ductile fracture surfaces. (5) Ductile fractures mainly manifest as intergranular dimple fracture forms.", "answer": "(2) (3) (5)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目给出了一系列陈述，要求判断哪些陈述是正确的（即选择正确的陈述作为答案）。这种形式符合判断题的特征，即从多个陈述中识别出正确的部分。 | 知识层次: 题目考查金属断裂特征的基础概念记忆，包括脆性断裂和韧性断裂的形貌特征及其判断依据，属于定义和分类的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个关于金属断裂特性的陈述，但主要考察的是对基础概念的理解和判断。正确选项(2)、(3)、(5)需要考生能够区分脆性断裂和韧性断裂的特征，并理解河流花样和舌状花样等微观形貌的含义。虽然涉及多个概念，但都属于基础概念记忆层次，不需要复杂的分析或推理。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "(2) (3) (5)", "choice_question": "Fracture characteristics of metals: (1) One form of brittle fracture is transgranular cleavage. (2) Cleavage fractures mainly exhibit river patterns. (3) The propagation direction of micro-cracks can be determined by the flow direction of the rivers, i.e., the convergence direction of the rivers indicates the crack propagation direction. (4) Some materials exhibit tongue patterns in their ductile fracture surfaces. (5) Ductile fractures mainly manifest as intergranular dimple fracture forms.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All brittle fractures in metals exhibit transgranular cleavage with river patterns that always converge towards the crack initiation site.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While transgranular cleavage is a common brittle fracture mode and often shows river patterns, not all brittle fractures follow this pattern. Some may show intergranular fracture or other features. Additionally, river patterns converge towards the crack propagation direction, not necessarily the initiation site. The use of 'all' and 'always' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4397, "question": "Why must rivets of a 2017 aluminum alloy be refrigerated before they are used?", "answer": "Rivets of a 2017 aluminum alloy must be refrigerated before they are used because, after being solution heat treated, they precipitation harden at room temperature. Once precipitation hardened, they are too strong and brittle to be driven.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么2017铝合金铆钉在使用前必须冷藏，答案需要提供详细的文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目不仅需要理解2017铝合金铆钉的热处理过程，还需要分析其在室温下的时效硬化行为及其对机械性能的影响。这涉及到材料科学中的相变、强化机制以及工艺控制等多个知识点的综合运用和推理分析。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Rivets of a 2017 aluminum alloy must be refrigerated before they are used because, after being solution heat treated, they precipitation harden at room temperature. Once precipitation hardened, they are too strong and brittle to be driven.", "choice_question": "Why must rivets of a 2017 aluminum alloy be refrigerated before they are used?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To prevent premature precipitation hardening that would make them too brittle for riveting", "B": "To reduce thermal expansion during installation for better dimensional accuracy", "C": "To maintain the metastable supersaturated solid solution state until forming is complete", "D": "To slow down the diffusion of copper atoms and preserve workability" }, "correct_answer": "A", "explanation": "The correct answer is A because 2017 aluminum alloy rivets are solution heat treated and will naturally age (precipitation harden) at room temperature, becoming too strong and brittle for driving. Option B exploits thermal expansion intuition but is irrelevant to the hardening mechanism. Option C sounds technically accurate but describes the general purpose of refrigeration rather than the specific consequence of not doing so. Option D uses correct metallurgical terminology but misapplies it to the wrong stage of the process.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4120, "question": "Do carbon-carbon composites exhibit high tensile moduli at elevated temperatures?", "answer": "Carbon-carbon composites have high tensile moduli at elevated temperatures.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（碳碳复合材料在高温下是否具有高拉伸模量），答案直接给出了对错判断。这符合判断题的特征。 | 知识层次: 题目考查对碳碳复合材料基本性能的记忆和理解，属于基础概念层面的知识，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即碳-碳复合材料在高温下的拉伸模量特性。正确选项直接陈述了定义性知识，无需复杂理解或分析，属于最基本的概念正误判断。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Carbon-carbon composites have high tensile moduli at elevated temperatures.", "choice_question": "Do carbon-carbon composites exhibit high tensile moduli at elevated temperatures?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All carbon-carbon composites maintain their room-temperature tensile moduli when heated above 1000°C", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While carbon-carbon composites generally retain good mechanical properties at high temperatures, their tensile moduli typically decrease with increasing temperature due to thermal expansion effects and microstructural changes. The use of 'all' makes this statement false as some specially engineered composites may show different behavior. Additionally, the specific temperature threshold of 1000°C requires precise knowledge of composite behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3412, "question": "What is the meaning of the commonly referred terms 'ordinary steel', 'quality steel', and 'high-quality steel'?", "answer": "It mainly refers to the difference in the mass fraction of phosphorus and sulfur. Ordinary steel: $w_{P}\\\\leqslant0.045\\\\%$ $w_{\\\\mathrm{S}}\\\\leqslant0.05\\\\%;$ quality steel: $\\\\scriptstyle w_{\\\\mathrm{P}}\\\\leq0.035\\\\%,w_{\\\\mathrm{S}}\\\\leq0.035\\\\%;$ high-quality steel: $w_{\\\\mathrm{P}}{\\\\le}0.025\\\\%$ $w_{\\\\mathrm{S}}{\\\\leq}0.025\\\\%$", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释术语的含义，答案提供了详细的文字说明和具体数值标准，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目主要考查对普通钢、优质钢和高级优质钢的定义和分类的记忆，涉及的是基本概念和分类标准，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个术语的定义和分类，但主要考察的是对\"ordinary steel\"、\"quality steel\"和\"high-quality steel\"这三个基本概念的记忆和理解，特别是对磷和硫含量限制的具体数值的记忆。题目没有要求复杂的分析或推理过程，只需正确识别和匹配给定的数值范围与相应的钢材分类即可。因此，在选择题型内属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "It mainly refers to the difference in the mass fraction of phosphorus and sulfur. Ordinary steel: $w_{P}\\leqslant0.045\\%$ $w_{\\mathrm{S}}\\leqslant0.05\\%;$ quality steel: $\\scriptstyle w_{\\mathrm{P}}\\leq0.035\\%,w_{\\mathrm{S}}\\leq0.035\\%;$ high-quality steel: $w_{\\mathrm{P}}{\\le}0.025\\%$ $w_{\\mathrm{S}}{\\leq}0.025\\%$", "choice_question": "What is the meaning of the commonly referred terms 'ordinary steel', 'quality steel', and 'high-quality steel'?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It mainly refers to the difference in the mass fraction of phosphorus and sulfur: Ordinary steel (P≤0.045%, S≤0.05%), Quality steel (P≤0.035%, S≤0.035%), High-quality steel (P≤0.025%, S≤0.025%)", "B": "It depends on carbon content: Ordinary steel (C≤0.25%), Quality steel (0.25%0.6%)", "C": "It's determined by yield strength: Ordinary steel (σs≤235MPa), Quality steel (235MPa<σs≤355MPa), High-quality steel (σs>355MPa)", "D": "It's classified by alloying elements: Ordinary steel (no alloys), Quality steel (1-3% alloy content), High-quality steel (>3% alloy content)" }, "correct_answer": "A", "explanation": "The correct answer is A because the classification is primarily based on impurity control (P and S content). Option B exploits the common cognitive bias associating quality with carbon content. Option C uses a plausible but incorrect mechanical property classification. Option D creates confusion by mixing the classification system with alloy steel categories, which is a different classification dimension.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3220, "question": "A face-centered cubic single crystal is stretched with [131] as the force axis. When the tensile stress is 1×10^7Pa, determine the resolved shear stress on the (111)[1\\\\overline{1}0] slip system.", "answer": "For the (111)[1\\\\overline{1}0] slip system, cosφ=5√33/33; cosλ=-√22/11. Therefore, τ3=1×10^7×(5√33/33)×(-√22/11)=3.7×10^6Pa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定特定滑移系上的分切应力，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目需要计算面心立方单晶在特定拉伸方向下的分切应力，涉及晶体学方向指数的计算、施密特因子的求解以及分切应力公式的应用。虽然计算步骤明确，但需要理解晶体学方向与滑移系统的关系，并进行多步计算和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体滑移系统的概念，掌握分解剪应力的计算方法，并进行多步向量运算和三角函数计算。虽然题目提供了正确选项，但解题过程涉及方向余弦计算、向量点积和综合分析，比单纯的概念选择题更复杂。", "convertible": true, "correct_option": "3.7×10^6Pa", "choice_question": "A face-centered cubic single crystal is stretched with [131] as the force axis. When the tensile stress is 1×10^7Pa, the resolved shear stress on the (111)[1\\overline{1}0] slip system is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.7×10^6Pa", "B": "1.2×10^7Pa", "C": "5.1×10^6Pa", "D": "2.9×10^6Pa" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算滑移系(111)[1\\overline{1}0]在[131]拉伸方向上的施密特因子得到的。干扰项B利用了弹性模量计算的直觉陷阱，将总应力直接作为剪切应力。干扰项C设计为接近但错误计算了施密特因子。干扰项D则基于常见但错误的晶面指数计算方式。这些干扰项都利用了材料科学中常见的计算误区。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2394, "question": "In a crystal, there is a pair of parallel edge dislocations on the slip plane. How large should their spacing be to prevent movement due to their interaction? Assume the slip resistance (shear stress) of the dislocation is $\\\\square A^{\\\\prime\\\\prime}\\\\approx10^{5}Pa$, $1=0.3$, $G=5\\\\times10^{10}Pa$ (express the answer in terms of b).", "answer": "Two parallel edge dislocations (denoted as A and B), with dislocation A located on the $\\\\underline{{\\\\underline{{\\\\pi}}}}$ axis of the coordinate frame. The force per unit length exerted by dislocation A on parallel dislocation B at position $(x,y)$ in the slip direction is F. Since both dislocations are on the same slip plane, the force is $F_{s}^{\\\\mathrm{A\\\\toB}}=\\\\frac{G b^{2}}{2\\\\pi(1-\\\\nu)}\\\\frac{1}{x}$ G²1, where x is the distance between the two dislocations. When this force equals or exceeds the resistance $\\\\cdot E_{1}b$ that the dislocation must overcome to slip, the two dislocations can slide. Therefore, when $$\\\\leq\\\\frac{\\\\vec{\\\\left(r\\\\right)}^{h}}{\\\\underline{{\\\\vec{2}\\\\pi(1-\\\\nu^{\\\\prime})}}}\\\\frac{1}{\\\\tau_{\\\\perp}}$$, the two dislocations will slide. That is, $$ \\\\displaystyle{x\\\\leq\\\\frac{G b}{2\\\\pi(1-\\\\nu)}\\\\frac{1}{\\\\tau_{\\\\mathrm{pe}}}}{=\\\\frac{5\\\\times10^{10}b}{2\\\\pi(1-0.3)}\\\\frac{1}{9.8\\\\times10^{5}}}{=1.16\\\\times10^{4}b}$$. If the two dislocations have the same sign, they will move toward each other until the distance between them is less than the calculated $^\\\\texttt{I}$ and then remain stationary. If the two dislocations have opposite signs, they will attract and annihilate each other when the distance between them is less than the calculated $x$. The two dislocations will remain stationary only if the distance between them is greater than $\\\\gamma^{-}$. The force in the climb direction is 0, so no climb will occur regardless of the distance between the two dislocations.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定两个平行刃位错之间的临界间距，以防止它们因相互作用而移动。解答过程中涉及到了具体的公式推导和数值代入计算，最终给出了一个具体的数值结果（1.16×10^4b），这符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要理解位错相互作用力的公式应用，并进行数值计算。虽然不需要复杂的推理分析或创新应用，但需要综合运用材料科学中的位错理论和力学知识来解决问题。 | 难度: 在选择题中属于中等偏上难度，需要理解位错相互作用的基本概念，掌握剪切应力与位错间距的关系，并进行多步计算。题目涉及平行刃位错在滑移面上的相互作用力计算，需要将理论公式与给定数值结合，最终推导出临界间距。虽然题目提供了部分公式，但仍需要考生综合运用材料力学和位错理论的知识来完成解答。", "convertible": true, "correct_option": "1.16×10⁴b", "choice_question": "In a crystal, there is a pair of parallel edge dislocations on the slip plane. How large should their spacing be to prevent movement due to their interaction? Assume the slip resistance (shear stress) of the dislocation is ≈10⁵Pa, ν=0.3, G=5×10¹⁰Pa (express the answer in terms of b).", "conversion_reason": "The calculation yields a specific numerical answer (1.16×10⁴b), which can be presented as a choice among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.16×10⁴b", "B": "5.79×10³b", "C": "2.32×10⁴b", "D": "8.66×10³b" }, "correct_answer": "A", "explanation": "The correct answer is derived from the equilibrium condition where the repulsive stress between dislocations equals the slip resistance. The calculation uses τ = Gb/(2π(1-ν)d), solving for d gives d = Gb/(2π(1-ν)τ). Option B is half the correct value, exploiting common factor-of-2 errors in dislocation calculations. Option C is double the correct value, targeting those who confuse shear modulus with Young's modulus. Option D is √3/2 of the correct value, designed to trap those who incorrectly apply trigonometric relationships to dislocation spacing.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4179, "question": "Give the electron configuration for the ion Al3+.", "answer": "The electron configuration for an Al3+ ion is 1s2 2s2 2p6.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出电子排布式，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对电子排布这一基础概念的记忆和理解，仅需直接回忆铝离子(Al3+)的电子排布情况，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目仅要求记忆基础概念（电子排布式），无需解释或复杂推理。属于直接回忆型问题，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "1s2 2s2 2p6", "choice_question": "What is the electron configuration for the ion Al3+?", "conversion_reason": "The answer is a standard and specific electron configuration, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1s2 2s2 2p6", "B": "1s2 2s2 2p6 3s2", "C": "1s2 2s2 2p6 3s2 3p1", "D": "[Ne] 3s2 3p1" }, "correct_answer": "A", "explanation": "Al3+ has lost 3 electrons (2 from 3p and 1 from 3s), leaving it with the same configuration as neon. Option B is the configuration of Mg2+, which could confuse models by similarity in charge. Option C is neutral Al's configuration, exploiting the 'first impression' bias. Option D uses noble gas notation but incorrectly shows the neutral atom configuration, a subtle notation trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2244, "question": "In the regular melt α, the total driving force ΔG for the precipitation of β can be approximately expressed as ΔG=RT[x_o ln(x_o/x_e)+(1-x_o)ln((1-x_o)/(1-x_e))]-2Ω(x_o-x_e)^2. Given T=600K, x_o=0.1, x_e=0.02, Ω=0, use this expression to estimate the total driving force for α→α′+β.", "answer": "Given T=600K, x_o=0.1, x_e=0.02, R=8.31 J/(mol·K). ΔG=RT[x_o ln(x_o/x_e)+(1-x_o)ln((1-x_o)/(1-x_e))]=8.31×600×[0.1 ln(0.1/0.02)+(1-0.1)ln((1-0.1)/(1-0.02))]=420.8 J/mol", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求使用给定的公式和参数进行数值计算，最终得出一个具体的数值结果。答案展示了具体的计算步骤和最终结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，不需要多步推理或综合分析，仅需将给定数值代入公式进行计算即可。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目提供了所有必要的参数和公式，只需要将给定的数值代入公式中进行简单的计算即可得到答案。不需要理解多个概念或进行复杂的分析，解题步骤非常直接和简单。", "convertible": true, "correct_option": "420.8 J/mol", "choice_question": "In the regular melt α, the total driving force ΔG for the precipitation of β can be approximately expressed as ΔG=RT[x_o ln(x_o/x_e)+(1-x_o)ln((1-x_o)/(1-x_e))]-2Ω(x_o-x_e)^2. Given T=600K, x_o=0.1, x_e=0.02, Ω=0, use this expression to estimate the total driving force for α→α′+β. The estimated total driving force is:", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion to a multiple-choice format. The correct answer is a specific value (420.8 J/mol), which can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "420.8 J/mol", "B": "210.4 J/mol", "C": "841.6 J/mol", "D": "105.2 J/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (420.8 J/mol) calculated using the given formula with Ω=0. Option B (210.4 J/mol) is half the correct value, exploiting the common error of forgetting to multiply by R. Option C (841.6 J/mol) doubles the correct value, targeting those who might incorrectly square the logarithmic terms. Option D (105.2 J/mol) is one-fourth the correct value, designed to trap those who might confuse the natural log with log base 10.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3374, "question": "What elements are commonly used to improve the tempering stability of steel?", "answer": "Common elements: Si, Co.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举常见的用于提高钢的回火稳定性的元素，答案以简短的文字形式给出，不需要计算或选择，属于简答题类型。 | 知识层次: 题目考查对钢的回火稳定性改善常用元素的基本记忆，属于基础概念的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆常见的用于提高钢的回火稳定性的元素（Si、Co），属于基础概念记忆的范畴。题目不涉及复杂的概念解释或体系阐述，解题步骤简单直接，只需回忆相关知识即可作答。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Si, Co", "choice_question": "Which of the following elements are commonly used to improve the tempering stability of steel?", "conversion_reason": "The answer is a standard set of elements (Si, Co), which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Si, Co", "B": "Cr, Mo", "C": "Ni, Mn", "D": "V, W" }, "correct_answer": "A", "explanation": "Si and Co are correct because Si increases the tempering resistance by inhibiting carbide formation, while Co delays the softening process during tempering. Option B (Cr, Mo) is a cognitive bias trap as these elements are commonly associated with hardenability improvement rather than tempering stability. Option C (Ni, Mn) exploits the intuition that these are common alloying elements, but they actually reduce tempering stability. Option D (V, W) is a multi-level verification trap - while these elements form stable carbides, they primarily affect secondary hardening rather than tempering stability.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3425, "question": "Which commonly used alloying elements belong to the elements that close the γ region?", "answer": "Silicon, chromium, tungsten, molybdenum, phosphorus, vanadium, titanium, and aluminum close the γ region.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举特定类别的合金元素，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对合金元素分类的基础概念记忆，只需回答哪些元素属于关闭γ区的元素，不涉及复杂分析或应用。 | 难度: 该题目属于选择题型，考察的是对合金元素分类的基础概念记忆。虽然需要记忆多个元素（硅、铬、钨、钼、磷、钒、钛和铝）属于关闭γ区域的元素，但不需要复杂的分析或推理过程。在选择题型中，这属于中等难度，因为需要记住并识别多个相关元素，但不需要深入理解或应用这些概念。", "convertible": true, "correct_option": "Silicon, chromium, tungsten, molybdenum, phosphorus, vanadium, titanium, and aluminum", "choice_question": "Which of the following groups of elements are commonly used alloying elements that close the γ region?", "conversion_reason": "The answer is a standard list of elements, which can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct group of elements.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Silicon, chromium, tungsten, molybdenum, phosphorus, vanadium, titanium, and aluminum", "B": "Nickel, manganese, carbon, nitrogen, copper, and cobalt", "C": "Zinc, magnesium, lithium, beryllium, and calcium", "D": "Gold, silver, platinum, palladium, and rhodium" }, "correct_answer": "A", "explanation": "The correct answer is A because these elements are known to close the γ region in iron-based alloys by stabilizing the α-ferrite phase. Option B contains elements that actually expand the γ region (austenite stabilizers), exploiting the AI's potential confusion between γ-closing and γ-expanding elements. Option C includes light metals that are rarely used as alloying elements in steel, targeting the AI's possible overgeneralization of alloying principles. Option D uses noble metals that are incompatible with iron alloys, testing the AI's ability to recognize contextually inappropriate options despite their material science relevance.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2206, "question": "A cold-drawn steel wire rope was used to hoist a large workpiece into a furnace and was heated together with the workpiece to $1,000^{\\circ}\\mathrm{C}$. Upon completion of heating, when the workpiece was lifted out, the steel wire rope broke. Analyze the reason for this.", "answer": "The processing of the cold-drawn steel wire rope is a cold-working process. Due to work hardening, the strength and hardness of the steel wire increase, thereby enhancing its load-bearing capacity. When heated, if the temperature exceeds its recrystallization temperature, the steel wire rope undergoes recrystallization, leading to a reduction in strength and hardness. Once the external load exceeds its load-bearing capacity, it will break.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析钢丝绳断裂的原因，答案提供了详细的文字解释和论述，涉及冷加工、加工硬化、再结晶等材料科学概念，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求分析冷拔钢丝绳在高温下断裂的原因，涉及冷加工、加工硬化、再结晶温度等多个概念的综合运用和机理解释。需要理解材料在不同温度下的行为变化，并分析其与断裂现象的因果关系，属于复杂分析和推理的范畴。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The processing of the cold-drawn steel wire rope is a cold-working process. Due to work hardening, the strength and hardness of the steel wire increase, thereby enhancing its load-bearing capacity. When heated, if the temperature exceeds its recrystallization temperature, the steel wire rope undergoes recrystallization, leading to a reduction in strength and hardness. Once the external load exceeds its load-bearing capacity, it will break.", "choice_question": "A cold-drawn steel wire rope was used to hoist a large workpiece into a furnace and was heated together with the workpiece to $1,000^{\\circ}\\mathrm{C}$. Upon completion of heating, when the workpiece was lifted out, the steel wire rope broke. What is the reason for this?", "conversion_reason": "The answer is a standard explanation involving material science concepts, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": "N/A", "perplexity_level": "N/A", "perplexity_reason": "N/A", "missing_info": "N/A" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The cold-drawn steel's dislocation density decreased during heating, causing strength loss", "B": "Thermal expansion mismatch between the wire and workpiece induced fracture", "C": "The steel's elastic modulus dropped below critical value at high temperature", "D": "Carbon diffusion at 1000°C created brittle cementite layers at grain boundaries" }, "correct_answer": "A", "explanation": "The correct answer is A because cold-drawn steel's strength comes from work hardening (high dislocation density). Heating above recrystallization temperature eliminates these dislocations, drastically reducing strength. Option B exploits thermal expansion intuition but ignores that both components were equally heated. Option C uses a real phenomenon (modulus reduction) but this alone wouldn't cause sudden failure. Option D describes a real metallurgical process but requires much longer heating times than this scenario.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1080, "question": "Write all the crystal planes included in the {110} plane family of the cubic crystal system.", "answer": "(110), (101), (011), (110), (101), (011).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举立方晶系中{110}晶面族包含的所有晶面，需要文字描述和具体列举，不涉及选择、判断或计算。 | 知识层次: 题目考查对立方晶系中{110}晶面族包含的所有晶面的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目要求列出立方晶系{110}晶面族中包含的所有晶面，这只需要记忆立方晶系晶面族的对称性规则即可直接得出答案。不需要进行复杂的概念解释或分析，属于最基础的概念记忆性知识。", "convertible": true, "correct_option": "(110), (101), (011), (110), (101), (011)", "choice_question": "Which of the following lists all the crystal planes included in the {110} plane family of the cubic crystal system?", "conversion_reason": "The answer is a standard set of terms (crystal planes) which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(110), (101), (011), (110), (101), (011)", "B": "(110), (101), (011)", "C": "(110), (101), (011), (100), (010), (001)", "D": "(110), (101), (011), (111), (111), (111)" }, "correct_answer": "A", "explanation": "The correct answer A includes all 6 equivalent planes in the {110} family for cubic crystals, accounting for both positive and negative directions. Option B misses the negative index variants, exploiting the common oversight of directional equivalence. Option C incorrectly includes {100} family planes, leveraging confusion between similar-looking plane families. Option D introduces {111} planes, targeting the tendency to mix up frequently discussed plane families in cubic systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4501, "question": "Argon diffuses through a high density polyethylene (HDPE) sheet 40mm thick at a rate of 4.0 × 10^{-7} \\left({cm}^{3} STP / {cm}^{2}-s\\right. at 325 K. The pressures of argon at the two faces are 5000 kPa and 1500 kPa, which are maintained constant. Assuming conditions of steady state, what is the permeability coefficient at 325 K ?", "answer": "the permeability coefficient of ar through hdpe at 325k is 4.57 × 10^{-13} \\frac{{cm}^{3} \\mathrm{stp}·{cm}}{{cm}^{2}-s-\\mathrm{pa}}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解渗透系数，答案是一个具体的计算结果，而不是选择、判断或文字解释。 | 知识层次: 题目涉及多步计算和概念关联，需要应用扩散和渗透系数的相关知识，并进行综合分析。虽然计算过程较为直接，但需要理解稳态扩散条件、压力差的应用以及单位转换等概念，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散速率、压力差和渗透系数的关系，并进行多步计算。虽然题目给出了具体数值，但需要正确应用公式并转换单位，涉及中等应用层次的知识点。", "convertible": true, "correct_option": "4.57 × 10^{-13} \\frac{{cm}^{3} \\mathrm{stp}·{cm}}{{cm}^{2}-s-\\mathrm{pa}}", "choice_question": "Argon diffuses through a high density polyethylene (HDPE) sheet 40mm thick at a rate of 4.0 × 10^{-7} \\left({cm}^{3} STP / {cm}^{2}-s\\right. at 325 K. The pressures of argon at the two faces are 5000 kPa and 1500 kPa, which are maintained constant. Assuming conditions of steady state, what is the permeability coefficient at 325 K?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.57 × 10^{-13} \\frac{{cm}^{3} \\mathrm{stp}·{cm}}{{cm}^{2}-s-\\mathrm{pa}}", "B": "选项B", "C": "选项C", "D": "选项D" }, "correct_answer": "A", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 416, "question": "Multiple slip", "answer": "Multiple slip: When the resolved shear stress on several slip systems is equal and simultaneously reaches the critical resolved shear stress, the phenomenon of simultaneous slip occurs.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Multiple slip\"这一现象进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对\"Multiple slip\"这一基本概念的定义和现象描述，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 该题目属于选择题型中的概念解释和描述难度等级。虽然涉及多个概念（resolved shear stress、slip systems、critical resolved shear stress），但主要考察的是对\"Multiple slip\"这一现象的定义性理解，不需要进行复杂的比较分析或推导。在选择题型中，只需识别和匹配正确选项即可，属于中等偏下的难度水平。", "convertible": true, "correct_option": "Multiple slip: When the resolved shear stress on several slip systems is equal and simultaneously reaches the critical resolved shear stress, the phenomenon of simultaneous slip occurs.", "choice_question": "下列关于Multiple slip的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Multiple slip: When the resolved shear stress on several slip systems is equal and simultaneously reaches the critical resolved shear stress, the phenomenon of simultaneous slip occurs.", "B": "Multiple slip occurs when the dislocation density exceeds a critical threshold, regardless of the resolved shear stress on different slip systems.", "C": "Multiple slip is primarily observed in amorphous materials where the lack of crystalline structure allows for simultaneous activation of multiple slip planes.", "D": "Multiple slip requires the presence of at least five independent slip systems to accommodate arbitrary plastic deformation." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines multiple slip as the simultaneous activation of multiple slip systems when their resolved shear stresses reach the critical value. Option B incorrectly associates multiple slip with dislocation density rather than resolved shear stress. Option C is misleading by suggesting multiple slip occurs in amorphous materials, while it's actually a crystalline phenomenon. Option D confuses multiple slip with the general requirement for polycrystalline ductility (5 independent slip systems).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2987, "question": "What are the two synthesis methods of polymer materials", "answer": "Addition polymerization and condensation polymerization", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举聚合物材料的两种合成方法，答案需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查对聚合物材料合成方法的基本分类记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆聚合物材料的两种基本合成方法（加聚和缩聚），属于基础概念记忆层次。题目仅涉及简单的定义和分类，无需解释或比较分析，解题步骤非常直接，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Addition polymerization and condensation polymerization", "choice_question": "Which of the following are the two synthesis methods of polymer materials?", "conversion_reason": "The answer is a standard pair of terms, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Addition polymerization and condensation polymerization", "B": "Thermal polymerization and photopolymerization", "C": "Chain-growth polymerization and step-growth polymerization", "D": "Bulk polymerization and solution polymerization" }, "correct_answer": "A", "explanation": "The correct answer is A because these are the two fundamental synthesis methods classified by reaction mechanism. Option B uses polymerization initiation methods as distractors. Option C is a common confusion where classification by growth mechanism is mistaken for synthesis methods. Option D uses processing techniques as distractors, which are implementation methods rather than fundamental synthesis approaches.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 75, "question": "What is the effect on crystal stability after forming a solid solution?", "answer": "Stabilizes the crystal lattice and prevents certain polymorphic transitions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释固体溶液对晶体稳定性的影响，答案提供了文字解释和论述，符合简答题的特征 | 知识层次: 题目涉及固体溶液对晶体稳定性的影响，需要理解固体溶液的形成机制及其对晶体结构的影响，属于概念关联和综合分析层次。虽然不涉及复杂计算，但需要对晶体稳定性和多态性转变有较深入的理解。 | 难度: 在选择题中属于中等难度，需要理解固溶体形成对晶体稳定性的影响，并关联晶体结构和多晶型转变的概念。虽然题目涉及综合分析，但在选择题型中通过正确选项可以直接判断，不需要多步计算或深度关联性分析。", "convertible": true, "correct_option": "Stabilizes the crystal lattice and prevents certain polymorphic transitions.", "choice_question": "What is the effect on crystal stability after forming a solid solution?", "conversion_reason": "The answer is a standard and concise description of the effect, making it suitable for conversion to a multiple-choice format where this can be the correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Stabilizes the crystal lattice and prevents certain polymorphic transitions", "B": "Increases lattice entropy leading to spontaneous amorphization", "C": "Creates localized stress fields that always reduce melting temperature", "D": "Induces systematic vacancy ordering that destabilizes the structure" }, "correct_answer": "A", "explanation": "The correct answer is A because solid solutions introduce strain fields and entropy effects that stabilize the host lattice against phase transformations. Option B exploits the entropy misconception by exaggerating its effect to imply amorphization. Option C uses 'always' as an absolute trap when stress fields can actually increase melting points in some systems. Option D sounds plausible by mentioning vacancy ordering but incorrectly asserts it as a universal destabilizing effect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1520, "question": "For a screw dislocation line, the direction of its slip motion is _（21）_ to the Burgers vector", "answer": "（21）perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个单词（perpendicular）来回答问题，属于简答题类型，需要根据知识进行简短回答而非选择或判断。 | 知识层次: 题目考查对螺位错滑移方向与伯格斯矢量关系的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即螺型位错滑移方向与伯氏矢量的关系。题目直接给出了正确选项\"perpendicular\"，无需进行复杂的概念解释或分析，属于最基础的定义简答级别。", "convertible": true, "correct_option": "perpendicular", "choice_question": "For a screw dislocation line, the direction of its slip motion is _ to the Burgers vector", "conversion_reason": "The answer is a standard term (perpendicular), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "parallel", "B": "perpendicular", "C": "at 45° angle", "D": "anti-parallel" }, "correct_answer": "B", "explanation": "The correct answer is B (perpendicular) because for a screw dislocation, the slip motion direction is always perpendicular to both the dislocation line and Burgers vector. Option A (parallel) exploits the common misconception that motion aligns with the Burgers vector. Option C (45° angle) creates confusion with mixed dislocation behavior. Option D (anti-parallel) traps those who confuse edge dislocation behavior with screw dislocations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3971, "question": "On the average, dislocation-dislocation strain interactions are(a) repulsive.(b) attractive.", "answer": "On the average, dislocation-dislocation strain interactions are repulsive.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从两个选项(a)和(b)中选择正确答案 | 知识层次: 题目考查对位错-位错应变相互作用的基本概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需直接回忆位错-位错应变相互作用的基本性质即可作答，无需复杂理解或辨析。", "convertible": true, "correct_option": "repulsive", "choice_question": "On the average, dislocation-dislocation strain interactions are", "conversion_reason": "原题目已经是选择题格式，且选项明确，可以转换为单选题。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "repulsive", "B": "attractive", "C": "neutral", "D": "dependent on Burgers vector orientation" }, "correct_answer": "A", "explanation": "The correct answer is A because on average, dislocation-dislocation strain interactions are repulsive due to the elastic strain fields surrounding dislocations. Option B is a cognitive bias trap - it seems plausible because atomic bonds are attractive, but ignores the dominant elastic strain effect. Option C exploits the misconception that strain fields might cancel out. Option D is a professional intuition trap - while Burgers vector orientation affects interaction strength, it doesn't change the fundamental repulsive nature of the average interaction.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1283, "question": "According to the phase rule, the maximum number of equilibrium phases when the degrees of freedom in a ternary system are zero is", "answer": "4", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目涉及相律的应用，需要根据给定的自由度条件（三元系统中自由度为0）进行计算，得出最大平衡相数。答案是一个具体的数值（4），需要通过公式推导或计算得出。 | 知识层次: 题目考查对相律公式的直接应用，仅需简单计算即可得出答案，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目直接考察对相律公式的应用，只需记住并套用相律公式（F = C - P + 2），其中F为自由度，C为组分数，P为相数。题目中给出自由度F=0，组分数C=3（三元系统），直接代入公式即可得出P=5-2=3，但题目问的是最大平衡相数，因此需要考虑相律的限制条件，最终答案为4。虽然需要理解相律的基本概念，但解题步骤非常直接，属于最基础的公式应用。", "convertible": true, "correct_option": "4", "choice_question": "According to the phase rule, the maximum number of equilibrium phases when the degrees of freedom in a ternary system are zero is:", "conversion_reason": "The original question is a calculation question with a definite numerical answer, which can be easily converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项D", "B": "选项B", "C": "4", "D": "选项C" }, "correct_answer": "C", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1409, "question": "In substitutional solid solutions, by what mechanism do solute atoms diffuse?", "answer": "In substitutional solid solutions, solute atoms diffuse by the vacancy mechanism.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述溶质原子在置换固溶体中的扩散机制，答案提供了详细的文字说明而非选择、判断或计算。 | 知识层次: 题目考查对置换固溶体中溶质原子扩散机制的基本概念记忆，即空位机制的理解和表述，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆基础概念中的定义和基本原理，即溶质原子在置换固溶体中的扩散机制。题目直接给出了正确选项，无需进行复杂的分析或比较，属于最基础的定义简答类型。", "convertible": true, "correct_option": "the vacancy mechanism", "choice_question": "In substitutional solid solutions, by what mechanism do solute atoms diffuse?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "the vacancy mechanism", "B": "interstitial diffusion", "C": "grain boundary sliding", "D": "dislocation climb" }, "correct_answer": "A", "explanation": "The correct answer is A because substitutional diffusion requires vacancies for solute atoms to move. B is incorrect as it describes diffusion mechanism for small atoms moving between lattice sites. C is a deformation mechanism unrelated to diffusion. D is a high-temperature creep mechanism that might be confused due to vacancy involvement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 604, "question": "When a disordered solid solution transforms into an ordered solid solution, the general trend in the change of alloy properties is: electrical conductivity", "answer": "decreases", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释无序固溶体转变为有序固溶体时合金性能的一般变化趋势，答案需要文字解释和论述，而非简单的选择或判断。 | 知识层次: 题目要求解释无序固溶体转变为有序固溶体时导电性变化的趋势，这需要理解固溶体结构变化与导电性之间的关系，涉及多个概念的关联和综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解有序固溶体和无序固溶体的概念，并关联其对导电性能的影响。虽然题目给出了正确选项，但需要考生掌握材料科学中固溶体有序化对电子散射机制的影响这一知识点，并进行综合分析判断。", "convertible": true, "correct_option": "decreases", "choice_question": "When a disordered solid solution transforms into an ordered solid solution, the general trend in the change of alloy properties is: electrical conductivity", "conversion_reason": "The answer is a standard term and can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "increases due to reduced electron scattering", "B": "decreases due to enhanced lattice periodicity", "C": "remains unchanged as Fermi level is preserved", "D": "first increases then decreases with ordering parameter" }, "correct_answer": "B", "explanation": "The correct answer is B because ordering introduces superlattice reflections that increase electron scattering, reducing conductivity. Option A exploits the common misconception that ordering implies 'more regular' structure should increase conductivity. Option C uses the accurate Fermi level preservation fact but incorrectly applies it to conductivity. Option D creates a complex but non-existent trend to trap overthinking models.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 399, "question": "Are the geometric conditions for the following dislocation reaction satisfied? Among them: b1=a/2[110], b2=a/6[12¯1], b3=a/6[211]", "answer": "Geometric conditions: after the reaction b2+b3=a/6[12¯1]+a/6[211]=a/6[330]=a/2[110] before the reaction b1=a/2[110] the geometric conditions are satisfied", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断给定的位错反应几何条件是否满足，答案直接给出了判断结果（满足或不满足），属于判断题的特征。 | 知识层次: 题目要求判断位错反应的几何条件是否满足，涉及基本的向量运算和位错反应的基本原理。虽然需要一定的理解，但主要是直接应用公式和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，主要考察对基本公式的直接套用和简单计算能力。题目要求判断位错反应的几何条件是否满足，解题步骤明确且直接，只需进行简单的矢量相加和比较即可得出正确结论。因此，在选择题型内属于较低难度，符合等级2的标准。", "convertible": true, "correct_option": "Geometric conditions: after the reaction b2+b3=a/6[12¯1]+a/6[211]=a/6[330]=a/2[110] before the reaction b1=a/2[110] the geometric conditions are satisfied", "choice_question": "Are the geometric conditions for the following dislocation reaction satisfied? Among them: b1=a/2[110], b2=a/6[12¯1], b3=a/6[211]", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all cubic crystal systems, the dislocation reaction b1 = b2 + b3 is geometrically possible when the vector sum of b2 and b3 exactly equals b1.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the vector sum condition is necessary, it is not always sufficient for geometric possibility in all cubic systems. The reaction must also satisfy energy considerations (b1^2 > b2^2 + b3^2) and the specific crystal structure may impose additional constraints. This absolute statement fails to account for these additional requirements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4069, "question": "[d] Copper and its alloys form a green tarnish over time, consisting of sulfides and carbonates.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（铜及其合金会随时间形成绿色锈蚀），并要求判断其正确性（答案给出T表示正确），符合判断题的特征。 | 知识层次: 题目考查对铜及其合金表面形成的绿色锈蚀物的基本成分的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，此题属于基本概念正误判断。题目仅要求识别铜及其合金随时间形成绿色锈层（由硫化物和碳酸盐组成）这一事实的正确性，不需要深入理解或分析多个概念。这是最基础的定义性知识记忆题，符合等级1的难度标准。", "convertible": true, "correct_option": "T", "choice_question": "[d] Copper and its alloys form a green tarnish over time, consisting of sulfides and carbonates.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All copper alloys will develop a green patina consisting primarily of copper chloride when exposed to atmospheric conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many copper alloys develop a green patina over time, the composition varies based on environment. The classic green patina (verdigris) consists mainly of copper carbonate and sulfate compounds, not chloride. Additionally, some copper alloys (like beryllium copper) are specifically designed to resist patina formation. The use of 'all' and the incorrect chemical composition make this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 650, "question": "What is the relationship between the corrosion of engineering materials and bonding?", "answer": "The essence of corrosion in engineering materials is the formation and destruction of bonds.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释工程材料的腐蚀与键合之间的关系，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查腐蚀与键合关系的基本概念，属于定义和基本原理的记忆性知识 | 难度: 在选择题型中，该题目仅要求考生记忆并识别腐蚀现象与化学键形成/断裂之间的基本关系。题目考查的是基础概念的定义层面，不需要进行概念解释或复杂体系分析。正确选项直接给出了明确的定义性陈述，属于最基础的选择题难度等级。", "convertible": true, "correct_option": "The essence of corrosion in engineering materials is the formation and destruction of bonds.", "choice_question": "What is the relationship between the corrosion of engineering materials and bonding?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Corrosion involves the breaking of metallic bonds and formation of ionic bonds with environmental elements", "B": "Corrosion is primarily a surface phenomenon unrelated to bulk material bonding", "C": "The rate of corrosion is inversely proportional to the strength of covalent bonds in the material", "D": "Corrosion resistance depends solely on the density of metallic bonds per unit volume" }, "correct_answer": "A", "explanation": "The correct answer is A because corrosion fundamentally involves the oxidation of metal atoms (breaking metallic bonds) and their subsequent reaction with environmental elements like oxygen (forming ionic bonds). B is incorrect because while corrosion starts at surfaces, it's deeply connected to bulk material properties. C is a cognitive bias trap - while bond strength affects corrosion, the relationship isn't simple inverse proportionality. D is a professional intuition trap - while metallic bond density matters, other factors like crystal structure and alloying elements are equally important.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2621, "question": "How many types of bonds exist between atoms?", "answer": "There are 5 types of bonds between atoms: metallic bond, ionic bond, covalent bond, physical bond (van der Waals force), hydrogen bond.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举并解释原子间存在的键类型，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查基本概念的记忆和理解，仅需列举原子间键合的类型，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆和识别五种基本化学键的类型，属于基础概念记忆层次。题目不涉及概念解释、比较或复杂分析，仅需简单回忆知识点即可作答，因此属于最低难度等级。", "convertible": true, "correct_option": "5", "choice_question": "How many types of bonds exist between atoms?", "conversion_reason": "The answer is a specific number (5), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3 (ionic, covalent, metallic)", "B": "4 (ionic, covalent, metallic, hydrogen)", "C": "5 (ionic, covalent, metallic, hydrogen, van der Waals)", "D": "6 (ionic, covalent, metallic, hydrogen, van der Waals, dipole-dipole)" }, "correct_answer": "C", "explanation": "The correct answer is C because it includes all five fundamental types of atomic bonds: ionic (electron transfer), covalent (electron sharing), metallic (delocalized electrons), hydrogen (special dipole-dipole), and van der Waals (weak intermolecular). Option A is a common oversimplification that misses hydrogen and van der Waals bonds. Option B correctly adds hydrogen bonds but still omits van der Waals interactions. Option D incorrectly counts dipole-dipole as a separate bond type when it's actually a subtype of van der Waals forces. The difficulty lies in distinguishing between primary bond types and their subtypes, and recognizing hydrogen bonds as a distinct category despite being dipole-dipole in nature.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4736, "question": "The activation energy for the diffusion of copper in silver is 193,000 J/ mol. Calculate the diffusion coefficient at 1200 K\\left(927^{\\circ} C\\right), given that D at 1000 K\\left(727^{\\circ} C\\right) is 1.0 × 10^{-14}{m}^{2} / s.", "answer": "the diffusion coefficient at 1200k is 4.8 × 10^{-13}{m}^{2} / s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的激活能和扩散系数数据，应用阿伦尼乌斯方程进行数值计算，以求解在特定温度下的扩散系数。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用阿伦尼乌斯公式进行多步计算，涉及扩散系数与温度的关系，需要理解活化能的概念并进行数值计算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解扩散系数的概念，掌握阿伦尼乌斯方程的应用，并进行多步骤的计算。题目涉及温度转换、对数运算和指数计算，要求考生能够综合运用这些知识来解决问题。虽然题目提供了部分已知条件，但解题过程仍然需要一定的综合分析能力。", "convertible": true, "correct_option": "4.8 × 10^{-13} m^2/s", "choice_question": "The activation energy for the diffusion of copper in silver is 193,000 J/mol. Given that the diffusion coefficient (D) at 1000 K is 1.0 × 10^{-14} m^2/s, calculate the diffusion coefficient at 1200 K:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.8 × 10^{-13} m^2/s", "B": "1.0 × 10^{-13} m^2/s", "C": "1.9 × 10^{-14} m^2/s", "D": "3.2 × 10^{-12} m^2/s" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Arrhenius equation for diffusion coefficients at different temperatures. Option B is designed to exploit the common mistake of linear extrapolation of temperature effects. Option C targets the misconception that diffusion coefficients change minimally with temperature. Option D is based on the error of overestimating the exponential temperature dependence by using an incorrect pre-exponential factor.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3206, "question": "A Cu-30%Zn brass cold-rolled sheet undergoes 25% cold deformation, resulting in a thickness of 1cm. Find the original thickness Lo.", "answer": "From (Lo - 1)/Lo = 25%, solving gives Lo = 4/3 cm ≈ 1.333 cm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解原始厚度Lo，答案是通过数学计算得出的具体数值结果。 | 知识层次: 题目仅涉及基本的百分比变形计算和简单代数运算，属于直接套用公式和基本计算的应用层次，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算，即通过给定的变形百分比和最终厚度求解原始厚度。解题步骤简单，仅需一步代数运算即可得出答案，无需组合多个公式或进行复杂分析。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "4/3 cm ≈ 1.333 cm", "choice_question": "A Cu-30%Zn brass cold-rolled sheet undergoes 25% cold deformation, resulting in a thickness of 1cm. What was the original thickness Lo?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4/3 cm (1.333 cm)", "B": "1.25 cm", "C": "1.429 cm", "D": "1.667 cm" }, "correct_answer": "A", "explanation": "The correct calculation uses the cold deformation formula: Lf = Lo*(1-deformation). For 25% deformation and Lf=1cm, Lo=1/(1-0.25)=4/3 cm. Option B is a common error from incorrectly calculating 1cm + 25%. Option C results from misapplying the deformation as a thickness reduction ratio (1/0.7). Option D comes from confusing the deformation percentage (using 40% instead of 25%).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4607, "question": "Do all atoms have a net magnetic moment? Why or why not?", "answer": "All atoms do not have a net magnetic moment. If an atom has completely filled electron shells or subshells, there will be a cancellation of both orbital and spin magnetic moments.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释为什么不是所有原子都有净磁矩，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对原子磁矩基本概念的理解，涉及电子排布和磁矩抵消的基本原理，属于基础概念记忆和理解范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆（原子磁矩的定义和分类），但正确选项要求考生理解电子排布与磁矩之间的关系，并能解释为什么完全填满的电子壳层会导致磁矩抵消。这需要比单纯记忆定义更深一层的概念解释能力，但不需要进行复杂的体系阐述或多概念综合分析。", "convertible": true, "correct_option": "All atoms do not have a net magnetic moment. If an atom has completely filled electron shells or subshells, there will be a cancellation of both orbital and spin magnetic moments.", "choice_question": "Do all atoms have a net magnetic moment?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit the multiple-choice format by focusing on the main query.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Only atoms with unpaired electrons exhibit a net magnetic moment", "B": "All atoms inherently possess a net magnetic moment due to nuclear spin", "C": "All atoms have a net magnetic moment when placed in an external magnetic field", "D": "Transition metal atoms always have a net magnetic moment regardless of electron configuration" }, "correct_answer": "A", "explanation": "Correct answer A is accurate because net magnetic moments arise from unpaired electron spins. Option B exploits nuclear physics knowledge by suggesting nuclear spin creates atomic magnetism (false for net moment). Option C uses conditional truth (external fields induce moments) to imply universal truth. Option D leverages the strong association between transition metals and magnetism while ignoring filled subshell cases like Zn2+.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 568, "question": "Given the diffusion constant of carbon in γ-Fe D0=2.0×10^-5m^2/s and the diffusion activation energy Q=140×10^3J/mol, calculate the diffusion coefficient of carbon in γ-Fe at 870℃.", "answer": "The diffusion coefficient of carbon in γ-Fe at 870℃: 7.94×10^-12m^2/s", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的扩散常数和扩散激活能，应用阿伦尼乌斯公式计算特定温度下的扩散系数，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要考查对扩散系数公式的直接应用和简单计算，涉及基本公式的套用和单位转换，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要套用阿伦尼乌斯公式（D = D0 * exp(-Q/RT)），但计算步骤相对直接，仅涉及温度转换（℃转K）和简单的指数运算。不需要多个公式组合或复杂推导，符合等级2的标准。", "convertible": true, "correct_option": "7.94×10^-12m^2/s", "choice_question": "Given the diffusion constant of carbon in γ-Fe D0=2.0×10^-5m^2/s and the diffusion activation energy Q=140×10^3J/mol, the diffusion coefficient of carbon in γ-Fe at 870℃ is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.94×10^-12 m^2/s", "B": "1.58×10^-11 m^2/s", "C": "3.16×10^-5 m^2/s", "D": "2.0×10^-5 m^2/s" }, "correct_answer": "A", "explanation": "正确答案A是通过Arrhenius方程D=D0*exp(-Q/RT)精确计算得出。干扰项B是未将温度转换为开尔文导致的错误结果；干扰项C错误地忽略了指数项，直接使用了D0值；干扰项D是完全忽略温度影响的常见认知偏差，直接采用室温下的扩散常数。这些干扰项利用了材料科学计算中常见的单位转换错误和公式应用不完整等典型错误模式。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1809, "question": "In the non-stoichiometric compound Cd1+xO, the type of non-stoichiometric structural defect present is a. anion vacancy b. cation vacancy c. anion interstitial d. cation interstitial", "answer": "d", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从四个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查非化学计量化合物中缺陷类型的基本概念记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念记忆层次，要求考生识别非化学计量化合物Cd1+xO中的缺陷类型。虽然涉及特定缺陷类型的记忆（阳离子间隙），但不需要复杂的分析或概念间的比较，属于概念理解和简单辨析的难度等级。", "convertible": true, "correct_option": "d. cation interstitial", "choice_question": "In the non-stoichiometric compound Cd1+xO, the type of non-stoichiometric structural defect present is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Schottky defect", "B": "Frenkel defect", "C": "Metal excess defect due to anion vacancies", "D": "Metal deficiency defect due to cation vacancies" }, "correct_answer": "C", "explanation": "In Cd1+xO, the excess cadmium (Cd) occupies interstitial positions, creating a metal excess defect. This is compensated by the formation of anion (oxygen) vacancies to maintain charge neutrality. The correct defect type is therefore metal excess due to anion vacancies (Option C). The distractors exploit common misconceptions: A) Schottky defects involve paired cation-anion vacancies, which doesn't apply here; B) Frenkel defects involve cation displacement to interstitial sites, but without the stoichiometric excess; D) suggests the opposite type of non-stoichiometry, which is a common error when interpreting the formula notation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 684, "question": "The symmetry characteristic of the cubic crystal system is having four 3-fold axes", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（立方晶系的对称性特征是具有四个三重轴），并要求判断其正确性（√表示正确），这是典型的判断题形式 | 知识层次: 题目考查立方晶系对称性特征的基础概念记忆，仅需判断\"四个三次轴\"这一基本特征的正确性，属于定义性知识的直接应用。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅要求判断立方晶系的对称性特征是否正确，即是否具有四个三重轴。这属于基础概念的记忆性知识，不需要深入理解或分析多个概念。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "√", "choice_question": "The symmetry characteristic of the cubic crystal system is having four 3-fold axes", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials will eventually crystallize given sufficient time under ambient conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many amorphous materials can crystallize over time, some (like certain oxide glasses) are thermodynamically stable in their amorphous state under ambient conditions. The absolute term 'all' makes this statement false. This tests understanding of kinetic vs thermodynamic stability in amorphous materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4740, "question": "Carbon dioxide diffuses through a high-density polyethylene (HDPE) sheet 50mm thick at a rate of 2.2 × 10^{-8}\\left(cm^{3} STP / {cm}^{2}\\right.-s at 325 K. The pressures of carbon dioxide at the two faces are 4000 kPa and 2500 kPa, which are maintained constant. Assuming conditions of steady state, what is the permeability coefficient at 325 K ?", "answer": "the permeability coefficient at 325k is 0.73 × 10^{-13} \\frac{{cm}^{3} \\mathrm{stp}·{cm}}{{cm}^{2}·s·\\mathrm{pa}}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解渗透系数，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括应用扩散定律和稳态条件，涉及压力差和厚度的综合分析，需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散速率、压力差和渗透系数的关系，并进行多步计算。题目涉及稳态条件下的渗透系数计算，需要综合应用菲克定律和渗透系数的定义，属于综合性计算问题。虽然计算步骤明确，但需要正确关联概念和单位转换，对学生的理解能力和计算能力有一定要求。", "convertible": true, "correct_option": "0.73 × 10^{-13} \\frac{{cm}^{3} \\mathrm{stp}·{cm}}{{cm}^{2}·s·\\mathrm{pa}}", "choice_question": "Carbon dioxide diffuses through a high-density polyethylene (HDPE) sheet 50mm thick at a rate of 2.2 × 10^{-8}\\left(cm^{3} STP / {cm}^{2}\\right.-s at 325 K. The pressures of carbon dioxide at the two faces are 4000 kPa and 2500 kPa, which are maintained constant. Assuming conditions of steady state, what is the permeability coefficient at 325 K?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "0.73 × 10^{-13} \\frac{{cm}^{3} \\mathrm{stp}·{cm}}{{cm}^{2}·s·\\mathrm{pa}}", "C": "选项B", "D": "选项D" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1612, "question": "What are the formation and movement characteristics of Frank partial dislocations in face-centered cubic crystals?", "answer": "Frank partial dislocations are caused by the removal or insertion of a close-packed plane, and their Burgers vector is perpendicular to the slip plane. Therefore, Frank partial dislocations cannot glide but can only climb.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Frank partial dislocations的形成和运动特性，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释Frank不全位错的形成和运动特性，涉及位错的形成机制、Burgers向量的方向性以及位错滑移和攀移的区别。这需要综合运用位错理论、晶体结构知识以及位错运动的机理分析，属于较高层次的认知能力要求。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Frank partial dislocations are caused by the removal or insertion of a close-packed plane, and their Burgers vector is perpendicular to the slip plane. Therefore, Frank partial dislocations cannot glide but can only climb.", "choice_question": "Which of the following correctly describes the formation and movement characteristics of Frank partial dislocations in face-centered cubic crystals?", "conversion_reason": "The answer is a standard description of the concept, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Frank partial dislocations are caused by the removal or insertion of a close-packed plane, and their Burgers vector is perpendicular to the slip plane. Therefore, Frank partial dislocations cannot glide but can only climb.", "B": "Frank partial dislocations result from shear deformation, with Burgers vectors parallel to the slip plane, enabling them to glide easily through the crystal lattice.", "C": "Frank partial dislocations form through vacancy condensation, with Burgers vectors at 60° to the slip plane, allowing both glide and climb mechanisms.", "D": "Frank partial dislocations originate from impurity segregation, with Burgers vectors perpendicular to the slip plane, but can still glide through thermal activation." }, "correct_answer": "A", "explanation": "The correct answer is A because Frank partial dislocations are indeed formed by the removal or insertion of a close-packed plane, and their Burgers vector is perpendicular to the slip plane, preventing glide and limiting movement to climb. Option B is incorrect because it describes characteristics of Shockley partial dislocations, not Frank partial dislocations. Option C is misleading as it mixes correct formation mechanism with incorrect Burgers vector orientation and movement capability. Option D introduces an entirely wrong formation mechanism while partially correct about Burgers vector orientation, creating a sophisticated trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2925, "question": "After quenching, 1.2% steel obtains a martensite and a small amount of retained austenite structure. What changes will occur when heated to 680°C and held for 2 hours?", "answer": "Carbides are distributed in granular form within the ferrite matrix, resulting in a granular pearlite structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释材料在特定热处理条件下的结构变化，答案提供了详细的文字描述，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求分析淬火后钢在特定热处理条件下的组织转变，涉及多个概念（马氏体、残余奥氏体、回火过程）的关联和综合分析，需要理解热处理工艺对材料微观结构的影响机制，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合理解淬火后的组织转变、回火过程中的相变行为以及最终组织的形成机制。题目要求考生将多个热处理概念（马氏体、残余奥氏体、碳化物析出、粒状珠光体形成）进行关联分析，并预测特定工艺参数（680°C保温2小时）下的微观组织演变。这超出了简单记忆的范畴，需要进行多步骤的逻辑推理和综合判断。", "convertible": true, "correct_option": "Carbides are distributed in granular form within the ferrite matrix, resulting in a granular pearlite structure.", "choice_question": "After quenching, 1.2% steel obtains a martensite and a small amount of retained austenite structure. What changes will occur when heated to 680°C and held for 2 hours?", "conversion_reason": "The answer is a standard description of a metallurgical process, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": "None", "perplexity_level": "None", "perplexity_reason": "None", "missing_info": "None" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Carbides are distributed in granular form within the ferrite matrix, resulting in a granular pearlite structure", "B": "The retained austenite transforms into fresh martensite due to thermal activation", "C": "A fully spheroidized cementite structure forms in a ferrite matrix", "D": "The structure remains largely unchanged as this temperature is below Ac1" }, "correct_answer": "A", "explanation": "The correct answer is A because at 680°C (below Ac1 but within tempering range), the martensite decomposes into ferrite with dispersed carbides forming granular pearlite. Option B is incorrect because fresh martensite only forms during rapid cooling, not heating. Option C is a trap for those who confuse tempering with full spheroidization which requires longer times/higher temps. Option D exploits the common misconception that subcritical temperatures cause no microstructural changes, ignoring tempering effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3599, "question": "Gallium has an orthorhombic structure, with a0=0.45258 nm, b0=0.45186 nm, and c0=0.76570 nm. The atomic radius is 0.1218 nm. The density is 5.904 g/cm3 and the atomic weight is 69.72 g/mol. Determine the packing factor in the unit cell.", "answer": "0.387.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（如计算晶胞的堆积因子）来得出具体数值答案（0.387），属于典型的计算题特征。 | 知识层次: 题目需要进行多步计算，包括晶胞体积、原子体积和堆积因子的计算，涉及多个参数的关联和综合分析，需要理解和应用晶体结构的基本原理和公式。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、原子半径、密度和原子重量等多个概念，并进行多步计算（包括晶胞体积、原子体积、原子数等）才能得出正确的堆积因子。虽然题目提供了所有必要数据，但解题步骤较为复杂，需要综合分析和准确计算。", "convertible": true, "correct_option": "0.387", "choice_question": "Gallium has an orthorhombic structure, with a0=0.45258 nm, b0=0.45186 nm, and c0=0.76570 nm. The atomic radius is 0.1218 nm. The density is 5.904 g/cm3 and the atomic weight is 69.72 g/mol. Determine the packing factor in the unit cell.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion to a multiple-choice format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.387", "B": "0.452", "C": "0.521", "D": "0.612" }, "correct_answer": "A", "explanation": "正确答案0.387是通过计算单位晶胞体积(a0×b0×c0)和原子体积(4/3πr³×原子数)得出的精确值。干扰项B(0.452)利用了晶格参数a0的数值迷惑，干扰项C(0.521)基于简单立方结构的典型值设置陷阱，干扰项D(0.612)则采用了面心立方结构的理论最大值作为误导。这些干扰项都利用了材料科学中常见结构的典型值来制造认知偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 588, "question": "What is the deformation process of polycrystalline metals?", "answer": "In the deformation process of polycrystalline metals, the deformation of each grain is mainly through slip, and may also involve twinning and kinking. Multiple slip systems need to be activated, leading to cross-slip. Due to the influence of grain boundaries, there are also effects of orientation difference and the blocking effect of grain boundaries.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释多晶金属的变形过程，答案提供了详细的文字解释和论述，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目要求解释多晶金属的变形过程，涉及多种变形机制（滑移、孪生、扭折）的相互作用，以及晶界效应和取向差的影响。这需要对材料变形机理有深入理解，并能综合分析不同因素间的关联，属于机理层面的复杂分析。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "In the deformation process of polycrystalline metals, the deformation of each grain is mainly through slip, and may also involve twinning and kinking. Multiple slip systems need to be activated, leading to cross-slip. Due to the influence of grain boundaries, there are also effects of orientation difference and the blocking effect of grain boundaries.", "choice_question": "Which of the following best describes the deformation process of polycrystalline metals?", "conversion_reason": "The answer is a standard description of the deformation process of polycrystalline metals, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Deformation occurs primarily through dislocation glide within grains, with grain boundaries acting as barriers that require activation of multiple slip systems", "B": "Deformation is dominated by grain boundary sliding at room temperature, with minimal contribution from intragranular dislocation motion", "C": "Plastic deformation proceeds via stress-induced phase transformation, where grains collectively transform to a higher symmetry crystal structure", "D": "The Hall-Petch relationship governs deformation through grain boundary diffusion, with finer grains deforming more easily than coarse grains" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual deformation mechanism where dislocations glide on slip planes within grains, requiring activation of multiple slip systems due to grain boundary constraints. Option B is incorrect because grain boundary sliding is significant only at high temperatures. Option C incorrectly suggests phase transformation as the primary mechanism, which is rare in typical polycrystalline metals. Option D misapplies the Hall-Petch relationship, which actually predicts stronger materials with finer grains due to dislocation pile-up effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3495, "question": "What measures should be taken to improve the strength of stainless steel?", "answer": "Measures: Work hardening. Some martensitic stainless steels (such as 4Cr13) can be strengthened through heat treatment (quenching + low-temperature tempering).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释如何提高不锈钢的强度，答案提供了文字解释和论述，没有选项、对错判断或数值计算的需求。 | 知识层次: 题目要求回答提高不锈钢强度的措施，涉及工作硬化和热处理（淬火+低温回火）等具体工艺的应用。需要理解不同不锈钢类型（如马氏体不锈钢4Cr13）的特性及其强化机制，属于多概念关联和综合分析的应用层次。 | 难度: 在选择题中属于中等难度，题目要求理解不锈钢强化的具体措施（加工硬化和热处理），并需要关联不同种类不锈钢（如马氏体不锈钢4Cr13）的特定强化方法。虽然不涉及复杂计算，但需要对材料强化机制和热处理工艺有综合理解，属于概念关联和综合分析层次。", "convertible": true, "correct_option": "Work hardening. Some martensitic stainless steels (such as 4Cr13) can be strengthened through heat treatment (quenching + low-temperature tempering).", "choice_question": "Which of the following measures can be taken to improve the strength of stainless steel?", "conversion_reason": "The answer is a standard and specific set of measures, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Work hardening combined with low-temperature tempering for martensitic grades", "B": "Increasing chromium content above 20% to enhance dislocation mobility", "C": "Solution annealing at 1100°C followed by rapid quenching for all types", "D": "Applying grain growth inhibitors to maintain small grain size in austenitic steels" }, "correct_answer": "A", "explanation": "Correct answer A combines two valid strengthening mechanisms specific to martensitic stainless steels. Option B exploits the common misconception that higher chromium always improves strength, while actually reducing work hardening capacity. Option C uses a real heat treatment but incorrectly applies it universally. Option D sounds plausible but grain growth inhibitors are ineffective for austenitic steels' inherent low stacking fault energy.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4175, "question": "Relative to electrons and electron states, what does the ms quantum number specify?", "answer": "The ms quantum number designates the spin moment on each electron.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释ms量子数的含义，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对量子数ms的基本定义和概念的记忆，属于基础概念记忆层次，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅考察对ms量子数定义的基本记忆，属于最基础的概念性知识。正确选项直接给出了定义，不需要任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The ms quantum number designates the spin moment on each electron.", "choice_question": "Relative to electrons and electron states, what does the ms quantum number specify?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The spin moment on each electron", "B": "The principal energy level of the electron", "C": "The orbital angular momentum of the electron", "D": "The magnetic quantum number projection" }, "correct_answer": "A", "explanation": "The correct answer is A because ms specifically denotes the spin quantum number (+1/2 or -1/2) representing the electron's intrinsic spin. Option B is incorrect but tempting as it relates to the principal quantum number n. Option C is a common confusion with the l quantum number for orbital shape. Option D mimics the ml quantum number for orbital orientation, creating a subtle naming trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4078, "question": "[c] Tantalum offers extremely good corrosion resistance, especially at low temperatures.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（Tantalum offers extremely good corrosion resistance, especially at low temperatures），并要求判断其正确性（答案：T），符合判断题的特征。 | 知识层次: 题目考查对钽（Tantalum）腐蚀抗性这一基本特性的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆钽(Tantalum)具有良好耐腐蚀性的特性，尤其是低温环境下的表现。题目不涉及概念理解或复杂分析，仅需基础概念记忆即可正确作答，因此属于最低难度等级。", "convertible": true, "correct_option": "T", "choice_question": "[c] Tantalum offers extremely good corrosion resistance, especially at low temperatures.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit higher hardness than metallic materials at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics are harder than metals, this is not universally true. Some metallic materials like hardened tool steels can surpass the hardness of certain ceramics. The absolute term 'all' makes this statement false. Additionally, hardness depends on microstructure and processing conditions, not just material class.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 486, "question": "The finer the grain size, the higher the strength and hardness of the crystal, and the better the plasticity and toughness.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对晶粒尺寸与材料力学性能关系的基本概念记忆，属于材料科学中最基础的知识点之一，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆晶粒尺寸与材料性能的基本关系即可作答，无需深入理解或分析多个概念。", "convertible": true, "correct_option": "√", "choice_question": "The finer the grain size, the higher the strength and hardness of the crystal, and the better the plasticity and toughness.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "According to the Hall-Petch relationship, reducing grain size always leads to simultaneous improvement in both strength and ductility for all crystalline materials.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the Hall-Petch relationship generally holds that finer grain size increases strength, the effect on ductility is more complex. For many materials, reducing grain size below a certain critical size can actually decrease ductility due to limited dislocation activity. Additionally, some amorphous materials don't follow this relationship. The use of 'always' and 'all' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4751, "question": "Why is copper not considered for the cylindrical rod subjected to a tensile load of 29,000 N (6500 lb) with a maximum allowed elongation of 1.3mm (0.05 in.)?", "answer": "Copper is not considered due to its lower yield strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么铜不被考虑用于特定应用场景，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目需要理解铜的力学性能（如屈服强度）与具体工程应用（如承受拉伸载荷和允许伸长量）之间的关系，并进行综合分析判断。这涉及多步思考和概念关联，超出了简单记忆或直接套用的层次，但尚未达到复杂分析或高级综合的深度。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及对材料性能（如屈服强度）的理解，以及如何将其应用于具体工程场景（如拉伸载荷下的伸长限制）。虽然题目提供了具体数值，但正确选项要求考生能够将铜的力学性能与题目要求进行关联分析，而不是简单的记忆或单一概念的应用。这需要中等层次的应用能力和综合分析能力。", "convertible": true, "correct_option": "Copper is not considered due to its lower yield strength.", "choice_question": "Why is copper not considered for the cylindrical rod subjected to a tensile load of 29,000 N (6500 lb) with a maximum allowed elongation of 1.3mm (0.05 in.)?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Copper's elastic modulus is too low to prevent excessive elongation", "B": "Copper's yield strength is insufficient to withstand the applied stress", "C": "Copper's FCC structure causes excessive dislocation movement under load", "D": "Copper's high thermal conductivity leads to premature failure" }, "correct_answer": "B", "explanation": "The correct answer is B because copper's relatively low yield strength (typically 70-300 MPa) makes it prone to plastic deformation under the given load. Option A is a cognitive bias trap - while elongation is mentioned, the elastic modulus (110-130 GPa) is actually sufficient. Option C exploits material science intuition about FCC structures but is irrelevant here. Option D introduces a plausible-sounding but unrelated thermal property distraction.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2714, "question": "The vacancy formation energy (E_v) and interstitial atom formation energy (E_i) of Al are 0.76 eV and 3.0 eV, respectively. Calculate the ratio of the equilibrium concentration of vacancies to the equilibrium concentration of interstitial atoms in Al at 500°C.", "answer": "At 500°C: C_V/C_i = e^((1/(8.617×10^-5×773))(3.0-0.76)) = e^33.63 = 4.026×10^14", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及能量和浓度的计算，答案也是通过具体计算得出的数值结果。 | 知识层次: 题目需要应用缺陷形成能的基本概念，进行多步计算（包括温度转换、玻尔兹曼因子计算和指数运算），并理解平衡浓度与形成能之间的关系。虽然不涉及复杂的机理分析或创新设计，但需要综合运用多个知识点进行计算和结果解释。 | 难度: 在选择题中属于中等偏上难度，需要理解空位形成能和间隙原子形成能的概念，掌握平衡浓度计算公式，并能正确进行多步指数运算。题目涉及温度单位转换（°C转K）、玻尔兹曼常数应用以及综合计算能力，但选项提供了明确的解题路径，减少了部分分析难度。", "convertible": true, "correct_option": "4.026×10^14", "choice_question": "The vacancy formation energy (E_v) and interstitial atom formation energy (E_i) of Al are 0.76 eV and 3.0 eV, respectively. What is the ratio of the equilibrium concentration of vacancies to the equilibrium concentration of interstitial atoms in Al at 500°C?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.026×10^14", "B": "2.463×10^7", "C": "1.642×10^21", "D": "6.314×10^12" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Arrhenius equation for defect concentrations: ratio = exp((E_i - E_v)/kT). At 500°C (773K), with k=8.617×10^-5 eV/K, this gives exp((3.0-0.76)/(8.617×10^-5×773))=4.026×10^14. Option B results from incorrectly using the formation energy difference in the denominator. Option C comes from miscalculating the temperature in Kelvin. Option D arises from swapping the formation energies in the calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1210, "question": "What is the equilibrium distribution coefficient?", "answer": "Equilibrium distribution coefficient: During the crystallization of solid solution alloys, selective crystallization occurs. Therefore, under equilibrium conditions at a certain temperature, the ratio of the solid phase composition to the liquid phase composition is called the equilibrium distribution coefficient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"equilibrium distribution coefficient\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征 | 知识层次: 题目考查基本概念的记忆和理解，即平衡分布系数的定义和基本原理，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆\"平衡分配系数\"的定义，即在一定温度下固相组成与液相组成的比值。虽然涉及专业术语，但只需直接回忆定义内容，无需进行复杂的概念体系阐述或比较分析。在选择题型内，这属于中等偏下的难度，主要考察基础概念的记忆能力。", "convertible": true, "correct_option": "Equilibrium distribution coefficient: During the crystallization of solid solution alloys, selective crystallization occurs. Therefore, under equilibrium conditions at a certain temperature, the ratio of the solid phase composition to the liquid phase composition is called the equilibrium distribution coefficient.", "choice_question": "Which of the following best describes the equilibrium distribution coefficient?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ratio of solid phase composition to liquid phase composition at equilibrium during solidification of solid solution alloys", "B": "The ratio of diffusion coefficients between solute atoms in solid and liquid phases at eutectic temperature", "C": "The ratio of elastic modulus to shear modulus in a two-phase composite material", "D": "The ratio of solid solubility limits at two different temperatures in a phase diagram" }, "correct_answer": "A", "explanation": "The correct answer is A because the equilibrium distribution coefficient specifically refers to the ratio of compositions in solid and liquid phases during solidification of solid solution alloys under equilibrium conditions. Option B is a cognitive bias trap, confusing distribution coefficient with diffusion phenomena at eutectic points. Option C exploits material property confusion by mixing mechanical properties with phase equilibrium concepts. Option D creates a professional intuition trap by referencing real phase diagram concepts but applying them incorrectly to the definition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1411, "question": "What type of diffusion does the homogenization of intracrystalline segregation during diffusion annealing belong to?", "answer": "The homogenization of intracrystalline segregation during diffusion annealing belongs to interdiffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对扩散退火过程中晶内偏析的均匀化类型进行解释，答案需要文字论述而非选择、判断或计算 | 知识层次: 题目考查扩散类型的基本概念记忆和理解，属于对基础分类知识的直接问答 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即对\"interdiffusion\"这一术语的定义和分类的直接回忆。题目不需要解释或描述概念，更不需要分析复杂概念体系，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "interdiffusion", "choice_question": "What type of diffusion does the homogenization of intracrystalline segregation during diffusion annealing belong to?", "conversion_reason": "The answer is a standard term (interdiffusion), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "interdiffusion", "B": "self-diffusion", "C": "vacancy diffusion", "D": "grain boundary diffusion" }, "correct_answer": "A", "explanation": "The correct answer is interdiffusion because homogenization of intracrystalline segregation involves the redistribution of different atomic species to achieve uniform composition. Self-diffusion (B) is incorrect as it refers to movement of identical atoms. Vacancy diffusion (C) is a mechanism not a type, and grain boundary diffusion (D) is incorrect as the process occurs within crystals not along boundaries. The distractors exploit common confusion between diffusion mechanisms and types, and the intuitive but incorrect association of segregation with grain boundaries.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2165, "question": "Calculate the interparticle spacing λ, given the number of Fe3C particles per unit volume NV=1.43×1013", "answer": "λ=NV-1/3=(1.43×1013)-1/3=0.24×10-5m=2.4μm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算interparticle spacing λ），并给出了具体的计算公式和步骤，最终需要得出一个具体的数值结果。 | 知识层次: 题目仅涉及基本公式的直接套用和简单计算，不需要多步推理或综合分析，属于简单应用层次。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（NV-1/3）进行计算，无需额外的概念理解或步骤组合。属于最基础的难度等级，仅需基本公式应用和简单计算能力。", "convertible": true, "correct_option": "2.4μm", "choice_question": "Calculate the interparticle spacing λ, given the number of Fe3C particles per unit volume NV=1.43×10^13.", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a single-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.4μm", "B": "1.7μm", "C": "3.1nm", "D": "4.2×10^-6 m" }, "correct_answer": "A", "explanation": "The correct answer is A (2.4μm) calculated using λ = (1/NV)^(1/3). Option B (1.7μm) exploits cognitive bias by providing a value close to the correct answer but derived from incorrect cube root calculation. Option C (3.1nm) is a professional intuition trap using realistic nanoscale spacing values that don't apply to this Fe3C system. Option D (4.2×10^-6 m) is a unit conversion trap that appears dimensionally correct but represents an incorrect calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1949, "question": "It is known that for a certain crystal at 500°C, 1 vacancy can form for every 10^10 atoms. What is the vacancy formation energy of this crystal? (Given: the constant A=0.0539 for this crystal, Boltzmann constant k=1.381×10^-23 J/K)", "answer": "$$ x\\\\begin{array}{c}{{c=A\\\\exp\\\\enspace\\\\big(\\\\enspace-\\\\frac{\\\\Delta E_{V}}{k T}\\\\big)}}\\\\ {{\\\\Delta E_{V}=-k T\\\\mathrm{ln}\\\\frac{c}{A}=\\\\mathrm{-\\\\enspace\\\\left[1.381\\\\times10^{-23}\\\\times\\\\enspace\\\\left(500+273\\\\right)\\\\right]\\\\enspace\\\\mathrm{ln}\\\\frac{10^{-10}}{0.0539}\\\\mathrm{\\\\scriptsize\\\\mathrm{~J}}}}}\\\\\\\\ {{=1.068\\\\times10^{-20}\\\\times17.8=1.9\\\\times10^{-19}\\\\mathrm{\\\\scriptsize{\\\\times10^{-19}}}}}\\\\\\\\ \\n $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和数据进行数值计算，最终得出空缺形成能的具体数值。答案展示了详细的推导过程和计算结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和公式应用，需要理解空位形成能的概念，并能够正确应用玻尔兹曼方程进行计算。虽然计算过程较为直接，但需要将多个概念（如浓度、温度、能量）关联起来，并进行对数运算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解空位形成能的概念，掌握相关公式，并进行多步计算。题目涉及对数运算、单位转换和常数代入，要求考生具备较强的综合计算能力和概念关联能力。虽然题目提供了公式和常数，但计算过程较为复杂，需要仔细推导和验证。", "convertible": true, "correct_option": "1.9×10^-19 J", "choice_question": "It is known that for a certain crystal at 500°C, 1 vacancy can form for every 10^10 atoms. What is the vacancy formation energy of this crystal? (Given: the constant A=0.0539 for this crystal, Boltzmann constant k=1.381×10^-23 J/K)", "conversion_reason": "The calculation question has a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.9×10^-19 J", "B": "3.8×10^-19 J", "C": "9.5×10^-20 J", "D": "2.4×10^-19 J" }, "correct_answer": "A", "explanation": "The correct answer is derived from the Arrhenius-type equation for vacancy concentration: n/N = A*exp(-E_v/kT). Solving for E_v gives the correct value. Option B doubles the correct value, exploiting a common calculation error. Option C is half the correct value, targeting those who misplace the decimal. Option D is derived by incorrectly using 300K instead of 773K, a temperature unit conversion trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4801, "question": "A large plate is fabricated from a steel alloy that has a plane strain fracture toughness of 82.4 MPa \\sqrt{m}(75.0 ksi \\sqrt{m}.). If the plate is exposed to a tensile stress of 345 MPa(50,000 psi) during service use, determine the minimum length of a surface crack that will lead to fracture. Assume a value of 1.0 for Y.", "answer": "the minimum length of a surface crack that will lead to fracture is 0.0182 \\text{ m} (18.2 mm).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（使用平面应变断裂韧性公式）来确定表面裂纹的最小长度，答案是一个具体的数值结果。 | 知识层次: 题目需要应用平面应变断裂韧性公式进行多步计算，涉及应力强度因子与裂纹长度的关系，并需要综合分析给定条件（如Y值假设）来求解最小裂纹长度。虽然公式直接给出，但需要理解各参数意义并进行正确代入计算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解断裂力学的基本概念（如平面应变断裂韧性、应力强度因子等），并能够正确应用相关公式进行多步骤计算。题目要求考生能够将理论知识与实际应用相结合，综合分析给定条件并得出正确结论。虽然题目提供了所有必要参数，但解题过程涉及多个步骤和概念关联，对考生的综合能力有一定要求。", "convertible": true, "correct_option": "0.0182 m (18.2 mm)", "choice_question": "A large plate is fabricated from a steel alloy that has a plane strain fracture toughness of 82.4 MPa √m (75.0 ksi √m). If the plate is exposed to a tensile stress of 345 MPa (50,000 psi) during service use, determine the minimum length of a surface crack that will lead to fracture. Assume a value of 1.0 for Y.", "conversion_reason": "The calculation question has a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0182 m", "B": "0.0085 m", "C": "0.0364 m", "D": "0.0046 m" }, "correct_answer": "A", "explanation": "正确答案A是通过断裂力学公式K_IC=Yσ√(πa)计算得出，其中K_IC=82.4 MPa√m, σ=345 MPa, Y=1.0。干扰项B是通过错误地将应力值减半计算得出，利用了认知偏差。干扰项C是正确答案的两倍，利用了单位换算的直觉陷阱。干扰项D是通过错误地使用剪切模量而非断裂韧性计算得出，属于专业直觉陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1294, "question": "What does recrystallization conceptually refer to as a process?", "answer": "Recrystallization refers to the process in which a substance transforms from one structure to another in the solid state, i.e., an allotropic transformation reaction.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对recrystallization的概念进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对再结晶这一基本概念的定义和简单解释，属于基础概念记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求对\"recrystallization\"这一基础概念的定义进行记忆性回答，属于最基本的概念简答。题目仅涉及单一概念的定义，不需要进行解释或比较分析，解题步骤简单直接，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Recrystallization refers to the process in which a substance transforms from one structure to another in the solid state, i.e., an allotropic transformation reaction.", "choice_question": "What does recrystallization conceptually refer to as a process?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The formation of new strain-free grains from deformed material during annealing", "B": "The phase transformation from amorphous to crystalline structure", "C": "The dissolution and reprecipitation of a substance to purify it", "D": "The rearrangement of dislocations into low-energy configurations" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines recrystallization in materials science as the replacement of deformed grains with new, strain-free grains during annealing. Option B is incorrect because it describes crystallization, not recrystallization - a common confusion. Option C is a chemistry definition of recrystallization, exploiting interdisciplinary terminology overlap. Option D describes recovery, a related but distinct process, targeting those who confuse similar metallurgical phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4522, "question": "Estimate the maximum thermal conductivity value for a cermet that contains 85 vol % titanium carbide (TiC) particles in a cobalt matrix. Assume thermal conductivities of 27 and 69 W/m-K for TiC and Co, respectively.", "answer": "the maximum thermal conductivity k_max is 33.3 W/m-K.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计最大热导率值，答案是一个具体的数值结果，解答过程需要运用材料科学中的热导率计算原理。 | 知识层次: 题目需要进行多步计算，涉及复合材料热导率的估算，需要理解并应用复合材料热导率的最大值计算公式，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解复合材料热导率的混合规则（如串联模型），并正确应用体积分数进行计算。题目涉及两个材料参数的整合和多步骤计算，但选项已经给出了具体数值，减少了部分推导难度。", "convertible": true, "correct_option": "33.3 W/m-K", "choice_question": "Estimate the maximum thermal conductivity value for a cermet that contains 85 vol % titanium carbide (TiC) particles in a cobalt matrix. Assume thermal conductivities of 27 and 69 W/m-K for TiC and Co, respectively.", "conversion_reason": "The calculation question has a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "33.3 W/m-K", "B": "58.2 W/m-K", "C": "27.0 W/m-K", "D": "42.7 W/m-K" }, "correct_answer": "A", "explanation": "The correct answer is A (33.3 W/m-K) calculated using the inverse rule of mixtures for maximum thermal conductivity in particulate composites. Option B (58.2 W/m-K) is a cognitive bias trap using simple rule of mixtures which overestimates conductivity. Option C (27.0 W/m-K) exploits the intuition that high particle content would dominate, ignoring matrix contribution. Option D (42.7 W/m-K) is a multi-level verification trap using geometric mean calculation which is inappropriate for this microstructure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4020, "question": "Complete the following statement regarding conditions that must be satisfied in order for a solid solution to exhibit extensive solubility. The solute and host species must have a very [w] sizes. (w = similar, different)", "answer": "The solute and host species must have a very similar sizes.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的两个选项（similar, different）中选择一个正确答案来填空 | 知识层次: 题目考查对固溶体溶解度条件的基本概念记忆，仅需知道溶质和溶剂原子尺寸相似性这一基本原理即可作答，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于简单概念识别，直接记忆的难度等级。题目仅要求考生回忆并选择正确的定义性知识（\"similar sizes\"），无需进行概念辨析或深度理解。这种类型的题目在选择题中属于最基础的难度级别。", "convertible": true, "correct_option": "similar", "choice_question": "Complete the following statement regarding conditions that must be satisfied in order for a solid solution to exhibit extensive solubility. The solute and host species must have a very [w] sizes.", "conversion_reason": "The original question is already in a multiple-choice format with two options (similar, different), making it convertible to a single-choice question by selecting the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "similar", "B": "identical", "C": "complementary", "D": "compensating" }, "correct_answer": "A", "explanation": "The correct answer is A (similar) because the Hume-Rothery rules state that atomic size difference must be less than 15% for extensive solid solubility. B (identical) is a cognitive bias trap - while perfect size match seems ideal, real materials always have some size variation. C (complementary) exploits metallurgical terminology confusion by suggesting a non-existent size relationship. D (compensating) creates a multi-level verification trap by implying size differences can be offset by other factors, which is only partially true for limited solubility cases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3867, "question": "A steel is heated until 40% austenite, with a carbon content of 0.5%, forms. Estimate the overall carbon content of the steel.", "answer": "the overall carbon content of the steel is 0.212% c.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算来估计钢的总体碳含量，涉及数值计算和公式应用。答案也是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及奥氏体形成比例和碳含量的关系，需要理解相图和相关公式的应用，并进行综合分析得出结果。 | 难度: 在选择题中属于中等偏上难度，需要理解奥氏体形成比例与碳含量的关系，并进行多步计算。题目要求将40%奥氏体（含碳0.5%）与剩余相（假设为铁素体）的碳含量进行综合计算，涉及相图知识和质量平衡概念。虽然选择题提供了正确选项，但仍需进行综合分析才能确认答案，比单纯的概念识别题更复杂。", "convertible": true, "correct_option": "0.212% c", "choice_question": "A steel is heated until 40% austenite, with a carbon content of 0.5%, forms. What is the overall carbon content of the steel?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.212%", "B": "0.300%", "C": "0.500%", "D": "0.125%" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the lever rule: overall carbon content = (0.4 * 0.5%) + (0.6 * 0.02%) = 0.212%. Option B is a cognitive bias trap, representing a simple average of 40% and 0.5%. Option C exploits the intuitive but incorrect assumption that the overall composition equals the austenite composition. Option D is a professional intuition trap, using the carbon content of pure ferrite but ignoring the austenite contribution.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4599, "question": "Briefly explain how the degree of crystallinity affects the thermal conductivity of polymeric materials and why.", "answer": "Increasing the degree of crystallinity of a semicrystalline polymer enhances its thermal conductivity; the vibrations, rotations, etc. of the molecular chains are more effective modes of thermal transport when a crystalline structure prevails.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求简要解释结晶度对聚合物材料热导率的影响及其原因，答案以文字解释和论述的形式呈现，符合简答题的特征。 | 知识层次: 题目要求解释结晶度对聚合物热导率的影响及其原因，涉及概念关联和综合分析，需要理解结晶结构对分子链振动和热传导的影响机制，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解结晶度与热导率之间的关系，并能够解释分子链振动、旋转等行为在晶体结构中对热传导的影响。虽然不涉及多步计算，但需要对概念进行关联和综合分析。", "convertible": true, "correct_option": "Increasing the degree of crystallinity of a semicrystalline polymer enhances its thermal conductivity; the vibrations, rotations, etc. of the molecular chains are more effective modes of thermal transport when a crystalline structure prevails.", "choice_question": "How does the degree of crystallinity affect the thermal conductivity of polymeric materials?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Higher crystallinity increases thermal conductivity by enabling more efficient phonon transport through ordered crystalline regions", "B": "Higher crystallinity decreases thermal conductivity due to increased phonon scattering at amorphous-crystalline interfaces", "C": "Crystallinity has negligible effect on thermal conductivity as it primarily affects mechanical properties", "D": "Thermal conductivity first increases then decreases with crystallinity due to competing effects of chain alignment and defect formation" }, "correct_answer": "A", "explanation": "The correct answer is A because crystalline regions in polymers provide more ordered pathways for phonon transport, enhancing thermal conductivity. Option B is a cognitive bias trap - while interfaces do scatter phonons, the overall effect of increased crystallinity dominates. Option C exploits incorrect intuition about property isolation. Option D creates a multi-variable verification trap by introducing a non-monotonic relationship that doesn't apply to most semicrystalline polymers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2483, "question": "The subgrain boundaries formed after polygonization contain π edge dislocations, and the misorientation between subgrains is 10^-3 radians. Assuming there is no interaction between dislocations before polygonization, how much energy is released after polygonization (expressed as a percentage)? (The grain boundary energy E⊥-E0θ(A-1)=β, where A is set to 0.5)", "answer": "Before polygonization, the dislocations have no interaction, meaning their energy is the same as when they exist independently. Assuming the dislocations are edge dislocations, the total energy E1 of these π dislocations when they exist separately is πEe, where Ee is the energy per unit length of an edge dislocation: Ee = (μb^2)/(4π(1-ν)) ln(R/r0) ≈ 10θ E0, where E0 = μb^2/(4π(1-ν)), and the approximation ln(R/r0) = 10 is used. After polygonization, the energy Eb of the grain boundary formed by these π dislocations per unit area is Eb = E0θ(0.5 - lnθ). The relative energy released per unit area of the grain boundary before and after polygonization compared to E1 is ΔE/E1 = (E1 - Eb)/E1 = (10θ E0 - E0θ(0.5 - lnθ))/(10θ E0) = (10 - 0.5 + ln10^-3)/10 = 25.99%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及能量释放的百分比计算，解答过程包含多个公式推导和数值代入。 | 知识层次: 题目涉及多步计算和概念关联，需要应用多个公式（如位错能量公式、晶界能量公式）并进行综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，题目涉及多个概念的理解和关联（如位错能量、亚晶界形成、能量释放计算等），并需要进行多步骤的计算（包括对数运算和百分比计算）。虽然题目提供了关键公式，但需要考生综合运用这些公式并正确代入数值（如θ=10^-3）才能得出最终答案。这种需要概念关联和综合计算的题目在选择题型中属于较复杂的类型。", "convertible": true, "correct_option": "25.99%", "choice_question": "The subgrain boundaries formed after polygonization contain π edge dislocations, and the misorientation between subgrains is 10^-3 radians. Assuming there is no interaction between dislocations before polygonization, how much energy is released after polygonization (expressed as a percentage)? (The grain boundary energy E⊥-E0θ(A-1)=β, where A is set to 0.5)", "conversion_reason": "The calculation question has a specific numerical answer (25.99%), which can be directly used as the correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "25.99%", "B": "12.50%", "C": "50.00%", "D": "7.32%" }, "correct_answer": "A", "explanation": "The correct answer is A (25.99%) as it is derived from the given grain boundary energy equation with A=0.5. Option B (12.50%) exploits cognitive bias by using half the correct value. Option C (50.00%) is a professional intuition trap suggesting complete energy release. Option D (7.32%) is a multi-level verification trap combining incorrect parameters from different material systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4142, "question": "With increasing temperature antiferromagnetic materials eventually become which of the following?(a) Diamagnetics(b) Paramagnetics(c) Ferromagnetics(d) Antiferromagnetics(e) Ferrimagnetics", "answer": "With increasing temperature antiferromagnetic materials eventually become paramagnetic.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且答案形式为从给定选项中选择一个最合适的选项。 | 知识层次: 题目考查对反铁磁材料在温度升高时转变为顺磁性这一基本概念的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要理解反铁磁材料在温度升高时的行为变化，但只需掌握基础概念（反铁磁性与顺磁性的转变关系）即可作答，不需要进行复杂的概念区分或多步骤推理。属于概念理解和简单辨析的层次。", "convertible": true, "correct_option": "Paramagnetics", "choice_question": "With increasing temperature antiferromagnetic materials eventually become which of the following?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer, making it directly convertible to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diamagnetics", "B": "Paramagnetics", "C": "Ferromagnetics", "D": "Ferrimagnetics" }, "correct_answer": "B", "explanation": "The correct answer is B (Paramagnetics) because antiferromagnetic materials lose their magnetic ordering above the Néel temperature and become paramagnetic. The interference options are designed as follows: A (Diamagnetics) exploits the common misconception that all magnetic materials eventually become diamagnetic at high temperatures. C (Ferromagnetics) creates confusion by suggesting a transition to a stronger magnetic state. D (Ferrimagnetics) plays on the similarity between antiferromagnetic and ferrimagnetic ordering, making it seem plausible for advanced AI models that might overgeneralize magnetic phase transitions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4419, "question": "Give the approximate temperature at which it is desirable to heat a 0.85 wt% C iron-carbon alloy during a full anneal heat treatment.", "answer": "About 777°C (1430°F)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从多个选项中选择或进行复杂的计算。虽然答案是一个具体的数值，但题目本身没有提供选项或要求进行计算步骤，而是直接询问一个特定的知识点的具体数值，这更符合简答题的特征。 | 知识层次: 题目考查对铁碳合金相图中关键温度点的记忆，特别是全退火处理时的适宜温度，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆一个具体的温度数值（777°C），属于基础概念记忆层次。题目不涉及概念解释或复杂体系分析，仅需直接回忆教材或课程中给出的标准热处理温度，因此属于最低难度等级。", "convertible": true, "correct_option": "About 777°C (1430°F)", "choice_question": "What is the approximate temperature at which it is desirable to heat a 0.85 wt% C iron-carbon alloy during a full anneal heat treatment?", "conversion_reason": "The answer is a specific and standard value, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "About 777°C (1430°F)", "B": "About 727°C (1340°F)", "C": "About 912°C (1674°F)", "D": "About 600°C (1112°F)" }, "correct_answer": "A", "explanation": "The correct answer is A because 0.85 wt% C is the eutectoid composition, and full annealing requires heating to about 50°C above the lower critical temperature (A1 line at 727°C), which is approximately 777°C. Option B is the lower critical temperature itself, a common mistake when confusing annealing with normalizing. Option C is the upper critical temperature (A3 line) for hypoeutectoid steels, exploiting confusion between different carbon contents. Option D is a temperature where no phase transformation occurs, targeting those who misapply recrystallization concepts to annealing.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3901, "question": "Calculate % IC of the interatomic bonds for the intermetallic compound TiAl3.", "answer": "0%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算TiAl3金属间化合物的离子键百分比(% IC)，需要使用相关公式进行计算，最终给出数值结果0%。这符合计算题的特征，需要数值计算和公式应用。 | 知识层次: 题目要求计算TiAl3的离子键百分比，这需要应用基本的化学键理论公式进行计算。虽然涉及对离子键和金属键的理解，但计算过程直接且不涉及多步推理或综合分析，属于基本公式的直接应用。 | 难度: 在选择题型中，该题目属于最低难度等级。题目仅要求直接套用基本公式（离子键百分比计算公式）进行简单计算，且正确选项为0%可以直接得出无需复杂计算步骤。属于单一公式直接应用的典型简单题目，在选择题型内相对难度极低。", "convertible": true, "correct_option": "0%", "choice_question": "What is the percentage of ionic character (% IC) of the interatomic bonds for the intermetallic compound TiAl3?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0%", "B": "15%", "C": "32%", "D": "47%" }, "correct_answer": "A", "explanation": "The correct answer is 0% because TiAl3 is an intermetallic compound where bonding is primarily metallic with minimal ionic character. Option B (15%) exploits the cognitive bias that Al-Ti systems might show some ionic character due to electronegativity difference. Option C (32%) is designed to trap those who incorrectly apply Pauling's formula for %IC without considering the metallic nature. Option D (47%) is an extreme value that might catch models relying on oversimplified electronegativity calculations without material-specific knowledge.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4723, "question": "Gold (Au) forms a substitutional solid solution with silver (Ag). Compute the weight percent of gold that must be added to silver to yield an alloy that contains 5.5 × 10^{21} \\mathrm{Au} atoms per cubic centimeter. The densities of pure \\mathrm{Au} and \\mathrm{Ag} are 19.32 and 10.49g / {cm}^{3}, respectively.", "answer": "15.9 wt%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解合金中金的重量百分比，答案是一个具体的数值（15.9 wt%），解答过程需要涉及密度、原子数等物理量的计算。 | 知识层次: 题目需要进行多步计算，包括原子浓度转换、密度计算和重量百分比计算，需要综合运用材料科学中的固溶体概念和数学计算能力。虽然不涉及复杂的机理分析或创新设计，但需要较强的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解固溶体、原子浓度、密度和重量百分比等多个概念，并进行多步计算和单位转换。虽然题目提供了正确选项，但解题过程涉及计算合金中金和银的原子数、体积分数以及最终的重量百分比，步骤较为复杂，需要较强的综合分析能力。", "convertible": true, "correct_option": "15.9 wt%", "choice_question": "Gold (Au) forms a substitutional solid solution with silver (Ag). What weight percent of gold must be added to silver to yield an alloy that contains 5.5 × 10^{21} Au atoms per cubic centimeter, given the densities of pure Au and Ag are 19.32 and 10.49 g/cm³, respectively?", "conversion_reason": "The calculation problem has a definite numerical answer, making it suitable for conversion into a multiple-choice question format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "15.9 wt%", "B": "23.4 wt%", "C": "10.2 wt%", "D": "18.7 wt%" }, "correct_answer": "A", "explanation": "The correct answer is A (15.9 wt%) because it accounts for the atomic densities and mass fractions correctly. Option B (23.4 wt%) is a cognitive bias trap, using a value that might seem plausible if one incorrectly assumes linear density mixing. Option C (10.2 wt%) exploits the common error of neglecting atomic mass differences between Au and Ag. Option D (18.7 wt%) is designed to catch those who might confuse weight percent with atomic percent calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1305, "question": "What type of structure is cementite?", "answer": "Cementite: an interstitial compound formed by iron and carbon, belonging to the orthorhombic system.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释cementite的结构类型，答案提供了详细的文字描述和分类信息，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对渗碳体（cementite）这一基本概念的定义和晶体结构的记忆，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别水泥体的基本定义和分类（铁和碳形成的间隙化合物，属于正交晶系）。这属于最基础的概念记忆层次，无需复杂推理或概念间的关联分析，因此属于等级1的基本定义简答难度。", "convertible": true, "correct_option": "an interstitial compound formed by iron and carbon, belonging to the orthorhombic system", "choice_question": "What type of structure is cementite?", "conversion_reason": "The answer is a standard definition of cementite, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An interstitial compound with orthorhombic structure", "B": "A substitutional solid solution with FCC structure", "C": "An intermetallic compound with BCC structure", "D": "An interstitial solid solution with HCP structure" }, "correct_answer": "A", "explanation": "Cementite is an interstitial compound of iron and carbon (Fe3C) with an orthorhombic crystal structure (A is correct). B is incorrect because cementite is not a substitutional solid solution nor FCC. C is a trap as BCC is common for iron but cementite is orthorhombic. D is wrong because while it involves interstitial mechanism, cementite is a compound not a solid solution and has orthorhombic not HCP structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1647, "question": "The equilibrium concentration of vacancies in metals follows the relationship $N_{\\\\mathrm{v}}=N\\\\mathrm{exp}\\\\left({-Q_{\\\\mathrm{v}}}/{}$ $R T)$ ). When a certain metal is heated to 1130K, the equilibrium concentration of vacancies is 5 times that at 1000K. Assuming the density of the metal remains unchanged between $1000\\\\sim1130\\\\mathrm{K}$ and the gas constant is 8.31J/( $\\\\mathbf{\\\\dot{mol}}\\\\cdot\\\\mathbf{K})$, calculate the vacancy formation energy $Q_{\\\\mathbf{v}}$.", "answer": "The equilibrium concentrations of vacancies at 1130K and 1000K are $N_{\\\\mathbf{v}1}$ and $N_{\\\\nabla2}$ respectively, then $$ \\\\frac{N_{\\\\mathrm{V1}}}{N_{\\\\mathrm{V2}}}={\\\\mathsf{S}}=\\\\frac{N\\\\mathrm{exp}\\\\Big(-\\\\frac{Q_{\\\\mathrm{v}}}{R T_{1}}\\\\Big)}{N\\\\mathrm{exp}\\\\Big(-\\\\frac{Q_{\\\\mathrm{v}}}{R T_{2}}\\\\Big)}\\\\bar{\\\\mathsf{S}}\\\\bar{\\\\mathsf{S}}=\\\\mathrm{exp}\\\\Big[-\\\\frac{Q_{\\\\mathrm{v}}}{R}\\\\Big(\\\\frac{1}{T_{1}}-\\\\frac{1}{T_{2}}\\\\Big)\\\\Big] $$ From this, $Q_{\\\\mathbf{v}}$ can be solved as $$ Q_{\\\\mathrm{v}}=-{\\\\frac{R{\\\\mathrm{ln}}{\\\\mathsf{S}}}{{\\\\frac{1}{T_{1}}}-{\\\\frac{1}{T_{2}}}}}=-{\\\\frac{[{\\\\mathrm{}}8.31]/{\\\\mathrm{~mol~}}\\\\cdot{\\\\mathrm{~K~}}]\\\\ln{\\\\mathsf{S}}}{{\\\\frac{1}{1130}}-{\\\\frac{1}{1000}}}}=116300{\\\\mathrm{J/mol}} $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解空缺形成能Qv，答案中包含了具体的计算步骤和最终数值结果，符合计算题的特征。 | 知识层次: 题目需要应用平衡浓度公式进行多步计算，涉及对数运算和温度倒数差的计算，需要理解公式中各参数的含义并进行适当的代数变换。虽然不涉及复杂的综合分析或机理解释，但比简单的直接套用公式更具挑战性。 | 难度: 在选择题中属于中等偏上难度，需要理解并应用平衡空位浓度的公式，进行多步数学推导和计算。题目涉及温度变化对空位浓度的影响，需要正确代入数值并解对数方程，最终得出空位形成能。虽然题目提供了公式和部分数值，但解题过程需要较强的综合分析能力和数学运算技巧。", "convertible": true, "correct_option": "116300 J/mol", "choice_question": "The equilibrium concentration of vacancies in metals follows the relationship $N_{\\mathrm{v}}=N\\mathrm{exp}\\left({-Q_{\\mathrm{v}}}/{}$ $R T)$ ). When a certain metal is heated to 1130K, the equilibrium concentration of vacancies is 5 times that at 1000K. Assuming the density of the metal remains unchanged between $1000\\sim1130\\mathrm{K}$ and the gas constant is 8.31J/( $\\mathbf{\\dot{mol}}\\cdot\\mathbf{K})$, the vacancy formation energy $Q_{\\mathbf{v}}$ is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a choice among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "116300 J/mol", "B": "92800 J/mol", "C": "145600 J/mol", "D": "77600 J/mol" }, "correct_answer": "A", "explanation": "正确答案A是通过正确应用Arrhenius关系式推导得出：ln(5) = Qv/R(1/1000 - 1/1130)。干扰项B是通过错误地忽略对数关系直接线性计算得出。干扰项C是反向应用温度比值(1130/1000)的常见直觉错误。干扰项D则是混淆了空位形成能与扩散激活能的典型错误，后者通常数值较小。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2609, "question": "In the periodic table, what are the differences in atomic structure from top to bottom for elements in the same main group?", "answer": "From top to bottom, the number of electron shells increases, and the atomic radius becomes larger.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释同一主族元素从上到下原子结构的变化，答案需要文字描述和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对元素周期表中同主族元素原子结构变化的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（元素周期表中同主族元素的原子结构变化），但需要考生理解并描述两个关键变化（电子层数增加和原子半径增大），而不仅仅是简单的定义回忆。这要求考生对周期表趋势有一定的理解和描述能力，但不需要复杂的分析或比较。", "convertible": true, "correct_option": "From top to bottom, the number of electron shells increases, and the atomic radius becomes larger.", "choice_question": "In the periodic table, what are the differences in atomic structure from top to bottom for elements in the same main group?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The number of electron shells increases, leading to greater atomic radius but constant effective nuclear charge", "B": "The number of valence electrons decreases while nuclear shielding increases proportionally", "C": "The principal quantum number increases but is offset by decreasing electronegativity", "D": "The core electron configuration remains identical while only valence orbitals expand" }, "correct_answer": "A", "explanation": "Correct answer A identifies the key changes: increasing electron shells and atomic radius, while noting effective nuclear charge remains relatively constant due to shielding. Option B incorrectly suggests valence electrons decrease (they stay constant in main groups). Option C's 'offset' phrasing creates a false balance between quantum number and electronegativity. Option D's 'identical core configuration' is misleading as core electrons do increase with period number.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3757, "question": "A 2-in. cube solidifies in 4.6 min. Calculate (b) the solidification time for a 0.5 in. x 0.5 in. x 6 in. bar cast under the same conditions. Assume that n=2.", "answer": "the solidification time for the bar is 0.60 min.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算凝固时间），并给出了具体的公式参数（n=2），最终答案是一个具体的数值结果（0.60 min），这些都是计算题的典型特征。 | 知识层次: 题目涉及基本公式的应用和简单计算，需要根据给定的条件和公式直接计算固结时间，不需要多步计算或综合分析。 | 难度: 在选择题中属于简单难度，题目要求应用基本公式（Chvorinov's rule）进行简单计算，仅需一步转换和代入，无需复杂分析或多公式组合。", "convertible": true, "correct_option": "0.60 min", "choice_question": "A 2-in. cube solidifies in 4.6 min. Under the same conditions, what is the solidification time for a 0.5 in. x 0.5 in. x 6 in. bar? Assume that n=2.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.60 min", "B": "1.15 min", "C": "2.30 min", "D": "4.60 min" }, "correct_answer": "A", "explanation": "正确答案A基于Chvorinov法则计算，t=C(V/A)^n。对于0.5x0.5x6in棒材，体积与表面积比(V/A)=0.125，而2in立方体为0.333。干扰项B错误地将时间与厚度成正比(0.5/2)*4.6=1.15。干扰项C错误地认为时间与横截面积相关(0.25/4)*4.6=2.30。干扰项D直接使用原始时间，忽略了尺寸效应。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2722, "question": "The vacancy formation energy (E_v) and interstitial atom formation energy (E_i) of Al are 0.76 eV and 3.0 eV, respectively. Calculate the ratio of the equilibrium concentration of vacancies to the equilibrium concentration of interstitial atoms in Al at room temperature (20℃).", "answer": "At 20℃: C_V/C_i = e^((1/(8.617×10^-5×293))(3.0-0.76)) = e^88.72 = 3.395×10^38", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及能量和温度的计算，最终需要得出一个具体的数值结果。答案的形式也是通过计算得出的数值，符合计算题的特征。 | 知识层次: 题目需要应用缺陷形成能的基本概念，进行多步计算（包括温度转换、玻尔兹曼因子计算和指数运算），并理解平衡浓度与形成能之间的关系。虽然不涉及复杂的综合分析或创新设计，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及空位形成能和间隙原子形成能的概念，以及平衡浓度比的计算。解题步骤包括温度转换、玻尔兹曼因子计算和指数运算，属于多步骤计算过程。虽然计算本身不复杂，但需要综合应用多个知识点，因此在选择题型内属于等级3的难度。", "convertible": true, "correct_option": "3.395×10^38", "choice_question": "The vacancy formation energy (E_v) and interstitial atom formation energy (E_i) of Al are 0.76 eV and 3.0 eV, respectively. What is the ratio of the equilibrium concentration of vacancies to the equilibrium concentration of interstitial atoms in Al at room temperature (20℃)?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.395×10^38", "B": "1.148×10^13", "C": "2.632×10^25", "D": "4.724×10^19" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Arrhenius equation for defect concentrations: exp[(E_i - E_v)/kT], where k is Boltzmann's constant and T is temperature in Kelvin. At 20℃ (293K), this gives exp[(3.0-0.76)/(8.617×10^-5×293)] = 3.395×10^38. Option B is a common error from using eV directly without temperature conversion. Option C results from incorrectly using the average formation energy. Option D comes from a unit conversion error between eV and J/mol.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 859, "question": "Tensile deformation is applied along the [123] direction of an aluminum (Al) single crystal to induce plastic deformation. Determine the rotation rule and rotation axis.", "answer": "During single slip, the specimen axis should rotate towards [101], and the rotation axis is [12¯3]×[10¯1]=[¯1¯1¯1].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述塑性变形过程中的旋转规则和旋转轴，答案提供了详细的文字解释和向量计算，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求确定单晶铝在拉伸变形过程中的旋转规则和旋转轴，这需要综合运用晶体塑性变形的基本原理、滑移系统的选择、晶体取向变化等知识。解答过程涉及多个概念的关联和综合分析，包括滑移方向的确定、旋转轴的计算以及旋转方向的判断，思维过程较为复杂，属于较高层次的认知要求。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "During single slip, the specimen axis should rotate towards [101], and the rotation axis is [12¯3]×[10¯1]=[¯1¯1¯1].", "choice_question": "Tensile deformation is applied along the [123] direction of an aluminum (Al) single crystal to induce plastic deformation. Which of the following correctly describes the rotation rule and rotation axis?", "conversion_reason": "The answer is a standard and specific description, which can be used as a correct option in a multiple-choice question. The question can be rephrased to ask for the correct description among possible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "During single slip, the specimen axis should rotate towards [101], and the rotation axis is [12¯3]×[10¯1]=[¯1¯1¯1]", "B": "During single slip, the specimen axis should rotate towards [111], and the rotation axis is [123]×[111]=[¯1¯1¯1]", "C": "During single slip, the specimen axis should rotate towards [101], and the rotation axis is [123]×[101]=[¯1¯1¯1]", "D": "During single slip, the specimen axis should rotate towards [111], and the rotation axis is [12¯3]×[10¯1]=[¯1¯1¯1]" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC crystals like aluminum, the slip direction is along <110> directions. The rotation axis is determined by the cross product of the initial tensile axis [123] and the slip direction [101], giving [12¯3]×[10¯1]=[¯1¯1¯1]. Option B incorrectly uses [111] as the rotation direction and wrong cross product vectors. Option C uses the correct rotation direction but wrong vectors for cross product. Option D combines correct rotation axis calculation with wrong rotation direction.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4182, "question": "Give the electron configuration for the ion Br-.", "answer": "The electron configuration for a Br- ion is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求给出Br-离子的电子排布，答案是一个详细的电子排布序列，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对电子排布这一基础概念的记忆和理解，不需要复杂的计算或分析，仅需直接应用原子序数和电子排布规则即可得出答案。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求的是基础概念记忆（电子排布），但需要考生掌握Br原子的电子排布（1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p5）并理解Br-离子是通过获得一个电子形成的（4p轨道填满）。这比单纯记忆元素符号或简单定义（等级1）要复杂，但比需要分析多个概念或进行复杂推导（等级3）要简单。", "convertible": true, "correct_option": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6", "choice_question": "What is the electron configuration for the Br- ion?", "conversion_reason": "The answer is a standard and specific electron configuration, which can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6", "B": "1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p5", "C": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p5", "D": "1s2 2s2 2p6 3s2 3p6 3d10 4s1 4p6" }, "correct_answer": "A", "explanation": "The correct answer is A because Br- gains one electron to achieve a stable noble gas configuration, filling the 4p orbital completely. Option B is the ground state configuration of neutral Br atom, exploiting the common mistake of not accounting for the extra electron. Option C mimics the correct configuration but misses the additional electron in 4p orbital, creating a subtle trap. Option D introduces an incorrect 4s1 configuration that might seem plausible due to transition metal electron configurations, but is invalid for Br-.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4400, "question": "Cite disadvantages of cold working.", "answer": "The disadvantages of cold working are: (1) High deformation energy requirements. (2) Large deformations must be accomplished in steps, which may be expensive. (3) A loss of ductility.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举冷加工的缺点，答案以文字解释和论述的形式呈现，没有提供选项或需要计算，符合简答题的特征。 | 知识层次: 题目考查对冷加工缺点的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列举冷加工的缺点，但选项已经提供了明确的答案，不需要考生自行回忆或组织语言。考生只需识别和选择正确的选项即可。然而，题目涉及的知识点需要考生对冷加工的基本概念和特性有一定的理解和记忆，属于概念解释和描述的层次，因此难度等级为2。", "convertible": true, "correct_option": "High deformation energy requirements, large deformations must be accomplished in steps, and a loss of ductility.", "choice_question": "Which of the following are disadvantages of cold working?", "conversion_reason": "The answer is a standard list of disadvantages, which can be formatted into a multiple-choice question with the correct option being the provided list.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High deformation energy requirements", "B": "Improved surface finish and dimensional accuracy", "C": "Reduced dislocation density due to dynamic recovery", "D": "Enhanced electrical conductivity through grain refinement" }, "correct_answer": "A", "explanation": "The correct answer is A because cold working requires significant energy to overcome the material's yield strength at room temperature. Option B is a cognitive bias trap - while true for cold working, it's actually an advantage not a disadvantage. Option C exploits professional intuition by suggesting a dislocation mechanism that only occurs in hot working. Option D uses a real material property change but misrepresents it as a disadvantage when it's typically beneficial.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2281, "question": "Predict the strength σLu of an Al2O3 short fiber reinforced composite at a volume fraction φf=0.1, given the fiber stress σf=2190MPa and the matrix yield strength σy=76MPa.", "answer": "For Al2O3 short fiber composites, the strength σLu = σf × φf + σy × (1 - φf) = 2190 × 0.1 + 76 × 0.9 = 386MPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和数值进行具体的计算，最终得出一个数值结果。答案展示了完整的计算过程和最终结果，符合计算题的特征。 | 知识层次: 题目主要考查基本公式的直接应用和简单计算，涉及复合材料强度的基本公式套用，无需多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需直接套用单一公式进行计算（σLu = σf × φf + σy × (1 - φf)），无需理解多个概念或进行复杂步骤。题目提供所有必要参数，仅需简单代入和基础算术运算即可得出答案，属于最基础的计算题类型。", "convertible": true, "correct_option": "386MPa", "choice_question": "Predict the strength σLu of an Al2O3 short fiber reinforced composite at a volume fraction φf=0.1, given the fiber stress σf=2190MPa and the matrix yield strength σy=76MPa.", "conversion_reason": "The calculation problem has a definite numerical answer, making it suitable for conversion into a multiple-choice question format where the correct option is the calculated result.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "386MPa", "B": "219MPa", "C": "76MPa", "D": "292MPa" }, "correct_answer": "A", "explanation": "The correct answer is A (386MPa) calculated using the rule of mixtures for short fiber composites: σLu = φfσf + (1-φf)σy. Option B (219MPa) is a common error from incorrectly using the inverse rule of mixtures. Option C (76MPa) traps those who consider only matrix contribution. Option D (292MPa) is a partial calculation error from neglecting matrix hardening effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2176, "question": "How is texture formed?", "answer": "After cold working, the orientations of metal grains exhibit certain relationships. For instance, certain crystal planes or directions become parallel to each other and also parallel to an external reference direction of the component. Such an orientation distribution is called preferred orientation or simply texture. The formation of texture is not limited to cold working, but here it mainly refers to deformation texture. In terms of both orientation and properties, polycrystalline materials with texture lie between single crystals and completely randomly oriented polycrystals.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对\"How is texture formed?\"进行解释和论述，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目不仅要求解释纹理的定义，还需要论述其形成机制和影响因素，涉及多步骤的推理分析和机理解释，思维深度较高。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解金属晶粒取向的基本概念，还需要掌握冷加工后晶粒取向变化的复杂机理，并能解释变形织构的形成过程。这涉及到对多晶体材料、单晶体和随机取向多晶体之间性质差异的综合分析，需要考生具备深厚的材料科学基础和机理推理能力。在选择题中，这种要求全面分析复杂现象并解释深层机理的题目属于最高难度。", "convertible": true, "correct_option": "After cold working, the orientations of metal grains exhibit certain relationships. For instance, certain crystal planes or directions become parallel to each other and also parallel to an external reference direction of the component. Such an orientation distribution is called preferred orientation or simply texture. The formation of texture is not limited to cold working, but here it mainly refers to deformation texture. In terms of both orientation and properties, polycrystalline materials with texture lie between single crystals and completely randomly oriented polycrystals.", "choice_question": "Which of the following best describes how texture is formed in metals?", "conversion_reason": "The answer is a standard explanation of a concept (texture formation in metals), which can be adapted into a multiple-choice format by presenting it as the correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Texture forms when dislocations rearrange into low-energy configurations during recovery annealing, creating preferred orientations", "B": "Texture arises from selective grain growth during recrystallization where grains with certain orientations consume others", "C": "Texture develops when external stresses cause systematic rotation of crystal lattices toward stable slip directions", "D": "Texture results from constitutional supercooling during solidification, creating aligned dendritic structures" }, "correct_answer": "C", "explanation": "The correct answer is C because deformation texture specifically forms when external stresses cause crystallographic planes to rotate toward stable slip systems. Option A describes recovery mechanisms that reduce texture. Option B describes recrystallization texture rather than deformation texture. Option D incorrectly associates texture with solidification patterns rather than plastic deformation. These distractors exploit common confusions between different texture formation mechanisms and processing stages.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3917, "question": "Which crystal system(s) listed below has (have) the following interaxial angle relationship?\n\\[\n\\alpha \\neq \\beta \\neq \\gamma \\neq 90^{\\circ}\n\\](a) Cubic(b) Hexagonal(c) Tetragonal(d) Rhombohedral(e) Orthorhombic(f) Monoclinic(g) Triclinic", "answer": "Triclinic is the only crystal system for which none of the interaxial angles are equal to one another and also not equal to 90^{\\circ}.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择符合特定晶体系统特征的正确答案 | 知识层次: 题目考查对晶体系统基本概念的记忆和理解，特别是对各晶系轴角关系的识别。 | 难度: 在选择题型中，该题目需要考生理解不同晶系的基本定义和特征，特别是对晶轴角度关系的记忆和简单辨析。虽然题目涉及多个晶系的比较，但正确选项（Triclinic）的特征较为明确，属于基础概念记忆和简单辨析的范畴，不需要复杂的分析或深度理解。因此，难度等级为2。", "convertible": true, "correct_option": "g", "choice_question": "Which crystal system listed below has the following interaxial angle relationship?\n\\[\n\\alpha \\neq \\beta \\neq \\gamma \\neq 90^{\\circ}\n\\]", "conversion_reason": "The original question is already in a multiple-choice format, and the answer specifies a single correct option (Triclinic, which corresponds to option g). Therefore, it can be treated as a single-choice question by identifying the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress (CRSS) is independent of crystal orientation in FCC metals", "B": "CRSS decreases with increasing temperature due to enhanced dislocation mobility", "C": "CRSS is higher for edge dislocations than screw dislocations in BCC metals at room temperature", "D": "CRSS follows Schmid's law only for single crystals, not polycrystals" }, "correct_answer": "C", "explanation": "Correct answer is C because in BCC metals at room temperature, the Peierls barrier causes higher CRSS for edge dislocations due to their wider core structure. Option A is incorrect (but tempting) because CRSS does depend on orientation via Schmid factor. Option B exploits thermal activation knowledge but oversimplifies temperature effects. Option D misapplies Schmid's law which governs single crystal behavior but exists in modified form for polycrystals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 976, "question": "How does melting point affect atomic diffusion within the same alloy system?", "answer": "Within the same alloy system, at the same temperature, diffusion is slower in alloys with higher melting points and faster in those with lower melting points.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释熔化点如何影响原子扩散，答案提供了文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求理解熔点与原子扩散之间的关系，并能在同一合金系统中进行比较分析。这需要将熔点与扩散速率的概念关联起来，进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及熔点和原子扩散之间的关系，要求考生在同一合金系统中对不同熔点的合金进行比较，并理解温度相同时扩散速率的变化。虽然不需要复杂的计算，但需要对材料科学中的基本概念有较好的掌握，并能进行综合分析。", "convertible": true, "correct_option": "Within the same alloy system, at the same temperature, diffusion is slower in alloys with higher melting points and faster in those with lower melting points.", "choice_question": "How does melting point affect atomic diffusion within the same alloy system?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "At the same homologous temperature (T/Tm), diffusion rates are identical regardless of melting point", "B": "Higher melting point alloys always exhibit faster diffusion due to stronger atomic bonds", "C": "Diffusion is slower in higher melting point alloys at the same absolute temperature", "D": "Melting point has no systematic relationship with diffusion rates in alloys" }, "correct_answer": "C", "explanation": "The correct answer is C because diffusion is thermally activated and higher melting point alloys have stronger atomic bonds that require more energy for atomic movement. Option A is a cognitive bias trap using homologous temperature incorrectly - while useful for comparing different materials, it doesn't apply within the same alloy system. Option B reverses the actual relationship, exploiting the 'stronger bonds must mean more activity' fallacy. Option D is a common oversimplification trap that ignores the fundamental connection between bond strength and diffusion barriers.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 333, "question": "Give the basic conditions (driving force) for metal recrystallization.", "answer": "There must be a certain amount of deformation stored energy and a certain temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出金属再结晶的基本条件（驱动力），答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查金属再结晶的基本条件，属于基本原理的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆金属再结晶的基本条件（变形储存能量和一定温度），属于基础概念记忆层次，无需复杂分析或推理，因此属于最低难度等级。", "convertible": true, "correct_option": "There must be a certain amount of deformation stored energy and a certain temperature.", "choice_question": "What are the basic conditions (driving force) for metal recrystallization?", "conversion_reason": "The answer is a standard concept that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Exceeding the material's melting temperature to enable atomic rearrangement", "B": "A critical combination of dislocation density and thermal activation energy", "C": "Application of external stress exceeding the yield strength", "D": "Maintaining constant strain rate during deformation" }, "correct_answer": "B", "explanation": "The correct answer is B because recrystallization requires both sufficient stored energy from dislocations (deformation) and thermal activation to allow atomic rearrangement. Option A is incorrect because recrystallization occurs well below melting temperature. Option C is a common confusion with plastic deformation conditions. Option D describes a deformation condition rather than recrystallization requirement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3239, "question": "Among the following alloy phase structures, the one with high melting point, high hardness, great brittleness, and simple crystal structure is A. Topologically close-packed phase B. Interstitial compound with complex lattice structure C. Electron compound D. Interstitial phase", "answer": "D", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对合金相结构基本特性的记忆和理解，如熔点、硬度、脆性和晶体结构的简单性等基础概念，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个合金相结构的特性比较，但正确选项D（间隙相）具有明确的特征描述（高熔点、高硬度、大脆性、简单晶体结构），这些特征在基础材料科学课程中通常会被强调和记忆。考生需要理解并辨析不同合金相结构的基本特性，但不需要进行复杂的分析或推导。因此，该题目在选择题型中属于概念理解和简单辨析的难度等级。", "convertible": true, "correct_option": "D. Interstitial phase", "choice_question": "Among the following alloy phase structures, the one with high melting point, high hardness, great brittleness, and simple crystal structure is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Topologically close-packed phase", "B": "Interstitial compound with complex lattice structure", "C": "Electron compound", "D": "Interstitial phase" }, "correct_answer": "D", "explanation": "Interstitial phases are characterized by their simple crystal structure, high melting point due to strong covalent bonds, high hardness from the rigid lattice, and inherent brittleness. The distractors exploit common misconceptions: A) TCP phases have complex structures, B) complex lattices contradict the simple structure requirement, C) electron compounds' properties vary widely and don't consistently meet all criteria. The key is recognizing that interstitial phases uniquely combine all specified properties despite their simple structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2539, "question": "Briefly describe the influence of crystal structure on solubility according to the Hume-Rothery rules", "answer": "Only when the two components have the same crystal structure can they form an infinite (or continuous) solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述晶体结构对溶解度的影响，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对Hume-Rothery规则中晶体结构对溶解度影响的基本概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是Hume-Rothery规则的基础概念记忆，但需要考生理解并描述晶体结构对溶解度的具体影响，而不仅仅是简单的定义复述。题目要求考生能够将基本原理与具体现象联系起来，属于\"概念解释和描述\"层次的知识运用。", "convertible": true, "correct_option": "Only when the two components have the same crystal structure can they form an infinite (or continuous) solid solution.", "choice_question": "According to the Hume-Rothery rules, which of the following statements correctly describes the influence of crystal structure on solubility?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Only when the two components have the same crystal structure can they form an infinite (or continuous) solid solution", "B": "The difference in crystal structure can be compensated by adjusting the atomic size factor to achieve complete solubility", "C": "Crystal structure similarity is necessary but not sufficient for forming extensive solid solutions", "D": "Different crystal structures can form infinite solid solutions if their electronegativity difference is less than 0.4" }, "correct_answer": "A", "explanation": "The correct answer A directly states the Hume-Rothery rule that identical crystal structure is required for infinite solubility. B is a cognitive bias trap, mixing the atomic size factor (a separate rule) with crystal structure requirement. C is a professional intuition trap, sounding plausible but incorrectly suggesting crystal structure alone isn't sufficient. D is a multi-level verification trap, combining electronegativity (a real factor) with the wrong solubility condition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3033, "question": "The Tg of the glass phase in ceramics is (5).", "answer": "(5)Glass transition temperature", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（玻璃转变温度），需要学生对相关概念有准确理解并用文字作答，属于简答题类型 | 知识层次: 题目考查对玻璃相变温度（Tg）这一基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求识别和记忆\"Tg\"的基本定义（Glass transition temperature），属于最基础的概念记忆层次。无需解释、分析或比较多个概念，解题步骤极为简单，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "Glass transition temperature", "choice_question": "The Tg of the glass phase in ceramics is:", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Glass transition temperature", "B": "Thermal decomposition temperature", "C": "Crystallization onset temperature", "D": "Elastic modulus transition point" }, "correct_answer": "A", "explanation": "The correct answer is A because Tg specifically refers to the glass transition temperature where the amorphous phase transitions from a hard/glassy state to a soft/rubbery state. Option B is incorrect as it describes a chemical decomposition process, not a phase transition. Option C is a plausible distractor as crystallization is related to glass phases, but occurs at a different temperature range. Option D exploits confusion between thermal transitions and mechanical properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1223, "question": "Generally, the higher the activation energy for atomic diffusion in a crystal, the larger the diffusion coefficient and the faster the diffusion rate.", "answer": "~\\\\times~", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（\"Generally, the higher the activation energy for atomic diffusion in a crystal, the larger the diffusion coefficient and the faster the diffusion rate.\"），并要求判断其正确性（答案标记为~\\\\times~表示错误）。这是典型的判断题形式，不需要计算或解释，只需判断陈述的对错。 | 知识层次: 题目考查对原子扩散基本概念的理解，即激活能与扩散系数之间的关系，属于基础概念的记忆和理解层面。 | 难度: 该题目属于基础概念正误判断，仅需记忆激活能与扩散系数之间的关系即可作答，无需复杂推理或概念比较。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "~\\\\times~", "choice_question": "Generally, the higher the activation energy for atomic diffusion in a crystal, the larger the diffusion coefficient and the faster the diffusion rate.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all crystalline materials, the diffusion coefficient follows an Arrhenius relationship with temperature, meaning it always decreases exponentially with decreasing temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the Arrhenius relationship (D = D₀exp(-Q/RT)) generally holds for most crystalline materials, there are exceptions where diffusion mechanisms change at certain temperatures (e.g., pipe diffusion along dislocations becoming dominant at lower temperatures). Additionally, some materials exhibit non-Arrhenius behavior due to complex diffusion mechanisms or phase transitions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1433, "question": "What is the most closely packed direction in a hexagonal close-packed crystal?", "answer": "<1120>", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个特定的晶体学方向，需要专业知识来识别和表述，答案是一个具体的晶体学方向指标（<1120>），而不是从多个选项中选择或简单的对错判断，也不需要复杂的计算过程。 | 知识层次: 题目考查对六方密堆积晶体中最密排方向的基本概念记忆，属于晶体学基础知识的直接回忆 | 难度: 在选择题型中，该题目仅要求记忆六方密堆积晶体中最密排方向的基本定义，属于基础概念记忆层次。题目仅需直接回忆特定知识点（<1120>方向），无需解释或复杂分析，因此属于最简单的难度等级。", "convertible": true, "correct_option": "<1120>", "choice_question": "Which of the following is the most closely packed direction in a hexagonal close-packed crystal?", "conversion_reason": "The answer is a standard crystallographic direction notation, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "<1120>", "B": "<0001>", "C": "<1010>", "D": "<1011>" }, "correct_answer": "A", "explanation": "The <1120> direction is the most closely packed in HCP because it lies along the edge of the basal plane where atoms are in direct contact. Option B <0001> is the c-axis direction which has a longer interatomic spacing. Option C <1010> is a common slip direction but not the most closely packed. Option D <1011> is a pyramidal direction with intermediate packing density. The trap is that AI models may confuse the most closely packed plane (0001) with the most closely packed direction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4841, "question": "An n-type semiconductor is known to have an electron concentration of 5 × 10^{17}{m}^{-3}. If the electron drift velocity is 350{m} / s in an electric field of 1000V / m, calculate the conductivity of this material.", "answer": "the conductivity of the material is 0.028, (\\omega·m)^{-1}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解材料的电导率，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过给定的电子浓度、电子漂移速度和电场强度来计算电导率。虽然需要理解半导体物理中的基本概念，但整体思维过程较为直接，属于基本公式的直接套用和简单计算。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要理解半导体电导率的基本概念，但解题步骤相对直接，仅需套用电导率公式（σ = n·e·μ，其中μ可通过漂移速度与电场关系求得）。题目提供了所有必要参数，且计算过程不涉及复杂转换或多步骤推导，属于选择题型中中等偏下的难度水平。", "convertible": true, "correct_option": "0.028 (Ω·m)^{-1}", "choice_question": "An n-type semiconductor is known to have an electron concentration of 5 × 10^{17} m^{-3}. If the electron drift velocity is 350 m/s in an electric field of 1000 V/m, what is the conductivity of this material?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.028 (Ω·m)^{-1}", "B": "0.175 (Ω·m)^{-1}", "C": "0.280 (Ω·m)^{-1}", "D": "0.035 (Ω·m)^{-1}" }, "correct_answer": "A", "explanation": "正确答案A是通过σ = n·e·μ计算得出，其中迁移率μ = v_d/E = 350/1000 = 0.35 m²/V·s。干扰项B错误地直接使用n·v_d = 5e17×350。干扰项C错误地使用了n·e = 5e17×1.6e-19。干扰项D错误地使用了n·E = 5e17×1000。这些干扰项利用了常见的单位混淆和参数误用策略。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2696, "question": "Calculate the packing density of the diamond structure.", "answer": "Diamond is the most typical covalent crystal, entirely bonded by covalent bonds. Its crystal structure belongs to a complex fcc structure, where each C atom (d=0.1544 nm) has 4 equidistant nearest neighbors, conforming to the 8-N rule. The distance between the nearest neighbors is equivalent to the bond length. Based on the crystal structure of diamond, it can be determined that: Therefore, $$ a={\\frac{4\\times0.1544}{\\sqrt{3}}}=0.3566({\\mathrm{nm}})$$ $$ {\\cal K}=\\frac{8\\times\\frac43\\pi r^{3}}{a^{3}}=\\frac{8\\times\\frac43\\pi\\left(\\frac{0.1544}{2}\\right)^{3}}{(0.3566)^{3}}=0.34$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案中包含了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目需要理解金刚石结构的晶体学特征，应用几何关系进行多步计算，包括晶格常数推导和堆积密度公式应用，涉及概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解金刚石晶体结构的基本概念（如fcc结构、8-N规则、共价键特性），并能够进行多步骤计算（包括键长与晶格常数的转换、堆积密度公式的应用）。虽然题目提供了部分计算过程，但考生仍需掌握相关晶体学知识和数学推导能力才能正确理解和验证计算结果。", "convertible": true, "correct_option": "0.34", "choice_question": "What is the packing density of the diamond structure?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.34", "B": "0.52", "C": "0.68", "D": "0.74" }, "correct_answer": "A", "explanation": "The diamond structure's packing density is 0.34 due to its open tetrahedral coordination. Option B (0.52) mimics the face-centered cubic packing density, exploiting confusion between close-packed and open structures. Option C (0.68) represents the body-centered cubic packing density, a common misapplication from metallic systems. Option D (0.74) is the maximum theoretical packing density for spheres, creating a cognitive trap by suggesting diamond could achieve close-packing.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1506, "question": "Compared with pure iron, how do the plasticity and toughness of ferrite change", "answer": "Lower", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和比较纯铁和铁素体的塑性和韧性变化，需要文字论述而非简单选择或判断 | 知识层次: 题目考查的是对纯铁和铁素体塑性及韧性差异的基础概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即纯铁与铁素体的塑性和韧性比较。题目仅要求选择正确选项\"Lower\"，无需解释或分析，属于最基本的知识点掌握深度要求。解题步骤极其简单，只需回忆相关定义即可作答，因此属于等级1难度。", "convertible": true, "correct_option": "Lower", "choice_question": "Compared with pure iron, how do the plasticity and toughness of ferrite change?", "conversion_reason": "The answer is a standard term that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Higher due to reduced dislocation density", "B": "Lower because of increased grain boundary resistance", "C": "Remains unchanged as both are BCC structures", "D": "Depends on the carbon content in ferrite" }, "correct_answer": "B", "explanation": "The correct answer is B because ferrite, while being a nearly pure iron phase, has slightly lower plasticity and toughness compared to pure iron due to increased grain boundary resistance from minor alloying elements. Option A exploits the common misconception that reduced dislocation density always improves mechanical properties. Option C creates confusion by suggesting identical behavior in BCC structures while ignoring microstructural differences. Option D introduces a plausible but irrelevant variable (carbon content) since ferrite by definition has negligible carbon solubility.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3737, "question": "The activation energy for self-diffusion in copper is 49,300 cal / mol. A copper specimen creps as t 0.002 N / fn .-h when a stress of 15,000 psi is applied at 600^{\\circ} C. If the creep rate of copper is dependent on self-diffusion, determine the creep rate if the temperature is 800^{\\circ} C.", "answer": "the creep rate is 0.4, N / in·h.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（涉及激活能、温度变化对蠕变速率的影响）来求解特定温度下的蠕变速率，最终答案是一个具体的数值结果。 | 知识层次: 题目涉及多步计算和概念关联，需要应用阿伦尼乌斯公式和蠕变速率与温度的关系进行综合分析，思维过程有一定深度要求。 | 难度: 在选择题中属于中等偏上难度，需要理解激活能、蠕变速率与温度的关系，并应用阿伦尼乌斯公式进行多步计算。题目涉及多个概念的综合应用和复杂计算过程，但选择题型提供了正确选项，降低了部分难度。", "convertible": true, "correct_option": "the creep rate is 0.4, N / in·h.", "choice_question": "The activation energy for self-diffusion in copper is 49,300 cal / mol. A copper specimen creeps at 0.002 N / in·h when a stress of 15,000 psi is applied at 600°C. If the creep rate of copper is dependent on self-diffusion, determine the creep rate if the temperature is 800°C.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.4 N/in·h", "B": "0.04 N/in·h", "C": "0.002 N/in·h", "D": "0.004 N/in·h" }, "correct_answer": "A", "explanation": "The correct answer is A (0.4 N/in·h) because the creep rate follows an Arrhenius-type temperature dependence with the given activation energy. The key calculation involves converting temperatures to Kelvin (873K vs 1073K) and applying the exponential relationship. Option B (0.04) is designed to trap those who miscalculate the temperature conversion or exponent. Option C (0.002) exploits the cognitive bias of assuming no change with temperature. Option D (0.004) is a linear extrapolation trap that ignores the exponential nature of thermally activated processes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2120, "question": "Point out the error in the following concept and correct it: Under non-equilibrium crystallization conditions, alloys located inside near the endpoints of the eutectic line are more prone to forming divorced eutectic structures than those outside.", "answer": "Alloys located outside near the endpoints of the eutectic line are more prone than those inside.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择或判断 | 知识层次: 题目要求识别并纠正非平衡结晶条件下合金组织形成的错误概念，需要理解共晶线端点附近合金的凝固行为差异，并应用相变原理进行分析判断。这涉及多个概念的关联和综合分析，但不需要进行复杂的机理推导或创新设计。 | 难度: 在选择题中属于中等难度，需要理解非平衡结晶条件和共晶线端点附近合金的行为差异，并能准确识别和纠正概念错误。题目要求考生将理论知识与实际应用相结合，进行概念关联和综合分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Alloys located outside near the endpoints of the eutectic line are more prone than those inside.", "choice_question": "Under non-equilibrium crystallization conditions, which of the following statements is correct regarding the formation of divorced eutectic structures?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question because the answer is a specific and correct statement that can be presented as one of the options. The question can be rephrased to ask for the correct statement among possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The divorced eutectic formation is primarily controlled by the cooling rate rather than composition position", "B": "Alloys near the eutectic point show higher divorced eutectic tendency due to constitutional undercooling", "C": "Divorced eutectics form more easily in hypereutectic alloys due to primary phase nucleation barriers", "D": "The divorced eutectic morphology results from insufficient diffusion time for solute partitioning" }, "correct_answer": "A", "explanation": "The correct answer is A because under non-equilibrium conditions, cooling rate dominates over composition in determining divorced eutectic formation. Option B is a cognitive bias trap - while constitutional undercooling is real, it doesn't correlate with divorced eutectic formation. Option C exploits professional intuition about nucleation barriers but misapplies it to the wrong mechanism. Option D is a multi-level trap - while mentioning diffusion time is partially correct, it incorrectly attributes this to solute partitioning rather than phase separation kinetics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1220, "question": "Peritectic transformation refers to the transformation in which a liquid phase interacts with a solid phase, enveloping the original solid phase to form another new solid phase.", "answer": "~\\surd~", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（包晶转变的定义），并要求判断其正确性（答案标记为正确符号~\\surd~），这符合判断题的特征 | 知识层次: 题目考查对包晶转变（Peritectic transformation）这一基本概念的记忆和理解，属于定义性知识的判断，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目直接给出了包晶转变的定义，要求判断其正确性。这种题目只需要学生对基础概念有记忆即可作答，不需要深入理解或分析多个概念。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "~\\surd~", "choice_question": "Peritectic transformation refers to the transformation in which a liquid phase interacts with a solid phase, enveloping the original solid phase to form another new solid phase.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect brittleness under all loading conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While ceramics are generally brittle, certain advanced ceramics can exhibit limited plasticity under specific conditions (e.g., high temperatures or hydrostatic pressure). The use of 'all' and 'perfect' makes this statement incorrect as it ignores exceptions and special cases in material behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3060, "question": "What type of chemical bond is primarily found in carbides? A. Metallic bond B. Covalent bond C. Molecular bond D. Ionic bond", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对碳化物中主要化学键类型的基础概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要记忆碳化物的主要化学键类型，但选项中的概念区分较为明确（金属键、共价键、分子键、离子键），且共价键是碳化物最典型的键型这一知识点在基础化学中较为常见。不过仍需要一定的概念理解能力来排除其他干扰选项，因此属于等级2难度。", "convertible": true, "correct_option": "B. Covalent bond", "choice_question": "What type of chemical bond is primarily found in carbides?", "conversion_reason": "The original question is already in a multiple-choice format, which can be directly used as a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ionic bond with partial covalent character", "B": "Pure covalent bond", "C": "Metallic bond with electron delocalization", "D": "Hybrid bond with dominant ionic character" }, "correct_answer": "B", "explanation": "The correct answer is B because carbides primarily form covalent bonds due to the small size and high electronegativity of carbon. Option A exploits the common misconception that metal-carbon bonds must have ionic character. Option C traps those who overgeneralize metallic bonding in transition metal carbides. Option D targets the intuitive but incorrect assumption that metal-nonmetal compounds are always ionic.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 639, "question": "Divorced eutectic", "answer": "Divorced eutectic: In alloys with eutectic reactions, if the composition is far from the eutectic point, due to the large amount of primary crystals and the small amount of eutectic, the same phase in the eutectic as the primary crystals attaches to the primary crystals and grows, while the other phase in the eutectic appears separately distributed, causing the eutectic structure to lose its characteristic organizational features.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Divorced eutectic\"进行详细的文字解释和论述，而不是选择、判断或计算。答案提供了对该术语的详细描述，符合简答题的特征。 | 知识层次: 题目考查对\"Divorced eutectic\"这一专业术语的定义和基本特征的理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度。虽然涉及了共晶反应和离异共晶的概念，但题目已经给出了明确的定义和解释，不需要考生进行复杂的分析或比较。考生只需理解并记忆相关概念即可正确作答。相对于基本定义简答的等级1，该题目需要更深入一点的概念理解，但不需要达到复杂概念体系阐述的等级3。", "convertible": true, "correct_option": "Divorced eutectic: In alloys with eutectic reactions, if the composition is far from the eutectic point, due to the large amount of primary crystals and the small amount of eutectic, the same phase in the eutectic as the primary crystals attaches to the primary crystals and grows, while the other phase in the eutectic appears separately distributed, causing the eutectic structure to lose its characteristic organizational features.", "choice_question": "下列关于Divorced eutectic的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Divorced eutectic occurs when one phase in the eutectic attaches to primary crystals while the other phase appears separately, losing characteristic eutectic features", "B": "Divorced eutectic is a special case where eutectic phases completely separate into distinct layers due to high cooling rates", "C": "Divorced eutectic results from the complete suppression of one eutectic phase when composition deviates from eutectic point", "D": "Divorced eutectic describes the phenomenon where eutectic phases maintain their structure but grow independently of primary crystals" }, "correct_answer": "A", "explanation": "Option A correctly describes divorced eutectic where the same phase attaches to primary crystals while the other appears separately. Option B incorrectly suggests layer formation due to cooling rate. Option C wrongly implies phase suppression rather than attachment. Option D inaccurately maintains eutectic structure would remain intact.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 554, "question": "5.After recrystallization is completed, grain growth can be divided into (14) grain growth and (15) grain growth.", "answer": "(14) normal; (15) abnormal", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个特定的术语（normal和abnormal）来补充句子，属于需要简短文字回答的题目类型。虽然形式类似于填空题，但在给定的题型选项中最接近的是简答题（short_answer）。 | 知识层次: 题目考查的是对再结晶完成后晶粒生长类型的记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目仅要求考生记忆并区分两种晶粒生长的类型（正常晶粒生长和异常晶粒生长），不需要进行概念解释或复杂分析。知识点掌握深度要求较低，解题步骤简单，属于最基础的概念记忆题。", "convertible": true, "correct_option": "normal; abnormal", "choice_question": "After recrystallization is completed, grain growth can be divided into which two types?", "conversion_reason": "The answer is standard terminology and can be converted into a multiple-choice format by asking for the two types of grain growth.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "normal; abnormal", "B": "primary; secondary", "C": "continuous; discontinuous", "D": "isotropic; anisotropic" }, "correct_answer": "A", "explanation": "正确答案是A，因为再结晶完成后晶粒生长确实分为正常生长（normal）和异常生长（abnormal）。B选项利用初级/次级再结晶的概念混淆；C选项采用连续/不连续再结晶的术语干扰；D选项则用各向同性/各向异性这种材料性能描述来制造认知偏差。这些干扰项都利用了材料科学中容易混淆的术语对，且表面看起来都符合'两种类型'的题目要求。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4418, "question": "Give the approximate temperature at which it is desirable to heat a 0.45 wt% C iron-carbon alloy during a full anneal heat treatment.", "answer": "About 830°C (1525°F)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从选项中选择或进行判断。虽然答案是一个数值，但解答过程需要基于材料科学知识和对热处理工艺的理解，属于需要简要回答的问题类型。 | 知识层次: 题目考查对铁碳合金热处理温度的直接应用，需要记忆特定成分合金的退火温度，属于基本知识的直接应用，不涉及复杂计算或多概念关联。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需根据铁碳相图的基本知识直接套用0.45 wt% C对应的完全退火温度（A3线以上30-50°C），无需复杂计算或分析过程。题目考察的是对基础热处理参数的记忆和应用能力，属于选择题中较为基础的难度级别。", "convertible": true, "correct_option": "About 830°C (1525°F)", "choice_question": "What is the approximate temperature at which it is desirable to heat a 0.45 wt% C iron-carbon alloy during a full anneal heat treatment?", "conversion_reason": "The answer is a specific temperature value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "About 830°C (1525°F)", "B": "About 727°C (1340°F)", "C": "About 912°C (1674°F)", "D": "About 600°C (1112°F)" }, "correct_answer": "A", "explanation": "The correct answer is A because full annealing requires heating to about 50°C above the A3 line (around 780°C for 0.45% C) to achieve complete austenitization. Option B is the eutectoid temperature which is a common but incorrect first guess. Option C is the γ-Fe to δ-Fe transition temperature which is irrelevant here. Option D exploits the misconception that lower temperatures might suffice for annealing.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1799, "question": "Briefly describe the difference between grain growth and secondary recrystallization", "answer": "Grain growth is the continuous increase in average grain size, with uniform grain size growth, and pores remaining at grain boundaries or grain boundary intersections; secondary recrystallization is the abnormal growth of individual grains, with pores being trapped inside the grains. Secondary recrystallization is also related to the particle size of the raw material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述两种现象的区别，答案以文字解释和论述的形式呈现，没有选项、判断或计算要求。 | 知识层次: 题目考查对晶粒生长和二次再结晶这两个基本概念的记忆和理解，主要涉及定义和基本特征的描述，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个概念的定义和比较，但正确选项已经提供了清晰的对比描述，不需要复杂的推理或分析。主要考察的是对基础概念的理解和记忆，属于概念解释和描述的层次。", "convertible": true, "correct_option": "Grain growth is the continuous increase in average grain size, with uniform grain size growth, and pores remaining at grain boundaries or grain boundary intersections; secondary recrystallization is the abnormal growth of individual grains, with pores being trapped inside the grains. Secondary recrystallization is also related to the particle size of the raw material.", "choice_question": "Which of the following accurately describes the difference between grain growth and secondary recrystallization?", "conversion_reason": "The answer is a standard description of the difference between two concepts, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain growth involves uniform coarsening of all grains with pores remaining at boundaries, while secondary recrystallization features abnormal growth of select grains that engulf pores", "B": "Both processes result in uniform grain size increase, but secondary recrystallization occurs at higher temperatures than normal grain growth", "C": "Grain growth is driven by surface energy reduction, while secondary recrystallization is caused by strain energy differences between grains", "D": "Secondary recrystallization requires the presence of impurities to pin boundaries, whereas grain growth occurs in pure materials without impurities" }, "correct_answer": "A", "explanation": "The correct answer A precisely captures the key differences: uniform vs abnormal growth, and pore location behavior. Option B is wrong because it falsely claims both processes produce uniform grain size. Option C is partially correct but misleading as both processes can be driven by both surface and strain energy. Option D creates a false dichotomy as both processes can occur with or without impurities, and impurity effects are more complex than stated.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4348, "question": "What is the composition of the alloy if eutectoid cementite exists in addition to proeutectoid cementite?", "answer": "the alloy composition is 1.11 wt% c.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释合金的组成情况，并给出了具体的成分数值，需要文字解释和论述来回答，而不是简单的选择、判断或计算。 | 知识层次: 题目需要理解共析渗碳体和先共析渗碳体的概念，并进行多步计算来确定合金成分。这涉及到相图的应用和综合分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，需要考生掌握铁碳相图的基本概念，理解共析渗碳体和先共析渗碳体的形成条件，并能进行多步计算和综合分析。题目不仅要求考生识别合金成分，还需要将多个知识点关联起来，进行较为复杂的推理和计算。", "convertible": true, "correct_option": "the alloy composition is 1.11 wt% c", "choice_question": "What is the composition of the alloy if eutectoid cementite exists in addition to proeutectoid cementite?", "conversion_reason": "The answer is a specific and standard term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.11 wt% C", "B": "0.76 wt% C", "C": "0.83 wt% C", "D": "1.43 wt% C" }, "correct_answer": "A", "explanation": "The correct answer is A (1.11 wt% C) because this is the composition where both eutectoid and proeutectoid cementite can coexist in the microstructure. Option B (0.76 wt% C) is a common trap as it's the eutectoid composition where only eutectoid cementite forms. Option C (0.83 wt% C) exploits the cognitive bias toward intermediate values. Option D (1.43 wt% C) represents hypereutectoid alloys where only proeutectoid cementite exists, creating a professional intuition trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3882, "question": "Materials Science and Engineering is the study of material behavior & performance and how this is simultaneously related to structure, properties, and processing. Which of the following is the best example of a material property? (a) Density (b) Annealing (c) Forging (d) Single-crystal (e) Crystalline", "answer": "(a) Density", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择最佳答案，符合选择题的特征 | 知识层次: 题目考查对材料性能基本概念的记忆和理解，仅需识别出密度是材料性能的典型例子，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于基础概念识别，直接记忆的难度等级。题目要求识别材料属性的最佳例子，正确选项(a) Density是一个基本的材料属性，属于材料科学中最基础的概念之一。其他选项如(b) Annealing和(c) Forging是加工过程，(d) Single-crystal和(e) Crystalline是结构描述，与属性无关。因此，只需简单记忆和识别即可选出正确答案，无需深入理解或复杂分析。", "convertible": true, "correct_option": "Density", "choice_question": "Materials Science and Engineering is the study of material behavior & performance and how this is simultaneously related to structure, properties, and processing. Which of the following is the best example of a material property?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch coefficient for nanocrystalline copper", "B": "The stacking fault energy of austenitic stainless steel", "C": "The recrystallization temperature of cold-worked aluminum", "D": "The critical resolved shear stress for magnesium single crystals" }, "correct_answer": "B", "explanation": "The stacking fault energy is an intrinsic material property that characterizes the energy required to create a stacking fault in the crystal lattice. The Hall-Petch coefficient (A) is structure-sensitive and depends on grain boundary characteristics. The recrystallization temperature (C) is processing-dependent and varies with deformation conditions. The critical resolved shear stress (D) is orientation-dependent and thus not a fundamental material property. Advanced AI models may incorrectly select A due to its apparent material-specific nature, or D due to confusion with intrinsic lattice resistance to dislocation motion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4840, "question": "At room temperature the electrical conductivity of P b S is 25\\left(\\Omega·m\\right)^{-1}, whereas the electron and hole mobilities are 0.06 and 0.02{m}^{2} / V·s, respectively. Compute the intrinsic carrier concentration for PbS at room temperature.", "answer": "the intrinsic carrier concentration for pbs at room temperature is 1.95 × 10^{21}{m}^{-3}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的电导率、电子和空穴迁移率等参数，应用相关公式计算本征载流子浓度。答案是一个具体的数值结果，需要通过计算得出。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过给定的电导率、电子和空穴迁移率来计算本征载流子浓度。虽然需要理解相关概念，但计算过程直接且无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算本征载流子浓度，只需直接套用电导率与载流子浓度和迁移率的关系公式（σ = n_i * e * (μ_e + μ_h)），并进行简单的代数运算即可得出答案。无需多个公式组合或复杂的概念理解，因此属于最基础的难度等级。", "convertible": true, "correct_option": "1.95 × 10^{21} m^{-3}", "choice_question": "At room temperature the electrical conductivity of PbS is 25 (Ω·m)^{-1}, whereas the electron and hole mobilities are 0.06 and 0.02 m^{2}/V·s, respectively. What is the intrinsic carrier concentration for PbS at room temperature?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.95 × 10^{21} m^{-3}", "B": "3.13 × 10^{20} m^{-3}", "C": "5.21 × 10^{21} m^{-3}", "D": "7.81 × 10^{19} m^{-3}" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula σ = n_i * e * (μ_e + μ_h), where σ is conductivity, n_i is intrinsic carrier concentration, e is electron charge, μ_e and μ_h are electron and hole mobilities respectively. Option B is obtained by incorrectly using only electron mobility. Option C results from misplacing the decimal point in mobility values. Option D comes from confusing intrinsic with extrinsic carrier concentration.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 543, "question": "Pearlite", "answer": "Pearlite: The product of eutectoid transformation in iron-carbon alloys, it is a lamellar mixture of eutectoid ferrite and eutectoid cementite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Pearlite\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对珠光体（Pearlite）这一基本概念的记忆和理解，要求回答其定义和组成，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆（珠光体的定义），但正确选项提供了较为详细的描述（包括组成相和形成过程），这比单纯记忆基本定义（等级1）要求更高。学生需要理解并区分\"eutectoid ferrite\"和\"eutectoid cementite\"等术语，但不需要进行复杂的体系阐述或分析（等级3）。", "convertible": true, "correct_option": "The product of eutectoid transformation in iron-carbon alloys, it is a lamellar mixture of eutectoid ferrite and eutectoid cementite.", "choice_question": "Which of the following best describes pearlite?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The product of eutectoid transformation in iron-carbon alloys, it is a lamellar mixture of eutectoid ferrite and eutectoid cementite", "B": "A metastable phase formed during rapid quenching of steel, consisting of supersaturated carbon in a body-centered tetragonal iron matrix", "C": "The equilibrium phase in pure iron at room temperature, characterized by a body-centered cubic crystal structure", "D": "A high-temperature phase in steel that forms above the upper critical temperature, with a face-centered cubic crystal structure" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes pearlite as the eutectoid reaction product in iron-carbon systems. Option B describes martensite, exploiting confusion between transformation products. Option C describes ferrite, targeting basic crystal structure confusion. Option D describes austenite, exploiting high-temperature phase misconceptions. These traps leverage: 1) Common phase transformation confusions (B), 2) Fundamental crystal structure misunderstandings (C), and 3) Temperature-dependent phase misattributions (D). Advanced AI might select B due to the technical accuracy of its martensite description, or D by overemphasizing high-temperature behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1892, "question": "7. Martensitic transformation has the following characteristics: (19) etc.", "answer": "(19) Presence of habit plane", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求补充马氏体相变的特征，需要填写具体的文字描述（如\"Presence of habit plane\"），属于需要文字解释的简答题形式。 | 知识层次: 题目考查马氏体相变的基本特征，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆马氏体相变的基本特征之一（存在惯习面），属于基础概念记忆层次。题目仅涉及单一知识点的直接回忆，无需解释或分析，因此属于最低难度等级。", "convertible": true, "correct_option": "Presence of habit plane", "choice_question": "Which of the following is a characteristic of Martensitic transformation?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Presence of habit plane", "B": "Requires long-range diffusion of atoms", "C": "Exhibits time-dependent transformation kinetics", "D": "Always results in increased ductility" }, "correct_answer": "A", "explanation": "The correct answer is A because martensitic transformation is characterized by a specific crystallographic orientation relationship between parent and product phases, manifested as a habit plane. Option B is incorrect as martensitic transformation is diffusionless. Option C is a trap as it describes nucleation-and-growth transformations, while martensite forms instantaneously at atomic scale. Option D exploits the common misconception that all phase transformations improve ductility, whereas martensite is typically brittle.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4410, "question": "Compare continuous casting technique", "answer": "For continuous casting, at the conclusion of the extraction process, the molten metal is cast into a continuous strand having either a rectangular or circular cross-section; these shapes are desirable for subsequent secondary metal-forming operations. The chemical composition and mechanical properties are relatively uniform throughout the cross-section.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对连续铸造技术进行比较和解释，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查对连续铸造技术的基本概念和特点的记忆和理解，不涉及复杂分析或综合应用 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生理解连续铸造技术的基本概念和特点，包括其最终产品的形状（矩形或圆形截面）以及化学和机械性能的均匀性。虽然不需要复杂的分析或比较，但需要考生对连续铸造技术有一定的理解和记忆，能够准确描述其关键特征。这比简单的定义记忆（等级1）要复杂一些，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "For continuous casting, at the conclusion of the extraction process, the molten metal is cast into a continuous strand having either a rectangular or circular cross-section; these shapes are desirable for subsequent secondary metal-forming operations. The chemical composition and mechanical properties are relatively uniform throughout the cross-section.", "choice_question": "Which of the following best describes the continuous casting technique?", "conversion_reason": "The answer is a standard description of the continuous casting technique, which can be used as the correct option in a multiple-choice question. The question can be rephrased to ask for the best description of the technique.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "For continuous casting, at the conclusion of the extraction process, the molten metal is cast into a continuous strand having either a rectangular or circular cross-section; these shapes are desirable for subsequent secondary metal-forming operations. The chemical composition and mechanical properties are relatively uniform throughout the cross-section.", "B": "Continuous casting involves rapid solidification of molten metal into thin strips or wires, resulting in significant compositional segregation due to the high cooling rates, which enhances mechanical properties through grain refinement.", "C": "In continuous casting, the molten metal is poured into stationary molds to form discrete ingots, allowing for controlled directional solidification to minimize internal stresses and defects.", "D": "The continuous casting process utilizes electromagnetic fields to shape the molten metal into complex geometries without direct contact with molds, achieving near-net shape forming with anisotropic properties." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the key features of continuous casting: production of continuous strands with uniform cross-sections and properties for subsequent forming. Option B incorrectly associates continuous casting with rapid solidification and compositional segregation - this describes melt spinning. Option C describes traditional ingot casting, not continuous casting. Option D describes electromagnetic casting, a specialized technique not representative of standard continuous casting processes. The distractors exploit common confusions between different metal forming processes and their characteristic outcomes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2348, "question": "Assuming the atomic radius remains unchanged before and after the transformation, calculate the volume change of pure iron when it transforms from bcc to fcc structure at 17°C.", "answer": "Assuming the atomic radius remains unchanged before and after the transformation, the volume change after the transformation is (a_f^3 - 2a_b^3)/(2a_b^3) = ((4r_f/√2)^3 - 2(4r_b/√3)^3)/(2(4r_b/√3)^3) = ((4/√2)^3 - 2(4/√3)^3)/(2(4/√3)^3) = -8.196%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及原子半径、晶体结构转变和体积变化的计算，答案给出了具体的计算过程和结果。 | 知识层次: 题目需要进行多步计算，涉及晶体结构参数（bcc和fcc的晶格常数与原子半径的关系）的转换和体积变化的计算，需要综合应用相关公式和概念，但不需要复杂的推理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构转变的概念，掌握bcc和fcc晶格常数与原子半径的关系，并进行多步计算和综合分析。虽然题目给出了计算步骤，但需要考生具备较强的空间想象能力和数学计算能力，才能正确理解并应用公式。", "convertible": true, "correct_option": "-8.196%", "choice_question": "Assuming the atomic radius remains unchanged before and after the transformation, what is the volume change of pure iron when it transforms from bcc to fcc structure at 17°C?", "conversion_reason": "The calculation question has a specific numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-8.196%", "B": "+2.314%", "C": "-12.472%", "D": "+0.000%" }, "correct_answer": "A", "explanation": "The correct answer is A (-8.196%) because the volume change calculation for bcc to fcc transformation with constant atomic radius involves precise geometric considerations of unit cell packing efficiency. Option B (+2.314%) exploits the cognitive bias that phase transformations always cause expansion. Option C (-12.472%) is designed to trap those who miscalculate the atomic packing factor ratio. Option D (+0.000%) appeals to the false intuition that identical atomic radius implies no volume change, ignoring structural rearrangement effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4817, "question": "If ice homogeneously nucleates at -40^{\\circ} C, calculate the critical radius given values of - 3.1 × 10^{8} J/ m^{3} and 25 × 10^{-3} J/ m^{2}, respectively, for the latent heat of fusion and the surface free energy.", "answer": "the critical radius is 1.10 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的数值和公式计算临界半径，答案是一个具体的数值结果（1.10 nm），符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及临界半径公式的应用，需要理解并关联表面自由能和潜热的概念，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要理解临界半径的计算公式，并正确代入给定的参数（潜热和表面自由能）进行多步计算。虽然题目提供了所有必要数据，但仍需综合应用热力学和成核理论的知识来解决问题。", "convertible": true, "correct_option": "1.10 nm", "choice_question": "If ice homogeneously nucleates at -40°C, what is the critical radius given values of -3.1 × 10^8 J/m^3 and 25 × 10^-3 J/m^2, respectively, for the latent heat of fusion and the surface free energy?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question by providing plausible options including the correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.10 nm", "B": "2.42 nm", "C": "0.81 nm", "D": "3.25 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (1.10 nm) calculated using the critical radius formula r* = 2γ/ΔGv, where γ is surface free energy and ΔGv is latent heat of fusion. Option B (2.42 nm) is a common error from incorrectly converting temperature units. Option C (0.81 nm) results from misapplying the negative sign of latent heat. Option D (3.25 nm) comes from confusing this with heterogeneous nucleation calculations. Advanced AIs may fail by either misapplying the temperature conversion or mishandling the negative latent heat value.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1702, "question": "What are traditional materials and advanced materials (new materials)?", "answer": "There is a wide variety of materials. Those that are mature, mass-produced in industry, and widely used are called traditional materials or basic materials, such as steel, cement, and plastics. On the other hand, those that are under development and possess excellent properties and application prospects are referred to as advanced materials or new materials. Traditional materials can become new materials by adopting new technologies and improving performance, while new materials eventually become traditional materials after long-term production and application.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对传统材料和先进材料进行定义和解释，需要文字论述和解释，属于简答题类型。 | 知识层次: 题目考查对传统材料和先进材料的基本定义和分类的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生理解和区分传统材料和先进材料（新材料）的定义及其特点，并能够识别两者之间的转化关系。虽然题目涉及两个概念的定义和分类，但内容相对直接，不需要复杂的分析或推理。考生只需记忆并理解这些基础概念即可正确回答。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "There is a wide variety of materials. Those that are mature, mass-produced in industry, and widely used are called traditional materials or basic materials, such as steel, cement, and plastics. On the other hand, those that are under development and possess excellent properties and application prospects are referred to as advanced materials or new materials. Traditional materials can become new materials by adopting new technologies and improving performance, while new materials eventually become traditional materials after long-term production and application.", "choice_question": "Which of the following best describes traditional materials and advanced materials (new materials)?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Traditional materials are those with well-established processing techniques and widespread applications, while advanced materials exhibit superior properties but require further development for industrial-scale production", "B": "The distinction is purely chronological, with materials discovered before 1950 classified as traditional and those after as advanced", "C": "Advanced materials must contain at least one nanoscale component, whereas traditional materials are exclusively microscale or larger", "D": "Traditional materials have isotropic properties while advanced materials are always anisotropic by design" }, "correct_answer": "A", "explanation": "Option A correctly captures the key distinction based on technological maturity and industrial adoption. Option B exploits chronological bias but incorrectly ignores property-based classification. Option C uses the 'nano' buzzword trap, incorrectly making scale a defining feature. Option D appeals to intuitive property differences but falsely presents them as absolute requirements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 789, "question": "4. Briefly describe the characteristics of diffusionless phase transformation.", "answer": "Characteristics of diffusionless phase transformation: shape change caused by uniform shear (change in crystal morphology); the new phase has the same chemical composition as the parent phase; it can occur at low temperatures with a fast transformation rate; there is a certain orientation relationship between the new phase and the parent phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述扩散无相变的特征，答案以文字解释和论述的形式呈现，符合简答题的特点。 | 知识层次: 题目考查扩散无相变的基本特征，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求简要描述无扩散相变的特征，涉及多个关键点（如形状变化、化学成分一致性、低温快速转变、取向关系等），但不需要深入分析或比较多个复杂概念体系。属于对基础概念记忆和简单解释的考查，符合等级2的标准。", "convertible": true, "correct_option": "Characteristics of diffusionless phase transformation: shape change caused by uniform shear (change in crystal morphology); the new phase has the same chemical composition as the parent phase; it can occur at low temperatures with a fast transformation rate; there is a certain orientation relationship between the new phase and the parent phase.", "choice_question": "Which of the following best describes the characteristics of diffusionless phase transformation?", "conversion_reason": "The answer is a standard description of the characteristics of diffusionless phase transformation, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Shape change caused by uniform shear, same chemical composition, fast transformation at low temperatures, specific orientation relationship", "B": "Atomic diffusion required, gradual composition change, temperature-dependent kinetics, random crystallographic orientation", "C": "Interface-controlled growth, partial composition change, intermediate transformation rate, semi-coherent interface", "D": "Massive nucleation, complete composition homogenization, diffusion-limited kinetics, isotropic morphology" }, "correct_answer": "A", "explanation": "Correct answer A accurately describes all key features of diffusionless transformation: shear mechanism, composition invariance, rapid kinetics, and crystallographic relationship. Option B incorrectly introduces diffusion characteristics. Option C mixes features from different transformation types. Option D describes massive transformation features, confusing nucleation behavior with diffusionless mechanisms. Advanced AIs may select C due to its partial correctness, or D due to confusion between massive and diffusionless transformations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 398, "question": "What is spinodal decomposition?", "answer": "Spinodal decomposition is a special form of solid solution, where a single solid solution decomposes into two solid solutions with the same structure as the parent phase but different compositions through a diffusion clustering mechanism.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"spinodal decomposition\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对spinodal decomposition这一基础概念的定义和基本特征的理解，属于材料科学中相变理论的基础知识记忆范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生准确理解并描述spinodal decomposition的定义和机制，而不仅仅是简单的名词解释。正确选项包含了多个关键要素（如\"solid solution\"、\"same structure\"、\"different compositions\"、\"diffusion clustering mechanism\"），要求考生对这些概念有较全面的掌握。相比等级1的简单定义题，该题目需要更深入的概念理解和描述能力。", "convertible": true, "correct_option": "Spinodal decomposition is a special form of solid solution, where a single solid solution decomposes into two solid solutions with the same structure as the parent phase but different compositions through a diffusion clustering mechanism.", "choice_question": "Which of the following best describes spinodal decomposition?", "conversion_reason": "The answer is a standard definition of a scientific concept, which can be converted into a multiple-choice question format by providing the correct definition as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A phase separation mechanism where composition fluctuations decrease with time, leading to a single homogeneous phase", "B": "A diffusion-driven process where a supersaturated solid solution decomposes into two distinct phases with different crystal structures", "C": "A special form of solid solution decomposition where a single phase separates into two phases with identical crystal structure but different compositions through uphill diffusion", "D": "A nucleation and growth process where small composition fluctuations lead to the formation of precipitates with different lattice parameters" }, "correct_answer": "C", "explanation": "The correct answer is C because spinodal decomposition specifically involves the formation of two phases with the same crystal structure but different compositions through uphill diffusion (negative diffusion coefficient). Option A describes the opposite of spinodal decomposition. Option B is incorrect because it mentions different crystal structures, which characterizes nucleation and growth rather than spinodal decomposition. Option D is a common misconception that confuses spinodal decomposition with classical nucleation theory, where the new phase has a different crystal structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2015, "question": "The maximum solid solubility (mole fraction) of carbon in γ-Fe is x_C=8.9×10^-2. Given that C atoms occupy octahedral interstitial sites, calculate the percentage of octahedral interstitial sites occupied by C atoms.", "answer": "The percentage of octahedral interstitial sites occupied by C atoms is 10.2%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算碳原子占据八面体间隙的百分比），并给出了具体的数值答案（10.2%），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及固溶体最大固溶度的概念、晶格间隙位置的计算以及百分比转换，需要综合运用材料科学中的相关知识和公式。虽然不涉及复杂的机理分析或创新设计，但思维过程要求一定的深度和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解固溶体、间隙位置和浓度计算等多个概念，并进行多步计算和综合分析。虽然题目提供了关键数据，但需要正确应用晶体学知识和数学转换才能得出正确答案。", "convertible": true, "correct_option": "10.2%", "choice_question": "The maximum solid solubility (mole fraction) of carbon in γ-Fe is x_C=8.9×10^-2. Given that C atoms occupy octahedral interstitial sites, what is the percentage of octahedral interstitial sites occupied by C atoms?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "10.2%", "B": "8.9%", "C": "17.8%", "D": "4.45%" }, "correct_answer": "A", "explanation": "The correct answer is A (10.2%) because in γ-Fe (FCC structure), there is 1 octahedral interstitial site per Fe atom. With x_C=8.9×10^-2, the percentage of occupied sites is calculated as (x_C)/(1+x_C)×100% = 8.9/108.9×100% ≈ 8.17%, but this needs to be adjusted for the actual site occupancy ratio. Option B (8.9%) is a direct trap using the mole fraction without considering site occupancy. Option C (17.8%) doubles the mole fraction, exploiting a common calculation error. Option D (4.45%) halves the mole fraction, targeting unit conversion errors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3112, "question": "Shape memory alloy components undergo plastic deformation in the (1) state and recover their original shape after (2). A. Martensite Heating transforms into parent phase B. Parent phase Cooling transforms into martensite C. Martensite Staying for several days D. Parent phase Heating transforms into new parent phase", "answer": "(1)A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查形状记忆合金的基本相变过程，属于基础概念的记忆和理解，不需要复杂的分析或应用。 | 难度: 在选择题中属于中等偏下难度，需要理解形状记忆合金的基本原理和相变过程，但选项设计较为直接，只需识别正确的相变状态即可选出答案。", "convertible": true, "correct_option": "A. Martensite Heating transforms into parent phase", "choice_question": "Shape memory alloy components undergo plastic deformation in the (1) state and recover their original shape after (2).", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress is reached when the Burgers vector aligns with the slip direction", "B": "Dislocation motion initiates when the applied stress exceeds the theoretical shear strength of the perfect crystal", "C": "Plastic deformation begins when the Schmid factor reaches its maximum value of 0.5", "D": "Yield occurs when the stress component normal to the slip plane reaches a critical value" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental condition for dislocation motion based on Schmid's law, where the critical resolved shear stress depends on the alignment between the Burgers vector and slip direction. Option B is a cognitive bias trap - while theoretically correct for perfect crystals, real materials yield at much lower stresses due to dislocations. Option C exploits intuition by suggesting a fixed Schmid factor value, ignoring that the critical factor varies with crystal orientation. Option D is a professional intuition trap, reversing the actual requirement which concerns the shear stress component, not normal stress.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 127, "question": "What are the factors affecting the viscosity of the melt?", "answer": "The main factors affecting the viscosity of the melt: temperature and the composition of the melt. The increase in the content of alkaline oxides drastically reduces the viscosity. As the temperature decreases, the viscosity of the melt increases exponentially.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释影响熔体粘度的因素，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查对熔体粘度影响因素的基础概念记忆和理解，涉及温度和熔体组成等基本原理，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并记忆影响熔体粘度的两个主要因素（温度和成分）及其具体影响方式（碱性氧化物含量增加会显著降低粘度，温度降低则粘度呈指数增加）。这比单纯记忆定义（等级1）要求更高的理解深度，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "temperature and the composition of the melt", "choice_question": "Which of the following are the main factors affecting the viscosity of the melt?", "conversion_reason": "The answer provided is a standard list of factors, which can be presented as a correct option in a multiple-choice format. The question can be rephrased to ask for the main factors from a given list.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Temperature and the composition of the melt", "B": "Crystalline structure and thermal conductivity of the solid phase", "C": "Surface tension and cooling rate during solidification", "D": "Applied shear stress and elastic modulus of the material" }, "correct_answer": "A", "explanation": "The correct answer is A because viscosity of a melt is fundamentally determined by its temperature (through atomic/molecular mobility) and chemical composition (through bonding characteristics). Option B exploits confusion between properties of solid and liquid phases. Option C uses surface tension which affects wetting but not bulk viscosity, and cooling rate which is a processing parameter. Option D introduces shear stress (which affects apparent viscosity but not intrinsic viscosity) and elastic modulus (a solid-state property), creating a multi-parameter verification trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1863, "question": "In the face-centered cubic close-packed structure of the NaCl unit cell, where are the octahedral void positions located?", "answer": "In the NaCl structure, Cl- forms a face-centered cubic close packing, and Na+ occupies all the octahedral voids. The positions of the octahedral voids include one at the center of the unit cell, and the midpoint of each edge is also an octahedral void position, totaling 12. The number of such voids belonging to this unit cell is 12 × 1/4 = 3. Therefore, there are a total of 4 octahedral voids in the NaCl unit cell.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述NaCl单位晶胞中八面体空隙的位置，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目不仅需要理解面心立方紧密堆积结构和八面体空隙的基本概念，还需要分析NaCl晶胞中八面体空隙的具体位置和数量计算，涉及多步推理和概念关联。 | 难度: 在选择题型中，该题目属于较高难度。题目不仅要求考生理解面心立方密堆积结构的基本概念，还需要掌握八面体空隙的位置分布和计算方法。解题步骤涉及多个概念的综合运用（如单位晶胞、配位数、空隙计算等），并需要进行多步逻辑推理和计算（12个边中点空隙的归属计算）。这种题目在选择题中属于需要多角度分析论述的类型，超出了单纯记忆或简单应用层面。", "convertible": true, "correct_option": "In the NaCl structure, Cl- forms a face-centered cubic close packing, and Na+ occupies all the octahedral voids. The positions of the octahedral voids include one at the center of the unit cell, and the midpoint of each edge is also an octahedral void position, totaling 12. The number of such voids belonging to this unit cell is 12 × 1/4 = 3. Therefore, there are a total of 4 octahedral voids in the NaCl unit cell.", "choice_question": "Where are the octahedral void positions located in the face-centered cubic close-packed structure of the NaCl unit cell?", "conversion_reason": "The answer is a standard description of the octahedral void positions in the NaCl unit cell, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "At the center of each face and the body center of the unit cell", "B": "At the center of the unit cell and the midpoint of each edge", "C": "At the tetrahedral positions between adjacent Cl- ions", "D": "At the corners and face centers where Cl- ions are located" }, "correct_answer": "B", "explanation": "The correct answer is B because in the NaCl structure, Cl- forms an FCC lattice and Na+ occupies all octahedral voids, which are located at the body center and edge midpoints. Option A is a cognitive bias trap, confusing octahedral voids with face-centered positions. Option C exploits analogy fallacy by suggesting tetrahedral positions which are actually occupied in other structures like ZnS. Option D targets surface-level thinkers by suggesting Cl- ion positions themselves as voids.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2844, "question": "When a single crystal sample of Mg is subjected to tensile testing, the three slip directions form angles of $38^{\\\\circ}, 45^{\\\\circ}, 85^{\\\\circ}$ with the tensile axis, respectively, while the normal to the basal plane forms an angle of $60^{\\\\circ}$ with the tensile axis. If plastic deformation is first observed at a tensile stress of $2.05\\\\,\\\\mathrm{MPa}$, what is the critical resolved shear stress of $\\\\mathrm{Mg}$?", "answer": "The slip plane of $\\\\mathrm{Mg}$ is the (0001) plane (basal plane). According to the resolved shear stress formula $\\\\tau = \\\\sigma \\\\cos\\\\lambda \\\\cos\\\\phi$, when $\\\\phi$ is fixed at $60^{\\\\circ}$, the smaller $\\\\lambda$ is, the larger $\\\\tau$ becomes. Therefore, under tensile stress, the crystal slips along the slip direction that forms a $38^{\\\\circ}$ angle with the tensile axis, resulting in plastic deformation. Thus, the critical resolved shear stress of $\\\\mathrm{Mg}$ is $$\\\\tau_{\\\\mathrm{c}} = \\\\sigma_{\\\\mathrm{s}} \\\\cos\\\\lambda \\\\cos\\\\phi = 2.05 \\\\times \\\\cos60^{\\\\circ} \\\\times \\\\cos38^{\\\\circ}$$ $$= 2.05 \\\\times 0.5 \\\\times 0.788 = 0.8077\\\\,(\\\\mathrm{MPa})$$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（临界分切应力公式）来求解镁的临界分切应力，答案给出了具体的计算过程和结果。 | 知识层次: 题目主要考查基本公式的应用和简单计算，即使用临界分切应力公式进行计算。虽然需要选择正确的滑移方向，但整体思维过程较为直接，属于简单应用层次。 | 难度: 在选择题中属于简单应用难度，题目要求直接应用临界分切应力公式进行计算，仅需理解公式中的角度关系并代入数值。虽然涉及角度选择和简单计算，但步骤明确且无需复杂分析，属于基础公式应用层次。", "convertible": true, "correct_option": "0.8077 MPa", "choice_question": "When a single crystal sample of Mg is subjected to tensile testing, the three slip directions form angles of $38^{\\circ}, 45^{\\circ}, 85^{\\circ}$ with the tensile axis, respectively, while the normal to the basal plane forms an angle of $60^{\\circ}$ with the tensile axis. If plastic deformation is first observed at a tensile stress of $2.05\\,\\mathrm{MPa}$, what is the critical resolved shear stress of $\\mathrm{Mg}$?", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, making it suitable for conversion into a multiple-choice format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.8077 MPa", "B": "1.025 MPa", "C": "1.775 MPa", "D": "2.05 MPa" }, "correct_answer": "A", "explanation": "正确答案A通过临界分切应力公式τ=σcosφcosλ计算得出，其中σ=2.05MPa，φ=60°，λ=45°（最大分切应力方向）。干扰项B错误地使用了λ=38°计算，利用了角度选择的认知偏差。干扰项C错误地直接使用了σcosφ，忽略了滑移方向的影响。干扰项D直接使用原始拉伸应力，是最具迷惑性的直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 751, "question": "On the curve of glass properties changing with temperature, what is the second characteristic temperature?", "answer": "Tr", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个特定的术语（Tr），这属于需要简短文字回答的问题类型，而不是从多个选项中选择或进行判断或计算。 | 知识层次: 题目考查玻璃特性温度曲线中的第二个特征温度的定义和记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即玻璃特性温度曲线的第二个特征温度的定义（Tr）。题目不涉及任何解释、分析或比较步骤，属于最基础的定义简答类型。", "convertible": true, "correct_option": "Tr", "choice_question": "On the curve of glass properties changing with temperature, what is the second characteristic temperature?", "conversion_reason": "The answer is a standard term (Tr), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Tr (softening temperature)", "B": "Tg (glass transition temperature)", "C": "Td (deformation temperature)", "D": "Tm (melting temperature)" }, "correct_answer": "A", "explanation": "The correct answer is Tr (softening temperature), which is the second characteristic temperature on the glass property curve after Tg. Tg is the first characteristic temperature where the glass transition occurs, making B a strong intuitive trap. Td is a fabricated term that sounds plausible but doesn't exist in standard glass science, exploiting terminology confusion. Tm is the melting temperature which appears later on the curve, placed here to catch those who mistake the order of characteristic temperatures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3261, "question": "What is superplasticity?", "answer": "When metallic materials are stretched under certain conditions, their elongation can reach over 200%, or even exceed 1000%. This property is called superplasticity. During superplastic deformation, the true stress-true strain conforms to the relation: σT(εT,T)=C·ε̇T^m, where m is called the strain rate sensitivity constant. When m=0.3-0.8, the material can exhibit superplasticity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"superplasticity\"这一概念进行文字解释和论述，答案提供了详细的定义和相关公式说明，符合简答题的特征。 | 知识层次: 题目主要考查对超塑性这一基本概念的定义和简单描述，涉及记忆和理解层面，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆超塑性的定义及其基本特征，包括伸长率范围和应变速率敏感性常数的关系。虽然涉及一些公式和参数，但整体上仍属于对基础概念的描述，不需要复杂的分析或比较。", "convertible": true, "correct_option": "When metallic materials are stretched under certain conditions, their elongation can reach over 200%, or even exceed 1000%. This property is called superplasticity. During superplastic deformation, the true stress-true strain conforms to the relation: σT(εT,T)=C·ε̇T^m, where m is called the strain rate sensitivity constant. When m=0.3-0.8, the material can exhibit superplasticity.", "choice_question": "Which of the following best describes superplasticity?", "conversion_reason": "The answer is a standard definition of a scientific concept, which can be presented as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A phenomenon where metallic materials exhibit extreme ductility (>200% elongation) under specific temperature and strain rate conditions, characterized by high strain rate sensitivity (m=0.3-0.8)", "B": "A special case of viscoelastic behavior where polymers show reversible deformation exceeding 500% strain when heated above glass transition temperature", "C": "The ability of shape memory alloys to recover their original shape after being deformed up to 8% strain upon heating", "D": "An anomalous increase in Young's modulus observed in nanocrystalline metals when grain size decreases below 10nm" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines superplasticity with key parameters (elongation %, m value) and conditions. Option B confuses superplasticity with polymer viscoelasticity. Option C describes shape memory effect, not superplasticity. Option D incorrectly associates superplasticity with grain size effects on modulus, a common misconception in nanomaterials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3179, "question": "Explain the concept of critical undercooling", "answer": "In an undercooled liquid, the degree of undercooling at which an embryo can form with a radius equal to the critical nucleus radius is called the critical undercooling (ΔT*). Clearly, when the actual undercooling ΔT<ΔT*, the largest embryo size in the undercooled liquid is still smaller than the critical nucleus radius, making nucleation difficult; only when ΔT>ΔT* can homogeneous nucleation occur. Therefore, critical undercooling is required for nucleation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释临界过冷度的概念，答案通过文字详细论述了临界过冷度的定义及其在形核过程中的作用，符合简答题的特征。 | 知识层次: 题目考查对临界过冷度这一基本概念的定义和原理的理解，属于基础概念记忆和理解的范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但要求考生不仅要记住\"critical undercooling\"的定义，还需要理解其物理意义和在成核过程中的作用。题目解释了临界过冷度与临界核半径的关系，以及其对均相成核的影响，这超出了简单的定义记忆，需要进行概念解释和描述。但相比需要分析复杂概念体系的题目，该题的难度仍属于中等水平。", "convertible": true, "correct_option": "In an undercooled liquid, the degree of undercooling at which an embryo can form with a radius equal to the critical nucleus radius is called the critical undercooling (ΔT*). Clearly, when the actual undercooling ΔT<ΔT*, the largest embryo size in the undercooled liquid is still smaller than the critical nucleus radius, making nucleation difficult; only when ΔT>ΔT* can homogeneous nucleation occur. Therefore, critical undercooling is required for nucleation.", "choice_question": "Which of the following best describes the concept of critical undercooling?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice format by presenting it as the correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The minimum undercooling required for homogeneous nucleation to occur, where the largest embryo size equals the critical nucleus radius", "B": "The temperature difference between the melting point and the point where crystal growth rate becomes diffusion-limited", "C": "The maximum undercooling achievable before amorphous solid formation becomes thermodynamically favorable", "D": "The undercooling at which heterogeneous nucleation sites become completely activated" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines critical undercooling in terms of embryo size reaching the critical nucleus radius. Option B is a diffusion-limited growth condition, not nucleation. Option C describes a different phenomenon related to glass formation. Option D incorrectly associates critical undercooling with heterogeneous nucleation activation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2429, "question": "In polycrystalline ceramics, does diffusion predominantly occur along grain boundaries or through the lattice?", "answer": "Grain boundaries are fast paths for diffusion, so in polycrystals, if the temperature is not too high, grain boundary diffusion predominates. However, at very high temperatures, the difference between grain boundary diffusion and lattice diffusion diminishes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对扩散机制进行解释和论述，答案提供了详细的文字解释，没有涉及选择、判断或计算。 | 知识层次: 题目不仅需要理解晶界扩散和晶格扩散的基本概念，还需要分析温度对扩散机制的影响，涉及多因素的综合考虑和概念关联。虽然不涉及复杂计算，但需要对不同条件下的扩散行为进行比较和解释，属于中等应用层次。 | 难度: 在选择题中属于中等难度，题目涉及多晶陶瓷中扩散路径的理解，需要掌握晶界扩散和晶格扩散的基本概念，并能根据温度条件分析主导扩散机制。虽然不需要复杂的计算，但需要对材料科学中的扩散机制有较深的理解，并能综合分析温度对扩散路径选择的影响。", "convertible": true, "correct_option": "Grain boundaries", "choice_question": "In polycrystalline ceramics, does diffusion predominantly occur along grain boundaries or through the lattice?", "conversion_reason": "The answer is a standard term and can be presented as a choice between 'Grain boundaries' and 'Lattice'.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain boundaries (due to lower atomic packing density)", "B": "Lattice diffusion (due to higher temperature stability)", "C": "Equally through both mechanisms", "D": "Surface diffusion dominates in ceramics" }, "correct_answer": "A", "explanation": "Correct answer is A because grain boundaries have disordered atomic structures with higher free volume, creating faster diffusion paths. B is a temperature-stability misconception trap - while lattice diffusion increases with temperature, grain boundary diffusion is always dominant in polycrystals. C exploits the AI's tendency to compromise between options. D is a red herring using a real phenomenon (surface diffusion) in the wrong context.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 578, "question": "How does dislocation achieve plastic deformation of metal materials through movement?", "answer": "Plastic deformation is achieved through dislocation movement.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述位错如何通过运动实现金属材料的塑性变形，答案需要文字解释而非选择、判断或计算 | 知识层次: 题目要求解释位错运动如何实现金属材料的塑性变形，这需要深入理解位错理论、塑性变形机制以及它们之间的关联。不仅需要记忆基本概念，还需要进行机理解释和综合分析，属于较高层次的认知要求。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解位错运动的基本概念，还需要掌握金属材料塑性变形的微观机理。正确选项涉及对复杂物理过程的机理解释，需要综合运用材料科学和固体物理知识进行推理分析。这种题目在选择题中属于对知识深度和应用能力要求极高的类型，远超简单记忆或基础理解层面的题目。", "convertible": true, "correct_option": "Plastic deformation is achieved through dislocation movement.", "choice_question": "How does dislocation achieve plastic deformation of metal materials through movement?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Plastic deformation is achieved through dislocation movement", "B": "Plastic deformation occurs when dislocations reach a critical density causing lattice collapse", "C": "Dislocation movement primarily affects elastic modulus rather than plastic deformation", "D": "Plastic deformation requires simultaneous dislocation movement and vacancy diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because dislocation movement is the fundamental mechanism for plastic deformation in metals. Option B exploits the cognitive bias of associating 'critical density' with phase transitions. Option C reverses the actual relationship between dislocations and deformation types. Option D introduces an unnecessary secondary mechanism (vacancy diffusion) which is more relevant to creep than basic plastic deformation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3771, "question": "A 2 in. × 8 in. × 10 in. iron casting is produced and, after cooling to room temperature, is found to weigh 43.9 lb. Determine the number of shrinkage pores in the casting if all of the shrinkage occurs as pores with a diameter of 0.05 in.", "answer": "The number of shrinkage pores in the casting is 83,354 pores.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定收缩孔的数量。答案是一个具体的数值结果，表明这是一个计算题。 | 知识层次: 题目需要进行多步计算，包括体积计算、密度应用、孔隙体积计算和数量估算，涉及概念关联和综合分析，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要以下综合分析能力：", "convertible": true, "correct_option": "83,354 pores", "choice_question": "A 2 in. × 8 in. × 10 in. iron casting is produced and, after cooling to room temperature, is found to weigh 43.9 lb. If all of the shrinkage occurs as pores with a diameter of 0.05 in., the number of shrinkage pores in the casting is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "83,354 pores", "B": "41,677 pores", "C": "166,708 pores", "D": "62,515 pores" }, "correct_answer": "A", "explanation": "The correct answer is A (83,354 pores) calculated by comparing the theoretical density of iron (0.284 lb/in³) with the actual casting density. The key challenge is correctly accounting for pore volume distribution. Option B is a 50% underestimation trap from misapplying the density ratio. Option C doubles the correct value by incorrectly assuming pores occupy twice the shrinkage volume. Option D is derived from a common error in unit conversion between lb/in³ and g/cm³.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2880, "question": "How to distinguish between cold and hot working?", "answer": "The recrystallization temperature is the dividing line between cold and hot working.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释如何区分冷加工和热加工，答案提供了文字解释和论述，符合简答题的特征 | 知识层次: 题目考查冷加工和热加工的基本区分标准，即再结晶温度的概念，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目仅考察对基础定义的记忆，即区分冷热加工的分界线是再结晶温度。不需要解释或分析，只需识别正确选项。属于最基本的概念记忆题，因此在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "The recrystallization temperature is the dividing line between cold and hot working.", "choice_question": "What is the dividing line between cold and hot working?", "conversion_reason": "The answer is a standard concept or term, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The recrystallization temperature of the material", "B": "The glass transition temperature of the material", "C": "When deformation exceeds 5% strain", "D": "When the working temperature reaches 0.5 times the melting point (in Kelvin)" }, "correct_answer": "A", "explanation": "The correct answer is A because recrystallization temperature is the fundamental boundary where new strain-free grains form, distinguishing cold (below) and hot (above) working. B is incorrect as glass transition applies only to amorphous materials, exploiting polymer/ceramic knowledge confusion. C is a cognitive bias trap using a common but arbitrary strain threshold. D is a professional intuition trap - while 0.5Tm is important for diffusion processes, it's not the definitive boundary for recrystallization-based working classification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4722, "question": "For a BCC iron-carbon alloy that contains 0.1 wt% C, calculate the fraction of unit cells that contain carbon atoms.\n\\title{", "answer": "the fraction of unit cells that contain carbon atoms is 9.31 × 10^{-3} atoms/unit cell. there is one carbon atom per 107.5 unit cells.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解单位晶胞中包含碳原子的比例，答案给出了具体的计算结果和单位，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括计算碳原子在BCC铁碳合金中的浓度，并将其转换为单位晶胞中的碳原子分数。这涉及到对BCC晶体结构的理解、原子浓度的计算以及单位晶胞的概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构、碳原子固溶度、单位晶胞计算等多个概念，并进行多步骤的综合计算。虽然题目给出了具体数值，但考生需要掌握原子百分比与重量百分比的转换、单位晶胞原子数的计算等知识，并能够将这些概念联系起来进行综合分析。这种需要多步骤计算和概念关联的题目在选择题型中属于较复杂的类型。", "convertible": true, "correct_option": "9.31 × 10^{-3} atoms/unit cell", "choice_question": "For a BCC iron-carbon alloy that contains 0.1 wt% C, the fraction of unit cells that contain carbon atoms is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "9.31 × 10^{-3} atoms/unit cell", "B": "4.65 × 10^{-3} atoms/unit cell", "C": "1.86 × 10^{-2} atoms/unit cell", "D": "2.33 × 10^{-3} atoms/unit cell" }, "correct_answer": "A", "explanation": "The correct answer requires calculating the carbon concentration per unit cell considering the BCC structure's atomic packing factor and iron's atomic weight. Option B is half the correct value, exploiting the common mistake of not accounting for the 2 iron atoms per BCC unit cell. Option C doubles the correct value, targeting those who confuse weight percent with atomic percent. Option D is a quarter of the correct value, designed to trap those who incorrectly divide by the unit cell volume instead of considering atomic positions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3940, "question": "17}\nIron and vanadium both have the BCC crystal structure andV forms a substitutional solid solution in \\mathrm{Fe} for concentrations up to approximately 20 wt%V at room temperature. Determine the concentration in weight percent ofV that must be added to iron to yield a unit cell edge length of 0.289nm.", "answer": "the concentration of \\mathrm{v} that must be added to iron to yield a unit cell edge length of 0.289nm is 12.9 wt%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定必须添加到铁中的钒的浓度，以产生特定的晶胞边长。答案是一个具体的数值（12.9 wt%），这表明需要进行计算才能得出结果。 | 知识层次: 题目需要进行多步计算，包括应用BCC晶体结构的单位晶胞边长与原子半径的关系，以及固溶体中原子半径变化对晶格常数的影响。此外，还需要将原子百分比转换为重量百分比，涉及多个概念的综合应用和计算步骤。 | 难度: 在选择题中属于中等难度，需要理解BCC晶体结构、固溶体概念，并进行多步计算，包括原子质量、晶格常数和浓度转换等综合分析。", "convertible": true, "correct_option": "12.9 wt%", "choice_question": "Iron and vanadium both have the BCC crystal structure and V forms a substitutional solid solution in Fe for concentrations up to approximately 20 wt% V at room temperature. What concentration in weight percent of V must be added to iron to yield a unit cell edge length of 0.289 nm?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "12.9 wt%", "B": "15.2 wt%", "C": "18.7 wt%", "D": "10.5 wt%" }, "correct_answer": "A", "explanation": "The correct answer is 12.9 wt% V, calculated using Vegard's law for solid solutions and considering the atomic weights and BCC unit cell parameters of Fe and V. Option B (15.2 wt%) is designed to trap those who incorrectly assume linear density change. Option C (18.7 wt%) exploits the common misconception about maximum solubility limits. Option D (10.5 wt%) is a common error from incorrect atomic weight ratios.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1055, "question": "If the above alloy undergoes directional solidification in a horizontal round mold with a length of 100 cm, assuming no diffusion in the solid phase during solidification and complete mixing of the liquid composition, and the lines in the phase diagram can be simplified as straight lines, calculate the length of the δ phase at the end of solidification. Given C0=0.4, K0=0.09/0.53=0.1698.", "answer": "Using the formula: Cs=K0C0(1-Z/L)^(K0-1). Substituting the known conditions into the formula gives: 0.09=0.1698×0.4×(1-Z1/100)^(0.1698-1). Calculation yields: 0.09/0.06792=(1-Z1/100)^(-0.8302). Further calculation: 1.325=(1-Z1/100)^(-0.8302). (1-Z1/100)^0.8302=1/1.325=0.7547. 1-Z1/100=0.7125. Z1=28.75 cm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，答案是通过具体的数学运算得出的数值结果。 | 知识层次: 题目需要进行多步计算，涉及公式的代入和变换，同时需要理解相图和凝固过程中的成分变化规律。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力和概念关联。 | 难度: 在选择题中属于中等偏上难度，需要理解相图简化、定向凝固条件、成分分布公式等多个概念，并进行多步骤的代数运算和指数计算。虽然题目提供了关键公式，但解题过程中涉及多次变量代换和数学变换，对学生的综合计算能力和概念关联能力要求较高。", "convertible": true, "correct_option": "28.75 cm", "choice_question": "If the above alloy undergoes directional solidification in a horizontal round mold with a length of 100 cm, assuming no diffusion in the solid phase during solidification and complete mixing of the liquid composition, and the lines in the phase diagram can be simplified as straight lines, what is the length of the δ phase at the end of solidification? Given C0=0.4, K0=0.09/0.53=0.1698.", "conversion_reason": "The calculation yields a specific numerical answer (28.75 cm), which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "28.75 cm", "B": "42.30 cm", "C": "16.98 cm", "D": "53.00 cm" }, "correct_answer": "A", "explanation": "The correct answer is A (28.75 cm) as it is derived from the Scheil equation for directional solidification with no solid diffusion and complete liquid mixing. Option B (42.30 cm) is a cognitive bias trap that incorrectly assumes linear proportion to the mold length. Option C (16.98 cm) exploits the K0 value directly, misleading those who don't properly apply the segregation equation. Option D (53.00 cm) is designed to catch those who confuse the phase diagram composition ratio (0.53) with the actual solidified length.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4797, "question": "A specimen of a 4340 steel alloy with a plane strain fracture toughness of 54.8 MPa \\sqrt{m} (50 ksi \\sqrt{m}.) is exposed to a stress of 1030 MPa(150,000 psi). Will this specimen experience fracture if the largest surface crack is 0.5mm ( 0.02 in.) long? Why or why not? Assume that the parameter Y has a value of 1.0 .", "answer": "the specimen will not experience fracture because it can tolerate a critical stress of 1380 \\text{ mpa} before fracture, which is greater than the applied stress of 1030 \\text{ mpa}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定试样是否会断裂。答案中给出了具体的计算结果（临界应力为1380 MPa），并基于计算结果进行了判断。 | 知识层次: 题目需要进行多步计算，包括应用断裂力学公式计算临界应力，并与实际应力进行比较。虽然公式直接给出，但需要理解参数的含义并进行数值计算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及平面应变断裂韧性和临界应力的计算，需要应用公式进行多步骤计算，并综合分析计算结果与给定应力条件的关系。虽然题目提供了所有必要参数，但解题过程需要一定的材料力学知识和对断裂力学概念的理解。", "convertible": true, "correct_option": "the specimen will not experience fracture because it can tolerate a critical stress of 1380 mpa before fracture, which is greater than the applied stress of 1030 mpa.", "choice_question": "A specimen of a 4340 steel alloy with a plane strain fracture toughness of 54.8 MPa √m (50 ksi √m.) is exposed to a stress of 1030 MPa(150,000 psi). Will this specimen experience fracture if the largest surface crack is 0.5mm ( 0.02 in.) long? Assume that the parameter Y has a value of 1.0.", "conversion_reason": "The question can be converted into a multiple-choice format because it has a definitive answer that can be presented as one of the options. The original question is already in a form that can be directly used as a multiple-choice question stem, and the provided answer can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because the critical stress intensity factor (1380 MPa) exceeds the applied stress", "B": "Yes, because the crack length exceeds the critical flaw size for this stress level", "C": "No, because the alloy's yield strength (1450 MPa) prevents crack propagation", "D": "Yes, because the stress intensity factor (40.9 MPa√m) exceeds the fracture toughness" }, "correct_answer": "A", "explanation": "The correct answer is A because calculation shows σ_c = K_IC/(Y√(πa)) = 1380 MPa > 1030 MPa. B is wrong by misapplying critical flaw size concept. C uses correct yield strength data but irrelevant to fracture mechanics. D miscalculates the stress intensity factor (should be 40.9 MPa√m < 54.8 MPa√m).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1040, "question": "Please indicate the method of adding nucleating agents to refine the grain size of metal materials and its principle.", "answer": "Adding nucleating agents. Before the melt solidifies, some fine nucleating agents are added and dispersed in the melt to serve as ready-made substrates required for heterogeneous nucleation, thereby significantly increasing the number of nuclei and markedly refining the grain size.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释添加成核剂的方法及其原理，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查的是关于晶粒细化方法的基本概念和原理，主要涉及记忆和理解添加成核剂的作用及其原理，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生不仅记住添加成核剂的方法，还要理解其原理（即通过提供异质成核的基底来增加晶核数量从而细化晶粒）。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。因此，该题目在选择题型中属于等级2难度。", "convertible": true, "correct_option": "Adding nucleating agents. Before the melt solidifies, some fine nucleating agents are added and dispersed in the melt to serve as ready-made substrates required for heterogeneous nucleation, thereby significantly increasing the number of nuclei and markedly refining the grain size.", "choice_question": "Which of the following methods is used to refine the grain size of metal materials by adding nucleating agents and its principle?", "conversion_reason": "The answer is a standard explanation of a method and its principle, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Adding nucleating agents to provide heterogeneous nucleation sites", "B": "Applying rapid quenching to suppress nucleation entirely", "C": "Introducing dislocations to promote recrystallization", "D": "Using electromagnetic stirring to break dendrite arms" }, "correct_answer": "A", "explanation": "Correct answer is A because nucleating agents provide ready-made substrates for heterogeneous nucleation, increasing nuclei count and refining grains. B is wrong as quenching affects growth rate not nucleation. C is incorrect because dislocations influence recrystallization not initial solidification. D is a real process but affects dendrite morphology not grain refinement during nucleation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3583, "question": "Calculate the fraction of bonding of MgO that is ionic.", "answer": "the fraction of bonding of mgo that is ionic is 0.734. so bonding is mostly ionic.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算MgO的离子键比例），答案给出了具体的计算结果（0.734），属于典型的计算题特征。 | 知识层次: 题目涉及基本公式应用和简单计算，主要考查对离子键分数计算的理解和直接套用，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用基本公式进行单一计算，无需多个公式组合或复杂分析。学生只需掌握简单的离子键分数计算公式即可得出答案，属于最基础的难度等级。", "convertible": true, "correct_option": "0.734", "choice_question": "The fraction of bonding of MgO that is ionic is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.734", "B": "0.842", "C": "0.612", "D": "0.923" }, "correct_answer": "A", "explanation": "The correct answer is 0.734, calculated using the electronegativity difference between Mg and O. Option B (0.842) is designed to exploit the common misconception that ionic character increases linearly with electronegativity difference. Option C (0.612) targets the error of underestimating the ionic character due to Mg's relatively low electronegativity. Option D (0.923) is a trap for those who overestimate ionic character by ignoring covalent contributions in oxide ceramics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2503, "question": "What are the performance characteristics of diamond?", "answer": "Diamond has high hardness and a dense structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释钻石的性能特征，答案需要文字描述和论述，没有提供选项或要求计算 | 知识层次: 题目考查对钻石性能特征的基本概念记忆和理解，属于基础概念层次。 | 难度: 该题目属于基础概念记忆层次，仅需要考生回忆钻石的基本性能特征（高硬度和致密结构）。在选择题型中，这属于最简单的直接回忆类题目，不需要任何解释、分析或推理过程，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Diamond has high hardness and a dense structure.", "choice_question": "Which of the following describes the performance characteristics of diamond?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diamond has high hardness and a dense structure", "B": "Diamond exhibits high ductility and low thermal conductivity", "C": "Diamond shows anisotropic electrical conductivity similar to graphite", "D": "Diamond possesses metallic bonding characteristics" }, "correct_answer": "A", "explanation": "The correct answer is A because diamond's exceptional hardness stems from its covalent bonding and dense tetrahedral structure. Option B is incorrect as diamond has extremely low ductility (being brittle) and the highest known thermal conductivity. Option C exploits the carbon allotrope confusion - while graphite shows anisotropic conductivity, diamond is an electrical insulator. Option D creates a bonding misconception trap - diamond has purely covalent bonding, not metallic.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3479, "question": "What is the difference between the wear resistance principle of wear-resistant steel and that of quenched tool steel?", "answer": "The wear resistance principle of wear-resistant steel is that the single austenite structure is subjected to strong impact and pressure during work, resulting in stress-induced martensite and work hardening, which greatly increases the wear resistance of the steel. Quenched tool steel obtains high hardness and high wear resistance tempered martensite through quenching + low-temperature tempering, giving the steel high wear resistance.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释两种钢材的耐磨原理差异，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释两种钢材的耐磨原理，涉及材料微观结构转变（如奥氏体向马氏体的应力诱导转变）和热处理工艺（淬火+低温回火）对性能的影响。这需要综合运用材料科学知识，理解不同机制如何导致耐磨性提升，并进行对比分析，属于机理层面的解释和推理分析。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The wear resistance principle of wear-resistant steel is that the single austenite structure is subjected to strong impact and pressure during work, resulting in stress-induced martensite and work hardening, which greatly increases the wear resistance of the steel. Quenched tool steel obtains high hardness and high wear resistance tempered martensite through quenching + low-temperature tempering, giving the steel high wear resistance.", "choice_question": "What is the difference between the wear resistance principle of wear-resistant steel and that of quenched tool steel?", "conversion_reason": "The answer is a standard explanation that can be used as a correct option in a multiple-choice question. The question can be reformatted to fit a multiple-choice format by providing the correct answer as one of the options and creating plausible distractors for the other choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Wear-resistant steel relies on strain-induced martensitic transformation during service, while tool steel achieves wear resistance through pre-formed tempered martensite", "B": "Both steels utilize carbide precipitation hardening, but tool steel has finer carbides due to lower tempering temperatures", "C": "Wear-resistant steel forms a protective oxide layer during friction, while tool steel maintains wear resistance through retained austenite", "D": "The key difference lies in their elastic modulus - tool steel has higher stiffness which prevents abrasive particle penetration" }, "correct_answer": "A", "explanation": "Option A correctly identifies the fundamental difference: wear-resistant steel's in-service transformation versus tool steel's pre-formed structure. Option B is misleading as it overemphasizes carbide size while ignoring the primary mechanisms. Option C incorrectly attributes oxide layer formation to wear-resistant steel. Option D introduces an irrelevant material property (elastic modulus) that doesn't directly govern wear resistance in these cases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 446, "question": "What is the total cost for carburizing 500 gears at 1000°C (1273K) for 3.299 hours, given the cost is 1500 yuan per hour?", "answer": "Total cost = 1500 yuan/h * 3.299 h = 4948.5 yuan", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算总成本），并给出了具体的计算公式和步骤，符合计算题的特征。 | 知识层次: 题目仅涉及基本公式应用和简单计算，无需多步推理或综合分析，仅需将给定数值直接套用乘法公式即可得出结果。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行简单计算（总成本=每小时成本×时间），无需额外的概念理解或复杂步骤，属于最基础的难度等级。", "convertible": true, "correct_option": "4948.5 yuan", "choice_question": "What is the total cost for carburizing 500 gears at 1000°C (1273K) for 3.299 hours, given the cost is 1500 yuan per hour?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4948.5 yuan", "B": "1500 yuan", "C": "3299 yuan", "D": "1273 yuan" }, "correct_answer": "A", "explanation": "The correct answer is A (4948.5 yuan) calculated by multiplying the hourly cost (1500 yuan) by the duration (3.299 hours). Option B (1500 yuan) exploits the cognitive bias of using only the hourly rate without considering duration. Option C (3299 yuan) is a numerical trap using the hours figure (3.299) incorrectly scaled up. Option D (1273 yuan) uses the temperature value (1273K) as a distraction from the actual calculation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2324, "question": "Why are most covalent solids low-density materials?", "answer": "Most covalent solids have low packing density because the interatomic bonds are constrained by bond saturation and directionality.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么大多数共价固体是低密度材料，答案提供了文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求解释共价固体低密度的原因，涉及共价键的方向性和饱和性等复杂概念，需要综合运用材料科学知识进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它要求考生不仅理解共价固体的基本性质，还需要深入分析键饱和性和方向性对堆积密度的影响机制。正确选项涉及对共价键特性的机理解释，需要综合运用材料科学知识进行推理分析，这超出了简单记忆或基础理解的范畴。在选择题型内，这类需要机理深度解释的题目通常属于难度等级4。", "convertible": true, "correct_option": "Most covalent solids have low packing density because the interatomic bonds are constrained by bond saturation and directionality.", "choice_question": "Why are most covalent solids low-density materials?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The directional nature of covalent bonds prevents efficient atomic packing", "B": "Covalent solids have weaker interatomic forces compared to metallic bonds", "C": "The electron cloud repulsion in covalent solids creates larger interatomic distances", "D": "Covalent solids typically form at lower temperatures where atomic vibrations reduce packing efficiency" }, "correct_answer": "A", "explanation": "Correct answer A highlights the key structural constraint of directional covalent bonds. Distractors: B exploits confusion between bond strength and packing efficiency (covalent bonds are actually stronger than metallic); C misapplies metallic bonding concepts to covalent solids; D creates a false temperature correlation that seems plausible but isn't the fundamental reason.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3461, "question": "How is tool steel further classified?", "answer": "Tool steel is divided into: cutting tool steel, die steel, and measuring tool steel. Cutting tool steel is divided into: carbon tool steel, low-alloy tool steel, and high-speed steel. Die steel is divided into: cold work die steel and hot work die steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对工具钢的分类进行详细解释和论述，答案提供了详细的分类和子分类，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对工具钢分类的基本概念记忆和理解，不需要复杂的分析或应用，仅需回忆和列举工具钢的分类及其子类。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个分类层次（工具钢的三大类及其子类），但主要考察的是基础概念的记忆和分类体系的掌握。不需要复杂的分析或推理过程，只需准确回忆工具钢的分类体系即可。相比等级1的简单定义题，该题需要记忆更多分类细节；但相比等级3需要阐述复杂概念体系的题目，该题仍属于概念解释和描述层面的难度。", "convertible": true, "correct_option": "Tool steel is divided into: cutting tool steel, die steel, and measuring tool steel. Cutting tool steel is divided into: carbon tool steel, low-alloy tool steel, and high-speed steel. Die steel is divided into: cold work die steel and hot work die steel.", "choice_question": "How is tool steel further classified?", "conversion_reason": "The answer is a standard classification of tool steel, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "By application: cutting tools, dies, and measuring instruments", "B": "By carbon content: low-carbon, medium-carbon, and high-carbon tool steel", "C": "By heat treatment method: annealed, quenched, and tempered tool steel", "D": "By alloying elements: tungsten, molybdenum, and vanadium-based tool steels" }, "correct_answer": "A", "explanation": "The correct classification is by application (A), which divides tool steel into cutting tools, dies, and measuring instruments. Option B exploits the cognitive bias of associating classification with carbon content, which is common for other steels but not the primary classification for tool steel. Option C uses heat treatment methods that apply to all steels but don't represent classification criteria. Option D lists common alloying elements but incorrectly presents them as classification categories, exploiting the professional's tendency to focus on composition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3938, "question": "The concentration of carbon in an iron-carbon alloy is 0.57 wt%. What is the concentration in kilograms of carbon per cubic meter of alloy? The densities of iron and carbon are 7.87 and 2.25 \\mathrm{g} / {cm}^{3}, respectively.", "answer": "the concentration of carbon is 11.8 kg / m^{3}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及浓度转换和密度计算，最终需要得出具体的数值结果（11.8 kg/m³）。答案形式为计算得出的具体数值，而非选择、判断或文字解释。 | 知识层次: 题目需要进行多步计算，涉及质量分数转换、密度计算和单位换算，需要综合运用多个概念和公式，但不需要复杂的推理或创新思维。 | 难度: 在选择题中属于中等偏上难度，需要理解质量分数与体积浓度的转换，涉及密度计算和单位换算，属于综合性计算问题。虽然题目给出了关键数据，但解题过程需要多步骤计算和概念关联，对学生的应用能力有一定要求。", "convertible": true, "correct_option": "11.8 kg / m^{3}", "choice_question": "The concentration of carbon in an iron-carbon alloy is 0.57 wt%. What is the concentration in kilograms of carbon per cubic meter of alloy, given the densities of iron and carbon are 7.87 and 2.25 g/cm³, respectively?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "11.8 kg/m³", "B": "5.7 kg/m³", "C": "22.4 kg/m³", "D": "8.9 kg/m³" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算得出的：首先计算合金密度（假设100g合金，含0.57g碳和99.43g铁，总体积=99.43/7.87 + 0.57/2.25 ≈ 12.73 cm³），然后碳浓度=0.57g/(12.73cm³)=0.0448 g/cm³=44.8 kg/m³，再乘以重量分数0.57%得到11.8 kg/m³。干扰项B是直接错误地将重量百分比转换为kg/m³（0.57→5.7），利用了单位转换的直觉陷阱。干扰项C错误地假设碳以石墨形式存在（密度2.25g/cm³）并占据全部体积。干扰项D是铁和碳密度的简单平均值（(7.87+2.25)/2≈5.06 g/cm³）的错误转换，利用了材料混合的直觉误区。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2602, "question": "Estimate the equilibrium width of an extended dislocation in Cu. Given: lattice constant of Cu a = 0.361 nm, shear modulus G = 5×10^6 N/cm^2, stacking fault energy γ_I = 45×10^-6 J/m^2.", "answer": "Cu has a face-centered cubic structure, and the equilibrium width of an extended dislocation d_0 = G a^2 / (24πγ_I). Substituting the data: d_0 = (5×10^6 N/cm^2) × (0.361×10^-9 m)^2 / (24π × 45×10^-6 J/m^2) = 1.92×10^-6 m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和数据进行数值计算，最终得出一个具体的数值结果（1.92×10^-6 m）。解答过程涉及公式应用和单位转换，符合计算题的特征。 | 知识层次: 题目主要考查基本公式的直接应用和简单计算，涉及到的知识点较为基础，思维过程较为直接，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要理解扩展位错的概念和基本公式，但解题步骤相对直接，只需将给定数据代入单一公式进行计算即可。不需要多个公式组合或复杂推导，符合等级2的标准。", "convertible": true, "correct_option": "1.92×10^-6 m", "choice_question": "Estimate the equilibrium width of an extended dislocation in Cu. Given: lattice constant of Cu a = 0.361 nm, shear modulus G = 5×10^6 N/cm^2, stacking fault energy γ_I = 45×10^-6 J/m^2.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.92×10^-6 m", "B": "3.84×10^-6 m", "C": "9.61×10^-7 m", "D": "4.80×10^-7 m" }, "correct_answer": "A", "explanation": "正确答案A基于Peierls-Nabarro模型计算：w = G*b^2/(8π^2*γ_I)，其中b = a/√2。干扰项B是忘记除以2π的结果，C是错误使用弹性模量而非剪切模量计算，D是单位换算错误导致的陷阱。这些干扰项利用了材料参数混淆和计算步骤遗漏等常见AI错误模式。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 434, "question": "7.Typical ingot structure usually has (19)", "answer": "Central equiaxed crystal zone", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（Central equiaxed crystal zone）作为答案，这属于需要简短文字回答的问题类型，而不是从多个选项中选择或判断对错 | 知识层次: 题目考查典型铸锭结构的基本概念记忆，属于定义和分类等记忆性知识。 | 难度: 在选择题型中，该题目仅考察对典型铸锭结构的基本定义记忆，属于最基础的概念性知识。学生只需识别\"Central equiaxed crystal zone\"这一标准术语即可作答，无需进行概念解释或复杂分析，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Central equiaxed crystal zone", "choice_question": "Typical ingot structure usually has:", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Central equiaxed crystal zone", "B": "Peripheral columnar crystal zone", "C": "Uniform dendritic structure throughout", "D": "Amorphous surface layer" }, "correct_answer": "A", "explanation": "The central equiaxed crystal zone is the correct answer as it is a characteristic feature of typical ingot structures due to slower cooling rates at the center. Option B exploits the common intuition that columnar structures dominate, but these actually form at the periphery. Option C creates a false expectation of uniformity, while Option D plays on the misconception that rapid surface cooling always leads to amorphous phases in ingots.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 353, "question": "What is the main structural difference between (metal-based) solid solutions and intermediate phases?", "answer": "Solid solutions retain the crystal structure of the pure metal, while the structure of intermediate phases is generally different from that of both constituent elements.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释金属基固溶体和中间相的主要结构差异，答案需要文字解释和论述，没有提供选项或要求判断对错或进行数值计算。 | 知识层次: 题目考查对固溶体和中间相的基本概念和结构差异的记忆和理解，属于基础概念层次的知识点。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并区分两种不同的结构类型（固溶体和中间相），并记住它们的关键区别特征。这比单纯记忆单一概念的定义（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Solid solutions retain the crystal structure of the pure metal, while the structure of intermediate phases is generally different from that of both constituent elements.", "choice_question": "What is the main structural difference between (metal-based) solid solutions and intermediate phases?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solutions maintain the host metal's crystal structure while intermediate phases form new structures", "B": "Solid solutions always have higher symmetry than intermediate phases", "C": "Intermediate phases exhibit complete solubility while solid solutions have limited solubility", "D": "The main difference lies in their electrical conductivity rather than crystal structure" }, "correct_answer": "A", "explanation": "Correct answer A precisely captures the fundamental structural distinction. Option B exploits symmetry misconceptions - while often true, symmetry isn't the defining difference. Option C reverses the solubility characteristic, a common confusion. Option D introduces an irrelevant property (conductivity) that may mislead models focusing on material properties rather than structural fundamentals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 392, "question": "In a binary system, the transformation that occurs at a certain temperature, L1 = L2 + α, is called (15) transformation.", "answer": "(15) monotectic transformation", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（monotectic transformation）来完成句子，而不是从多个选项中选择、判断对错或进行数值计算。这种形式更接近于简答题，需要学生对材料科学中的相变类型有准确的理解和记忆。 | 知识层次: 题目考查对二元系统中特定相变类型（monotectic transformation）的基本概念记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，此题属于基础概念记忆题，仅需考生回忆二元系统中特定温度下发生的相变类型名称（monotectic transformation）。题目直接给出定义式(L1 = L2 + α)，只需匹配术语，无需解释或分析过程，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "monotectic transformation", "choice_question": "In a binary system, the transformation that occurs at a certain temperature, L1 = L2 + α, is called:", "conversion_reason": "The answer is a standard term (monotectic transformation), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "monotectic transformation", "B": "eutectic transformation", "C": "peritectic transformation", "D": "spinodal decomposition" }, "correct_answer": "A", "explanation": "The correct answer is A because the equation L1 = L2 + α describes a monotectic reaction where a liquid (L1) decomposes into another liquid (L2) and a solid phase (α). Option B is a common confusion as eutectic transformations are more frequently encountered, but involve L = α + β. Option C is a plausible distraction as peritectic reactions also involve liquid phases, but follow the pattern L + α = β. Option D exploits the tendency to associate phase separation with spinodal decomposition, even though it's an entirely different mechanism not involving liquid phases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3072, "question": "What is hot pressing sintering?", "answer": "Hot pressing sintering is a method that uses ceramic powders of various compounds as raw materials, adds a small amount of additives, loads them into graphite molds, and sinters and forms under high temperature and high pressure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对“hot pressing sintering”进行解释和论述，答案提供了详细的文字描述，符合简答题的特征。 | 知识层次: 题目考查热压烧结的基本定义和过程，属于基础概念的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆热压烧结的基本定义和过程，包括原材料、添加剂、模具类型以及烧结条件等关键要素。虽然涉及多个知识点，但都属于基础概念记忆范畴，不需要进行复杂的概念体系阐述或比较分析。因此，在选择题型内属于中等难度。", "convertible": true, "correct_option": "Hot pressing sintering is a method that uses ceramic powders of various compounds as raw materials, adds a small amount of additives, loads them into graphite molds, and sinters and forms under high temperature and high pressure.", "choice_question": "Which of the following best describes hot pressing sintering?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as the correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hot pressing sintering is a method that uses ceramic powders of various compounds as raw materials, adds a small amount of additives, loads them into graphite molds, and sinters and forms under high temperature and high pressure.", "B": "Hot pressing sintering involves melting metal powders in a vacuum chamber and then pressing them into shape under controlled cooling rates.", "C": "Hot pressing sintering is a room-temperature process where ceramic powders are compressed under ultra-high pressure without any heating.", "D": "Hot pressing sintering refers to the laser-assisted sintering of polymer composites where localized heating and pressure are applied simultaneously." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the key aspects of hot pressing sintering: ceramic powders, additives, graphite molds, and simultaneous application of heat and pressure. Option B incorrectly describes a metal melting process. Option C describes cold pressing, not hot pressing. Option D describes a polymer processing technique unrelated to ceramic sintering. Advanced AIs might be misled by option B due to its plausible-sounding description of a high-temperature process, or option D due to its mention of simultaneous heat/pressure application which partially matches the correct concept.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1745, "question": "a≠b≠c,α≠β≠γ crystals belong to the crystal system. a. cubic b. hexagonal c. tetragonal d. orthorhombic", "answer": "d", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从四个选项（a. cubic b. hexagonal c. tetragonal d. orthorhombic）中选择正确答案，符合选择题的特征 | 知识层次: 题目考查晶体系统分类的基本概念记忆，只需记住不同晶体系统的晶格参数特征即可选择正确答案。 | 难度: 在选择题中属于中等偏下难度，需要理解晶体系统的基本分类和特征，并能根据题目描述的条件（a≠b≠c,α≠β≠γ）进行简单辨析，但不需要复杂的分析或深度理解多个概念。", "convertible": true, "correct_option": "d", "choice_question": "a≠b≠c,α≠β≠γ crystals belong to the crystal system.", "conversion_reason": "原题目已经是单选题格式，只需提取正确选项和保持题目原样。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship predicts increased yield strength with decreasing grain size due to dislocation pile-up at grain boundaries", "B": "The Hall-Petch relationship shows decreased yield strength with finer grain size because of increased grain boundary sliding", "C": "The Hall-Petch relationship becomes invalid below a critical grain size where grain boundary diffusion dominates", "D": "The Hall-Petch relationship demonstrates linear proportionality between yield strength and the square root of grain size" }, "correct_answer": "D", "explanation": "The correct answer is D because the Hall-Petch relationship mathematically expresses yield strength as linearly proportional to the inverse square root of grain size. Option A uses correct physical mechanism (dislocation pile-up) but incorrectly describes the mathematical relationship. Option B reverses the actual trend, exploiting common misconceptions about grain boundary effects. Option C describes a real phenomenon (breakdown of Hall-Petch at nanoscale) but falsely presents it as part of the original relationship, creating a subtle context-switching trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1918, "question": "In the non-stoichiometric compound FexO, Fe3+/Fe2+=0.1. Find the vacancy concentration in the non-stoichiometric compound FexO.", "answer": "According to the reaction formula Fe_xO → Fe2O3 → Fe0 → 2Fe_Fe^· + V_Fe^′′ + 3O_∘; Fe_1-3y^2+ Fe_2y^3+ O, let y be the mole fraction of Fe3+, then 2y/(1-3y) = 0.1. Solving gives y = 1/23 ≈ 0.043. The vacancy concentration is y/(1 + x), where x = 1 - y = 0.957, thus the vacancy concentration is 0.043 / (1 + 0.957) ≈ 2.2%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解非化学计量化合物FexO中的空位浓度，答案给出了具体的计算过程和结果。 | 知识层次: 题目涉及非化学计量化合物FexO中Fe3+/Fe2+比值的计算，需要通过反应公式建立方程并求解，涉及多步计算和概念关联。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力和对非化学计量化合物缺陷化学的理解。 | 难度: 在选择题中属于中等偏上难度，需要理解非化学计量化合物的概念，建立反应方程式，并进行多步计算。虽然题目提供了部分解题步骤，但仍需要综合分析Fe3+/Fe2+比例与空位浓度之间的关系，并进行代数求解。这比简单的概念选择题或单步计算题更复杂，但尚未达到涉及多变量或高度抽象思维的复杂计算问题水平。", "convertible": true, "correct_option": "2.2%", "choice_question": "In the non-stoichiometric compound FexO, Fe3+/Fe2+=0.1. What is the vacancy concentration in the non-stoichiometric compound FexO?", "conversion_reason": "The answer to the calculation is a specific numerical value (2.2%), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.2%", "B": "4.8%", "C": "1.1%", "D": "9.1%" }, "correct_answer": "A", "explanation": "The correct answer is 2.2% because the Fe3+/Fe2+ ratio of 0.1 leads to a specific vacancy concentration calculation in the non-stoichiometric FexO compound. Option B (4.8%) is a cognitive bias trap that might arise from incorrectly doubling the correct value. Option C (1.1%) exploits the common mistake of halving the correct answer due to misinterpreting the ratio. Option D (9.1%) is designed to catch those who might invert the Fe3+/Fe2+ ratio calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 998, "question": "Please analyze the characteristics and mechanisms of work hardening.", "answer": "Work hardening: is the strengthening caused by the multiplication of dislocations due to plastic deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析work hardening的特性和机制，需要文字解释和论述，答案也提供了简要的解释，符合简答题的特征。 | 知识层次: 题目要求分析加工硬化的特征和机制，涉及对位错增殖和塑性变形等复杂机理的解释和综合分析，需要深入理解和推理分析能力。 | 难度: 在选择题型中，该题目属于较高难度。题目要求分析加工硬化的特性和机理，正确选项涉及位错增殖和塑性变形的综合理解。这需要考生不仅掌握位错理论的基本概念，还要能够将这些概念与材料强化机制联系起来进行机理层面的解释。在选择题型内，这种需要综合运用知识并理解深层机理的题目属于等级4难度。", "convertible": true, "correct_option": "Work hardening: is the strengthening caused by the multiplication of dislocations due to plastic deformation.", "choice_question": "Which of the following best describes the characteristics and mechanisms of work hardening?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice format by presenting it as the correct option among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Work hardening is the strengthening caused by the multiplication of dislocations due to plastic deformation.", "B": "Work hardening occurs when elastic deformation leads to atomic bond stretching, increasing the material's resistance to further deformation.", "C": "Work hardening results from the reduction of grain boundaries during plastic deformation, which decreases dislocation mobility.", "D": "Work hardening is primarily caused by the formation of new crystalline phases during mechanical loading." }, "correct_answer": "A", "explanation": "The correct answer is A because work hardening fundamentally involves dislocation multiplication and entanglement during plastic deformation. Option B incorrectly associates work hardening with elastic deformation. Option C misattributes the mechanism to grain boundary reduction rather than dislocation interactions. Option D introduces an erroneous phase transformation concept that doesn't apply to work hardening. These distractors exploit common misconceptions about deformation mechanisms and phase changes in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1015, "question": "For cold-rolled pure copper sheets, if high strength is required, what heat treatment should be performed?", "answer": "To maintain high strength, low-temperature annealing should be performed to allow only recovery and eliminate residual stresses.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释应该进行何种热处理以获得高强度，答案提供了文字解释和论述，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目要求考生理解冷轧纯铜板材的性能需求，并选择适当的热处理工艺。这需要将材料加工（冷轧）与热处理知识关联起来，分析不同热处理工艺（如低温退火）对材料性能（强度）的影响。虽然不涉及复杂计算，但需要多步概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解冷轧纯铜板材的强化机制（加工硬化）与热处理的关系，并能综合分析低温退火（仅发生回复过程）对残余应力和强度的具体影响。题目要求将材料加工工艺与微观结构变化相关联，但选项本身提供了明确的方向指引，降低了纯粹记忆性知识的难度。", "convertible": true, "correct_option": "Low-temperature annealing to allow only recovery and eliminate residual stresses", "choice_question": "For cold-rolled pure copper sheets, if high strength is required, which heat treatment should be performed?", "conversion_reason": "The answer is a standard and specific heat treatment process, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Low-temperature annealing (200-300°C) for 1 hour", "B": "Solution treatment at 800°C followed by water quenching", "C": "High-temperature recrystallization annealing (600-700°C)", "D": "Stress relief annealing at 400°C for 2 hours" }, "correct_answer": "A", "explanation": "The correct answer is A because cold-rolled pure copper achieves maximum strength through recovery without recrystallization. Low-temperature annealing eliminates residual stresses while preserving dislocation structures from cold working. B is incorrect as solution treatment would erase all cold work effects. C is a trap as recrystallization would reduce strength by forming new dislocation-free grains. D is a subtle trap - while it relieves stress, 400°C may initiate partial recrystallization in some copper alloys.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4597, "question": "Briefly explain why metals are typically better thermal conductors than ceramic materials.", "answer": "Metals are typically better thermal conductors than are ceramic materials because, for metals, most of the heat is transported by free electrons (of which there are relatively large numbers). In ceramic materials, the primary mode of thermal conduction is via phonons, and phonons are more easily scattered than are free electrons.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释金属比陶瓷材料导热性更好的原因，答案通过文字解释和论述来回答，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释金属和陶瓷材料在热传导性能上的差异，涉及自由电子和声子两种不同的热传导机制，以及它们被散射的难易程度。这需要对材料的热传导机理有深入的理解和分析能力，属于对复杂概念的关联和解释。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅理解金属和陶瓷材料的热传导机制差异，还需要掌握自由电子和声子在热传导中的作用原理。正确选项涉及对两种不同传导机制（电子传导 vs 声子传导）的比较分析，并需要理解散射效应对传导效率的影响。这种题目超越了简单的事实记忆，要求考生能够综合运用材料科学知识进行机理层面的解释，符合等级4\"机理深度解释\"的标准。", "convertible": true, "correct_option": "Metals are typically better thermal conductors than are ceramic materials because, for metals, most of the heat is transported by free electrons (of which there are relatively large numbers). In ceramic materials, the primary mode of thermal conduction is via phonons, and phonons are more easily scattered than are free electrons.", "choice_question": "Why are metals typically better thermal conductors than ceramic materials?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metals have higher atomic packing factors which allow more efficient phonon transport", "B": "Ceramic materials have stronger covalent bonds that impede electron movement", "C": "The crystalline defects in ceramics create more scattering centers than in metals", "D": "Metals contain free electrons that can transport heat more efficiently than phonons in ceramics" }, "correct_answer": "D", "explanation": "The correct answer is D because metals have free electrons that dominate thermal conduction, while ceramics rely on less efficient phonon transport. Option A is incorrect because atomic packing affects phonon transport, but metals' thermal conductivity is primarily due to electrons. Option B exploits a common misconception about bond strength, but covalent bonds in ceramics actually enhance phonon transport. Option C contains a partial truth (defects do scatter phonons), but this is secondary to the fundamental electron vs phonon conduction difference.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2901, "question": "Briefly describe the methods of polymer alloying", "answer": "The preparation methods of polymer alloys can be divided into physical methods and chemical methods. Physical blending methods include dry powder blending, melt blending, and latex blending, with melt blending being the most commonly used. Chemical blending methods mainly include copolymerization-blending and interpenetrating polymer network methods.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述聚合物合金化的方法，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对聚合物合金制备方法的基本分类和简单描述，主要涉及记忆性知识，如物理方法和化学方法的具体类型及其特点，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求描述聚合物合金化的方法，但正确选项已经提供了明确的分类和具体方法，包括物理方法和化学方法的具体类型。这需要考生不仅记住基本概念，还要理解并区分不同的制备方法。然而，由于选项已经结构化地呈现了信息，不需要考生自行组织复杂的概念体系，因此难度属于等级2。", "convertible": true, "correct_option": "The preparation methods of polymer alloys can be divided into physical methods and chemical methods. Physical blending methods include dry powder blending, melt blending, and latex blending, with melt blending being the most commonly used. Chemical blending methods mainly include copolymerization-blending and interpenetrating polymer network methods.", "choice_question": "Which of the following accurately describes the methods of polymer alloying?", "conversion_reason": "The answer is a standard description of polymer alloying methods, which can be converted into a multiple-choice question format by presenting the correct description among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polymer alloying methods are strictly limited to physical blending techniques like melt mixing and solution casting", "B": "Chemical copolymerization is the only effective method for creating polymer alloys with stable phase structures", "C": "The preparation methods of polymer alloys can be divided into physical methods and chemical methods, with melt blending being the most common physical method", "D": "Interpenetrating polymer networks are considered a physical blending method due to their mechanical entanglement nature" }, "correct_answer": "C", "explanation": "The correct answer C accurately describes the dual classification of polymer alloying methods into physical and chemical categories, specifically noting melt blending as the most common physical method. Option A incorrectly limits methods to only physical blending. Option B overstates the exclusivity of chemical methods. Option D misclassifies interpenetrating networks which are actually chemical methods despite their entanglement characteristics. These distractors exploit common misconceptions about method exclusivity (A/B) and classification criteria (D).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3256, "question": "Describe the recovery mechanism at low temperatures of 0.1~0.3Tm", "answer": "Recovery at 0.1~0.3Tm low temperatures primarily involves the movement of point defects, where vacancies and interstitial atoms migrate to grain boundaries or dislocations and annihilate, the recombination of vacancies and interstitial atoms, and the aggregation of vacancies to form vacancy pairs or vacancy clusters, leading to a significant reduction in point defect density.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求描述低温下的恢复机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释低温下的回复机制，涉及点缺陷的迁移、湮灭和聚集等微观过程，需要综合运用材料科学中的缺陷理论和热力学知识，进行机理层面的分析和解释。这超出了简单记忆或基本应用的范畴，属于需要深入理解和综合分析的内容。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求对低温恢复机制进行全面的机理解释，涉及点缺陷（空位和间隙原子）的迁移、复合以及聚集形成空位对或空位团簇等复杂现象的综合分析。这不仅需要深入理解材料科学中的缺陷理论，还需要能够将这些概念综合运用来解释具体的恢复过程。此外，题目还要求对温度范围（0.1~0.3Tm）的影响有清晰的认识，进一步增加了题目的复杂性和难度。因此，在选择题型中，该题目属于复杂现象全面分析的难度等级。", "convertible": true, "correct_option": "Recovery at 0.1~0.3Tm low temperatures primarily involves the movement of point defects, where vacancies and interstitial atoms migrate to grain boundaries or dislocations and annihilate, the recombination of vacancies and interstitial atoms, and the aggregation of vacancies to form vacancy pairs or vacancy clusters, leading to a significant reduction in point defect density.", "choice_question": "Which of the following best describes the recovery mechanism at low temperatures of 0.1~0.3Tm?", "conversion_reason": "The answer is a standard description of a scientific concept, which can be converted into a multiple-choice question by presenting it as the correct option among plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recovery at 0.1~0.3Tm low temperatures primarily involves the movement of point defects, where vacancies and interstitial atoms migrate to grain boundaries or dislocations and annihilate, the recombination of vacancies and interstitial atoms, and the aggregation of vacancies to form vacancy pairs or vacancy clusters, leading to a significant reduction in point defect density.", "B": "Recovery at 0.1~0.3Tm is dominated by dislocation climb and cross-slip mechanisms, similar to high-temperature recovery processes but occurring at slower rates due to reduced thermal activation.", "C": "Low-temperature recovery (0.1~0.3Tm) mainly consists of stress relaxation through elastic strain recovery, with minimal contribution from defect migration or annihilation processes.", "D": "At 0.1~0.3Tm, recovery occurs through spontaneous recrystallization where new strain-free grains nucleate and grow to replace the deformed microstructure." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the point defect-dominated recovery mechanisms at low temperatures (0.1~0.3Tm). Option B is a cognitive bias trap - while describing real high-temperature mechanisms, it incorrectly applies them to low-T conditions. Option C exploits elastic deformation intuition but ignores the well-documented point defect mobility in this range. Option D uses recrystallization terminology which doesn't occur below ~0.4Tm, targeting AI's tendency to overgeneralize phase transformation concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4533, "question": "For a continuous and oriented fiber-reinforced composite, the modulus of elasticity in the transverse direction is 3.66 GPa (5.3 x 10^5 psi). If the volume fraction of fibers is 0.25, determine the modulus of elasticity of the matrix phase.", "answer": "the modulus of elasticity of the matrix phase e_m is 2.79 GPa (4.04 x 10^5 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的参数（纤维体积分数和横向弹性模量）应用公式计算基体相的弹性模量，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用复合材料横向弹性模量的计算公式，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等难度，需要理解复合材料横向弹性模量的计算公式，并能够正确代入已知条件进行多步计算。题目涉及体积分数和弹性模量的关系，需要综合分析能力。虽然计算过程不算极其复杂，但需要准确掌握相关概念和公式。", "convertible": true, "correct_option": "2.79 GPa (4.04 x 10^5 psi)", "choice_question": "For a continuous and oriented fiber-reinforced composite, the modulus of elasticity in the transverse direction is 3.66 GPa (5.3 x 10^5 psi). If the volume fraction of fibers is 0.25, what is the modulus of elasticity of the matrix phase?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.79 GPa (4.04 x 10^5 psi)", "B": "3.66 GPa (5.3 x 10^5 psi)", "C": "4.88 GPa (7.08 x 10^5 psi)", "D": "1.83 GPa (2.65 x 10^5 psi)" }, "correct_answer": "A", "explanation": "The correct answer uses the inverse rule of mixtures for transverse modulus calculation: 1/E_transverse = V_f/E_f + V_m/E_m. Option B is a direct copy of the given transverse modulus, exploiting the tendency to confuse composite properties with matrix properties. Option C reverses the volume fractions in the calculation, a common error when hastily applying mixture rules. Option D uses a simple linear interpolation between fiber and matrix moduli, which is incorrect for transverse loading but appeals to intuitive estimation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4825, "question": "For the following pair of polymers, do the following: (1) state whether it is possible to determine whether one polymer has a higher melting temperature than the other; (2) if it is possible, note which has the higher melting temperature and then cite reason(s) for your choice; and (3) if it is not possible to decide, then state why. Branched polyethylene having a number-average molecular weight of 850,000 g/mol; linear polyethylene having a number-average molecular weight of 850,000 g/mol", "answer": "Yes, it is possible to determine which polymer has the higher melting temperature. The linear polyethylene will most likely have a higher percent crystallinity, and, therefore, a higher melting temperature than the branched polyethylene. The molecular weights of both materials are the same and, thus, molecular weight is not a consideration.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对两种聚合物的熔点进行比较，并解释原因。答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目要求比较两种聚乙烯的熔点，并解释原因。这需要理解分子结构（线性和支化）对结晶度和熔点的影响，以及分子量的作用。虽然不涉及复杂计算，但需要综合分析多个因素（分子结构、结晶度、分子量）并做出判断，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求考生理解聚乙烯的分子结构（线性和支化）对结晶度和熔点的影响，还需要考生能够综合分析分子量相同的情况下，结构差异如何影响材料性能。此外，题目要求考生进行多步推理和比较，包括判断可能性、选择正确选项并解释原因，这涉及到多角度分析和论述。因此，该题目在选择题型内属于等级4的难度。", "convertible": true, "correct_option": "The linear polyethylene will most likely have a higher percent crystallinity, and, therefore, a higher melting temperature than the branched polyethylene.", "choice_question": "For the following pair of polymers, which one has a higher melting temperature and why? Branched polyethylene having a number-average molecular weight of 850,000 g/mol; linear polyethylene having a number-average molecular weight of 850,000 g/mol", "conversion_reason": "The original question asks for a comparison and reasoning, which can be effectively converted into a multiple-choice question by providing the correct reasoning as one of the options. The answer is a standard explanation that fits well within a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Linear polyethylene due to higher chain mobility allowing better crystal packing", "B": "Branched polyethylene because side chains increase molecular entanglement", "C": "Both have identical melting points since molecular weights are equal", "D": "Cannot be determined without knowing the degree of branching" }, "correct_answer": "A", "explanation": "The correct answer is A because linear chains can pack more efficiently into crystalline regions, increasing melting temperature. B is incorrect because while branching increases entanglement, it disrupts crystallinity. C is wrong because molecular weight alone doesn't determine melting point when chain architecture differs. D is a partial truth trap - while degree of branching matters, we can definitively say linear will have higher Tm than branched at same MW.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3390, "question": "What is the approximate tempering process in the process route of round dies made of 9SiCr steel?", "answer": "Tempering process: 160-180°C.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释9SiCr钢制圆模的回火工艺温度范围，答案给出了具体的温度区间（160-180°C），属于需要简要回答具体参数的简答题形式。 | 知识层次: 题目考查对9SiCr钢回火工艺温度范围的基础记忆，属于材料热处理工艺中的基本参数知识，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目仅要求记忆特定钢种（9SiCr）的特定热处理工艺参数（回火温度范围160-180°C），属于基础概念记忆层面的单一知识点考察。题目不涉及概念解释、工艺原理分析或复杂工艺路线比较，完全符合等级1\"基本定义简答\"的特征。选择题型中此类题目只需识别正确数值即可作答，对认知层次的要求最低。", "convertible": true, "correct_option": "160-180°C", "choice_question": "What is the approximate tempering process in the process route of round dies made of 9SiCr steel?", "conversion_reason": "The answer is a specific temperature range, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "160-180°C", "B": "200-220°C", "C": "250-270°C", "D": "300-320°C" }, "correct_answer": "A", "explanation": "The correct tempering temperature for 9SiCr steel round dies is 160-180°C to achieve optimal hardness-toughness balance. Option B (200-220°C) is a common mistake from confusing with general tool steel tempering ranges. Option C (250-270°C) exploits the cognitive bias of higher temperatures being 'safer'. Option D (300-320°C) is designed to trap those who mistake 9SiCr for high-speed steel tempering ranges.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3718, "question": "(a) A 3-in.-diameter rod of copper is to be reduced to a 2-in.-diameter rod by being pushed through an opening. To account for the elastic strain, what should be the diameter of the opening? The modulus of elasticity for the copper is 17 × 10^{6} psi and the yield strength is 40,000 psi.", "answer": "the diameter of the opening should be 1.995 in.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定开口的直径。答案是一个具体的数值结果（1.995 in.），这表明解答过程涉及计算步骤。 | 知识层次: 题目需要进行多步计算，涉及弹性应变和材料性能的综合分析，需要理解并应用弹性模量和屈服强度的概念，以及相关的计算公式。虽然不涉及复杂的推理或创新设计，但比简单的直接套用公式更复杂。 | 难度: 在选择题中属于中等偏上难度，需要理解弹性应变、模量、屈服强度等概念，并进行多步计算和综合分析。题目要求考生能够将理论知识与实际应用相结合，通过计算确定合适的开口直径。虽然给出了正确选项，但解题过程涉及多个步骤和概念的综合运用，对考生的理解能力和计算能力有一定要求。", "convertible": true, "correct_option": "1.995 in.", "choice_question": "A 3-in.-diameter rod of copper is to be reduced to a 2-in.-diameter rod by being pushed through an opening. To account for the elastic strain, what should be the diameter of the opening? The modulus of elasticity for the copper is 17 × 10^{6} psi and the yield strength is 40,000 psi.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct option among possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.995 in.", "B": "2.005 in.", "C": "1.985 in.", "D": "2.015 in." }, "correct_answer": "A", "explanation": "正确答案A考虑了铜杆在通过开口时的弹性应变恢复。干扰项B利用了'直觉上认为需要稍大开口'的认知偏差，但实际上弹性恢复会使杆径略微增大。干扰项C错误地假设了塑性变形主导过程。干扰项D结合了错误的弹性恢复方向和加工余量考虑。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3819, "question": "Consider a Pb-70% Sn alloy. Determine the amounts and compositions of each microconstituent at 182 degrees C.", "answer": "primary beta: 97.5% sn, % primary beta = 22.8%, eutectic: 61.9% sn, % eutectic = 77.2%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算确定Pb-70% Sn合金在182°C时各微组成物的数量和成分。答案给出了具体的百分比和成分，这表明需要进行数值计算和相图分析来得出结果。 | 知识层次: 题目需要应用杠杆定律进行多步计算，涉及相图分析和成分比例的确定，需要综合分析相图中不同区域的组成和比例关系。虽然不涉及复杂的机理分析或创新设计，但需要一定的概念关联和计算步骤。 | 难度: 在选择题中属于中等偏上难度，需要理解相图概念、杠杆定律计算，并进行多步骤综合分析。题目要求计算两种微组成物的含量和成分，涉及多个计算步骤和概念关联，但选项提供了明确的计算结果，降低了部分难度。", "convertible": true, "correct_option": "primary beta: 97.5% sn, % primary beta = 22.8%, eutectic: 61.9% sn, % eutectic = 77.2%", "choice_question": "For a Pb-70% Sn alloy at 182 degrees C, what are the amounts and compositions of each microconstituent?", "conversion_reason": "The answer is a specific and well-defined set of values, making it suitable for conversion into a multiple-choice question where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "primary beta: 97.5% Sn, % primary beta = 22.8%, eutectic: 61.9% Sn, % eutectic = 77.2%", "B": "primary alpha: 19% Sn, % primary alpha = 22.8%, eutectic: 61.9% Sn, % eutectic = 77.2%", "C": "primary beta: 97.5% Sn, % primary beta = 77.2%, eutectic: 61.9% Sn, % eutectic = 22.8%", "D": "primary alpha: 19% Sn, % primary alpha = 77.2%, eutectic: 97.5% Sn, % eutectic = 22.8%" }, "correct_answer": "A", "explanation": "The correct answer uses the lever rule at 182°C where the eutectic composition is 61.9% Sn and the primary beta phase is 97.5% Sn. Option B incorrectly identifies primary alpha phase which doesn't exist at this temperature. Option C reverses the percentages of the phases. Option D combines both phase identification and percentage errors, creating a plausible-looking but completely wrong scenario.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3961, "question": "A tensile test is performed on a specimen of some metal alloy, and it is found that a true plastic strain of 0.12 is produced when a true stress of 280 MPa is applied. For this alloy, the value of the strain hardening exponent is 0.3 . On the basis of these data what true plastic strain would be expected for a total true plastic stress of 330 MPa ?", "answer": "the true plastic strain expected for a total true plastic stress of 330 \\text{mpa} is 0.383.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求基于给定的材料参数（应变硬化指数、真实塑性应变和真实应力）进行计算，以预测在另一个应力水平下的真实塑性应变。解答过程涉及数值计算和公式应用（如应变硬化公式），最终答案是一个具体的数值结果。 | 知识层次: 题目需要应用应变硬化公式进行多步计算，涉及对公式的理解和变形，以及数值计算能力。虽然不涉及复杂的综合分析或机理解释，但需要将给定的参数正确代入公式并求解，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及真实应力-应变关系、应变硬化指数的应用，以及多步骤计算过程。虽然题目提供了必要的数据，但解题过程需要综合运用这些概念和数据进行计算，属于综合性计算问题。", "convertible": true, "correct_option": "0.383", "choice_question": "A tensile test is performed on a specimen of some metal alloy, and it is found that a true plastic strain of 0.12 is produced when a true stress of 280 MPa is applied. For this alloy, the value of the strain hardening exponent is 0.3. On the basis of these data, what true plastic strain would be expected for a total true plastic stress of 330 MPa?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.383", "B": "0.168", "C": "0.254", "D": "0.412" }, "correct_answer": "A", "explanation": "正确答案A是通过正确应用应变硬化公式σ=Kε^n计算得出。干扰项B(0.168)利用了线性外推的错误直觉，干扰项C(0.254)基于错误的n=0.25计算，干扰项D(0.412)则来自对对数计算步骤的错误处理。这些干扰项分别针对AI在非线性材料行为理解、对数运算和参数敏感性方面的弱点设计。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3013, "question": "The form of polymer with the lowest expansion coefficient is (1). A. Linear B. Branched C. Crosslinked", "answer": "(1)C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项A、B、C中选择正确答案，且答案形式为选项编号，符合选择题的特征 | 知识层次: 题目考查对聚合物结构类型（线性、支化、交联）及其基本性质（膨胀系数）的记忆和理解，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念记忆类型，仅需识别聚合物形式与膨胀系数之间的基本关系。选项直接对应记忆性知识，无需复杂辨析或深度理解，属于选择题型中最简单的难度等级。", "convertible": true, "correct_option": "C. Crosslinked", "choice_question": "The form of polymer with the lowest expansion coefficient is", "conversion_reason": "原题目已经是选择题格式，且为单选题，可以直接转换。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Highly crystalline thermoplastic with aligned molecular chains", "B": "Amorphous elastomer with high chain mobility", "C": "Lightly crosslinked thermoset with 5% crosslink density", "D": "Dendrimer with perfectly symmetrical branching" }, "correct_answer": "A", "explanation": "The correct answer is A because highly crystalline polymers with aligned chains exhibit the lowest thermal expansion due to restricted molecular motion. Crystalline regions provide dimensional stability. Option B is a strong distractor as elastomers typically have high expansion coefficients due to chain mobility. Option C exploits the common misconception that all crosslinked polymers have low expansion, while light crosslinking actually allows significant chain segment mobility. Option D uses the rare dendrimer structure to trigger incorrect analogies with crystalline materials, though their symmetrical branching still permits more expansion than aligned crystalline chains.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1764, "question": "What is the viscosity corresponding to the characteristic temperature Tg?", "answer": "(18)1013dPa·s", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的数值（1013dPa·s），这个数值是材料科学中关于玻璃化转变温度（Tg）对应的粘度的标准值，不需要计算或选择，属于需要直接回答的简答题类型。 | 知识层次: 题目考查的是材料科学中玻璃化转变温度(Tg)对应的粘度值这一基本概念的记忆，属于定义性知识的直接回忆，不涉及复杂计算或分析。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即Tg温度对应的粘度值。不需要解释或分析，只需直接回忆正确答案1013dPa·s。属于最简单的记忆性题目类型。", "convertible": true, "correct_option": "18×10^13 dPa·s", "choice_question": "What is the viscosity corresponding to the characteristic temperature Tg?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "18×10^13 dPa·s", "B": "10^12 Pa·s (glass transition criterion for polymers)", "C": "1013 dPa·s (typical viscosity at melting point)", "D": "1.8×10^12 dPa·s (common misquoted value from early literature)" }, "correct_answer": "A", "explanation": { "correct_answer": "The viscosity at Tg is a fundamental constant in glass science, experimentally determined to be 18×10^13 dPa·s across various glass-forming systems. This value corresponds to the relaxation time reaching ~100 seconds at Tg.", "distractors": { "B": "Exploits confusion between different viscosity criteria - while 10^12 Pa·s is often cited for polymer Tg, it's incorrect for inorganic glasses and lacks the precise 18×10^13 value.", "C": "Uses a realistic viscosity value but at the wrong temperature (melting point instead of Tg), playing on the common misconception that viscosity changes linearly with temperature.", "D": "Capitalizes on a historical misquotation that persists in some references, challenging the examinee's ability to distinguish primary research from secondary sources." } }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 607, "question": "The carbon content of ledeburite is", "answer": "4.3%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的数值答案（4.3%），而不是从多个选项中选择或判断对错，也不需要复杂的计算过程。这符合简答题的特征，即需要直接回答一个具体的问题。 | 知识层次: 题目考查对ledeburite碳含量的基本概念记忆，属于定义性知识的直接回忆，不需要复杂的应用或分析过程。 | 难度: 在选择题型中，该题目仅考察对ledeburite碳含量的基础定义记忆，属于最基本的概念性知识。题目仅要求考生回忆一个具体数值（4.3%），无需任何解释、分析或推理过程，完全符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "4.3%", "choice_question": "The carbon content of ledeburite is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.3%", "B": "2.1%", "C": "0.8%", "D": "6.7%" }, "correct_answer": "A", "explanation": "The correct answer is A (4.3%) because ledeburite is a eutectic mixture of austenite and cementite in the iron-carbon phase diagram, which forms at the eutectic composition of 4.3% carbon. Option B (2.1%) is the maximum solubility of carbon in austenite, creating confusion with the solubility limit. Option C (0.8%) is the eutectoid composition for pearlite formation, exploiting phase diagram similarity confusion. Option D (6.7%) is the carbon content of cementite, designed to trap those who mistake the component for the mixture.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4846, "question": "Predict whether Arsenic (As) will act as a donor or an acceptor when added to Zinc Telluride (ZnTe). Assume that the impurity elements are substitutional.", "answer": "Arsenic will act as an acceptor in ZnTe. Since As is from group VA of the periodic table, it will substitute for Te; furthermore, an As atom has one less valence electron than a Te atom.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求预测砷在碲化锌中的行为，并给出解释。答案需要文字论述和解释，而不是简单的选择或判断。 | 知识层次: 题目需要理解掺杂元素在半导体中的行为，涉及元素周期表分组和价电子数的比较，以及掺杂后对材料电学性能的影响。虽然不涉及复杂计算，但需要综合分析As在ZnTe中的替代位置和电子行为，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要理解多个概念并进行综合分析。题目要求考生不仅知道砷（As）和碲（Te）在周期表中的位置，还需要理解掺杂半导体中施主和受主的概念，以及杂质替代对材料电学性质的影响。此外，题目还要求考生能够将不同知识点关联起来，进行多步推理和判断。因此，该题目在选择题型内属于较高难度。", "convertible": true, "correct_option": "Arsenic will act as an acceptor in ZnTe.", "choice_question": "Predict whether Arsenic (As) will act as a donor or an acceptor when added to Zinc Telluride (ZnTe). Assume that the impurity elements are substitutional.", "conversion_reason": "The answer is a standard concept in materials science, making it suitable for conversion to a multiple-choice format. The correct option can be directly derived from the given answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Acceptor (As substitutes for Te)", "B": "Donor (As substitutes for Zn)", "C": "Amphoteric (As can substitute for both sites)", "D": "Neutral (As forms an isoelectronic center)" }, "correct_answer": "A", "explanation": "Correct answer is A because As has one less valence electron than Te (group V vs VI), creating hole states. B is wrong but tempting as As is in group V like N in GaN (common donor analogy trap). C is plausible but incorrect as As-Te substitution is energetically favored. D exploits the isoelectronic trap concept which doesn't apply here.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2265, "question": "If a new phase in a solid-state phase transformation precipitates from the parent phase as spherical particles, and the change in free energy per unit volume is $10^{8}\\\\mathrm{~J~}\\\\cdot\\\\mathrm{~m~}^{-3}$, the specific surface energy is $1~\\\\mathrm{J}\\\\cdot\\\\mathrm{m}^{-2}$, and the strain energy is negligible, calculate the diameter of the new phase particles when the surface energy is $1\\\\%$ of the volume free energy.", "answer": "Diameter $2r=6\\\\times10^{-6}\\\\mathrm{~m~}$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解新相粒子的直径，答案是一个具体的数值结果（Diameter $2r=6\\times10^{-6}\\mathrm{~m~}$），符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要理解自由能变化、表面能的概念，并应用相关公式进行计算。虽然计算过程不复杂，但需要综合分析自由能和表面能的关系，并正确应用公式求解粒子直径。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及固体相变中的自由能变化、表面能和应变能的概念，并要求计算新相粒子的直径。虽然题目提供了具体数值，但需要学生理解表面能与体积自由能之间的关系，并正确应用公式进行计算。解题步骤包括理解题意、建立数学模型、代入数值计算，属于多步骤计算过程，但相对于更复杂的多变量计算问题，难度适中。", "convertible": true, "correct_option": "Diameter $2r=6\\times10^{-6}\\mathrm{~m~}$", "choice_question": "If a new phase in a solid-state phase transformation precipitates from the parent phase as spherical particles, and the change in free energy per unit volume is $10^{8}\\mathrm{~J~}\\cdot\\mathrm{~m~}^{-3}$, the specific surface energy is $1~\\mathrm{J}\\cdot\\mathrm{m}^{-2}$, and the strain energy is negligible, what is the diameter of the new phase particles when the surface energy is $1\\%$ of the volume free energy?", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format with the correct option being the provided answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6×10⁻⁶ m", "B": "3×10⁻⁸ m", "C": "1.2×10⁻⁵ m", "D": "6×10⁻⁹ m" }, "correct_answer": "A", "explanation": "The correct answer is A (6×10⁻⁶ m) derived from balancing surface energy (4πr²γ) at 1% of volume free energy (4/3πr³ΔGv). Option B (3×10⁻⁸ m) is a common error from misplacing the decimal in surface energy calculation. Option C (1.2×10⁻⁵ m) results from incorrectly doubling the correct radius. Option D (6×10⁻⁹ m) is a unit confusion trap between meters and nanometers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 812, "question": "What are the necessary conditions for an alloy to undergo precipitation hardening?", "answer": "The necessary condition for precipitation hardening to occur is the availability of a supersaturated solid solution to facilitate the precipitation of a second phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释合金发生沉淀硬化的必要条件，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对沉淀硬化基本条件的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并描述\"过饱和固溶体\"和\"第二相析出\"这两个关键概念之间的关系，而不仅仅是简单的定义复述。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "The availability of a supersaturated solid solution to facilitate the precipitation of a second phase", "choice_question": "What is the necessary condition for an alloy to undergo precipitation hardening?", "conversion_reason": "The answer is a standard concept that can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The alloy must have a solubility limit that decreases with decreasing temperature", "B": "The alloy must contain at least 5% of a secondary alloying element", "C": "The alloy must be quenched from above its recrystallization temperature", "D": "The alloy must exhibit complete solid solubility at all temperatures" }, "correct_answer": "A", "explanation": "Correct answer A is essential because precipitation hardening requires a decreasing solubility limit with temperature to create supersaturation. Option B is a cognitive bias trap - while many precipitation-hardenable alloys meet this condition, it's not fundamentally required. Option C exploits confusion between recrystallization and solution treatment temperatures. Option D is the exact opposite of what's needed, creating a counterintuitive trap for models relying on general solubility knowledge.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 651, "question": "Describe the main strengthening mechanisms that may be employed to strengthen the Al-5%Al2O3 composite material", "answer": "The strengthening mechanisms for the Al-5%Al2O3 composite material are work hardening, fine grain strengthening, and dispersion strengthening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述主要的强化机制，需要文字解释和论述，而不是选择、判断或计算。答案提供了详细的文字说明，符合简答题的特征。 | 知识层次: 题目要求描述Al-5%Al2O3复合材料的强化机制，涉及多个强化机制（加工硬化、细晶强化、弥散强化）的综合分析，需要理解这些机制在复合材料中的具体应用和相互作用，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念（如工作硬化、细晶强化和弥散强化）并进行综合分析。虽然题目涉及多个强化机制，但在选择题型中只需识别正确选项，无需深入论述各机制的具体原理或计算过程。", "convertible": true, "correct_option": "work hardening, fine grain strengthening, and dispersion strengthening", "choice_question": "Which of the following are the main strengthening mechanisms that may be employed to strengthen the Al-5%Al2O3 composite material?", "conversion_reason": "The answer is a standard set of terms (work hardening, fine grain strengthening, and dispersion strengthening) which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "work hardening, fine grain strengthening, and dispersion strengthening", "B": "solid solution strengthening, precipitation hardening, and twinning", "C": "strain rate sensitivity, texture strengthening, and phase transformation", "D": "Hall-Petch strengthening, Orowan strengthening, and thermal expansion mismatch" }, "correct_answer": "A", "explanation": "The correct answer is A because Al-5%Al2O3 is a metal matrix composite where the primary strengthening mechanisms are work hardening (from the metal matrix), fine grain strengthening (from controlled processing), and dispersion strengthening (from the Al2O3 particles). Option B is incorrect because solid solution strengthening and precipitation hardening are not applicable here - the Al2O3 particles are insoluble precipitates, not solute atoms. Option C is incorrect as strain rate sensitivity and texture strengthening are not primary mechanisms for this composite, and no phase transformation occurs. Option D is partially correct but misleading - while Hall-Petch and Orowan strengthening are relevant, thermal expansion mismatch is not a strengthening mechanism but rather a source of residual stresses.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1205, "question": "In homogeneous nucleation, assuming the nucleus shape is a cube with side length a, given σ and ΔGv, find the critical nucleation work", "answer": "The critical nucleation work is 32σ³/ΔGv²", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的参数（σ和ΔGv）和公式计算临界成核功，答案是一个具体的数值表达式（32σ³/ΔGv²），符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要理解均相成核的基本原理，应用临界成核功的公式，并进行适当的代数运算。虽然计算过程不算复杂，但需要将几何形状（立方体）与表面能和体积自由能变化关联起来，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解均匀成核理论中的临界成核功概念，并能正确应用立方体几何关系（表面积与体积计算）。题目要求将界面能σ和体积自由能变化ΔGv进行关联，并完成多步推导计算（包括求导求极值等步骤）。虽然选择题提供了正确选项，但考生仍需具备综合分析能力才能确认答案的正确性，这超过了简单概念识别的层次。", "convertible": true, "correct_option": "32σ³/ΔGv²", "choice_question": "In homogeneous nucleation, assuming the nucleus shape is a cube with side length a, given σ and ΔGv, the critical nucleation work is:", "conversion_reason": "The answer is a specific mathematical expression, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "32σ³/ΔGv²", "B": "16σ³/ΔGv²", "C": "24σ²/ΔGv", "D": "8σ³/ΔGv²" }, "correct_answer": "A", "explanation": "The correct answer is A because for a cubic nucleus, the critical nucleation work is derived from balancing surface energy (6a²σ) and volume free energy (a³ΔGv), leading to a critical side length a* = -4σ/ΔGv. Substituting into ΔG* = 3a*²σ gives 32σ³/ΔGv². Option B is a common error from misapplying the spherical nucleus formula. Option C exploits confusion between energy and force dimensions. Option D is a tempting simplification error from ignoring the cubic geometry.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 73, "question": "Why are non-stoichiometric compounds all n-type or p-type semiconductor materials?", "answer": "Due to anion vacancies and interstitial cations leading to an excess of metal ions, metal-excess (n-type) semiconductors are formed; cation vacancies and interstitial anions leading to an excess of anions form anion-excess (p-type) semiconductors.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释非化学计量化合物为何都是n型或p型半导体材料，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释非化学计量化合物为何都是n型或p型半导体材料，涉及缺陷化学、半导体类型与缺陷类型之间的关联机制，需要综合运用多个概念并进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Due to anion vacancies and interstitial cations leading to an excess of metal ions, metal-excess (n-type) semiconductors are formed; cation vacancies and interstitial anions leading to an excess of anions form anion-excess (p-type) semiconductors.", "choice_question": "Why are non-stoichiometric compounds all n-type or p-type semiconductor materials?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": "None", "perplexity_level": "None", "perplexity_reason": "None", "missing_info": "None" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Due to anion vacancies and interstitial cations leading to an excess of metal ions, forming n-type semiconductors; cation vacancies and interstitial anions leading to an excess of anions form p-type semiconductors", "B": "Because non-stoichiometry always creates free electrons regardless of defect type, making all materials n-type", "C": "The charge neutrality condition forces all non-stoichiometric compounds to become either electron or hole conductors", "D": "Non-stoichiometric defects introduce mid-gap states that can act as either donors or acceptors" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the two fundamental defect mechanisms creating n-type (metal excess) and p-type (anion excess) semiconductors. Distractor B exploits the common misconception that non-stoichiometry always means electron excess. Option C sounds plausible but incorrectly generalizes the charge neutrality principle. Distractor D describes a real phenomenon (mid-gap states) but inaccurately applies it to explain the exclusive n/p-type behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1270, "question": "When a spherical crystal embryo with radius r appears in an undercooled liquid, what happens to the number of nucleation events as r* decreases?", "answer": "Increases", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释当球形晶胚半径r*减小时成核事件数量的变化情况，答案需要文字解释和论述，而非简单的选择、判断或计算。 | 知识层次: 题目涉及晶体成核的基本原理和临界半径的概念，需要理解成核事件与临界半径之间的关系，并进行一定的综合分析。虽然不涉及复杂的计算或深度推理，但需要将多个概念关联起来进行解释，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解晶体成核理论中的临界半径概念(r*)及其与过冷液体的关系，并能综合分析半径减小对成核事件数量的影响。题目涉及多步概念关联，但作为选择题只需选择正确趋势（增加），不需要展开论述。", "convertible": true, "correct_option": "Increases", "choice_question": "When a spherical crystal embryo with radius r appears in an undercooled liquid, what happens to the number of nucleation events as r* decreases?", "conversion_reason": "The answer is a standard term that can be presented as a single correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases", "B": "Decreases", "C": "Remains constant", "D": "First increases then decreases" }, "correct_answer": "A", "explanation": "The correct answer is A because as the critical radius r* decreases, the energy barrier for nucleation decreases, leading to more nucleation events. Option B is a common misconception due to confusing nucleation rate with growth rate. Option C exploits the intuition that thermodynamic equilibrium might stabilize nucleation events. Option D is designed to trap those who consider the full range of undercooling effects but fail to focus on the specific relationship between r* and nucleation events.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4558, "question": "Compute the corrosion potential for this reaction given the following corrosion data: For Metal M: V(M/M2+)=-0.47 V, i0=5x10-10 A/cm2, β=+0.15; For Hydrogen: V(H+/H2)=0 V, i0=2x10-9 A/cm2, β=-0.12.", "answer": "the corrosion potential for this reaction is -0.169 v.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的腐蚀数据（电位、交换电流密度、塔菲尔斜率）进行数值计算，应用电化学腐蚀相关公式来求解腐蚀电位。答案是一个具体的数值（-0.169 V），这表明解答过程涉及计算步骤和公式应用，而非选择、判断或文字解释。 | 知识层次: 题目需要应用腐蚀电化学的基本公式进行多步计算，涉及腐蚀电位计算、交换电流密度和塔菲尔斜率的应用，需要综合分析金属和氢电极的反应参数，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解腐蚀电位的计算原理，综合运用能斯特方程和塔菲尔方程进行多步计算，并正确关联金属和氢的不同电化学参数。虽然选择题型提供了正确选项，但解题过程涉及多个变量和概念的综合分析，对学生的应用能力要求较高。", "convertible": true, "correct_option": "-0.169 v", "choice_question": "Given the following corrosion data for Metal M: V(M/M2+)=-0.47 V, i0=5x10-10 A/cm2, β=+0.15; and for Hydrogen: V(H+/H2)=0 V, i0=2x10-9 A/cm2, β=-0.12, what is the corrosion potential for this reaction?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-0.169 V", "B": "-0.247 V", "C": "-0.412 V", "D": "+0.032 V" }, "correct_answer": "A", "explanation": "The correct answer is A (-0.169 V) calculated using the mixed potential theory by equating the anodic and cathodic current densities. Option B (-0.247 V) is designed to exploit cognitive bias by reversing the β signs, a common mistake when applying Tafel equations. Option C (-0.412 V) traps those who incorrectly assume the corrosion potential should be closer to the metal's equilibrium potential. Option D (+0.032 V) is a professional intuition trap, mimicking cases where hydrogen evolution dominates but miscalculating the potential shift due to exchange current density differences.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4187, "question": "To what group in the periodic table would an element with atomic number 114 belong?", "answer": "From the periodic table the element having atomic number 114 would belong to group IVA. Ds, having an atomic number of 110 lies below Pt in the periodic table and in the rightmost column of group VIII. Moving four columns to the right puts element 114 under \\mathrm{Pb} and in group IVA.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释元素114在周期表中的归属，答案提供了详细的文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目考查对元素周期表中元素分类的基本概念的记忆和理解，只需根据原子数定位元素在周期表中的位置即可回答，无需复杂计算或分析。 | 难度: 在选择题型中，该题目需要考生掌握元素周期表的分组原则和原子序数与元素位置的关系，属于概念解释和描述的难度级别。虽然需要一定的记忆和理解，但不需要复杂的分析或推理步骤。", "convertible": true, "correct_option": "group IVA", "choice_question": "To which group in the periodic table would an element with atomic number 114 belong?", "conversion_reason": "The answer is a standard term (group IVA) from the periodic table, which can be presented as a clear option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "group IVA", "B": "group IIB", "C": "group VIIA", "D": "group IIIB" }, "correct_answer": "A", "explanation": "Element 114 (Flerovium) belongs to group IVA due to its electron configuration ending in p². Option B exploits the common mistake of confusing it with zinc group elements. Option C targets the tendency to overcount valence electrons in heavy elements. Option D creates confusion between main group and transition metal classifications.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4929, "question": "Briefly describe the Meissner effect.", "answer": "The Meissner effect is a phenomenon found in superconductors wherein, in the superconducting state, the material is diamagnetic and completely excludes any external magnetic field from its interior. In the normal conducting state complete magnetic flux penetration of the material occurs.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述Meissner效应，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对Meissner效应的基本定义和现象描述，属于基础概念的记忆和理解范畴，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目要求考生对Meissner效应进行概念解释和描述，而非仅回答基本定义或进行复杂概念体系阐述。题目涉及对超导体在超导态和正常态下对磁场响应的描述，属于中等难度的概念理解题。", "convertible": true, "correct_option": "The Meissner effect is a phenomenon found in superconductors wherein, in the superconducting state, the material is diamagnetic and completely excludes any external magnetic field from its interior. In the normal conducting state complete magnetic flux penetration of the material occurs.", "choice_question": "Which of the following best describes the Meissner effect?", "conversion_reason": "The answer is a standard definition of the Meissner effect, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Complete expulsion of magnetic fields below Tc due to perfect diamagnetism in the superconducting state", "B": "Partial magnetic flux penetration accompanied by reduced resistivity in type-II superconductors", "C": "Temperature-dependent magnetic susceptibility reversal at the Curie point", "D": "Formation of Cooper pairs leading to zero electrical resistance" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the Meissner effect's key feature: perfect diamagnetism and complete field expulsion below Tc. Option B combines correct type-II superconductor behavior (partial flux penetration) with the wrong phenomenon (resistivity change). Option C describes ferromagnetic-paramagnetic transition, not superconductivity. Option D describes the microscopic origin of superconductivity but not the macroscopic Meissner effect. Advanced AIs might confuse B (partial truth) or D (related concept) with the actual Meissner effect definition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3906, "question": "Some metal is known to have a cubic unit cell with an edge length of 0.437 nm. In addition, it has a density of 4.37 g/cm3 and an atomic weight of 54.85 g/mol. Determine the atomic radius of the metal.", "answer": "The metal has an atomic radius of 0.155 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（如单位晶胞边长、密度和原子量之间的关系）来确定金属的原子半径，答案是一个具体的数值结果（0.155 nm），符合计算题的特征。 | 知识层次: 题目需要多步计算（包括密度公式应用、单位换算和几何关系推导），并需要将晶体结构几何知识与材料物理性质（密度、原子量）关联起来综合分析。虽然不涉及复杂机理或创新设计，但思维过程要求高于简单套用公式。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念并进行比较分析。题目涉及单位晶胞边长、密度、原子量等多个参数的综合计算，要求考生掌握晶体结构、密度计算、原子半径与晶格参数的关系等知识点，并进行多步推导和计算。虽然选择题提供了正确选项，但解题过程仍需要较高的综合分析能力和计算技巧。", "convertible": true, "correct_option": "0.155 nm", "choice_question": "Some metal is known to have a cubic unit cell with an edge length of 0.437 nm. In addition, it has a density of 4.37 g/cm3 and an atomic weight of 54.85 g/mol. Determine the atomic radius of the metal from the following options:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.155 nm", "B": "0.189 nm", "C": "0.137 nm", "D": "0.172 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.155 nm) calculated using the relationship between edge length and atomic radius for a cubic unit cell. Option B (0.189 nm) is designed to exploit the common mistake of confusing face-centered cubic with body-centered cubic packing. Option C (0.137 nm) targets the error of using simple cubic packing assumptions. Option D (0.172 nm) is calculated by incorrectly using the density formula without considering the correct unit cell geometry.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 791, "question": "2. The concentration of structural defects in non-stoichiometric compounds is related to the nature and pressure of the surrounding atmosphere. Analyze how the density of the non-stoichiometric compounds Fe1-xO and Zn1+xO will change if the partial pressure of the surrounding oxygen atmosphere is increased.", "answer": "If the partial pressure of the surrounding oxygen atmosphere is increased, the value of x in the non-stoichiometric compound Fe1-xO increases, leading to an increase in the concentration of cation vacancies, which results in a decrease in the density of Fe1-xO. Similarly, if the partial pressure of the surrounding oxygen atmosphere is increased, the value of x in the non-stoichiometric compound Zn1+xO decreases, leading to a reduction in the concentration of interstitial cations, which also results in a decrease in the density of Zn1+xO.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析非化学计量化合物中结构缺陷浓度与周围氧气分压的关系，并解释其对密度的影响。答案需要详细的文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求分析非化学计量化合物中结构缺陷浓度与周围氧气分压的关系，并解释其对密度的影响。这需要综合运用缺陷化学、非化学计量化合物的性质以及环境条件对材料性能的影响等多方面知识，进行推理分析和机理解释。思维过程涉及多个概念的关联和综合分析，属于较高层次的认知要求。 | 难度: 在选择题型中，该题目属于最高难度等级。它要求考生不仅理解非化学计量化合物的基本概念，还需要深入掌握缺陷化学的机理，能够分析氧分压变化对两种不同类型非化学计量化合物（Fe1-xO和Zn1+xO）缺陷浓度和密度的不同影响。解题需要综合运用多个知识点，包括缺陷类型、缺陷反应方程、质量作用定律等，并进行复杂的推理分析。此外，题目涉及两种化合物的对比分析，增加了思维复杂度，完全符合选择题型中\"复杂现象全面分析\"的最高难度标准。", "convertible": true, "correct_option": "If the partial pressure of the surrounding oxygen atmosphere is increased, the value of x in the non-stoichiometric compound Fe1-xO increases, leading to an increase in the concentration of cation vacancies, which results in a decrease in the density of Fe1-xO. Similarly, if the partial pressure of the surrounding oxygen atmosphere is increased, the value of x in the non-stoichiometric compound Zn1+xO decreases, leading to a reduction in the concentration of interstitial cations, which also results in a decrease in the density of Zn1+xO.", "choice_question": "How will the density of the non-stoichiometric compounds Fe1-xO and Zn1+xO change if the partial pressure of the surrounding oxygen atmosphere is increased?", "conversion_reason": "The answer is a specific and detailed explanation that can be directly used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Both Fe1-xO and Zn1+xO will show decreased density due to increased cation vacancy concentration", "B": "Fe1-xO density decreases while Zn1+xO density increases, due to opposite defect formation mechanisms", "C": "Both compounds will show increased density due to enhanced oxygen incorporation", "D": "Fe1-xO density increases due to cation vacancies while Zn1+xO density decreases due to interstitial cations" }, "correct_answer": "A", "explanation": "Correct answer A accounts for the fact that increasing oxygen partial pressure creates cation vacancies in both systems, though through different defect reactions (metal deficiency in Fe1-xO vs oxygen excess in Zn1+xO). Option B is a common mistake where AI might assume opposite trends due to different defect types. Option C exploits the intuitive but incorrect assumption that more oxygen always increases density. Option D reverses the actual density effects by confusing defect types with their structural impacts.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1632, "question": "In face-centered cubic crystals, the partial dislocation caused by (6)__ is called the Shockley partial dislocation", "answer": "(6) non-uniform slip", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（non-uniform slip）来完整句子，这属于需要提供简短文字答案的简答题类型，而不是从多个选项中选择或进行判断。 | 知识层次: 题目考查的是面心立方晶体中部分位错的基本概念和分类，需要记忆和理解Shockley部分位错的定义及其形成原因，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即Shockley partial dislocation的定义和成因。正确选项\"non-uniform slip\"是直接对应教材中的定义性知识，无需复杂推理或概念关联。属于最基础的定义简答层级，符合等级1标准。", "convertible": true, "correct_option": "non-uniform slip", "choice_question": "In face-centered cubic crystals, the partial dislocation caused by (6)__ is called the Shockley partial dislocation", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "non-uniform slip", "B": "lattice distortion", "C": "stacking fault energy", "D": "Burgers vector dissociation" }, "correct_answer": "A", "explanation": "The correct answer is A because Shockley partial dislocations specifically result from non-uniform slip in FCC crystals, where the dislocation splits into two partials with a stacking fault in between. Option B exploits the common misconception that any lattice distortion can create partial dislocations. Option C uses stacking fault energy which is related but not the direct cause, creating a surface-level association trap. Option D describes a process that occurs after partial dislocation formation, not the initiating mechanism, playing on temporal sequence confusion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4246, "question": "(b) What is the driving force for steady-state diffusion?", "answer": "The driving force for steady-state diffusion is the concentration gradient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述驱动力的概念，答案是一个简短的文字解释，没有涉及计算或选择选项。 | 知识层次: 题目考查对扩散驱动力的基本概念记忆，仅需回答浓度梯度这一基本原理，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即稳态扩散的驱动力是浓度梯度这一基本原理。题目不涉及复杂概念体系或需要解释描述，属于最基础的定义简答级别，因此难度等级为1。", "convertible": true, "correct_option": "The concentration gradient", "choice_question": "What is the driving force for steady-state diffusion?", "conversion_reason": "The answer is a standard concept (concentration gradient) which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The concentration gradient", "B": "The chemical potential gradient", "C": "The temperature gradient", "D": "The stress gradient" }, "correct_answer": "A", "explanation": "The correct answer is A because steady-state diffusion is fundamentally driven by the concentration gradient according to Fick's first law. Option B is a high-level trap that exploits the AI's knowledge of thermodynamic driving forces, while in reality chemical potential gradient drives non-steady-state diffusion. Option C targets the common confusion between diffusion and thermal conduction phenomena. Option D exploits material scientists' intuition about stress-induced diffusion, which is a secondary effect requiring specific conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2962, "question": "In the seven polymorphic forms of $\\\\mathrm{{SiO}}_{2}$, there are two types of transformations: one is displacive transformation, and the other is reconstructive transformation. The activation energy required for displacive transformation is _____ that for reconstructive transformation. (A) greater than (B) less than (C) equal to", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（A、B、C）中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对两种相变类型（位移型相变和重构型相变）的基本概念记忆，特别是它们所需活化能的相对大小，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目需要理解两种相变类型（位移型相变和重构型相变）的基本概念，并比较它们的活化能大小。虽然涉及两个概念，但题目直接给出了明确的比较关系，不需要复杂的分析或推理过程，属于概念理解和简单辨析的难度级别。", "convertible": true, "correct_option": "B", "choice_question": "In the seven polymorphic forms of $\\mathrm{{SiO}}_{2}$, there are two types of transformations: one is displacive transformation, and the other is reconstructive transformation. The activation energy required for displacive transformation is _____ that for reconstructive transformation.", "conversion_reason": "The original question is already in a single-choice format with clear options and a correct answer provided.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy is determined by the degree of bond angle distortion during transformation", "B": "The activation energy is proportional to the density difference between polymorphic forms", "C": "The activation energy depends on the coordination number change during phase transition", "D": "The activation energy is inversely related to the thermal expansion coefficient difference" }, "correct_answer": "C", "explanation": "Correct answer C is based on the fundamental principle that reconstructive transformations involving coordination number changes require breaking and reforming primary bonds, which demands higher activation energy than displacive transformations that only involve bond angle distortions. Option A is a cognitive bias trap - while bond angle distortion is relevant for displacive transformations, it doesn't determine the activation energy difference. Option B exploits numerical reasoning bias by suggesting a plausible but incorrect proportional relationship. Option D creates a multi-parameter verification trap by introducing thermal expansion coefficient which is irrelevant to activation energy determination.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4454, "question": "Cite two properties that may be improved by crystallization.", "answer": "Two properties that may be improved by crystallization are (1) a lower coefficient of thermal expansion, and (2) higher strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举两个可能通过结晶改善的性能，答案需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查对结晶化改善材料性能这一基本概念的简单列举和记忆，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需回忆并列举两个可能通过结晶改善的性质。题目不涉及概念解释或复杂体系阐述，解题步骤简单直接，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "a lower coefficient of thermal expansion and higher strength", "choice_question": "Which of the following are properties that may be improved by crystallization?", "conversion_reason": "The original short answer question asks for two specific properties improved by crystallization, which can be converted into a multiple-choice question by listing possible properties and including the correct ones as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Lower coefficient of thermal expansion and higher strength", "B": "Increased ductility and reduced hardness", "C": "Higher electrical conductivity and improved fracture toughness", "D": "Enhanced creep resistance and decreased yield strength" }, "correct_answer": "A", "explanation": "Crystallization typically improves strength and reduces thermal expansion due to ordered atomic structure. Option B is wrong because crystallization usually reduces ductility. Option C is misleading as electrical conductivity often decreases in crystalline vs amorphous states. Option D contains a contradiction - creep resistance improves but yield strength increases with crystallization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2766, "question": "What is the critical resolved shear stress for crystal slip?", "answer": "The minimum resolved shear stress required for alternate slip in the slip systems of a crystal is called the critical resolved shear stress.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释\"critical resolved shear stress\"的定义，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即临界分切应力的定义，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察对\"临界分切应力\"这一基础概念的定义记忆，属于直接复述教材定义的最简单类型。题目仅要求识别正确描述定义的选项，无需解释或应用概念，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The minimum resolved shear stress required for alternate slip in the slip systems of a crystal is called the critical resolved shear stress.", "choice_question": "What is the critical resolved shear stress for crystal slip?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The minimum resolved shear stress required for alternate slip in the slip systems of a crystal", "B": "The maximum shear stress a crystal can withstand before fracture occurs", "C": "The stress at which dislocation multiplication becomes the dominant deformation mechanism", "D": "The yield strength of a single crystal along its slip direction" }, "correct_answer": "A", "explanation": "The correct answer is A because it precisely defines the critical resolved shear stress as the minimum stress needed to initiate slip. Option B is incorrect as it describes fracture stress rather than slip initiation. Option C is a cognitive bias trap, confusing critical resolved shear stress with the stress for dislocation multiplication. Option D exploits professional intuition by equating it with yield strength, which is a macroscopic property rather than the microscopic slip initiation criterion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 291, "question": "Analyze the influence of surface energy on the thermodynamics of solid-state phase transformations", "answer": "The surface of a substance has surface tension α. To reversibly increase the surface area dA under constant temperature and pressure, work αdA is required. Since the work required equals the increase in the system's free energy, and this increase is due to the enlargement of the system's surface area, it is termed surface free energy or surface energy. Surface energy can influence the magnitude of the phase transformation driving force.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析表面能对固态相变热力学的影响，答案提供了详细的文字解释和论述，没有涉及选择题、判断题或计算题的特征。 | 知识层次: 题目要求分析表面能对固态相变热力学的影响，涉及表面自由能的概念、热力学原理的应用，以及相变驱动力变化的解释。这需要综合运用多个概念，进行推理分析和机理解释，思维深度较高。 | 难度: 在选择题型中，该题目要求考生综合运用表面能、热力学自由能以及相变驱动机理等复杂概念，并进行深度推理分析。题目不仅涉及基本概念的定义（如表面能的计算），还需要理解这些概念如何影响固态相变的热力学过程。这种需要多知识点综合运用和机理深度解释的题目，在选择题型中属于最高难度等级。", "convertible": true, "correct_option": "The surface of a substance has surface tension α. To reversibly increase the surface area dA under constant temperature and pressure, work αdA is required. Since the work required equals the increase in the system's free energy, and this increase is due to the enlargement of the system's surface area, it is termed surface free energy or surface energy. Surface energy can influence the magnitude of the phase transformation driving force.", "choice_question": "Which of the following best describes the influence of surface energy on the thermodynamics of solid-state phase transformations?", "conversion_reason": "The answer is a standard explanation that can be converted into a correct option for a multiple-choice question. The question can be rephrased to ask for the best description from given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Surface energy creates an additional energy barrier that must be overcome for nucleation, effectively reducing the driving force for phase transformation", "B": "Surface energy directly alters the bulk Gibbs free energy difference between phases, making it the dominant factor in transformation kinetics", "C": "Surface energy only affects the kinetics of phase transformations by modifying diffusion coefficients at interfaces", "D": "Surface energy has negligible effect because its contribution scales with surface area while bulk free energy scales with volume" }, "correct_answer": "A", "explanation": "Correct answer A captures the dual role of surface energy in both creating nucleation barriers and influencing the net driving force. Option B is a common misconception - surface energy doesn't alter bulk Gibbs energy but creates interfacial energy. Option C exploits confusion between surface energy's thermodynamic vs kinetic effects. Option D uses a partially correct scaling argument but ignores that surface effects become critical at nanoscale where surface-to-volume ratios are large.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 406, "question": "Tie line", "answer": "Tie line: the line connecting the composition points of two equilibrium phases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Tie line\"进行文字解释和论述，答案是一个定义性的陈述，不需要计算或选择 | 知识层次: 题目考查对\"Tie line\"这一基本概念的定义记忆和理解，属于相图分析中的基础术语，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆并识别\"Tie line\"的基本定义，属于最基础的概念记忆层次。题目仅涉及单一概念的简单描述，不需要解释或比较多个概念，解题步骤极为简单，符合选择题型中最基础的难度等级。", "convertible": true, "correct_option": "the line connecting the composition points of two equilibrium phases", "choice_question": "What is a tie line?", "conversion_reason": "The answer is a standard definition that can be presented as one of multiple options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "the line connecting the composition points of two equilibrium phases", "B": "the boundary between single-phase and two-phase regions in a phase diagram", "C": "the line indicating the maximum solubility limit in an alloy system", "D": "the path of phase transformation during continuous cooling" }, "correct_answer": "A", "explanation": "The correct answer is A because a tie line specifically connects the compositions of two coexisting phases in equilibrium. Option B is a cognitive bias trap - while related to phase boundaries, it incorrectly describes the lever rule application region. Option C exploits material science intuition by referencing a real but different concept (solvus line). Option D is a multi-level trap combining correct phase transformation concepts but misapplying them to isothermal conditions where tie lines operate.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3575, "question": "Aluminum foil used for storing food weighs about 0.3g per square inch. How many atoms of aluminum are contained in one square inch of foil?", "answer": "6.69 × 10^{21} atoms", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及单位转换和摩尔计算，最终给出具体的数值答案。 | 知识层次: 题目需要进行基本的单位转换和摩尔计算，涉及简单的公式应用和数值计算，属于直接套用基本概念和公式的范畴。 | 难度: 在选择题中属于简单应用难度，需要应用摩尔质量和阿伏伽德罗常数的基本公式进行计算，但步骤较为直接，仅涉及单位转换和简单乘法运算。", "convertible": true, "correct_option": "6.69 × 10^{21} atoms", "choice_question": "Aluminum foil used for storing food weighs about 0.3g per square inch. How many atoms of aluminum are contained in one square inch of foil?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.69 × 10^{21} atoms", "B": "3.34 × 10^{21} atoms", "C": "1.34 × 10^{22} atoms", "D": "2.67 × 10^{21} atoms" }, "correct_answer": "A", "explanation": "The correct answer is calculated by first determining the number of moles of aluminum in 0.3g (0.3g / 26.98 g/mol ≈ 0.0111 mol), then multiplying by Avogadro's number (0.0111 mol × 6.022 × 10^{23} atoms/mol ≈ 6.69 × 10^{21} atoms). Option B is half the correct value, exploiting a common error of forgetting to fully convert grams to moles. Option C is double the correct value, targeting those who might confuse the atomic mass unit conversion. Option D is one-quarter the correct value, designed to catch those who might incorrectly halve the calculation twice.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3502, "question": "What are the process characteristics of high-speed steel?", "answer": "Process characteristics of high-speed steel: a) Two-stage preheating: reduces thermal stress, minimizes deformation and cracking. b) High quenching temperature: ensures full dissolution of W and V into austenite, allowing alloy carbides to precipitate during tempering, thereby ensuring red hardness. c) Graded quenching: reduces deformation and cracking. d) 560‰ tempering: achieves maximum hardness with secondary hardening and secondary quenching phenomena. e) Triple tempering: reduces retained austenite from over 20% after quenching to approximately 1%–2%.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释高速钢的工艺特性，答案提供了详细的文字描述和论述，符合简答题的特征 | 知识层次: 题目要求解释高速钢的工艺特性，涉及多个工艺步骤（如预热、淬火、回火等）及其原理，需要将不同工艺步骤与材料性能关联起来进行综合分析。虽然不涉及复杂计算，但需要对工艺参数和材料行为有较深入的理解和关联分析。 | 难度: 在选择题型内，该题目属于较高难度，因为它要求考生不仅理解高速钢的基本特性，还需要掌握其具体的工艺特点及其背后的原理。题目涉及多个工艺步骤（如两段预热、高淬火温度、分级淬火、560‰回火和三次回火），每个步骤都有其特定的目的和效果，考生需要综合分析这些步骤之间的关系及其对材料性能的影响。此外，题目还要求考生能够理解并关联诸如热应力、变形、裂纹、红硬性、二次硬化等专业概念，这需要较深的知识掌握和综合分析能力。因此，在选择题型内，该题目属于多角度分析论述的难度等级。", "convertible": true, "correct_option": "a) Two-stage preheating: reduces thermal stress, minimizes deformation and cracking. b) High quenching temperature: ensures full dissolution of W and V into austenite, allowing alloy carbides to precipitate during tempering, thereby ensuring red hardness. c) Graded quenching: reduces deformation and cracking. d) 560‰ tempering: achieves maximum hardness with secondary hardening and secondary quenching phenomena. e) Triple tempering: reduces retained austenite from over 20% after quenching to approximately 1%–2%.", "choice_question": "Which of the following describes the process characteristics of high-speed steel?", "conversion_reason": "The answer is a detailed list of standard process characteristics, which can be converted into a multiple-choice question format by presenting these characteristics as options and asking the examinee to select the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Two-stage preheating at 400°C and 800°C reduces thermal stress by matching thermal expansion coefficients of alloy carbides", "B": "Quenching from 1220-1250°C ensures complete dissolution of Cr and Mo into austenite for maximum hardness", "C": "Triple tempering at 300°C effectively reduces retained austenite below 5% through martensitic transformation", "D": "Secondary hardening occurs due to precipitation of M7C3 carbides during tempering at 560°C" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual mechanism where two-stage preheating minimizes thermal stress by gradual heating. B is incorrect because it mentions Cr and Mo instead of W and V. C is wrong as 300°C is too low for effective austenite reduction. D contains the wrong carbide type (M7C3 instead of MC/M2C). All incorrect options exploit common material science misconceptions about high-speed steel processing.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4567, "question": "Briefly describe the impressed current technique used for galvanic protection.", "answer": "An impressed current from an external dc power source provides excess electrons to the metallic structure to be protected.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述一种技术（impressed current technique），答案以文字解释的形式给出，符合简答题的特征。 | 知识层次: 题目考查对电化学保护技术中\"外加电流法\"基本概念的记忆和理解，仅需描述其基本原理和外部电源的作用，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别关于外加电流阴极保护技术的基本定义和原理。正确选项直接给出了该技术的核心概念描述，不需要进行复杂的分析或比较。这属于最基础的概念记忆层次，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "An impressed current from an external dc power source provides excess electrons to the metallic structure to be protected.", "choice_question": "Which of the following best describes the impressed current technique used for galvanic protection?", "conversion_reason": "The answer is a standard description of the impressed current technique, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An impressed current from an external dc power source provides excess electrons to the metallic structure to be protected", "B": "A sacrificial anode naturally generates sufficient current to polarize the protected structure cathodically", "C": "The technique utilizes alternating current to create an oscillating protective potential field", "D": "It works by matching the galvanic series potential of the structure with an external electrode" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the impressed current technique where an external DC power source provides electrons for cathodic protection. Option B incorrectly describes sacrificial anode protection, exploiting the common confusion between these two cathodic protection methods. Option C introduces the false concept of using AC current, playing on the 'current' terminology. Option D misrepresents the mechanism by suggesting potential matching, which is a cognitive bias from electrochemical series applications.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 808, "question": "What are the limitations of strain hardening as a strengthening method?", "answer": "Strain hardening does not fundamentally change the properties of the alloy. Under certain conditions, such as temperature increase, strain hardening may be lost due to the occurrence of recrystallization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释应变硬化的局限性，答案提供了详细的文字解释和论述，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目要求解释应变硬化的局限性，涉及对材料性能变化的理解和特定条件下（如温度升高）材料行为的分析。这需要将应变硬化的基本原理与实际应用中的限制条件关联起来，属于中等应用层次的知识。 | 难度: 在选择题中属于中等难度，需要理解应变硬化的基本原理及其局限性，并能关联温度变化对材料性能的影响。虽然题目涉及多个概念的综合分析，但在选择题型中，正确选项已经提供了明确的解释，减少了推理的复杂性。", "convertible": true, "correct_option": "Strain hardening does not fundamentally change the properties of the alloy. Under certain conditions, such as temperature increase, strain hardening may be lost due to the occurrence of recrystallization.", "choice_question": "What is a limitation of strain hardening as a strengthening method?", "conversion_reason": "The answer provided is a standard explanation of the limitations of strain hardening, which can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for a specific limitation.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Strain hardening increases dislocation density but does not alter the alloy's fundamental composition", "B": "Strain hardening significantly reduces electrical conductivity in all metallic alloys", "C": "Strain hardening causes permanent changes to the crystal structure type (e.g., FCC to BCC)", "D": "Strain hardening is ineffective for materials with high stacking fault energy" }, "correct_answer": "A", "explanation": "The correct answer A states the fundamental limitation that strain hardening only increases dislocation density without changing the alloy's composition. Option B is a cognitive bias trap, as while strain hardening may reduce conductivity, the effect varies by alloy system. Option C exploits a common misconception about crystal structure changes. Option D is a professional intuition trap, as high SFE materials can still be strain hardened, just with different characteristics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4764, "question": "The flexural strength and associated volume fraction porosity for two specimens of the same ceramic material are as follows: \begin{tabular}{ll} \\hline (\\sigma_{f_{S}}(\\mathbf{M P a})) & (\boldsymbol{P}) \\ \\hline 70 & 0.10 \\ 60 & 0.15 \\ \\hline \\end{tabular} (b) Compute the flexural strength for a 0.20 volume fraction porosity.", "answer": "the flexural strength for a 0.20 volume fraction porosity is 51.5 mpa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求根据给定的数据计算特定孔隙率下的弯曲强度，需要使用公式进行数值计算，答案也是具体的数值结果。 | 知识层次: 题目要求基于给定的数据应用基本公式进行计算，属于直接套用公式的简单应用。虽然需要理解公式的含义，但不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解并应用一个基本公式来计算弯曲强度，但解题步骤相对直接，仅涉及简单的代数运算和公式套用。与更复杂的需要多个公式组合或深入概念分析的题目相比，此题的难度较低。", "convertible": true, "correct_option": "51.5 MPa", "choice_question": "Given the flexural strength and associated volume fraction porosity for two specimens of the same ceramic material as follows: (σ_fs(MPa)) (P) 70 0.10 60 0.15, compute the flexural strength for a 0.20 volume fraction porosity.", "conversion_reason": "The calculation question has a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "51.5 MPa", "B": "53.2 MPa", "C": "49.8 MPa", "D": "55.0 MPa" }, "correct_answer": "A", "explanation": "正确答案A是通过正确应用孔隙率与强度关系的指数公式计算得出。干扰项B利用了线性外推的认知偏差，看似合理但不符合陶瓷材料的实际行为。干扰项C故意在计算中错误地使用了孔隙率的平方关系，利用了材料科学中常见的非线性关系混淆。干扰项D则基于对高强度陶瓷的直觉判断，忽略了孔隙率增加对强度的显著影响。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3312, "question": "What is the microstructural transformation of quenched steel during tempering at 200-300°C?", "answer": "Transformation of retained austenite", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释淬火钢在200-300°C回火时的微观结构转变，需要文字解释和论述，而不是选择或判断。答案也是以简短描述的形式给出。 | 知识层次: 题目要求解释淬火钢在200-300°C回火时的微观结构转变，涉及对回火过程中残余奥氏体转变的理解。这需要将热处理工艺参数与相变知识关联起来，属于中等应用层次。虽然不涉及复杂计算，但需要综合分析温度范围与相变类型的关系，比单纯记忆概念要求更高。 | 难度: 在选择题中属于中等难度，需要理解淬火钢在回火过程中的微观结构转变，特别是200-300°C温度范围内残余奥氏体的转变。这要求考生掌握相关概念并能进行综合分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Transformation of retained austenite", "choice_question": "What is the microstructural transformation of quenched steel during tempering at 200-300°C?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Transformation of retained austenite", "B": "Formation of pearlite colonies", "C": "Complete recrystallization of martensite", "D": "Precipitation of cementite needles" }, "correct_answer": "A", "explanation": "The correct answer is A because tempering at 200-300°C primarily causes the decomposition of retained austenite into bainite. Option B is incorrect as pearlite forms at higher temperatures (500-700°C). Option C is wrong because complete recrystallization requires temperatures above 400°C. Option D is a partial truth but cementite precipitation occurs predominantly above 300°C, making it a temperature-range confusion trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 340, "question": "What are the main characteristics of precipitation transformation?", "answer": "Precipitation occurs in alloys, involves compositional changes, and is primarily controlled by long-range diffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释沉淀转变的主要特征，答案提供了详细的文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对沉淀相变主要特征的基础概念记忆和理解，涉及合金中的沉淀现象、成分变化和扩散控制等基本原理，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项需要考生理解并描述沉淀转变的三个主要特征（发生在合金中、涉及成分变化、主要受长程扩散控制），这比单纯记忆定义（等级1）要求更高。然而，题目并未要求考生阐述复杂概念体系或进行多概念比较分析（等级3），因此属于概念解释和描述层次的难度等级2。", "convertible": true, "correct_option": "Precipitation occurs in alloys, involves compositional changes, and is primarily controlled by long-range diffusion.", "choice_question": "Which of the following describes the main characteristics of precipitation transformation?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Precipitation occurs in alloys, involves compositional changes, and is primarily controlled by long-range diffusion", "B": "Precipitation occurs in pure metals, involves structural changes, and is primarily controlled by short-range diffusion", "C": "Precipitation occurs in ceramics, involves phase separation without compositional changes, and is controlled by interfacial energy", "D": "Precipitation occurs in polymers, involves chain rearrangement, and is controlled by cooling rate" }, "correct_answer": "A", "explanation": "Correct answer A describes the three key characteristics of precipitation transformation in alloys: 1) occurs in alloy systems with solubility limits, 2) involves compositional changes as solute atoms cluster, and 3) is diffusion-controlled. Option B is wrong because precipitation doesn't occur in pure metals and requires long-range diffusion. Option C is misleading as it describes spinodal decomposition in ceramics rather than precipitation. Option D applies polymer crystallization concepts incorrectly to precipitation. Advanced AIs might confuse these similar but distinct phase transformation mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4490, "question": "Calculate the number-average molecular weight of a random nitrile rubber [poly(acrylonitrilebutadiene) copolymer] in which the fraction of butadiene repeat units is 0.30 ; assume that this concentration corresponds to a degree of polymerization of 2000 .", "answer": "the number-average molecular weight of the nitrile rubber copolymer is \\bar{m}_{n} = 106740, \\text{g/mol}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算数均分子量），并给出了具体的计算条件和公式应用（聚合度为2000，重复单元分数为0.30）。答案也是一个具体的数值结果（106740 g/mol），符合计算题的特征。 | 知识层次: 题目需要多步计算和概念关联，包括理解共聚物的组成、重复单元分子量的计算以及数均分子量的综合计算。虽然涉及基本公式应用，但需要综合分析共聚物的组成和聚合度的影响，思维过程有一定深度要求。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求计算数均分子量，涉及重复单元分数、聚合度等概念的综合运用，并需要进行多步计算。虽然题目提供了明确的参数和公式，但需要考生具备一定的材料科学基础知识和计算能力，属于中等应用层次的问题。", "convertible": true, "correct_option": "106740 g/mol", "choice_question": "Calculate the number-average molecular weight of a random nitrile rubber [poly(acrylonitrile-butadiene) copolymer] in which the fraction of butadiene repeat units is 0.30; assume that this concentration corresponds to a degree of polymerization of 2000. The number-average molecular weight is:", "conversion_reason": "The calculation problem has a specific numerical answer, which can be presented as a correct option in a multiple-choice format. The question can be rephrased to fit the structure of a multiple-choice question by asking for the specific value.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "106740 g/mol", "B": "89260 g/mol", "C": "120000 g/mol", "D": "95300 g/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (106740 g/mol) calculated by considering the weighted average of acrylonitrile (53.06 g/mol) and butadiene (54.09 g/mol) repeat units multiplied by the degree of polymerization (2000). Option B is incorrect because it reverses the weight fractions. Option C is a common mistake from ignoring the butadiene fraction. Option D results from incorrect unit conversion between repeat units.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3972, "question": "As a metal is strain hardened, its ductility(a) increases(b) decreases", "answer": "As a metal is strain hardened, its ductility decreases.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(a)和(b)中选择正确答案，符合选择题的特征 | 知识层次: 题目考查金属应变硬化与延展性关系的基本概念记忆和理解 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需识别金属应变硬化后延展性的变化趋势。选项直接对应教材定义，无需理解或辨析过程，属于最简单的概念识别层级。", "convertible": true, "correct_option": "decreases", "choice_question": "As a metal is strain hardened, its ductility", "conversion_reason": "The original question is already in a multiple-choice format with two options (a) increases and (b) decreases. The answer provided clearly indicates the correct option, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "increases due to dislocation annihilation during dynamic recovery", "B": "decreases", "C": "remains constant as strain hardening only affects yield strength", "D": "first increases then decreases as dislocations rearrange into low-angle grain boundaries" }, "correct_answer": "B", "explanation": "The correct answer is B because strain hardening increases dislocation density, which impedes further dislocation motion and reduces ductility. Option A is a cognitive bias trap suggesting recovery mechanisms dominate. Option C exploits confusion between yield strength and ductility. Option D is a multi-level trap combining partial truths about dislocation rearrangement with incorrect ductility behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 549, "question": "Aging", "answer": "Aging: The subsequent process of solute atom precipitation from a supersaturated solid solution at room temperature or above.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Aging\"这一概念进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征 | 知识层次: 题目考查对\"Aging\"这一基础概念的定义记忆和理解，属于材料科学中的基本原理和定义性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"Aging\"的基本定义，属于最基础的概念记忆层次。题目直接给出了明确的定义描述，无需进行概念解释或复杂分析，符合等级1\"基本定义简答\"的标准。选择题型中此类题目通常作为基础题出现，主要测试学生对专业术语的识记能力。", "convertible": true, "correct_option": "The subsequent process of solute atom precipitation from a supersaturated solid solution at room temperature or above.", "choice_question": "Which of the following best defines aging?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The subsequent process of solute atom precipitation from a supersaturated solid solution at room temperature or above", "B": "The gradual loss of ductility in metallic alloys due to prolonged exposure to elevated temperatures", "C": "The time-dependent relaxation of residual stresses in polymer composites under constant strain", "D": "The spontaneous decomposition of metastable phases into equilibrium structures through diffusionless transformation" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines aging in materials science as the precipitation process from supersaturated solutions. Option B describes thermal embrittlement, not aging. Option C refers to stress relaxation in polymers, a different phenomenon. Option D describes martensitic transformation, which is diffusionless and unrelated to aging. The distractors exploit common misconceptions by presenting related but distinct material processes that share some characteristics with aging but differ fundamentally in mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2883, "question": "In a eutectic reaction of the Mg-Ni system, let C1 be the hypoeutectic alloy and C2 be the hypereutectic alloy. The mass fractions of the proeutectic phases in these two alloys are equal. Find the relationship between C1 and C2.", "answer": "According to the lever rule, the mass fractions of the proeutectic phases are: α_pro=(23.5-C1)/23.5 β_pro=(C2-23.5)/(54.6-23.5) Given that α_pro=β_pro, combining the above equations yields: C2=54.6-1.323C1", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用（杠杆定律）来求解C1和C2之间的关系，答案给出了具体的计算过程和结果。 | 知识层次: 题目需要应用杠杆定律进行多步计算，并建立两个合金成分之间的关系。虽然计算过程不复杂，但需要理解共晶反应和杠杆定律的应用，并进行综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解共晶反应、杠杆定律等概念，并进行多步计算和综合分析。题目要求建立两个合金成分之间的关系，涉及多个变量的计算和方程组合，但选项提供了明确的解题路径，降低了部分难度。", "convertible": true, "correct_option": "C2=54.6-1.323C1", "choice_question": "In a eutectic reaction of the Mg-Ni system, let C1 be the hypoeutectic alloy and C2 be the hypereutectic alloy. The mass fractions of the proeutectic phases in these two alloys are equal. The relationship between C1 and C2 is:", "conversion_reason": "The answer is a specific mathematical relationship, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "C2=54.6-1.323C1", "B": "C2=54.6+1.323C1", "C": "C2=1.323C1-54.6", "D": "C2=1.323C1+54.6" }, "correct_answer": "A", "explanation": "正确答案A基于Mg-Ni系统相图的精确计算，考虑了共晶点位置和杠杆定律的应用。干扰项B通过符号反转制造认知偏差，利用常见计算错误模式。干扰项C和D通过系数与常数的位置互换，针对不熟悉相图定量分析的学习者。所有干扰项都保持数值相似性，但只有A正确反映了共晶反应中两相质量分数相等的条件。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1849, "question": "Sintering", "answer": "Sintering: A process in which one or more solid powders are formed and then heated to a certain temperature, causing them to shrink and become a dense, hard sintered body below the melting point temperature. Alternatively: Due to the mutual attraction of molecules (or atoms) in solids, heating causes the powder particles to bond, and through material migration and diffusion, the powder gains strength, leading to densification and recrystallization—this process is called sintering.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Sintering\"这一概念进行文字解释和论述，答案提供了详细的定义和过程描述，符合简答题的特征。 | 知识层次: 题目考查烧结过程的基本定义和原理，属于基础概念的记忆和理解，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解和记忆烧结的基本定义和过程，虽然涉及一定的细节描述（如粉末颗粒的粘结、材料迁移和扩散等），但整体上仍属于对单一概念的明确解释，不需要进行复杂的概念体系阐述或多概念比较分析。", "convertible": true, "correct_option": "Sintering: A process in which one or more solid powders are formed and then heated to a certain temperature, causing them to shrink and become a dense, hard sintered body below the melting point temperature. Alternatively: Due to the mutual attraction of molecules (or atoms) in solids, heating causes the powder particles to bond, and through material migration and diffusion, the powder gains strength, leading to densification and recrystallization—this process is called sintering.", "choice_question": "下列关于Sintering的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Sintering occurs through surface diffusion and grain boundary migration at temperatures below melting point", "B": "Sintering requires complete melting of powder particles to achieve full densification", "C": "Hot isostatic pressing (HIP) is a necessary post-processing step for all sintering operations", "D": "The driving force for sintering comes primarily from external pressure rather than surface energy reduction" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual mass transport mechanisms in sintering. Option B is wrong but exploits the common misconception that melting is required for bonding. Option C uses a real process (HIP) but falsely generalizes its necessity. Option D reverses the true driving force (surface energy reduction) with a plausible-sounding alternative.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 754, "question": "After the interaction between water and clay, what can be found around the clay colloidal particles as the distance increases: (10) what?", "answer": "Free water", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用简短的文字回答具体问题，答案形式为自由文本而非选择或判断 | 知识层次: 题目考查的是对粘土胶体颗粒与水相互作用后周围水分分布的基本概念记忆，属于基础概念的理解和记忆层次，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即水与黏土相互作用后黏土胶体颗粒周围随着距离增加会出现什么（自由水）。题目仅要求识别定义性知识，无需解释或分析，属于最基础的定义简答级别。", "convertible": true, "correct_option": "Free water", "choice_question": "After the interaction between water and clay, what can be found around the clay colloidal particles as the distance increases?", "conversion_reason": "The answer is a standard term (Free water), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Free water", "B": "Bound water with reduced mobility", "C": "Double layer of counterions", "D": "Hydrated silicate layers" }, "correct_answer": "A", "explanation": "The correct answer is A because as distance increases from clay particles, water molecules transition from tightly bound to free water. B is incorrect as it describes the immediate hydration shell, not distant regions. C is a trap for those confusing the electrical double layer theory with actual water distribution. D exploits the common misconception that silicate layers remain hydrated at all distances.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4767, "question": "The following table gives a number of yield strength values (in MPa) that were measured on the same aluminum alloy. Compute average and standard deviation yield strength values.\n\\begin{tabular}{rrr}\n274.3 & 277.1 & 263.8 \\\\\n267.5 & 258.6 & 271.2 \\\\\n255.4 & 266.9 & 257.6 \\\\\n270.8 & 260.1 & 264.3 \\\\\n261.7 & 279.4 & 260.5\n\\end{tabular}", "answer": "the average yield strength is 265.9 \\text{ mpa}. the standard deviation of the yield strength is 7.34 \\text{ mpa}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求计算平均屈服强度和标准偏差，需要数值计算和公式应用 | 知识层次: 题目主要涉及基本的统计计算（平均值和标准差），属于直接套用公式的应用层面，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单应用层次，主要考察基本公式应用和简单计算能力。虽然需要计算平均值和标准差，但题目已经给出了所有数据，且计算步骤相对直接，只需套用公式即可得出结果。不需要复杂的分析或组合多个公式，因此属于等级2难度。", "convertible": true, "correct_option": "the average yield strength is 265.9 mpa. the standard deviation of the yield strength is 7.34 mpa.", "choice_question": "The following table gives a number of yield strength values (in MPa) that were measured on the same aluminum alloy. What are the average and standard deviation yield strength values?", "conversion_reason": "The answer is a specific numerical result, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "265.9 MPa ± 7.34 MPa", "B": "267.2 MPa ± 6.89 MPa", "C": "263.5 MPa ± 8.12 MPa", "D": "269.1 MPa ± 5.97 MPa" }, "correct_answer": "A", "explanation": "The correct answer is A because it precisely matches the calculated average (265.9 MPa) and standard deviation (7.34 MPa) from the given data. Option B uses values close to the correct average but with a reduced standard deviation, exploiting the tendency to underestimate dispersion. Option C presents a lower average with an inflated standard deviation, targeting the misconception that outliers should significantly shift both parameters. Option D shows a higher average with an artificially low standard deviation, appealing to the intuition that stronger materials should have tighter property distributions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3665, "question": "Calculate the length of the Burgers vector in FCC silver", "answer": "b = 2.889 Å", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算FCC银中Burgers矢量的长度），答案是一个具体的数值结果（2.889 Å），需要使用材料科学中的相关公式和计算方法。 | 知识层次: 题目要求计算FCC银的Burgers矢量长度，这需要应用基本的晶体学公式和已知的晶格常数进行简单计算。虽然需要理解Burgers矢量的概念，但计算过程直接且不涉及多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需直接应用FCC晶体结构中Burgers矢量的基本公式（b = a√2/2），并进行简单的数值计算。题目明确给出了所有必要参数（FCC银的晶格常数a=4.09Å），解题步骤单一且无需复杂推导，完全符合等级1\"单一公式直接计算\"的标准。", "convertible": true, "correct_option": "b = 2.889 Å", "choice_question": "What is the length of the Burgers vector in FCC silver?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.889 Å (correct FCC calculation)", "B": "2.048 Å (BCC calculation with Ag lattice parameter)", "C": "4.085 Å (direct use of Ag lattice constant)", "D": "1.444 Å (half of correct FCC value)" }, "correct_answer": "A", "explanation": "The correct answer A uses the proper FCC Burgers vector formula b=a√2/2 with Ag's lattice parameter a=4.085 Å. Option B traps those confusing FCC/BCC Burgers vector calculations. Option C exploits surface-level knowledge by directly using the lattice constant. Option D preys on intuition to halve values without proper basis.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3385, "question": "The large screwdriver requires the shank to be fine pearlite and the tip to be tempered martensite, with only one external heat source. How should it be processed?", "answer": "Overall normalizing, local quenching + low-temperature tempering.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释如何通过热处理工艺实现螺丝刀不同部位的组织要求，答案提供了具体的处理步骤，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求综合运用热处理知识（正火、局部淬火+低温回火）来解决实际问题，需要理解不同热处理工艺对材料微观组织的影响，并进行推理分析以实现特定部位的不同性能要求。这涉及多步骤的工艺设计和综合分析能力，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Overall normalizing, local quenching + low-temperature tempering", "choice_question": "The large screwdriver requires the shank to be fine pearlite and the tip to be tempered martensite, with only one external heat source. How should it be processed?", "conversion_reason": "The answer is a standard process term, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Overall normalizing, local quenching + low-temperature tempering", "B": "Full austenitizing followed by differential cooling rates", "C": "Localized induction hardening of the tip only", "D": "Through-hardening followed by selective tempering of the shank" }, "correct_answer": "A", "explanation": "The correct answer is A because normalizing produces fine pearlite in the shank, while local quenching of the tip forms martensite which is then tempered. Option B is a cognitive bias trap - differential cooling sounds plausible but cannot guarantee the required microstructure combination with a single heat source. Option C exploits professional intuition by suggesting a common surface hardening method, but fails to address the shank requirement. Option D is a multi-level verification trap - through-hardening would make the entire tool martensitic, making selective tempering impossible to achieve pearlite in the shank.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4322, "question": "What is the principal difference between congruent and incongruent phase transformations?", "answer": "The principal difference between congruent and incongruent phase transformations is that for congruent no compositional changes occur with any of the phases that are involved in the transformation. For incongruent there will be compositional alterations of the phases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述两种相变的主要区别，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对相变类型的基本概念记忆和理解，即区分共格和非共格相变的主要特征，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（定义和分类），但需要考生理解并区分两个相关但不同的概念（congruent和incongruent相变）。正确选项要求考生不仅记住定义，还需要能够解释两种相变的关键区别（成分变化与否）。这比单纯记忆单个定义（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "The principal difference between congruent and incongruent phase transformations is that for congruent no compositional changes occur with any of the phases that are involved in the transformation. For incongruent there will be compositional alterations of the phases.", "choice_question": "What is the principal difference between congruent and incongruent phase transformations?", "conversion_reason": "The answer is a standard explanation of the difference between congruent and incongruent phase transformations, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Congruent transformations preserve crystal symmetry while incongruent alter it", "B": "Congruent transformations occur isothermally while incongruent require temperature gradients", "C": "Congruent transformations maintain phase composition while incongruent involve composition changes", "D": "Congruent transformations are reversible while incongruent are irreversible" }, "correct_answer": "C", "explanation": "Correct answer C directly addresses the compositional aspect that defines the fundamental difference. Distractors exploit common misconceptions: A falsely links to symmetry changes (a separate phenomenon), B misattributes kinetic conditions, and D incorrectly associates with reversibility (which depends on thermodynamics not transformation type). Advanced AIs may overcomplicate by considering secondary characteristics rather than the core compositional criterion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2606, "question": "In the periodic table, what are the common characteristics of atomic structures for elements in the same main group?", "answer": "Elements in the same main group have the same number of outer electrons.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释元素在同一主族中的共同特征，答案需要文字解释和论述，而非选择、判断或计算。 | 知识层次: 题目考查对元素周期表中主族元素原子结构共同特征的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅考察对元素周期表主族元素外层电子数相同这一基础定义的记忆，无需解释或分析，属于最基本的概念记忆题。", "convertible": true, "correct_option": "Elements in the same main group have the same number of outer electrons.", "choice_question": "What are the common characteristics of atomic structures for elements in the same main group in the periodic table?", "conversion_reason": "The answer is a standard concept in chemistry, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Elements in the same main group have the same number of outer electrons", "B": "Elements in the same main group have identical atomic radii", "C": "Elements in the same main group exhibit the same crystal structure", "D": "Elements in the same main group have equal electronegativity values" }, "correct_answer": "A", "explanation": "The correct answer is A because elements in the same main group share the same number of valence electrons, which determines their chemical properties. Option B is incorrect because atomic radii increase down a group due to additional electron shells. Option C is a trap as crystal structures vary significantly even within groups (e.g., carbon vs silicon). Option D exploits the misconception that electronegativity is constant within groups, when it actually decreases down a group due to increased atomic size.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 427, "question": "6. Common methods for strengthening metal materials include: (13)", "answer": "Grain refinement strengthening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举金属材料强化的常见方法，需要简要回答具体强化方式（晶粒细化强化），属于需要文字解释的简答题类型。 | 知识层次: 题目考查对金属材料强化方法的基础概念记忆，属于基本原理等记忆性知识 | 难度: 在选择题型中，该题目仅考察对金属材料强化方法中最基础概念的识别能力（晶粒细化强化），属于单一知识点的基础记忆层面，不需要解释或分析过程，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Grain refinement strengthening", "choice_question": "Which of the following is a common method for strengthening metal materials?", "conversion_reason": "The answer is a standard term related to the question topic, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain refinement strengthening", "B": "Increasing elastic modulus", "C": "Reducing dislocation density", "D": "Applying uniform tensile stress" }, "correct_answer": "A", "explanation": "Grain refinement strengthening (A) is correct as it increases grain boundaries which impede dislocation motion. Increasing elastic modulus (B) exploits confusion between stiffness and strength - modulus is intrinsic. Reducing dislocation density (C) is a reverse trap since dislocations actually enable plasticity. Applying uniform tensile stress (D) mimics common testing conditions but doesn't strengthen the material itself.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1098, "question": "The Burgers vectors of edge dislocations and screw dislocations are perpendicular and parallel to the direction vectors of the dislocation lines, respectively, so a curved dislocation line has different properties.", "answer": "The Burgers vectors of edge dislocations and screw dislocations are perpendicular and parallel to the direction vectors of the dislocation lines, respectively. For a curved dislocation line, its Burgers vector remains constant, but the properties vary along the line as the geometric relationship between the direction vector of the dislocation line and the Burgers vector changes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对位错的性质进行文字解释和论述，答案提供了详细的描述和分析，符合简答题的特征。 | 知识层次: 题目涉及位错的基本概念（刃位错和螺位错的柏氏矢量方向）以及它们在曲线位错线上的变化，需要理解并应用这些概念来分析位错性质的变化。虽然知识点本身属于基础概念，但题目要求对不同位错类型在曲线位错线上的性质变化进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解位错的基本概念（刃位错和螺位错的柏氏矢量方向与位错线方向的关系），并能综合分析弯曲位错线上不同位置的性质变化。题目涉及多个概念的关联和比较，但不需要进行复杂的多角度分析或深度关联性分析。", "convertible": true, "correct_option": "The Burgers vectors of edge dislocations and screw dislocations are perpendicular and parallel to the direction vectors of the dislocation lines, respectively. For a curved dislocation line, its Burgers vector remains constant, but the properties vary along the line as the geometric relationship between the direction vector of the dislocation line and the Burgers vector changes.", "choice_question": "Which of the following statements correctly describes the Burgers vectors of edge dislocations and screw dislocations, and the properties of a curved dislocation line?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question because the answer is a specific and well-defined statement about the properties of dislocations. The question can be rephrased to ask for the correct description among possible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Burgers vectors of edge dislocations are perpendicular to the dislocation line direction, while for screw dislocations they are parallel. A curved dislocation line has constant Burgers vector but varying character along its length.", "B": "Both edge and screw dislocations have Burgers vectors parallel to their line directions, but edge dislocations additionally require perpendicular slip planes. Curved dislocations maintain constant Burgers vector magnitude but may change direction.", "C": "Edge dislocations have Burgers vectors parallel to the line direction while screw dislocations have perpendicular Burgers vectors. Curved dislocations exhibit continuous transition between these two pure types.", "D": "The Burgers vector orientation is irrelevant for dislocation classification. All curved dislocations naturally maintain pure edge character throughout their length due to strain field symmetry." }, "correct_answer": "A", "explanation": "Option A is correct as it accurately describes the fundamental relationship between Burgers vectors and dislocation line directions for both edge and screw dislocations, and correctly states that a curved dislocation's Burgers vector remains constant while its character varies. Option B is incorrect because it falsely claims both dislocation types have parallel Burgers vectors. Option C reverses the Burgers vector relationships for edge and screw dislocations. Option D is completely wrong by dismissing the importance of Burgers vector orientation and making false claims about curved dislocations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3322, "question": "What is the hardenability of steel?", "answer": "The hardenability of steel refers to the ability of steel to obtain martensite during quenching.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释\"hardenability of steel\"的定义，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对钢的淬透性这一基本概念的定义和记忆，属于基础概念的理解和表述。 | 难度: 在选择题型中，该题目仅考察对\"钢的淬透性\"这一基础定义的记忆，属于最基本的概念性知识。题目仅要求识别正确选项中的定义描述，不需要任何解释、分析或比较过程，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The hardenability of steel refers to the ability of steel to obtain martensite during quenching.", "choice_question": "What does the hardenability of steel refer to?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The ability of steel to obtain martensite during quenching", "B": "The maximum hardness achievable in steel through heat treatment", "C": "The resistance of steel to deformation under applied stress", "D": "The depth to which steel can be hardened by rapid cooling" }, "correct_answer": "A", "explanation": "The correct answer is A because hardenability specifically refers to the steel's capacity to form martensite during quenching, not the maximum hardness (B) which depends on carbon content. Option C describes mechanical strength, not hardenability. Option D is a common misconception - while related to hardenability, it's actually a measurable consequence (Jominy test) rather than the definition itself.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1099, "question": "Calculate the planar density of the (100) plane in a face-centered cubic crystal, given the atomic radius r=(√2/4)a", "answer": "For the (100) plane of a face-centered cubic crystal, there are 2 atoms. The planar density is calculated as: 2×π(√2/4 a)^2 / a^2 = 2π×1/8 = π/4 = 0.785", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程中涉及到了平面密度的计算和原子半径的代入，最终给出了具体的数值结果。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即计算面心立方晶体(100)面的平面密度。虽然需要理解晶体结构和原子半径的关系，但整体上是一个直接套用公式的计算过程，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用平面密度的计算公式，但题目已经给出了原子半径与晶格常数的关系，且计算步骤较为直接，仅需套用公式并进行简单代数运算即可得出结果。相较于需要多个公式组合或复杂分析的题目，此题的解题步骤较为简单，属于选择题型中的中等偏低难度。", "convertible": true, "correct_option": "0.785", "choice_question": "What is the planar density of the (100) plane in a face-centered cubic crystal, given the atomic radius r=(√2/4)a?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.785", "B": "0.555", "C": "0.866", "D": "0.707" }, "correct_answer": "A", "explanation": "The correct answer is A (0.785) because the planar density is calculated by dividing the number of atoms in the (100) plane (2 atoms) by the area of the plane (a²), where a is the lattice parameter. Given r=(√2/4)a, the area becomes 8r², resulting in 2/(8r²) = 0.785. Option B (0.555) is a common error from incorrectly calculating the area as 4r². Option C (0.866) exploits the intuition of close-packed planes but is incorrect for the (100) plane. Option D (0.707) is derived from a miscalculation using √2/2 instead of the correct planar density formula.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1441, "question": "A metal with finer grains exhibits this phenomenon compared to the same metal with coarser grains, which is called (18) strengthening", "answer": "(18) fine grain", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（fine grain）来回答问题，属于需要简短文字回答的类型，而不是从多个选项中选择或进行判断、计算。 | 知识层次: 题目考查的是对金属材料中晶粒细化强化现象的基本概念记忆，即\"fine grain strengthening\"这一术语的识别和填写，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即\"细晶强化\"这一术语的定义。学生只需识别并选择\"fine grain\"这个正确选项即可，无需进行概念解释或复杂分析。这属于最基本的知识点回忆型题目，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "fine grain", "choice_question": "A metal with finer grains exhibits this phenomenon compared to the same metal with coarser grains, which is called:", "conversion_reason": "The answer is a standard term (fine grain) that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hall-Petch strengthening", "B": "Orowan bowing effect", "C": "Peierls-Nabarro stress", "D": "Cottrell atmosphere" }, "correct_answer": "A", "explanation": "The correct answer is A because the Hall-Petch relationship specifically describes the phenomenon where finer grain sizes lead to increased yield strength in polycrystalline materials. Option B (Orowan bowing) is a dislocation bypass mechanism for precipitate strengthening, creating confusion between grain boundary and precipitate effects. Option C (Peierls-Nabarro) relates to intrinsic lattice friction stress, exploiting the AI's potential to confuse different types of strengthening mechanisms. Option D (Cottrell atmosphere) involves solute-dislocation interactions, designed to trap AI models that might overgeneralize strengthening mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3993, "question": "How does deformation by drawing of a semicrystalline polymer affect its tensile strength?(a) Increases(b) Decreases", "answer": "Deformation by drawing increases the tensile strength of a semicrystalline polymer. This effect is due to the highly oriented chain structure that is produced by drawing, which gives rise to higher interchain secondary bonding forces.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从给定的选项(a)和(b)中选择正确答案 | 知识层次: 题目需要理解半结晶聚合物在拉伸变形过程中的微观结构变化（链取向）及其对宏观性能（拉伸强度）的影响机制，涉及概念关联和综合分析能力 | 难度: 在选择题中属于较高难度，需要理解半晶态聚合物在拉伸变形过程中的微观结构变化（如分子链取向）及其对宏观力学性能（拉伸强度）的影响机制。这涉及材料科学中的晶体学原理、聚合物加工-结构-性能关系等中等应用层次的知识，并要求考生能够综合分析变形工艺与性能提升之间的因果关系。虽然题目形式为二选一，但正确选项的解释涉及多步逻辑推导和概念关联，超出了基础记忆题的范畴。", "convertible": true, "correct_option": "Increases", "choice_question": "How does deformation by drawing of a semicrystalline polymer affect its tensile strength?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly indicates the correct choice.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases due to molecular chain alignment and strain-induced crystallization", "B": "Decreases because the drawing process introduces microvoids and defects", "C": "Remains unchanged as the crystalline domains prevent structural reorganization", "D": "Initially decreases then increases due to competing mechanisms of chain slippage and orientation" }, "correct_answer": "A", "explanation": "The correct answer is A because drawing aligns polymer chains in the direction of stress and promotes strain-induced crystallization, both of which enhance tensile strength. Option B exploits the common misconception that any deformation process necessarily introduces weakening defects. Option C targets the flawed intuition that crystalline domains are completely rigid. Option D creates a complex temporal sequence that seems plausible but doesn't reflect the dominant strengthening mechanism in semicrystalline polymers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4354, "question": "What is the second stage involved in the formation of particles of a new phase? Briefly describe it.", "answer": "The second stage is growth. The growth stage is simply the increase in size of the new phase particles.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述新相粒子形成的第二阶段，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对相变过程中第二阶段（growth）的基本概念记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但要求考生不仅知道第二阶段的名称（生长），还需要简要描述该阶段的特点（新相颗粒尺寸的增加）。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。", "convertible": true, "correct_option": "The second stage is growth. The growth stage is simply the increase in size of the new phase particles.", "choice_question": "What is the second stage involved in the formation of particles of a new phase?", "conversion_reason": "The answer is a standard term or concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Growth - the increase in size of the new phase particles", "B": "Nucleation - the formation of stable clusters of the new phase", "C": "Coarsening - the competitive growth where larger particles grow at the expense of smaller ones", "D": "Diffusion - the atomic transport process enabling phase transformation" }, "correct_answer": "A", "explanation": "The correct answer is A because the second stage in new phase formation is growth, following initial nucleation. Option B is the first stage (nucleation) which is a common temporal confusion. Option C describes a later stage (Ostwald ripening) that occurs after significant growth. Option D is a supporting mechanism throughout the process but not a distinct stage, exploiting the tendency to select fundamental processes over stage classification.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1553, "question": "7. Up-hill diffusion", "answer": "The diffusion of atoms from a low concentration to a high concentration region, driven by the chemical potential gradient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Up-hill diffusion\"进行文字解释和论述，答案是一个定义性的描述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即\"Up-hill diffusion\"的定义和驱动机制，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆\"Up-hill diffusion\"的定义及其驱动机制（化学势梯度），但不需要进行多个概念的比较分析或复杂推理。虽然涉及专业术语\"chemical potential gradient\"，但整体仍属于基础概念的记忆和理解范畴，比简单定义题稍难但未达到复杂概念体系阐述的难度。", "convertible": true, "correct_option": "The diffusion of atoms from a low concentration to a high concentration region, driven by the chemical potential gradient.", "choice_question": "Which of the following best describes up-hill diffusion?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The diffusion of atoms from a low concentration to a high concentration region, driven by the chemical potential gradient", "B": "The accelerated diffusion observed in nanomaterials due to high surface-to-volume ratio", "C": "The temperature-dependent reversal of diffusion direction in binary alloys", "D": "The anomalous diffusion behavior caused by vacancy clustering in irradiated materials" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines up-hill diffusion as counter-intuitive mass transport against concentration gradient but following chemical potential gradient. Option B exploits the common confusion between size effects and thermodynamic driving forces. Option C creates a plausible-sounding temperature-dependent phenomenon that doesn't exist. Option D uses real irradiation effects but misapplies them to diffusion mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2465, "question": "For heterogeneous nucleation at grain boundaries (double spherical cap shape, with all interfaces being incoherent), what is the critical nucleus formation energy ΔGb*? Given the contact angle θ=50°, nucleation driving force ΔG1=5×10^8 J/m^3, and incoherent interface energy γin=0.5 J/m^2.", "answer": "The calculation process for the critical nucleus formation energy ΔGb* is as follows: First, calculate the shape factor f(θ) = 0.5×(2-3cos50°+cos^3 50°) = 0.3125. The critical nucleus radius for homogeneous nucleation (spherical shape) rin* = 2γin/ΔG1 = 2×0.5/(5×10^8) m = 2×10^-9 m. The critical nucleus formation energy for homogeneous nucleation ΔGin* = (16π/3)(γin^3)/(ΔG1^2) = (16π/3)(0.5^3)/(5×10^8)^2 J = 8.37×10^-18 J. The critical nucleus formation energy for heterogeneous nucleation ΔGb* = f(θ)ΔGin* = 8.37×10^-18×0.3125 J = 2.615×10^-18 J.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解临界核形成能量ΔGb*，答案中包含了具体的计算步骤和数值结果。 | 知识层次: 题目涉及多步计算和概念关联，需要理解异质成核的形状因子、临界核形成能的计算方法，并综合应用相关公式进行计算。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如异质形核、临界核形成能、接触角等）并进行多步骤计算（包括形状因子计算、临界核半径计算、均质形核能计算等）。虽然题目提供了具体数值和公式，但解题过程涉及多个变量和步骤的综合运用，对学生的计算能力和概念关联能力要求较高。", "convertible": true, "correct_option": "2.615×10^-18 J", "choice_question": "For heterogeneous nucleation at grain boundaries (double spherical cap shape, with all interfaces being incoherent), what is the critical nucleus formation energy ΔGb*? Given the contact angle θ=50°, nucleation driving force ΔG1=5×10^8 J/m^3, and incoherent interface energy γin=0.5 J/m^2.", "conversion_reason": "The answer is a specific numerical value derived from a calculation, making it suitable for conversion into a multiple-choice question format where the correct option is the calculated result.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.615×10^-18 J", "B": "1.307×10^-18 J", "C": "5.230×10^-18 J", "D": "3.922×10^-18 J" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the double spherical cap model for grain boundary nucleation, considering the geometric factor f(θ) = (2 + cosθ)(1 - cosθ)^2/4. The interference options are designed as follows: B is half the correct value (tempting for those who forget the geometric factor), C is exactly double (common error in volume vs energy calculations), and D is 1.5 times the correct value (tempting for those who misapply the incoherent interface energy factor). All options maintain correct units to avoid obvious detection.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 646, "question": "Write the expression for the unsteady-state diffusion equation", "answer": "The expression for the unsteady-state diffusion equation is: ∂C/∂t = ∂(D(∂c/∂x))/∂x. If the diffusion coefficient D does not vary with concentration, it can be simplified to ∂C/∂t = D(∂²c/∂x²).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求写出非稳态扩散方程的表达式，并给出了详细的解释和可能的简化形式，这属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对非稳态扩散方程表达式的基本记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目要求考生回忆并写出非稳态扩散方程的基本表达式，并理解在扩散系数D不随浓度变化时的简化形式。这属于概念解释和描述的难度级别，需要考生对扩散方程有基本的理解和记忆，但不需要进行复杂的推导或分析。", "convertible": true, "correct_option": "∂C/∂t = D(∂²c/∂x²)", "choice_question": "Which of the following is the correct expression for the unsteady-state diffusion equation when the diffusion coefficient D does not vary with concentration?", "conversion_reason": "The answer is a standard and specific mathematical expression, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "∂C/∂t = D(∂²C/∂x²)", "B": "∂C/∂x = D(∂²C/∂t²)", "C": "∂²C/∂t² = D(∂²C/∂x²)", "D": "∂C/∂t = D(∂C/∂x)" }, "correct_answer": "A", "explanation": "The correct answer is A because it properly represents Fick's second law for unsteady-state diffusion with constant D. Option B reverses the spatial and temporal derivatives, a common mistake when confusing diffusion wave equations. Option C incorrectly introduces a second-order time derivative, mimicking wave equation forms seen in other physics domains. Option D represents a first-order approximation error, tempting those who recall concentration gradient terms from Fick's first law but fail to account for the second derivative needed for non-steady state conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1252, "question": "Under what conditions is the first law of diffusion only applicable?", "answer": "Steady state", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释在什么条件下第一扩散定律适用，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对扩散第一定律适用条件的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅考察对扩散第一定律适用条件的基础定义记忆，属于最基础的概念性知识。正确选项\"Steady state\"是直接来自定义的关键词，不需要任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Steady state", "choice_question": "Under what conditions is the first law of diffusion only applicable?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Steady state", "B": "When the concentration gradient is linear", "C": "For ideal solutions only", "D": "At constant temperature" }, "correct_answer": "A", "explanation": "The first law of diffusion (Fick's first law) is strictly applicable only under steady-state conditions where the concentration profile doesn't change with time. Option B is a strong distractor because a linear gradient often occurs in steady state, but it's not the defining condition. Option C exploits the common confusion between ideal solutions and diffusion mechanisms. Option D is a temperature-dependent trap, as diffusion coefficients are temperature-dependent but the law itself applies regardless of temperature constancy.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4036, "question": "Conductivity in a metal is almost always reduced by the introduction of defects into the lattice.\nThe factor primarily affected by defects is:\n[a] free electron concentration\n[b] electron charge\n[c] electron mobility\n[d] electron spin", "answer": "[c] electron mobility", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对金属导电性影响因素的基础概念记忆，特别是缺陷对电子迁移率的影响，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解金属导电性的基本原理，并能够辨析不同因素（如自由电子浓度、电子电荷、电子迁移率和电子自旋）对导电性的影响。正确选项（电子迁移率）需要考生对缺陷如何影响电子运动有基本的理解，而不仅仅是简单的记忆。因此，该题目属于概念理解和简单辨析的难度等级。", "convertible": true, "correct_option": "electron mobility", "choice_question": "Conductivity in a metal is almost always reduced by the introduction of defects into the lattice. The factor primarily affected by defects is:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dislocation density threshold for dynamic recovery in aluminum at 300K", "B": "The critical resolved shear stress for slip system activation in pure copper", "C": "The Peierls-Nabarro stress required for dislocation motion in tungsten", "D": "The stacking fault energy value for austenitic stainless steel" }, "correct_answer": "C", "explanation": "The Peierls-Nabarro stress is the fundamental measure of lattice resistance to dislocation motion in BCC metals like tungsten, making it the most direct indicator of intrinsic lattice strength. Option A exploits the common confusion between static and dynamic dislocation behaviors, while B targets the misconception that CRSS represents intrinsic rather than extrinsic resistance. Option D leverages the intuitive but incorrect association between stacking fault energy and overall strength.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2592, "question": "A screw dislocation with $b=a/2$ [10] moves on the (111) plane. If it encounters an obstacle during motion and undergoes cross-slip, please identify the cross-slip system.", "answer": "∵ All planes containing the direction of the screw dislocation are slip planes, ∴ For the FCC crystal slip plane (111), only (111) and (11 ) contain $I=b={\\\\sf a}/2$ [10]. ∴ If cross-slip occurs, it must be from the (111) plane to the (11 ) plane.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来识别交叉滑移系统，答案提供了详细的推导过程和结论，属于需要文字解释的简答题类型。 | 知识层次: 题目需要理解螺位错的基本性质及其在FCC晶体中的滑移系统，并能够分析在不同滑移面之间的交叉滑移过程。这涉及到多个概念的关联和综合分析，但不需要过于复杂的推理或创新应用。 | 难度: 在选择题型中，该题目属于较高难度，需要考生具备以下能力：", "convertible": true, "correct_option": "从(111)平面到(11 )平面", "choice_question": "A screw dislocation with $b=a/2$ [10] moves on the (111) plane. If it encounters an obstacle during motion and undergoes cross-slip, the cross-slip system is:", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。原答案明确指出了交叉滑移系统是从(111)平面到(11 )平面，因此可以提取为正确选项。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "From (111) to (11 ) plane", "B": "From (111) to (110) plane", "C": "From (111) to (100) plane", "D": "From (111) to (112) plane" }, "correct_answer": "A", "explanation": "The correct answer is A because cross-slip of a screw dislocation occurs between planes with the same slip direction and similar atomic packing density. The (11 ) plane shares the same Burgers vector direction [10] with (111) and has comparable stacking sequence. Option B is a common misconception due to the high symmetry of (110) planes. Option C exploits the intuitive appeal of the simple (100) plane but ignores slip system compatibility. Option D uses a plausible-looking higher-index plane that actually has different slip characteristics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2491, "question": "Calculate the length of the [0001] direction in a hexagonal crystal (in units of lattice constants a and c)", "answer": "Formula for the length of the [0001] direction in a hexagonal crystal: L = c", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算六方晶体中[0001]方向的长度，需要使用公式进行数值计算，答案是一个具体的计算结果（L = c），符合计算题的特征。 | 知识层次: 题目仅需要直接应用已知的公式（L = c）来计算[0001]方向的长度，无需多步计算或综合分析，属于基本公式的直接套用。 | 难度: 在选择题型中，该题目仅需要直接套用基本公式（L = c）进行计算，无需任何额外的步骤或组合公式。属于单一公式直接计算的简单应用层次，因此难度等级为1。", "convertible": true, "correct_option": "L = c", "choice_question": "What is the length of the [0001] direction in a hexagonal crystal (in units of lattice constants a and c)?", "conversion_reason": "The answer is a specific formula, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "L = c", "B": "L = √(a² + c²)", "C": "L = a", "D": "L = √(3)a + c" }, "correct_answer": "A", "explanation": "The correct answer is A because in hexagonal crystals, the [0001] direction corresponds to the c-axis direction only. Option B is a cognitive bias trap, mimicking the formula for diagonal length in cubic systems. Option C exploits the common misconception that all directions in hexagonal systems involve the a parameter. Option D is a multi-level trap combining basal plane diagonal (√3a) with c-axis, creating a plausible but incorrect composite length.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 518, "question": "Recrystallization", "answer": "Recrystallization: The process in which deformed materials, upon heating, undergo the replacement of deformed grains by strain-free grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Recrystallization\"进行文字解释和论述，答案是一个定义性的陈述，符合简答题的特征。 | 知识层次: 题目考查对再结晶这一基础概念的定义记忆和理解，属于材料科学中的基本概念，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆再结晶的定义和基本原理，但不需要进行复杂的分析或比较。正确选项提供了明确的定义，属于基础概念记忆层次，符合等级2的标准。", "convertible": true, "correct_option": "Recrystallization: The process in which deformed materials, upon heating, undergo the replacement of deformed grains by strain-free grains.", "choice_question": "下列关于Recrystallization的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization involves the formation of new strain-free grains that replace the deformed microstructure upon heating", "B": "Recrystallization is primarily driven by the reduction of surface energy in polycrystalline materials", "C": "Recrystallization occurs when dislocations rearrange into low-angle grain boundaries during plastic deformation", "D": "Recrystallization temperature is always 0.4 times the melting temperature (in Kelvin) for all metallic systems" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes recrystallization as the replacement of deformed grains by strain-free grains through heating. Option B is a cognitive bias trap - while surface energy is important in grain growth, it's not the primary driver for recrystallization (stored strain energy is). Option C describes recovery, not recrystallization, exploiting common confusion between these processes. Option D uses a professional intuition trap - while 0.4Tm is a common approximation, it's not universal and depends on purity and deformation conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4538, "question": "For a polymer-matrix fiber-reinforced composite, cite two reasons why there must be a strong bond between fiber and matrix at their interface.", "answer": "There must be a strong interfacial bond between fiber and matrix in order to: (1) maximize the stress transmittance between matrix and fiber phases; and (2) minimize fiber pull-out, and the probability of failure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举两个原因，并需要文字解释和论述，答案也是以文字形式给出解释，符合简答题的特征。 | 知识层次: 题目考查对纤维增强复合材料中纤维与基体界面结合作用的基本原理的记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并记忆两个具体的理由（应力传递和最小化纤维拔出），而不仅仅是简单的定义或分类。这要求考生对纤维增强复合材料界面结合的重要性有较深入的理解，而不仅仅是表面记忆。因此，相较于仅需记忆单一概念的题目（等级1），该题目难度稍高，但尚未达到需要阐述复杂概念体系的等级3。", "convertible": true, "correct_option": "maximize the stress transmittance between matrix and fiber phases and minimize fiber pull-out, and the probability of failure", "choice_question": "For a polymer-matrix fiber-reinforced composite, why must there be a strong bond between fiber and matrix at their interface?", "conversion_reason": "The answer is a standard explanation that can be converted into a correct option for a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the reasons behind the necessity of a strong bond.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To maximize stress transfer efficiency and prevent interfacial debonding under shear loads", "B": "To increase the composite's thermal conductivity through enhanced phonon coupling", "C": "To allow for reversible fiber-matrix sliding that improves impact energy absorption", "D": "To match the elastic moduli of fiber and matrix phases for uniform strain distribution" }, "correct_answer": "A", "explanation": "Correct answer A addresses the fundamental mechanical requirements of load transfer and interfacial integrity. Distractors employ sophisticated traps: B exploits thermal property confusion (phonon coupling is irrelevant to mechanical bonding), C reverses the actual requirement (sliding is detrimental to stress transfer), and D presents a plausible-but-wrong modulus matching concept (moduli differences are actually desirable for reinforcement). Advanced AI might select D due to its technical-sounding modulus matching rationale, or C due to energy absorption being a desirable composite property, both being classic material science intuition traps.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4221, "question": "Convert the (010) plane into the four-index Miller-Bravais scheme for hexagonal unit cells.", "answer": "the (010) plane in the four-index miller-bravais scheme is (01 -1 0).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求将(010)平面转换为六方晶系的四指数Miller-Bravais表示法，需要文字解释和论述转换过程，答案是一个具体的平面指数表示，而不是选择、判断或计算。 | 知识层次: 题目要求将立方晶系的(010)平面转换为六方晶系的四指数Miller-Bravais表示法，这需要理解两种晶系指数表示法的基本规则并进行直接转换，属于基本公式应用和简单计算的范畴。虽然涉及不同晶系的概念，但转换过程是直接的，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单应用难度。题目要求将(010)平面转换为六方晶系的四指数Miller-Bravais表示法，这是一个直接套用基本公式的过程。解题步骤简单，只需按照转换规则进行计算即可得出正确答案(01 -1 0)。由于题目提供了明确的转换目标，且不需要复杂的分析或比较，因此在选择题型内属于较低难度等级。", "convertible": true, "correct_option": "(01 -1 0)", "choice_question": "Convert the (010) plane into the four-index Miller-Bravais scheme for hexagonal unit cells. The correct four-index scheme is:", "conversion_reason": "The answer is a standard and specific notation in crystallography, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(01 -1 0)", "B": "(0 1 0 0)", "C": "(0 1 -1 0)", "D": "(0 1 0 -1)" }, "correct_answer": "A", "explanation": "The correct four-index Miller-Bravais scheme for the (010) plane in hexagonal unit cells is (01 -1 0), as it satisfies the condition h + k = -i. Option B is a common mistake where the fourth index is incorrectly set to zero. Option C reverses the negative sign position, exploiting visual similarity. Option D places the negative sign on the wrong index, targeting those who misremember the index conversion rules.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 915, "question": "Briefly describe the inverse segregation in the macrosegregation of ingots", "answer": "Inverse segregation: It still follows the distribution coefficient relationship, but after the formation of a large number of dendrites, the solute-enriched liquid phase will flow backward along the interdendritic channels to the vicinity of the initially solidified ingot surface, resulting in an abnormal composition distribution from the surface to the center.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述逆偏析现象，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目考查对逆偏析这一基本概念的记忆和理解，涉及定义和基本原理的解释，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求简要描述逆偏析现象，虽然涉及多个概念（如分配系数、枝晶形成、溶质富集液相流动等），但整体上仍属于对单一概念的描述性解释，不需要进行复杂的概念体系阐述或比较分析。因此属于中等难度。", "convertible": true, "correct_option": "Inverse segregation: It still follows the distribution coefficient relationship, but after the formation of a large number of dendrites, the solute-enriched liquid phase will flow backward along the interdendritic channels to the vicinity of the initially solidified ingot surface, resulting in an abnormal composition distribution from the surface to the center.", "choice_question": "Which of the following correctly describes inverse segregation in the macrosegregation of ingots?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Inverse segregation: It still follows the distribution coefficient relationship, but after the formation of a large number of dendrites, the solute-enriched liquid phase will flow backward along the interdendritic channels to the vicinity of the initially solidified ingot surface, resulting in an abnormal composition distribution from the surface to the center.", "B": "Inverse segregation occurs when the solute-depleted liquid phase moves toward the ingot center due to thermal convection, creating a higher purity zone near the surface.", "C": "Inverse segregation is caused by rapid cooling rates that prevent solute diffusion, leading to uniform solute distribution throughout the ingot cross-section.", "D": "Inverse segregation results from gravity-driven sedimentation of solute-rich phases during solidification, accumulating at the bottom of the ingot." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the mechanism of inverse segregation where solute-rich liquid flows back through dendrite channels. Option B reverses the direction of solute movement and misrepresents the composition change. Option C describes a homogenization effect rather than segregation. Option D confuses inverse segregation with gravity segregation, a different phenomenon. Advanced AIs might be misled by the plausible-sounding but incorrect descriptions in options B and D that contain elements of real metallurgical processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1655, "question": "Electronic compound", "answer": "Belongs to intermetallic compounds, where the electron concentration, defined as the ratio of the total number of valence electrons to the total number of atoms, is approximately 1.4 when the alloy reaches its maximum solubility.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Electronic compound\"进行解释和论述，答案提供了详细的文字说明，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对电子化合物（Electronic compound）的基本定义和特性的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并记忆电子化合物的定义、分类以及电子浓度的具体数值（1.4）。这比单纯记忆一个简单的定义（等级1）要复杂一些，但不需要进行复杂的分析或比较（等级3）。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "Belongs to intermetallic compounds, where the electron concentration, defined as the ratio of the total number of valence electrons to the total number of atoms, is approximately 1.4 when the alloy reaches its maximum solubility.", "choice_question": "Which of the following best describes an electronic compound?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Belongs to intermetallic compounds, where the electron concentration, defined as the ratio of the total number of valence electrons to the total number of atoms, is approximately 1.4 when the alloy reaches its maximum solubility.", "B": "A type of covalent compound where electron sharing between atoms leads to a stable electron configuration with exactly 8 valence electrons per atom.", "C": "Materials where the Fermi level lies exactly at the center of the band gap, resulting in equal numbers of electrons and holes at equilibrium.", "D": "Compounds formed when the electron-to-atom ratio equals 1.0, creating perfect charge neutrality in the crystal structure." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines electronic compounds as intermetallic compounds with specific electron concentration characteristics. Option B incorrectly applies covalent bonding concepts to intermetallics. Option C describes an impossible semiconductor condition (Fermi level at mid-gap implies intrinsic semiconductor, not electronic compounds). Option D uses a plausible but incorrect electron-to-atom ratio that would actually describe simple metals rather than electronic compounds.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4117, "question": "Compared to other ceramic materials, do ceramic-matrix composites have better oxidation resistance?", "answer": "The answer is not provided in the given information.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断陶瓷基复合材料是否比其他陶瓷材料具有更好的抗氧化性，属于判断陈述对错的题型。答案形式也符合判断题的特征。 | 知识层次: 题目考查对陶瓷基复合材料氧化抗性的基本概念记忆和理解，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆性知识，即陶瓷基复合材料与其他陶瓷材料在抗氧化性方面的比较。题目要求的是对基本概念的正误判断，不需要深入理解或复杂分析，因此属于等级1的难度。", "convertible": true, "correct_option": "The answer is not provided in the given information.", "choice_question": "Compared to other ceramic materials, do ceramic-matrix composites have better oxidation resistance?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic-matrix composites exhibit superior oxidation resistance compared to monolithic ceramics under all operating conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false due to multiple traps: 1) The absolute term 'all' is incorrect as oxidation resistance depends on specific composite composition and environmental conditions. 2) Some monolithic ceramics like alumina have excellent inherent oxidation resistance. 3) The performance depends on factors like temperature, atmosphere, and fiber/matrix interface stability. The blanket statement oversimplifies a complex materials science phenomenon.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4827, "question": "For the following pair of polymers, do the following: (1) state whether it is possible to determine whether one polymer has a higher melting temperature than the other; (2) if it is possible, note which has the higher melting temperature and then cite reason(s) for your choice; and (3) if it is not possible to decide, then state why. Linear and syndiotactic poly(vinyl chloride) having a number-average molecular weight of 500,000 g/mol; linear polyethylene having a number-average molecular weight of 225,000 g/mol", "answer": "Yes, it is possible to determine which polymer has the higher melting temperature. The linear polyethylene will have the greater melting temperature inasmuch as it will have a higher degree of crystallinity; polymers having a syndiotactic structure do not crystallize as easily as those polymers having identical single-atom side groups. With regard to molecular weight, or rather, degree of polymerization, it is about the same for both materials (8000), and therefore, is not a consideration.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，包括判断可能性、比较熔点高低并给出理由，或说明无法判断的原因。答案也以详细的文字解释形式呈现，符合简答题的特征。 | 知识层次: 题目要求比较两种聚合物的熔点，并解释原因。这涉及到对聚合物结构（线性聚乙烯和间规聚氯乙烯）和结晶度影响熔点的理解，以及分子量对熔点的影响的评估。虽然不需要复杂的计算，但需要对多个概念进行关联和综合分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合理解聚合物结构（线性与间规立构）、分子量影响、结晶度与熔点的关系等多个概念，并进行多角度比较分析。题目要求判断可能性、选择正确聚合物并解释原因，涉及多步推理和概念关联，超出基础记忆或单一概念应用层次。", "convertible": true, "correct_option": "The linear polyethylene will have the greater melting temperature inasmuch as it will have a higher degree of crystallinity; polymers having a syndiotactic structure do not crystallize as easily as those polymers having identical single-atom side groups.", "choice_question": "For the following pair of polymers, which one has a higher melting temperature and why? Linear and syndiotactic poly(vinyl chloride) having a number-average molecular weight of 500,000 g/mol; linear polyethylene having a number-average molecular weight of 225,000 g/mol", "conversion_reason": "The original question asks for a comparison and explanation, which can be rephrased as a multiple-choice question focusing on identifying the polymer with the higher melting temperature and the correct reasoning behind it.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Linear polyethylene due to its higher crystallinity from identical single-atom side groups", "B": "Syndiotactic PVC due to its higher molecular weight enhancing chain entanglement", "C": "Both polymers have similar melting points as molecular weight differences compensate for structural effects", "D": "Syndiotactic PVC due to its stereoregular structure promoting better crystal packing" }, "correct_answer": "A", "explanation": "The correct answer is A because linear polyethylene's simple structure allows for higher crystallinity, which directly increases melting temperature. Option B is a molecular weight trap - while PVC has higher Mn, entanglement doesn't significantly affect Tm. Option C is a compensation fallacy - molecular weight differences don't override fundamental crystallinity effects. Option D exploits stereoregularity misconception - while syndiotactic PVC can crystallize, it can't match PE's crystallinity due to bulky Cl side groups.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4033, "question": "A peritectic reaction involves which of the following combinations of phase fields? (a) One liquid and one solid (b) One liquid and two solid (c) two liquids and one solid (d) Three solid", "answer": "(b) One liquid and two solid", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的四个选项中选择正确的组合，符合选择题的特征 | 知识层次: 题目考查对包晶反应（peritectic reaction）基本概念的记忆和理解，涉及相图的基本知识，属于基础概念记忆范畴。 | 难度: 该题目属于基础概念记忆层次，考察的是对包晶反应（peritectic reaction）定义的理解。虽然需要记忆相场组合的具体内容，但选项设置较为直接，只需识别\"一个液体和两个固体\"的正确组合即可。相比等级1的直接概念识别，此题需要学生对相图反应类型有基本理解，属于概念理解和简单辨析的难度。", "convertible": true, "correct_option": "One liquid and two solid", "choice_question": "A peritectic reaction involves which of the following combinations of phase fields?", "conversion_reason": "The original question is already in a multiple-choice format, which can be directly used as a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A phase transition involving simultaneous nucleation of two distinct crystalline structures", "B": "A reversible solid-state transformation with hysteresis behavior", "C": "A diffusionless transformation with invariant plane strain characteristics", "D": "A displacive transformation accompanied by composition partitioning" }, "correct_answer": "C", "explanation": "Correct answer is C because martensitic transformations are defined by their diffusionless nature and invariant plane strain characteristics. Option A describes a eutectoid reaction, Option B describes a thermoelastic martensitic transformation (a special case), and Option D incorrectly introduces composition partitioning which is characteristic of diffusional transformations. The difficulty lies in the subtle distinctions between different types of phase transformations and the precise definition of martensitic transformations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 711, "question": "Wetting", "answer": "When the Gibbs free energy of the system decreases after a solid comes into contact with a liquid, it is called wetting.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对“Wetting”进行文字解释和论述，答案提供了定义和条件说明，符合简答题的特征 | 知识层次: 题目考查对wetting这一基础概念的定义和基本原理的记忆和理解，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目直接考查对\"wetting\"这一基础概念的定义记忆，只需识别Gibbs自由能降低这一关键特征即可作答。选择题型中此类直接考查定义的题目属于最低难度层级，不需要任何解释或分析过程。", "convertible": true, "correct_option": "When the Gibbs free energy of the system decreases after a solid comes into contact with a liquid, it is called wetting.", "choice_question": "Which of the following correctly defines wetting?", "conversion_reason": "The answer is a standard definition of a scientific term, which can be presented as one of multiple options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When the Gibbs free energy of the system decreases after a solid comes into contact with a liquid, it is called wetting", "B": "When the surface tension of a liquid is lower than the surface energy of a solid, spontaneous wetting occurs", "C": "The complete spreading of a liquid on a solid surface when the contact angle approaches 0°", "D": "A phenomenon where liquid molecules preferentially adsorb to solid surfaces due to van der Waals forces" }, "correct_answer": "A", "explanation": "The correct answer A is based on the thermodynamic definition of wetting. Option B is a common misconception - while related, surface tension alone doesn't determine wetting. Option C describes only the extreme case of complete wetting. Option D describes adsorption rather than wetting. Advanced AIs might choose B due to its surface-level plausibility or C due to overgeneralization from textbook examples.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3177, "question": "The lattice constant of α-Fe is $a=0.28664\\mathrm{nm}.$ When two adjacent grains form a symmetric tilt boundary with a tilt angle of 1°, calculate the spacing $D$ of the edge dislocations.", "answer": "The Burgers vector of the unit dislocation in a body-centered cubic structure is $b=\\frac{a}{2}\\textcircled{111},$ so $b={\\frac{\\sqrt{3}}{2}}a.$ Using the formula $$ D={\\frac{b}{\\theta}}={\\frac{\\sqrt{3}}{2}}\\times0.28664/0.0175\\approx14.183{\\mathrm{~nm}} $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及使用Burgers向量和倾斜角度来计算位错间距，答案是一个具体的数值结果。 | 知识层次: 题目需要理解体心立方结构中的位错概念，应用Burgers向量的计算，并运用公式进行多步计算以求解位错间距。虽然不涉及复杂的综合分析或创新应用，但需要将多个概念和计算步骤结合起来，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及晶格常数、对称倾斜晶界、位错间距等多个材料科学概念，并需要进行多步计算（包括矢量计算和角度转换）。虽然题目提供了关键公式，但需要考生正确识别和应用这些概念，属于综合性计算问题。", "convertible": true, "correct_option": "14.183 nm", "choice_question": "The lattice constant of α-Fe is $a=0.28664\\mathrm{nm}.$ When two adjacent grains form a symmetric tilt boundary with a tilt angle of 1°, the spacing $D$ of the edge dislocations is:", "conversion_reason": "The answer is a specific numerical value, which can be directly used as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "14.183 nm", "B": "0.28664 nm", "C": "16.412 nm", "D": "28.664 nm" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula D = a/θ (where θ is in radians). For 1° tilt angle (0.01745 radians), D = 0.28664 nm / 0.01745 = 14.183 nm. Option B is the lattice constant itself, exploiting the common mistake of confusing the input parameter with the result. Option C is derived from incorrectly using the Burgers vector magnitude for FCC iron (0.28664 nm × √2/2). Option D is a decimal shift trap (10× the lattice constant), playing on numerical pattern recognition biases in AI systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3357, "question": "Classify according to the interaction between alloying elements and carbon, and indicate which elements are weak carbide-forming elements", "answer": "Weak carbide-forming elements: manganese", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对合金元素与碳的相互作用进行分类，并指出哪些是弱碳化物形成元素，需要文字解释和论述，而不是简单的选择或判断。答案也以文字形式给出，符合简答题的特征。 | 知识层次: 题目考查对合金元素与碳相互作用分类的基础概念记忆，特别是弱碳化物形成元素的识别，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目仅要求记忆和识别弱碳化物形成元素（锰），属于基础概念记忆层次。题目直接给出正确选项，无需复杂推理或概念比较，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "manganese", "choice_question": "Which of the following is a weak carbide-forming element?", "conversion_reason": "The answer is a standard term (manganese), which can be presented as a single correct option among other possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "manganese", "B": "tungsten", "C": "chromium", "D": "vanadium" }, "correct_answer": "A", "explanation": "Manganese is a weak carbide-forming element because it forms less stable carbides compared to strong carbide formers like tungsten, chromium, and vanadium. The interference strategy for option B (tungsten) exploits the common misconception that all transition metals are strong carbide formers. Option C (chromium) is designed to trigger the intuitive association with stainless steel carbides. Option D (vanadium) uses the well-known fact about vanadium carbide formation in tool steels to create a plausible but incorrect choice.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 558, "question": "What are the factors affecting atomic diffusion in crystalline solids? Briefly explain the influence of temperature.", "answer": "Temperature. The higher the temperature, the greater the diffusion coefficient and the faster the diffusion rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释影响原子扩散的因素并简要说明温度的影响，答案以文字解释和论述的形式呈现，符合简答题的特征。 | 知识层次: 题目考查原子扩散影响因素的基础概念记忆，特别是温度对扩散系数和扩散速率影响的基本原理理解，属于基础概念记忆和理解范畴。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目仅要求记忆和识别影响原子扩散的因素（温度）及其基本影响（温度升高导致扩散系数增大和扩散速率加快）。不需要进行复杂的概念解释或体系阐述，解题步骤简单直接，仅需基础概念的记忆即可正确回答。", "convertible": true, "correct_option": "Temperature", "choice_question": "Which of the following factors significantly affects atomic diffusion in crystalline solids, particularly by increasing the diffusion coefficient and rate with higher values?", "conversion_reason": "The answer is a standard term (Temperature) and the explanation can be incorporated into the question stem to form a clear multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Temperature", "B": "Elastic modulus at 0K", "C": "Burgers vector magnitude", "D": "Stacking fault energy" }, "correct_answer": "A", "explanation": "Temperature is the correct answer as it exponentially increases atomic vibration and vacancy concentration, directly enhancing diffusion through the Arrhenius relationship. Elastic modulus at 0K (B) exploits cognitive bias by suggesting a fundamental material property, but at 0K diffusion is negligible regardless. Burgers vector magnitude (C) is a professional intuition trap, as while it relates to dislocations, it doesn't directly govern point defect migration. Stacking fault energy (D) creates a multi-level verification trap by being relevant for extended defects but not atomic-scale diffusion processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4492, "question": "(a) Determine the ratio of butadiene to styrene repeat units in a copolymer having a number-average molecular weight of 350,000 g/mol and degree of polymerization of 4425.", "answer": "1.0.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定共聚物中丁二烯和苯乙烯重复单元的比例，答案是一个具体的数值（1.0），这表明解答过程涉及计算步骤。 | 知识层次: 题目需要进行多步计算，涉及分子量和聚合度的概念关联，以及综合分析不同重复单元的比例。虽然计算过程较为直接，但需要理解并应用相关公式，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解共聚物组成比的计算方法，掌握数均分子量和聚合度的概念，并进行多步计算。虽然题目给出了正确选项，但解题过程涉及分子量计算、重复单元比例推导等综合分析步骤，比单纯的概念选择题更复杂。", "convertible": true, "correct_option": "1.0", "choice_question": "What is the ratio of butadiene to styrene repeat units in a copolymer with a number-average molecular weight of 350,000 g/mol and a degree of polymerization of 4425?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.0", "B": "0.75", "C": "1.25", "D": "0.5" }, "correct_answer": "A", "explanation": "The correct answer is A because the number-average molecular weight divided by the degree of polymerization gives the average molecular weight per repeat unit, which is 79.1 g/mol. This matches the average of butadiene (54 g/mol) and styrene (104 g/mol) in a 1:1 ratio. Option B (0.75) is designed to exploit the common mistake of assuming a non-integer ratio when dealing with copolymer calculations. Option C (1.25) is a reverse-ratio trap that plays on the tendency to invert relationships in polymer chemistry. Option D (0.5) is a half-ratio trap that appears plausible for certain copolymer systems but is incorrect in this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4688, "question": "For the following pairs of polymers, do the following: (1) State whether it is possible to determine whether one polymer is more likely to crystallize than the other; (2) if it is possible, note which is the more likely and then cite reason(s) for your choice; and (3) if it is not possible to decide, then state why. (c) Network phenol-formaldehyde; linear and isotactic polystyrene", "answer": "Yes, it is possible to decide for these two polymers. The linear and isotactic polystyrene is more likely to crystallize than network phenol-formaldehyde; network polymers rarely crystallize, whereas isotactic ones crystallize relatively easily.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对两种聚合物进行比较，并解释哪一种更容易结晶以及原因。这需要详细的文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求学生不仅需要理解聚合物结晶的基本原理（如网络聚合物和线性等规聚合物的结晶能力差异），还需要应用这些知识对不同类型聚合物进行比较和分析。这涉及到多个概念的关联和综合分析，而不仅仅是简单的记忆或直接套用。 | 难度: 在选择题中属于中等难度，需要理解聚合物结晶的基本原理（如网络结构vs线性结构、等规性对结晶的影响），并能对两种不同类型的聚合物（网络酚醛树脂和线性等规聚苯乙烯）进行对比分析。虽然不需要多步计算，但要求考生能够关联多个材料科学概念并做出正确判断。", "convertible": true, "correct_option": "The linear and isotactic polystyrene is more likely to crystallize than network phenol-formaldehyde; network polymers rarely crystallize, whereas isotactic ones crystallize relatively easily.", "choice_question": "For the following pairs of polymers, which one is more likely to crystallize and why? (c) Network phenol-formaldehyde; linear and isotactic polystyrene", "conversion_reason": "The original question asks for a comparison between two polymers regarding their likelihood to crystallize, which can be rephrased as a multiple-choice question with a clear correct answer. The answer provided is specific and can serve as the correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Network phenol-formaldehyde is more likely to crystallize due to its highly crosslinked structure providing regular repeating units", "B": "Linear and isotactic polystyrene is more likely to crystallize because its regular chain structure allows for efficient packing", "C": "Both polymers are equally likely to crystallize as they both have regular molecular structures", "D": "Neither polymer can crystallize because they both contain aromatic rings that disrupt chain packing" }, "correct_answer": "B", "explanation": "The correct answer is B because isotactic polystyrene's linear and stereoregular structure allows for efficient chain packing required for crystallization, while network polymers like phenol-formaldehyde cannot crystallize due to their crosslinked structure. Option A exploits the misconception that crosslinking enhances crystallinity, when it actually prevents it. Option C creates false equivalence between fundamentally different polymer architectures. Option D incorrectly generalizes that all aromatic polymers cannot crystallize, ignoring successful cases like polyethylene terephthalate.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3815, "question": "Consider a Pb-70% Sn alloy. Determine if the alloy is hypoeutectic or hypereutectic.", "answer": "hypereutectic", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断给定的合金是亚共晶还是过共晶，答案是一个明确的判断结果（hypereutectic），类似于判断题中对陈述对错的判断。 | 知识层次: 题目考查对合金成分分类（亚共晶或过共晶）的基本概念记忆和理解，不需要复杂的计算或分析。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即判断Pb-70% Sn合金是亚共晶还是过共晶。这属于最基本的概念正误判断，无需复杂推理或分析，只需记住共晶点的定义和分类即可直接作答。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "hypereutectic", "choice_question": "Consider a Pb-70% Sn alloy. Determine if the alloy is hypoeutectic or hypereutectic.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All Pb-Sn alloys with more than 61.9% Sn are hypereutectic.", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "The eutectic point in the Pb-Sn system occurs at 61.9% Sn. Alloys with Sn content above this value are indeed hypereutectic. However, students might confuse this with the hypoeutectic range (below 61.9% Sn) or misinterpret the percentage as weight percent versus atomic percent.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1405, "question": "Determine whether the following statement is correct: Point defects in crystals are a type of thermodynamic equilibrium defect, while dislocations are not thermodynamic equilibrium defects.", "answer": "Correct", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错，答案直接给出了\"Correct\"，符合判断题的特征 | 知识层次: 题目考查对晶体缺陷类型及其热力学平衡性质的基本概念记忆和理解，属于基础概念层次 | 难度: 该题目属于基本概念正误判断，仅需记忆点缺陷和位错的热力学平衡特性即可作答。在选择题型中属于最简单的直接概念判断，无需复杂分析或推理过程。", "convertible": true, "correct_option": "Correct", "choice_question": "Determine whether the following statement is correct: Point defects in crystals are a type of thermodynamic equilibrium defect, while dislocations are not thermodynamic equilibrium defects.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature regardless of their crystal structure or composition.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain ceramic materials like transformation-toughened zirconia can exhibit significant plasticity due to stress-induced phase transformations. The statement incorrectly uses 'all' as an absolute term, ignoring exceptions in advanced ceramic systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 360, "question": "Under normal circumstances, which mechanism diffuses faster?", "answer": "Diffusion via the interstitial mechanism is faster, as interstitial atoms are smaller in size and do not require the presence of vacancies.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释哪种扩散机制更快，并需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查扩散机制的基础概念记忆和理解，仅需比较间隙扩散和空位扩散的基本原理和特点，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（扩散机制），但需要考生理解并比较两种扩散机制（间隙扩散和空位扩散）的特点，并基于原子尺寸和空位需求进行判断。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Diffusion via the interstitial mechanism", "choice_question": "Under normal circumstances, which mechanism diffuses faster?", "conversion_reason": "The answer is a standard concept that can be presented as a choice among other plausible mechanisms.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial diffusion in BCC iron at 800°C", "B": "Vacancy diffusion in FCC copper at 800°C", "C": "Grain boundary diffusion in nanocrystalline nickel at 800°C", "D": "Surface diffusion on single crystal aluminum at 800°C" }, "correct_answer": "A", "explanation": "Interstitial diffusion is inherently faster than vacancy diffusion due to smaller atomic displacements required (correct answer A). Option B exploits the common misconception that FCC metals always diffuse faster than BCC. Option C uses the intuitive but incorrect assumption that grain boundary diffusion dominates at all temperatures. Option D leverages surface diffusion's high speed but ignores that it requires specific crystallographic planes to outperform interstitial diffusion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2698, "question": "If in fcc Cu, 1 out of every 500 atoms is missing, and its lattice constant is 0.3615 nm, calculate the density of Cu.", "answer": "$$ \\\\rho{=}\\\\frac{4\\\\times\\\\left(1-\\\\frac{1}{500}\\\\right)63.54}{(3.615\\\\times10^{-8})^{3}\\\\times6.023\\\\times10^{23}}{=}8.915({\\\\mathrm{g/cm}}^{3})$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解铜的密度，答案是一个具体的数值计算结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括考虑缺陷浓度对原子数量的影响、晶格常数的转换、以及密度的计算公式应用。虽然不涉及复杂的机理分析或创新设计，但需要综合运用多个概念和计算步骤，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解面心立方结构、缺陷浓度、密度计算等多个概念，并进行多步计算和综合分析。虽然题目提供了公式，但需要正确代入数值并处理单位转换，涉及一定的计算复杂度。", "convertible": true, "correct_option": "8.915 g/cm³", "choice_question": "If in fcc Cu, 1 out of every 500 atoms is missing, and its lattice constant is 0.3615 nm, the density of Cu is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.915 g/cm³", "B": "8.960 g/cm³", "C": "8.842 g/cm³", "D": "8.732 g/cm³" }, "correct_answer": "A", "explanation": "正确答案A考虑了空位缺陷对密度的精确影响计算。干扰项B是完美fcc Cu的密度，未考虑空位缺陷；干扰项C错误地使用了体心立方结构的计算方式；干扰项D则错误地将空位浓度放大10倍进行计算。这些干扰项分别利用了材料科学中常见的完美晶体假设错误、晶体结构混淆错误和浓度计算放大错误等认知偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1626, "question": "The imperfect dislocation caused by inserting or removing a close-packed plane is called _ (7) _ imperfect dislocation", "answer": "(7) Frank", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（Frank imperfect dislocation），属于需要准确回忆并填写特定知识点的简答题类型。虽然形式上类似填空题，但本质上属于简答题范畴，因为不需要选择或判断，而是直接回忆并写出答案。 | 知识层次: 题目考查对Frank不完全位错这一基本概念的记忆和理解，属于定义和分类的记忆性知识。 | 难度: 在选择题型中，此题仅考察对Frank不全位错这一基础定义的单点记忆，无需解释或分析。属于最基本的概念记忆题，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Frank", "choice_question": "The imperfect dislocation caused by inserting or removing a close-packed plane is called:", "conversion_reason": "The answer is a standard term (Frank), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Frank", "B": "Shockley", "C": "Stair-rod", "D": "Lomer-Cottrell" }, "correct_answer": "A", "explanation": "Frank imperfect dislocations result from inserting or removing a close-packed plane, creating stacking faults. Shockley dislocations (B) are partial dislocations that glide between close-packed planes, a common first-guess error. Stair-rod dislocations (C) form at intersections of stacking faults, exploiting visual analogy. Lomer-Cottrell dislocations (D) are sessile dislocations formed by reactions, targeting confusion with other immobile defects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 813, "question": "For a face-centered cubic crystal with a movable slip system of (111)[110], if the slip is caused by an edge dislocation, indicate the direction of the dislocation line.", "answer": "Direction of the dislocation line: [112]", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案是一个具体的晶体学方向[112]，而不是从多个选项中选择或进行数值计算。 | 知识层次: 题目要求学生在理解面心立方晶体滑移系统的基础上，结合位错理论，分析刃位错线的方向。这需要学生将晶体学方向与位错性质相关联，进行多步推理和综合分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合理解面心立方晶体的滑移系统、位错类型（刃位错）以及位错线方向的计算。解题步骤涉及晶体几何学知识、滑移系分析以及位错线方向的确定，需要多步计算和概念关联。虽然题目给出了正确选项，但推导过程需要较强的空间想象力和综合分析能力，超出了基础记忆或简单应用的范畴。", "convertible": true, "correct_option": "[112]", "choice_question": "For a face-centered cubic crystal with a movable slip system of (111)[110], if the slip is caused by an edge dislocation, what is the direction of the dislocation line?", "conversion_reason": "The answer is a standard term (direction) in crystallography, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[112]", "B": "[110]", "C": "[111]", "D": "[121]" }, "correct_answer": "A", "explanation": "The correct answer is A because for an edge dislocation in FCC crystals with (111)[110] slip system, the dislocation line direction must be perpendicular to the Burgers vector [110]. The cross product of the slip plane normal [111] and Burgers vector [110] gives [112]. Option B is a common mistake as it matches the Burgers vector direction but ignores the perpendicularity requirement. Option C exploits confusion with the slip plane normal. Option D is a mathematically plausible but crystallographically incorrect variant of the correct answer.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2025, "question": "The theoretical strength of amorphous materials is calculated to be $G/6\\\\sim G/4$, where $G$ is the shear modulus. Given $\\\\nu=0.25$, estimate the theoretical strength of glass (an amorphous material) based on its elastic properties (given $E=70~000~\\\\mathrm{MPa}$).", "answer": "Therefore, the theoretical strength ranges between 0.4E and 0.4E, that is, $$4~900\\\\sim7~000~\\\\mathrm{MPa}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求基于给定的弹性模量（E=70 000 MPa）和泊松比（ν=0.25）计算玻璃的理论强度范围。解答过程涉及数值计算和公式应用（G=E/2(1+ν)），最终给出数值结果（4 900~7 000 MPa）。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，需要根据给定的弹性模量和泊松比计算理论强度范围，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目要求基于给定的弹性模量E和泊松比ν，通过基本公式（G=E/[2(1+ν)]）计算剪切模量G，然后直接套用理论强度范围公式（G/6~G/4）进行计算。虽然涉及两个步骤，但都是直接套用基础公式，无需复杂推导或概念整合，因此在选择题型中属于等级2难度。", "convertible": true, "correct_option": "4 900~7 000 MPa", "choice_question": "Given the elastic properties of glass (E=70 000 MPa, ν=0.25), the theoretical strength of glass as an amorphous material is estimated to be in the range of:", "conversion_reason": "The answer is a specific range of values, which can be presented as a choice among other plausible but incorrect ranges.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4 900~7 000 MPa", "B": "17 500~23 333 MPa", "C": "70~93 GPa", "D": "10 500~14 000 MPa" }, "correct_answer": "A", "explanation": "正确答案A基于理论强度公式G/6~G/4，其中G=E/2(1+ν)=28 000 MPa。干扰项B直接使用E/4~E/3，混淆了E和G的关系。干扰项C正确计算了G值但错误保持了G的单位。干扰项D使用E/6~E/4，是常见但错误的直觉判断。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1132, "question": "The typical crystal structure types of metals are (1), (2), and (3). What are their names?", "answer": "(1) fcc; (2) bcc; (3) hcp;", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写金属的典型晶体结构类型名称，答案需要提供具体的结构名称（fcc, bcc, hcp），属于简答形式而非选择、判断或计算。 | 知识层次: 题目考查金属典型晶体结构类型的基本概念记忆，只需回忆并列举出常见的三种结构名称（fcc、bcc、hcp），不涉及应用、分析或综合等高阶认知能力。 | 难度: 在选择题型中，该题目仅要求记忆金属的三种典型晶体结构类型（fcc、bcc、hcp），属于基础概念记忆，无需解释或分析。解题步骤简单，只需直接回忆知识点即可选择正确答案，因此在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "fcc, bcc, hcp", "choice_question": "Which of the following are the typical crystal structure types of metals?", "conversion_reason": "The answer consists of standard terms (fcc, bcc, hcp) which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "fcc, bcc, hcp", "B": "fcc, bcc, diamond cubic", "C": "bcc, hcp, simple cubic", "D": "fcc, hcp, zinc blende" }, "correct_answer": "A", "explanation": "The correct answer is A because face-centered cubic (fcc), body-centered cubic (bcc), and hexagonal close-packed (hcp) are the three most common crystal structures for metallic elements. Option B is incorrect because diamond cubic is a covalent structure typical of semiconductors like silicon, not metals. Option C is incorrect because simple cubic is extremely rare in pure metals due to its low packing efficiency. Option D is incorrect because zinc blende is another covalent structure found in compound semiconductors like ZnS, not pure metals. These incorrect options exploit common cognitive biases by mixing metallic structures with similar-looking but fundamentally different semiconductor structures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2510, "question": "What is the crystal structure of graphite?", "answer": "The crystal structure of graphite is a simple hexagonal lattice, with carbon atoms located at the lattice points.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释石墨的晶体结构，答案提供了详细的描述而非选择或判断 | 知识层次: 题目考查对石墨晶体结构这一基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆石墨的基本晶体结构（简单六方晶格），属于基础概念记忆层次。题目仅涉及单一知识点，无需复杂分析或比较，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "A simple hexagonal lattice, with carbon atoms located at the lattice points", "choice_question": "What is the crystal structure of graphite?", "conversion_reason": "The answer is a standard term describing the crystal structure of graphite, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Simple hexagonal lattice with carbon atoms at lattice points", "B": "Face-centered cubic structure with alternating layers", "C": "Body-centered tetragonal structure with covalent bonding", "D": "Hexagonal close-packed structure with ABAB stacking sequence" }, "correct_answer": "A", "explanation": "The correct answer is A because graphite has a simple hexagonal lattice structure where carbon atoms are arranged in planar sheets with strong covalent bonds within the layer and weak van der Waals forces between layers. Option B is a cognitive bias trap, exploiting the common misconception that layered structures must be FCC. Option C uses a body-centered tetragonal structure which is completely wrong but sounds plausible due to the mention of covalent bonding. Option D is a professional intuition trap, using HCP stacking which is similar to graphite's layered structure but incorrect in atomic arrangement details.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3516, "question": "Compare the forgeability of HT150 and annealed 20 steel", "answer": "The forgeability of 20 steel is better than that of HT150 (HT150 cannot be forged).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的可锻性，答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求比较两种材料的可锻性，需要理解材料的基本性质（如HT150是铸铁不可锻造，20钢经退火后可锻造性较好），并能够将这些概念关联起来进行综合分析。虽然不涉及复杂计算，但需要对材料性质有较深入的理解和应用能力。 | 难度: 在选择题中属于中等难度，需要理解HT150和20钢的锻造性能差异，并综合分析材料状态（退火）对锻造性能的影响。虽然不需要多步计算，但需要关联材料特性和工艺知识进行判断。", "convertible": true, "correct_option": "The forgeability of 20 steel is better than that of HT150 (HT150 cannot be forged).", "choice_question": "Compare the forgeability of HT150 and annealed 20 steel:", "conversion_reason": "The answer is a standard comparison statement that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "HT150 has better forgeability due to its higher carbon content improving hot workability", "B": "Annealed 20 steel has better forgeability because its lower carbon content reduces cracking risk during deformation", "C": "Both materials have similar forgeability as they are in annealed condition", "D": "HT150 cannot be forged while annealed 20 steel has moderate forgeability" }, "correct_answer": "D", "explanation": "Correct answer is D because HT150 is a cast iron (cannot be forged) while annealed 20 steel is forgeable. A is wrong but tempting as it uses the common misconception that higher carbon improves hot workability (actually the opposite). B is partially correct but misleading by not mentioning HT150's fundamental unforgeability. C is a symmetry trap exploiting the annealed condition mention while ignoring material class differences.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1301, "question": "Why do metal crystals always slide along the slip plane and slip direction during the slip process?", "answer": "The slip of metal crystals is the result of dislocation movement, and the dislocation movement is mainly subjected to the resistance of the crystal lattice. In the crystal, the greater the interplanar spacing between the densest atomic planes, and the smaller the atomic spacing in the most closely packed direction, the smaller the sliding resistance when dislocations slide along the slip plane and slip direction. Therefore, metal crystals always slide along the slip plane and slip direction during the slip process.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释金属晶体在滑移过程中为何总是沿滑移面和滑移方向滑动，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释金属晶体滑移过程中的机理，涉及位错运动、晶格阻力、原子面间距和方向等复杂概念的综合分析和推理。需要深入理解晶体结构和位错理论，并能够将这些概念关联起来进行解释。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求深入理解金属晶体滑移的微观机制，包括位错运动、晶格阻力、密排面和密排方向等复杂概念的综合运用。正确选项不仅需要解释滑移现象，还需要分析晶面间距和原子间距对滑移阻力的影响机理。这种题目要求考生具备将多个高阶材料科学原理进行系统性整合和推理分析的能力，远超单纯记忆或简单应用层面，属于选择题型中最复杂的机理深度解释类题目。", "convertible": true, "correct_option": "The slip of metal crystals is the result of dislocation movement, and the dislocation movement is mainly subjected to the resistance of the crystal lattice. In the crystal, the greater the interplanar spacing between the densest atomic planes, and the smaller the atomic spacing in the most closely packed direction, the smaller the sliding resistance when dislocations slide along the slip plane and slip direction. Therefore, metal crystals always slide along the slip plane and slip direction during the slip process.", "choice_question": "Why do metal crystals always slide along the slip plane and slip direction during the slip process?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because the slip plane and direction have the highest elastic modulus, providing structural stability during deformation", "B": "Due to the minimum critical resolved shear stress required for dislocation motion along these crystallographic orientations", "C": "As a result of the maximum atomic packing density creating the shortest Burgers vector in these directions", "D": "Owing to the thermal vibration amplitude being minimized along these specific crystallographic planes" }, "correct_answer": "B", "explanation": "The correct answer is B because slip occurs along planes and directions requiring the minimum critical resolved shear stress, which correlates with the largest interplanar spacing and smallest atomic spacing. Option A is incorrect as it confuses elastic modulus with shear stress requirements. Option C is a half-truth as while atomic packing is dense, the key factor is Burgers vector magnitude, not just density. Option D introduces an irrelevant thermal vibration factor that doesn't determine slip systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3064, "question": "What is special ceramics?", "answer": "To improve the performance of ordinary ceramics, it was found that the impurities brought by natural raw materials were quite unfavorable. Therefore, high-purity artificially synthesized raw materials were adopted, and the forming and sintering processes of ordinary ceramics were followed to produce new types of ceramics. These ceramics are called special ceramics, such as oxide ceramics and piezoelectric ceramics.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对“特殊陶瓷”进行定义和解释，答案提供了详细的文字论述，符合简答题的特征。 | 知识层次: 题目考查特殊陶瓷的定义和基本原理，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项提供了较为详细的解释和描述，包括特殊陶瓷的定义、产生背景、制作方法以及具体例子。这要求考生不仅要记住基本定义，还需要理解相关背景知识和具体应用实例。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "To improve the performance of ordinary ceramics, it was found that the impurities brought by natural raw materials were quite unfavorable. Therefore, high-purity artificially synthesized raw materials were adopted, and the forming and sintering processes of ordinary ceramics were followed to produce new types of ceramics. These ceramics are called special ceramics, such as oxide ceramics and piezoelectric ceramics.", "choice_question": "What is special ceramics?", "conversion_reason": "The answer is a standard definition of special ceramics, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ceramics produced using high-purity synthetic raw materials to achieve superior properties compared to traditional ceramics", "B": "Ceramics that exhibit superconductivity at room temperature through special doping techniques", "C": "Traditional ceramics modified with polymer additives to enhance ductility", "D": "Ceramics processed using only natural raw materials but with nanostructured grain boundaries" }, "correct_answer": "A", "explanation": "The correct answer is A because special ceramics are indeed characterized by the use of high-purity synthetic raw materials to overcome limitations of traditional ceramics. Option B is incorrect because no ceramics exhibit room-temperature superconductivity. Option C describes polymer-ceramic composites, not special ceramics. Option D is wrong because special ceramics specifically avoid natural raw materials due to impurities.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3477, "question": "For a machine tool spindle made of 40Cr steel, the core requires good strength and toughness (200-300HB), while the journal needs to be hard and wear-resistant (HRC54-58). Describe the microstructure after preparatory heat treatment.", "answer": "Microstructure after preparatory heat treatment: tempered sorbite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求描述预备热处理后的微观结构，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对材料热处理后微观结构的基本概念记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别40Cr钢经过预备热处理后的微观组织（回火索氏体），属于基础概念记忆层面的知识，无需解释或分析过程，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "tempered sorbite", "choice_question": "For a machine tool spindle made of 40Cr steel, the core requires good strength and toughness (200-300HB), while the journal needs to be hard and wear-resistant (HRC54-58). What is the microstructure after preparatory heat treatment?", "conversion_reason": "The answer is a standard term (tempered sorbite), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "tempered sorbite", "B": "pearlite with retained austenite", "C": "bainite with martensite islands", "D": "spheroidized cementite in ferrite matrix" }, "correct_answer": "A", "explanation": "The correct answer is tempered sorbite because 40Cr steel after preparatory heat treatment (quenching + high tempering) forms this microstructure which provides optimal core properties. Option B exploits the common misconception about retained austenite in medium-carbon steels. Option C creates confusion between preparatory and final heat treatment microstructures. Option D mimics the appearance of annealed state which is incorrect for this processing stage.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 129, "question": "Analyze the reason why monovalent alkali metal oxides reduce the viscosity of silicate melts.", "answer": "Generally, alkali metal oxides (Li2O, Na2O, K2O, Rb2O, Cs2O) can reduce melt viscosity. These cations, due to their small charge, large radius, and weak interaction with O2-, provide 'free oxygen' in the system, increasing the O/Si ratio. This causes the original silicon-oxygen anion groups to depolymerize into simpler structural units, thereby reducing the activation energy and decreasing viscosity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析碱金属氧化物降低硅酸盐熔体粘度的原因，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求分析碱金属氧化物降低硅酸盐熔体粘度的原因，涉及离子特性（小电荷、大半径、弱相互作用）、氧硅比变化、硅氧阴离子基团的解聚以及活化能降低等多个方面的综合分析和机理解释。这需要深入理解材料科学中的结构-性能关系，并进行多因素的推理分析。 | 难度: 在选择题型中，该题目属于最高难度等级。它要求考生不仅掌握碱金属氧化物的基本性质，还需要深入理解硅酸盐熔体粘度的变化机理。题目涉及多个复杂概念的综合运用，包括阳离子特性（电荷、半径）、氧硅比变化、硅氧阴离子基团的解聚过程以及活化能的影响机制。这种需要从微观结构角度解释宏观性质变化的题目，在选择题型中属于对知识深度和综合分析能力要求极高的类型。", "convertible": true, "correct_option": "These cations, due to their small charge, large radius, and weak interaction with O2-, provide 'free oxygen' in the system, increasing the O/Si ratio. This causes the original silicon-oxygen anion groups to depolymerize into simpler structural units, thereby reducing the activation energy and decreasing viscosity.", "choice_question": "Why do monovalent alkali metal oxides reduce the viscosity of silicate melts?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Monovalent cations increase the O/Si ratio by providing 'free oxygen', causing depolymerization of silicate networks", "B": "Alkali metals preferentially bond with silicon, creating more fluid Si-O-Al structures", "C": "The large ionic radius of alkali metals physically disrupts the silicate network structure", "D": "Charge compensation effects reduce the overall bond strength in the melt" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual mechanism where monovalent cations provide free oxygen that breaks up polymerized networks. B is wrong because alkali metals don't preferentially bond with Si over O. C is a partial truth trap - while size matters, it's not the primary mechanism. D sounds plausible but misrepresents the charge compensation concept that applies to multivalent cations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4689, "question": "For the following pairs of polymers, do the following: (1) State whether it is possible to determine whether one polymer is more likely to crystallize than the other; (2) if it is possible, note which is the more likely and then cite reason(s) for your choice; and (3) if it is not possible to decide, then state why. (d) Block poly(acrylonitrile-isoprene) copolymer; graft poly(chloroprene-isobutylene) copolymer", "answer": "Yes, it is possible to decide for these two copolymers. The block poly(acrylonitrileisoprene) copolymer is more likely to crystallize than the graft poly(chloroprene-isobutylene) copolymer. Block copolymers crystallize more easily than graft ones.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对两种聚合物的结晶可能性进行比较和解释，需要文字论述和理由说明，而不是简单的选择或判断。答案也提供了详细的解释和原因，符合简答题的特征。 | 知识层次: 题目要求对不同类型共聚物的结晶能力进行比较和判断，需要理解共聚物结构（嵌段与接枝）对结晶行为的影响，并进行综合分析。这涉及多个概念的关联和中等程度的推理分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生能够区分不同类型的共聚物（嵌段共聚物和接枝共聚物）的结晶能力，并理解其背后的原因。虽然题目提供了明确的选项，但考生需要掌握共聚物结构对结晶性能的影响这一知识点，并进行综合分析才能正确选择。这涉及到中等应用层次的知识，包括多步计算、概念关联和综合分析。", "convertible": true, "correct_option": "The block poly(acrylonitrile-isoprene) copolymer is more likely to crystallize than the graft poly(chloroprene-isobutylene) copolymer.", "choice_question": "For the following pairs of polymers, which one is more likely to crystallize? (d) Block poly(acrylonitrile-isoprene) copolymer; graft poly(chloroprene-isobutylene) copolymer", "conversion_reason": "The original question asks for a comparison between two polymers regarding their likelihood to crystallize, and the answer provides a clear, definitive choice. This can be rephrased as a multiple-choice question where the correct option is explicitly stated in the original answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Block poly(acrylonitrile-isoprene) due to its regular chain arrangement allowing better packing", "B": "Graft poly(chloroprene-isobutylene) because chloroprene segments can form crystalline domains", "C": "Both have equal crystallization tendency as they contain similar polar/nonpolar ratios", "D": "Neither can crystallize due to their copolymer nature disrupting regularity" }, "correct_answer": "A", "explanation": "The block copolymer (A) is correct because its alternating block structure allows for sufficient chain regularity in acrylonitrile segments to form crystalline regions. B is misleading because while chloroprene can crystallize, the graft structure disrupts chain packing. C exploits the similarity fallacy - polar/nonpolar ratio alone doesn't determine crystallinity. D is an absolute statement trap, ignoring that block copolymers can maintain partial crystallinity.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3244, "question": "Which of the following statements about dislocation loops is correct? A. A dislocation loop cannot be entirely edge dislocation everywhere. B. A dislocation loop can be entirely edge dislocation everywhere. C. A dislocation loop must simultaneously contain both edge dislocation and screw dislocation. D. A dislocation loop must simultaneously contain edge dislocation, screw dislocation, and mixed dislocation.", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从四个选项中选择关于位错环的正确陈述，符合选择题的特征 | 知识层次: 题目考查对位错环基本概念的理解，属于对位错类型（刃型位错和螺型位错）及其在环状结构中分布情况的记忆性知识。 | 难度: 在选择题中属于中等偏下难度，需要理解位错环的基本概念和类型，并能区分边缘位错和螺型位错的特征。虽然涉及概念辨析，但不需要复杂的分析步骤。", "convertible": true, "correct_option": "B. A dislocation loop can be entirely edge dislocation everywhere.", "choice_question": "Which of the following statements about dislocation loops is correct?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Burgers vector of a dislocation loop must lie in the loop plane", "B": "A perfect dislocation loop in FCC metals always dissociates into partials", "C": "Dislocation loops in BCC metals cannot have pure screw character", "D": "The strain field of a circular prismatic loop exhibits cubic symmetry" }, "correct_answer": "A", "explanation": "Correct answer is A because the Burgers vector must indeed lie in the plane of a pure prismatic loop. B is incorrect because perfect loops don't always dissociate - it depends on stacking fault energy. C is wrong as BCC metals can have screw dislocations. D is false because prismatic loops have cylindrical, not cubic symmetry. The options exploit common misconceptions about dislocation core structures and symmetry properties in different crystal systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 590, "question": "Explain the term: Lomer-Cottrell dislocation", "answer": "Lomer-Cottrell dislocation: In dislocation reactions, when perfect dislocations on different slip planes in FCC crystals decompose into partial dislocations, the leading partial dislocations react to form new immobile dislocations, resulting in an immobile dislocation configuration where three partial dislocations are separated by two stacking faults.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释术语\"Lomer-Cottrell dislocation\"，需要文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对Lomer-Cottrell dislocation这一基本概念的定义和基本原理的记忆和理解，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目要求考生解释Lomer-Cottrell dislocation的定义和形成过程，属于概念解释和描述的难度等级。虽然涉及多个概念（如perfect dislocations、partial dislocations、stacking faults等），但不需要进行复杂的比较分析或深入的概念体系阐述，因此属于中等难度。", "convertible": true, "correct_option": "Lomer-Cottrell dislocation: In dislocation reactions, when perfect dislocations on different slip planes in FCC crystals decompose into partial dislocations, the leading partial dislocations react to form new immobile dislocations, resulting in an immobile dislocation configuration where three partial dislocations are separated by two stacking faults.", "choice_question": "Which of the following best describes the term 'Lomer-Cottrell dislocation'?", "conversion_reason": "The answer is a standard definition of a technical term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A sessile dislocation formed by the reaction of two partial dislocations on intersecting {111} planes in FCC crystals, creating an immobile configuration with stacking faults", "B": "A glissile dislocation formed by the interaction of perfect dislocations on parallel slip planes in BCC crystals, enabling cross-slip mechanisms", "C": "A special type of edge dislocation that forms at grain boundaries in HCP crystals, responsible for deformation twinning", "D": "A mobile dislocation configuration in FCC crystals where three perfect dislocations combine to form a superdislocation" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the Lomer-Cottrell dislocation as an immobile configuration formed by partial dislocations on intersecting {111} planes in FCC crystals, which matches the textbook definition. Option B is wrong but tempting because it uses correct dislocation terminology ('glissile') but incorrectly places it in BCC crystals and describes cross-slip. Option C exploits the common confusion between FCC and HCP crystal structures and their deformation mechanisms. Option D is dangerous because it mimics the 'three dislocations' aspect of the correct answer but incorrectly describes them as perfect dislocations forming a mobile configuration.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4030, "question": "At a eutectic point on a binary temperature-composition phase diagrams, how many phases are present when the system is at equilibrium?(a) 0(b) 1(c) 2(d) 3", "answer": "At a eutectic point on a binary phase diagram, three phases (Liquid, \\alpha, and \\beta ) are present when the system is at equilibrium.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项（a、b、c、d）中选择正确答案，符合选择题的特征。 | 知识层次: 题目考查对二元相图中共晶点处相平衡状态的基本概念记忆，属于对基本原理的记忆性知识。 | 难度: 该题目属于基础概念记忆题，直接考察对共晶点相数的记忆。在选择题型中，只需识别并回忆\"共晶点三相共存\"这一基本概念即可作答，无需任何分析或推理过程，属于最简单的直接记忆型题目。", "convertible": true, "correct_option": "(d) 3", "choice_question": "At a eutectic point on a binary temperature-composition phase diagrams, how many phases are present when the system is at equilibrium?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer provided. Therefore, it can be directly used as a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2 (liquid + single solid solution phase)", "B": "2 (two distinct solid phases)", "C": "3 (liquid + two solid phases)", "D": "1 (single homogeneous liquid phase)" }, "correct_answer": "C", "explanation": "The correct answer is C because at a eutectic point, three phases (liquid and two distinct solid phases) coexist in equilibrium. Option A is a cognitive bias trap, exploiting the common misconception that binary systems can only form single solid solutions. Option B is a professional intuition trap, using the correct number of phases but wrong composition (two solids without liquid). Option D targets the erroneous assumption that eutectic points represent single-phase regions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 5, "correct_answers": 5, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1670, "question": "At phase equilibrium, the number of phases in the system can be calculated using the relationship between the degrees of freedom of the system, －（9）__, and the number of external factors that can influence the equilibrium state of the system", "answer": "（9）number of components", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（number of components）来补全句子，而不是从多个选项中选择或进行判断、计算。这符合简答题的特征，即需要提供具体的文字答案。 | 知识层次: 题目考查对相平衡中自由度、组分数和相数之间关系的基本概念记忆，属于Gibbs相律的基础知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接考察对相平衡中组分数（number of components）这一基础概念的记忆，无需复杂推理或概念间的关联分析。正确选项明确对应教材中的定义性内容，属于最基础的知识点考察。", "convertible": true, "correct_option": "number of components", "choice_question": "At phase equilibrium, the number of phases in the system can be calculated using the relationship between the degrees of freedom of the system, －（9）__, and the number of external factors that can influence the equilibrium state of the system. Which of the following correctly fills in the blank (9)?", "conversion_reason": "The answer is a standard term ('number of components'), making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "number of components", "B": "Gibbs free energy", "C": "chemical potential", "D": "entropy of mixing" }, "correct_answer": "A", "explanation": "The correct answer is A because the Gibbs phase rule explicitly relates the degrees of freedom (F) to the number of components (C) and phases (P) as F = C - P + 2. Option B is a cognitive bias trap - while Gibbs free energy is central to phase equilibrium, it's not the variable in the phase rule relationship. Option C exploits professional intuition - chemical potential is related but not the correct term for this specific relationship. Option D is a multi-level verification trap - entropy is important in phase stability but irrelevant to the phase rule's mathematical formulation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 9, "question": "Calculate the number of atoms in a face-centered cubic unit cell", "answer": "Number of atoms 4", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算面心立方晶胞中的原子数），答案是一个具体的数值（4），解答过程需要应用材料科学中的晶体结构知识进行计算。 | 知识层次: 题目要求计算面心立方晶胞中的原子数，这需要应用基本的晶体结构知识（面心立方晶胞的特点）和简单的数学计算（每个角原子和面心原子的贡献）。虽然需要理解晶胞结构的基本概念，但计算过程直接且不涉及多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用面心立方晶胞原子数的基本公式（4个原子），无需任何额外计算或概念组合。属于单一公式直接应用的等级1难度。", "convertible": true, "correct_option": "4", "choice_question": "What is the number of atoms in a face-centered cubic unit cell?", "conversion_reason": "The answer to the calculation question is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4", "B": "选项D", "C": "选项B", "D": "选项C" }, "correct_answer": "A", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 4286, "question": "Two previously undeformed cylindrical specimens of an alloy are to be strain hardened by reducing their cross-sectional areas (while maintaining their circular cross sections). For one specimen, the initial and deformed radii are 16mm and 11 mm, respectively. The second specimen, with an initial radius of 12 mm, must have the same deformed hardness as the first specimen; compute the second specimen's radius after deformation.", "answer": "the second specimen's radius after deformation is 8.25 mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（如应变硬化公式）来求解第二个试样变形后的半径，答案是一个具体的数值结果（8.25 mm），属于典型的计算题特征。 | 知识层次: 题目需要进行多步计算，包括应变计算和硬度关联分析，涉及概念关联和综合分析。虽然不涉及复杂的推理或创新应用，但需要理解应变硬化原理并进行相应的数值计算。 | 难度: 在选择题中属于中等难度，需要理解应变硬化概念、计算截面面积变化率并进行多步计算。题目涉及两个试样的对比分析，要求考生能够综合应用材料科学知识解决实际问题。虽然计算步骤较多，但在选择题型中通过选项可以辅助验证结果，降低了部分难度。", "convertible": true, "correct_option": "8.25 mm", "choice_question": "Two previously undeformed cylindrical specimens of an alloy are to be strain hardened by reducing their cross-sectional areas (while maintaining their circular cross sections). For one specimen, the initial and deformed radii are 16mm and 11 mm, respectively. The second specimen, with an initial radius of 12 mm, must have the same deformed hardness as the first specimen; what is the second specimen's radius after deformation?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.25 mm", "B": "9.18 mm", "C": "7.07 mm", "D": "10.39 mm" }, "correct_answer": "A", "explanation": "正确答案A是通过计算真实应变得到的精确结果。干扰项B利用了对数应变计算中的常见错误，将面积比直接开方而非取对数。干扰项C基于错误的假设，认为硬度与直径减少量而非应变相关。干扰项D则利用了弹性变形与塑性变形的概念混淆，采用了弹性模量计算方式。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 740, "question": "What are the two types of arrangements in the closest packing of equal-sized spheres?", "answer": "(2) Cubic close packing; (3) Hexagonal close packing", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举两种最密堆积方式，需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查对等径球最密堆积两种排列方式的基础概念记忆，属于材料科学中最基本的晶体结构知识，仅需回忆和识别两种类型（立方最密堆积和六方最密堆积），不涉及应用或分析过程。 | 难度: 在选择题型中，该题目仅要求记忆两种最密堆积方式的名称（立方最密堆积和六方最密堆积），属于基础概念的直接回忆，无需解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Cubic close packing; Hexagonal close packing", "choice_question": "Which of the following are the two types of arrangements in the closest packing of equal-sized spheres?", "conversion_reason": "The answer to the short answer question is a standard terminology or concept, which can be converted into a multiple-choice format by listing the correct options among other plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cubic close packing and Hexagonal close packing", "B": "Face-centered cubic and Body-centered cubic", "C": "Hexagonal close packing and Simple cubic", "D": "Cubic close packing and Tetragonal close packing" }, "correct_answer": "A", "explanation": "The correct answer is A because cubic close packing (CCP) and hexagonal close packing (HCP) are the two distinct arrangements for closest packing of equal-sized spheres. Option B is incorrect because while face-centered cubic is equivalent to CCP, body-centered cubic is not a closest packing arrangement. Option C is wrong as simple cubic is not a close packing structure. Option D is misleading because tetragonal close packing is not a standard classification in sphere packing theory.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 2, "correct_answers": 2, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2288, "question": "A contact device is made of silver-tungsten composite material. Its production process involves first creating a porous tungsten powder metallurgy blank, and then infiltrating pure silver into the pores. Before silver infiltration, the density of the tungsten compact is 14.5 g/cm³. Calculate the mass fraction of silver in the blank after infiltration. The densities of pure tungsten and pure silver are 19.3 g/cm³ and 10.49 g/cm³, respectively. Assume the tungsten blank is very thin and entirely composed of open pores.", "answer": "The mass fraction of silver after infiltration is wAg = (0.25 × 10.49) / (0.25 × 10.49 + 0.75 × 19.3) = 15.4%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及密度、质量分数等物理量的计算，答案也是通过具体计算得出的数值结果。 | 知识层次: 题目需要进行多步计算，涉及密度、质量分数等概念的综合应用，需要理解孔隙率和材料复合的原理，并进行适当的公式推导和数值计算。虽然不涉及复杂的推理分析或创新设计，但比简单的直接套用公式要复杂一些。 | 难度: 在选择题中属于中等偏上难度，需要理解多孔材料的密度计算、质量分数的概念，并进行多步骤的综合计算。题目涉及多个物理概念的关联应用，且计算过程需要一定的综合分析能力。", "convertible": true, "correct_option": "15.4%", "choice_question": "A contact device is made of silver-tungsten composite material. Its production process involves first creating a porous tungsten powder metallurgy blank, and then infiltrating pure silver into the pores. Before silver infiltration, the density of the tungsten compact is 14.5 g/cm³. The mass fraction of silver in the blank after infiltration is: (The densities of pure tungsten and pure silver are 19.3 g/cm³ and 10.49 g/cm³, respectively. Assume the tungsten blank is very thin and entirely composed of open pores.)", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "15.4%", "B": "24.8%", "C": "10.2%", "D": "18.6%" }, "correct_answer": "A", "explanation": "正确答案A(15.4%)通过计算钨骨架孔隙率和银填充质量得出。干扰项B(24.8%)利用直觉错误地将密度比直接转换为质量分数；C(10.2%)错误地假设孔隙率与银含量线性相关；D(18.6%)则混淆了体积分数与质量分数的计算。这些干扰项专门针对AI在材料复合计算中常见的单位混淆和比例关系误解设计。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 28, "question": "In MgS, the unit cell parameter a=0.5201 nm, and the anions are in contact with each other. Calculate the radius of S2-.", "answer": "In MgS, a=0.5201 nm, and the anions are in contact with each other, a=2√2 r-, thus rS2-=0.5201 nm / (2√2) = 0.177 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，具体涉及单位晶胞参数和离子半径的计算，答案也是通过数学运算得出的具体数值。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，即通过给定的晶胞参数和几何关系（a=2√2 r-）来计算离子半径，不需要多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（a=2√2 r-）进行计算，解题步骤简单且直接，无需多个公式组合或复杂分析。属于最基础的难度等级。", "convertible": true, "correct_option": "0.177 nm", "choice_question": "In MgS, the unit cell parameter a=0.5201 nm, and the anions are in contact with each other. What is the radius of S2-?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.177 nm", "B": "0.184 nm", "C": "0.260 nm", "D": "0.368 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.177 nm) because in an FCC structure with anions in contact, the S2- radius is calculated as (√2/4)*a. The distractor B (0.184 nm) exploits the common mistake of using the wrong face diagonal calculation (√3/4)*a for body-centered structures. Option C (0.260 nm) is half the lattice parameter, a tempting oversimplification. Option D (0.368 nm) is derived from incorrectly assuming the anion-cation distance equals the anion radius.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1887, "question": "4. Melt is a high-energy state of matter existing above the liquidus temperature, and during the cooling process of the melt, three different phase transition processes can occur: (11), (12), and (13).", "answer": "(11) Crystallization; (12) Vitrification; (13) Phase separation", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写三个不同的相变过程，需要考生根据知识进行简短的文字回答，而不是从选项中选择或进行判断、计算。 | 知识层次: 题目考查对熔体冷却过程中三种相变过程的基本概念记忆，属于基础概念的记忆性知识，无需复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确区分并记忆三种不同的相变过程（结晶、玻璃化和相分离）。这比单纯记忆单一概念的定义（等级1）要求更高，但不需要进行复杂的概念体系阐述或比较分析（等级3）。", "convertible": true, "correct_option": "Crystallization; Vitrification; Phase separation", "choice_question": "During the cooling process of the melt, which of the following are the three different phase transition processes that can occur?", "conversion_reason": "The original short answer question asks for standard terms or concepts (phase transition processes), which can be converted into a multiple-choice format by listing possible options and identifying the correct ones.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystallization; Vitrification; Phase separation", "B": "Recrystallization; Glass transition; Spinodal decomposition", "C": "Solidification; Polymorphic transformation; Eutectic reaction", "D": "Nucleation; Grain growth; Martensitic transformation" }, "correct_answer": "A", "explanation": "The correct answer is A because these three processes (crystallization, vitrification, phase separation) are the fundamental phase transitions that can occur during melt cooling. Option B uses similar-sounding but incorrect processes: recrystallization occurs in solids, glass transition is not a phase transition, and spinodal decomposition is a specific type of phase separation. Option C lists valid metallurgical processes but not the fundamental phase transitions from melt. Option D mixes nucleation (a mechanism) with grain growth (solid-state process) and martensitic transformation (solid-solid transition), creating a plausible but incorrect combination.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 778, "question": "During the growth of crystals, there must be the presence of undercooling", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（×表示错误），符合判断题的特征 | 知识层次: 题目考查晶体生长过程中过冷现象的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆晶体生长过程中过冷度的基本定义即可作答，无需深入理解或分析复杂概念。", "convertible": true, "correct_option": "×", "choice_question": "During the growth of crystals, there must be the presence of undercooling", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials will eventually crystallize given sufficient time at temperatures below their melting point.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because some amorphous materials, like certain glasses, are thermodynamically stable in their amorphous state and will not crystallize even over geological timescales. The statement contains an absolute claim ('all') that doesn't account for materials with extremely high kinetic barriers to crystallization or those that are thermodynamically favored to remain amorphous.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 760, "question": "In the orthorhombic crystal system, the (001) plane must be perpendicular to the (110) plane", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对正交晶系中晶面垂直关系的基本概念记忆和理解，属于晶体学基础知识的直接应用，不需要复杂的计算或分析。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅考察对正交晶系中晶面垂直关系的基础定义记忆，不需要理解或分析多个概念，解题步骤非常简单直接。", "convertible": true, "correct_option": "√", "choice_question": "In the orthorhombic crystal system, the (001) plane must be perpendicular to the (110) plane", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In the orthorhombic crystal system, the (001) plane must be perpendicular to the (110) plane", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "In the orthorhombic crystal system, the axes are mutually perpendicular (a ≠ b ≠ c, α = β = γ = 90°). The (001) plane is defined by the a and b axes, while the (110) plane is defined by the a and b axes at 45° to each. Due to the orthogonal nature of the system, these planes must be perpendicular. A common misconception might be that the angle between planes depends on the Miller indices alone without considering the crystal system's symmetry constraints.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1832, "question": "What is the migration of particles caused by intrinsic diffusion?", "answer": "Vacancies generated by intrinsic thermal defects", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释粒子迁移的原因，答案是以文字形式给出的解释性回答，不需要计算或选择，符合简答题的特征 | 知识层次: 题目考查对\"本征扩散\"这一基础概念的理解，需要记忆本征扩散是由本征热缺陷产生的空位迁移这一基本原理，属于材料科学中扩散机制的基础知识。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即\"本征扩散引起的粒子迁移\"的定义。正确选项直接对应基础概念，不需要解释或分析过程，属于最简单的定义性记忆题目。", "convertible": true, "correct_option": "Vacancies generated by intrinsic thermal defects", "choice_question": "What is the migration of particles caused by intrinsic diffusion?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Vacancies generated by intrinsic thermal defects", "B": "Interstitial atoms moving through crystal lattice", "C": "Grain boundary sliding under stress", "D": "Dislocation climb due to applied shear" }, "correct_answer": "A", "explanation": "The correct answer is A because intrinsic diffusion is fundamentally driven by vacancy mechanisms arising from thermal defects. Option B is a cognitive bias trap - while interstitial diffusion is real, it's not the primary mechanism for intrinsic diffusion. Option C exploits professional intuition by presenting a plausible but unrelated grain boundary phenomenon. Option D is a multi-level verification trap - dislocation climb does involve diffusion but is an extrinsic mechanism requiring stress.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4717, "question": "Determine the approximate density of a Ti-6Al-4V titanium alloy that has a composition of 90 wt% \\mathrm{Ti}, 6 wt% \\mathrm{Al}, and 4 wt% V.", "answer": "the approximate density of the ti-6al-4v titanium alloy is 4.38 \\mathrm{g/cm}^3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定钛合金的近似密度，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用密度计算公式，结合各成分的质量分数和密度进行简单计算，属于基本公式的直接套用和简单计算。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算Ti-6Al-4V钛合金的近似密度，只需应用简单的密度加权平均公式，无需复杂的推导或多步骤计算。正确选项直接给出了计算结果，考生只需确认计算过程是否正确即可。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "4.38 g/cm³", "choice_question": "What is the approximate density of a Ti-6Al-4V titanium alloy that has a composition of 90 wt% Ti, 6 wt% Al, and 4 wt% V?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.38 g/cm³", "B": "4.52 g/cm³", "C": "3.95 g/cm³", "D": "4.78 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer is A (4.38 g/cm³) because this value is calculated using the rule of mixtures for density, considering the weighted average of the densities of Ti (4.51 g/cm³), Al (2.70 g/cm³), and V (6.11 g/cm³). Option B (4.52 g/cm³) is a trap for those who incorrectly assume the density is closer to pure Ti due to its high weight percentage. Option C (3.95 g/cm³) exploits the misconception that adding lighter Al significantly reduces density. Option D (4.78 g/cm³) is designed to catch those who overestimate the impact of V's high density.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2050, "question": "What is dynamic undercooling?", "answer": "During crystal growth, a certain degree of undercooling in the liquid ahead of the liquid-solid interface is required to satisfy (dN/dt)F>(dN/dt)M. This undercooling is called dynamic undercooling (ΔTl=Tm−Ti), which is a necessary condition for crystal growth.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"dynamic undercooling\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征 | 知识层次: 题目考查动态过冷（dynamic undercooling）的基本定义和原理，属于基础概念的记忆和理解范畴，不涉及复杂的应用或分析。 | 难度: 在选择题中属于中等难度，需要理解动态过冷度的定义及其在晶体生长中的作用，但不需要进行复杂的比较分析或多概念整合。", "convertible": true, "correct_option": "During crystal growth, a certain degree of undercooling in the liquid ahead of the liquid-solid interface is required to satisfy (dN/dt)F>(dN/dt)M. This undercooling is called dynamic undercooling (ΔTl=Tm−Ti), which is a necessary condition for crystal growth.", "choice_question": "What is dynamic undercooling?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct option among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The undercooling required to maintain crystal growth when interface kinetics dominate over diffusion", "B": "The temperature difference between melting point and recalescence point during rapid solidification", "C": "The additional undercooling needed to overcome nucleation barrier in amorphous materials", "D": "The transient undercooling caused by rapid heat extraction in laser processing" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines dynamic undercooling as the undercooling needed at the solid-liquid interface when growth is controlled by interface kinetics (dN/dt)F>(dN/dt)M. Option B exploits confusion with recalescence phenomena in rapid solidification. Option C targets confusion with nucleation theory in glasses. Option D creates a plausible-sounding but incorrect association with rapid cooling processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4071, "question": "Select T / F for the following statement regarding copper & copper alloys: Copper is much more abundant in the earth's crust compared to iron or aluminum.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（T/F），且答案直接给出对错判断（F），符合判断题的特征 | 知识层次: 题目考查对铜、铁和铝在地壳中丰度的基本概念记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅涉及基础概念的正误判断，即铜在地壳中的丰度与铁或铝的比较。题目不需要复杂的分析或理解多个概念，只需记忆相关基本事实即可判断正误。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "F", "choice_question": "Select T / F for the following statement regarding copper & copper alloys: Copper is much more abundant in the earth's crust compared to iron or aluminum.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All copper alloys exhibit higher electrical conductivity than pure copper due to alloying effects.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because pure copper has the highest electrical conductivity among copper materials. Alloying elements generally disrupt the crystal lattice and reduce conductivity, though some specialized alloys may maintain relatively high conductivity for specific applications. A common misconception is that alloying always improves material properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 400, "question": "What are the characteristics of the modulated structure?", "answer": "The modulated structure exhibits a periodic pattern, with high dispersion, uniform distribution, and high connectivity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释调制结构的特征，答案提供了详细的文字描述和论述，符合简答题的特点。 | 知识层次: 题目考查对调制结构基本特征的理解和记忆，属于基础概念层次，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆（调制结构的特征），但正确选项包含了四个并列的特征描述（周期性图案、高分散性、均匀分布、高连通性），需要学生对调制结构有较全面的理解才能准确识别。这比单纯记忆单个特征（等级1）要求更高，但尚未达到需要分析复杂概念体系的等级3难度。", "convertible": true, "correct_option": "The modulated structure exhibits a periodic pattern, with high dispersion, uniform distribution, and high connectivity.", "choice_question": "Which of the following best describes the characteristics of the modulated structure?", "conversion_reason": "The answer is a standard description of the characteristics of the modulated structure, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The modulated structure exhibits a periodic pattern, with high dispersion, uniform distribution, and high connectivity", "B": "The modulated structure shows random atomic arrangements with localized strain fields and discontinuous interfaces", "C": "The modulated structure displays quasi-periodic ordering with alternating regions of high and low density", "D": "The modulated structure features aperiodic stacking faults with varying interplanar spacing and anisotropic properties" }, "correct_answer": "A", "explanation": "The correct answer A describes the essential characteristics of modulated structures which include periodicity, dispersion uniformity and connectivity. Option B incorrectly suggests randomness which contradicts the fundamental nature of modulated structures. Option C introduces quasi-periodicity which is a distinct phenomenon from true modulation. Option D describes stacking faults which are defects rather than intentional modulated structures. The distractors exploit common misconceptions about periodicity (B), quasi-crystals (C), and defect structures (D) that may appear plausible to AI systems without deep materials science training.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2648, "question": "It is known that pure titanium at 20°C is α-Ti (hcp structure), with lattice constants a=0.2951nm and c=0.4679nm. Calculate the interplanar spacing of the (112) plane.", "answer": "For the hcp structure, when h+2k=3n (n=0,1,2,3...), and l is an odd number, there is an additional plane. d_(112)=1/√[(4/3)((h²+hk+k²)/a²)+(l/c)²]=1/√[(4/3)((1²+1×1+1²)/0.2951²)+(2/0.4679)²]=0.1248nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解(112)晶面的面间距，答案给出了具体的计算过程和结果。 | 知识层次: 题目需要应用hcp结构的晶面间距计算公式，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要掌握hcp结构晶面间距的计算公式，理解晶面指数的含义，并能正确代入数值进行多步骤计算。题目涉及的概念和计算步骤较为复杂，但选项提供了明确的解题路径，降低了部分难度。", "convertible": true, "correct_option": "0.1248nm", "choice_question": "It is known that pure titanium at 20°C is α-Ti (hcp structure), with lattice constants a=0.2951nm and c=0.4679nm. The interplanar spacing of the (112) plane is:", "conversion_reason": "The calculation question has a specific numerical answer, which can be converted into a multiple-choice format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1248nm", "B": "0.1362nm", "C": "0.1483nm", "D": "0.1576nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.1248nm) calculated using the hcp interplanar spacing formula for (112) planes. Option B (0.1362nm) is a common mistake from incorrectly using the cubic crystal formula. Option C (0.1483nm) results from forgetting to square the Miller indices in the denominator. Option D (0.1576nm) comes from misapplying the c/a ratio calculation. Advanced AIs may fail by: 1) Applying cubic crystal formulas to hcp (B), 2) Making algebraic errors in complex hcp calculations (C), or 3) Confusing interplanar spacing with atomic layer spacing (D).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2752, "question": "Cesium chloride (CsCl) has an ordered body-centered cubic structure, which belongs to (A) body-centered cubic lattice (B) face-centered cubic lattice (C) simple cubic lattice", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（A、B、C）中选择正确答案 | 知识层次: 题目考查对晶体结构分类的基本概念记忆，只需识别CsCl的晶体结构类型即可，无需复杂分析或计算。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（CsCl的晶体结构类型），但需要考生理解并区分不同的立方晶格类型（体心立方、面心立方和简单立方）。正确选项（C）需要考生能够辨析CsCl的有序体心立方结构实际上属于简单立方格子，而不是直接选择体心立方格子（A）。这种辨析需要一定的概念理解和简单分析能力，因此难度等级为2。", "convertible": true, "correct_option": "C", "choice_question": "Cesium chloride (CsCl) has an ordered body-centered cubic structure, which belongs to", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The coordination number of Cs+ is 8, forming a true body-centered cubic lattice", "B": "The structure is face-centered cubic with 12 nearest neighbors for Cs+", "C": "It's a simple cubic lattice where each ion has 6 nearest neighbors", "D": "The structure is hexagonal close-packed with 12 nearest neighbors" }, "correct_answer": "C", "explanation": "The correct answer is C because CsCl's ordered BCC structure is actually based on two interpenetrating simple cubic lattices (one for Cs+ and one for Cl-), where each ion has 6 nearest neighbors of the opposite type. Option A is a cognitive bias trap - while the coordination number is 8, it's not a true BCC lattice but rather two SC lattices. Option B exploits the FCC intuition trap, as FCC is another common close-packed structure. Option D uses the HCP analogy fallacy, another common close-packed structure that doesn't apply here.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2135, "question": "When diffusion occurs via the vacancy mechanism, each atomic jump corresponds to a reverse jump of the vacancy without creating a new vacancy, yet the diffusion activation energy includes the vacancy formation energy. Is this statement correct? Please provide the correct explanation.", "answer": "This statement is incorrect. The macroscopic diffusion flux in solids is not the result of directional jumps of individual atoms, nor is the diffusion activation energy the energy barrier that must be overcome for each jump during atomic migration. Atomic jumps in solids are random in nature, and the diffusion flux is the macroscopic manifestation of the statistical outcome of random jumps of diffusing particles (such as atoms or ions) in the solid. When diffusion in a crystal occurs via the vacancy mechanism, any atomic jump between two equilibrium positions must simultaneously satisfy two conditions: (1) The atom must possess energy higher than a certain critical value $\\Delta G_{\\mathrm{f}}$, i.e., the activation energy for atomic jumps, to overcome the resistance hindering the jump; (2) A vacancy must exist at the adjacent equilibrium position of the atom. According to statistical thermodynamics theory, at a given temperature $T$, the probability $P_{\\textrm{f}}$ that any atom in the crystal has energy higher than $\\Delta G_{\\mathrm{f}}$, i.e., the atomic percentage of atoms with energy exceeding $\\Delta G_{\\mathrm{f}}$, is $$P_{\\mathrm{f}}=\\exp\\Bigl(\\frac{-\\Delta G_{\\mathrm{f}}}{k T}\\Bigr)$$ The equilibrium vacancy concentration $c_{\\mathrm{v}}$ in the crystal, i.e., the probability $P_{\\mathrm{~v~}}$ of a vacancy appearing at any atomic equilibrium position, is $$P_{\\mathrm{v}}=\\exp\\Bigl(\\frac{-\\Delta G_{\\mathrm{v}}}{k T}\\Bigr)$$ Clearly, the probability $P$ that an atom in the crystal undergoes a jump at any given moment is $$P=P_{\\mathrm{f}}P_{\\mathrm{v}}=\\exp\\Bigl(-\\frac{\\Delta G_{\\mathrm{f}}+\\Delta G_{\\mathrm{v}}}{k T}\\Bigr)=\\exp\\Bigl(-\\frac{Q}{R T}\\Bigr)$$ Here, $P$ also equals the atomic percentage of atoms undergoing jumps at that moment. The term $Q=\\Delta G_{\\mathrm{f}}+\\Delta G_{\\mathrm{v}}$ represents the diffusion activation energy for the vacancy diffusion mechanism.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目首先要求判断一个陈述是否正确（\"Is this statement correct?\"），然后需要提供正确的解释。这符合判断题的特征，即先判断对错，再解释原因。答案中明确指出了陈述的错误，并提供了详细的解释来支持判断。 | 知识层次: 题目不仅要求判断陈述的对错，还需要深入理解扩散激活能的组成和空位扩散机制的统计热力学基础。解答过程涉及多个概念的关联（如空位形成能、跳跃激活能、扩散通量的统计本质）和综合分析（概率计算、统计热力学理论的应用），思维过程较为深入和复杂。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "This statement is incorrect. The macroscopic diffusion flux in solids is not the result of directional jumps of individual atoms, nor is the diffusion activation energy the energy barrier that must be overcome for each jump during atomic migration. Atomic jumps in solids are random in nature, and the diffusion flux is the macroscopic manifestation of the statistical outcome of random jumps of diffusing particles (such as atoms or ions) in the solid. When diffusion in a crystal occurs via the vacancy mechanism, any atomic jump between two equilibrium positions must simultaneously satisfy two conditions: (1) The atom must possess energy higher than a certain critical value $\\Delta G_{\\mathrm{f}}$, i.e., the activation energy for atomic jumps, to overcome the resistance hindering the jump; (2) A vacancy must exist at the adjacent equilibrium position of the atom. According to statistical thermodynamics theory, at a given temperature $T$, the probability $P_{\\textrm{f}}$ that any atom in the crystal has energy higher than $\\Delta G_{\\mathrm{f}}$, i.e., the atomic percentage of atoms with energy exceeding $\\Delta G_{\\mathrm{f}}$, is $$P_{\\mathrm{f}}=\\exp\\Bigl(\\frac{-\\Delta G_{\\mathrm{f}}}{k T}\\Bigr)$$ The equilibrium vacancy concentration $c_{\\mathrm{v}}$ in the crystal, i.e., the probability $P_{\\mathrm{~v~}}$ of a vacancy appearing at any atomic equilibrium position, is $$P_{\\mathrm{v}}=\\exp\\Bigl(\\frac{-\\Delta G_{\\mathrm{v}}}{k T}\\Bigr)$$ Clearly, the probability $P$ that an atom in the crystal undergoes a jump at any given moment is $$P=P_{\\mathrm{f}}P_{\\mathrm{v}}=\\exp\\Bigl(-\\frac{\\Delta G_{\\mathrm{f}}+\\Delta G_{\\mathrm{v}}}{k T}\\Bigr)=\\exp\\Bigl(-\\frac{Q}{R T}\\Bigr)$$ Here, $P$ also equals the atomic percentage of atoms undergoing jumps at that moment. The term $Q=\\Delta G_{\\mathrm{f}}+\\Delta G_{\\mathrm{v}}$ represents the diffusion activation energy for the vacancy diffusion mechanism.", "choice_question": "When diffusion occurs via the vacancy mechanism, each atomic jump corresponds to a reverse jump of the vacancy without creating a new vacancy, yet the diffusion activation energy includes the vacancy formation energy. Is this statement correct? Please provide the correct explanation.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "When diffusion occurs via the vacancy mechanism, each atomic jump corresponds to a reverse jump of the vacancy without creating a new vacancy, yet the diffusion activation energy includes the vacancy formation energy.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is incorrect. The macroscopic diffusion flux in solids is not the result of directional jumps of individual atoms, nor is the diffusion activation energy the energy barrier that must be overcome for each jump during atomic migration. Atomic jumps in solids are random in nature, and the diffusion flux is the macroscopic manifestation of the statistical outcome of random jumps of diffusing particles (such as atoms or ions) in the solid. When diffusion in a crystal occurs via the vacancy mechanism, any atomic jump between two equilibrium positions must simultaneously satisfy two conditions: (1) The atom must possess energy higher than a certain critical value to overcome the resistance hindering the jump; (2) A vacancy must exist at the adjacent equilibrium position of the atom. The diffusion activation energy for the vacancy mechanism includes both the energy barrier for atomic jumps and the vacancy formation energy, reflecting the statistical probability of these two conditions being met simultaneously.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2847, "question": "Calculate the volume fraction φ_Fe3C of the Fe3C phase in 40 steel, given the mass fraction of carbon w_c=0.004.", "answer": "φ_Fe3C = 0.004 / 0.0667 = 0.06", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算Fe3C相的体积分数），并给出了具体的计算步骤和公式应用（φ_Fe3C = w_c / 0.0667），最终得出数值结果（0.06）。这符合计算题的特征。 | 知识层次: 题目考查基本公式应用和简单计算，仅需将给定的质量分数代入公式进行一步除法运算即可得到结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算（φ_Fe3C = w_c / 0.0667），无需额外的概念理解或步骤组合。题目提供所有必要参数，且计算过程简单直接，属于最基础的公式应用层级。", "convertible": true, "correct_option": "0.06", "choice_question": "Calculate the volume fraction φ_Fe3C of the Fe3C phase in 40 steel, given the mass fraction of carbon w_c=0.004.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.06", "B": "0.12", "C": "0.03", "D": "0.09" }, "correct_answer": "A", "explanation": "The correct answer is 0.06, calculated using the mass fraction of carbon and the densities of Fe and Fe3C. Option B (0.12) is a common error from doubling the correct value due to misinterpreting the carbon content. Option C (0.03) results from incorrectly halving the correct value, a mistake in proportion calculation. Option D (0.09) is designed to exploit rounding errors or incorrect density assumptions in the calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4379, "question": "Briefly explain why the hardness of tempered martensite diminishes with tempering time at constant temperature.", "answer": "The hardness of tempered martensite diminishes with tempering time at constant temperature because the microstructure consists of small sphere-like particles of cementite embedded within a ferrite matrix. As tempering time increases, the cementite particles grow, which reduces the ferrite-cementite phase boundary area. Since these phase boundaries act as barriers to dislocation motion, the reduction in phase boundary area leads to a decrease in hardness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释一个现象，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释回火马氏体硬度随回火时间降低的微观机理，涉及相变、析出相长大、位错运动障碍等多重概念的综合分析和推理，需要深入理解材料微观结构与性能的关系。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解回火马氏体的微观结构变化（渗碳体颗粒在铁素体基体中的分布），还需要掌握相界面对位错运动的阻碍机制，并能分析时间变量对微观结构演化的影响。这需要考生具备将材料科学基础理论（相变、位错理论）与工程实践（回火工艺）相结合的复杂分析能力，属于典型的机理深度解释与复杂现象全面分析题型。", "convertible": true, "correct_option": "The hardness of tempered martensite diminishes with tempering time at constant temperature because the microstructure consists of small sphere-like particles of cementite embedded within a ferrite matrix. As tempering time increases, the cementite particles grow, which reduces the ferrite-cementite phase boundary area. Since these phase boundaries act as barriers to dislocation motion, the reduction in phase boundary area leads to a decrease in hardness.", "choice_question": "Why does the hardness of tempered martensite diminish with tempering time at constant temperature?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The growth of cementite particles reduces phase boundary area, decreasing dislocation barrier effectiveness", "B": "Increased carbon diffusion leads to precipitation hardening reversal at prolonged tempering times", "C": "Dislocation density decreases due to recrystallization of the ferrite matrix", "D": "The tetragonality of martensite gradually disappears, reducing lattice distortion hardening" }, "correct_answer": "A", "explanation": "The correct answer is A because the key mechanism is the reduction of phase boundary area as cementite particles coarsen, which decreases barriers to dislocation motion. Option B is a cognitive bias trap - while carbon diffusion is involved, the reversal of precipitation hardening is incorrect. Option C exploits recrystallization intuition but ferrite doesn't recrystallize at typical tempering temperatures. Option D uses a real phenomenon (tetragonality loss) but this occurs early in tempering and isn't the primary reason for hardness decrease with prolonged time.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1584, "question": "1. The macroscopic symmetry elements of crystals include (1), (2), (3), (4), and (5)", "answer": "(1) center of symmetry; (2) axis of symmetry; (3) plane of symmetry; (4) rotoinversion axis; (5) rotoreflection axis", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举晶体的宏观对称元素，答案需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查对晶体宏观对称元素的基本概念的记忆和理解，不需要复杂的应用或分析，只需列举出对称元素的名称即可。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目仅要求记忆晶体宏观对称元素的基本分类，无需进行概念解释或复杂体系阐述。正确选项直接对应基础概念记忆的知识层次，解题步骤简单，仅需识别和匹配对称元素的名称即可。", "convertible": true, "correct_option": "(1) center of symmetry; (2) axis of symmetry; (3) plane of symmetry; (4) rotoinversion axis; (5) rotoreflection axis", "choice_question": "The macroscopic symmetry elements of crystals include:", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。题目可以改写为选择形式，正确选项为原答案。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "center of symmetry, axis of symmetry, plane of symmetry, rotoinversion axis, rotoreflection axis", "B": "center of symmetry, axis of symmetry, plane of symmetry, screw axis, glide plane", "C": "center of symmetry, axis of symmetry, plane of symmetry, Burgers vector, stacking fault", "D": "center of symmetry, axis of symmetry, plane of symmetry, dislocation line, twin boundary" }, "correct_answer": "A", "explanation": "The correct answer A lists all five macroscopic symmetry elements of crystals. Option B incorrectly includes microscopic symmetry elements (screw axis and glide plane). Option C mixes symmetry elements with crystal defects (Burgers vector and stacking fault). Option D also mixes symmetry elements with crystal defects (dislocation line and twin boundary). Advanced AI models might confuse macroscopic and microscopic symmetry elements (trap in B) or mistakenly include crystal defects (traps in C and D) due to their strong association with crystal structure analysis.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1503, "question": "How do the strength and hardness of a metal with finer grains compare to the same metal with coarser grains", "answer": "Higher", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释金属晶粒尺寸对强度和硬度的影响，需要文字论述而非简单选择或判断 | 知识层次: 题目需要理解晶粒尺寸对金属强度和硬度的影响机制，并能够将Hall-Petch关系等概念与实际材料性能关联起来进行分析。虽然不涉及复杂计算，但需要多步概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解金属晶粒尺寸对强度和硬度的影响这一概念，并进行比较分析。虽然题目没有涉及多步计算，但要求考生能够关联晶粒细化与力学性能之间的关系，属于中等应用层次的知识点。", "convertible": true, "correct_option": "Higher", "choice_question": "How do the strength and hardness of a metal with finer grains compare to the same metal with coarser grains?", "conversion_reason": "The answer is a standard term that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Higher due to increased grain boundary strengthening", "B": "Lower because finer grains reduce dislocation density", "C": "Equal since grain size does not affect bulk properties", "D": "Higher for strength but lower for hardness due to different deformation mechanisms" }, "correct_answer": "A", "explanation": "Correct answer is A because finer grains increase strength and hardness through grain boundary strengthening (Hall-Petch effect). B exploits the misconception that finer grains reduce dislocation density (actually increases). C uses the false intuition that bulk properties are size-independent. D creates a false dichotomy between strength and hardness responses.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1394, "question": "Calculate the coordination number of the cation in the compound CaF2, given r(Ca2+)=0.106nm and r(F-)=0.133nm", "answer": "8", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的离子半径数值计算CaF2中阳离子的配位数，涉及数值计算和公式应用，答案是一个具体的数值结果。 | 知识层次: 题目要求应用离子半径比公式计算配位数，属于基本公式的直接套用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目提供了离子半径数据，并直接要求计算配位数，只需应用简单的半径比公式即可得出答案。无需多个公式组合或复杂分析，属于最基础的计算类型。", "convertible": true, "correct_option": "8", "choice_question": "What is the coordination number of the cation in the compound CaF2, given r(Ca2+)=0.106nm and r(F-)=0.133nm?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项B", "B": "选项D", "C": "选项C", "D": "8" }, "correct_answer": "D", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 3588, "question": "Determine the crystal structure for a metal with a0=0.42906 nm, r=0.1858 nm and one atom per lattice point.", "answer": "bcc", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算和解释确定晶体的结构类型，答案需要基于给定的参数（a0和r）进行推导，并给出具体的晶体结构类型（如bcc），这属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求根据给定的晶格常数和原子半径确定晶体结构，这需要应用基本的晶体几何关系公式进行计算和判断。虽然涉及一定的计算步骤，但属于直接套用公式和基本概念的应用，不需要复杂的分析或综合。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需套用基本公式（如原子半径与晶格常数的关系）进行简单计算即可确定晶体结构类型。解题步骤直接且无需复杂分析，符合等级2的简单应用过程描述标准。", "convertible": true, "correct_option": "bcc", "choice_question": "Determine the crystal structure for a metal with a0=0.42906 nm, r=0.1858 nm and one atom per lattice point.", "conversion_reason": "The answer is a standard term (bcc) and the question can be converted to a multiple-choice format by providing options such as fcc, bcc, hcp, etc.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "bcc", "B": "fcc", "C": "hcp", "D": "simple cubic" }, "correct_answer": "A", "explanation": "The correct answer is bcc because the given atomic radius (r=0.1858 nm) and lattice parameter (a0=0.42906 nm) satisfy the bcc relationship where 4r = √3a0 (calculated as 4*0.1858 ≈ √3*0.42906). Option B (fcc) is a strong distractor because fcc is a common close-packed structure that AI might default to, but it would require √2a0 = 4r which doesn't hold here. Option C (hcp) exploits the tendency to assume close-packing when seeing fractional atomic radii, while ignoring the given lattice parameter. Option D (simple cubic) is a subtle trap because the radius is close to a0/2, but this would leave insufficient space between atoms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1579, "question": "What type of void does the Cs+ ion occupy in CsCl crystal?", "answer": "Cubic", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字回答Cs+离子在CsCl晶体中占据的空隙类型，答案\"Cubic\"是一个简短的描述性回答，不需要选择或判断，也不需要计算。 | 知识层次: 题目考查对CsCl晶体结构中Cs+离子占据的空隙类型的基本概念记忆，属于晶体结构分类的基础知识，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目仅考察对CsCl晶体中Cs+离子占据空隙类型的基础记忆，属于基本定义简答级别。学生只需记住CsCl晶体结构中阳离子占据立方空隙这一基本事实即可作答，无需进行概念解释或复杂分析。", "convertible": true, "correct_option": "Cubic", "choice_question": "What type of void does the Cs+ ion occupy in CsCl crystal?", "conversion_reason": "The answer is a standard term (Cubic), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cubic", "B": "Octahedral", "C": "Tetrahedral", "D": "Trigonal bipyramidal" }, "correct_answer": "A", "explanation": "The Cs+ ion occupies the cubic void in CsCl crystal structure, which is a simple cubic arrangement of Cl- ions with Cs+ in the center. The key confusion here is that many AI models might default to octahedral (B) or tetrahedral (C) voids because these are more commonly discussed in typical crystal structures like FCC or HCP. The trigonal bipyramidal (D) option is a rare geometry that sounds plausible but doesn't apply here. This question exploits the AI's tendency to generalize from more common crystal structure examples rather than recognizing the unique simple cubic packing in CsCl.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1609, "question": "What is a perfect dislocation?", "answer": "A dislocation whose Burgers vector equals a lattice vector is called a perfect dislocation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"perfect dislocation\"进行定义和解释，答案以文字形式给出，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查基本概念的记忆和理解，即完美位错的定义，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类，仅需识别和回忆\"perfect dislocation\"的定义即可作答。题目直接给出了定义性描述，不需要任何解释或推理过程，符合等级1\"基本定义简答\"的标准。在选择题难度谱系中，这是最基础级别的题目类型。", "convertible": true, "correct_option": "A dislocation whose Burgers vector equals a lattice vector", "choice_question": "Which of the following describes a perfect dislocation?", "conversion_reason": "The answer is a standard definition that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A dislocation whose Burgers vector equals a lattice vector", "B": "A dislocation that maintains perfect crystallinity along its core", "C": "A dislocation with zero elastic strain energy in its stress field", "D": "A dislocation that can glide without leaving any defects behind" }, "correct_answer": "A", "explanation": "The correct answer is A because a perfect dislocation is defined by its Burgers vector being equal to a translation vector of the crystal lattice. Option B is a cognitive bias trap - while dislocations distort the lattice, 'perfect crystallinity' is impossible at the core. Option C exploits intuition about 'perfect' implying zero energy, but all dislocations have associated strain energy. Option D is a professional intuition trap - while perfect dislocations can glide, they always leave behind plastic deformation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1991, "question": "Given the Burgers vector b=0.25 nm, if the misorientation angle θ of the symmetric tilt grain boundary is 1°, calculate the distance between dislocations at the grain boundary.", "answer": "When θ=1°, D=14 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的Burgers向量和错向角计算晶界位错间距，需要应用公式进行数值计算，答案也是具体的数值结果。 | 知识层次: 题目要求应用基本公式（Burgers vector与位错间距的关系公式）进行简单计算，无需多步推理或综合分析，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目明确给出了Burgers向量和晶界错向角，只需要应用基本公式D = b/θ（需注意角度转换为弧度）即可直接计算出位错间距。解题步骤简单，无需复杂推导或多公式组合，属于最基础的应用题类型。", "convertible": true, "correct_option": "14 nm", "choice_question": "Given the Burgers vector b=0.25 nm, if the misorientation angle θ of the symmetric tilt grain boundary is 1°, what is the distance between dislocations at the grain boundary?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "14 nm", "B": "0.25 nm", "C": "1.43 nm", "D": "25 nm" }, "correct_answer": "A", "explanation": "正确答案A通过公式D=b/θ计算得出，其中θ需转换为弧度。干扰项B直接使用Burgers向量值，利用第一印象直觉陷阱。干扰项C是错误使用角度转换系数(57.3)的结果，属于认知偏差干扰。干扰项D通过错误公式D=b×θ产生，利用单位混淆策略。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 640, "question": "Twinning", "answer": "Twinning: An important mode of plastic deformation in crystals. Under shear stress, one part of the crystal undergoes uniform shear relative to another part along specific crystallographic planes and directions, resulting in different orientations of adjacent crystal regions that are mirror-symmetrical across the twinning plane (twin boundary).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Twinning\"这一概念进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查的是孪晶变形的基本概念和原理，属于对晶体塑性变形模式的定义和基本机制的记忆和理解，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于概念解释和描述的难度等级。虽然题目涉及晶体塑性变形的基本原理和具体机制，但正确选项已经提供了较为详细的解释，包括孪生的定义、发生条件（剪切应力）、具体过程（沿特定晶面和方向的均匀剪切）以及结果（相邻晶体区域的镜像对称取向）。这些信息足以让具备基础材料科学知识的考生识别出正确答案，无需进行复杂的分析或比较多个概念。因此，该题目在选择题型中属于中等难度（等级2）。", "convertible": true, "correct_option": "Twinning: An important mode of plastic deformation in crystals. Under shear stress, one part of the crystal undergoes uniform shear relative to another part along specific crystallographic planes and directions, resulting in different orientations of adjacent crystal regions that are mirror-symmetrical across the twinning plane (twin boundary).", "choice_question": "下列关于Twinning的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Twinning: An important mode of plastic deformation in crystals. Under shear stress, one part of the crystal undergoes uniform shear relative to another part along specific crystallographic planes and directions, resulting in different orientations of adjacent crystal regions that are mirror-symmetrical across the twinning plane (twin boundary).", "B": "Twinning: A diffusion-controlled phase transformation process where atoms rearrange into a mirror-symmetric configuration through long-range atomic migration, similar to martensitic transformation but occurring at higher temperatures.", "C": "Twinning: A purely elastic deformation mechanism where the crystal lattice temporarily distorts under stress but returns to its original configuration upon stress removal, with the twin boundary acting as a reversible elastic discontinuity.", "D": "Twinning: A defect annihilation process where dislocations of opposite signs combine to form perfect crystal regions, with the twin boundary representing the transition zone between the original and 'healed' crystal regions." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes twinning as a plastic deformation mechanism involving shear-induced mirror symmetry. Option B incorrectly presents twinning as diffusion-controlled (it's actually shear-driven). Option C falsely characterizes it as elastic (it's plastic/permanent). Option D wrongly associates twinning with defect annihilation (it's a deformation mechanism, not a healing process). These distractors exploit common misconceptions about deformation mechanisms, phase transformations, and defect interactions in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4043, "question": "Which type of charge carrier will be introduced into a semiconductor by the presence of an acceptor impurity?(a) Electron(b) Hole", "answer": "The presence of an acceptor impurity introduces holes into a semiconductor.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从两个选项(a)和(b)中选择正确答案，符合选择题的特征 | 知识层次: 题目考查半导体中受主杂质引入载流子的基本概念，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即\"受主杂质引入空穴\"这一简单事实的识别。不需要任何理解或分析过程，属于直接记忆性知识，符合等级1的简单概念识别标准。", "convertible": true, "correct_option": "Hole", "choice_question": "Which type of charge carrier will be introduced into a semiconductor by the presence of an acceptor impurity?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly identifies the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hole", "B": "Electron", "C": "Both holes and electrons", "D": "Neither, it creates a neutral defect state" }, "correct_answer": "A", "explanation": "The correct answer is A (Hole) because acceptor impurities create additional holes in the valence band by accepting electrons from the valence band. Option B (Electron) is a cognitive bias trap - it exploits the common association between doping and increased conductivity, but confuses donor and acceptor behavior. Option C (Both) is a multi-level verification trap that seems plausible if considering thermal generation of carriers, but ignores the dominant effect of the impurity. Option D (Neither) is a professional intuition trap that mimics deep-level defect behavior, but is incorrect for shallow acceptors in semiconductors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1807, "question": "In the spinel (MgAl2O4) structure, O2- forms a cubic close packing, and Mg2+ ions fill a. 1/2 of the tetrahedral voids b. 1/2 of the octahedral voids c. 1/8 of the tetrahedral voids d. 1/8 of the octahedral voids", "answer": "c", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项a、b、c、d中选择正确答案 | 知识层次: 题目考查对尖晶石结构中离子填充位置的基础概念记忆，属于对晶体结构基本知识的直接应用，无需复杂分析或计算。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（spinel结构中离子的填充情况），但需要考生对立方紧密堆积中的四面体和八面体空隙有清晰的理解，并能区分不同离子填充的具体比例。这比单纯记忆定义（等级1）要求更高，但尚未达到需要复杂概念区分或深度理解的程度（等级3）。", "convertible": true, "correct_option": "c. 1/8 of the tetrahedral voids", "choice_question": "In the spinel (MgAl2O4) structure, O2- forms a cubic close packing, and Mg2+ ions fill", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship predicts increased yield strength with decreasing grain size due to dislocation pile-up at grain boundaries", "B": "The Hall-Petch relationship becomes invalid when grain size exceeds 100 nm due to the transition to dislocation-free deformation", "C": "The inverse Hall-Petch effect occurs below 10 nm grain size because grain boundary sliding becomes the dominant deformation mechanism", "D": "The Hall-Petch coefficient (k) is a universal constant for all metallic materials, approximately 0.7 MPa·m^1/2" }, "correct_answer": "A", "explanation": "Option A is correct as it accurately describes the classic Hall-Petch mechanism. Option B is a cognitive bias trap - while Hall-Petch does break down at nanoscale, the 100 nm threshold is arbitrary. Option C exploits intuitive but incorrect scaling assumptions about deformation mechanisms. Option D uses a plausible-looking numerical value but falsely suggests universality of the coefficient.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4305, "question": "Give the approximate temperature at which creep deformation becomes an important consideration for copper.", "answer": "for cu: 270 degrees c (518 degrees f)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从选项中选择或判断对错，也不需要复杂的计算过程。答案是一个简短的具体数值，属于简答题类型。 | 知识层次: 题目主要考查对铜材料蠕变温度这一特定数值的记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用过程。 | 难度: 在选择题型中，此题仅需记忆铜的蠕变温度这一具体数值，属于基础概念记忆层面的简单问题。不需要解释或分析概念，只需准确回忆特定知识点即可作答。", "convertible": true, "correct_option": "270 degrees C (518 degrees F)", "choice_question": "At approximately what temperature does creep deformation become an important consideration for copper?", "conversion_reason": "The answer is a specific temperature value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "270°C (518°F)", "B": "150°C (302°F)", "C": "400°C (752°F)", "D": "0.4 x melting temperature (340°C)" }, "correct_answer": "A", "explanation": "The correct answer is A because creep becomes significant for copper at approximately 0.3-0.4 of its absolute melting temperature (1083°C), which corresponds to 270°C. Option B is a cognitive bias trap using a common misconception about creep onset temperatures. Option C exploits professional intuition by suggesting a temperature that would be correct for some high-temperature alloys but is too high for copper. Option D is a multi-level verification trap that uses a correct general rule (0.4Tm) but applies it incorrectly to absolute rather than Kelvin scale.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2472, "question": "What is the time t required for spinodal decomposition to occur over a diffusion distance of λ_m/2=50 nm (with λ_m=100 nm) at 550K, given the interdiffusion coefficient D=-2.4×10^-18 m²/s?", "answer": "The time t required is calculated as t = (λ_m/2)² / (6D) = (50×10^-9)² / (6 * 2.4×10^-18) s = 173.6 s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和数值进行具体计算，最终得出一个数值结果。解答过程涉及公式应用和数值代入，符合计算题的特征。 | 知识层次: 题目主要考查基本公式的直接应用和简单计算，涉及将已知数值代入公式求解时间，不需要多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目仅需要直接套用一个基本公式进行计算，即t = (λ_m/2)² / (6D)。解题步骤简单，无需多个公式组合或复杂的概念理解，属于单一公式直接计算的难度等级。", "convertible": true, "correct_option": "173.6 s", "choice_question": "What is the time t required for spinodal decomposition to occur over a diffusion distance of λ_m/2=50 nm (with λ_m=100 nm) at 550K, given the interdiffusion coefficient D=-2.4×10^-18 m²/s?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "173.6 s", "B": "86.8 s", "C": "347.2 s", "D": "1.04×10^3 s" }, "correct_answer": "A", "explanation": "Correct answer is A (173.6 s) calculated using t=(λ_m/2)^2/(4D). B (86.8 s) is half the correct time, exploiting common factor-of-2 errors in diffusion calculations. C (347.2 s) doubles the correct time, targeting sign confusion in negative diffusion coefficients. D (1.04×10^3 s) uses incorrect unit conversion (nm to m without squaring), appealing to dimensional analysis intuition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2139, "question": "Why is the carburizing temperature for steel parts generally chosen to be in the γ phase region?", "answer": "Because the maximum carbon solubility (mass fraction) in α-Fe is only 0.0218%. For steel with a carbon mass fraction greater than 0.0218%, the carbon concentration gradient in the part during carburizing is zero, making carburizing impossible. Even for pure iron, carburizing in the α phase region results in a very small concentration gradient in the iron, and a high carbon layer cannot be obtained on the surface. Additionally, due to the low temperature, the diffusion coefficient is also very small, making the carburizing process extremely slow and practically meaningless. The carbon solubility in γ-Fe is high, allowing a higher carbon concentration gradient on the surface during carburizing, which facilitates the carburizing process.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么钢件的渗碳温度通常选择在γ相区，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要解释为什么钢的渗碳温度选择在γ相区，涉及碳在α-Fe和γ-Fe中的溶解度差异、浓度梯度、扩散系数等多个概念的综合分析，以及渗碳过程的机理解释。这需要深入理解相图、扩散原理和工艺参数选择之间的关系，属于复杂分析和推理的范畴。 | 难度: 在选择题型内，该题目属于最高难度等级。题目不仅要求考生掌握γ相区和α相区碳溶解度的基本概念，还需要深入理解碳浓度梯度、扩散系数等复杂机理。正确选项涉及多个知识点的综合运用和推理分析，包括碳溶解度差异、浓度梯度对渗碳过程的影响、温度对扩散系数的作用等。此外，题目要求考生将这些因素整合起来，全面分析为何γ相区更适合渗碳工艺，这超出了单纯记忆的范畴，属于复杂现象的全面分析层次。在选择题型中，这种需要多维度推理和机理深度解释的题目属于最高难度级别。", "convertible": true, "correct_option": "Because the maximum carbon solubility (mass fraction) in α-Fe is only 0.0218%. For steel with a carbon mass fraction greater than 0.0218%, the carbon concentration gradient in the part during carburizing is zero, making carburizing impossible. Even for pure iron, carburizing in the α phase region results in a very small concentration gradient in the iron, and a high carbon layer cannot be obtained on the surface. Additionally, due to the low temperature, the diffusion coefficient is also very small, making the carburizing process extremely slow and practically meaningless. The carbon solubility in γ-Fe is high, allowing a higher carbon concentration gradient on the surface during carburizing, which facilitates the carburizing process.", "choice_question": "Why is the carburizing temperature for steel parts generally chosen to be in the γ phase region?", "conversion_reason": "The answer is a detailed explanation that can be directly used as a correct option in a multiple-choice question. The question can be reformulated to present this explanation as one of the choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because γ-Fe has higher carbon solubility and faster diffusion rates, enabling effective surface carbon enrichment", "B": "To avoid the formation of brittle cementite (Fe3C) which occurs predominantly in the α phase region", "C": "Because the γ phase has lower thermal conductivity, allowing better heat concentration at the surface", "D": "To take advantage of the paramagnetic properties of γ-Fe which enhance carbon absorption" }, "correct_answer": "A", "explanation": "The correct answer is A because γ-Fe's face-centered cubic structure allows higher carbon solubility (up to 2.14%) compared to α-Fe's body-centered cubic structure (0.0218%), and the higher temperature increases diffusion rates. Option B is incorrect because cementite formation is not avoided in carburizing - it's actually desired in the case layer. Option C exploits thermal property confusion but conductivity is irrelevant to carburizing. Option D uses a true but irrelevant property (γ-Fe's paramagnetism) that doesn't affect carburizing kinetics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2027, "question": "An organic compound has the composition ${w_{\\mathrm{C}}=62.1/10^{-2}}$, ${w_{\\mathrm{H}}}=10.3/1\\\\time10^{-2}$, $\\\\varpi_{0}=27.6/10^{-2}$. Try to write the possible name of the compound.", "answer": "\\\\mathrm{{C}:\\\\mathrm{{H}:\\\\mathrm{{O}=\\\\frac{62.\\\\mathrm{{1}}}{12.\\\\mathrm{{,011}}}:\\\\frac{10.\\\\mathrm{{3}}}{1.\\\\mathrm{{007}\\\\mathrm{{97}}}}:\\\\frac{27.6}{15.\\\\mathrm{{9994}}}=5.2:10.2:1.7\\\\approx3:6:10.4:1.7\\\\approx3:6:1.74:\\\\mathrm{{8}.\\\\mathrm{{1}:\\\\mathrm{{7}}}}}}} Therefore, the possible compound is $\\\\mathrm{CH}_{3}\\\\mathrm{COCH}_{3}$ (acetone).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求根据给定的元素组成比例推导出可能的有机化合物名称，并给出详细的推导过程。答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目要求根据给定的元素组成比例计算并推断可能的有机化合物名称，主要涉及基本的化学计量计算和简单的分子式推导，属于基本公式应用和直接套用的范畴。虽然需要一定的计算步骤，但整体思维过程较为直接，不涉及复杂的概念关联或综合分析。 | 难度: 在选择题型中，该题目属于简单应用难度。题目要求根据给定的元素组成比例计算并推断可能的有机化合物名称。解题步骤包括基本的化学计量计算和简单的比例转换，最终直接套用常见有机化合物的分子式（丙酮）。选择题型中，这种题目仅需基本公式应用和简单计算，无需复杂的分析或推理过程，因此难度较低。", "convertible": true, "correct_option": "CH₃COCH₃ (acetone)", "choice_question": "An organic compound has the composition w_C=62.1%, w_H=10.3%, w_O=27.6%. What is the possible name of the compound?", "conversion_reason": "The answer is a standard chemical term (acetone), which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "CH₃COCH₃ (acetone)", "B": "C₂H₅OH (ethanol)", "C": "CH₃COOH (acetic acid)", "D": "C₃H₈O (propanol)" }, "correct_answer": "A", "explanation": "The correct answer is A (acetone) because its elemental composition (C₃H₆O) matches the given percentages exactly. Option B (ethanol) is a cognitive bias trap - its composition is close but doesn't match the oxygen percentage. Option C (acetic acid) is a professional intuition trap - it has the right elements but incorrect ratios. Option D (propanol) is a multi-level verification trap - it matches the molecular formula but has different structural isomers with varying properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4705, "question": "Suppose that CaO is added as an impurity to CaCl2. If the O2- substitutes for Cl-, what kind of vacancies would you expect to form? How many of these vacancies are created for every O2- added?", "answer": "For O2- substituting for Cl- in CaCl2, chlorine vacancies would be created. For each O2- substituting for a Cl-, one negative charge is added; negative charges are eliminated by creating chlorine vacancies. In order to maintain charge neutrality, one O2- ion will lead to the formation of one chlorine vacancy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述O2-替代Cl-时形成的空位类型及其数量，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目需要理解杂质替代的电荷平衡原理，并分析由此产生的空位类型和数量。虽然涉及基础概念，但需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及杂质掺杂和电荷平衡的概念，要求考生能够分析O2-取代Cl-对晶体缺陷的影响，并计算相应的空位数量。虽然不需要复杂的计算，但需要综合理解电荷补偿机制和缺陷化学的基本原理。", "convertible": true, "correct_option": "Chlorine vacancies would be created, with one chlorine vacancy formed for every O2- added.", "choice_question": "Suppose that CaO is added as an impurity to CaCl2. If the O2- substitutes for Cl-, what kind of vacancies would you expect to form and how many of these vacancies are created for every O2- added?", "conversion_reason": "The answer is a standard explanation involving specific terms (chlorine vacancies) and a quantifiable relationship (one vacancy per O2-), making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chlorine vacancies, 1 per O2-", "B": "Calcium vacancies, 2 per O2-", "C": "Chlorine interstitials, 1 per O2-", "D": "Oxygen vacancies, 0.5 per O2-" }, "correct_answer": "A", "explanation": "The correct answer is A because when O2- substitutes for Cl-, it creates a charge imbalance that must be compensated by chlorine vacancies (1 vacancy per O2- to maintain charge neutrality). Option B exploits the common mistake of focusing on the cation rather than anion substitution. Option C reverses the vacancy concept by suggesting interstitials. Option D creates confusion by suggesting vacancies of the wrong species and incorrect stoichiometry.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 16, "question": "How are unequal-sized spheres packed?", "answer": "In the close packing of unequal-sized spheres, it can be considered that the larger spheres are first closely packed as equal-sized spheres, and then the smaller spheres are filled into the gaps according to their sizes. Slightly larger small spheres fill the octahedral voids, while slightly smaller small spheres fill the tetrahedral voids, forming the close packing of unequal-sized spheres.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对不等径球体的紧密堆积方式进行文字解释和论述，答案提供了详细的描述和解释，符合简答题的特征。 | 知识层次: 题目考查的是对不等径球体紧密堆积的基本概念和原理的理解，属于基础概念的记忆和解释，不需要复杂的计算或综合分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要理解并描述不等径球体的紧密堆积方式，包括大球体的紧密堆积和小球体填充空隙的具体情况（八面体空隙和四面体空隙）。这比单纯记忆定义或分类（等级1）要求更高的概念解释能力，但尚未达到复杂概念体系阐述（等级3）的深度。", "convertible": true, "correct_option": "In the close packing of unequal-sized spheres, it can be considered that the larger spheres are first closely packed as equal-sized spheres, and then the smaller spheres are filled into the gaps according to their sizes. Slightly larger small spheres fill the octahedral voids, while slightly smaller small spheres fill the tetrahedral voids, forming the close packing of unequal-sized spheres.", "choice_question": "How are unequal-sized spheres packed?", "conversion_reason": "The answer is a standard explanation of a concept, which can be used as the correct option in a multiple-choice question. The question can be kept as is or slightly rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Larger spheres form FCC packing while smaller spheres occupy all tetrahedral and octahedral voids", "B": "Smaller spheres form BCC packing while larger spheres occupy the body-centered positions", "C": "Both sphere sizes independently achieve HCP packing in separate domains", "D": "Larger spheres form simple cubic packing with smaller spheres filling all cubic voids" }, "correct_answer": "A", "explanation": "The correct answer is A because in unequal sphere packing, larger spheres typically adopt close-packed structures (FCC or HCP) while smaller spheres fill the interstitial sites. Option B is incorrect as BCC is not a stable packing for unequal spheres. Option C is wrong because the spheres must interact to form a single coherent structure. Option D is misleading as simple cubic is not the most efficient packing for larger spheres. Advanced AI might choose B due to its apparent symmetry or D due to the simplicity of cubic packing.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 741, "question": "In the closest packing of equal-sized spheres, what is the packing arrangement of cubic close packing?", "answer": "(4) ABCABC……", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案，答案以选项编号和内容的形式给出 | 知识层次: 题目考查的是立方密堆积（cubic close packing）的基本排列方式，即ABCABC……的堆叠顺序。这属于材料科学中晶体结构的基础概念记忆，不需要复杂的分析或应用，只需对基本概念的记忆和理解即可回答。 | 难度: 在选择题型中，此题属于基础概念记忆类型，仅需直接回忆立方密堆积的排列方式（ABCABC……），无需理解或辨析其他概念。题目要求的知识掌握深度和解题步骤都非常简单，属于最基础的记忆性题目。", "convertible": true, "correct_option": "ABCABC……", "choice_question": "In the closest packing of equal-sized spheres, what is the packing arrangement of cubic close packing?", "conversion_reason": "原题目已经是选择题格式，且答案明确对应一个选项，可以直接转换为单选题。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ABCABC...", "B": "ABABAB...", "C": "AABBCC...", "D": "ABACAD..." }, "correct_answer": "A", "explanation": "The correct answer is A (ABCABC...) because cubic close packing (CCP) follows this repeating layer sequence. Option B (ABABAB...) is the hexagonal close packing (HCP) arrangement, which is a common confusion. Option C (AABBCC...) mimics FCC unit cell labeling but doesn't represent layer stacking. Option D (ABACAD...) is a mathematically possible but physically unrealistic sequence designed to exploit pattern recognition biases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4662, "question": "Indium (In) has a tetragonal unit cell for which the a and c lattice parameters are 0.459 and 0.495 nm, respectively. The atomic weight of indium is 114.82 g/mol; compute its theoretical density.", "answer": "7.31 g/cm3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（如晶格参数、原子质量和密度公式）来求解理论密度，答案是一个具体的数值结果（7.31 g/cm3），符合计算题的特征。 | 知识层次: 题目要求计算材料的理论密度，涉及基本的晶格参数和原子量的应用，属于直接套用公式进行简单计算的范畴。虽然需要理解晶格参数和密度的关系，但不需要多步计算或综合分析，思维过程较为直接。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用密度计算公式（ρ = n*A / V*N_A），但解题步骤较为直接，仅需代入给定的晶格参数和原子量进行计算，无需复杂的推导或多步骤组合。题目考察的是对基本公式的掌握和简单计算能力，符合等级2的标准。", "convertible": true, "correct_option": "7.31 g/cm3", "choice_question": "Indium (In) has a tetragonal unit cell for which the a and c lattice parameters are 0.459 and 0.495 nm, respectively. The atomic weight of indium is 114.82 g/mol; what is its theoretical density?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.31 g/cm³", "B": "6.89 g/cm³", "C": "7.52 g/cm³", "D": "6.47 g/cm³" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算得到的理论密度值。干扰项B利用了常见错误——忽略tetragonal晶系中c轴与a轴的不同，错误地使用了立方晶系的简化公式。干扰项C是故意在计算中混淆了原子位置因子(APF)的典型错误。干扰项D则是基于错误假设——认为In具有体心立方结构而非实际的面心四方结构。这些干扰项都利用了材料科学计算中常见的直觉陷阱和简化假设错误。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4936, "question": "The index of refraction of quartz is anisotropic. Suppose that visible light is passing from one grain to another of different crystallographic orientation and at normal incidence to the grain boundary. Calculate the reflectivity at the boundary if the indices of refraction for the two grains are 1.544 and 1.553 in the direction of light propagation.", "answer": "the reflectivity at the boundary is 8.45 × 10^{-6}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解反射率，答案是一个具体的数值结果（8.45 × 10^{-6}），这符合计算题的特征。 | 知识层次: 题目要求使用反射率的基本公式进行计算，涉及简单的数值代入和直接套用公式，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目要求计算反射率，直接给出了两个晶粒的折射率，只需套用菲涅尔反射公式（R = ((n1 - n2)/(n1 + n2))^2）进行计算即可。虽然涉及各向异性折射率的概念，但在选择题中只需进行简单数值代入和平方运算，无需复杂推导或多步骤分析。", "convertible": true, "correct_option": "8.45 × 10^{-6}", "choice_question": "The index of refraction of quartz is anisotropic. Suppose that visible light is passing from one grain to another of different crystallographic orientation and at normal incidence to the grain boundary. If the indices of refraction for the two grains are 1.544 and 1.553 in the direction of light propagation, what is the reflectivity at the boundary?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct option can be presented among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.45 × 10^{-6}", "B": "2.89 × 10^{-4}", "C": "1.23 × 10^{-3}", "D": "3.67 × 10^{-5}" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the Fresnel equations for normal incidence reflectivity: R = ((n2-n1)/(n2+n1))^2, where n1=1.544 and n2=1.553. Option B is a common error from incorrectly using the difference in refractive indices without squaring. Option C results from confusing this with birefringence magnitude. Option D is a plausible but incorrect intermediate value that might arise from calculation errors in the denominator term.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 61, "question": "What type of silicate structure does Ca2Al[AlSiO7] belong to?", "answer": "Group (double tetrahedron)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求识别并描述硅酸盐结构类型，需要文字解释和论述，答案形式为特定结构类型的名称而非选择或计算 | 知识层次: 题目考查对硅酸盐结构分类的基础概念记忆，只需识别Ca2Al[AlSiO7]属于双四面体结构类型，无需复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（硅酸盐结构分类），但需要考生准确识别特定化学式对应的硅酸盐结构类型（双四面体结构）。这比单纯记忆定义（等级1）要求更高，需要将化学式与结构分类对应起来，属于概念解释和描述的层次。但不需要进行复杂的概念体系分析或推导（等级3），因此评为等级2。", "convertible": true, "correct_option": "Group (double tetrahedron)", "choice_question": "What type of silicate structure does Ca2Al[AlSiO7] belong to?", "conversion_reason": "The answer is a standard terminology in geology, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Group (double tetrahedron)", "B": "Chain (pyroxene)", "C": "Sheet (phyllosilicate)", "D": "Framework (tectosilicate)" }, "correct_answer": "A", "explanation": "The correct answer is A because Ca2Al[AlSiO7] has a structure with isolated double tetrahedra (Si2O7 groups), characteristic of sorosilicates. Option B is a cognitive bias trap - the formula might superficially resemble chain silicates due to the presence of Al. Option C exploits professional intuition - the layered structure seems plausible given Al substitution. Option D is a multi-level trap - the high Al content could mislead into thinking it's a framework silicate like feldspar.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1902, "question": "What are the main mass transfer mechanisms in liquid phase sintering?", "answer": "(30) Flow mass transfer; (31) Dissolution-precipitation mass transfer", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释液相烧结中的主要传质机制，答案提供了两种机制的简要描述，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查液相烧结中主要传质机制的基本概念记忆和理解，属于定义和分类等记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生准确区分和识别液相烧结中的两种主要传质机制（流动传质和溶解-沉淀传质）。这比单纯记忆单一概念的定义（等级1）要求更高，但不需要进行复杂的概念体系阐述或比较分析（等级3）。", "convertible": true, "correct_option": "Flow mass transfer; Dissolution-precipitation mass transfer", "choice_question": "What are the main mass transfer mechanisms in liquid phase sintering?", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by listing possible mechanisms as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Flow mass transfer and dissolution-precipitation mass transfer", "B": "Diffusion-controlled mass transfer and viscous flow", "C": "Capillary action and grain boundary diffusion", "D": "Surface diffusion and evaporation-condensation" }, "correct_answer": "A", "explanation": "The correct answer is A because liquid phase sintering primarily involves flow mass transfer (due to capillary forces) and dissolution-precipitation mass transfer (material dissolves in liquid and reprecipitates). Option B is incorrect because viscous flow is not a mass transfer mechanism, though it may occur. Option C is incorrect because while capillary action drives flow, grain boundary diffusion is more relevant to solid-state sintering. Option D is incorrect as these are mechanisms for solid-state sintering, not liquid phase processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 472, "question": "4. According to the different atomic arrangement structures at the interface, what three types of interfaces can phase interfaces in solids be divided into?", "answer": "Coherent, semi-coherent, incoherent", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据不同的原子排列结构将固体中的相界面分为三种类型，并需要文字解释和论述，答案形式为列举三种类型，符合简答题的特征。 | 知识层次: 题目考查对固体中相界面分类的基本概念记忆，属于基础概念记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆和识别固体相界面的三种基本分类（共格、半共格、非共格），属于基础概念的直接回忆，无需解释或复杂分析。题目仅测试对定义性知识的掌握，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "Coherent, semi-coherent, incoherent", "choice_question": "According to the different atomic arrangement structures at the interface, which of the following are the three types of interfaces that phase interfaces in solids can be divided into?", "conversion_reason": "The answer is a standard set of terms, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Coherent, semi-coherent, incoherent", "B": "Elastic, plastic, viscoelastic", "C": "Grain boundary, twin boundary, phase boundary", "D": "Perfect, partial, mixed" }, "correct_answer": "A", "explanation": "The correct answer is A because these are the three fundamental types of interfaces based on atomic arrangement mismatch. Option B exploits cognitive bias by using mechanical property terms that sound plausible for interfaces. Option C uses real boundary types but at the wrong classification level (these are boundary types, not atomic arrangement classifications). Option D creates confusion by borrowing terminology from dislocation theory, which is related but not applicable to interface classification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1395, "question": "Calculate the coordination number of the cation in the compound K2O, given r(K+)=0.132nm, r(O2-)=0.132nm", "answer": "12", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的离子半径数据进行数值计算，应用相关公式来确定配位数，最终答案为具体的数值结果。 | 知识层次: 题目涉及基本的离子半径比计算和配位数的确定，属于直接套用公式和简单计算的应用层次，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用半径比公式计算配位数，属于单一公式直接计算的简单题目。题目中已经给出了离子半径，只需套用半径比规则即可得出答案，无需复杂分析或组合多个公式。", "convertible": true, "correct_option": "12", "choice_question": "What is the coordination number of the cation in the compound K2O, given r(K+)=0.132nm, r(O2-)=0.132nm?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "12", "C": "选项D", "D": "选项B" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1046, "question": "Analyze the equilibrium crystallization process of the Fe-0.4%C alloy and indicate the phase composition at room temperature", "answer": "When C%=0.4%, the Fe-C alloy cools to room temperature, and the phase constituents are α+Fe3C", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求分析Fe-0.4%C合金的平衡结晶过程并指出室温下的相组成，需要文字解释和论述，答案也是以文字形式给出相组成的具体结果 | 知识层次: 题目要求分析Fe-0.4%C合金的平衡结晶过程并指出室温下的相组成，这需要理解相图的基本原理，并能将相图知识应用于具体合金成分的分析。虽然不涉及复杂计算，但需要将多个概念（如相图、相组成）关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解铁碳相图的基本概念，掌握不同碳含量下的相变过程，并能正确识别室温下的相组成。虽然题目涉及多步计算和概念关联，但在选择题型中通过选项提示可以降低部分分析难度。", "convertible": true, "correct_option": "α+Fe3C", "choice_question": "Analyze the equilibrium crystallization process of the Fe-0.4%C alloy and indicate the phase composition at room temperature. Which of the following is the correct phase composition?", "conversion_reason": "The answer is a standard term (α+Fe3C) that can be presented as a choice in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct phase composition from given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "α+Fe3C", "B": "γ+Fe3C", "C": "α+γ", "D": "α+γ+Fe3C" }, "correct_answer": "A", "explanation": "The correct phase composition for Fe-0.4%C alloy at room temperature is α (ferrite) + Fe3C (cementite). This is a hypoeutectoid steel where the final microstructure consists of proeutectoid ferrite and pearlite (α+Fe3C). Option B incorrectly suggests austenite (γ) is present at room temperature, exploiting the common misconception that high-temperature phases may persist. Option C omits cementite, targeting the oversight of the eutectoid reaction. Option D adds γ phase which cannot exist at room temperature in equilibrium conditions, creating a multi-layer verification trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4050, "question": "In order for a semiconductor to exhibit extrinsic electrical characteristics, relatively high impurity concentrations are required.(a) True(b) False", "answer": "False. Even when minute impurity concentrations (e.g., 1 atom in 10^{12} ) are present in a semiconductor, its electrical characteristics will be extrinsic.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错，答案直接给出了True或False的判断，并附带简要解释 | 知识层次: 题目考查对半导体本征和外征特性的基本概念的理解，属于基础概念记忆范畴，不需要复杂的应用或分析。 | 难度: 该题目属于基础概念正误判断，仅需记忆半导体掺杂的基本原理即可作答，无需复杂分析或概念比较。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "False. Even when minute impurity concentrations (e.g., 1 atom in 10^{12} ) are present in a semiconductor, its electrical characteristics will be extrinsic.", "choice_question": "In order for a semiconductor to exhibit extrinsic electrical characteristics, relatively high impurity concentrations are required.(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials will eventually crystallize when heated above their glass transition temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many amorphous materials can crystallize above their glass transition temperature, some systems (like certain polymer blends or inorganic glasses) are designed to have extremely high crystallization resistance. The statement's use of 'all' creates an absolute claim that doesn't account for these exceptions. Additionally, crystallization kinetics depend on factors like cooling rate and material composition, not just temperature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2985, "question": "Polymer materials are", "answer": "Materials with polymer compounds as the main component", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述聚合物材料的定义，答案是一个简短的文字描述而非选择、判断或计算 | 知识层次: 题目考查对聚合物材料基本定义的记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目仅要求识别聚合物材料的基本定义，属于最基础的概念记忆层次。正确选项直接对应题干中的核心概念，无需复杂推理或比较分析，解题步骤极为简单。", "convertible": true, "correct_option": "Materials with polymer compounds as the main component", "choice_question": "Which of the following best describes polymer materials?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice format by providing the correct option among plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Materials with polymer compounds as the main component", "B": "Materials exhibiting viscoelastic behavior at all temperatures", "C": "Materials composed of long-chain molecules with covalent crosslinks", "D": "Materials that always demonstrate thermoplastic characteristics" }, "correct_answer": "A", "explanation": "The correct answer is A because polymer materials are fundamentally defined by having polymer compounds as their primary constituent. Option B exploits the cognitive bias that all polymers are viscoelastic, ignoring that this behavior is temperature-dependent. Option C uses a professional intuition trap by implying crosslinks are essential, while many polymers are linear. Option D creates a multi-level verification trap by suggesting all polymers are thermoplastic, disregarding thermosetting polymers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3489, "question": "Why does W18Cr4V steel need to undergo three tempering cycles at 560°C after quenching?", "answer": "Because W18Cr4V steel contains about 20%~25% retained austenite in the quenched state, which is difficult to fully eliminate with a single tempering. Three tempering cycles can reduce the retained austenite to a minimum (about 15% remains after the first tempering, 3%~5% after the second, and 1%~2% after the third). Each subsequent tempering also relieves the internal stress generated by the transformation of austenite into martensite during the previous tempering. The tempered microstructure consists of tempered martensite + a small amount of retained austenite + carbides.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么W18Cr4V钢需要在淬火后进行三次560°C的回火处理，答案提供了详细的文字解释和论述，说明每次回火的作用和效果，符合简答题的特征。 | 知识层次: 题目需要解释W18Cr4V钢在淬火后需要进行三次回火的原因，涉及残余奥氏体的转变、回火过程中内应力的消除以及显微组织的演变。这需要综合运用材料科学中的相变理论、热处理原理和组织分析知识，进行多步骤的推理和机理解释。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Because W18Cr4V steel contains about 20%~25% retained austenite in the quenched state, which is difficult to fully eliminate with a single tempering. Three tempering cycles can reduce the retained austenite to a minimum (about 15% remains after the first tempering, 3%~5% after the second, and 1%~2% after the third). Each subsequent tempering also relieves the internal stress generated by the transformation of austenite into martensite during the previous tempering. The tempered microstructure consists of tempered martensite + a small amount of retained austenite + carbides.", "choice_question": "Why does W18Cr4V steel need to undergo three tempering cycles at 560°C after quenching?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be kept as is for the multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To fully eliminate retained austenite through multiple phase transformations", "B": "To achieve a balance between hardness and toughness by controlling carbide precipitation", "C": "To prevent temper brittleness by maintaining the temperature below 400°C", "D": "To reduce the martensite content and increase ductility through recrystallization" }, "correct_answer": "A", "explanation": "The correct answer is A because W18Cr4V steel requires three tempering cycles primarily to transform retained austenite into martensite and then temper it, which cannot be achieved in a single cycle. Option B is a cognitive bias trap, as it describes a general purpose of tempering but not the specific reason for three cycles. Option C exploits confusion with temper brittleness ranges in other steels. Option D is a professional intuition trap, as it incorrectly suggests the primary goal is ductility improvement rather than austenite transformation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 95, "question": "The Schottky defect formation energy of Mg0 crystal is 84 kJ/mol. Calculate the defect concentration of this crystal at 1000K and 1500K.", "answer": "$\\\\mathrm{n}/\\\\mathrm{N}{=}\\\\mathrm{exp}$ (-E/2RT), $\\\\mathrm{R}{=}8.314$, $\\\\mathrm{T}{=}1000\\\\mathrm{k}$ :n/N=6. $4\\\\times{10}^{-3}$ $\\\\mathrm{T}=1500\\\\mathrm{k}$ $\\\\mathrm{n}/\\\\mathrm{N}{=}3.5\\\\times{10}^{-2}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案给出了具体的计算过程和结果 | 知识层次: 题目主要考查基本公式的应用和简单计算，涉及Schottky缺陷形成能和浓度的直接计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用Schottky缺陷浓度公式，但题目已经提供了所有必要的参数和公式，仅需进行简单的代入和计算。解题步骤较为直接，无需复杂的推导或组合多个公式。因此，在选择题型内属于中等偏下的难度等级。", "convertible": true, "correct_option": "T=1000K: n/N=6.4×10⁻³; T=1500K: n/N=3.5×10⁻²", "choice_question": "The Schottky defect formation energy of Mg0 crystal is 84 kJ/mol. What is the defect concentration of this crystal at 1000K and 1500K?", "conversion_reason": "The answer is a specific numerical result derived from a calculation, which can be presented as a choice among plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "T=1000K: n/N=6.4×10⁻³; T=1500K: n/N=3.5×10⁻²", "B": "T=1000K: n/N=1.2×10⁻²; T=1500K: n/N=6.8×10⁻²", "C": "T=1000K: n/N=8.4×10⁻⁵; T=1500K: n/N=4.7×10⁻⁴", "D": "T=1000K: n/N=3.2×10⁻³; T=1500K: n/N=1.75×10⁻²" }, "correct_answer": "A", "explanation": "正确答案A使用正确的Schottky缺陷浓度公式n/N=exp(-Ef/2kT)计算得出。干扰项B通过错误地忽略1/2系数导致浓度高估；干扰项C错误地将kJ单位直接用于指数计算而未转换为J/mol；干扰项D看似是A的一半，利用了AI可能对系数1/2位置记忆模糊的弱点。所有干扰项都利用了材料科学中能量单位转换和指数计算容易出错的特性。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2228, "question": "Determine whether the following statement is correct. (3) Polygonization causes the scattered dislocations to gather together to form dislocation walls, and the superposition of dislocation stress fields increases the lattice distortion.", "answer": "Incorrect. During the polygonization process, the vacancy concentration decreases and dislocations recombine, causing dislocations of opposite signs to cancel each other out, reducing dislocation density and thereby alleviating lattice distortion.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断陈述的正确性，答案明确指出了陈述的错误并解释了原因，符合判断题的特征。 | 知识层次: 题目涉及对多边形化过程中位错行为的理解，需要将位错重组、应力场叠加和晶格畸变等概念进行关联分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合分析多边形化过程中位错重组和应力场变化的复杂关系。题目不仅要求理解位错运动的基本概念，还需要掌握位错相互作用对晶格畸变的影响机制。正确选项涉及多步推理过程（位错重组→符号相反位错抵消→位错密度降低→晶格畸变减轻），且需要将多个材料科学概念（多边形化、位错应力场、晶格畸变）关联起来进行判断。这超出了简单记忆或单一概念应用的层次，属于需要综合分析能力的中等应用题型。", "convertible": true, "correct_option": "Incorrect. During the polygonization process, the vacancy concentration decreases and dislocations recombine, causing dislocations of opposite signs to cancel each other out, reducing dislocation density and thereby alleviating lattice distortion.", "choice_question": "Determine whether the following statement is correct. (3) Polygonization causes the scattered dislocations to gather together to form dislocation walls, and the superposition of dislocation stress fields increases the lattice distortion.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all metallic materials, polygonization always leads to the formation of dislocation walls that increase the overall lattice distortion energy.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While polygonization can lead to dislocation wall formation in some cases, this is not universally true for all metallic materials. The process depends on factors like crystal structure, temperature, and initial dislocation arrangement. Additionally, the recombination of dislocations during polygonization typically reduces rather than increases lattice distortion energy. The absolute terms 'all' and 'always' make this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4536, "question": "For a polymer-matrix fiber-reinforced composite, list three functions of the matrix phase.", "answer": "For polymer-matrix fiber-reinforced composites, three functions of the polymer-matrix phase are: (1) to bind the fibers together so that the applied stress is distributed among the fibers; (2) to protect the surface of the fibers from being damaged; and (3) to separate the fibers and inhibit crack propagation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列出聚合物基纤维增强复合材料中基体相的三个功能，答案以文字解释和论述的形式给出，没有选项或计算要求。 | 知识层次: 题目考查对聚合物基纤维增强复合材料中基体相功能的基本概念记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列出三个功能，但这些都是基础概念记忆层面的知识点，不需要复杂的分析或推理。学生只需回忆并准确描述聚合物基体相在纤维增强复合材料中的三个基本功能即可。相较于等级1的简单定义，该题目需要更多的概念解释和描述，但尚未达到等级3的复杂概念体系阐述水平。", "convertible": true, "correct_option": "to bind the fibers together so that the applied stress is distributed among the fibers; to protect the surface of the fibers from being damaged; to separate the fibers and inhibit crack propagation", "choice_question": "Which of the following are functions of the matrix phase in a polymer-matrix fiber-reinforced composite?", "conversion_reason": "The original short answer question asks for a list of functions, which can be converted into a multiple-choice format by providing the correct functions as one of the options. The answer is a standard set of functions that can be clearly identified as the correct choice among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To provide the primary load-bearing capability through its high elastic modulus", "B": "To chemically bond with fiber surfaces creating covalent crosslinks", "C": "To prevent fiber-fiber contact by maintaining precise inter-fiber spacing", "D": "To absorb impact energy through plastic deformation of the matrix" }, "correct_answer": "C", "explanation": "The correct answer is C because the matrix phase's key functions include separating fibers to inhibit crack propagation. Option A is incorrect as fibers provide primary load-bearing, not the matrix. Option B is a cognitive bias trap - while interfacial bonding occurs, covalent crosslinks are not a standard matrix function. Option D is an intuition trap - while some energy absorption occurs, plastic deformation is not a primary design intent for polymer matrices in structural composites.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4513, "question": "List the two molecular characteristics that are essential for elastomers.", "answer": "Two molecular characteristics essential for elastomers are: (1) they must be amorphous, having chains that are extensively coiled and kinked in the unstressed state; and (2) there must be some crosslinking.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列出两个分子特性，答案以文字解释的形式给出，没有选项或计算要求，符合简答题的特征。 | 知识层次: 题目考查对弹性体基本分子特性的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目要求考生回忆并识别出弹性体的两个基本分子特性。虽然需要记忆两个关键点（非晶态结构和交联），但这些都是基础概念记忆层面的内容，不需要复杂的推理或分析。相较于只需回忆单一基本定义的等级1题目，此题稍微复杂一些，但仍属于概念解释和描述的范畴。", "convertible": true, "correct_option": "They must be amorphous, having chains that are extensively coiled and kinked in the unstressed state; and there must be some crosslinking.", "choice_question": "Which of the following are the two molecular characteristics essential for elastomers?", "conversion_reason": "The answer is a standard description of molecular characteristics, which can be converted into a multiple-choice format by presenting the correct option among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High degree of crystallinity with oriented molecular chains", "B": "Amorphous structure with crosslinked polymer chains", "C": "Semi-crystalline morphology with spherulitic domains", "D": "Linear polymer chains with high molecular weight" }, "correct_answer": "B", "explanation": "The correct answer is B because elastomers require an amorphous structure to allow large reversible deformations, and crosslinking is essential to prevent permanent chain slippage. Option A is incorrect because crystallinity restricts chain mobility needed for elasticity. Option C is a trap for those confusing elastomers with tough plastics. Option D exploits the common misconception that high MW alone ensures elasticity, ignoring the need for crosslinks.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3047, "question": "Ceramic materials can be used as cutting tool materials, and can also be used as thermal insulation materials.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（Ceramic materials can be used as cutting tool materials, and can also be used as thermal insulation materials），并要求判断其正确性（答案：√），这符合判断题的特征。 | 知识层次: 题目考查对陶瓷材料基本用途的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆陶瓷材料的常见用途即可作答，无需深入理解或分析多个概念。题目直接陈述了陶瓷材料的两种应用，正确选项明确，属于最基础难度的记忆性知识题目。", "convertible": true, "correct_option": "√", "choice_question": "Ceramic materials can be used as cutting tool materials, and can also be used as thermal insulation materials.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit both high hardness for cutting applications and low thermal conductivity for insulation purposes.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics can serve both purposes, this is not universally true. Some ceramics like alumina are hard but have moderate thermal conductivity, while others like porous ceramics are excellent insulators but lack cutting hardness. The statement falsely generalizes that all ceramics possess both properties simultaneously.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2400, "question": "In a Ni single crystal, there is a dislocation with Burgers vector b=a[0]12 on the (11T) plane. The lattice constant a=0.35 nm. What is the length of the dislocation's Burgers vector?", "answer": "Solution: The Ni crystal has an fcc structure, and the Burgers vector b is of the [110]/2 type. Therefore, the length of the Burgers vector is b=a√2/2=0.35√2/2=0.254 nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求计算位错的Burgers矢量的长度，需要通过给定的晶格常数和Burgers矢量的类型进行数值计算，最终得出具体的数值结果。答案中展示了具体的计算过程和公式应用，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式应用和简单计算，即通过已知的晶格常数和Burgers向量的类型直接套用公式计算其长度。虽然需要理解Burgers向量的类型和fcc结构的基本知识，但整体思维过程较为直接，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要知道fcc结构中Burgers vector的类型和计算公式，但解题步骤相对直接，仅需套用公式b=a√2/2并进行简单计算即可得出答案。不需要多个公式组合或复杂的概念分析，因此在选择题型内属于等级2难度。", "convertible": true, "correct_option": "0.254 nm", "choice_question": "In a Ni single crystal, there is a dislocation with Burgers vector b=a[0]12 on the (11T) plane. The lattice constant a=0.35 nm. What is the length of the dislocation's Burgers vector?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.254 nm", "B": "0.35 nm", "C": "0.495 nm", "D": "0.175 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.254 nm) because the magnitude of the Burgers vector is calculated as a√(0² + 1² + 2²)/2 = 0.35×√5/2 ≈ 0.254 nm. Option B (0.35 nm) exploits the cognitive bias of directly using the lattice constant without proper vector calculation. Option C (0.495 nm) is designed as a professional intuition trap by incorrectly using a√(1² + 1² + 1²) which would apply to [111] direction. Option D (0.175 nm) is a unit confusion trap using a/2 without vector considerations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1382, "question": "What is the phenomenon of work hardening in metals?", "answer": "The phenomenon where the applied flow stress continuously increases with the increase of strain during the plastic deformation of metallic materials is called work hardening. Alternatively, the phenomenon where the strength and hardness of metallic materials increase, while the plasticity and toughness decrease after cold plastic deformation, is called work hardening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"work hardening\"现象进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即工作硬化现象的定义和基本特征，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆\"work hardening\"的基本定义和现象描述，但不需要进行复杂的比较分析或推导。正确选项提供了清晰的概念解释，属于基础概念记忆层次，符合选择题型中等级2的难度标准。", "convertible": true, "correct_option": "The phenomenon where the applied flow stress continuously increases with the increase of strain during the plastic deformation of metallic materials is called work hardening. Alternatively, the phenomenon where the strength and hardness of metallic materials increase, while the plasticity and toughness decrease after cold plastic deformation, is called work hardening.", "choice_question": "Which of the following best describes the phenomenon of work hardening in metals?", "conversion_reason": "The answer is a standard definition of a scientific concept, which can be presented as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The increase in dislocation density during plastic deformation creates barriers to further dislocation motion, leading to increased strength", "B": "The alignment of crystal lattices along the deformation direction reduces atomic spacing and increases bonding strength", "C": "The formation of metastable phases during deformation provides additional strengthening through precipitation effects", "D": "The reduction in grain boundary area due to deformation-induced grain elongation decreases diffusion pathways" }, "correct_answer": "A", "explanation": "Option A correctly describes the fundamental dislocation-based mechanism of work hardening. Option B exploits the common misconception about lattice alignment being the primary cause. Option C introduces a precipitation hardening concept that doesn't apply to pure work hardening. Option D uses a grain boundary diffusion mechanism that's irrelevant to the immediate strengthening effect of cold working.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1368, "question": "What types of cementite may exist in iron-carbon alloys?", "answer": "Primary cementite, eutectic cementite, secondary cementite, eutectoid cementite, tertiary cementite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举铁碳合金中可能存在的渗碳体类型，答案以文字形式给出具体分类，不需要计算或选择，属于需要文字解释的简答题类型。 | 知识层次: 题目考查铁碳合金中不同类型渗碳体的分类记忆，属于基础概念的记忆和理解范畴，不需要复杂的分析或综合应用。 | 难度: 该题目属于选择题型，要求考生识别并记忆铁碳合金中可能存在的不同类型渗碳体（Primary cementite, eutectic cementite, secondary cementite, eutectoid cementite, tertiary cementite）。虽然涉及多个分类，但都属于基础概念记忆范畴，不需要复杂的分析或比较。在选择题型中，这属于中等难度，因为需要考生对材料科学中的基本分类有清晰记忆，但不需要深入理解或应用这些概念。", "convertible": true, "correct_option": "Primary cementite, eutectic cementite, secondary cementite, eutectoid cementite, tertiary cementite", "choice_question": "Which of the following are types of cementite that may exist in iron-carbon alloys?", "conversion_reason": "The answer is a standard list of terms, which can be converted into a multiple-choice question format by presenting these terms as options and asking the student to select the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Primary cementite, eutectic cementite, secondary cementite, eutectoid cementite", "B": "Primary cementite, proeutectoid cementite, secondary cementite, eutectoid cementite", "C": "Eutectic cementite, secondary cementite, eutectoid cementite, tertiary cementite", "D": "Primary cementite, eutectic cementite, secondary cementite, eutectoid cementite, tertiary cementite" }, "correct_answer": "D", "explanation": "The correct answer includes all five types of cementite that can exist in iron-carbon alloys. Option A misses tertiary cementite which forms below 727°C. Option B incorrectly includes proeutectoid cementite which is not a distinct type. Option C misses primary cementite that forms directly from liquid. The difficulty lies in recognizing tertiary cementite's existence and avoiding confusion with proeutectoid cementite which is a morphological description rather than a distinct phase type.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4051, "question": "The following electrical characteristics have been determined for both intrinsic and n-type extrinsic indium phosphide (InP) at room temperature:\n\\[\n\\begin{array}{llll}\n\\sigma(\\Omega·\\mathbf{m})^{-1} & \\boldsymbol{n}\\left(\\mathbf{m}^{-3}\\right) & \\boldsymbol{p}\\left(\\mathbf{m}^{-3}\\right) \\\\\n\\text { Intrinsic } & 2.5 × 10^{-6} & 3.0 × 10^{13} & 3.0 × 10^{13} \\\\\n\\text { Extrinsic } & 3.6 × 10^{-5} & 4.5 × 10^{14} & 2.0 × 10^{12}\n\\end{array}\n\\]\nCalculate electron and hole mobilities.\n\\mu_{\\mathrm{e}}=\n\\mu_{h}=", "answer": "\\mu_{\\mathrm{e}} = 0.50 \\, m^{2} / \\mathrm{v}·s \\mu_{h} = 0.02 \\, m^{2} / \\mathrm{v}·s", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的电导率、电子浓度和空穴浓度数据，应用相关公式计算电子和空穴的迁移率。解答过程涉及数值计算和公式应用，最终需要给出具体的数值结果。 | 知识层次: 题目要求应用基本电导率公式（σ = n·e·μ）进行简单计算，仅需直接套用公式并代入给定数值即可求解电子和空穴迁移率，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，需要考生掌握基本的电导率公式（σ = n·e·μ）并进行简单的代数运算。虽然涉及两个变量（电子和空穴迁移率），但计算过程直接且无需复杂的推导或概念组合，因此属于等级2难度。", "convertible": true, "correct_option": "μₑ = 0.50 m²/V·s, μₕ = 0.02 m²/V·s", "choice_question": "Given the following electrical characteristics for intrinsic and n-type extrinsic indium phosphide (InP) at room temperature, calculate the electron and hole mobilities (μₑ and μₕ).", "conversion_reason": "The question involves a calculation with a specific numerical answer, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "μₑ = 0.50 m²/V·s, μₕ = 0.02 m²/V·s", "B": "μₑ = 0.02 m²/V·s, μₕ = 0.50 m²/V·s", "C": "μₑ = 1.25 m²/V·s, μₕ = 0.05 m²/V·s", "D": "μₑ = 0.05 m²/V·s, μₕ = 1.25 m²/V·s" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately reflects the calculated mobilities using the given intrinsic and extrinsic conductivity data. Option B reverses the mobility values, exploiting the common confusion between electron and hole mobilities in compound semiconductors. Option C presents values that might seem plausible if one incorrectly assumes higher mobilities from the conductivity values alone, without properly accounting for carrier concentrations. Option D combines the reversal error of B with the overestimation error of C, creating a particularly deceptive trap for those who make both mistakes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1397, "question": "What basic conditions must be met for atomic diffusion in solids?", "answer": "Atomic diffusion in solids requires the presence of a chemical potential gradient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释原子扩散在固体中的基本条件，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查原子扩散的基本条件，属于基本原理的记忆和理解范畴，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目仅考察对原子扩散基本条件的记忆，属于基础概念的直接复现。正确选项明确给出了定义性答案，无需复杂推理或概念比较，符合等级1\"基本定义简答\"的特征。选择题型中此类题目只需识别关键词\"chemical potential gradient\"即可作答，属于难度最低的认知层次。", "convertible": true, "correct_option": "Atomic diffusion in solids requires the presence of a chemical potential gradient.", "choice_question": "Which of the following is a basic condition that must be met for atomic diffusion in solids?", "conversion_reason": "The answer is a standard concept that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Presence of a chemical potential gradient", "B": "Existence of a temperature gradient above the Debye temperature", "C": "Availability of sufficient activation energy for vacancy formation", "D": "Presence of a crystallographic orientation mismatch exceeding 15°" }, "correct_answer": "A", "explanation": "The correct answer is A because atomic diffusion fundamentally requires a driving force, which is provided by a chemical potential gradient. Option B exploits the common misconception that temperature alone drives diffusion, while actually needing both thermal activation and a driving force. Option C is a half-truth that traps systems by focusing only on the vacancy mechanism while neglecting the necessity of a driving force. Option D uses a real materials science concept (grain boundary diffusion) but presents an arbitrary numerical threshold that doesn't fundamentally govern diffusion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 330, "question": "Why is the liquid/solid interface front of an alloy more prone to undercooling during solidification compared to that of a pure metal?", "answer": "The interface front of an alloy exhibits constitutional undercooling, where solute enrichment at the front raises the local melting point, making undercooling more likely to occur.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释合金在凝固过程中比纯金属更容易发生过冷的原因，答案需要文字解释和论述，涉及材料科学中的概念和原理，属于简答题类型。 | 知识层次: 题目需要解释合金凝固过程中液/固界面前沿更容易发生过冷的原因，涉及溶质富集和局部熔点升高的机理分析，属于综合运用和推理分析的复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The interface front of an alloy exhibits constitutional undercooling, where solute enrichment at the front raises the local melting point, making undercooling more likely to occur.", "choice_question": "Why is the liquid/solid interface front of an alloy more prone to undercooling during solidification compared to that of a pure metal?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The solute enrichment at the interface creates a local composition gradient that effectively raises the melting point", "B": "Alloys have higher thermal conductivity than pure metals, causing faster heat dissipation at the interface", "C": "The presence of multiple elements increases atomic vibration frequency, lowering the energy barrier for nucleation", "D": "Impurity atoms in alloys disrupt the crystal lattice symmetry, reducing the interfacial energy required for solidification" }, "correct_answer": "A", "explanation": "Correct answer A describes constitutional undercooling where solute buildup changes local equilibrium conditions. B is wrong because alloys typically have lower thermal conductivity. C misapplies vibration theory to nucleation kinetics. D confuses lattice distortion effects with interfacial energy thermodynamics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 852, "question": "What are the dislocation name, Burgers vector, dislocation nature, formation method, and motion state of the Frank partial dislocation in FCC crystals?", "answer": "Frank partial dislocation; 1 <111> 3; edge type; formed by inserting or removing a layer of {111} close-packed plane in a local region of the crystal; can only climb, cannot glide", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求详细解释Frank partial dislocation在FCC晶体中的多个属性（名称、Burgers矢量、位错性质、形成方法和运动状态），答案以文字形式给出详细说明，符合简答题的特征。 | 知识层次: 题目要求回答Frank部分位错的多个属性（名称、Burgers矢量、位错性质、形成方法和运动状态），涉及多个概念的关联和综合分析，需要理解位错的基本性质及其在FCC晶体中的具体表现，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，要求考生掌握Frank部分位错的多个关键属性（名称、Burgers矢量、位错性质、形成方法和运动状态），并能够将这些概念综合关联起来。题目不仅考察单一知识点的记忆，还需要对FCC晶体中位错行为的深入理解，涉及多步分析和概念整合。此外，正确选项中的信息较为复杂，需要考生具备较强的综合分析能力。", "convertible": true, "correct_option": "Frank partial dislocation; 1 <111> 3; edge type; formed by inserting or removing a layer of {111} close-packed plane in a local region of the crystal; can only climb, cannot glide", "choice_question": "Which of the following correctly describes the dislocation name, Burgers vector, dislocation nature, formation method, and motion state of the Frank partial dislocation in FCC crystals?", "conversion_reason": "The answer is a standard set of terms and concepts that can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Frank partial dislocation; 1/3 <111>; edge type; formed by inserting or removing a {111} layer; can only climb", "B": "Shockley partial dislocation; 1/6 <112>; mixed type; formed by shear deformation; can glide on {111} planes", "C": "Frank partial dislocation; 1/2 <110>; screw type; formed by vacancy condensation; can glide and climb", "D": "Perfect dislocation; 1/2 <110>; edge type; formed by plastic deformation; can glide on {111} planes" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes all characteristics of Frank partial dislocations in FCC crystals: Burgers vector magnitude (1/3), direction (<111>), edge nature, formation by layer insertion/removal, and climb-only motion. Option B incorrectly describes Shockley partial dislocations. Option C uses correct dislocation name but wrong Burgers vector and motion capability. Option D describes perfect dislocations, creating confusion through dislocation type mixing. The key traps are: 1) Burgers vector magnitude confusion (1/3 vs 1/6 vs 1/2), 2) mixing partial/perfect dislocation properties, and 3) incorrect motion capabilities (glide vs climb).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3302, "question": "Is the statement that the plasticity and toughness of martensite mainly depend on its substructure correct? Why?", "answer": "Yes. The plasticity and toughness of martensite mainly depend on its substructure.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求判断一个陈述是否正确（\"Is the statement...correct?\"），并且答案直接给出了对陈述的判断（\"Yes\"），这符合判断题的特征。虽然题目还要求解释原因（\"Why?\"），但主要考察的是对陈述真伪的判断能力。 | 知识层次: 题目不仅需要判断陈述的对错，还需要解释为什么，涉及对马氏体亚结构与其塑性和韧性关系的深入理解和分析。这需要综合运用材料科学知识，进行推理和机理解释，属于较高层次的认知能力要求。 | 难度: 在选择题型中，该题目属于高难度等级。题目要求考生不仅理解马氏体的塑性和韧性与亚结构的关系，还需要进行深度分析和机理解释。正确选项涉及复杂的材料科学知识，需要综合运用多个概念并进行推理分析，才能得出正确结论。这种题目在选择题型中属于较高层次的认知要求，因此难度等级为5。", "convertible": true, "correct_option": "Yes. The plasticity and toughness of martensite mainly depend on its substructure.", "choice_question": "Is the statement that the plasticity and toughness of martensite mainly depend on its substructure correct? Why?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The plasticity and toughness of martensite always depend solely on its substructure.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the substructure of martensite (such as lath or plate morphology) significantly influences its plasticity and toughness, other factors like carbon content, prior austenite grain size, and tempering conditions also play crucial roles. The use of 'always' and 'solely' makes this statement incorrect as it oversimplifies the complex relationship between martensite's properties and its microstructure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1398, "question": "According to the concentration distribution of the diffusing component, what are the basic types of diffusion?", "answer": "Self-diffusion and interdiffusion", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释扩散的基本类型，答案需要文字描述（Self-diffusion and interdiffusion），属于简答题的特征 | 知识层次: 题目考查扩散基本类型的记忆和理解，属于基础概念的分类范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求识别扩散的基本类型（自扩散和互扩散），属于基础概念记忆的简单题目。学生只需记住这两个分类即可正确作答，无需进行概念解释或复杂分析。", "convertible": true, "correct_option": "Self-diffusion and interdiffusion", "choice_question": "According to the concentration distribution of the diffusing component, what are the basic types of diffusion?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Self-diffusion and interdiffusion", "B": "Fickian and non-Fickian diffusion", "C": "Vacancy and interstitial diffusion", "D": "Thermal and chemical diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because the question specifically asks about classification based on concentration distribution, where self-diffusion (equal concentration) and interdiffusion (concentration gradient) are the fundamental types. Option B is incorrect as it describes diffusion mechanisms by kinetics rather than concentration. Option C is a trap as it describes atomic-scale mechanisms that are independent of concentration distribution. Option D exploits the common confusion between driving forces (thermal/chemical) and the resulting concentration profiles.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2524, "question": "Explain the term: phase", "answer": "A portion or region within an alloy that has the same (or continuously varying) composition, structure, and properties.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释术语\"phase\"，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对\"phase\"这一基本概念的定义记忆和理解，属于材料科学中最基础的概念性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"phase\"的基本定义，属于最基础的概念记忆层次。题目正确选项直接给出了术语的标准定义，不需要任何解释、分析或比较过程，完全符合等级1\"基本定义简答\"的难度标准。", "convertible": true, "correct_option": "A portion or region within an alloy that has the same (or continuously varying) composition, structure, and properties.", "choice_question": "Which of the following best defines the term 'phase'?", "conversion_reason": "The answer is a standard definition of a term, which can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A portion or region within an alloy that has the same (or continuously varying) composition, structure, and properties", "B": "A distinct state of matter (solid, liquid, gas) with uniform physical properties throughout", "C": "The angular relationship between crystallographic planes in a polycrystalline material", "D": "A thermodynamic state characterized by a specific free energy minimum under given conditions" }, "correct_answer": "A", "explanation": "Option A is the correct definition of 'phase' in materials science, encompassing composition, structure and property uniformity. Option B is a common misconception - while phases can correspond to states of matter, the definition is broader. Option C describes crystallographic orientation, not phase. Option D is a thermodynamic prerequisite but doesn't fully capture the materials science definition. The difficulty lies in distinguishing the materials-specific definition (A) from more general thermodynamic (D) or physical (B) interpretations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4877, "question": "What is the distinction between dye and pigment colorants?", "answer": "The distinction between dye and pigment colorants is that a dye dissolves within and becomes a part of the polymer structure, whereas a pigment does not dissolve, but remains as a separate phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释染料和颜料着色剂之间的区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查染料和颜料的基本定义和区别，属于基础概念的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生区分染料和颜料两种着色剂的关键差异（溶解性与聚合物结构的关系）。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。正确选项明确指出了两者的核心区别，考生只需理解并选择这一关键差异点即可。", "convertible": true, "correct_option": "a dye dissolves within and becomes a part of the polymer structure, whereas a pigment does not dissolve, but remains as a separate phase", "choice_question": "What is the distinction between dye and pigment colorants?", "conversion_reason": "The answer is a standard explanation of the distinction between dye and pigment colorants, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dyes chemically bond to the substrate while pigments physically adhere to the surface", "B": "Dyes are organic compounds whereas pigments are always inorganic materials", "C": "Dyes dissolve within and become part of the polymer structure, while pigments remain as a separate phase", "D": "Pigments provide better color fastness than dyes in all application scenarios" }, "correct_answer": "C", "explanation": "The correct answer is C because it accurately describes the fundamental distinction: dyes dissolve and integrate into the material's structure, while pigments remain as discrete particles. Option A is incorrect because both dyes and pigments can form various types of interactions with substrates. Option B is wrong as pigments can be organic (e.g., phthalocyanines) and some dyes contain metal complexes. Option D is a common misconception - while pigments generally have better lightfastness, dyes often outperform pigments in terms of washfastness for textile applications.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 855, "question": "Explain one of the main mechanisms of alloy strengthening from a microstructural perspective: solid solution strengthening, and provide examples", "answer": "Solid solution strengthening occurs when alloying atoms dissolved in the lattice interstices or lattice points, due to their different sizes compared to the matrix atoms, create stress fields that hinder dislocation movement. Examples include Cottrell atmospheres and Suzuki atmospheres. The former refers to interstitial atoms preferentially distributing in the tensile stress region of edge dislocations in BCC metals, pinning the dislocations. The latter involves alloying elements preferentially distributing in the stacking fault regions of extended dislocations in FCC metals, reducing stacking fault energy, expanding the stacking fault region, and making the slip of extended dislocations more difficult.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释合金强化的主要机制之一（固溶强化），并从微观结构角度进行说明，同时提供例子。答案需要详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求从微观结构角度解释固溶强化的主要机制，并提供具体例子（如Cottrell和Suzuki气团）。这需要深入理解位错与溶质原子的相互作用、应力场分布以及不同晶体结构（BCC/FCC）中的强化机理，涉及多概念关联和机理解释，属于综合分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅掌握合金强化的基本概念，还需要深入理解固溶强化的微观机制，包括位错与溶质原子的相互作用（如Cottrell气团和Suzuki气团的形成原理）。此外，题目还要求考生能够区分BCC和FCC金属中不同的强化机制，并解释其对位错运动的影响。这种题目需要考生具备扎实的材料科学基础和综合分析能力，能够将多个复杂概念联系起来进行推理分析，因此在选择题型中属于最高难度等级。", "convertible": true, "correct_option": "Solid solution strengthening occurs when alloying atoms dissolved in the lattice interstices or lattice points, due to their different sizes compared to the matrix atoms, create stress fields that hinder dislocation movement. Examples include Cottrell atmospheres and Suzuki atmospheres. The former refers to interstitial atoms preferentially distributing in the tensile stress region of edge dislocations in BCC metals, pinning the dislocations. The latter involves alloying elements preferentially distributing in the stacking fault regions of extended dislocations in FCC metals, reducing stacking fault energy, expanding the stacking fault region, and making the slip of extended dislocations more difficult.", "choice_question": "Which of the following correctly describes solid solution strengthening and provides examples?", "conversion_reason": "The original short answer question asks for an explanation of a standard concept (solid solution strengthening) and provides specific examples. This can be converted into a multiple-choice question by presenting the detailed explanation as one of the options and asking which option correctly describes the concept and examples.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening occurs when alloying atoms dissolved in the lattice interstices or lattice points, due to their different sizes compared to the matrix atoms, create stress fields that hinder dislocation movement. Examples include Cottrell atmospheres and Suzuki atmospheres.", "B": "Solid solution strengthening is primarily caused by the formation of coherent precipitates that impede dislocation motion, as seen in age-hardened aluminum alloys like Al-Cu systems.", "C": "The effectiveness of solid solution strengthening depends mainly on the difference in electronegativity between solute and solvent atoms, with larger differences creating stronger electrostatic barriers to dislocation glide.", "D": "In solid solution strengthening, the key mechanism is the reduction of grain boundary mobility through solute segregation, analogous to the Zener pinning effect observed in second-phase particles." }, "correct_answer": "A", "explanation": "Option A correctly describes the atomic-scale mechanism of solid solution strengthening through lattice strain fields and provides accurate examples of dislocation-solute interactions. Option B incorrectly describes precipitation hardening instead of solid solution strengthening. Option C uses an intuitive but incorrect electronegativity argument that actually describes solution hardening in ionic crystals rather than metallic alloys. Option D confuses solid solution strengthening with grain boundary pinning effects, a common misconception in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 716, "question": "The ratio of the intercepts of a crystal plane on the three coordinate axes must be a simple integer ratio", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查晶体学中晶面截距比的基本概念，属于基础知识的记忆和理解层面，不需要复杂的应用或分析。 | 难度: 该题目属于基础概念正误判断，仅需记忆晶体平面截距比的基本定义即可作答，无需理解或分析复杂概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "√", "choice_question": "The ratio of the intercepts of a crystal plane on the three coordinate axes must be a simple integer ratio", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In crystallography, the Miller indices of a plane are always inversely proportional to the actual intercepts of that plane with the crystallographic axes.", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "This statement is true because Miller indices are defined as the reciprocals of the fractional intercepts that the plane makes with the crystallographic axes, reduced to the smallest integers. A common misconception is that the indices directly represent the intercepts rather than their reciprocals. The 'always' in this case is correctly used because this is a fundamental definition in crystallography.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3848, "question": "For an Fe-0.35% C alloy, determine the composition and amount of each phase present at 728°C.", "answer": "α: 0.0218% C, 56.1% γ: 0.77% C, 43.9%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算确定Fe-0.35% C合金在728°C时各相的组成和含量，需要使用相图和杠杆定律进行数值计算。答案给出了具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用杠杆定律进行多步计算，涉及相图分析和成分确定，需要概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图的基本概念，能够正确识别728°C时的相组成（α和γ相），并运用杠杆定律进行计算。虽然题目给出了正确选项，但解题过程涉及多个步骤和概念的综合运用，包括相图解读、成分确定和百分比计算，这些都需要一定的材料科学基础和分析能力。", "convertible": true, "correct_option": "α: 0.0218% C, 56.1% γ: 0.77% C, 43.9%", "choice_question": "For an Fe-0.35% C alloy at 728°C, the composition and amount of each phase present is:", "conversion_reason": "The answer is a specific and deterministic result, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "α: 0.0218% C, 56.1% γ: 0.77% C, 43.9%", "B": "α: 0.35% C, 43.9% γ: 0.77% C, 56.1%", "C": "α: 0.0218% C, 43.9% γ: 0.77% C, 56.1%", "D": "α: 0.77% C, 56.1% γ: 0.0218% C, 43.9%" }, "correct_answer": "A", "explanation": "The correct answer uses the lever rule at the eutectoid temperature (728°C) where the α phase contains the minimum carbon content (0.0218%) and γ phase contains the eutectoid composition (0.77%). Option B reverses the phase percentages while keeping compositions correct, exploiting the common lever rule calculation error. Option C maintains correct compositions but reverses the percentages, creating a plausible-looking but incorrect distribution. Option D completely swaps the phase compositions while keeping percentages similar to the correct answer, targeting confusion between phase characteristics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 477, "question": "3. In solid-state crystals, diffusion can be classified into which two types based on whether new phase structures are formed during atomic diffusion?", "answer": "Atomic diffusion and reactive diffusion", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和论述扩散的分类，答案需要文字描述而非选择或判断 | 知识层次: 题目考查对固态晶体中扩散类型的基本分类记忆，属于基础概念的记忆和理解层面 | 难度: 在选择题型中，该题目仅考察对固态晶体扩散分类的基础概念记忆，属于最基础的定义简答类型。题目直接给出两种扩散类型的名称（原子扩散和反应扩散），不需要进行概念解释或复杂分析，只需识别正确分类即可。这种题目在选择题中属于最低难度级别。", "convertible": true, "correct_option": "Atomic diffusion and reactive diffusion", "choice_question": "In solid-state crystals, diffusion can be classified into which two types based on whether new phase structures are formed during atomic diffusion?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by presenting the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Atomic diffusion and reactive diffusion", "B": "Interstitial diffusion and vacancy diffusion", "C": "Self-diffusion and hetero-diffusion", "D": "Thermal diffusion and chemical diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because the question specifically asks about classification based on whether new phase structures are formed. Atomic diffusion occurs without phase change, while reactive diffusion involves new phase formation. Option B is incorrect as it classifies by diffusion mechanism rather than phase formation. Option C is a common confusion between diffusion classifications by atomic species. Option D describes driving forces rather than phase formation effects, creating a multi-level verification trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4130, "question": "To what temperature would 23.0kg of some material at 100^{\\circ} C be raised if 255kJ of heat is supplied? Assume a C_{p} value of 423 J/ kg-K for this material.\n(A) 26.2^{\\circ} C\n(B) 73.8^{\\circ} C\n(C) 126^{\\circ} C\n(D) 152^{\\circ} C", "answer": "the final temperature is 126^{\\circ} C, which corresponds to answer C.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案，提供了四个选项（A、B、C、D）并给出了最终答案对应的选项。 | 知识层次: 题目涉及基本的热力学公式应用（Q = mC_pΔT），只需要直接套用公式进行简单计算即可得出答案，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接套用基本公式（Q = m*Cp*ΔT）并进行简单计算即可得出答案。解题步骤清晰且直接，无需公式变形或多步骤推理，符合等级2的简单公式选择和应用标准。", "convertible": true, "correct_option": "C", "choice_question": "To what temperature would 23.0kg of some material at 100^{\\circ} C be raised if 255kJ of heat is supplied? Assume a C_{p} value of 423 J/ kg-K for this material.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format. The correct option is clearly identified as C.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dislocation density would decrease due to dynamic recovery", "B": "The yield strength would increase linearly with strain", "C": "Twinning would become the dominant deformation mechanism", "D": "The material would undergo a phase transformation to BCC structure" }, "correct_answer": "A", "explanation": "During cold working of pure copper, dynamic recovery occurs at room temperature, leading to dislocation rearrangement and partial annihilation (A is correct). B is wrong because yield strength increases non-linearly with strain due to work hardening saturation. C is incorrect as twinning requires much lower temperatures in copper. D is a trap based on confusing copper with metals that undergo stress-induced phase transformations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1310, "question": "When a spherical embryo with radius $r$ appears in an undercooled liquid, the resulting critical nucleus radius is (3).", "answer": "$\\\\frac{-2\\\\sigma}{\\\\Delta G_{V}}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过公式计算临界核半径，答案是一个具体的数学表达式，需要应用材料科学中的相关公式进行计算。 | 知识层次: 题目考查基本公式的直接应用，仅需将给定的临界核半径公式套用即可，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求直接应用临界核半径公式 $r^* = \\frac{-2\\sigma}{\\Delta G_V}$，无需进行额外的推导或组合多个公式。学生只需识别并正确套用该基本公式即可得出答案，解题步骤简单直接。", "convertible": true, "correct_option": "$\\frac{-2\\sigma}{\\Delta G_{V}}$", "choice_question": "When a spherical embryo with radius $r$ appears in an undercooled liquid, the resulting critical nucleus radius is:", "conversion_reason": "The answer is a specific mathematical expression, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "$\\frac{-2\\sigma}{\\Delta G_{V}}$", "B": "$\\frac{2\\sigma T_{m}}{\\Delta H_{f} \\Delta T}$", "C": "$\\sqrt{\\frac{3\\sigma}{\\Delta G_{V}}}$", "D": "$\\frac{\\sigma}{2\\Delta G_{V}}$" }, "correct_answer": "A", "explanation": "The correct answer A is derived from the Gibbs-Thomson equation where the critical nucleus radius balances surface energy ($\\sigma$) and volumetric free energy ($\\Delta G_V$). Option B uses the correct numerator but incorrectly substitutes $\\Delta G_V$ with $\\Delta H_f \\Delta T/T_m$, exploiting the common confusion between these thermodynamic parameters. Option C mimics the form of stress concentration equations, targeting those who mechanically apply sqrt(3) factors. Option D halves the correct denominator, a typical error when misremembering the Gibbs-Thomson coefficient. These distractors exploit: 1) thermodynamic parameter substitution (B), 2) mechanical analogy fallacy (C), and 3) coefficient memorization error (D).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2478, "question": "A copper block subjected to large cold deformation has a stored energy of 2×10^5 J·m^-3, and the typical value of high-angle boundary energy is 0.5 J·m^-2. According to the classical homogeneous nucleation theory, what is the critical nucleus size for recrystallization?", "answer": "According to classical nucleation theory, the critical nucleus radius r* = 2γ/ΔG, where γ is the boundary energy and ΔG is the stored energy per unit volume. Substituting the boundary energy and stored energy, we obtain r* = (2×0.5)/(2×10^5) m = 5×10^-7 m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据给定的公式和数据进行数值计算，最终得出一个具体的数值结果（临界核尺寸）。解答过程涉及公式应用和单位换算，符合计算题的特征。 | 知识层次: 题目主要涉及经典均质形核理论的基本公式应用，即通过给定的边界能和储存能直接套用公式计算临界核尺寸。虽然需要理解相关概念，但计算过程简单直接，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（r* = 2γ/ΔG）并进行简单的数值代入计算。解题步骤非常直接，无需多个公式组合或复杂的概念理解，属于最基础的难度等级。", "convertible": true, "correct_option": "5×10^-7 m", "choice_question": "A copper block subjected to large cold deformation has a stored energy of 2×10^5 J·m^-3, and the typical value of high-angle boundary energy is 0.5 J·m^-2. According to the classical homogeneous nucleation theory, what is the critical nucleus size for recrystallization?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5×10^-7 m", "B": "2.5×10^-6 m", "C": "1×10^-7 m", "D": "1×10^-6 m" }, "correct_answer": "A", "explanation": "The critical nucleus size (r*) is calculated using the equation r* = 2γ/ΔG, where γ is the high-angle boundary energy and ΔG is the stored energy. Plugging in the values: r* = 2×0.5/2×10^5 = 5×10^-7 m. Option B is derived by forgetting to divide by 2 in the numerator. Option C results from incorrectly using 1 J·m^-2 for boundary energy. Option D comes from a unit conversion error between J·m^-3 and J·m^-2.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3731, "question": "An aluminum alloy that has a plane strain fracture toughness of 25,000 psi \\sqrt{m}. fails when a stress of 42,000 psi is applied. Observation of the fracture surface indicates that fracture began at the surface of the part. Estimate the size of the flaw that initiated fracture. Assume that f=1.1.", "answer": "the size of the flaw that initiated fracture is 0.093 \\text{ in}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过公式计算来估计缺陷的尺寸，涉及数值计算和材料科学中的断裂力学知识。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用断裂力学中的公式进行多步计算，涉及平面应变断裂韧性和应力强度的概念关联，并需要综合分析给定的参数来估算缺陷尺寸。虽然计算过程相对直接，但需要理解公式中各参数的含义及其相互关系，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解断裂韧性和应力强度的概念，并应用相关公式进行多步计算。题目要求考生能够综合分析给定参数（断裂韧性、应力、几何因子）并正确代入公式求解缺陷尺寸，涉及中等应用层次的知识和计算能力。", "convertible": true, "correct_option": "0.093 in", "choice_question": "An aluminum alloy with a plane strain fracture toughness of 25,000 psi √m fails under a stress of 42,000 psi, with fracture initiating at the surface. Assuming f=1.1, estimate the size of the flaw that initiated fracture.", "conversion_reason": "The calculation yields a specific numerical answer, making it suitable for conversion into a multiple-choice question format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.093 in", "B": "0.042 in", "C": "0.125 in", "D": "0.067 in" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula for critical flaw size in fracture mechanics: a_c = (K_IC/(f*σ))^2/π. Plugging in K_IC=25,000 psi√in, σ=42,000 psi, and f=1.1 gives 0.093 in. Option B is a common error from incorrectly using the stress value directly. Option C results from forgetting to square the denominator. Option D comes from miscalculating the geometric factor f.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4512, "question": "For the following pair of polymers, do the following: (1) state whether or not it is possible to decide whether one polymer has a higher tensile strength than the other; (2) if this is possible, note which has the higher tensile strength and then cite the reason(s) for your choice; and (3) if it is not possible to decide, then state why. Network polyester; lightly branched polypropylene", "answer": "Yes it is possible. The network polyester will display a greater tensile strength. Relative chain motion is much more restricted than for the lightly branched polypropylene since there are many more of the strong covalent bonds for the network structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对两种聚合物的拉伸强度进行比较，并解释原因，需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目要求对不同聚合物的拉伸强度进行比较，并解释原因。这需要理解聚合物结构（网络结构与轻度支化结构）对力学性能的影响，属于概念关联和综合分析。虽然不涉及复杂计算，但需要对材料性能与结构关系有较深入的理解。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生不仅能够识别两种聚合物的结构差异（网络聚酯与轻度支化聚丙烯），还需要理解这些结构如何影响材料的拉伸强度。此外，考生需要能够将结构特征与力学性能联系起来，并做出明确的判断。虽然题目提供了明确的比较点，但仍需要一定的综合分析能力来正确回答。", "convertible": true, "correct_option": "The network polyester will display a greater tensile strength.", "choice_question": "For the following pair of polymers, which one has a higher tensile strength: Network polyester or lightly branched polypropylene?", "conversion_reason": "The original question asks for a comparison between two polymers in terms of tensile strength, and the answer provides a clear choice with justification. This can be effectively converted into a multiple-choice format by presenting the two polymers as options and using the given answer as the correct choice.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Network polyester due to its crosslinked structure restricting chain mobility", "B": "Lightly branched polypropylene because branching increases crystallinity", "C": "They have comparable tensile strength as both are thermoplastics", "D": "Cannot be determined without knowing the exact degree of branching" }, "correct_answer": "A", "explanation": "The correct answer is A because network polymers' covalent crosslinks provide superior tensile strength by preventing chain slippage. B is incorrect as branching typically reduces crystallinity in polypropylene. C is wrong as network polyester is actually a thermoset. D is a strong distractor that exploits AI's tendency to defer judgment when branching parameters are mentioned, but the fundamental structural difference is decisive here.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2195, "question": "Why is the compressive strength of ceramics always higher than the tensile strength?", "answer": "The compressive strength of ceramics is generally about 15 times the tensile strength. This is because under tension, when a crack reaches the critical size, it becomes unstable and propagates rapidly, leading to fracture; whereas under compression, cracks either close or propagate steadily and slowly, turning parallel to the compression axis. In other words, under tension, the tensile strength of ceramics is determined by the maximum crack size in the crystal, while the compressive strength is determined by the average size of the cracks.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么陶瓷的抗压强度总是高于抗拉强度，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释陶瓷压缩强度高于拉伸强度的机理，涉及裂纹在不同应力状态下的行为差异和传播机制的分析，需要综合运用材料科学中的断裂力学知识，进行推理和解释。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解陶瓷材料的基本力学性能差异，还需要深入掌握裂纹扩展的微观机理及其在不同应力状态下的行为差异。正确选项涉及复杂的材料断裂力学原理，包括临界裂纹尺寸、裂纹不稳定传播条件以及压缩与拉伸状态下裂纹行为的对比分析。这需要考生具备综合运用材料科学和力学知识的能力，能够进行高阶推理和机理解释，远超选择题型中常见的简单概念识别或记忆性内容。", "convertible": true, "correct_option": "The compressive strength of ceramics is generally about 15 times the tensile strength. This is because under tension, when a crack reaches the critical size, it becomes unstable and propagates rapidly, leading to fracture; whereas under compression, cracks either close or propagate steadily and slowly, turning parallel to the compression axis. In other words, under tension, the tensile strength of ceramics is determined by the maximum crack size in the crystal, while the compressive strength is determined by the average size of the cracks.", "choice_question": "Why is the compressive strength of ceramics always higher than the tensile strength?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Compressive stresses cause crack closure while tensile stresses promote crack propagation", "B": "Ceramics have higher elastic modulus in compression than in tension", "C": "The covalent bonds in ceramics are stronger under compressive loading", "D": "Grain boundaries in ceramics provide better resistance to compression than tension" }, "correct_answer": "A", "explanation": "The correct answer is A because compressive stresses cause cracks to close or propagate parallel to the loading direction, while tensile stresses open cracks perpendicular to the loading direction leading to rapid failure. Option B is incorrect because elastic modulus is a material property independent of loading direction. Option C is a trap because while covalent bonds are strong, their strength doesn't vary significantly with loading type. Option D is misleading because grain boundaries actually weaken ceramics in both tension and compression.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3717, "question": "An aluminum plate 0.5 cm thick is to withstand a force of 50,000N with no permanent deformation. If the aluminum has a yield strength of 125 MPa, what is the minimum width of the plate?", "answer": "the minimum width of the plate is 8 cm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解最小宽度，涉及力学性能参数和基本力学公式的使用。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目涉及基本公式应用（应力=力/面积）和简单计算（根据已知条件求解最小宽度），不需要多步计算或复杂分析，属于直接套用公式的简单应用层次。 | 难度: 在选择题中属于简单应用难度，需要理解屈服强度的概念并应用基本公式（应力=力/面积）进行计算，但不需要多个公式组合或复杂分析。", "convertible": true, "correct_option": "8 cm", "choice_question": "An aluminum plate 0.5 cm thick is to withstand a force of 50,000N with no permanent deformation. If the aluminum has a yield strength of 125 MPa, what is the minimum width of the plate?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8 cm", "B": "4 cm", "C": "16 cm", "D": "2 cm" }, "correct_answer": "A", "explanation": "The correct answer is calculated by dividing the force (50,000N) by the product of yield strength (125 MPa) and thickness (0.5 cm), then converting units appropriately. Option B is a cognitive bias trap where one might forget to convert MPa to Pa. Option C exploits the common mistake of using elastic modulus instead of yield strength. Option D is designed to catch those who incorrectly divide thickness by force.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4606, "question": "Do all electrons have a net magnetic moment? Why or why not?", "answer": "Each electron will have a net magnetic moment from spin, and possibly, orbital contributions, which do not cancel for an isolated atom.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释为什么所有电子是否具有净磁矩，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查电子磁矩的基本概念，主要涉及自旋和轨道贡献的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 该题目在选择题型中属于中等难度。虽然问题涉及基础概念（电子磁矩），但需要考生理解并区分自旋磁矩和轨道磁矩的贡献，并知道它们在孤立原子中的表现。这超出了简单的定义记忆（等级1），但又不涉及复杂的概念体系分析（等级3）。正确选项明确指出了关键点，使得题目在选择题型中属于概念解释和描述级别。", "convertible": true, "correct_option": "Each electron will have a net magnetic moment from spin, and possibly, orbital contributions, which do not cancel for an isolated atom.", "choice_question": "Do all electrons have a net magnetic moment?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, all electrons have a net magnetic moment due to their intrinsic spin", "B": "No, only unpaired electrons in partially filled orbitals have a net magnetic moment", "C": "Only when electrons are in a magnetic field do they acquire a net magnetic moment", "D": "No, the magnetic moments of paired electrons always cancel out completely" }, "correct_answer": "A", "explanation": "The correct answer is A because every electron has an intrinsic spin magnetic moment, and in isolated atoms there may also be orbital contributions that don't cancel. Option B is a common misconception that only applies to collective systems where pairing occurs. Option C incorrectly suggests magnetic moments are field-induced rather than intrinsic. Option D is a trap based on overgeneralizing the concept of paired electrons in molecules/solids to isolated electrons.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3124, "question": "Explain the basic concept and terminology: Superstructure", "answer": "Superstructure: The lattice constant of an ordered solid solution differs from that of a disordered solid solution, resulting in additional diffraction lines on the X-ray diffraction pattern, known as superstructure lines. Therefore, an ordered solid solution is also referred to as a superstructure or superlattice.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释基本概念和术语，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对\"Superstructure\"这一基本概念的定义和术语的记忆和理解，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求解释\"Superstructure\"的基本概念和术语，正确选项提供了明确的定义和相关的X射线衍射现象描述。虽然涉及一些专业术语（如\"lattice constant\"、\"ordered solid solution\"等），但整体上是对单一概念的阐述，不需要进行复杂的概念体系分析或比较。在选择题型内，这属于中等难度，比简单定义记忆（等级1）要求更高，但比需要处理多个相互关联概念的题目（等级3）要简单。", "convertible": true, "correct_option": "Superstructure: The lattice constant of an ordered solid solution differs from that of a disordered solid solution, resulting in additional diffraction lines on the X-ray diffraction pattern, known as superstructure lines. Therefore, an ordered solid solution is also referred to as a superstructure or superlattice.", "choice_question": "Which of the following correctly describes the concept of Superstructure?", "conversion_reason": "The answer is a standard definition and terminology, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Superstructure refers to the periodic arrangement of atoms in an ordered solid solution that produces additional diffraction lines due to its distinct lattice constant compared to the disordered state", "B": "Superstructure describes the hierarchical organization of crystalline defects that form during rapid solidification processes", "C": "Superstructure denotes the macroscopic arrangement of grains in polycrystalline materials that exhibit preferential orientation", "D": "Superstructure represents the metastable phase configuration achieved through severe plastic deformation techniques" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines superstructure as the ordered arrangement in solid solutions that creates distinct diffraction patterns. Option B exploits confusion with defect structures, Option C misdirects with texture terminology, and Option D traps with severe deformation concepts - all plausible but incorrect associations in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1421, "question": "The type of bonding in a material determines the level of its elastic modulus. What type of bond is present along the molecular chains of polymer materials, and what type of bond exists between the molecular chains, hence how is their elastic modulus?", "answer": "The bonds along the molecular chains of polymer materials are covalent bonds, and the bonds between the molecular chains are molecular bonds, hence their elastic modulus is the lowest.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释聚合物材料中分子链内和分子链间的键类型及其对弹性模量的影响，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对聚合物材料中键合类型及其对弹性模量影响的基础概念记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆（聚合物材料的键类型和弹性模量），但需要考生同时掌握两种不同的键类型（分子链内的共价键和分子链间的分子键）及其对材料性能的影响。这比单纯记忆单一概念的定义（等级1）要求更高，但不需要进行复杂的概念体系阐述或比较分析（等级3）。", "convertible": true, "correct_option": "The bonds along the molecular chains of polymer materials are covalent bonds, and the bonds between the molecular chains are molecular bonds, hence their elastic modulus is the lowest.", "choice_question": "What type of bond is present along the molecular chains of polymer materials, and what type of bond exists between the molecular chains, hence how is their elastic modulus?", "conversion_reason": "The answer is a standard explanation involving specific types of bonds and their effect on elastic modulus, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Covalent bonds along chains, hydrogen bonds between chains - intermediate elastic modulus", "B": "Covalent bonds along chains, van der Waals forces between chains - lowest elastic modulus", "C": "Metallic bonds along chains, ionic bonds between chains - highest elastic modulus", "D": "Ionic bonds along chains, covalent bonds between chains - variable elastic modulus" }, "correct_answer": "B", "explanation": "The correct answer is B because polymers have covalent bonds along their molecular chains (providing chain strength) but only weak van der Waals forces between chains, resulting in the lowest elastic modulus among material classes. Option A is wrong by suggesting hydrogen bonding between chains would create intermediate modulus (true for some biopolymers but not typical synthetic polymers). Option C is completely wrong by proposing metallic/ionic bonding which don't exist in polymers. Option D reverses the bonding types and falsely suggests variable modulus.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 618, "question": "Cold working and hot working", "answer": "Cold working and hot working: Generally distinguished based on the recrystallization temperature of metal materials. Processing above the recrystallization temperature is called hot working, while processing below the recrystallization temperature and at room temperature is called cold working.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对冷加工和热加工进行解释和论述，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对冷加工和热加工的基本定义和分类的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求区分冷加工和热加工的定义，并基于再结晶温度进行区分。虽然涉及基础概念记忆，但需要理解并解释两个加工方式的区别，属于中等难度的选择题。不需要复杂的分析或比较多个概念体系，因此不属于最高难度等级。", "convertible": true, "correct_option": "Generally distinguished based on the recrystallization temperature of metal materials. Processing above the recrystallization temperature is called hot working, while processing below the recrystallization temperature and at room temperature is called cold working.", "choice_question": "How are cold working and hot working generally distinguished?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Based on whether the processing temperature exceeds the material's glass transition temperature", "B": "Determined by the ratio of yield strength to ultimate tensile strength at the processing temperature", "C": "Defined by whether dynamic recrystallization occurs during deformation", "D": "Generally distinguished based on the recrystallization temperature of metal materials" }, "correct_answer": "D", "explanation": "The correct answer is D because cold and hot working are fundamentally distinguished by whether the processing occurs above or below the recrystallization temperature. Option A is a cognitive bias trap using the glass transition temperature concept (relevant for polymers but not metals). Option B exploits material property confusion by creating a plausible-sounding but irrelevant strength ratio criterion. Option C is a professional intuition trap - while recrystallization is key, the 'dynamic' qualifier makes this incorrect for general distinction purposes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2938, "question": "After welding A and A-B alloy, the Kirkendall effect occurs, and the interface is measured to move towards the A sample. Then (A) The diffusion rate of component A is greater than that of component B (B) The opposite of (A) (C) The diffusion rates of components A and B are the same", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从选项（A）、（B）、（C）中选择正确答案 | 知识层次: 题目考查Kirkendall效应的应用，需要理解扩散速率差异对界面移动方向的影响，涉及概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于较高难度，需要理解Kirkendall效应的基本原理，并能将界面移动方向与扩散速率差异进行关联分析。题目要求考生不仅掌握扩散概念，还需要进行逆向推理（从界面移动方向反推扩散速率关系），涉及多步逻辑推理和概念的综合应用。", "convertible": true, "correct_option": "A", "choice_question": "After welding A and A-B alloy, the Kirkendall effect occurs, and the interface is measured to move towards the A sample. Then", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The vacancy flux is dominated by A atoms diffusing into the A-B alloy", "B": "The vacancy flux is dominated by B atoms diffusing into pure A", "C": "The interdiffusion coefficient is negative in this system", "D": "The marker velocity is proportional to the square of the concentration gradient" }, "correct_answer": "A", "explanation": "The Kirkendall effect shows the interface moves towards A, proving A atoms diffuse faster into the A-B alloy than B atoms diffuse out (A correct). Option B reverses the correct diffusion direction, exploiting common confusion about vacancy flux directionality. Option C uses a real but irrelevant concept (negative interdiffusion coefficients occur in spinodal systems, not here). Option D presents a mathematically plausible but physically incorrect relationship, targeting AI's tendency to over-rely on formulaic patterns.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 37, "question": "Calculate the ratio of the number of tetrahedral voids to the number of O2- ions", "answer": "The ratio of the number of tetrahedral voids to the number of O2- ions is 2:1", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算四面体空隙与O2-离子的数量比），答案给出了具体的计算结果（2:1），这符合计算题的特征 | 知识层次: 题目要求计算四面体空隙与O2-离子数量的比值，这属于基本公式应用和简单计算，直接套用晶体结构中的空隙比例知识即可得出结果，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需直接应用基本公式（四面体空隙数与阴离子数的比例关系）进行简单计算，无需复杂推理或多步骤操作。属于单一公式直接计算的类型，因此难度等级为1。", "convertible": true, "correct_option": "2:1", "choice_question": "What is the ratio of the number of tetrahedral voids to the number of O2- ions?", "conversion_reason": "The answer is a specific ratio (2:1), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2:1", "B": "1:1", "C": "1:2", "D": "4:1" }, "correct_answer": "A", "explanation": "The correct answer is A (2:1) because in a close-packed structure, the number of tetrahedral voids is always twice the number of atoms/ions. Option B (1:1) is a cognitive bias trap, exploiting the common misconception that voids and ions might have a one-to-one correspondence. Option C (1:2) reverses the correct ratio to catch those who confuse the order. Option D (4:1) is a professional intuition trap, designed to mislead by suggesting a higher coordination number scenario.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1518, "question": "What type of solid solution is ferrite formed by carbon in α-Fe", "answer": "Interstitial", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述碳在α-Fe中形成的固溶体类型，答案\"Interstitial\"是一个术语，需要简要解释其含义和特点，属于简答题类型。 | 知识层次: 题目考查铁素体(ferrite)中碳在α-Fe中形成的固溶体类型这一基本概念的记忆和理解，属于材料科学中固溶体分类的基础知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即碳在α-Fe中形成的固溶体类型是间隙式（Interstitial）。题目不涉及复杂的概念解释或体系阐述，只需考生记住这一基本分类即可作答，属于最基础的难度等级。", "convertible": true, "correct_option": "Interstitial", "choice_question": "What type of solid solution is ferrite formed by carbon in α-Fe?", "conversion_reason": "The answer is a standard term (Interstitial), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial", "B": "Substitutional", "C": "Intermetallic", "D": "Eutectic" }, "correct_answer": "A", "explanation": "The correct answer is A (Interstitial) because carbon atoms are small enough to occupy the interstitial sites in the BCC lattice of α-Fe. Option B (Substitutional) is a cognitive bias trap - while substitutional solid solutions are common in alloys, carbon is too small to substitute for Fe atoms. Option C (Intermetallic) exploits the tendency to associate 'compound formation' with interstitial solutions, but ferrite is not an intermetallic compound. Option D (Eutectic) is a multi-level trap - while eutectic systems are important in Fe-C alloys, this describes a phase mixture not a solid solution type.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4579, "question": "Explain why no hole is generated by the electron excitation involving a donor impurity atom.", "answer": "No hole is generated by an electron excitation involving a donor impurity atom because the excitation comes from a level within the band gap, and thus, no missing electron is created within the normally filled valence band.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么在涉及施主杂质原子的电子激发过程中不会产生空穴，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释电子激发过程中空穴不产生的原因，涉及能带理论、杂质能级和电子跃迁机理的综合分析，需要深入理解半导体物理中的相关概念并进行逻辑推理。 | 难度: 在选择题中属于最高难度等级，题目要求深入理解半导体物理中的杂质能级和电子激发机制，需要综合运用能带理论、掺杂效应和载流子生成原理进行复杂分析。正确选项涉及从带隙内能级激发的特殊性质，以及价带完整性保持的机理解释，这超出了基础概念记忆和简单应用层面，属于需要全面分析复杂现象的题目类型。", "convertible": true, "correct_option": "No hole is generated by an electron excitation involving a donor impurity atom because the excitation comes from a level within the band gap, and thus, no missing electron is created within the normally filled valence band.", "choice_question": "Why is no hole generated by the electron excitation involving a donor impurity atom?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The excitation originates from an impurity level within the band gap, leaving no vacancy in the valence band", "B": "Donor impurities introduce excess electrons that compensate for any potential holes", "C": "The energy required for excitation is too low to create electron-hole pairs", "D": "Impurity atoms prevent the formation of holes through quantum confinement effects" }, "correct_answer": "A", "explanation": "Correct answer A explains that donor levels reside in the band gap, so excitation doesn't create a valence band vacancy. Option B misleads by suggesting compensation effect (a real but irrelevant phenomenon). Option C exploits the common misconception about excitation energy thresholds. Option D uses advanced terminology (quantum confinement) in an incorrect context to sound plausible.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 98, "question": "For edge dislocations, what are the characteristics of the dislocation line direction, Burgers vector, and dislocation motion direction?", "answer": "Edge dislocation: the dislocation line is perpendicular to the Burgers vector, and the dislocation line is perpendicular to the direction of dislocation motion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释边缘位错的特性，包括位错线方向、Burgers矢量和位错运动方向之间的关系，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查边缘位错的基本特征，包括位错线方向、伯格斯矢量和位错运动方向之间的关系，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（位错线方向、伯格斯矢量、位错运动方向的关系），但需要考生准确记忆并区分边缘位错的三个关键特征之间的相互关系。这比单纯复述定义（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。正确选项明确给出了边缘位错的两个垂直关系，考生只需识别这些特征即可作答。", "convertible": true, "correct_option": "the dislocation line is perpendicular to the Burgers vector, and the dislocation line is perpendicular to the direction of dislocation motion", "choice_question": "For edge dislocations, which of the following correctly describes the characteristics of the dislocation line direction, Burgers vector, and dislocation motion direction?", "conversion_reason": "The answer is a standard description of the characteristics of edge dislocations, which can be converted into a multiple-choice format by presenting it as one of several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dislocation line is perpendicular to both the Burgers vector and the direction of motion", "B": "The dislocation line is parallel to the Burgers vector and perpendicular to the direction of motion", "C": "The dislocation line is perpendicular to the Burgers vector and parallel to the direction of motion", "D": "All three vectors (dislocation line, Burgers vector, motion direction) are mutually perpendicular" }, "correct_answer": "A", "explanation": "For edge dislocations, the correct relationship is that the dislocation line is perpendicular to both the Burgers vector and the direction of motion. Option B mimics screw dislocation behavior, creating a common confusion. Option C reverses the correct relationship, exploiting surface-level similarity. Option D introduces an impossible geometric configuration that might seem plausible due to the 'mutually perpendicular' phrasing. Advanced AI systems may overgeneralize from screw dislocation characteristics or misapply vector geometry principles.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2325, "question": "According to solidification theory, how does adding a nucleating agent refine the grains of a casting?", "answer": "After adding a nucleating agent, it can promote heterogeneous nucleation in the undercooled liquid. This not only increases the substrates required for heterogeneous nucleation but also reduces the critical nucleus radius, both of which will increase the number of nuclei, thereby refining the grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释添加成核剂如何细化铸件晶粒，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释添加成核剂如何细化铸件晶粒的机理，涉及凝固理论中的异质成核、临界晶核半径等概念的综合运用和推理分析，需要深入理解并关联多个知识点进行解释。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解凝固理论的基本概念（如异质形核、临界晶核半径等），还需要综合运用这些知识分析成核剂对晶粒细化的影响机制。正确选项涉及多个关键步骤的推理（增加形核基底→降低临界晶核半径→增加形核数量→细化晶粒），且需要将热力学（临界半径）与动力学（形核率）因素结合分析。这种对复杂机理的深度解释和综合推理能力要求，远超选择题常见的概念识别或简单应用层次。", "convertible": true, "correct_option": "After adding a nucleating agent, it can promote heterogeneous nucleation in the undercooled liquid. This not only increases the substrates required for heterogeneous nucleation but also reduces the critical nucleus radius, both of which will increase the number of nuclei, thereby refining the grains.", "choice_question": "According to solidification theory, how does adding a nucleating agent refine the grains of a casting?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The nucleating agent increases the undercooling required for nucleation, leading to more simultaneous nucleation events", "B": "The agent provides additional surfaces for heterogeneous nucleation while reducing the critical nucleus radius, increasing nucleation density", "C": "It preferentially absorbs solute atoms at the solid-liquid interface, creating constitutional undercooling that fragments growing dendrites", "D": "The agent modifies the liquid structure to increase viscosity, slowing crystal growth and allowing more nucleation sites to activate" }, "correct_answer": "B", "explanation": "Correct answer B describes the dual mechanism of providing nucleation sites and reducing critical radius. Option A incorrectly reverses the undercooling effect - nucleating agents actually reduce required undercooling. Option C describes dendrite fragmentation which is a different grain refinement mechanism. Option D introduces viscosity effects which are irrelevant to nucleation-stage grain refinement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4795, "question": "What is the magnitude of the maximum stress that exists at the tip of an internal crack having a radius of curvature of 1.9 × 10^{-4} mm\\left(7.5 × 10^{-6} in.\\right) and a crack length of 3.8 × 10^{-2} mm\\left(1.5 × 10^{-3}\\right. in.) when a tensile stress of 140 MPa(20,000 psi) is applied?", "answer": "the magnitude of the maximum stress is 2800 \\text{ mpa} (400,000 \\text{ psi}).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算裂纹尖端最大应力的大小，需要应用相关公式进行数值计算，答案是一个具体的数值结果。 | 知识层次: 题目涉及多步计算和公式应用，需要理解应力集中概念并正确应用相关公式进行计算，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解应力集中概念、掌握裂纹尖端应力计算公式，并进行多步单位换算和数值计算。虽然题目提供了公式所需的所有参数，但计算过程涉及指数运算和单位转换，对学生的应用能力和计算准确性有较高要求。", "convertible": true, "correct_option": "2800 MPa (400,000 psi)", "choice_question": "What is the magnitude of the maximum stress that exists at the tip of an internal crack having a radius of curvature of 1.9 × 10^{-4} mm (7.5 × 10^{-6} in.) and a crack length of 3.8 × 10^{-2} mm (1.5 × 10^{-3} in.) when a tensile stress of 140 MPa (20,000 psi) is applied?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2800 MPa (400,000 psi)", "B": "1400 MPa (200,000 psi)", "C": "5600 MPa (800,000 psi)", "D": "700 MPa (100,000 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A (2800 MPa) calculated using the stress concentration formula σ_m = 2σ_0√(a/ρ_t), where σ_0=140 MPa, a=1.9×10^-2 mm (half crack length), ρ_t=1.9×10^-4 mm. Option B is half the correct value, exploiting the common mistake of omitting the factor of 2 in the formula. Option C doubles the correct answer, targeting those who might incorrectly square the stress concentration factor. Option D is the applied stress itself, preying on the misconception that stress concentration doesn't significantly amplify the nominal stress.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3528, "question": "What is the difference between natural aging and artificial aging of aluminum alloys?", "answer": "The process of spontaneous strengthening of the alloy at room temperature is called natural aging, while the aging process carried out at a certain heating temperature is called artificial aging.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释自然时效和人工时效的区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对自然时效和人工时效的基本定义和区别的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目要求考生区分自然时效和人工时效的定义，属于概念解释和描述的层次。虽然需要记忆两个不同的定义，但不需要复杂的分析或比较多个概念体系，因此属于中等难度。", "convertible": true, "correct_option": "The process of spontaneous strengthening of the alloy at room temperature is called natural aging, while the aging process carried out at a certain heating temperature is called artificial aging.", "choice_question": "What is the difference between natural aging and artificial aging of aluminum alloys?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Natural aging occurs at room temperature while artificial aging requires elevated temperatures", "B": "Natural aging strengthens the alloy through dislocation movement while artificial aging uses precipitation hardening", "C": "Natural aging is a reversible process while artificial aging causes permanent microstructural changes", "D": "Natural aging takes weeks to complete while artificial aging achieves similar results in hours" }, "correct_answer": "A", "explanation": "Correct answer A precisely distinguishes the temperature difference between the two processes. Option B incorrectly ascribes different strengthening mechanisms - both processes actually rely on precipitation hardening. Option C reverses the reversibility concept - artificial aging is more reversible than natural aging. Option D's time comparison is misleading as the fundamental difference is temperature, not duration.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 752, "question": "As a result of what reason, 'compositional defects' are inevitably produced in the crystal structure?", "answer": "Doping of non-equivalent ions", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释“compositional defects”产生的原因，需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查的是对\"compositional defects\"产生原因的基础概念记忆和理解，只需要回答掺杂非等价离子这一基本原理即可，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目直接询问晶体结构中\"compositional defects\"产生的原因，正确选项\"Doping of non-equivalent ions\"是该缺陷的标准定义性答案，无需复杂推理或概念比较。学生只需记住基础概念即可作答，符合选择题型中最基础的知识记忆要求。", "convertible": true, "correct_option": "Doping of non-equivalent ions", "choice_question": "As a result of what reason, 'compositional defects' are inevitably produced in the crystal structure?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermal vibration of atoms at equilibrium positions", "B": "Dislocation movement during plastic deformation", "C": "Vacancy diffusion in high-temperature annealing", "D": "Doping of non-equivalent ions" }, "correct_answer": "D", "explanation": "The correct answer is D because compositional defects specifically arise from the introduction of foreign atoms with different valencies (non-equivalent ions) into the crystal lattice. Option A describes point defects (phonons), not compositional defects. Option B refers to line defects caused by mechanical deformation. Option C describes vacancy-mediated diffusion processes that don't alter the overall composition. These distractors exploit common confusions between different defect types in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4054, "question": "Most polymers and ionic ceramics have energy band gap structures that are most similar to those of(a) Insulators(b) Semiconductors(c) Metals", "answer": "Most polymers and ionic ceramics have wide energy band gaps; thus, they are most like those of insulators.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项(a)、(b)、(c)中选择最符合描述的答案 | 知识层次: 题目考查对材料能带结构分类的基本概念记忆和理解，属于基础概念记忆性知识 | 难度: 该题目属于基础概念记忆类型，仅需识别和回忆聚合物和离子陶瓷的能带结构特点，直接对应到绝缘体的定义。选择题型中无需复杂分析或比较，属于最简单的概念识别层次。", "convertible": true, "correct_option": "(a) Insulators", "choice_question": "Most polymers and ionic ceramics have energy band gap structures that are most similar to those of", "conversion_reason": "原题目已经是选择题格式，且答案明确对应一个选项，可以直接转换为单选题。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress for slip in FCC metals", "B": "The Peierls-Nabarro stress for dislocation motion in BCC metals", "C": "The theoretical shear strength of a perfect crystal", "D": "The stress required for twinning in HCP metals" }, "correct_answer": "A", "explanation": "The correct answer is A because the question specifically asks about the minimum stress required to initiate plastic deformation in annealed FCC metals, which is governed by the critical resolved shear stress for slip. Option B is a strong distractor because it involves dislocation motion but applies to BCC metals. Option C is a theoretical maximum that is much higher than practical values. Option D exploits the common confusion between slip and twinning mechanisms in HCP systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3849, "question": "For an Fe-0.35% C alloy, determine the composition and amount of each phase present at 726°C.", "answer": "α: 0.0218% C, 93.3% Fe3C: 6.67% C, 4.9%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算确定合金中各相的组成和含量，需要使用杠杆法则等计算方法，答案以具体数值形式呈现，符合计算题的特征。 | 知识层次: 题目需要应用杠杆定律进行多步计算，涉及相图分析和成分转换，属于中等应用层次。虽然计算过程相对直接，但需要理解相图的基本原理和正确应用公式。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图的基本概念，能够正确识别726°C时的相组成（α相和Fe3C相），并运用杠杆定律进行多步计算。虽然题目提供了正确选项，但解题过程涉及相图定位、成分确定和百分比计算等多个步骤，需要较强的概念关联和综合分析能力。相比简单的概念识别题（等级1）或单一计算题（等级2），该题目对知识掌握深度和计算准确性的要求更高，但尚未达到复杂多变量计算（等级4）的程度。", "convertible": true, "correct_option": "α: 0.0218% C, 93.3% Fe3C: 6.67% C, 4.9%", "choice_question": "For an Fe-0.35% C alloy at 726°C, what is the composition and amount of each phase present?", "conversion_reason": "The answer is a specific and deterministic result, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "α: 0.0218% C, 93.3%; Fe3C: 6.67% C, 4.9%", "B": "α: 0.35% C, 95.1%; Fe3C: 6.67% C, 4.9%", "C": "γ: 0.77% C, 45.6%; Fe3C: 6.67% C, 54.4%", "D": "α: 0.0218% C, 95.1%; Fe3C: 6.67% C, 4.9%" }, "correct_answer": "A", "explanation": "正确答案A使用了正确的杠杆定律计算，在726°C时α相含碳量为0.0218%，Fe3C为6.67%。干扰项B错误地将整体成分作为α相成分，是典型的成分混淆陷阱。干扰项C引入了不存在的γ相，利用高温相的记忆干扰。干扰项D在计算相比例时错误，是常见的计算错误陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2205, "question": "For metals and alloys that do not undergo phase transformations in the solid state, can their grain size be changed without remelting? What methods can be used to alter it?", "answer": "Yes. It can be achieved through cold deformation followed by recrystallization annealing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述如何在不重新熔化的条件下改变金属和合金的晶粒尺寸，答案提供了文字解释和具体方法，符合简答题的特征。 | 知识层次: 题目需要理解金属和合金的晶粒尺寸变化机制，并应用冷变形和再结晶退火的概念来解决问题。这涉及多步思考（冷变形和再结晶退火两个步骤）和概念关联（将塑性变形与热处理工艺联系起来），但不需要复杂的机理分析或创新设计。 | 难度: 在选择题中属于中等难度，需要理解金属和合金的晶粒尺寸变化原理，并关联冷变形和再结晶退火两个工艺步骤的作用。虽然不涉及多步计算，但需要综合分析材料加工工艺对微观结构的影响，属于概念关联和综合分析层次。", "convertible": true, "correct_option": "Yes. It can be achieved through cold deformation followed by recrystallization annealing.", "choice_question": "For metals and alloys that do not undergo phase transformations in the solid state, can their grain size be changed without remelting? What methods can be used to alter it?", "conversion_reason": "The answer is a standard and concise statement, making it suitable for conversion into a multiple-choice format where this statement can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cold deformation followed by recrystallization annealing", "B": "Direct isothermal holding at 0.9Tm for extended periods", "C": "Applying high-frequency ultrasonic vibration during solidification", "D": "Controlled martensitic transformation through rapid quenching" }, "correct_answer": "A", "explanation": "Correct answer A involves the only valid method for grain refinement without phase transformation or remelting. Option B exploits the common misconception about grain growth at high temperatures, ignoring that 0.9Tm would cause grain coarsening rather than refinement. Option C uses a real technique (ultrasonic refinement) but incorrectly applies it to solid-state processing instead of solidification. Option D introduces a completely irrelevant phase transformation mechanism that doesn't apply to the given condition of no solid-state phase changes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3345, "question": "Among the various types of steel currently used in industry, cold-drawn high-carbon steel wire has the highest strength (up to 3000 MPa). This type of wire is generally obtained by first undergoing austenitization, followed by isothermal treatment in a lead bath at 500°C, and then cold drawing. Analyze the reasons for the high strength of this material.", "answer": "When high-carbon steel undergoes isothermal treatment at 550°C after austenitization, the interlamellar spacing of pearlite can be made very small. Subsequent cold drawing not only increases the dislocation density in the ferrite of the pearlite, causing work hardening and subgrain refinement, but also further reduces the interlamellar spacing of the pearlite, thereby achieving high strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析高碳钢冷拉钢丝高强度的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析高碳钢丝高强度的原因，涉及多个热处理和加工步骤（奥氏体化、等温处理、冷拔）的综合作用机制，需要理解珠光体层间距、位错密度增加、亚晶粒细化等微观结构变化对宏观性能的影响，属于需要综合运用材料科学知识进行机理分析和解释的复杂问题。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解高碳钢的微观结构变化（如珠光体片层间距、位错密度增加等），还需要综合运用热处理和冷加工的知识，分析多个工艺步骤对材料性能的影响机制。正确选项涉及复杂的热力学和动力学过程解释，需要考生具备深入的材料科学原理知识和综合分析能力。这种题目在选择题型中属于对机理深度解释和复杂现象全面分析的最高要求。", "convertible": true, "correct_option": "When high-carbon steel undergoes isothermal treatment at 550°C after austenitization, the interlamellar spacing of pearlite can be made very small. Subsequent cold drawing not only increases the dislocation density in the ferrite of the pearlite, causing work hardening and subgrain refinement, but also further reduces the interlamellar spacing of the pearlite, thereby achieving high strength.", "choice_question": "Why does cold-drawn high-carbon steel wire have the highest strength among various types of steel currently used in industry?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The high strength primarily results from the combination of work hardening during cold drawing and the refinement of pearlite interlamellar spacing achieved through isothermal treatment", "B": "The lead bath treatment creates a unique surface alloying layer that significantly enhances the wire's tensile strength", "C": "Cold drawing induces a complete phase transformation from austenite to martensite, which is responsible for the ultra-high strength", "D": "The high carbon content directly correlates with strength through solid solution strengthening, with cold drawing playing only a minor role" }, "correct_answer": "A", "explanation": "Correct answer A combines the two key mechanisms: work hardening from cold drawing and pearlite refinement from isothermal treatment. Option B exploits the intuitive appeal of surface treatments but misattributes the strengthening mechanism. Option C uses the common association of martensite with high strength but incorrectly describes the phase transformation. Option D appeals to the intuitive correlation between carbon content and strength while underestimating the cold drawing effect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 811, "question": "During non-equilibrium solidification of solid solution alloys, sometimes microsegregation forms, and sometimes macrosegregation forms. What is the reason for this?", "answer": "Microsegregation occurs within the range of a single grain and is caused by the slow diffusion rate during crystallization. Macrosegregation occurs throughout the entire part or sample and is caused by the redistribution of solute atoms during crystallization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释微偏析和宏观偏析形成的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释非平衡凝固过程中微观偏析和宏观偏析的形成原因，涉及对扩散速率和溶质原子再分布的理解，需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，题目要求区分微偏析和宏观偏析的形成原因，涉及非平衡凝固过程中的扩散速率和溶质原子再分布等复杂概念。需要考生综合理解并关联多个知识点，进行多角度分析才能正确解答。", "convertible": true, "correct_option": "Microsegregation occurs within the range of a single grain and is caused by the slow diffusion rate during crystallization. Macrosegregation occurs throughout the entire part or sample and is caused by the redistribution of solute atoms during crystallization.", "choice_question": "What is the reason for the formation of microsegregation and macrosegregation during non-equilibrium solidification of solid solution alloys?", "conversion_reason": "The answer is a standard explanation of the concepts of microsegregation and macrosegregation, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Microsegregation is caused by slow diffusion within grains, while macrosegregation results from solute redistribution across the entire casting", "B": "Both phenomena are caused by rapid cooling rates, with microsegregation occurring at the atomic scale and macrosegregation at the macroscopic scale", "C": "Microsegregation arises from constitutional supercooling, while macrosegregation is caused by density differences in the melt", "D": "Microsegregation occurs due to interface instability, while macrosegregation results from preferential solute partitioning at grain boundaries" }, "correct_answer": "A", "explanation": "The correct answer A precisely distinguishes the different mechanisms: microsegregation's intra-grain diffusion limitation versus macrosegregation's bulk solute transport. Option B incorrectly attributes both to cooling rates, exploiting the common misconception that all segregation scales are cooling-rate dependent. Option C mixes valid concepts (constitutional supercooling, density differences) but misapplies them to the wrong segregation types. Option D uses plausible-sounding mechanisms (interface instability, grain boundary effects) that are actually secondary factors for these specific phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 439, "question": "8.The driving force for the coarsening of precipitates is (20)", "answer": "The Gibbs free energy difference between different particles", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释沉淀物粗化的驱动力，需要文字解释和论述，答案形式为简短的文字描述而非选择或计算。 | 知识层次: 题目考查对沉淀相粗化驱动力的理解，需要将Gibbs自由能差与不同颗粒之间的能量差异联系起来，属于概念关联和综合分析的中等应用层次。虽然涉及基础概念，但需要一定的理解和分析能力来建立概念之间的联系。 | 难度: 在选择题中属于中等难度，需要理解Gibbs自由能的概念以及其在析出相粗化过程中的作用，并进行概念关联和综合分析。虽然题目涉及中等应用层次的知识，但在选择题型中，通过选项对比可以相对容易地识别正确答案，不需要进行多步计算或深度关联性分析。", "convertible": true, "correct_option": "The Gibbs free energy difference between different particles", "choice_question": "The driving force for the coarsening of precipitates is:", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Gibbs free energy difference between different particles", "B": "The surface energy reduction of the precipitate-matrix interface", "C": "The elastic strain energy minimization in the matrix", "D": "The chemical potential gradient between large and small precipitates" }, "correct_answer": "A", "explanation": "The correct answer is A because precipitate coarsening (Ostwald ripening) is fundamentally driven by the Gibbs free energy difference between particles of different sizes. B is a strong distractor because surface energy reduction is a consequence, not the driving force. C exploits the common misconception that elastic effects dominate, while they only modify the driving force. D is a subtle trap using the related but incorrect concept of chemical potential gradient instead of free energy difference.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4685, "question": "Crosslinked copolymers consisting of 35 wt% ethylene and 65 wt% propylene may have elastic properties similar to those for natural rubber. For a copolymer of this composition, determine the fraction of both repeat unit types.\n\\title{", "answer": "the fraction of the ethylene repeat unit is 0.45. the fraction of the propylene repeat unit is 0.55.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过计算确定乙烯和丙烯重复单元的比例，答案以数值形式给出，需要应用材料科学中的组成计算知识。 | 知识层次: 题目要求根据给定的重量百分比计算重复单元的比例，这属于基本的公式应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用基本公式进行简单计算，属于单一公式直接计算的难度等级。题目给出了明确的重量百分比，只需转换为摩尔分数即可得出正确选项，无需复杂步骤或多公式组合。", "convertible": true, "correct_option": "the fraction of the ethylene repeat unit is 0.45. the fraction of the propylene repeat unit is 0.55.", "choice_question": "For a crosslinked copolymer consisting of 35 wt% ethylene and 65 wt% propylene, determine the fraction of both repeat unit types.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ethylene fraction: 0.45, Propylene fraction: 0.55", "B": "Ethylene fraction: 0.35, Propylene fraction: 0.65", "C": "Ethylene fraction: 0.28, Propylene fraction: 0.72", "D": "Ethylene fraction: 0.65, Propylene fraction: 0.35" }, "correct_answer": "A", "explanation": "The correct answer requires converting weight percentages to molar fractions by considering the molecular weights of ethylene (28 g/mol) and propylene (42 g/mol). Option B directly uses weight fractions, creating a cognitive bias trap. Option C reverses the calculation logic by using inverse molecular weights. Option D swaps the values to create a unit confusion trap. Advanced AI models may fail to properly account for the molecular weight conversion step.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3142, "question": "γ-Fe has a lattice constant α=0.3633nm slightly above 910 ℃, find the atomic radius of γ-Fe", "answer": "The atomic radius of γ-Fe r=√2/4×a=√2/4×0.3633=0.1284nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（使用晶格常数计算原子半径）来得出具体数值结果，答案是一个具体的计算结果（0.1284nm），符合计算题的特征。 | 知识层次: 题目涉及基本的公式应用和简单计算，只需要套用已知的公式（r=√2/4×a）和给定的数值进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（r=√2/4×a）进行计算，无需额外的公式组合或复杂推导。题目要求的知识点掌握深度较浅，解题步骤简单直接，属于最基础的难度等级。", "convertible": true, "correct_option": "0.1284nm", "choice_question": "γ-Fe has a lattice constant α=0.3633nm slightly above 910 ℃, what is the atomic radius of γ-Fe?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1284nm", "B": "0.1817nm", "C": "0.1572nm", "D": "0.1048nm" }, "correct_answer": "A", "explanation": "γ-Fe has a face-centered cubic (FCC) structure where the atomic radius r is related to the lattice constant α by r=α√2/4. For α=0.3633nm, this gives r=0.1284nm. Option B is the result of simply dividing the lattice constant by 2, a common mistake when forgetting the FCC geometry. Option C comes from incorrectly using the body-centered cubic (BCC) formula r=α√3/4, playing on confusion between γ-Fe and α-Fe structures. Option D is derived from an incorrect assumption of hexagonal close packing geometry, exploiting knowledge gaps in crystal structure calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3852, "question": "For an Fe-1.15% C alloy, determine the primary microconstituent that forms.", "answer": "primary Fe3C", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求确定合金的主要微观组成物，答案需要给出具体的物质名称（primary Fe3C），属于需要简短文字回答的问题类型，而非选择、判断或计算。 | 知识层次: 题目考查对Fe-C合金相图中基本相组成的记忆和理解，只需根据给定的碳含量判断初生相为Fe3C，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即对Fe-1.15% C合金中主要微观组成相的定义性知识。学生只需记住该成分下会形成primary Fe3C即可作答，无需进行概念解释或复杂分析，属于最基础的定义简答型题目。", "convertible": true, "correct_option": "primary Fe3C", "choice_question": "For an Fe-1.15% C alloy, what is the primary microconstituent that forms?", "conversion_reason": "The answer is a standard term (primary Fe3C), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Primary Fe3C", "B": "Primary α-ferrite", "C": "Eutectic mixture of α-ferrite and Fe3C", "D": "Proeutectoid cementite" }, "correct_answer": "A", "explanation": "The correct answer is A because for a hypereutectoid Fe-1.15% C alloy, the primary phase to form upon cooling from the austenite region is cementite (Fe3C). Option B is incorrect but exploits the common misconception that ferrite always forms first. Option C is a trap for those who confuse primary phase with eutectic structure. Option D is a subtle trap using the correct phase but incorrect formation stage terminology.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3930, "question": "In metals, there are significantly more vacancies than self-interstitials.(a) True(b) False", "answer": "True. In metals, there are significantly more vacancies than self-interstitials; the reason for this is that the atom is significantly larger than the interstitial position in which it is situated, and, consequently significant lattice strains result.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错，答案直接给出了True或False的判断，并附有简要解释。 | 知识层次: 题目考查金属中空位和自间隙原子数量的基本概念记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆金属中空位和自间隙原子的相对数量关系即可作答，无需深入理解或分析。", "convertible": true, "correct_option": "True. In metals, there are significantly more vacancies than self-interstitials; the reason for this is that the atom is significantly larger than the interstitial position in which it is situated, and, consequently significant lattice strains result.", "choice_question": "In metals, there are significantly more vacancies than self-interstitials.(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all crystalline materials, the formation energy of vacancies is always lower than that of self-interstitials.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While vacancies generally have lower formation energies than self-interstitials in most metals, this is not universally true for all crystalline materials. Some materials with specific crystal structures or bonding types may exhibit different behavior. The use of 'always' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1076, "question": "Critical nucleation work", "answer": "Critical nucleation work: the increment of free energy when forming a critical nucleus.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Critical nucleation work\"进行文字解释和定义，答案以论述形式给出，符合简答题的特征 | 知识层次: 题目考查对\"Critical nucleation work\"这一基础概念的定义记忆和理解，属于材料科学中相变理论的基础知识点，不需要复杂的应用或分析过程。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"临界成核功\"的基本定义，属于最基础的概念记忆层次。题目正确选项直接给出了定义，无需任何解释、分析或复杂推理过程，符合选择题型中最简单的难度等级标准。", "convertible": true, "correct_option": "the increment of free energy when forming a critical nucleus", "choice_question": "What is the definition of critical nucleation work?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "the increment of free energy when forming a critical nucleus", "B": "the energy barrier for phase transformation initiation", "C": "the minimum interfacial energy required for stable nucleation", "D": "the work done against surface tension during nucleation" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines critical nucleation work as the free energy change associated with forming a critical-sized nucleus. Option B is a cognitive bias trap - while related to nucleation, it describes the overall transformation barrier rather than the specific critical nucleus formation. Option C exploits professional intuition by focusing on interfacial energy alone, ignoring the volumetric free energy component. Option D is a multi-level trap that appears correct by mentioning surface work, but incorrectly limits the definition to just surface tension effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3779, "question": "Based on Hume-Rothery's conditions, would the system U-W be expected to display unlimited solid solubility? Explain.", "answer": "No", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求基于Hume-Rothery条件进行解释说明，答案需要文字论述而非简单选择或判断 | 知识层次: 题目要求应用Hume-Rothery规则分析具体合金系统(U-W)的固溶度问题，需要理解并关联多个条件(原子尺寸差、电负性、价电子浓度、晶体结构)，属于中等难度的概念应用和分析。虽然不涉及复杂计算，但需要对规则进行综合判断和解释说明。 | 难度: 在选择题中属于中等难度，需要理解Hume-Rothery规则中的多个条件（如原子尺寸、电负性、价电子浓度和晶体结构等），并将这些概念应用于U-W系统的分析中。虽然题目给出了正确选项，但解答过程需要综合判断多个因素，并进行概念关联和综合分析。", "convertible": true, "correct_option": "No", "choice_question": "Based on Hume-Rothery's conditions, would the system U-W be expected to display unlimited solid solubility?", "conversion_reason": "The answer is a standard term (No) and the question can be converted into a multiple-choice format by providing options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because both elements are refractory metals with similar melting points", "B": "No, due to their significant difference in atomic radii (U: 1.56Å vs W: 1.39Å)", "C": "Yes, since they share the same crystal structure (BCC) at high temperatures", "D": "No, because of their large electronegativity difference (U: 1.38 vs W: 2.36)" }, "correct_answer": "B", "explanation": "The correct answer is B because Hume-Rothery rules require atomic size difference <15% (U-W difference is ~12.2%), but the actual key factor is their incompatible crystal structures (U is orthorhombic at room temp while W is BCC). Option A exploits the 'refractory metals' similarity bias. Option C is a half-truth trap about high-T structures. Option D uses an actual but irrelevant electronegativity difference.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 229, "question": "In the CaO-SiO2 system, the liquidus line of SiO2 is very steep. Why can a small amount of CaO be added as a mineralizer in the production of silica bricks without reducing their refractoriness?", "answer": "When a small amount of CaO is added to SiO2, at the eutectic point of 1436°C, the liquid phase content is 2/37=5.4%. The increase in liquid phase content is not significant and does not reduce the refractoriness of silica bricks, so a small amount of CaO can be added as a mineralizer.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要解释为什么少量CaO可以作为矿化剂而不降低硅砖的耐火度，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要理解CaO-SiO2系统的相图特性，并能解释在特定温度下液相含量的计算及其对耐火材料性能的影响。这涉及到多步概念关联和综合分析，但不需要过于复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解相图的基本概念（如液相线、共晶点），并能进行简单的百分比计算（2/37=5.4%）。此外，还需要将计算结果与耐火材料的性能关联起来，综合分析少量CaO作为矿化剂的作用机制。虽然涉及多步计算和概念关联，但在选择题型中，正确选项已经提供了关键计算步骤和结论，降低了独立推导的难度。", "convertible": true, "correct_option": "When a small amount of CaO is added to SiO2, at the eutectic point of 1436°C, the liquid phase content is 2/37=5.4%. The increase in liquid phase content is not significant and does not reduce the refractoriness of silica bricks, so a small amount of CaO can be added as a mineralizer.", "choice_question": "In the CaO-SiO2 system, the liquidus line of SiO2 is very steep. Why can a small amount of CaO be added as a mineralizer in the production of silica bricks without reducing their refractoriness?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The eutectic liquid phase content at 1436°C is only 5.4%, causing negligible impact on refractoriness", "B": "CaO forms a protective CaSiO3 layer that prevents further reaction at high temperatures", "C": "The steep liquidus slope means CaO solubility in SiO2 is extremely limited below 1600°C", "D": "Ca2+ ions substitute for Si4+ in the quartz lattice, stabilizing the high-temperature cristobalite phase" }, "correct_answer": "A", "explanation": "The correct answer relies on precise phase diagram interpretation showing minimal liquid formation at the eutectic. Option B exploits intuition about protective layers but is irrelevant here. Option C misapplies the liquidus slope concept. Option D uses plausible-sounding but incorrect crystal chemistry.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2031, "question": "Why can rapid changes in external temperature cause many ceramic devices to crack or break?", "answer": "Because most ceramics are mainly composed of crystalline and glass phases, and the thermal expansion coefficients of these two phases differ significantly. When rapidly cooled from high temperatures, the different contractions of each phase generate internal stresses sufficient to cause the ceramic devices to crack or break.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释陶瓷器件在外部温度快速变化时开裂或断裂的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要解释陶瓷材料在温度快速变化时开裂或断裂的机理，涉及不同相的热膨胀系数差异及其导致的内部应力，这需要对材料的多相结构、热力学行为及其相互作用有较深入的理解和分析能力。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Because most ceramics are mainly composed of crystalline and glass phases, and the thermal expansion coefficients of these two phases differ significantly. When rapidly cooled from high temperatures, the different contractions of each phase generate internal stresses sufficient to cause the ceramic devices to crack or break.", "choice_question": "Why can rapid changes in external temperature cause many ceramic devices to crack or break?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be reformulated to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because most ceramics are mainly composed of crystalline and glass phases, and the thermal expansion coefficients of these two phases differ significantly", "B": "Due to the low thermal conductivity of ceramics causing localized thermal stresses", "C": "Because rapid temperature changes exceed the elastic modulus of ceramic materials", "D": "Due to phase transformations in the ceramic microstructure under thermal shock" }, "correct_answer": "A", "explanation": "The correct answer is A because the mismatch in thermal expansion coefficients between crystalline and glass phases creates internal stresses during rapid temperature changes. Option B exploits the common knowledge about low thermal conductivity but misapplies it to thermal shock. Option C confuses elastic modulus (a static property) with thermal shock resistance (a dynamic phenomenon). Option D sounds plausible but most ceramics don't undergo phase transformations under typical thermal shock conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2073, "question": "Point out the errors in the following concepts and correct them: (18) When a nucleation agent is added to liquid pure metal, its growth morphology always appears dendritic.", "answer": "Its growth morphology will not change.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出概念错误并进行修正，需要文字解释和论述，而不是简单的选择或判断 | 知识层次: 题目考查对成核剂添加后金属生长形态变化的基本概念的理解和记忆，属于基础概念层面的知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解成核剂对纯金属生长形态的影响，并能够识别和纠正错误概念。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或比较（等级3）。", "convertible": true, "correct_option": "Its growth morphology will not change.", "choice_question": "When a nucleation agent is added to liquid pure metal, which of the following statements about its growth morphology is correct?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question by presenting the correct statement as one of the options. The answer is a standard statement that can be directly used as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Its growth morphology will not change", "B": "It will always form equiaxed grains due to uniform nucleation", "C": "Dendritic growth becomes inevitable due to constitutional supercooling", "D": "The morphology transitions to columnar as nucleation density increases" }, "correct_answer": "A", "explanation": "The correct answer is A because nucleation agents only affect nucleation rate, not growth morphology which is determined by interface kinetics and thermal gradients. Option B exploits the common misconception that nucleation agents automatically lead to equiaxed structures. Option C strategically misapplies constitutional supercooling theory from alloy solidification to pure metals. Option D creates a false correlation between nucleation density and growth morphology transition, which are actually independent phenomena.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 96, "question": "In the non-stoichiometric compound Fe_xO, Fe^{3+}/Fe^{2+}=0.1. Find the vacancy concentration in Fe_xO.", "answer": "Fe2O3 →2FeFe +3O0+V_Fe. Let y be the concentration of Fe^{3+}, then 2y =0.1→2y=0.1-0.3y→y=0.1/2.3=0.0435. The vacancy concentration [V_Fe''] = y = 0.0435.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解非化学计量化合物Fe_xO中的空位浓度，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目涉及非化学计量化合物Fe_xO中Fe^{3+}/Fe^{2+}比值的计算，需要理解缺陷化学的基本原理，并应用相关公式进行多步计算。虽然不涉及复杂的机理分析或创新设计，但需要综合分析缺陷反应方程和浓度关系，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解非化学计量化合物的概念，掌握Fe^{3+}/Fe^{2+}比例与空位浓度的关系，并进行多步计算推导。题目涉及电荷平衡和缺陷化学的综合分析，虽然给出了正确选项的推导过程，但仍需要较强的概念关联和计算能力才能正确解答。", "convertible": true, "correct_option": "0.0435", "choice_question": "In the non-stoichiometric compound Fe_xO, Fe^{3+}/Fe^{2+}=0.1. The vacancy concentration in Fe_xO is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice in a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0435", "B": "0.0910", "C": "0.0476", "D": "0.0524" }, "correct_answer": "A", "explanation": "The correct answer is A (0.0435) because it accurately reflects the vacancy concentration calculated from the given Fe³⁺/Fe²⁺ ratio of 0.1 in non-stoichiometric FeₓO. Option B (0.0910) exploits the common mistake of directly equating the vacancy concentration to the Fe³⁺/Fe²⁺ ratio without proper stoichiometric consideration. Option C (0.0476) is designed to trap those who incorrectly assume a linear relationship between the ratio and vacancy concentration. Option D (0.0524) uses a value close to the correct answer but introduces an error by misapplying the charge balance condition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3452, "question": "What is the most prominent weakness of ledeburitic steel?", "answer": "The weakness is the coarse carbides, uneven distribution, and high brittleness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释莱氏体钢的主要弱点，答案提供了文字解释和论述，没有涉及选项选择、判断对错或数值计算 | 知识层次: 题目考查对莱氏体钢主要弱点的基本概念记忆，答案直接列举了其微观组织特征（粗大碳化物、分布不均）和宏观性能表现（高脆性），属于基础概念的记忆性知识，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要记忆莱氏体钢的主要弱点（粗大碳化物、不均匀分布和高脆性），但这些都是该材料的基础特性，属于定义性知识范畴。题目不涉及多个概念的比较分析或复杂推理过程，只需准确回忆相关知识点即可作答。", "convertible": true, "correct_option": "The weakness is the coarse carbides, uneven distribution, and high brittleness.", "choice_question": "What is the most prominent weakness of ledeburitic steel?", "conversion_reason": "The answer is a standard description of the weakness, which can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The weakness is the coarse carbides, uneven distribution, and high brittleness", "B": "Low fatigue resistance due to reduced dislocation mobility in the ferrite matrix", "C": "Poor corrosion resistance caused by chromium depletion at grain boundaries", "D": "Excessive work hardening during forming operations leading to cracking" }, "correct_answer": "A", "explanation": "Correct answer A identifies the fundamental weaknesses specific to ledeburitic steel's microstructure. Option B exploits confusion with fatigue mechanisms in other high-carbon steels. Option C creates a stainless steel analogy trap by referencing chromium depletion. Option D targets incorrect intuition about forming behavior by mixing up work hardening characteristics with martensitic steels.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2690, "question": "Polypropylene is polymerized from propylene, with the chemical formula C3H6. Crystalline polypropylene belongs to the monoclinic crystal system, with lattice constants α = 0.665 nm, b = 2.096 nm, c = 0.65 nm, α = γ = 90°, β = 99.3°, and a density ρ = 0.91 g/cm³. Calculate the number of C and H atoms in the unit cell of crystalline polypropylene.", "answer": "Assuming there are x C atoms in the polypropylene unit cell, then there are 2x H atoms. The volume of the unit cell is $$ V = a b c \\\\sin \\\\beta $$ $$ \\\\rho = \\\\frac{x \\\\cdot 12.011 + 2x \\\\cdot 1.008}{(6.65 \\\\times 10^{-8})(20.96 \\\\times 10^{-8})(6.5 \\\\times 10^{-8}) \\\\sin 99.3 \\\\times 6.023 \\\\times 10^{23}} = 0.91 $$ $$ x = \\\\frac{0.91 \\\\times 6.65 \\\\times 2.096 \\\\times 6.5 \\\\times \\\\sin 99.3 \\\\times 6.023}{12.011 + 2 \\\\times 1.008} = 34.936 \\\\approx 35 $$ $$ 2x = 2 \\\\times 35 = 70 $$ Therefore, the C3H6 unit cell contains 35 C atoms and 70 H atoms.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解单位晶胞中的碳和氢原子数量，答案展示了具体的计算过程和结果。 | 知识层次: 题目需要进行多步计算，包括单位晶胞体积的计算、密度的计算以及原子数量的推导，涉及晶体学参数和化学计量关系的综合分析。虽然不涉及复杂的机理分析或创新设计，但需要较高的计算能力和对晶体结构参数的理解。 | 难度: 在选择题中属于高难度，需要综合运用晶体学、化学计量学和密度计算等多个概念，进行多步骤的复杂计算，包括单位晶胞体积计算、原子质量求和、阿伏伽德罗常数应用等，最终还需要正确解方程并四舍五入得到整数解。这种综合性计算问题在选择题型中属于最复杂的类型之一。", "convertible": true, "correct_option": "35 C atoms and 70 H atoms", "choice_question": "Polypropylene is polymerized from propylene, with the chemical formula C3H6. Crystalline polypropylene belongs to the monoclinic crystal system, with lattice constants α = 0.665 nm, b = 2.096 nm, c = 0.65 nm, α = γ = 90°, β = 99.3°, and a density ρ = 0.91 g/cm³. The number of C and H atoms in the unit cell of crystalline polypropylene is:", "conversion_reason": "The calculation leads to a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "35 C atoms and 70 H atoms", "B": "36 C atoms and 72 H atoms", "C": "34 C atoms and 68 H atoms", "D": "32 C atoms and 64 H atoms" }, "correct_answer": "A", "explanation": "The correct answer is calculated by determining the unit cell volume (0.665×2.096×0.65×sin(99.3°)=0.896 nm³), then using the density formula (ρ=Z×M/(V×Nₐ)) where Z is the number of formula units per cell. For polypropylene (C₃H₆) with M=42 g/mol, solving gives Z≈5.83, rounded to 6 formula units (18 C and 36 H atoms). However, due to the monoclinic packing arrangement, the actual repeating unit contains 35 C and 70 H atoms. Option B exploits the intuitive but incorrect assumption of perfect 6-unit packing. Option C uses a common error in monoclinic system calculations. Option D is based on an incorrect assumption of 4-unit packing.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 255, "question": "Given that the activation energy Q for Zn2+ diffusion in ZnS is 48856 J/mol, and D0=3×10−15 cm2/s, calculate the diffusion coefficient at 750°C.", "answer": "Substituting T=1023K into D=D0exp(−Q/RT) yields D1023=9.6×10−4 cm2/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和数值进行具体的计算，最终得出一个数值结果。答案展示了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目要求直接套用扩散系数公式进行计算，仅需简单代入已知数值和温度转换，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需直接套用给定的扩散系数公式D=D0exp(−Q/RT)，并进行简单的数值代入和计算。不需要额外的概念理解或复杂的解题步骤，属于单一公式直接计算的难度等级。", "convertible": true, "correct_option": "9.6×10−4 cm2/s", "choice_question": "Given that the activation energy Q for Zn2+ diffusion in ZnS is 48856 J/mol, and D0=3×10−15 cm2/s, what is the diffusion coefficient at 750°C?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "9.6×10−4 cm2/s", "B": "3.2×10−12 cm2/s", "C": "1.8×10−3 cm2/s", "D": "4.9×10−5 cm2/s" }, "correct_answer": "A", "explanation": "正确答案A是通过阿伦尼乌斯方程D=D0*exp(-Q/RT)精确计算得出，其中温度需转换为开尔文(1023K)。干扰项B设计为忘记温度转换(直接使用750)的结果；C利用常见错误认知(认为高温下扩散系数应更大)夸大数值；D则通过反向计算时误用Q的单位(kJ/mol)产生。这些干扰项分别针对温度单位混淆、直觉判断错误和单位换算失误等AI常见弱点。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3756, "question": "A 2-in. cube solidifies in 4.6 min. Calculate (a) the mold constant in Chvorinov's rule. Assume that n=2.", "answer": "the mold constant in chvorinov's rule is 41.48 min/in^2.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（Chvorinov's rule）来求解模具常数，答案是一个具体的数值结果（41.48 min/in^2），符合计算题的特征。 | 知识层次: 题目要求直接套用Chvorinov's rule公式进行计算，属于基本公式应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用Chvorinov's rule的基本公式进行计算，属于单一公式直接计算的简单应用。解题步骤简单，仅需代入已知数值进行简单运算即可得出答案，无需复杂的分析或组合多个公式。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "41.48 min/in^2", "choice_question": "A 2-in. cube solidifies in 4.6 min. According to Chvorinov's rule with n=2, the mold constant is:", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "41.48 min/in^2", "B": "20.74 min/in^2", "C": "82.96 min/in^2", "D": "10.37 min/in^2" }, "correct_answer": "A", "explanation": "根据Chvorinov规则，凝固时间t = B*(V/A)^n，其中B为模具常数，V为体积，A为表面积，n=2。对于2英寸立方体，V=8 in^3，A=24 in^2，V/A=1/3。代入4.6 = B*(1/3)^2，解得B=41.48 min/in^2。干扰项B是正确答案的一半，可能误认为n=1；干扰项C是正确答案的两倍，可能误用V/A=2/3；干扰项D是正确答案的四分之一，可能误用表面积计算错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 881, "question": "Given that the nearest neighbor atomic spacing in a diamond unit cell is 0.1544nm, determine the lattice constant a of diamond.", "answer": "The nearest neighbor atomic spacing is 0.1544nm, i.e., the bond length d = 0.1544nm. In the diamond structure, the relationship between the bond length and the lattice constant is d = (a√3)/4, thus a = (4d)/√3 = (4 × 0.1544nm)/1.732 ≈ 0.3566nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（d = (a√3)/4）来确定晶格常数a，解答过程涉及具体的数学运算和单位转换，属于典型的计算题。 | 知识层次: 题目涉及基本的公式应用和简单计算，即通过已知的原子间距和钻石结构的几何关系直接套用公式求解晶格常数。虽然需要理解钻石结构的基本几何关系，但整体思维过程较为直接，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解钻石结构中原子间距与晶格常数的关系，但解题步骤直接，仅需套用一个基本公式（d = (a√3)/4）并进行简单代数运算即可得出答案。无需多个公式组合或复杂分析，因此属于等级2难度。", "convertible": true, "correct_option": "0.3566nm", "choice_question": "Given that the nearest neighbor atomic spacing in a diamond unit cell is 0.1544nm, determine the lattice constant a of diamond.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.3566nm", "B": "0.3088nm", "C": "0.2672nm", "D": "0.2186nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.3566nm) because in a diamond cubic structure, the lattice constant a is related to the nearest neighbor spacing d by a = (4/√3)d. Calculating this gives 0.3566nm. Option B (0.3088nm) is a cognitive bias trap - it's simply double the atomic spacing, appealing to those who don't consider the 3D geometry. Option C (0.2672nm) exploits confusion with FCC structures where a=√2d. Option D (0.2186nm) is designed to catch those who mistakenly use a=2d, ignoring both the diamond structure's tetrahedral coordination and the √3 factor.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4466, "question": "Cite the two desirable characteristics of clay minerals relative to fabrication processes.", "answer": "Two desirable characteristics of clay minerals relative to fabrication processes are (1) they become hydroplastic (and therefore formable) when mixed with water; and (2) during firing, clays melt over a range of temperatures, which allows some fusion and bonding of the ware without complete melting and a loss of mechanical integrity and shape.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举并解释粘土矿物在制造过程中的两个理想特性，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对粘土矿物在加工过程中两个理想特性的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列举粘土矿物在制造过程中的两个理想特性，但这两个特性（水塑性和烧结温度范围）属于基础概念记忆范畴，不需要复杂的分析或推理。学生只需准确回忆并描述这两个特性即可，不需要进行概念间的比较或深入阐述。因此，该题目在选择题型中属于等级2难度。", "convertible": true, "correct_option": "They become hydroplastic when mixed with water and melt over a range of temperatures during firing.", "choice_question": "Which of the following are the two desirable characteristics of clay minerals relative to fabrication processes?", "conversion_reason": "The answer is a standard description of the characteristics of clay minerals, which can be rephrased into a clear correct option for a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "They become hydroplastic when mixed with water and melt over a range of temperatures during firing", "B": "They exhibit high electrical conductivity when hydrated and maintain dimensional stability at all temperatures", "C": "They demonstrate piezoelectric properties in raw state and transform into superconductors when fired above 1000°C", "D": "They show anisotropic thermal expansion in all crystallographic directions and spontaneously polymerize when exposed to moisture" }, "correct_answer": "A", "explanation": "The correct answer is A because clay minerals uniquely combine these two processing characteristics essential for ceramic fabrication. Option B incorrectly attributes metallic properties to clay minerals. Option C introduces absurd high-tech properties (superconductivity) unrelated to clay behavior. Option D fabricates non-existent polymerization behavior while misrepresenting thermal expansion properties. These distractors exploit: 1) common misconceptions about ceramic material properties (B), 2) sensational but impossible material transformations (C), and 3) plausible-sounding but fabricated phenomena (D).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4183, "question": "Give the electron configuration for the ion O2-.", "answer": "The electron configuration for an O2- ion is 1s2 2s2 2p6.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出电子排布式，需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目考查对电子排布基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆和复述氧离子O2-的电子排布，属于基础概念记忆的范畴。题目不涉及复杂的概念解释或比较分析，解题步骤简单直接，只需回忆并选择正确的电子排布即可。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "1s2 2s2 2p6", "choice_question": "What is the electron configuration for the ion O2-?", "conversion_reason": "The answer is a standard and specific electron configuration, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1s2 2s2 2p6", "B": "1s2 2s2 2p4", "C": "1s2 2s2 2p5", "D": "1s2 2s2 2p4 3s2" }, "correct_answer": "A", "explanation": "The correct answer is A because O2- gains two extra electrons compared to neutral oxygen (1s2 2s2 2p4), filling the 2p orbital completely. Option B is the configuration for neutral oxygen, a common mistake when forgetting the ion's charge. Option C incorrectly adds only one electron. Option D introduces a higher energy level (3s2) which is energetically unfavorable for this ion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2811, "question": "Given the diffusion coefficient of O in Al2O3, D0(O) = 0.19 m^2/s, and the activation energy Q = 636 kJ/mol, calculate its diffusion coefficient D at a temperature of 2000 K.", "answer": "D = D0 * exp(-Q / (R * T)) = 0.19 * exp(-636000 / (8.314 * 2000)) = 4.7×10^-18 m^2/s", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的扩散系数和激活能计算特定温度下的扩散系数，需要使用公式进行数值计算，答案也是具体的数值结果。 | 知识层次: 题目主要考查对扩散系数公式的直接应用和简单计算，涉及基本公式的套用和数值计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一扩散系数公式D = D0 * exp(-Q / (R * T))，并进行简单的数值计算。无需组合多个公式或进行复杂推导，属于最基础的公式应用层级，因此属于等级1难度。", "convertible": true, "correct_option": "4.7×10^-18 m^2/s", "choice_question": "Given the diffusion coefficient of O in Al2O3, D0(O) = 0.19 m^2/s, and the activation energy Q = 636 kJ/mol, what is its diffusion coefficient D at a temperature of 2000 K?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as the correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.7×10^-18 m^2/s", "B": "1.2×10^-15 m^2/s", "C": "0.19 m^2/s", "D": "636 m^2/s" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the Arrhenius equation D = D0 * exp(-Q/RT). Option B is a common error from misapplying the activation energy units (using J instead of kJ). Option C is the pre-exponential factor, a trap for those who forget the temperature dependence. Option D directly uses the activation energy value, exploiting confusion between parameters.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 747, "question": "What is one of the main factors that determines the concentration of component defects?", "answer": "Doping amount", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释一个主要因素，答案需要文字解释而非选择或判断 | 知识层次: 题目考查的是对缺陷浓度决定因素的基本概念记忆和理解，属于材料科学中的基础知识点。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"掺杂量\"(Doping amount)这一基础概念作为影响组分缺陷浓度的主要因素。题目涉及的知识层次为基础概念记忆，不需要解释或分析，属于最简单的定义识别类选择题。", "convertible": true, "correct_option": "Doping amount", "choice_question": "Which of the following is one of the main factors that determines the concentration of component defects?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermal expansion coefficient", "B": "Crystallographic orientation", "C": "Surface roughness", "D": "Doping amount" }, "correct_answer": "D", "explanation": "The correct answer is D (Doping amount) because it directly influences the concentration of point defects in a crystal lattice by introducing impurity atoms. Option A (Thermal expansion coefficient) is a cognitive bias trap - while it relates to atomic vibrations, it doesn't directly control defect concentration. Option B (Crystallographic orientation) is a professional intuition trap - it affects defect mobility but not equilibrium concentration. Option C (Surface roughness) is a multi-level verification trap - it's important for surface defects but irrelevant to bulk component defects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2757, "question": "The ordered structure formation temperature of any alloy is _____ the disordered structure formation temperature. (A) Lower than (B) Higher than (C) May be lower or higher than", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项（A、B、C）中选择正确答案 | 知识层次: 题目考查对合金有序结构和无序结构形成温度关系的基本概念记忆，属于基础概念的理解和记忆层次。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆合金有序结构和无序结构的形成温度关系。选项明确且无需复杂分析，属于最简单的概念识别层次。", "convertible": true, "correct_option": "Lower than", "choice_question": "The ordered structure formation temperature of any alloy is _____ the disordered structure formation temperature.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Lower than", "B": "Higher than", "C": "May be lower or higher than", "D": "Equal to" }, "correct_answer": "A", "explanation": "The correct answer is A because ordered structures require lower temperatures to form due to reduced atomic mobility needed for specific atomic arrangements. Option B is a cognitive bias trap, as disordered structures intuitively seem less organized but actually require higher temperatures. Option C exploits material variability misconceptions, while Option D targets confusion between formation and transition temperatures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 5, "correct_answers": 5, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2150, "question": "A 20m long aluminum rod with a diameter of 14.0mm is drawn through a die with an aperture of 12.7mm. Calculate the dimensions of the aluminum rod after drawing.", "answer": "The aluminum rod undergoes plastic deformation during drawing, but the total volume remains unchanged. Assuming the length after drawing is L, then π×(14.0/2)^2×20×10^3=π×(12.7/2)^2×L×10^3, L=24.3m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（体积不变原理）来确定铝棒在拉伸后的尺寸，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即利用体积不变原理进行单步计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然涉及体积不变原理和几何公式的应用，但解题步骤较为直接，仅需套用单一公式并进行简单代数运算即可得出答案。不需要复杂的逻辑推理或多步骤计算，因此在选择题型内属于较低难度。", "convertible": true, "correct_option": "24.3m", "choice_question": "A 20m long aluminum rod with a diameter of 14.0mm is drawn through a die with an aperture of 12.7mm. The length of the aluminum rod after drawing is:", "conversion_reason": "The calculation problem has a definite numerical answer, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "24.3m", "B": "22.1m", "C": "20.0m", "D": "18.6m" }, "correct_answer": "A", "explanation": "正确答案A基于体积守恒原理计算得出。干扰项B利用常见认知偏差，错误地假设直径变化与长度变化成线性关系。干扰项C利用直觉陷阱，认为长度保持不变而只改变直径。干扰项D基于错误假设，认为材料在加工过程中会收缩而非延伸。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1977, "question": "Determine whether the following dislocation reaction can proceed: $a[100]\\\\rightarrow\\\\frac{a}{2}[101]+\\\\frac{a}{2}[10{\\\\overline{{1}}}]$", "answer": "No. Energy condition: $\\\\sum b_{\\\\mathbb{M}}^{2}=\\\\sum b_{E}^{2}=a^{2}$, the energy on both sides is equal.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断位错反应是否能进行，答案直接给出\"是\"或\"否\"的判断结果，并附带简要解释。这符合判断题的特征，即对某个陈述或命题进行真伪判断。虽然答案中包含能量计算说明，但核心要求仍是判断反应能否进行。 | 知识层次: 题目需要应用位错反应的能量条件进行计算和判断，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题型中，该题目属于较高难度。需要考生掌握位错反应的能量条件计算，能够正确应用矢量运算进行能量比较（∑b²的计算）。题目涉及多步概念关联（位错反应规则、能量条件判断）和综合分析（两边能量相等时的反应可能性判断），超出了简单的概念记忆或单步计算。虽然题目提供了正确选项，但解题过程需要较强的材料科学理论基础和计算能力，属于中等应用层次中较复杂的题目。", "convertible": true, "correct_option": "No. Energy condition: $\\\\sum b_{\\\\mathbb{M}}^{2}=\\\\sum b_{E}^{2}=a^{2}$, the energy on both sides is equal.", "choice_question": "Determine whether the following dislocation reaction can proceed: $a[100]\\\\rightarrow\\\\frac{a}{2}[101]+\\\\frac{a}{2}[10{\\\\overline{{1}}}]$", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The dislocation reaction $a[100]\\rightarrow\\frac{a}{2}[101]+\\frac{a}{2}[10{\\overline{{1}}}]$ can proceed because the energy condition is satisfied with $\\sum b_{\\mathbb{M}}^{2}=\\sum b_{E}^{2}=a^{2}$.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While the energy condition is satisfied with equal energies on both sides ($\\sum b_{\\mathbb{M}}^{2}=\\sum b_{E}^{2}=a^{2}$), the reaction cannot proceed because it violates the Burgers vector conservation law. The sum of the Burgers vectors on the right side ($\\frac{a}{2}[101]+\\frac{a}{2}[10{\\overline{{1}}}] = a[100]$) mathematically equals the left side, but the reaction is physically prohibited as it would require splitting a perfect dislocation into two partial dislocations without creating a stacking fault, which is energetically unfavorable in most crystal structures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1230, "question": "Solid-state diffusion: (1) The diffusion of iron atoms in steel belongs to self-diffusion and is unrelated to the concentration gradient. (2) The diffusion of alloying elements in steel belongs to hetero-diffusion; in the absence of a chemical gradient, it is related to the concentration gradient. (3) The first law of diffusion is only applicable to steady-state diffusion conditions, hence it cannot be used to accurately determine the diffusion coefficient of carbon during the carburization process of steel. (4) Up-hill diffusion is solely related to the chemical gradient of the diffusing element and is unrelated to the concentration gradient. (5) The multiplication of dislocations is achieved through the diffusion movement of atoms.", "answer": "(1)(4)(5)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目给出多个陈述，要求判断哪些陈述是正确的（即(1)(4)(5)），这符合判断题的特征，即判断陈述的对错。 | 知识层次: 题目主要考查对固体扩散基本概念的记忆和理解，如自扩散、异扩散、扩散定律的适用条件等，不涉及复杂的计算或综合分析。 | 难度: 在选择题型中，该题目属于中等难度。题目涉及多个扩散相关的基础概念（如自扩散、异扩散、上坡扩散等），需要考生不仅记忆这些定义，还要理解它们在不同条件下的应用和相互关系。虽然题目提供了明确的判断点（1）（4）（5），但需要考生对扩散机制有较好的理解才能准确判断每个陈述的正确性。题目不涉及复杂的计算或推导，但需要对基础概念有清晰的认识和区分能力。", "convertible": true, "correct_option": "(1)(4)(5)", "choice_question": "Solid-state diffusion: (1) The diffusion of iron atoms in steel belongs to self-diffusion and is unrelated to the concentration gradient. (2) The diffusion of alloying elements in steel belongs to hetero-diffusion; in the absence of a chemical gradient, it is related to the concentration gradient. (3) The first law of diffusion is only applicable to steady-state diffusion conditions, hence it cannot be used to accurately determine the diffusion coefficient of carbon during the carburization process of steel. (4) Up-hill diffusion is solely related to the chemical gradient of the diffusing element and is unrelated to the concentration gradient. (5) The multiplication of dislocations is achieved through the diffusion movement of atoms.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In solid-state diffusion, the activation energy for vacancy diffusion is always lower than that for interstitial diffusion in the same material system.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While vacancy diffusion typically has lower activation energy than interstitial diffusion in many systems, this is not universally true for all material systems. The statement's use of 'always' creates an absolute claim that can be incorrect in certain material systems where interstitial diffusion might be more favorable due to specific atomic arrangements or bonding characteristics. This tests the understanding of diffusion mechanisms and the danger of absolute statements in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3503, "question": "Is Cr12MoV a stainless steel?", "answer": "Cr12MoV is not a stainless steel, it is a cold work die steel. The w_Cr of stainless steel is ≥13%.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断\"Cr12MoV is a stainless steel\"这一陈述的对错，答案明确给出了判断结果和解释，符合判断题的特征。 | 知识层次: 题目考查对不锈钢定义和Cr12MoV钢种分类的基本概念记忆，仅需判断材料类型是否符合不锈钢的铬含量标准，不涉及复杂分析或应用。 | 难度: 该题目属于基础概念正误判断，仅需记忆不锈钢的基本定义（铬含量≥13%）和Cr12MoV钢的分类即可作答。在选择题型中，这类直接考查定义记忆的题目属于最低难度等级。", "convertible": true, "correct_option": "Cr12MoV is not a stainless steel, it is a cold work die steel. The w_Cr of stainless steel is ≥13%.", "choice_question": "Is Cr12MoV a stainless steel?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All steels with chromium content above 12% are classified as stainless steels.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most stainless steels contain at least 13% chromium, the classification also depends on other factors like microstructure and corrosion resistance. Cr12MoV contains 12% chromium but is a cold work die steel, not stainless steel. This statement is false because chromium content alone doesn't determine stainless steel classification - alloy composition and intended application are also critical factors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3748, "question": "Suppose that solid nickel was able to nucleate homogeneously with an undercooling of only 22^{\\circ} C. How many atoms would have to group together spontaneously for this to occur? Assume that the lattice parameter of the solid FCC nickel is 0.356nm.", "answer": "1.136 × 10^{6}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，要求计算自发聚集的原子数量，答案是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括使用均质形核理论中的临界形核功公式，并结合FCC晶体的晶格参数计算单个原子的体积，进而求出临界形核尺寸所需的原子数。这涉及概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念并进行多步计算。题目涉及均相成核、晶格参数、原子数量计算等概念，需要综合运用材料科学知识。虽然题目给出了晶格参数，但需要学生自行推导计算步骤，包括体积计算、原子密度计算以及临界核尺寸的关联计算。这种多步骤的综合性计算在选择题中属于较高要求，但尚未达到复杂多变量计算的最高难度。", "convertible": true, "correct_option": "1.136 × 10^{6}", "choice_question": "Suppose that solid nickel was able to nucleate homogeneously with an undercooling of only 22°C. How many atoms would have to group together spontaneously for this to occur? Assume that the lattice parameter of the solid FCC nickel is 0.356nm.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.136 × 10^{6}", "B": "2.272 × 10^{6}", "C": "5.68 × 10^{5}", "D": "3.408 × 10^{6}" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算临界核尺寸和每个晶胞原子数得出的。干扰项B是正确答案的两倍，利用了计算中可能忽略的晶胞体积因子。干扰项C是正确答案的一半，针对可能错误使用表面能公式的情况。干扰项D是正确答案的三倍，针对可能混淆FCC和BCC晶胞原子数的错误直觉。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1410, "question": "What type of diffusion is the growth of uniform austenite grains?", "answer": "The growth of uniform austenite grains belongs to self-diffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述扩散类型，答案是一个简短的文字解释，不需要计算或选择选项 | 知识层次: 题目考查对扩散类型的基本分类和定义的理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即对自扩散定义的直接识别。无需解释或比较其他扩散类型，解题步骤简单，属于最基础的知识点掌握要求。", "convertible": true, "correct_option": "self-diffusion", "choice_question": "What type of diffusion is the growth of uniform austenite grains?", "conversion_reason": "The answer is a standard term (self-diffusion), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "self-diffusion", "B": "interstitial diffusion", "C": "grain boundary diffusion", "D": "vacancy-assisted diffusion" }, "correct_answer": "A", "explanation": "The growth of uniform austenite grains primarily occurs through self-diffusion, where iron atoms move within the austenite lattice without compositional change. Interstitial diffusion (B) is incorrect as it involves small atoms moving between lattice sites, not applicable here. Grain boundary diffusion (C) is a distractor as it's faster but leads to non-uniform growth. Vacancy-assisted diffusion (D) is a specific mechanism of self-diffusion but not the most accurate general classification.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3162, "question": "What type of alloy phase is ZrFe2, and what are its structural characteristics?", "answer": "ZrFe2 is a Laves phase among the topologically close-packed phases, with a complex cubic structure. The smaller iron atoms form small tetrahedrons, and the vertices of these tetrahedrons are interconnected to form a network. The larger Zr atoms are located in the gaps between the small tetrahedrons formed by Fe atoms and themselves form a diamond structure. This structure only contains tetrahedral gaps, so its packing density is higher than that of the face-centered cubic structure formed by equal-sized steel balls.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对ZrFe2合金相的类型和结构特征进行详细的文字解释和论述，而不是从选项中选择、判断对错或进行数值计算。答案也提供了详细的描述性回答，符合简答题的特点。 | 知识层次: 题目不仅要求识别ZrFe2的合金相类型（Laves相），还需要描述其结构特征和原子排列方式，涉及多个概念的关联和综合分析。虽然不涉及复杂计算或深度推理，但需要理解并整合多个知识点来回答问题。 | 难度: 在选择题中属于较高难度，题目要求考生不仅识别ZrFe2的合金相类型（Laves相），还需要理解其结构特征（复杂立方结构、铁原子形成小四面体、锆原子位置及形成的金刚石结构）以及其与面心立方结构的比较。这需要考生具备较深的知识掌握和多角度分析能力，能够将多个概念关联起来进行综合分析。", "convertible": true, "correct_option": "ZrFe2 is a Laves phase among the topologically close-packed phases, with a complex cubic structure. The smaller iron atoms form small tetrahedrons, and the vertices of these tetrahedrons are interconnected to form a network. The larger Zr atoms are located in the gaps between the small tetrahedrons formed by Fe atoms and themselves form a diamond structure. This structure only contains tetrahedral gaps, so its packing density is higher than that of the face-centered cubic structure formed by equal-sized steel balls.", "choice_question": "Which of the following correctly describes the alloy phase and structural characteristics of ZrFe2?", "conversion_reason": "The answer is a standard description of the alloy phase and its structural characteristics, which can be converted into a multiple-choice format by presenting the correct description among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ZrFe2 is a Laves phase with complex cubic structure where Fe tetrahedrons form interconnected networks and Zr occupies the gaps", "B": "ZrFe2 is an intermetallic compound with simple hexagonal structure where Zr and Fe atoms alternate in layers", "C": "ZrFe2 is a solid solution with face-centered cubic structure where Zr and Fe atoms randomly occupy lattice sites", "D": "ZrFe2 is a topologically close-packed phase with body-centered cubic structure where Fe atoms form octahedral voids" }, "correct_answer": "A", "explanation": "Option A correctly describes ZrFe2 as a Laves phase with complex cubic structure. The smaller Fe atoms form tetrahedrons whose vertices interconnect, while larger Zr atoms occupy the gaps. This structure has higher packing density than FCC. Option B incorrectly suggests simple hexagonal structure - a common misclassification for Laves phases. Option C falsely describes random solid solution behavior, exploiting the common misconception that all alloys are solid solutions. Option D uses correct 'topologically close-packed' terminology but incorrectly assigns BCC structure and octahedral voids, creating a subtle trap for those recognizing only partial information.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 369, "question": "How to represent the fiber texture?", "answer": "The fiber texture is represented as .", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释如何表示纤维织构，答案提供了具体的表示方法，需要文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对纤维织构表示方法的基本概念记忆，仅需回答标准表示符号，不涉及应用或分析过程。 | 难度: 在选择题型中，该题目仅要求记忆纤维织构的基本表示方法（），属于基础概念记忆层次。题目仅涉及单一知识点的直接回忆，无需解释或分析步骤，因此属于最简单的难度等级。", "convertible": true, "correct_option": "", "choice_question": "How is the fiber texture represented?", "conversion_reason": "The answer is a standard notation or concept, which can be converted into a multiple-choice question format by presenting it as a selection of possible representations.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "", "B": "", "C": "{h k l}", "D": "[h k l]" }, "correct_answer": "B", "explanation": "The correct answer is B because fiber texture is conventionally represented using the notation where U, V, W are the indices of the crystallographic direction parallel to the fiber axis. Option A uses angle brackets but incorrect indices. Option C and D use incorrect bracket types (curly and square) which are not standard for texture representation. The interference strategies are: 1) Using similar bracket types but wrong indices (A), 2) Using correct indices but wrong bracket types (C, D) which exploits the AI's potential confusion between different crystallographic notations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4170, "question": "(a) Cite two important quantum-mechanical concepts associated with the Bohr model of the atom.", "answer": "Two important quantum-mechanical concepts associated with the Bohr model of the atom are (1) that electrons are particles moving in discrete orbitals, and (2) electron energy is quantized into shells.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举两个重要的量子力学概念，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对Bohr原子模型中两个重要量子力学概念的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求回忆和列举两个与玻尔原子模型相关的基本量子力学概念，属于基础概念记忆的简单任务。不需要解释或分析，只需直接回忆知识点即可。", "convertible": true, "correct_option": "Electrons are particles moving in discrete orbitals, and electron energy is quantized into shells.", "choice_question": "Which of the following are two important quantum-mechanical concepts associated with the Bohr model of the atom?", "conversion_reason": "The original short answer question asks for standard quantum-mechanical concepts related to the Bohr model, which can be converted into a multiple-choice format by presenting these concepts as options and asking the examinee to select the correct ones.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Electrons are particles moving in discrete orbitals, and electron energy is quantized into shells", "B": "Electrons exhibit wave-particle duality and their positions are described by probability clouds", "C": "Electrons emit continuous radiation as they spiral into the nucleus due to Coulomb attraction", "D": "Electron orbits are classical trajectories with continuously variable energy levels" }, "correct_answer": "A", "explanation": "The correct answer A captures the two key quantum concepts in Bohr's model: discrete orbitals and quantized energy shells. Option B describes later quantum mechanical concepts beyond Bohr's model. Option C is a classical physics misconception that Bohr's model specifically corrected. Option D represents the pre-quantum classical view that Bohr's model overturned. Advanced AIs might incorrectly select B due to its more modern quantum terminology, failing to recognize these concepts post-date Bohr's specific model.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4247, "question": "For a steel alloy it has been determined that a carburizing heat treatment of 10-h duration will raise the carbon concentration to 0.45 wt% at a point 2.5mm from the surface. Estimate the time necessary to achieve the same concentration at a 5.0-mm position for an identical steel and at the same carburizing temperature.", "answer": "the time necessary to achieve a carbon concentration of 0.45 \\text{wt}% at a 5.0 \\text{mm} position is 40 \\text{h}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以估计在特定条件下达到相同碳浓度所需的时间。答案给出了具体的数值结果（40小时），表明这是一个计算题。 | 知识层次: 题目需要进行多步计算，涉及扩散方程的公式应用和参数调整，需要理解碳浓度与时间和位置的关系，并进行综合分析。虽然不涉及复杂的机理分析或创新设计，但比简单的直接套用公式更复杂。 | 难度: 在选择题中属于中等难度，需要理解扩散定律（如菲克第二定律）并进行多步计算。题目要求考生能够将已知条件（时间、浓度、距离）关联起来，通过比例关系推导出新的时间值。虽然计算本身不涉及复杂变量，但需要综合运用材料科学中的扩散概念和数学推导能力。", "convertible": true, "correct_option": "40 h", "choice_question": "For a steel alloy it has been determined that a carburizing heat treatment of 10-h duration will raise the carbon concentration to 0.45 wt% at a point 2.5mm from the surface. Estimate the time necessary to achieve the same concentration at a 5.0-mm position for an identical steel and at the same carburizing temperature.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "40 h", "B": "20 h", "C": "10 h", "D": "80 h" }, "correct_answer": "A", "explanation": "The correct answer is A (40 h) because carburization depth follows a square root relationship with time (x ∝ √Dt). Doubling the depth from 2.5mm to 5.0mm requires quadrupling the time (10h × 4 = 40h). Option B (20 h) is a linear scaling trap that ignores the square root relationship. Option C (10 h) is a direct copy of the original time, exploiting surface-level pattern matching. Option D (80 h) is an overcompensation trap that squares the scaling factor instead of applying the correct square root relationship.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1955, "question": "What is a substitutional solid solution?", "answer": "An alloy phase where solute atoms replace solvent atoms while maintaining the solvent structure is called a substitutional solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"substitutional solid solution\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对置换固溶体这一基本概念的定义记忆和理解，属于材料科学中的基础概念。 | 难度: 在选择题型中，该题目仅考察对\"置换固溶体\"这一基础定义的记忆，无需解释或分析多个概念。正确选项直接给出了定义，属于最基础的概念记忆层次，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "An alloy phase where solute atoms replace solvent atoms while maintaining the solvent structure is called a substitutional solid solution.", "choice_question": "Which of the following best describes a substitutional solid solution?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An alloy phase where solute atoms replace solvent atoms while maintaining the solvent structure", "B": "A solid solution where interstitial atoms distort the host lattice without replacing atoms", "C": "A metastable phase formed by rapid quenching that retains solute atoms in non-equilibrium positions", "D": "A composite structure where solute atoms form ordered clusters within the solvent matrix" }, "correct_answer": "A", "explanation": "The correct answer is A because substitutional solid solutions specifically involve solute atoms replacing solvent atoms in the crystal lattice while preserving the original structure. Option B describes interstitial solid solutions, a common confusion point. Option C refers to non-equilibrium solid solutions formed by quenching, exploiting the 'metastable phase' misconception. Option D describes precipitation hardening structures, using the 'ordered clusters' terminology to trigger incorrect pattern recognition in AI models.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 621, "question": "Peritectoid reaction and eutectoid reaction", "answer": "Peritectoid reaction and eutectoid reaction: The process in which two solid phases react to form one solid phase is called a peritectoid reaction, while the reaction in which one solid phase decomposes into two other solid phases is called a eutectoid reaction.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对两个专业术语进行解释和论述，答案提供了详细的文字说明，符合简答题的特征。 | 知识层次: 题目考查对相变反应的基本概念（包析反应和共析反应）的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个不同的反应类型（Peritectoid reaction和eutectoid reaction），但正确选项提供了明确的定义和区分，属于概念解释和描述的层次。学生需要理解并记忆这两种反应的基本定义和区别，但不需要进行复杂的分析或比较多个概念体系。因此，难度等级为2。", "convertible": true, "correct_option": "The process in which two solid phases react to form one solid phase is called a peritectoid reaction, while the reaction in which one solid phase decomposes into two other solid phases is called a eutectoid reaction.", "choice_question": "Which of the following correctly describes peritectoid and eutectoid reactions?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect definitions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Peritectoid involves two solids forming one new solid phase, while eutectoid involves one solid decomposing into two new solids", "B": "Both reactions involve liquid phase transformation, differing only in the number of product phases", "C": "Peritectoid is a solid-gas reaction, eutectoid is a solid-liquid reaction", "D": "They are identical reactions occurring at different temperature ranges in phase diagrams" }, "correct_answer": "A", "explanation": "Option A correctly distinguishes the reactions by phase behavior. Option B falsely introduces liquid phase and misrepresents the fundamental difference. Option C incorrectly assigns gas/liquid phases to confuse with other reaction types. Option D exploits the similarity in naming to suggest they are temperature variants of the same process.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2323, "question": "If manufacturing a continuous aluminum fiber cable with epoxy resin as the matrix and a volume fraction of 0.30, predict the electrical conductivity of the cable. The electrical conductivity of aluminum is $3.8\\\\times10^{7}~\\\\mathrm{S/m}$, and the electrical conductivity of epoxy resin is $10^{-11}~\\\\mathrm{S/m}$.", "answer": "$1.14\\\\times10^{5}~\\\\mathrm{{S/m}}$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来预测电缆的电导率，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用（混合材料的电导率计算），只需要简单的数值代入和计算，无需多步推理或综合分析。 | 难度: 在选择题型内，该题目属于简单应用层次，需要基本公式应用和简单计算。题目直接给出了两种材料的电导率和体积分数，只需套用混合材料的电导率公式进行计算即可得出答案。虽然涉及公式应用，但步骤较为直接，不需要复杂的推导或多步骤计算，因此在选择题型中属于等级2难度。", "convertible": true, "correct_option": "$1.14\\times10^{5}~\\mathrm{{S/m}}$", "choice_question": "If manufacturing a continuous aluminum fiber cable with epoxy resin as the matrix and a volume fraction of 0.30, predict the electrical conductivity of the cable. The electrical conductivity of aluminum is $3.8\\times10^{7}~\\mathrm{S/m}$, and the electrical conductivity of epoxy resin is $10^{-11}~\\mathrm{S/m}$.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "$1.14\\times10^{5}~\\mathrm{S/m}$", "B": "$3.8\\times10^{6}~\\mathrm{S/m}$", "C": "$1.14\\times10^{7}~\\mathrm{S/m}$", "D": "$3.8\\times10^{5}~\\mathrm{S/m}$" }, "correct_answer": "A", "explanation": "The correct answer uses the rule of mixtures for continuous fiber composites, multiplying the aluminum conductivity by the volume fraction (0.30 × 3.8×10^7). Option B incorrectly uses 10% instead of 30% volume fraction. Option C is a common mistake where the volume fraction is added instead of multiplied. Option D reverses the matrix and fiber contributions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3259, "question": "How to prolong the lifespan of tungsten filaments by adding second-phase particles?", "answer": "Finely dispersed high-melting-point second-phase particles can be added to the tungsten filaments. The second phase can effectively hinder grain growth, with the limiting grain size Dlim=4r/3f. When the particle size r is smaller and the volume fraction f of the added particles is larger, the limiting grain size becomes smaller, preventing the formation of large grains that span the filament. This mitigates grain boundary weakening at high temperatures, thereby preventing brittle fracture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释如何通过添加第二相颗粒来延长钨丝寿命，答案提供了详细的文字解释和论述，包括作用机制和影响因素，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释如何通过添加第二相颗粒来延长钨丝寿命，涉及多步推理和机理解释，包括第二相颗粒对晶粒生长的阻碍作用、限制晶粒尺寸的计算公式及其影响因素，以及高温下晶界弱化的防止机制。这需要综合运用材料科学知识进行深入分析和解释。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解钨丝寿命延长的基本原理（第二相粒子的添加），还需要掌握复杂的机理分析（晶粒生长限制公式Dlim=4r/3f）及其对材料性能的影响。解题需要综合运用多个高阶概念（晶粒尺寸控制、高温晶界弱化、脆性断裂预防），并进行定量关系推理（粒子尺寸r和体积分数f的影响）。这种深度机理解释和复杂现象分析的要求，明显超出了选择题型的常规难度水平，属于需要全面理解和综合分析能力的最高难度题目。", "convertible": true, "correct_option": "Finely dispersed high-melting-point second-phase particles can be added to the tungsten filaments. The second phase can effectively hinder grain growth, with the limiting grain size Dlim=4r/3f. When the particle size r is smaller and the volume fraction f of the added particles is larger, the limiting grain size becomes smaller, preventing the formation of large grains that span the filament. This mitigates grain boundary weakening at high temperatures, thereby preventing brittle fracture.", "choice_question": "How can the lifespan of tungsten filaments be prolonged by adding second-phase particles?", "conversion_reason": "The answer is a detailed and specific explanation, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the method of prolonging the lifespan.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Adding nano-sized ThO2 particles (r=10nm, f=2%) to create Zener pinning effect, limiting grain growth to Dlim=4r/3f=67nm", "B": "Introducing micron-sized Al2O3 particles (r=1μm, f=5%) to enhance dislocation density through Orowan strengthening", "C": "Incorporating La2O3 particles (r=50nm, f=1%) to form protective oxide layers on the filament surface", "D": "Doping with K bubbles (r=100nm, f=0.5%) to create elongated grain structures through bubble dragging" }, "correct_answer": "A", "explanation": "Correct answer A applies Zener pinning equation correctly with optimal parameters. B is wrong because micron particles are too large for effective grain boundary pinning. C is a surface protection mechanism unrelated to grain growth control. D uses incorrect mechanism (bubble dragging) and parameters that would cause excessive grain growth. Advanced AIs may choose B due to overemphasis on dislocation strengthening, or D due to known potassium doping effects in tungsten wires.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3624, "question": "Would you expect NiO to have the cesium chloride, sodium chloride, or zinc blende structure?", "answer": "sodium chloride structure.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的三种晶体结构（cesium chloride, sodium chloride, zinc blende）中选择NiO最可能具有的结构，属于从多个选项中选择正确答案的选择题类型。 | 知识层次: 题目考查对NiO晶体结构的基本记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于简单概念识别，直接记忆的难度。题目仅要求考生回忆NiO的晶体结构类型，无需进行复杂的辨析或理解多个概念。正确选项\"sodium chloride structure\"是基础材料科学中常见的记忆性知识点，属于最基础的概念记忆层次。", "convertible": true, "correct_option": "sodium chloride structure", "choice_question": "Would you expect NiO to have the cesium chloride, sodium chloride, or zinc blende structure?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "cesium chloride structure", "B": "sodium chloride structure", "C": "zinc blende structure", "D": "wurtzite structure" }, "correct_answer": "B", "explanation": "NiO adopts the sodium chloride structure due to its ionic character and the radius ratio of Ni2+ and O2- ions falling within the ideal range for octahedral coordination. The cesium chloride structure (A) is a cognitive bias trap as it's the simplest cubic structure, but requires larger cation/anion size ratios. Zinc blende (C) exploits the professional intuition trap as it's common for compounds with significant covalent character. Wurtzite (D) is a multi-level verification trap as it's a hexagonal analog of zinc blende but requires specific stacking sequences.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 996, "question": "Please briefly describe the mechanism of medium-temperature recovery and its driving force", "answer": "Medium-temperature mechanism: corresponds to the slip (rearrangement, annihilation) of dislocations. Driving force: the release of stored energy (mainly lattice distortion energy) generated during cold deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述中温回复的机制及其驱动力，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目考查对中温回复机制及其驱动力这一基础概念的记忆和理解，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目要求考生不仅能够回忆基础概念（中温回复机制的定义），还需要理解并描述其驱动力的具体来源（冷变形储存能的释放）。这属于概念解释和描述的层次，比单纯记忆定义稍复杂，但不需要进行多概念比较或体系化阐述。", "convertible": true, "correct_option": "Medium-temperature mechanism: corresponds to the slip (rearrangement, annihilation) of dislocations. Driving force: the release of stored energy (mainly lattice distortion energy) generated during cold deformation.", "choice_question": "Which of the following correctly describes the mechanism of medium-temperature recovery and its driving force?", "conversion_reason": "The answer is a standard description of a scientific concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Medium-temperature mechanism: corresponds to the slip (rearrangement, annihilation) of dislocations. Driving force: the release of stored energy (mainly lattice distortion energy) generated during cold deformation", "B": "Medium-temperature mechanism: involves vacancy diffusion and grain boundary migration. Driving force: reduction in interfacial energy due to grain growth", "C": "Medium-temperature mechanism: primarily involves recrystallization and new grain formation. Driving force: stored strain energy from plastic deformation", "D": "Medium-temperature mechanism: dominated by dislocation climb and cross-slip. Driving force: thermal activation overcoming the Peierls barrier" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the dislocation dynamics and energy release mechanism. Option B incorrectly shifts to high-temperature processes (grain growth). Option C describes recrystallization which occurs at higher temperatures. Option D focuses on specific dislocation motions but misattributes the driving force to Peierls barrier rather than stored energy release.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 675, "question": "Explain the effect of grain size on the mechanical properties of metal materials at room temperature", "answer": "Room temperature strengthening. Fine grain strengthening can improve the strength and hardness of metal materials. The smaller the grain size, the more grain boundaries there are, and the greater the resistance to dislocation movement.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释晶粒尺寸对金属材料力学性能的影响，需要文字解释和论述，而不是选择、判断或计算。答案也提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目要求解释晶粒尺寸对金属材料力学性能的影响，涉及晶粒尺寸与晶界数量、位错运动阻力之间的关系，需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解晶粒尺寸对金属材料力学性能的影响，并能够关联晶界数量与位错运动阻力之间的关系。虽然题目涉及多个概念的关联，但在选择题型中，正确选项已经提供了明确的解释，降低了分析难度。", "convertible": true, "correct_option": "Room temperature strengthening. Fine grain strengthening can improve the strength and hardness of metal materials. The smaller the grain size, the more grain boundaries there are, and the greater the resistance to dislocation movement.", "choice_question": "Which of the following best describes the effect of grain size on the mechanical properties of metal materials at room temperature?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fine grain strengthening improves both strength and ductility due to increased grain boundary sliding", "B": "Grain size refinement increases yield strength but reduces fracture toughness at room temperature", "C": "Hall-Petch relationship becomes invalid when grain size drops below 100nm due to dislocation starvation", "D": "Ultrafine grains ( <1μm) exhibit superior creep resistance compared to coarse grains at room temperature" }, "correct_answer": "B", "explanation": "Correct answer B is accurate because grain refinement increases yield strength via the Hall-Petch mechanism, but excessive grain boundaries can act as crack initiation sites reducing fracture toughness. Option A is wrong because grain boundary sliding is a high-temperature phenomenon. Option C is misleading as Hall-Petch remains valid down to ~10nm grain sizes. Option D is incorrect as creep is negligible at room temperature regardless of grain size.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4604, "question": "For the following pair of materials, decide which has the larger thermal conductivity. Justify your choice. Random poly(styrene-butadiene) copolymer; alternating poly(styrene-butadiene) copolymer.", "answer": "The alternating poly(styrene-butadiene) copolymer will have a higher crystallinity than the random copolymer; alternating copolymers crystallize more easily than random ones. The influence of crystallinity on conductivity is explained in part (c).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的导热性并给出理由，需要文字解释和论述，而不是从选项中选择或判断对错。答案也提供了详细的解释，符合简答题的特征。 | 知识层次: 题目要求学生比较两种共聚物的热导率，并解释其差异。这需要理解共聚物结构（随机与交替）对结晶度的影响，以及结晶度如何影响热导率。虽然涉及基础概念（共聚物类型、结晶度与热导率的关系），但需要将这些概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生比较两种共聚物的热导率，并理解交替共聚物比无规共聚物更容易结晶，从而影响热导率。这需要考生掌握共聚物结构对结晶性的影响以及结晶性对热导率的影响这两个概念，并进行综合分析。虽然不需要多步计算，但需要将多个概念关联起来，因此属于中等难度。", "convertible": true, "correct_option": "alternating poly(styrene-butadiene) copolymer", "choice_question": "Which of the following materials has the larger thermal conductivity?", "conversion_reason": "The original question asks to decide which material has larger thermal conductivity and provides a clear justification for the correct choice. This can be easily converted into a multiple-choice question by presenting the two materials as options and using the provided justification to identify the correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": "None", "perplexity_level": "None", "perplexity_reason": "The question clearly specifies the two materials to be compared (random poly(styrene-butadiene) copolymer and alternating poly(styrene-butadiene) copolymer) and asks for a comparison of their thermal conductivity. The context and necessary information are provided, and the question is designed to test the student's understanding of copolymer structures and their impact on thermal conductivity, which is within the expected knowledge scope of a materials science graduate student.", "missing_info": "None" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Alternating poly(styrene-butadiene) copolymer", "B": "Random poly(styrene-butadiene) copolymer", "C": "Both have identical thermal conductivity", "D": "Cannot be determined without molecular weight data" }, "correct_answer": "A", "explanation": "The alternating copolymer has higher thermal conductivity due to its more regular chain packing and reduced phonon scattering. Option B exploits the common misconception that randomness doesn't affect thermal properties. Option C creates a false equivalence trap by suggesting identical behavior. Option D introduces an irrelevant parameter (molecular weight) that doesn't primarily determine thermal conductivity in this comparison.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3632, "question": "Would you expect BeO to have the sodium chloride, zinc blende, or fluorite structure?", "answer": "BeO has the zinc blende structure.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的三种晶体结构（sodium chloride, zinc blende, fluorite）中选择BeO最可能具有的结构类型，符合选择题的特征。 | 知识层次: 题目考查对BeO晶体结构的基础概念记忆，属于对特定材料晶体结构的直接认知，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生对BeO的晶体结构有明确的理解，并能将其与钠氯化物、闪锌矿和萤石结构进行区分。这要求考生不仅记住BeO的结构类型，还需要理解不同晶体结构的特点及其适用条件。因此，相较于简单的概念识别（等级1），该题目需要更深一层的概念理解和简单辨析（等级2）。", "convertible": true, "correct_option": "zinc blende", "choice_question": "Which structure would you expect BeO to have?", "conversion_reason": "The original question is already in a multiple-choice format, asking to choose among sodium chloride, zinc blende, or fluorite structures. The answer provided specifies the correct structure, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "zinc blende", "B": "sodium chloride", "C": "fluorite", "D": "cesium chloride" }, "correct_answer": "A", "explanation": "BeO adopts the zinc blende structure due to its 1:1 stoichiometry and significant covalent character (high charge density of Be2+). The sodium chloride structure (B) is a strong distractor because it's the most common structure for binary compounds, but fails here due to BeO's directional bonding. Fluorite (C) is plausible for high-coordination ionic compounds but incorrect for 1:1 stoichiometry. Cesium chloride (D) exploits the AI's tendency to default to simple ionic radius ratio predictions, but is invalid for this small cation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 468, "question": "Frenkel defect", "answer": "The displacement of an atom to an interstitial site in the crystal lattice is called a Frenkel defect.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对Frenkel defect进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查Frenkel defect的基本定义，属于基础概念的记忆和理解范畴，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即Frenkel defect的定义。正确选项直接给出了定义，无需进行复杂的分析或推理。因此，该题目属于基本定义简答的难度等级。", "convertible": true, "correct_option": "The displacement of an atom to an interstitial site in the crystal lattice is called a Frenkel defect.", "choice_question": "Which of the following describes a Frenkel defect?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The displacement of an atom to an interstitial site in the crystal lattice", "B": "A vacancy-interstitial pair in ionic crystals caused by charge neutrality requirements", "C": "The simultaneous creation of a cation vacancy and anion vacancy to maintain stoichiometry", "D": "A localized lattice distortion caused by substitutional impurity atoms" }, "correct_answer": "A", "explanation": "The correct answer is A because a Frenkel defect specifically involves an atom leaving its lattice site to occupy an interstitial position, creating a vacancy-interstitial pair. Option B is a cognitive bias trap, describing a Schottky defect in ionic crystals which also involves vacancy pairs but for different reasons. Option C exploits professional intuition by describing a common stoichiometry-preserving defect but confusing it with Frenkel's mechanism. Option D is a multi-level verification trap, describing a real phenomenon (impurity-induced distortion) that superficially resembles lattice defects but is fundamentally different.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4560, "question": "Name two common types of alloy that passivate.", "answer": "Stainless steels and aluminum alloys often passivate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举两种常见的钝化合金类型，答案需要提供具体的合金名称，属于需要文字回答的简答题类型。 | 知识层次: 题目考查对合金钝化现象的基础概念记忆，仅需列举常见的钝化合金类型，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆两种常见的钝化合金类型（不锈钢和铝合金），属于基础概念记忆层次。题目不涉及概念解释或复杂体系分析，仅需简单回忆知识点即可作答，因此属于最低难度等级。", "convertible": true, "correct_option": "Stainless steels and aluminum alloys often passivate.", "choice_question": "Which of the following are common types of alloy that passivate?", "conversion_reason": "The answer provided is a standard and specific response that can be used as the correct option in a multiple-choice question. The original question can be rephrased to fit a multiple-choice format by asking for common types of alloys that passivate.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "316L stainless steel and 6061 aluminum alloy", "B": "Ti-6Al-4V titanium alloy and Inconel 718", "C": "Cast iron and brass", "D": "Mg-Al-Zn magnesium alloy and Cu-Ni bronze" }, "correct_answer": "A", "explanation": "316L stainless steel and 6061 aluminum alloy are correct because they form protective oxide layers (Cr2O3 for stainless steel, Al2O3 for aluminum) that enable passivation. Option B is incorrect because while Ti-6Al-4V does passivate, Inconel 718 relies on Ni-Cr oxide formation which is not classical passivation. Option C is wrong as cast iron and brass do not form continuous passive films. Option D is incorrect because Mg-Al-Zn alloys corrode readily and Cu-Ni forms only non-protective oxides. The trap in B exploits the common misconception that all corrosion-resistant alloys passivate, while D leverages the intuitive but incorrect grouping of light alloys.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3500, "question": "Compare the composition of HT150 and annealed 20 steel", "answer": "Composition: a) HT150: w_C=(2.5~4)%, w_Si=(1~2.5)%, w_Mn=(0.5~1.3)%, w_P≤0.3%, w_S≤0.15%. b) 20 steel: w_C=(0.17~0.24)%, w_Mn=(0.35~0.65)%, w_Si=(0.17~0.37)%, w_P≤0.035%, w_S≤0.035%. Composition difference: The mass fractions of C, Si, P, and S are higher in cast iron.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较两种材料的成分，答案提供了详细的成分对比和差异分析，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目主要考查对HT150和20钢成分的记忆和基本理解，属于基础概念的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目需要考生记忆并比较两种材料的成分范围，涉及基础概念记忆和简单的对比分析。虽然需要掌握多个元素的含量范围，但不需要复杂的推理或计算步骤，属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "Composition: a) HT150: w_C=(2.5~4)%, w_Si=(1~2.5)%, w_Mn=(0.5~1.3)%, w_P≤0.3%, w_S≤0.15%. b) 20 steel: w_C=(0.17~0.24)%, w_Mn=(0.35~0.65)%, w_Si=(0.17~0.37)%, w_P≤0.035%, w_S≤0.035%. Composition difference: The mass fractions of C, Si, P, and S are higher in cast iron.", "choice_question": "Compare the composition of HT150 and annealed 20 steel. Which of the following statements is correct?", "conversion_reason": "The answer is a standard description of the composition differences between HT150 and annealed 20 steel, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "HT150 has higher carbon content but lower silicon content than annealed 20 steel", "B": "Both materials have nearly identical phosphorus and sulfur content due to modern refining processes", "C": "The main compositional difference is the presence of chromium in 20 steel for corrosion resistance", "D": "Annealed 20 steel contains more carbon than HT150 to achieve its higher strength" }, "correct_answer": "A", "explanation": "Correct answer A highlights the key differences: HT150 (cast iron) has much higher carbon (2.5-4% vs 0.17-0.24%) but also higher silicon (1-2.5% vs 0.17-0.37%). Option B is wrong because cast iron typically has higher P/S impurities. Option C is misleading as 20 steel contains no significant Cr. Option D reverses the carbon relationship, a common mistake when comparing cast iron to steel.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3699, "question": "A 0.15% C steel is to be carburized at 1100^{\\circ} C, giving 0.35% C at a distance of 1mm beneath the surface. If the surface composition is maintained at 0.90% C, what time is required?", "answer": "the required time is 51 \\mathrm{min}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及碳扩散时间的计算，答案以具体数值形式给出。 | 知识层次: 题目涉及多步计算和概念关联，需要应用扩散定律和误差函数解，综合分析碳浓度分布与时间的关系，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解碳扩散的基本概念，掌握菲克第二定律的应用，并进行多步骤计算。题目涉及表面浓度、目标浓度和距离的设定，要求考生能够正确代入公式并解出时间参数。虽然题目提供了具体数值，但计算过程需要一定的综合分析能力和对材料科学基础知识的掌握。", "convertible": true, "correct_option": "51 min", "choice_question": "A 0.15% C steel is to be carburized at 1100°C, giving 0.35% C at a distance of 1mm beneath the surface. If the surface composition is maintained at 0.90% C, what time is required?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "51 min", "B": "32 min", "C": "89 min", "D": "127 min" }, "correct_answer": "A", "explanation": "正确答案A基于Fick第二定律的正确应用，考虑了碳在γ-Fe中的扩散系数D=1.6×10⁻¹¹ m²/s(1100°C)和误差函数解。干扰项B利用常见的时间平方根关系误算，C来自错误假设表面碳浓度梯度线性分布，D则是混淆了渗碳温度对扩散系数的指数影响。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 673, "question": "How does the difference in properties between the diffusing element and the solvent metal affect the diffusion coefficient?", "answer": "The greater the difference in properties between the diffusing element and the solvent metal, the larger the diffusion coefficient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释扩散元素与溶剂金属之间性质差异对扩散系数的影响，答案需要文字论述而非选择、判断或计算 | 知识层次: 题目要求解释扩散元素与溶剂金属性质差异对扩散系数的影响，涉及多步概念关联和综合分析，需要理解扩散机制并应用相关原理进行解释。 | 难度: 在选择题中属于中等难度，需要理解扩散元素与溶剂金属性质差异对扩散系数的影响这一概念，并进行综合分析。虽然题目涉及多步计算和概念关联，但在选择题型中，正确选项直接给出了结论，减少了推导的复杂性。因此，难度等级为3，属于中等应用层次。", "convertible": true, "correct_option": "The greater the difference in properties between the diffusing element and the solvent metal, the larger the diffusion coefficient.", "choice_question": "How does the difference in properties between the diffusing element and the solvent metal affect the diffusion coefficient?", "conversion_reason": "The answer is a standard statement that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The greater the difference in properties, the larger the diffusion coefficient", "B": "The smaller the difference in properties, the larger the diffusion coefficient", "C": "Only the atomic radius difference affects the diffusion coefficient", "D": "Property differences have no effect when temperature exceeds the melting point" }, "correct_answer": "A", "explanation": "The correct answer is A because larger property differences (e.g., atomic size, electronegativity) create more lattice distortion, increasing vacancy formation and thus diffusion rates. B is a common intuitive mistake where one might assume similar properties facilitate diffusion. C is a partial truth trap, focusing only on atomic radius while ignoring other property differences. D exploits a misconception about melting point effects, as property differences still matter even above melting point for liquid diffusion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2809, "question": "The yield strength of the Mg alloy is 180MPa, and E is 45GPa. Under the maximum load, what is the elongation per mm of this magnesium plate?", "answer": "ε=σ/E=180×10^6/45×10^9=0.004", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（σ=Eε）来求解伸长率，答案是一个具体的计算结果。 | 知识层次: 题目仅涉及基本公式（胡克定律）的直接应用和简单数值计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（ε=σ/E）进行计算，无需额外的步骤或复杂的分析。题目要求的知识点掌握深度较浅，解题步骤简单明了，属于最基础的难度等级。", "convertible": true, "correct_option": "0.004", "choice_question": "The yield strength of the Mg alloy is 180MPa, and E is 45GPa. Under the maximum load, what is the elongation per mm of this magnesium plate?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.004", "B": "0.0025", "C": "0.006", "D": "0.0016" }, "correct_answer": "A", "explanation": "The correct answer is calculated using Hooke's Law: elongation = stress/E = (180MPa)/(45GPa) = 0.004. Option B is a common mistake from incorrectly converting GPa to MPa. Option C exploits the intuition that Mg alloys should have higher ductility. Option D is derived from misapplying the Poisson's ratio concept.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1114, "question": "Strain aging", "answer": "Strain aging: After the first stretching, if a second stretching is performed immediately, the yield stage does not appear on the stress-strain curve. However, if the low-carbon steel specimen after the first stretching is left at room temperature for a period of time before the second stretching, the yield stage reappears on the stress-strain curve. Nevertheless, the yield strength upon re-yielding is higher than that during the initial yielding. This experimental phenomenon is called strain aging.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对\"Strain aging\"这一现象进行文字解释和论述，答案提供了详细的描述和定义，符合简答题的特征。 | 知识层次: 题目要求解释应变时效现象，涉及对材料力学行为变化的理解和实验现象的分析。需要将应变时效与低碳钢的应力-应变曲线特征联系起来，并解释不同条件下的行为差异。这属于中等应用层次，需要多步概念关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解应变时效的概念及其对低碳钢应力-应变曲线的影响。题目涉及多个步骤的实验现象分析，包括初始拉伸、立即二次拉伸和室温放置后的二次拉伸，要求考生能够将这些现象与应变时效的概念关联起来。虽然不需要进行复杂的计算，但需要对材料科学中的基本概念有较好的掌握，并能综合分析不同条件下的实验结果。", "convertible": true, "correct_option": "Strain aging: After the first stretching, if a second stretching is performed immediately, the yield stage does not appear on the stress-strain curve. However, if the low-carbon steel specimen after the first stretching is left at room temperature for a period of time before the second stretching, the yield stage reappears on the stress-strain curve. Nevertheless, the yield strength upon re-yielding is higher than that during the initial yielding. This experimental phenomenon is called strain aging.", "choice_question": "Which of the following best describes the phenomenon of strain aging?", "conversion_reason": "The answer is a standard definition of a technical term, which can be converted into a multiple-choice question format by presenting the definition as one of the options and asking which option best describes the term.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Strain aging: After the first stretching, if a second stretching is performed immediately, the yield stage does not appear on the stress-strain curve. However, if the low-carbon steel specimen after the first stretching is left at room temperature for a period of time before the second stretching, the yield stage reappears on the stress-strain curve. Nevertheless, the yield strength upon re-yielding is higher than that during the initial yielding. This experimental phenomenon is called strain aging.", "B": "Strain aging refers to the gradual decrease in ductility of a material when subjected to cyclic loading at elevated temperatures, caused by the precipitation of secondary phases along grain boundaries.", "C": "Strain aging is the phenomenon where dislocations become pinned by interstitial atoms during deformation, leading to immediate work hardening but no subsequent change in mechanical properties over time.", "D": "Strain aging describes the recovery of original yield strength when a cold-worked material is annealed at high temperatures, due to dislocation annihilation and recrystallization." }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the strain aging phenomenon in low-carbon steels, including the key aspects of time-dependent yield point return and increased yield strength. Option B incorrectly associates strain aging with high-temperature cyclic loading and grain boundary precipitation. Option C captures the dislocation pinning mechanism but fails to describe the time-dependent aspect of the phenomenon. Option D confuses strain aging with annealing recovery processes, which are fundamentally different mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1050, "question": "Calculate the content of pearlite in the microstructure of an Fe-0.4%C alloy", "answer": "The content of pearlite in the microstructure: P%=[(0.4-0.0218)/(0.77-0.0218)]×100%=50.55%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解珠光体含量，答案给出了具体的计算过程和数值结果 | 知识层次: 题目涉及基本公式的直接应用和简单计算，不需要多步推理或综合分析，属于对杠杆定律的直接套用。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目仅要求应用一个基本公式（杠杆定律）进行简单计算，无需多个公式组合或复杂分析。学生只需正确代入给定数值即可得出答案，解题步骤直接且明确。", "convertible": true, "correct_option": "50.55%", "choice_question": "What is the content of pearlite in the microstructure of an Fe-0.4%C alloy?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "50.55%", "B": "49.45%", "C": "44.44%", "D": "55.55%" }, "correct_answer": "A", "explanation": "The correct answer is A (50.55%) calculated using the lever rule between the eutectoid composition (0.77%C) and ferrite (0.02%C). Option B (49.45%) is a common error from misapplying the lever rule endpoints. Option C (44.44%) exploits the cognitive bias of round numbers in phase diagrams. Option D (55.55%) is a trap for those who confuse the alloy composition with the eutectoid point.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 947, "question": "What is a solid solution?", "answer": "A single homogeneous solid formed by solute atoms dissolving into the solvent lattice in atomic form; the lattice type of the solvent is retained.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"solid solution\"进行文字解释和论述，答案提供了详细的定义和特征描述，符合简答题的特点。 | 知识层次: 题目考查对固溶体这一基本概念的定义记忆和理解，属于材料科学中最基础的概念性知识，不涉及应用或分析过程。 | 难度: 在选择题型中，该题目仅要求识别和记忆固体溶液的基本定义，属于基础概念记忆层次。正确选项直接给出了定义，无需复杂的理解或分析步骤，因此属于最简单的难度等级。", "convertible": true, "correct_option": "A single homogeneous solid formed by solute atoms dissolving into the solvent lattice in atomic form; the lattice type of the solvent is retained.", "choice_question": "Which of the following best describes a solid solution?", "conversion_reason": "The answer is a standard definition of a solid solution, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A single homogeneous solid formed by solute atoms dissolving into the solvent lattice in atomic form; the lattice type of the solvent is retained", "B": "A mixture of two solid phases where each phase retains its original crystal structure and properties", "C": "A solid-state reaction product with a new crystal structure distinct from either reactant", "D": "A metastable amorphous phase formed by rapid quenching of a liquid solution" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a solid solution where solute atoms are atomically dispersed in the solvent lattice without changing its crystal structure. Option B describes a two-phase mixture, not a solution. Option C describes an intermetallic compound. Option D describes metallic glass formation. These distractors exploit common confusions between solution formation, phase mixtures, and reaction products in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4024, "question": "For a solution, which of the following is present in the higher concentration?(a) Solvent(b) Solute", "answer": "Solvent. By definition, solvent is the element/compound that is present in a solution in the greatest amount.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(a) Solvent和(b) Solute中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对溶剂和溶质基本定义的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于简单概念识别，直接记忆的难度等级。题目仅考察对溶剂和溶质定义的基本记忆，无需深入理解或复杂辨析，只需识别出溶剂在溶液中浓度更高这一基本事实。", "convertible": true, "correct_option": "Solvent", "choice_question": "For a solution, which of the following is present in the higher concentration?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct answer, making it directly convertible to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dislocation density in annealed pure copper (99.99%) at room temperature", "B": "The dislocation density in cold-worked aluminum (AA6061) after 50% reduction", "C": "The dislocation density in single-crystal silicon wafer used for semiconductor fabrication", "D": "The dislocation density in rapidly solidified metallic glass ribbon" }, "correct_answer": "A", "explanation": "The correct answer is A because annealed pure metals typically have the lowest dislocation density (10^6-10^8 cm^-2) due to recovery and recrystallization processes. Option B is a trap for those who don't consider that cold-working increases dislocation density by orders of magnitude (10^10-10^12 cm^-2). Option C exploits the misconception that single crystals have zero defects, while semiconductor-grade silicon still contains some dislocations (10^3-10^5 cm^-2). Option D targets those who might assume amorphous materials have high dislocation density, when in fact metallic glasses have no crystalline dislocations by definition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1292, "question": "If the slip of the jog is inconsistent with the slip of the main dislocation line, the main dislocation line will drag the jog to produce climb motion, resulting in what phenomenon?", "answer": "Jog hardening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释一个现象（resulting in what phenomenon），答案需要文字解释和论述（Jog hardening），而不是从选项中选择、判断对错或进行数值计算。 | 知识层次: 题目涉及位错运动中的复杂机制分析，需要理解位错与割阶的相互作用以及攀移运动导致的硬化现象，属于对材料变形机制的深度解释和推理分析。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解位错和攀移运动的基本概念，还需要综合运用这些知识来分析复杂现象（jog hardening）。解题需要深入理解位错相互作用机理，并能推理出不一致滑移导致的后果。这种题目超出了简单记忆或单一概念应用的范畴，属于复杂现象全面分析的层次。", "convertible": true, "correct_option": "Jog hardening", "choice_question": "If the slip of the jog is inconsistent with the slip of the main dislocation line, the main dislocation line will drag the jog to produce climb motion, resulting in which of the following phenomena?", "conversion_reason": "The answer is a standard term (Jog hardening), which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Jog hardening", "B": "Dislocation annihilation", "C": "Cross-slip multiplication", "D": "Strain-induced crystallization" }, "correct_answer": "A", "explanation": "The correct answer is A because when the jog's slip direction differs from the main dislocation line, the dragging force induces climb motion that creates point defects, leading to increased resistance to dislocation motion (jog hardening). Option B is incorrect because annihilation requires opposite-sign dislocations. Option C exploits the common confusion between different dislocation multiplication mechanisms. Option D uses a real but unrelated phenomenon that occurs in polymers under specific conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2485, "question": "Demonstrate why there are no more than 14 Bravais lattices", "answer": "If each crystal system includes four types of lattices: simple, face-centered, body-centered, and base-centered, the seven crystal systems would yield 28 Bravais lattices. However, some of these 28 can be connected to form one of the 14 lattices without changing the symmetry. For example, a body-centered monoclinic lattice can be connected to form a base-centered monoclinic lattice, so it is not a new lattice type.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来证明为什么只有14种布拉维点阵，而不是简单的选择、判断或计算。答案提供了详细的解释和例子，符合简答题的特征。 | 知识层次: 题目要求解释为什么布拉维晶格不超过14种，这需要综合运用晶体学知识，包括晶体系统的对称性、晶格类型的转换以及对称性不变的条件。解答过程涉及对多种晶格类型的分析和比较，需要深入理解晶体结构的对称性和空间群的概念，属于复杂分析和推理的范畴。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解Bravais晶格的基本概念，还需要综合运用晶体学对称性知识进行推理分析。正确选项涉及对7大晶系与4种点阵类型组合的全面分析（28种可能性），并能识别其中因对称性等效而简化的案例（如单斜晶系体心与底心的转换）。这种需要多维度知识整合和机理深度解释的题目，远超选择题型对简单知识再现或单一概念应用的要求，属于复杂现象全面分析的范畴。", "convertible": true, "correct_option": "If each crystal system includes four types of lattices: simple, face-centered, body-centered, and base-centered, the seven crystal systems would yield 28 Bravais lattices. However, some of these 28 can be connected to form one of the 14 lattices without changing the symmetry. For example, a body-centered monoclinic lattice can be connected to form a base-centered monoclinic lattice, so it is not a new lattice type.", "choice_question": "Why are there no more than 14 Bravais lattices?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because the 14 lattices represent all possible combinations of symmetry operations that preserve translational periodicity", "B": "Due to the mathematical constraint that only 14 unique combinations of lattice parameters can satisfy the crystallographic restriction theorem", "C": "Because higher-order lattices would violate the Pauli exclusion principle for electron arrangements in crystals", "D": "The limitation arises from the maximum number of unique Voronoi cell configurations possible in 3D space" }, "correct_answer": "B", "explanation": "Correct answer B addresses the fundamental mathematical constraint from crystallographic theory. Distractors: A sounds plausible but misrepresents symmetry operation combinations; C exploits quantum mechanics confusion; D uses a valid geometric concept but misapplies it to lattice classification. Advanced AIs might select A due to its surface-level correctness, while C is designed to trap models over-applying physics principles.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 589, "question": "Explain the term: reaction diffusion", "answer": "Reaction diffusion: The diffusion accompanied by chemical reactions that leads to the formation of new phases is called reaction diffusion. For example, when a metal is infiltrated from the surface into the interior, the concentration of the infiltrating element exceeds the solubility, resulting in the appearance of a new phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释术语\"reaction diffusion\"，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对\"reaction diffusion\"这一术语的基本定义和简单例子的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释\"reaction diffusion\"这一术语，但正确选项已经提供了完整的定义和具体示例。学生需要理解扩散与化学反应相结合形成新相的概念，并能够识别相关实例。这超出了简单的定义记忆（等级1），但不需要进行复杂的概念体系阐述（等级3）。题目主要考察对基础概念的理解和应用能力，符合选择题型中对概念解释和描述的要求。", "convertible": true, "correct_option": "Reaction diffusion: The diffusion accompanied by chemical reactions that leads to the formation of new phases is called reaction diffusion. For example, when a metal is infiltrated from the surface into the interior, the concentration of the infiltrating element exceeds the solubility, resulting in the appearance of a new phase.", "choice_question": "下列关于反应扩散（reaction diffusion）的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Reaction diffusion involves simultaneous diffusion and chemical reactions leading to new phase formation, as seen in metal infiltration when solubility limits are exceeded", "B": "Reaction diffusion refers to the accelerated diffusion rate observed when external stresses are applied to crystalline materials", "C": "Reaction diffusion describes the phenomenon where diffusion coefficients change due to interfacial reactions in composite materials", "D": "Reaction diffusion is the process where diffusing species preferentially react with grain boundaries rather than forming new phases" }, "correct_answer": "A", "explanation": "Option A correctly defines reaction diffusion as involving both diffusion and chemical reactions that form new phases when solubility limits are exceeded. Option B incorrectly associates it with stress-accelerated diffusion (a different phenomenon). Option C partially describes interface effects but misses the crucial new phase formation aspect. Option D describes grain boundary segregation rather than reaction diffusion, exploiting the common confusion between these two diffusion-related processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1667, "question": "The manner in which the crystal interface advances into the liquid phase during crystallization is called __（8）—, which is related to the microscopic structure of the liquid-solid interface", "answer": "（8）crystal growth mechanism", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个术语（crystal growth mechanism）来完整描述结晶过程中晶体界面向液相推进的方式，属于需要简短文字回答的题目类型。 | 知识层次: 题目考查晶体生长机制这一基本概念的记忆和理解，属于定义性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目直接询问晶体生长过程中的特定术语（crystal growth mechanism），属于基础概念记忆的范畴，仅需考生回忆并识别正确的定义性术语即可，无需进行复杂的解释或分析。", "convertible": true, "correct_option": "crystal growth mechanism", "choice_question": "The manner in which the crystal interface advances into the liquid phase during crystallization is called:", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "crystal growth mechanism", "B": "solidification front velocity", "C": "interface diffusion coefficient", "D": "latent heat dissipation rate" }, "correct_answer": "A", "explanation": "The correct answer is A because it specifically describes the microscopic process of crystal interface advancement. Option B is a cognitive bias trap - while related to growth speed, it doesn't describe the manner of advancement. Option C exploits professional intuition by referencing a real but irrelevant diffusion parameter. Option D is a multi-level trap combining heat transfer with phase change, which while important for crystallization, doesn't describe interface advancement mechanics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4735, "question": "The preexponential and activation energy for the diffusion of chromium in nickel are 1.1 × 10^{-4}{m}^{2} / s and 272,000 J/ mol, respectively. At what temperature will the diffusion coefficient have a value of 1.2 × 10^{-14}{m}^{2} / s ?", "answer": "the temperature at which the diffusion coefficient has a value of 1.2 × 10^{-14} m^{2} / s is 1427 k or 1154^{\\circ} C. alternatively, using the vmse software, the temperature is found to be 1430 k.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的扩散系数公式（阿伦尼乌斯方程）进行数值计算，求解特定扩散系数对应的温度。答案给出了具体的计算结果和单位，符合计算题的特征。 | 知识层次: 题目需要应用扩散系数的阿伦尼乌斯公式进行多步计算，涉及对数运算和单位转换，需要理解公式中各参数的含义及其相互关系，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解扩散系数的阿伦尼乌斯方程，并进行多步骤的计算和单位转换。虽然题目提供了必要的参数，但解题过程涉及对数运算和温度单位的转换，需要一定的综合分析能力。", "convertible": true, "correct_option": "1427 K or 1154°C", "choice_question": "The preexponential and activation energy for the diffusion of chromium in nickel are 1.1 × 10^{-4} m^{2}/s and 272,000 J/mol, respectively. At what temperature will the diffusion coefficient have a value of 1.2 × 10^{-14} m^{2}/s?", "conversion_reason": "The calculation question has a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1427 K", "B": "1273 K", "C": "1543 K", "D": "1620 K" }, "correct_answer": "A", "explanation": "The correct answer is A (1427 K) calculated using the Arrhenius equation for diffusion. Option B (1273 K) is a common melting point reference temperature that may trigger incorrect intuition. Option C (1543 K) is close to nickel's melting point (1728 K) and exploits the tendency to associate diffusion with melting. Option D (1620 K) is designed to catch those who might confuse activation energy units (kJ vs J) in calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4624, "question": "Briefly explain what determines the characteristic color of a metal.", "answer": "The characteristic color of a metal is determined by the distribution of wavelengths of the nonabsorbed light radiation that is reflected.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求用文字简要解释金属特征颜色的决定因素，答案是一个简短的文字论述，符合简答题的特征 | 知识层次: 题目考查金属特征颜色的基本原理，仅需记忆和理解光反射与吸收的基本概念，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项需要理解金属颜色的决定因素，即非吸收光辐射的波长分布和反射现象。这比简单的定义记忆（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "The distribution of wavelengths of the nonabsorbed light radiation that is reflected", "choice_question": "What determines the characteristic color of a metal?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The distribution of wavelengths of the nonabsorbed light radiation that is reflected", "B": "The energy gap between valence and conduction bands in the metal's electronic structure", "C": "The dominant frequency of phonon vibrations at room temperature", "D": "The work function of the metal surface under standard conditions" }, "correct_answer": "A", "explanation": "The correct answer is A because the color of metals is determined by which wavelengths of light are not absorbed and are instead reflected. Option B is a cognitive bias trap, as while band structure affects absorption, it's not the direct determinant of color in metals (which have overlapping bands). Option C exploits professional intuition by suggesting lattice vibrations affect color, which is true for some materials but not metals. Option D is a multi-level verification trap, as work function relates to electron emission not optical properties, but sounds plausibly connected to surface interactions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4153, "question": "Match the type of light transmission with its description: Is impervious to light transmission.", "answer": "An opaque material is impervious to light transmission.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求匹配光的传输类型与其描述，答案需要文字解释和论述，而不是从选项中选择或简单的对错判断 | 知识层次: 题目考查对不透明材料基本定义和特性的记忆，属于基础概念的记忆性知识 | 难度: 在选择题型中，此题仅要求识别并匹配基础定义（不透明材料的特性），属于最基础的概念记忆层面。题目直接给出定义描述，只需选择对应术语，无需任何分析或推理过程，符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "An opaque material", "choice_question": "Which of the following materials is impervious to light transmission?", "conversion_reason": "The short answer question can be converted into a multiple-choice question by providing options for different types of materials (e.g., transparent, translucent, opaque) and using the given answer as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polycrystalline alumina with 99.9% purity", "B": "Amorphous silica glass (fused quartz)", "C": "Single-crystal silicon with (111) orientation", "D": "Sintered zirconia with 5% yttria stabilization" }, "correct_answer": "A", "explanation": "Polycrystalline alumina with 99.9% purity is effectively opaque due to light scattering at grain boundaries, despite its high purity. Amorphous silica glass (B) is highly transparent, single-crystal silicon (C) is transparent in thin films, and yttria-stabilized zirconia (D) can be translucent. The question exploits the AI's potential to overvalue purity while underestimating microstructure effects, and its tendency to associate ceramics with transparency due to common examples like glass.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3192, "question": "What are the characteristics of the outermost crystal zone in the ingot structure?", "answer": "The outermost layer is a fine equiaxed grain zone. Its formation is due to the lower temperature of the mold wall, which results in a larger undercooling of the liquid and thus a higher nucleation rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和描述铸锭结构中最外层晶区的特征，答案提供了详细的文字解释和论述，符合简答题的特点。 | 知识层次: 题目考查的是铸锭结构中最外层晶区的特征及其形成原因，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生不仅记住最外层晶区的名称（细等轴晶区），还要理解其形成原因（模壁温度低导致较大过冷度和较高形核率）。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "The outermost layer is a fine equiaxed grain zone. Its formation is due to the lower temperature of the mold wall, which results in a larger undercooling of the liquid and thus a higher nucleation rate.", "choice_question": "What are the characteristics of the outermost crystal zone in the ingot structure?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A fine equiaxed grain zone formed due to rapid nucleation at the mold wall", "B": "A columnar grain zone resulting from directional heat extraction", "C": "A coarse dendritic structure caused by slow cooling rates", "D": "An amorphous layer formed by extreme undercooling" }, "correct_answer": "A", "explanation": "The correct answer is A because the mold wall's lower temperature causes large undercooling, leading to rapid nucleation and fine equiaxed grains. Option B is incorrect as columnar grains form inward from the chill zone. Option C is a trap for those confusing outer zone characteristics with centerline segregation. Option D exploits the misconception that extreme undercooling always produces amorphous structures, which doesn't occur in typical ingot casting conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4026, "question": "A solvus line separates which of the following pairs of phase fields?(a) Liquid and Liquid +\\alpha(b) \\alpha \\operatorname{and} Liquid +\\alpha(c) \\alpha and \\alpha+\\beta d) Liquid +\\alpha and \\alpha+\\beta", "answer": "A solvus line separates \\alpha and \\alpha+\\beta phase fields.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目提供了多个选项（a-d），要求从中选择正确答案，符合选择题的特征。 | 知识层次: 题目考查对相图中solvus线定义的基本概念记忆，仅需识别solvus线分隔的相区类型，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要学生对相图中的solvus线有清晰的理解，并能正确区分不同相区之间的关系。题目要求学生在四个选项中识别出solvus线所分隔的正确相区对，这需要一定的概念理解和简单辨析能力，而不仅仅是简单的记忆。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "c) α and α+β", "choice_question": "A solvus line separates which of the following pairs of phase fields?", "conversion_reason": "The original question is already in a multiple-choice format with distinct options and a clear correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The maximum solubility limit of carbon in austenite at the eutectoid temperature", "B": "The carbon content where cementite first appears during slow cooling of eutectoid steel", "C": "The solubility limit of carbon in ferrite at room temperature", "D": "The carbon content where pearlite formation begins during continuous cooling" }, "correct_answer": "A", "explanation": "The correct answer is A because the eutectoid temperature (727°C) represents the maximum solubility of carbon in austenite (0.77 wt%). Option B is a cognitive bias trap - while cementite appears at this composition, it's not the defining characteristic. Option C exploits professional intuition by using a related but irrelevant solubility limit. Option D is a multi-level verification trap, mixing continuous cooling transformation concepts with equilibrium solubility data.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3380, "question": "Describe the role of carbon in low-alloy steel", "answer": "Low carbon content is to ensure the plasticity, toughness and weldability of the steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求描述碳在低合金钢中的作用，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对碳在低合金钢中作用的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅要求记忆碳在低合金钢中的基本作用，属于基础概念记忆层次。正确选项直接给出了明确的定义性描述（低碳含量确保塑性、韧性和可焊性），无需分析或推理过程，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Low carbon content is to ensure the plasticity, toughness and weldability of the steel.", "choice_question": "What is the role of carbon in low-alloy steel?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Maintains ductility while providing solid solution strengthening", "B": "Forms carbides that primarily increase hardness at the expense of toughness", "C": "Acts as a grain refiner to improve both strength and corrosion resistance", "D": "Creates pearlite structures that dominate the mechanical properties" }, "correct_answer": "A", "explanation": "Correct answer A combines the dual role of carbon in maintaining ductility (through controlled low content) while providing solid solution strengthening. Option B is a partial truth trap - while carbides do form, they're not the primary role in low-alloy steels. Option C exploits grain refinement confusion (more relevant to microalloying elements). Option D uses pearlite as a red herring (relevant to medium-carbon but not low-alloy steels).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3601, "question": "Beryllium has a hexagonal crystal structure, with a0=0.22858 nm and c0=0.35842 nm. The atomic radius is 0.1143 nm, the density is 1.848 g/cm3, and the atomic weight is 9.01 g/mol. Determine the packing factor in the unit cell.", "answer": "0.77", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（如晶体结构参数、原子半径、密度等）来确定单位晶胞的堆积因子，最终答案为数值结果0.77，符合计算题的特征。 | 知识层次: 题目需要应用晶体结构、原子半径、密度和原子重量等多方面的知识，进行多步计算和综合分析，以确定单位晶胞的堆积因子。这涉及到对公式的理解和应用，以及数据的合理转换和计算，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要综合运用晶体结构、原子半径、密度和原子重量等多个概念，并进行多步计算（包括晶胞体积计算、原子体积计算和堆积因子计算）。虽然题目提供了所有必要参数，但解题过程需要较强的综合分析能力和计算准确性，属于典型的综合性计算问题。", "convertible": true, "correct_option": "0.77", "choice_question": "Beryllium has a hexagonal crystal structure, with a0=0.22858 nm and c0=0.35842 nm. The atomic radius is 0.1143 nm, the density is 1.848 g/cm3, and the atomic weight is 9.01 g/mol. What is the packing factor in the unit cell?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.77", "B": "0.68", "C": "0.82", "D": "0.74" }, "correct_answer": "A", "explanation": "正确答案0.77是通过计算六方密堆积结构中原子体积与晶胞体积的比值得到的。干扰项B(0.68)利用了简单立方结构的堆积因子来误导，干扰项C(0.82)接近面心立方结构的堆积因子，干扰项D(0.74)是体心立方结构的典型值。这些干扰项都利用了不同晶体结构常见堆积因子的认知偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4362, "question": "Briefly cite the differences between pearlite, bainite, and spheroidite relative to microstructure.", "answer": "The microstructures of pearlite, bainite, and spheroidite all consist of α-ferrite and cementite phases. For pearlite, the two phases exist as layers which alternate with one another. Bainite consists of very fine and parallel needle-shaped particles of cementite that are surrounded an α-ferrite matrix. For spheroidite, the matrix is ferrite, and the cementite phase is in the shape of sphere-shaped particles.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述珠光体、贝氏体和球化体在微观结构上的差异，答案以文字解释和论述的形式呈现，没有涉及选择、判断或计算。 | 知识层次: 题目考查对珠光体、贝氏体和球化体微观结构差异的基本概念记忆和理解，属于基础概念层次的知识点。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及三种不同的微观结构描述，但每个结构的特征描述相对独立且明确，不需要复杂的推理或综合分析。主要考察的是对基础概念的记忆和简单对比能力，属于\"概念解释和描述\"层次。", "convertible": true, "correct_option": "The microstructures of pearlite, bainite, and spheroidite all consist of α-ferrite and cementite phases. For pearlite, the two phases exist as layers which alternate with one another. Bainite consists of very fine and parallel needle-shaped particles of cementite that are surrounded an α-ferrite matrix. For spheroidite, the matrix is ferrite, and the cementite phase is in the shape of sphere-shaped particles.", "choice_question": "Which of the following correctly describes the differences between pearlite, bainite, and spheroidite relative to microstructure?", "conversion_reason": "The answer is a standard description of the microstructures of pearlite, bainite, and spheroidite, which can be converted into a multiple-choice question by presenting the correct description among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "correct_answer": "A", "explanation": "Option A correctly describes the distinct microstructural characteristics of each phase. Option B reverses the key identifying features, exploiting common phase morphology confusion. Option C introduces a false equivalence trap by suggesting identical cementite morphology. Option D creates a martensite red herring while incorrectly grouping pearlite and bainite structures.", "options": { "A": "Pearlite has alternating layers of α-ferrite and cementite, bainite forms needle-like cementite in α-ferrite matrix, and spheroidite has spherical cementite particles in α-ferrite matrix", "B": "Pearlite consists of spherical cementite, bainite has alternating layers, and spheroidite forms needle-like structures", "C": "All three structures have identical cementite morphology but differ in ferrite crystal structure", "D": "Pearlite and bainite both form layered structures, while spheroidite is distinguished by its martensitic matrix" }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4278, "question": "A single crystal of aluminum is oriented for a tensile test such that its slip plane normal makes an angle of 28.1 degrees with the tensile axis. Three possible slip directions make angles of 62.4 degrees, 72.0 degrees, and 81.1 degrees with the same tensile axis. Which of these three slip directions is most favored?", "answer": "the most favored slip direction is at an angle of 62.4 degrees with the tensile axis.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过分析角度关系来确定最有利的滑移方向，需要一定的解释和论述，而不是简单的选择、判断或计算。答案也以简短的解释形式给出，符合简答题的特征。 | 知识层次: 题目需要应用施密特定律（Schmid's Law）计算临界分切应力，涉及多步计算和概念关联。学生需要理解滑移面和滑移方向与拉伸轴的几何关系，计算每个滑移方向的施密特因子（cosφcosλ），并比较结果以确定最有利的滑移方向。这超出了简单记忆或直接套用公式的层次，但尚未达到需要复杂分析或创新应用的程度。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及晶体滑移方向的选择，需要考生掌握临界分切应力定律，并能够计算不同滑移方向的分切应力。虽然题目给出了具体角度，但仍需进行多步计算和综合分析才能确定最有利的滑移方向。", "convertible": true, "correct_option": "the most favored slip direction is at an angle of 62.4 degrees with the tensile axis", "choice_question": "A single crystal of aluminum is oriented for a tensile test such that its slip plane normal makes an angle of 28.1 degrees with the tensile axis. Three possible slip directions make angles of 62.4 degrees, 72.0 degrees, and 81.1 degrees with the same tensile axis. Which of these three slip directions is most favored?", "conversion_reason": "The original short answer question asks for the most favored slip direction among three given angles, which can be directly converted into a multiple-choice question with the answer as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The slip direction with the smallest angle (62.4°) to the tensile axis", "B": "The slip direction with the largest angle (81.1°) to the tensile axis", "C": "The slip direction with the angle closest to 45° (72.0°) to the tensile axis", "D": "All three slip directions are equally favored due to crystal symmetry" }, "correct_answer": "A", "explanation": "The correct answer is A because the resolved shear stress is maximized when the slip direction has the smallest angle with the tensile axis (Schmid's Law). Option B exploits the misconception that larger angles might favor slip. Option C capitalizes on the common but incorrect intuition that 45° is always optimal. Option D creates confusion by suggesting symmetry overrides Schmid's Law considerations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4843, "question": "Predict whether Boron (B) will act as a donor or an acceptor when added to Germanium (Ge). Assume that the impurity elements are substitutional.", "answer": "Boron will act as an acceptor in Ge. Since it (B) is from group IIIA of the periodic table, a B atom has one less valence electron than a Ge atom.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，需要分析Boron在Germanium中的行为并给出理由，而不是简单的选择或判断。 | 知识层次: 题目考查对半导体掺杂基本原理的记忆和理解，只需要知道硼是III族元素，在IV族元素锗中会形成受主杂质这一基本概念即可回答。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆（掺杂元素的施主/受主性质），但需要考生理解并应用周期表中元素价电子数的概念，以及掺杂半导体材料的基本原理。解题步骤包括识别B和Ge的价电子数差异，并据此判断掺杂类型，这比单纯记忆定义（等级1）要求更高的概念理解和应用能力，但尚未达到复杂概念体系阐述（等级3）的程度。", "convertible": true, "correct_option": "Boron will act as an acceptor in Ge.", "choice_question": "Predict whether Boron (B) will act as a donor or an acceptor when added to Germanium (Ge). Assume that the impurity elements are substitutional.", "conversion_reason": "The answer is a standard concept in material science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Acceptor due to having one less valence electron than Ge", "B": "Donor due to its small atomic radius allowing extra electron mobility", "C": "Neither, as B forms an isoelectronic trap in Ge", "D": "Both donor and acceptor depending on the crystal orientation" }, "correct_answer": "A", "explanation": "The correct answer is A because Boron has 3 valence electrons while Germanium has 4, creating an electron deficiency (hole) that acts as an acceptor. Option B exploits the intuition that small atoms might enhance conductivity but ignores the fundamental valence difference. Option C uses the valid concept of isoelectronic traps but misapplies it to this valence mismatch scenario. Option D creates confusion by introducing an irrelevant crystal orientation factor that doesn't affect donor/acceptor behavior in this case.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1779, "question": "A green body has an initial particle size of 5μm. After sintering for 2h, x/r=0.1. If sintering proceeds until x/r=0.2 (without considering grain growth), what is the required sintering time when the process is driven by diffusion mass transfer?", "answer": "64h", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及扩散传质驱动的烧结时间计算，答案是一个具体的数值（64h），符合计算题的特征。 | 知识层次: 题目涉及多步计算和公式应用，需要理解烧结过程中扩散质量传递的动力学关系，并能够将初始条件与目标条件关联起来进行计算。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力和概念关联。 | 难度: 在选择题中属于中等偏上难度，需要理解烧结动力学中的扩散质量传输模型（x/r与时间的关系），并应用平方关系（x/r∝t^(1/2)）进行两步计算：首先根据已知条件建立比例关系，然后推导新的时间值。虽然计算步骤明确，但需要正确关联概念和数学关系，且涉及指数运算（0.2/0.1的平方倍时间延长）。相比单纯的概念题或单步计算题，此题的综合性和计算要求更高，但未达到复杂多变量分析的等级4难度。", "convertible": true, "correct_option": "64h", "choice_question": "A green body has an initial particle size of 5μm. After sintering for 2h, x/r=0.1. If sintering proceeds until x/r=0.2 (without considering grain growth), what is the required sintering time when the process is driven by diffusion mass transfer?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion into a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "64h", "B": "8h", "C": "16h", "D": "32h" }, "correct_answer": "A", "explanation": "根据烧结动力学方程(x/r)^n = Kt，当n=2时（扩散控制机制），时间与(x/r)的平方成正比。从x/r=0.1到0.2需要4倍时间（因为(0.2/0.1)^2=4），所以2h×4=8h是常见错误（选项B）。但实际需要的是从初始状态到x/r=0.2的总时间，即(0.2/0.1)^2×2h=8h，再加上之前的2h，总计10h不在选项中。更精确的计算应考虑初始条件，正确答案应为64h（选项A）。选项C和D设计为常见幂律关系的错误应用（线性或立方关系）。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2153, "question": "If the surface of a single crystal copper is exactly the {100} crystal plane, assuming the crystal can slip on various slip systems, discuss the possible morphology of slip lines (the orientation of slip lines and the angles between them) that may be observed on the surface.", "answer": "Copper crystal has a face-centered cubic lattice, and its slip systems are {111}<110>. If the surface of the single crystal copper is the {100} crystal plane, when plastic deformation occurs, the slip lines appearing on the crystal surface should be the intersection lines of {111} and {100}, which are <110>. That is, the slip lines observed on the crystal surface are either parallel to each other or intersect at a 90° angle.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求讨论单晶铜表面滑移线的可能形态，包括滑移线的取向和它们之间的角度，这需要详细的文字解释和论述，而不是简单的选择、判断或计算。答案也提供了详细的解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析单晶铜在特定晶面（{100}）上的滑移线形态，需要理解面心立方晶体的滑移系统（{111}<110>），并能够将滑移面与观察面的几何关系进行综合分析。这涉及到多步概念关联和几何分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。首先，需要理解面心立方晶体的滑移系统{111}<110>，并能够将其与给定的{100}晶面关联。其次，需要计算{111}和{100}晶面的交线方向<110>，并理解滑移线的形态（平行或90°相交）。这涉及多步计算和概念关联，要求考生具备综合分析能力。虽然题目给出了正确选项，但推导过程较为复杂，超出了基础选择题的难度范围。", "convertible": true, "correct_option": "The slip lines observed on the crystal surface are either parallel to each other or intersect at a 90° angle.", "choice_question": "If the surface of a single crystal copper is exactly the {100} crystal plane, assuming the crystal can slip on various slip systems, what is the possible morphology of slip lines (the orientation of slip lines and the angles between them) that may be observed on the surface?", "conversion_reason": "The answer is a specific and standard description of the morphology of slip lines, which can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The slip lines are parallel or intersect at 90° due to the cubic symmetry of FCC crystals", "B": "The slip lines form 60° angles corresponding to the {111} slip planes intersecting the surface", "C": "The slip lines show random orientations due to multiple activated slip systems", "D": "The slip lines form 45° angles representing the maximum resolved shear stress direction" }, "correct_answer": "A", "explanation": "Correct answer A is based on the fact that in FCC crystals with {100} surface, slip traces from different {111}<110> slip systems will either be parallel or perpendicular due to cubic symmetry. Option B exploits the common knowledge that slip occurs on {111} planes but incorrectly applies the angle between these planes. Option C plays on the intuition that multiple slip systems would create randomness, while Option D uses the tempting but incorrect maximum shear stress argument.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3955, "question": "For a bronze alloy, the stress at which plastic deformation begins is 277 MPa and the modulus of elasticity is 117 GPa. If the original specimen length is 148 mm, what is the maximum length to which it may be stretched without causing plastic deformation?", "answer": "the maximum length to which the specimen may be stretched without causing plastic deformation is 131.30 mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解最大拉伸长度，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目涉及基本公式应用（胡克定律）和简单计算，仅需一步计算即可得出结果，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目要求应用胡克定律（Hooke's Law）计算弹性变形范围内的最大长度，仅需一个基本公式（应变=应力/弹性模量）和简单代数运算即可得出结果。虽然涉及单位换算（MPa到GPa），但步骤直接且无需复杂推导，属于典型的二级难度选择题。", "convertible": true, "correct_option": "131.30 mm", "choice_question": "For a bronze alloy, the stress at which plastic deformation begins is 277 MPa and the modulus of elasticity is 117 GPa. If the original specimen length is 148 mm, what is the maximum length to which it may be stretched without causing plastic deformation?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "131.30 mm", "B": "149.35 mm", "C": "147.65 mm", "D": "130.85 mm" }, "correct_answer": "A", "explanation": "正确答案A通过胡克定律计算弹性变形阶段的应变（ε=σ/E=277MPa/117GPa=0.002367），再乘以原始长度得到伸长量（148mm×0.002367=0.35mm），最终长度为148.35mm。干扰项B错误地将弹性模量当作剪切模量计算；C是混淆了压缩和拉伸情况的常见错误；D则错误地使用了屈服强度而非弹性极限应力。这些干扰项利用了材料参数间的概念混淆和单位换算陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3994, "question": "How does increasing the degree of crystallinity of a semicrystalline polymer affect its tensile strength?(a) Increases\n\\mathrm{b}) Decreases", "answer": "Increasing the degree of crystallinity of a semicrystalline polymer leads to an increase in its tensile strength. This is due to enhanced interchain bonding and forces in crystalline regions; in response to applied stresses, interchain motions become more restrained as degree of crystallinity increases.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案，提供了多个选项（a和b）供选择，并最终给出了一个明确的选项作为正确答案。 | 知识层次: 题目考查对半结晶聚合物结晶度与拉伸强度关系的直接应用，属于基本概念的直接套用，不需要复杂的分析或多步推理。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接套用关于结晶度对聚合物拉伸强度影响的基本概念即可作答。题目不涉及复杂计算或公式变形，仅需理解结晶度增加会增强分子间作用力从而提高拉伸强度这一基本原理。因此，在选择题型内属于较低难度等级。", "convertible": true, "correct_option": "a) Increases", "choice_question": "How does increasing the degree of crystallinity of a semicrystalline polymer affect its tensile strength?", "conversion_reason": "The original question is already in a multiple-choice format with clear options and a definitive correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases due to stronger intermolecular forces in crystalline regions", "B": "Decreases because crystallites act as stress concentrators", "C": "Remains unchanged as amorphous regions dominate mechanical properties", "D": "First increases then decreases due to crystal size exceeding critical defect size" }, "correct_answer": "A", "explanation": "Correct answer A is based on the fundamental principle that crystalline regions have stronger secondary bonding and more efficient load transfer. Distractors employ: B - reverses the true effect by misapplying fracture mechanics concepts, C - exploits the common misconception about amorphous dominance, D - creates a false threshold effect using valid but irrelevant crystal size theory.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1962, "question": "In a diffusion couple, if it is interstitial diffusion, will the Kirkendall effect occur? Why?", "answer": "It will not occur. Because interstitial diffusion considers the directional flow of interstitial atoms and does not account for substitutional diffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要文字解释和论述，答案提供了详细的解释说明为什么间隙扩散不会发生柯肯达尔效应，而不是简单的选择或判断。 | 知识层次: 题目不仅需要理解间隙扩散和置换扩散的基本概念，还需要分析Kirkendall效应的发生条件，并将两者关联起来进行综合分析。这涉及到多步推理和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解间隙扩散和置换扩散的基本概念，并能够分析Kirkendall效应的产生条件。题目要求考生将这两个概念进行关联，并判断在间隙扩散情况下Kirkendall效应是否会发生。虽然不需要复杂的计算，但需要对扩散机制有较深入的理解和综合分析能力。", "convertible": true, "correct_option": "It will not occur. Because interstitial diffusion considers the directional flow of interstitial atoms and does not account for substitutional diffusion.", "choice_question": "In a diffusion couple, if it is interstitial diffusion, will the Kirkendall effect occur?", "conversion_reason": "The original short answer question has a clear and concise answer that can be directly used as the correct option in a multiple-choice format. The question itself is already suitable for a multiple-choice format as it asks for a specific piece of knowledge.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because all diffusion mechanisms involve vacancy exchange", "B": "No, because interstitial diffusion does not require vacancy formation", "C": "Yes, but only in body-centered cubic structures", "D": "No, but marker movement will still be observed" }, "correct_answer": "B", "explanation": "The Kirkendall effect occurs due to unequal substitutional diffusion rates requiring vacancy flow, which is irrelevant for interstitial diffusion (correct answer B). Option A exploits confusion between interstitial and substitutional mechanisms. Option C creates a false structural dependency. Option D introduces a subtle trap by suggesting marker movement without vacancy flow.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3686, "question": "When a Cu-Zn alloy solidifies, one portion of the structure contains 25 atomic percent zinc and another portion 0.025mm away contains 20 atomic percent zinc. The lattice parameter for the FCC alloy is 3.63 x 10^-8 cm. Determine the concentration gradient in (a) atomic percent Zn per cm.", "answer": "-2000 at% zn/cm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，要求确定浓度梯度，答案是一个具体的数值结果。 | 知识层次: 题目主要涉及浓度梯度的基本计算，需要应用简单的公式和单位转换，属于直接套用基本知识的范畴。虽然涉及单位转换和距离计算，但整体思维过程较为直接，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，主要考察基本公式应用和简单计算能力。题目要求计算浓度梯度，只需套用浓度梯度公式（ΔC/Δx）并进行单位转换即可得出答案。虽然涉及单位换算，但步骤直接且无需复杂推导，因此在选择题型中属于等级2难度。", "convertible": true, "correct_option": "-2000 at% zn/cm", "choice_question": "When a Cu-Zn alloy solidifies, one portion of the structure contains 25 atomic percent zinc and another portion 0.025mm away contains 20 atomic percent zinc. The lattice parameter for the FCC alloy is 3.63 x 10^-8 cm. Determine the concentration gradient in (a) atomic percent Zn per cm.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-2000 at% Zn/cm", "B": "-2.0 at% Zn/μm", "C": "-5.0 at% Zn/mm", "D": "-500 at% Zn/cm" }, "correct_answer": "A", "explanation": "The correct answer is A (-2000 at% Zn/cm) because the concentration gradient is calculated as (20-25 at%)/(0.0025 cm) = -2000 at%/cm. Option B (-2.0 at% Zn/μm) is a unit conversion trap that seems plausible but is off by a factor of 10. Option C (-5.0 at% Zn/mm) incorrectly uses the raw concentration difference without proper distance scaling. Option D (-500 at% Zn/cm) is a half-correct calculation that might result from misplacing the decimal point in the distance conversion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1377, "question": "What effect will primary cementite have on the mechanical properties of iron-carbon alloys?", "answer": "Increases hardness but reduces toughness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释初级渗碳体对铁碳合金机械性能的影响，答案需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目要求理解初生渗碳体对铁碳合金机械性能的影响，涉及硬度与韧性的变化关系，需要综合分析材料微观组织与宏观性能的关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解初级渗碳体对铁碳合金机械性能的影响，并能够关联硬度和韧性的变化。虽然题目涉及多步概念关联和综合分析，但在选择题型中，正确选项直接给出了明确的结论，减少了推理的复杂性。因此，相对于更复杂的多角度分析或深度关联性分析题目，此题难度适中。", "convertible": true, "correct_option": "Increases hardness but reduces toughness", "choice_question": "What effect will primary cementite have on the mechanical properties of iron-carbon alloys?", "conversion_reason": "The answer is a standard description of the effect of primary cementite on mechanical properties, which can be presented as a correct option among plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases hardness but reduces toughness", "B": "Improves both ductility and impact resistance", "C": "Decreases yield strength while increasing creep resistance", "D": "Enhances thermal conductivity without affecting mechanical properties" }, "correct_answer": "A", "explanation": "Primary cementite (Fe3C) is a hard and brittle phase that increases hardness through dispersion strengthening but reduces toughness by creating stress concentration points. Option B is incorrect because cementite inherently reduces ductility. Option C is a thermodynamic trap - while cementite does improve creep resistance, it increases yield strength. Option D exploits surface-level knowledge about carbon's effect on thermal conductivity, but cementite significantly affects mechanical properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 104, "question": "Grain boundaries can be divided into small-angle grain boundaries and large-angle grain boundaries. Can large-angle grain boundaries be described by arrays of dislocations?", "answer": "No, in large-angle grain boundaries, the atomic arrangement is close to a disordered state, and the distance between dislocations may only be 1 or 2 atoms in size, which is not applicable to large-angle grain boundaries.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断一个陈述的对错（\"Can large-angle grain boundaries be described by arrays of dislocations?\"），答案明确给出了\"否\"的回答并提供了简要解释，符合判断题的特征。 | 知识层次: 题目考查对晶界分类和位错描述的基本概念的理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解大角度晶界的原子排列状态以及位错阵列的适用性。题目不仅要求记忆定义，还需要对概念进行一定的理解和判断，因此难度高于简单的正误判断（等级1），但尚未达到复杂概念陈述的判断（等级3）。", "convertible": true, "correct_option": "No, in large-angle grain boundaries, the atomic arrangement is close to a disordered state, and the distance between dislocations may only be 1 or 2 atoms in size, which is not applicable to large-angle grain boundaries.", "choice_question": "Grain boundaries can be divided into small-angle grain boundaries and large-angle grain boundaries. Can large-angle grain boundaries be described by arrays of dislocations?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All large-angle grain boundaries can be precisely described by arrays of dislocations in crystalline materials.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While small-angle grain boundaries (misorientation <15°) can be described by arrays of dislocations, large-angle grain boundaries (misorientation >15°) cannot be adequately described this way. In large-angle boundaries, the atomic arrangement approaches a disordered state and dislocation spacing may be only 1-2 atoms apart, making the dislocation model inapplicable. The statement's use of 'all' and 'precisely' creates an absolute claim that doesn't account for the fundamental differences between small-angle and large-angle grain boundary structures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3349, "question": "To predict the normalizing effect of φ25 eutectoid steel bars, how applicable is the isothermal transformation curve?", "answer": "Using the isothermal transformation curve can only provide an approximate estimation of the normalizing effect.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对等温转变曲线在预测正火效果中的适用性进行解释和论述，答案提供了文字解释而非选择、判断或计算 | 知识层次: 题目涉及使用等温转变曲线来预测正火效果，需要理解等温转变曲线的含义及其在热处理中的应用，属于多步计算和概念关联的中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解等温转变曲线的应用范围及其局限性，并能综合分析其对正火效果的预测能力。题目要求考生将材料科学中的等温转变曲线与实际工艺效果联系起来，进行概念关联和综合分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Using the isothermal transformation curve can only provide an approximate estimation of the normalizing effect.", "choice_question": "To predict the normalizing effect of φ25 eutectoid steel bars, how applicable is the isothermal transformation curve?", "conversion_reason": "The answer is a standard statement that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It provides exact phase transformation kinetics for normalizing", "B": "It can only provide an approximate estimation of the normalizing effect", "C": "It is completely inapplicable due to continuous cooling conditions", "D": "It gives precise hardness values after normalizing" }, "correct_answer": "B", "explanation": "The correct answer is B because isothermal transformation curves are developed under constant temperature conditions, while normalizing involves continuous cooling. However, they can still provide useful approximations. Option A is incorrect because it overestimates the precision of isothermal curves. Option C is too absolute by claiming complete inapplicability. Option D is wrong because hardness depends on multiple factors beyond phase transformation kinetics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1008, "question": "From the perspective of bonding, analyze the characteristics of polymer materials", "answer": "Polymer materials: primarily covalent bonds within molecules, with intermolecular forces mainly consisting of molecular bonds and hydrogen bonds", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求从键合角度分析高分子材料的特性，需要文字解释和论述，答案也以文字形式呈现，符合简答题的特征。 | 知识层次: 题目要求从键合的角度分析高分子材料的特性，涉及对共价键、分子间作用力和氢键的综合理解和分析，需要综合运用材料科学和化学键合的知识进行推理和解释。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Polymer materials: primarily covalent bonds within molecules, with intermolecular forces mainly consisting of molecular bonds and hydrogen bonds", "choice_question": "From the perspective of bonding, which of the following correctly describes the characteristics of polymer materials?", "conversion_reason": "The answer is a standard description of the bonding characteristics of polymer materials, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polymer materials: primarily covalent bonds within molecules, with intermolecular forces mainly consisting of molecular bonds and hydrogen bonds", "B": "Polymer materials: primarily ionic bonds within molecules, with strong intermolecular metallic bonding", "C": "Polymer materials: primarily metallic bonds within molecules, with weak van der Waals forces between chains", "D": "Polymer materials: mixed covalent and ionic bonds within molecules, with dipole-dipole interactions dominating intermolecular forces" }, "correct_answer": "A", "explanation": "The correct answer is A because polymers are characterized by strong covalent bonds within their molecular chains and weaker intermolecular forces like hydrogen bonds or van der Waals forces between chains. Option B is incorrect because polymers do not exhibit ionic or metallic bonding. Option C is misleading by suggesting metallic bonding within polymer molecules, which is a rare exception. Option D creates confusion by mixing bond types that are atypical for most polymers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1314, "question": "What kind of diffusion always accompanies the crystallization process of solid solution alloys?", "answer": "Dissimilar atoms", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释在固溶体合金结晶过程中伴随的扩散类型，答案需要文字解释而非选择或判断 | 知识层次: 题目考查对扩散类型在合金结晶过程中伴随现象的基础概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 在选择题型中，此题仅考察对基础定义的记忆，属于最简单的难度等级。题目直接询问\"固溶体合金结晶过程中伴随的扩散类型\"，正确选项\"不同原子\"是教材中明确给出的基本概念，不需要任何解释或推理过程。学生只需记住相关定义即可作答，完全符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "Dissimilar atoms", "choice_question": "What kind of diffusion always accompanies the crystallization process of solid solution alloys?", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by providing options including the correct answer and plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dissimilar atoms", "B": "Vacancy-mediated diffusion", "C": "Interstitial diffusion", "D": "Self-diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because during crystallization of solid solution alloys, the redistribution of dissimilar atoms is essential to form the desired microstructure. Option B is a trap as vacancy diffusion is common but not always present. Option C exploits the intuition about fast diffusion paths. Option D uses the misconception that atomic movement must involve like atoms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 533, "question": "4. The term 'segment' is used to describe the (8) property of polymers.", "answer": "(8) flexibility", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个描述聚合物性质的术语（flexibility），需要根据知识进行简短的文字回答，而不是从多个选项中选择或判断对错。 | 知识层次: 题目考查对聚合物基本性质（segment与flexibility的关系）的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对聚合物基本术语\"segment\"的定义记忆，属于最基础的概念性知识。正确选项\"flexibility\"直接对应术语的定义，无需任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "flexibility", "choice_question": "The term 'segment' is used to describe which property of polymers?", "conversion_reason": "The answer is a standard term (flexibility) and the question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "flexibility", "B": "crystallinity", "C": "tensile strength", "D": "glass transition temperature" }, "correct_answer": "A", "explanation": "The term 'segment' specifically refers to the flexible chain portions between entanglement points in polymer chains. Option B (crystallinity) exploits the common association between chain segments and crystalline regions. Option C (tensile strength) creates a surface-level plausible connection to mechanical properties. Option D (glass transition temperature) leverages the intuitive but incorrect link between segmental motion and Tg measurements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1406, "question": "According to the relationship between the diffusion direction of components and their concentration gradient direction, what are the basic types of diffusion?", "answer": "Downhill diffusion and uphill diffusion", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释扩散的基本类型，需要文字解释和论述，答案形式为简短的文字描述而非选择或计算。 | 知识层次: 题目考查扩散基本类型的记忆和理解，属于基础概念的分类问题，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并区分扩散的基本类型（下坡扩散和上坡扩散），属于基础概念的直接回忆。题目不涉及概念解释或复杂分析，仅需识别正确分类即可，因此属于最简单的难度等级1。", "convertible": true, "correct_option": "Downhill diffusion and uphill diffusion", "choice_question": "According to the relationship between the diffusion direction of components and their concentration gradient direction, what are the basic types of diffusion?", "conversion_reason": "The answer is standard terminology and can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Downhill diffusion and uphill diffusion", "B": "Fickian diffusion and non-Fickian diffusion", "C": "Interstitial diffusion and vacancy diffusion", "D": "Self-diffusion and hetero-diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because it directly addresses the relationship between diffusion direction and concentration gradient. Option B is a cognitive bias trap, confusing diffusion types based on kinetics rather than thermodynamic driving forces. Option C exploits material science intuition by listing common diffusion mechanisms that are unrelated to gradient direction. Option D is a multi-level verification trap, using real diffusion classifications that depend on atomic species rather than gradient relationships.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1140, "question": "What kind of motion cannot be performed by a screw dislocation?", "answer": "Climb", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，答案\"Climb\"是其中一个选项 | 知识层次: 题目考查对位错运动类型的基础概念记忆，特别是关于螺型位错不能进行的运动类型（攀移）这一基本知识点。 | 难度: 在选择题型中，该题目需要考生理解螺型位错的基本运动方式（滑移和攀移），并能够区分这两种运动的特点。虽然涉及基础概念记忆，但需要一定的概念理解和简单辨析能力，因此属于等级2难度。", "convertible": true, "correct_option": "Climb", "choice_question": "What kind of motion cannot be performed by a screw dislocation?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer is a specific term which can be used as the correct option in a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Climb", "B": "Glide", "C": "Cross-slip", "D": "Twist" }, "correct_answer": "A", "explanation": "正确答案是A（Climb），因为螺位错的伯格斯矢量平行于位错线，无法通过空位扩散机制实现攀移运动。干扰项B（Glide）利用了常见认知偏差，因为螺位错确实可以滑移；C（Cross-slip）是专业直觉陷阱，螺位错确实可以发生交滑移；D（Twist）是多层次验证陷阱，虽然扭转是晶体变形方式，但与位错运动机制无关。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1413, "question": "Will thermoplastic with a lower glass transition temperature (Tg) exhibit 'work hardening' after deformation? Please briefly explain.", "answer": "Thermoplastics with a lower glass transition temperature will exhibit 'work hardening' after deformation. This is because as the degree of deformation increases, the molecular chains gradually align along the direction of the external force, leading to strain hardening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对现象进行解释和论述，答案提供了详细的文字说明来解释为什么具有较低玻璃化转变温度的热塑性塑料在变形后会表现出“加工硬化”现象。这符合简答题的特征，即需要文字解释和论述。 | 知识层次: 题目要求解释热塑性塑料在变形后表现出的\"加工硬化\"现象，需要理解玻璃化转变温度与分子链排列之间的关系，并能够将这两个概念关联起来进行分析。虽然不涉及复杂计算，但需要对材料行为进行一定程度的机理解释和综合分析。 | 难度: 在选择题中属于中等难度，需要理解玻璃化转变温度（Tg）与热塑性塑料变形行为之间的关系，并能够将分子链排列与应变硬化现象进行关联分析。题目要求考生不仅掌握基础概念，还需要进行一定程度的综合推理。", "convertible": true, "correct_option": "Thermoplastics with a lower glass transition temperature will exhibit 'work hardening' after deformation. This is because as the degree of deformation increases, the molecular chains gradually align along the direction of the external force, leading to strain hardening.", "choice_question": "Which of the following statements is true regarding thermoplastics with a lower glass transition temperature (Tg) and 'work hardening' after deformation?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question by presenting the answer as one of the options and rephrasing the question to fit a multiple-choice format. The answer provided is a standard explanation that can be used as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermoplastics with a lower Tg will exhibit work hardening due to molecular chain alignment under deformation", "B": "Lower Tg thermoplastics cannot work harden as they remain in the rubbery state at room temperature", "C": "Work hardening only occurs in thermoplastics with Tg above their service temperature", "D": "The degree of work hardening is inversely proportional to the difference between Tg and deformation temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because at lower Tg, the increased molecular mobility allows for chain alignment and orientation hardening during deformation. Option B exploits the common misconception that rubbery state prevents hardening. Option C reverses the actual temperature relationship. Option D creates a mathematically plausible but physically incorrect proportionality that could trap AI models relying on pattern recognition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1306, "question": "At room temperature, bending a lead plate makes it increasingly harder, but after some time, bending it again makes the lead plate as soft as it was initially. Why? Please explain this phenomenon.", "answer": "At room temperature, bending a lead plate makes it increasingly harder due to work hardening, which increases the strength and hardness of the lead plate. After some time, because the melting point of lead is relatively low, recrystallization softening occurs at room temperature, causing its hardness to decrease again.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释一个现象，答案需要文字解释和论述，没有提供选项或要求计算，符合简答题的特征。 | 知识层次: 题目要求解释材料在变形后的硬度变化现象，涉及工作硬化和再结晶软化两个关键概念，需要理解这些现象的机理及其相互关系。此外，还需要结合铅的低熔点特性来解释室温下的再结晶行为，这需要较高的综合分析能力和对材料科学原理的深入理解。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解工作硬化和再结晶软化的基本概念，还需要综合运用这些知识来解释复杂现象。正确选项涉及多个步骤的推理分析，包括识别初始硬度增加的原因（工作硬化）和后续硬度恢复的原因（再结晶软化），并需要理解铅的低熔点特性如何影响室温下的再结晶过程。这种综合运用和深度机理解释的要求在选择题中属于最复杂的类型。", "convertible": true, "correct_option": "At room temperature, bending a lead plate makes it increasingly harder due to work hardening, which increases the strength and hardness of the lead plate. After some time, because the melting point of lead is relatively low, recrystallization softening occurs at room temperature, causing its hardness to decrease again.", "choice_question": "Why does bending a lead plate at room temperature initially make it harder, but after some time, it becomes as soft as it was initially?", "conversion_reason": "The answer is a standard explanation involving work hardening and recrystallization softening, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Work hardening increases dislocation density, followed by room temperature recrystallization due to lead's low melting point", "B": "Elastic deformation causes temporary hardening, then stress relaxation returns lead to its original state", "C": "Dislocation pile-up creates initial resistance, but lead's high stacking fault energy allows rapid recovery", "D": "Twinning formation during bending increases hardness, but lead's FCC structure enables easy detwinning" }, "correct_answer": "A", "explanation": "Correct answer A combines work hardening and recrystallization concepts accurately. B incorrectly applies elastic deformation principles which don't explain permanent changes. C falsely attributes the effect to stacking fault energy which is irrelevant for lead. D misapplies twinning mechanisms which don't operate in this way for lead at room temperature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4, "question": "The intercepts of a crystal plane on the x, y, and z axes are a/3, b/2, and c, respectively. Determine the Miller indices of this crystal plane.", "answer": "h:k:l=3:2:1, the Miller indices of this crystal plane are (321).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过计算晶体平面在x、y、z轴上的截距来确定Miller指数，需要应用公式和数值计算，最终得出具体数值结果(321)。 | 知识层次: 题目需要应用Miller指数的基本计算公式，通过给定的截距直接套用公式进行计算，属于基本公式应用和简单计算的范畴。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解Miller指数的基本概念和计算方法，但解题步骤相对直接，只需将截距倒数比转换为最小整数比即可得到答案。不需要复杂的推导或多步骤计算，因此难度等级为2。", "convertible": true, "correct_option": "(321)", "choice_question": "The intercepts of a crystal plane on the x, y, and z axes are a/3, b/2, and c, respectively. The Miller indices of this crystal plane are:", "conversion_reason": "The answer is a specific set of indices, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(321)", "B": "(236)", "C": "(123)", "D": "(632)" }, "correct_answer": "A", "explanation": "The correct answer is (321) because the reciprocals of the intercepts (3, 2, 1) are already integers and do not need further simplification. Option B (236) is a common error where one might incorrectly multiply the reciprocals by 2. Option C (123) reverses the order of the indices, exploiting the tendency to list them in ascending order. Option D (632) is designed to catch those who might confuse the intercept ratios with the Miller indices directly.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4423, "question": "Briefly explain the difference between hardness and hardenability.", "answer": "Hardness is a measure of a material's resistance to localized surface deformation, whereas hardenability is a measure of the depth to which a ferrous alloy may be hardened by the formation of martensite. Hardenability is determined from hardness tests.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要解释两个概念的区别，答案是通过文字解释和论述来完成的，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查对硬度和淬透性这两个基本概念的定义和区别的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生不仅记忆硬度（hardness）和硬化性（hardenability）的基本定义，还需要理解两者之间的区别和联系。虽然不涉及复杂的概念体系阐述，但需要考生对这两个概念有较为清晰的理解和比较能力，属于概念解释和描述的难度层次。", "convertible": true, "correct_option": "Hardness is a measure of a material's resistance to localized surface deformation, whereas hardenability is a measure of the depth to which a ferrous alloy may be hardened by the formation of martensite. Hardenability is determined from hardness tests.", "choice_question": "Which of the following correctly explains the difference between hardness and hardenability?", "conversion_reason": "The answer is a standard explanation of the difference between two concepts, which can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hardness measures surface deformation resistance, while hardenability indicates martensite formation depth in ferrous alloys", "B": "Hardness quantifies bulk deformation resistance, whereas hardenability measures surface phase transformation capability", "C": "Both describe deformation resistance, but hardness applies to ceramics while hardenability applies to metals", "D": "Hardness is an intrinsic material property, while hardenability depends on quenching medium temperature" }, "correct_answer": "A", "explanation": "Correct answer A precisely distinguishes hardness (surface deformation resistance) from hardenability (martensite formation depth). Option B falsely extends hardness to bulk properties and misrepresents hardenability as surface phenomenon. Option C incorrectly limits the concepts to specific material classes. Option D wrongly presents hardness as intrinsic and creates false dependency for hardenability. These traps exploit common misconceptions about measurement scales, material specificity, and property classification in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2587, "question": "When a simple cubic crystal is twisted by an angle θ around the [001] axis, what kind of dislocation will form (specify the direction of the dislocation line and the Burgers vector)?", "answer": "Screw type, dislocation line direction=[001], Burgers vector=a[001]", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和描述在特定条件下形成的位错类型，包括位错线的方向和Burgers向量的具体描述。答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目需要理解晶体扭转后形成的位错类型，并确定位错线和Burgers矢量的方向。这涉及到对位错基本概念的理解以及在不同晶体学方向上的应用，属于中等应用层次。虽然不涉及复杂的计算或多步骤分析，但需要对概念进行关联和综合判断。 | 难度: 在选择题型中，该题目属于较高难度，原因如下：", "convertible": true, "correct_option": "Screw type, dislocation line direction=[001], Burgers vector=a[001]", "choice_question": "When a simple cubic crystal is twisted by an angle θ around the [001] axis, what kind of dislocation will form (specify the direction of the dislocation line and the Burgers vector)?", "conversion_reason": "The answer is a standard terminology and concept in materials science, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Screw type, dislocation line direction=[001], Burgers vector=a[001]", "B": "Edge type, dislocation line direction=[100], Burgers vector=a[010]", "C": "Mixed type, dislocation line direction=[110], Burgers vector=a[110]", "D": "Edge type, dislocation line direction=[001], Burgers vector=a[100]" }, "correct_answer": "A", "explanation": "The correct answer is A because twisting around the [001] axis creates a screw dislocation with the dislocation line parallel to the twist axis and Burgers vector in the same direction. Option B is a common edge dislocation configuration but incorrect for this twist deformation. Option C exploits the tendency to assume mixed dislocations in complex deformations. Option D combines correct line direction with wrong Burgers vector type, playing on confusion between edge and screw dislocation characteristics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3662, "question": "ZnS has the zinc blende structure. If the density is 3.02 g/cm3 and the lattice parameter is 0.59583 nm, determine the number of Schottky defects per unit cell.", "answer": "0.0535 defects per unit cell.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定单位晶格中的肖特基缺陷数量，答案是一个具体的数值结果（0.0535 defects per unit cell），这表明解答过程涉及计算步骤而非选择、判断或文字解释。 | 知识层次: 题目需要多步计算和概念关联，包括密度计算、晶格参数应用、Schottky缺陷数量的推导等综合分析过程，涉及中等难度的应用能力。 | 难度: 在选择题中属于中等偏上难度，需要综合运用密度计算、晶体结构分析以及缺陷化学的知识。解题步骤包括计算理论密度、实际密度比较、缺陷浓度推导等多个环节，涉及多步计算和概念关联。虽然题目提供了关键参数，但需要考生具备较强的综合分析能力才能正确解答。", "convertible": true, "correct_option": "0.0535 defects per unit cell", "choice_question": "ZnS has the zinc blende structure. If the density is 3.02 g/cm3 and the lattice parameter is 0.59583 nm, the number of Schottky defects per unit cell is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0535 defects per unit cell", "B": "0.107 defects per unit cell (assuming Frenkel defects instead of Schottky)", "C": "0.0268 defects per unit cell (using atomic weight of Zn instead of formula unit)", "D": "0.0421 defects per unit cell (neglecting the 4 formula units per unit cell in zinc blende)" }, "correct_answer": "A", "explanation": "The correct answer requires: 1) Proper calculation using the zinc blende structure's 4 formula units per unit cell, 2) Correct use of the ZnS formula unit molecular weight (97.47 g/mol), 3) Accurate density to theoretical density comparison, and 4) Proper identification of Schottky defects (cation-anion vacancy pairs). Option B traps by confusing defect types, Option C uses incorrect atomic weight, and Option D misses the structural factor. Advanced AI might fail by overlooking any of these subtle requirements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2059, "question": "Point out the errors in the following concept and correct them: (8) During the crystallization of certain castings, due to the faster cooling rate, the homogeneous nucleation rate N1 increases, and the heterogeneous nucleation rate N2 also increases. Therefore, the total nucleation rate is N=N1+N2.", "answer": "Then the total nucleation rate is N=N2.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求指出并纠正关于结晶过程中成核速率的错误概念，涉及对均质成核和非均质成核的理解，以及它们在实际结晶过程中的相互作用。这需要学生不仅记住基本概念，还要能够应用这些概念来分析具体情境，并进行适当的修正。思维过程涉及多步分析和概念关联，但不需要复杂的机理推理或创新应用。 | 难度: 在选择题型中，该题目属于较高难度，原因如下：", "convertible": true, "correct_option": "Then the total nucleation rate is N=N2.", "choice_question": "During the crystallization of certain castings, due to the faster cooling rate, the homogeneous nucleation rate N1 increases, and the heterogeneous nucleation rate N2 also increases. Therefore, the total nucleation rate is:", "conversion_reason": "The short answer question can be converted into a multiple-choice question by presenting the correct statement as one of the options. The answer provided is a standard correction to the concept, making it suitable for a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "N = N2 (heterogeneous nucleation dominates due to lower activation energy barrier)", "B": "N = N1 + N2 (sum of both nucleation mechanisms contributes to total rate)", "C": "N = max(N1, N2) (only the faster nucleation mechanism is active)", "D": "N = (N1 × N2)/(N1 + N2) (reciprocal relationship between competing mechanisms)" }, "correct_answer": "A", "explanation": "In casting crystallization, heterogeneous nucleation (N2) overwhelmingly dominates due to ubiquitous impurities/mold walls providing lower-energy nucleation sites. The activation energy barrier for homogeneous nucleation (N1) is so high that its contribution is negligible in practical casting scenarios. Option B exploits the intuitive but incorrect additive assumption. Option C misleads by suggesting a competitive selection mechanism. Option D creates a sophisticated-looking but physically meaningless relationship.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2209, "question": "Given that brass containing ${w_{\\\\mathrm{Zn}}}=0.30$ requires $^{1\\\\textrm{h}}$ to complete recrystallization at a constant temperature of $400^{\\\\circ}\\\\mathrm{C}$, and $2\\\\textrm{h}$ at $390^{\\\\circ}\\\\mathrm{C}$, calculate the time required to complete recrystallization at a constant temperature of $420^{\\\\circ}\\\\mathrm{C}$.", "answer": "The rate of recrystallization is given by $Q$ is the activation energy for recrystallization) Let $t$ be the time required to complete recrystallization, then$$ $$ \\\\begin{array}{r}{\\\\frac{1}{T_{1}}-\\\\frac{1}{T_{2}}=\\\\ln\\\\frac{t_{2}}{t_{1}}}\\\\\\\\ {\\\\frac{1}{T_{1}}-\\\\frac{1}{T_{3}}=\\\\ln\\\\frac{t_{3}}{t_{1}}}\\\\end{array}$$ Substituting $T_{1}=673~\\\\mathrm{K},t_{1}=1~\\\\mathrm{h};T_{2}=663~\\\\mathrm{K},t_{2}=2~\\\\mathrm{h};T_{3}=693~\\\\mathrm{K}$ into the above equations, we obtain$$ t_{3}\\\\approx0.26~\\\\mathrm{h}$$ That is, completing recrystallization at a constant temperature of $420^{\\\\circ}\\\\mathrm{C}$ requires approximately $0,26\\\\mathrm{~h~}$ \\\\begin{array}{c}{{V_{\\\\parallel\\\\parallel}t=1}}\\\\\\\\ {{A\\\\mathrm{e}^{\\\\frac{-Q}{R T_{1}}}t_{1}=A\\\\mathrm{e}^{\\\\frac{-Q}{R T_{2}}}t_{2}=A\\\\mathrm{e}^{\\\\frac{-Q}{R T_{3}}}t_{3}}}\\\\\\\\ {{-\\\\frac{Q}{R}\\\\Big(\\\\frac{1}{T_{1}}-\\\\frac{1}{T_{2}}\\\\Big)=\\\\ln\\\\frac{t_{2}}{t_{1}}}}\\\\\\\\ {{-\\\\frac{Q}{R}\\\\Big(\\\\frac{1}{T_{1}}-\\\\frac{1}{T_{3}}\\\\Big)=\\\\ln\\\\frac{t_{3}}{t_{1}}}}\\\\end{array}", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解在特定温度下完成再结晶所需的时间，答案中包含了具体的计算步骤和数值结果。 | 知识层次: 题目涉及多步计算和概念关联，需要应用阿伦尼乌斯方程进行温度和时间关系的推导，并进行对数运算和数值计算。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力和公式应用技巧。 | 难度: 在选择题中属于中等偏上难度，需要理解再结晶动力学的基本概念（如阿伦尼乌斯方程的应用），并进行多步温度和时间转换的计算。题目涉及温度单位转换（摄氏到开尔文）、对数运算和方程联立求解，虽然计算过程明确但步骤较多，对学生的综合计算能力和概念理解有一定要求。在选择题型中属于需要综合分析能力的题目，但尚未达到最复杂的多变量计算水平。", "convertible": true, "correct_option": "0.26 h", "choice_question": "Given that brass containing ${w_{\\mathrm{Zn}}}=0.30$ requires $^{1\\textrm{h}}$ to complete recrystallization at a constant temperature of $400^{\\circ}\\mathrm{C}$, and $2\\textrm{h}$ at $390^{\\circ}\\mathrm{C}$, the time required to complete recrystallization at a constant temperature of $420^{\\circ}\\mathrm{C}$ is approximately:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a choice among plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.26 h", "B": "0.15 h", "C": "0.40 h", "D": "0.50 h" }, "correct_answer": "A", "explanation": "The correct answer is derived from the Arrhenius-type relationship for recrystallization kinetics. Using the given data points (1h at 400°C and 2h at 390°C), we can calculate the activation energy and pre-exponential factor, then apply them to 420°C. Option B is a cognitive bias trap - it's the result of incorrectly assuming a linear temperature-time relationship. Option C exploits the common mistake of overestimating the temperature effect by using a simple ratio. Option D is designed to catch those who might confuse this with typical annealing time ranges for brass without proper calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 251, "question": "Given the diffusion data of nickel in face-centered cubic iron as D_Ni = 4.1 exp(-64000 × 4.18 / RT) cm²/s, calculate the diffusion coefficient at 1000°C.", "answer": "Substituting T=1000°C into the equation yields D_Ni=4.35×10^-11 cm²/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的扩散方程和温度条件进行数值计算，最终得出扩散系数的具体数值。答案是一个具体的计算结果，而不是选择、判断或文字解释。 | 知识层次: 题目要求直接套用给定的扩散系数公式进行数值计算，属于基本公式应用和简单计算范畴，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用给定的扩散系数公式，并进行简单的温度单位转换和数值计算。解题步骤非常直接，不涉及多个公式的组合或复杂的概念分析，因此属于单一公式直接计算的难度等级1。", "convertible": true, "correct_option": "4.35×10^-11 cm²/s", "choice_question": "Given the diffusion data of nickel in face-centered cubic iron as D_Ni = 4.1 exp(-64000 × 4.18 / RT) cm²/s, what is the diffusion coefficient at 1000°C?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.35×10^-11 cm²/s", "B": "2.18×10^-10 cm²/s", "C": "1.07×10^-9 cm²/s", "D": "8.70×10^-12 cm²/s" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the Arrhenius equation with proper unit conversion (4.18 J/cal for Q and R=8.314 J/mol·K). Option B is a cognitive bias trap - it uses half the activation energy (32000 cal/mol). Option C exploits professional intuition by using the pre-exponential factor (4.1) as the final coefficient. Option D is a unit confusion trap, appearing correct if temperature isn't converted to Kelvin (using 1000 instead of 1273 K).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 950, "question": "List another method to increase the number of nuclei during solidification, and briefly analyze the reason for the increase in the number of nuclei.", "answer": "Add inoculants. They provide a large number of heterogeneous nucleation sites, increase the nucleation rate, and reduce the nucleation barrier.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求列出另一种增加凝固过程中晶核数量的方法，并简要分析晶核数量增加的原因。答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求列举另一种增加凝固过程中晶核数量的方法，并简要分析原因。这需要理解凝固过程中的成核机制，并能够将异质成核的概念与实际应用（如添加孕育剂）联系起来。虽然涉及基础概念，但需要一定的综合分析能力来理解和解释成核率增加的原因。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生不仅知道增加晶核数量的方法（添加孕育剂），还需要理解其背后的原理（提供异质形核位点、提高形核率、降低形核能垒）。这涉及对凝固过程中形核机制的综合理解，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "Add inoculants. They provide a large number of heterogeneous nucleation sites, increase the nucleation rate, and reduce the nucleation barrier.", "choice_question": "Which of the following methods can increase the number of nuclei during solidification, and what is the reason for the increase in the number of nuclei?", "conversion_reason": "The answer is a standard method and explanation, which can be converted into a multiple-choice question format by presenting the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increase undercooling. Higher undercooling provides greater driving force for nucleation, reducing the critical nucleus size.", "B": "Apply external pressure. Pressure increases atomic packing density, creating more favorable nucleation sites.", "C": "Use slower cooling rates. Slow cooling allows more time for nuclei to form and stabilize.", "D": "Introduce dislocations. Dislocations act as preferential nucleation sites due to their strain fields." }, "correct_answer": "A", "explanation": "Correct answer A is right because increased undercooling directly lowers the nucleation barrier and increases nucleation rate. B is wrong because while pressure affects phase stability, it doesn't necessarily increase nucleation sites. C is a reversal trap - slower cooling actually decreases nucleation rate. D uses a plausible dislocation mechanism but in reality dislocations primarily affect growth kinetics rather than nucleation density.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 211, "question": "Many properties of clay are related to the types of adsorbed cations. Indicate the variation trend of the thixotropy of clay slurry when adsorbing the following different cations (use arrows to represent: small—large) H+ Al3+ Ba2+ Sr2+ Ca2+ Mg2+ NH4+ K+ Na+ Li+", "answer": "H+ < Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求用箭头表示不同阳离子对粘土浆触变性的影响趋势，答案是一个具体的排序结果，需要理解和解释不同阳离子的影响，属于简答题类型。 | 知识层次: 题目要求考生理解不同阳离子对粘土触变性的影响趋势，并能够根据离子电荷和半径等性质进行排序。这需要考生掌握粘土吸附阳离子的基本原理，并能将多个概念（离子性质、触变性）关联起来进行综合分析。虽然不涉及复杂计算，但需要对多个离子的影响进行比较和排序，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要掌握黏土吸附阳离子的规律及其对触变性的影响，涉及多个离子的比较和排序，要求考生具备较强的综合分析能力和对概念的理解深度。", "convertible": true, "correct_option": "H+ < Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+", "choice_question": "Many properties of clay are related to the types of adsorbed cations. Which of the following correctly represents the variation trend of the thixotropy of clay slurry when adsorbing the following different cations (use arrows to represent: small—large) H+ Al3+ Ba2+ Sr2+ Ca2+ Mg2+ NH4+ K+ Na+ Li+?", "conversion_reason": "The answer is a specific ordered sequence, which can be presented as one of multiple choice options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "H+ < Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+", "B": "Li+ < Na+ < K+ < NH4+ < H+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+", "C": "Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+ < H+", "D": "Na+ < Li+ < K+ < NH4+ < H+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+" }, "correct_answer": "A", "explanation": "The correct answer follows the Hofmeister series for cation effects on clay thixotropy, where thixotropic strength increases with cation charge and decreases with hydration radius. Option B incorrectly places H+ after monovalent cations due to underestimating its strong polarization effect. Option C reverses the entire trend, a common mistake when confusing thixotropy with dispersion stability. Option D misorders Li+/Na+ by overemphasizing ionic radius while neglecting hydration effects, a typical AI error in balancing multiple competing factors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 233, "question": "Compare the characteristics of the eutectic point in ternary invariant points and write its equilibrium relationship", "answer": "The eutectic point is a type of invariant point where several crystalline phases simultaneously precipitate from the melt upon cooling or melt together upon heating. The phase equilibrium relationship is L(E)⇄A+B+C", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较三元不变点中共晶点的特性并写出其平衡关系，需要文字解释和论述，答案也以文字形式给出解释和公式。 | 知识层次: 题目考查对共晶点特性的基本概念记忆和简单理解，涉及相平衡关系的基本原理，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（定义、分类、基本原理等），但需要考生理解并描述三元共晶点的特征及其平衡关系，而不仅仅是简单的定义复述。题目要求考生能够将共晶点的概念扩展到三元体系，并写出具体的相平衡关系式，这比单纯记忆定义需要更深一层的理解和应用。因此，在选择题型中属于等级2的难度。", "convertible": true, "correct_option": "The eutectic point is a type of invariant point where several crystalline phases simultaneously precipitate from the melt upon cooling or melt together upon heating. The phase equilibrium relationship is L(E)⇄A+B+C", "choice_question": "Which of the following correctly describes the eutectic point in ternary invariant points and its equilibrium relationship?", "conversion_reason": "The answer is a standard description of the eutectic point and its equilibrium relationship, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The eutectic point is a type of invariant point where several crystalline phases simultaneously precipitate from the melt upon cooling or melt together upon heating. The phase equilibrium relationship is L(E)⇄A+B+C", "B": "The eutectic point is a type of invariant point where a single crystalline phase transforms into another phase upon cooling. The phase equilibrium relationship is L(E)⇄A", "C": "The eutectic point is a type of invariant point where two crystalline phases form sequentially from the melt. The phase equilibrium relationship is L(E)⇄A+B followed by A⇄B+C", "D": "The eutectic point is a type of invariant point where the melt decomposes into a crystalline phase and a gas phase. The phase equilibrium relationship is L(E)⇄A+Gas" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately describes the eutectic point as an invariant point where multiple crystalline phases simultaneously form from or melt into the liquid phase. Option B is incorrect because it describes a simple phase transformation rather than a eutectic reaction. Option C is a cognitive bias trap, as it might seem plausible due to the sequential phase formation seen in some systems, but eutectic reactions are simultaneous. Option D is a professional intuition trap, playing on the misconception that invariant points must involve gas phases in some systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3554, "question": "In substitutional solid solutions, the general mode of atomic diffusion is (). \\n\\nA. Atomic exchange mechanism B. Interstitial mechanism C. Vacancy mechanism", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查的是对置换固溶体中原子扩散机制的基本概念记忆，属于基础概念的理解和记忆范畴。 | 难度: 在选择题型中，该题目属于基础概念记忆层次，考察的是对置换固溶体中原子扩散机制的基本理解。虽然需要区分三种不同的扩散机制（交换机制、间隙机制和空位机制），但题目直接给出了正确选项，且知识点相对明确，属于概念理解和简单辨析的难度级别。不需要复杂的分析或深度推理，只需掌握相关定义即可正确作答。", "convertible": true, "correct_option": "C. Vacancy mechanism", "choice_question": "In substitutional solid solutions, the general mode of atomic diffusion is ().", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Atomic exchange mechanism", "B": "Interstitial mechanism", "C": "Vacancy mechanism", "D": "Interstitialcy mechanism" }, "correct_answer": "C", "explanation": "The correct answer is C because in substitutional solid solutions, atoms diffuse primarily through vacancy mechanisms where atoms move into adjacent vacant lattice sites. Option A is a strong distractor as it appeals to the intuitive but incorrect idea of direct atom swapping. Option B exploits confusion with interstitial diffusion which occurs in different systems. Option D introduces a sophisticated but irrelevant mechanism to challenge advanced knowledge recall.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 397, "question": "What is the driving force for grain boundary migration?", "answer": "The driving forces for grain boundary migration are: the stored energy of deformation and the chemical potential difference across the grain boundary caused by grain boundary curvature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述晶界迁移的驱动力，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对晶界迁移驱动力的基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目要求考生理解并记忆晶界迁移的驱动力，包括变形储存能和晶界曲率引起的化学势差。虽然涉及两个概念，但都属于基础概念记忆范畴，不需要复杂的分析或比较。因此，难度属于中等偏下，对应等级2。", "convertible": true, "correct_option": "The stored energy of deformation and the chemical potential difference across the grain boundary caused by grain boundary curvature.", "choice_question": "What are the driving forces for grain boundary migration?", "conversion_reason": "The answer is a standard and concise explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The stored energy of deformation and the chemical potential difference across the grain boundary caused by grain boundary curvature", "B": "The difference in elastic modulus between adjacent grains and the surface energy anisotropy", "C": "The applied external stress and the temperature gradient across the grain boundary", "D": "The dislocation density difference and the lattice parameter mismatch between grains" }, "correct_answer": "A", "explanation": "The correct answer is A because grain boundary migration is primarily driven by the stored energy from deformation (providing the energy for boundary movement) and the curvature-induced chemical potential difference (creating a thermodynamic driving force). Option B is a cognitive bias trap, combining real but irrelevant material properties (elastic modulus and surface energy anisotropy). Option C exploits intuition by using plausible-sounding external factors (stress and temperature gradient) that don't directly drive boundary migration. Option D is a multi-level verification trap, mixing real microstructural features (dislocations and lattice mismatch) that affect grain boundary energy but aren't the primary migration drivers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 192, "question": "If a small bubble with a radius of $10^{-8}\\\\mathrm{m}$ is generated in water at $100^{\\\\circ}\\\\mathrm{C}$ and 101325Pa, can this small bubble exist and grow? The density of water at this time is $958\\\\mathrm{kg}/\\\\mathrm{m}^{3}$, and the surface tension is $0.0589\\\\mathrm{N/m}$.", "answer": "According to the formula $\\\\Delta P={\\\\frac{2\\\\gamma}{\\\\Delta}}$, the additional pressure can be calculated as $\\\\triangle P{=}2\\\\times0.0589/10^{-8}{=}1.178\\\\times10^{7}\\\\mathrm{Pa}$. For a bubble in liquid, the pressure inside the bubble is $P=P_{0}{\\\\longrightarrow}\\\\triangle P{=}101325{-}1.178{\\\\times}10^{7}<0$. Therefore, this small bubble cannot exist.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要通过公式计算额外压力，并根据计算结果判断气泡是否能存在。答案展示了具体的计算过程和数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式（ΔP=2γ/r）的直接应用和简单计算，不需要多步推理或综合分析。虽然需要理解气泡存在的条件，但整体思维过程较为直接，属于简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目要求直接套用公式$\\\\Delta P={\\\\frac{2\\\\gamma}{\\\\Delta}}$进行计算，并理解气泡内外压力差的概念。虽然涉及基本物理概念的理解，但解题步骤相对简单，仅需一次公式应用和简单计算即可得出结论。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "This small bubble cannot exist.", "choice_question": "If a small bubble with a radius of $10^{-8}\\mathrm{m}$ is generated in water at $100^{\\circ}\\mathrm{C}$ and 101325Pa, can this small bubble exist and grow? The density of water at this time is $958\\mathrm{kg}/\\mathrm{m}^{3}$, and the surface tension is $0.0589\\mathrm{N/m}$.", "conversion_reason": "The original question is a calculation problem with a definitive answer that can be converted into a multiple-choice format. The correct option is derived from the conclusion of the calculation.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "This small bubble cannot exist", "B": "The bubble can exist but cannot grow due to surface tension", "C": "The bubble will grow rapidly due to thermal energy overcoming surface tension", "D": "The bubble can exist stably at this size due to balanced forces" }, "correct_answer": "A", "explanation": "The correct answer is A because at this extremely small radius (10^-8 m), the Laplace pressure (2γ/r ≈ 11.78 MPa) far exceeds the vapor pressure of water at 100°C (101325 Pa), making the bubble thermodynamically unstable. Option B is a cognitive bias trap, making surface tension seem like the sole limiting factor. Option C exploits thermal energy intuition but ignores the enormous pressure difference. Option D creates a false equilibrium scenario by suggesting force balance at an unstable condition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1671, "question": "The _ (5) of an atom or ion refers to the number of atoms directly adjacent to it in the crystal structure or the number of all hetero-ions combined with it.", "answer": "(5) Coordination number", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（coordination number）来完成句子，而不是从多个选项中选择、判断对错或进行数值计算。这符合简答题的特征，即需要提供具体的文字答案。 | 知识层次: 题目考查的是\"配位数\"这一基本概念的定义，属于晶体结构中最基础的概念记忆和理解范畴，不需要进行计算或综合分析。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需考生回忆并识别\"配位数\"的定义即可。题目直接给出了概念的关键描述，正确选项与题干描述高度匹配，无需复杂推理或跨概念分析。属于选择题中最简单的难度等级，主要测试学生对基础术语的记忆能力。", "convertible": true, "correct_option": "Coordination number", "choice_question": "The _ of an atom or ion refers to the number of atoms directly adjacent to it in the crystal structure or the number of all hetero-ions combined with it.", "conversion_reason": "简答题的答案是标准术语，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Coordination number", "B": "Valence electron count", "C": "Atomic packing factor", "D": "Nearest neighbor distance" }, "correct_answer": "A", "explanation": "The correct answer is 'Coordination number' because it specifically refers to the number of adjacent atoms or hetero-ions in a crystal structure. 'Valence electron count' (B) exploits cognitive bias by sounding related to atomic bonding but refers to outer shell electrons. 'Atomic packing factor' (C) is a professional intuition trap as it involves spatial arrangement but measures volume efficiency. 'Nearest neighbor distance' (D) is a multi-level verification trap that seems plausible but refers to spatial separation rather than count.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3204, "question": "How does increasing undercooling refine grains?", "answer": "Increasing the undercooling ΔT causes both N and Vg to increase, but the growth rate of N is greater than that of Vg. Therefore, the value of N/Vg increases, meaning z becomes larger.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释undercooling如何细化晶粒，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要解释增加过冷度如何细化晶粒，涉及成核率（N）和生长速率（Vg）的变化及其相对关系，要求综合运用成核与生长理论进行机理分析，思维过程较深入。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解过冷度（ΔT）对晶粒细化（N/Vg）的影响机制，还需要综合运用成核率（N）和生长速率（Vg）的动态关系进行推理分析。正确选项涉及多变量相互作用（N和Vg增速差异）的机理解释，且需要推导最终结论（z值变化），这显著超出了基础概念记忆或简单比较的认知层次，完全符合\"复杂现象全面分析\"的能力要求。", "convertible": true, "correct_option": "Increasing the undercooling ΔT causes both N and Vg to increase, but the growth rate of N is greater than that of Vg. Therefore, the value of N/Vg increases, meaning z becomes larger.", "choice_question": "How does increasing undercooling refine grains?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increasing undercooling raises the nucleation rate more than the growth velocity, leading to higher N/Vg ratio", "B": "Higher undercooling decreases atomic diffusion, restricting grain boundary mobility", "C": "Undercooling increases thermal gradient, promoting equiaxed grain formation", "D": "The Gibbs-Thomson effect becomes dominant at high undercooling, limiting grain growth" }, "correct_answer": "A", "explanation": "Correct answer A reflects the fundamental relationship where nucleation rate (N) increases exponentially with undercooling while growth velocity (Vg) increases linearly. Option B exploits the common misconception about diffusion-limited growth, while C falsely attributes refinement to thermal gradients rather than nucleation kinetics. Option D uses a real phenomenon (Gibbs-Thomson) but misapplies it to bulk solidification rather than nanoscale systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4157, "question": "Match the following material types with their light transmission characteristics: Single crystal electrical insulators - Opaque, Translucent, Transparent", "answer": "Single crystal electrical insulators are transparent.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求将材料类型与光传输特性进行匹配，属于从多个选项中选择正确答案的类型 | 知识层次: 题目考查对单晶电绝缘体光学特性的基本概念记忆，属于定义和分类层面的基础知识点。 | 难度: 在选择题型中，该题目仅要求考生记忆单晶电绝缘体的光传输特性（透明），属于基础概念的直接识别和记忆。题目不涉及复杂辨析或多概念比较，符合等级1的简单概念识别标准。", "convertible": true, "correct_option": "Transparent", "choice_question": "What is the light transmission characteristic of single crystal electrical insulators?", "conversion_reason": "The original question is already in a multiple-choice format, asking to match a material type with its light transmission characteristic. It can be directly converted to a single-choice question by presenting the options (Opaque, Translucent, Transparent) and identifying the correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Transparent", "B": "Translucent due to internal grain boundaries", "C": "Opaque due to free electron absorption", "D": "Wavelength-dependent transparency with IR opacity" }, "correct_answer": "A", "explanation": "Single crystal electrical insulators are transparent because their perfect crystalline structure lacks defects or free electrons that would scatter or absorb visible light. Option B exploits the common misconception that all crystalline materials have grain boundaries. Option C traps those who incorrectly associate electrical insulation with metallic opacity mechanisms. Option D introduces a plausible-sounding but incorrect specialization that doesn't apply to perfect single crystals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2882, "question": "Assuming we add Na2O with w(Na2O)=10% to SiO2, please calculate the ratio of oxygen to silicon.", "answer": "There are 90at% SiO2 and 10at% Na2O, so O:Si = (0.9×2 + 0.1) : 0.9 = 2.111. Since O:Si = 2.111 < 2.5, there is a good tendency for glass formation.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算氧与硅的比例），并应用了化学计量公式。答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目涉及基本公式应用和简单计算，仅需将给定的百分比转换为原子百分比并进行简单的比例计算，无需多步推理或综合分析。 | 难度: 在选择题中属于简单难度，题目涉及基本公式应用和简单计算，仅需理解氧硅比的概念并进行直接套用计算，无需复杂步骤或多公式组合。", "convertible": true, "correct_option": "2.111", "choice_question": "Assuming we add Na2O with w(Na2O)=10% to SiO2, what is the ratio of oxygen to silicon?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.111", "B": "2.000", "C": "2.222", "D": "2.333" }, "correct_answer": "A", "explanation": "The correct answer is A (2.111) because the calculation involves considering the weight percentage of Na2O (10%) and its contribution to the oxygen content in the SiO2 matrix. The ratio is derived from the molar ratios of oxygen to silicon after accounting for the added Na2O. Option B (2.000) is a trap for those who assume pure SiO2 without considering the Na2O addition. Option C (2.222) exploits a common miscalculation where the weight percentage is incorrectly converted to molar ratio. Option D (2.333) is designed to catch those who overestimate the oxygen contribution from Na2O by ignoring the stoichiometry of SiO2.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4829, "question": "Compute the electrical conductivity of a cylindrical silicon specimen 7.0mm (0.28 in.) diameter and 57mm (2.25 in.) in length in which a current of 0.25 A passes in an axial direction. A voltage of 24V is measured across two probes that are separated by 45mm (1.75 in.).", "answer": "12.2 (omega·m)^{-1}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的物理参数（直径、长度、电流、电压）进行计算，最终得出电导率的数值结果。解答过程需要应用欧姆定律和电导率计算公式，属于典型的计算题类型。答案以数值形式给出，进一步验证了这是计算题。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过给定的电流、电压和几何尺寸计算电导率，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算硅圆柱体的电导率，只需要应用基本的电导率公式（σ = (I × L) / (V × A)），其中所有需要的参数（电流、电压、长度和横截面积）都已直接给出或可以通过简单计算得出。解题步骤简单直接，无需多个公式组合或复杂分析，因此属于最简单的难度等级。", "convertible": true, "correct_option": "12.2 (omega·m)^{-1}", "choice_question": "Compute the electrical conductivity of a cylindrical silicon specimen 7.0mm (0.28 in.) diameter and 57mm (2.25 in.) in length in which a current of 0.25 A passes in an axial direction. A voltage of 24V is measured across two probes that are separated by 45mm (1.75 in.). The electrical conductivity is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "12.2 (Ω·m)^{-1}", "B": "24.4 (Ω·m)^{-1}", "C": "6.1 (Ω·cm)^{-1}", "D": "48.8 (Ω·cm)^{-1}" }, "correct_answer": "A", "explanation": "正确答案A通过正确应用电导率公式σ = (I × L)/(V × A)计算得出，其中使用正确的单位转换(7mm直径→横截面积)和45mm探针间距。干扰项B通过错误使用总长度57mm而非探针间距45mm进行计算，利用长度参数选择直觉陷阱。干扰项C和D故意混淆Ω·m和Ω·cm单位制，其中C是正确答案的一半(单位错误)，D是B选项的Ω·cm版本，利用单位制转换和数值翻倍的双重陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 6, "question": "A crystal plane has intercepts of 2a, 3b, and 6c on the X, y, and z axes respectively. Find the Miller indices of this crystal plane.", "answer": "h:k:1=2:3:6=3:2:1, the Miller indices of this crystal plane are (321).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（Miller指数的计算步骤）来求解晶面的Miller指数，答案是一个具体的数值结果（321），属于典型的计算题特征。 | 知识层次: 题目需要应用Miller指数的基本计算公式，通过给定的截距进行简单计算即可得到结果，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解Miller指数的基本概念和计算方法，但解题步骤相对直接，只需根据给定的截距应用公式进行简单计算即可得出答案。不需要复杂的推理或多步骤的公式组合，因此在选择题型内属于等级2难度。", "convertible": true, "correct_option": "(321)", "choice_question": "A crystal plane has intercepts of 2a, 3b, and 6c on the X, y, and z axes respectively. What are the Miller indices of this crystal plane?", "conversion_reason": "The answer is a specific set of Miller indices, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(321)", "B": "(632)", "C": "(123)", "D": "(111)" }, "correct_answer": "A", "explanation": "正确答案是A(321)，因为Miller指数的正确计算步骤是取截距倒数(1/2,1/3,1/6)，然后乘以最小公倍数6得到(3,2,1)。干扰项B(632)是直接使用原始截距的常见错误；C(123)是倒序排列的直觉陷阱；D(111)是忽略截距直接假设最简单平面的典型错误。这些干扰项利用了材料科学初学者在晶体学指数计算中最容易犯的三种典型错误类型。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1831, "question": "Glass has the following general properties: (14)", "answer": "The transformation process is reversible and gradual", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对玻璃的一般性质进行描述，答案是一个陈述句，需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查玻璃的一般性质，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅考察对玻璃一般特性的基础概念记忆，正确选项直接对应教材中的基本定义（玻璃转变过程的可逆性和渐进性特征）。选择题型中无需复杂推理或概念关联，只需识别并选择与记忆内容匹配的选项即可，属于最基础层级的认知要求。", "convertible": true, "correct_option": "The transformation process is reversible and gradual", "choice_question": "Which of the following describes the general properties of glass?", "conversion_reason": "The answer is a standard description that can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The transformation process is reversible and gradual", "B": "It exhibits a sharp melting point like crystalline materials", "C": "Its viscosity follows Arrhenius temperature dependence at all temperatures", "D": "The glass transition temperature is a material constant independent of cooling rate" }, "correct_answer": "A", "explanation": "The correct answer is A because glass transition is indeed a reversible and gradual process, characteristic of amorphous materials. Option B exploits the common confusion between glass and crystalline materials. Option C is a cognitive bias trap - while viscosity follows Arrhenius behavior at high temperatures, it deviates near Tg. Option D is a professional intuition trap - Tg actually depends on cooling rate, contrary to what might be assumed from equilibrium phase transitions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3216, "question": "Given: The critical nucleus size of aluminum r*=94.5 nm, atomic volume V0=1.66×10^-29 m^3. Calculate the number of atoms Nr* in a nucleus with radius r*.", "answer": "Nr* = (4/3 π r*^3) / V0 = (4/3 π × (94.5 × 10^-9)^3) / (1.66 × 10^-29) = 2.12 × 10^8", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过具体计算得出的数值结果 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即通过给定的临界核尺寸和原子体积计算核中的原子数量，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算，即使用球形体积公式除以原子体积来得到原子数量。解题步骤简单，无需组合多个公式或进行复杂的概念分析，属于最基础的直接计算类型。", "convertible": true, "correct_option": "2.12 × 10^8", "choice_question": "Given: The critical nucleus size of aluminum r*=94.5 nm, atomic volume V0=1.66×10^-29 m^3. Calculate the number of atoms Nr* in a nucleus with radius r*.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.12 × 10^8", "B": "1.06 × 10^8", "C": "4.24 × 10^8", "D": "3.18 × 10^8" }, "correct_answer": "A", "explanation": "The correct calculation involves using the formula for the volume of a sphere (4/3πr^3) divided by the atomic volume. Option B is half the correct value, exploiting the common error of forgetting to cube the radius. Option C is double the correct value, targeting those who might confuse diameter with radius. Option D is 1.5 times the correct value, designed to catch those who might incorrectly average values.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 586, "question": "Explain the term: divorced eutectic", "answer": "Divorced eutectic: In alloys with a eutectic reaction, if the composition is far from the eutectic point, the primary crystals are abundant while the eutectic is scarce. The phase in the eutectic that is the same as the primary crystals grows attached to the primary crystals, and the other phase in the eutectic appears separately distributed, causing the eutectic structure to lose its characteristic features.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释术语\"divorced eutectic\"，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对\"divorced eutectic\"这一术语的定义和基本特征的理解，属于基础概念的记忆和解释。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释\"divorced eutectic\"这一术语，但正确选项提供了较为详细的定义和形成机制描述，需要考生不仅记住基本定义，还要理解其形成条件和微观结构特征。这超出了简单的定义记忆（等级1），但尚未达到需要阐述复杂概念体系的程度（等级3）。", "convertible": true, "correct_option": "Divorced eutectic: In alloys with a eutectic reaction, if the composition is far from the eutectic point, the primary crystals are abundant while the eutectic is scarce. The phase in the eutectic that is the same as the primary crystals grows attached to the primary crystals, and the other phase in the eutectic appears separately distributed, causing the eutectic structure to lose its characteristic features.", "choice_question": "Which of the following best describes the term 'divorced eutectic'?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When one phase in the eutectic grows attached to primary crystals while the other appears separately, causing loss of characteristic eutectic structure", "B": "A phenomenon where eutectic phases completely separate into distinct layers due to gravitational segregation", "C": "The decomposition of eutectic structure into amorphous phases during rapid solidification", "D": "When eutectic phases undergo spinodal decomposition resulting in periodic concentration fluctuations" }, "correct_answer": "A", "explanation": "The correct answer describes the actual phenomenon where eutectic loses its characteristic structure due to preferential growth of one phase. Option B incorrectly suggests gravitational segregation which doesn't occur at microstructural level. Option C confuses divorced eutectic with amorphous formation during rapid cooling. Option D incorrectly associates the phenomenon with spinodal decomposition which is a different diffusion-driven process.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 437, "question": "Polymers with simple structure, high regularity, and good symmetry are not prone to crystallization.", "answer": "(×)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性（答案用×表示错误），符合判断题的特征 | 知识层次: 题目考查对聚合物结晶条件的基本概念记忆和理解，涉及结构简单性、规则性和对称性对结晶倾向的影响，属于基础概念层次。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆聚合物结晶的基本原理即可作答，无需深入理解或分析多个概念。题目结构简单，直接考察基础定义，因此属于最低难度等级。", "convertible": true, "correct_option": "(×)", "choice_question": "Polymers with simple structure, high regularity, and good symmetry are not prone to crystallization.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous polymers will transition to crystalline state when cooled below their glass transition temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement contains multiple subtle traps. First, the use of 'all' is problematic because some polymers are inherently non-crystallizable due to their molecular structure. Second, the glass transition temperature (Tg) is not directly related to crystallization - crystallization occurs at the melting temperature (Tm) for semi-crystalline polymers. Third, amorphous polymers by definition lack long-range order and don't crystallize. The statement confuses these fundamental concepts in polymer science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3045, "question": "Ceramic materials can be used as high-temperature materials and also as wear-resistant materials.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对陶瓷材料基本应用领域的记忆和理解，属于基础概念的记忆性知识 | 难度: 该题目属于基础概念正误判断题，仅需记忆陶瓷材料的基本应用领域（高温材料和耐磨材料），无需深入理解或分析多个概念。在选择题型中，这是最简单的难度等级，仅需识别陈述是否符合基础定义。", "convertible": true, "correct_option": "√", "choice_question": "Ceramic materials can be used as high-temperature materials and also as wear-resistant materials.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit excellent wear resistance under all operating conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics are wear-resistant, the statement contains two absolute inaccuracies: 1) Not ALL ceramics have excellent wear resistance (e.g., some porous ceramics have poor wear resistance) 2) Wear resistance depends on operating conditions (e.g., certain ceramics may degrade in corrosive environments). The absolute terms 'all' and 'under all conditions' make this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 466, "question": "Sorbite", "answer": "A product of medium-temperature pearlite transformation, composed of lamellar ferrite and cementite, with smaller interlamellar spacing and thinner layers.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Sorbite\"进行文字解释和论述，答案提供了详细的描述，符合简答题的特征 | 知识层次: 题目考查对Sorbite这一基本概念的记忆和理解，包括其组成和结构特征，属于基础概念记忆性知识。 | 难度: 该题目属于基础概念记忆层次，要求考生能够准确回忆并描述Sorbite的定义和组成。虽然需要记忆具体的材料科学术语（如lamellar ferrite和cementite）以及其结构特征（smaller interlamellar spacing and thinner layers），但不需要进行复杂的分析或比较。在选择题型中，这属于中等偏下的难度，主要考察对基本概念的掌握程度。", "convertible": true, "correct_option": "A product of medium-temperature pearlite transformation, composed of lamellar ferrite and cementite, with smaller interlamellar spacing and thinner layers.", "choice_question": "Which of the following best describes Sorbite?", "conversion_reason": "The answer is a standard definition or description of a term, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A product of medium-temperature pearlite transformation, composed of lamellar ferrite and cementite, with smaller interlamellar spacing and thinner layers", "B": "A high-temperature austenite decomposition product characterized by spheroidized cementite particles in a ferrite matrix", "C": "A metastable transition phase between pearlite and bainite with unique dislocation substructures", "D": "An ultra-fine pearlite variant formed under extreme quenching conditions with nanometer-scale lamellae" }, "correct_answer": "A", "explanation": "The correct answer is A because sorbite is specifically defined as a refined pearlite structure formed at medium temperatures with finer lamellar spacing. Option B describes spheroidite, exploiting confusion between lamellar and spheroidal structures. Option C creates a false transitional phase concept, appealing to intuitive but incorrect phase progression reasoning. Option D describes a hypothetical ultra-fine structure, tempting with plausible-sounding extreme conditions that don't match sorbite's actual formation parameters.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1159, "question": "Annealing", "answer": "Annealing: A heat treatment process in which a metal or its alloy is heated above the phase transition temperature, held for a period of time, and then cooled at a relatively slow rate to obtain a nearly equilibrium microstructure is called annealing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Annealing\"进行文字解释和论述，答案提供了详细的定义和过程描述，符合简答题的特征。 | 知识层次: 题目考查对退火这一基本热处理工艺的定义和基本原理的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"Annealing\"的基本定义，属于最基础的概念记忆层次。题目描述直接给出了完整的定义，没有涉及复杂的概念体系或需要分析比较的内容，因此属于选择题型中最简单的难度等级。", "convertible": true, "correct_option": "Annealing: A heat treatment process in which a metal or its alloy is heated above the phase transition temperature, held for a period of time, and then cooled at a relatively slow rate to obtain a nearly equilibrium microstructure is called annealing.", "choice_question": "下列关于Annealing的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Annealing: A heat treatment process in which a metal or its alloy is heated above the phase transition temperature, held for a period of time, and then cooled at a relatively slow rate to obtain a nearly equilibrium microstructure is called annealing.", "B": "Annealing is a rapid cooling process used to lock in dislocations and increase hardness, similar to quenching but with slower cooling rates.", "C": "The primary purpose of annealing is to increase yield strength by creating a heavily deformed microstructure through controlled plastic deformation.", "D": "Annealing refers specifically to the heat treatment of aluminum alloys at temperatures below 200°C to relieve stresses without affecting precipitation hardening." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines annealing as a slow cooling process to achieve equilibrium microstructure. Option B incorrectly describes annealing as a rapid cooling process (confusing it with quenching). Option C wrongly associates annealing with deformation strengthening (a cold working process). Option D creates a specific but incorrect limitation to aluminum alloys and low temperatures, exploiting the common association between aluminum and heat treatment.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 904, "question": "Briefly describe the changes in stored energy during the annealing process of deformed metals", "answer": "The stored energy is gradually released.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述变形金属退火过程中储存能的变化，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对退火过程中变形金属储存能变化的基本概念的理解和记忆，属于基础知识的直接应用，不需要复杂的分析或综合。 | 难度: 在选择题型中，该题目仅要求考生记忆并复述变形金属退火过程中储存能量的基本变化规律（\"逐渐释放\"），属于最基础的定义性知识回忆，无需解释或分析过程，符合等级1的简答要求。", "convertible": true, "correct_option": "The stored energy is gradually released.", "choice_question": "What happens to the stored energy during the annealing process of deformed metals?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The stored energy is gradually released through dislocation annihilation and grain boundary migration", "B": "The stored energy transforms into surface energy as new grains form", "C": "The stored energy converts to thermal energy and raises the system temperature", "D": "The stored energy remains constant but redistributes within the crystal structure" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual mechanisms of energy release during annealing. Option B is a cognitive bias trap, confusing energy transformation types. Option C exploits the common but incorrect intuition about energy conversion. Option D is a professional intuition trap, appealing to conservation misconceptions while ignoring actual microstructural changes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4915, "question": "For the following pair of materials, decide which has the larger thermal conductivity. Justify your choice. Fused silica; polycrystalline silica", "answer": "Polycrystalline silica will have a larger conductivity than fused silica because fused silica is noncrystalline and lattice vibrations are more effectively scattered in noncrystalline materials.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的导热性能并给出合理的解释，需要文字论述和解释，符合简答题的特征。 | 知识层次: 题目要求比较两种材料的导热性能，并解释原因。这需要理解晶体结构对热导率的影响，以及非晶态和多晶态材料在热传导机制上的差异。虽然涉及基础概念，但需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解非晶态和多晶态材料对热导率的影响机制，并进行比较分析。题目要求考生掌握晶格振动散射的基本原理，并能将其应用于具体材料系统的比较，这需要中等层次的概念关联和综合分析能力。", "convertible": true, "correct_option": "Polycrystalline silica", "choice_question": "Which of the following materials has the larger thermal conductivity?", "conversion_reason": "The original question asks to decide which material has the larger thermal conductivity and justify the choice. The answer provided is a clear choice between two options (Fused silica and Polycrystalline silica), making it suitable for conversion to a multiple-choice format. The justification can be used as a distractor or additional information in the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polycrystalline silica (thermal conductivity increases with grain boundary scattering)", "B": "Fused silica (amorphous structure allows more efficient phonon transport)", "C": "Both have identical thermal conductivity (same chemical composition dominates)", "D": "Cannot be determined (depends on impurity concentration in each sample)" }, "correct_answer": "A", "explanation": "Polycrystalline silica has higher thermal conductivity because grain boundaries actually enhance phonon transport in silica due to its unique vibrational modes, contrary to most materials where grain boundaries reduce conductivity. Option B exploits the common misconception that amorphous materials always have lower conductivity. Option C uses composition equivalence fallacy ignoring microstructure effects. Option D creates uncertainty by introducing an irrelevant variable (impurities) when the question is about intrinsic properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3265, "question": "As an economic measure, using pure lead instead of lead-tin alloy to make solder for brazing iron, how does the melting point of pure lead compare to that of lead-tin alloy?", "answer": "The melting point of pure lead is higher than that of Sn-Pb alloy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释纯铅和铅锡合金的熔点比较，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对纯铅和铅锡合金熔点差异的基本概念记忆，属于基础概念层次，无需复杂分析或推理。 | 难度: 该题目属于基础概念记忆类型，仅需回忆纯铅和铅锡合金的熔点比较这一基本事实。选择题型中正确选项直接给出了明确结论，无需复杂推理或概念间的关联分析，属于最基础的定义简答级别。", "convertible": true, "correct_option": "The melting point of pure lead is higher than that of Sn-Pb alloy.", "choice_question": "As an economic measure, using pure lead instead of lead-tin alloy to make solder for brazing iron, how does the melting point of pure lead compare to that of lead-tin alloy?", "conversion_reason": "The answer is a standard comparison statement that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The melting point of pure lead is higher than that of Sn-Pb alloy due to the eutectic effect", "B": "The melting point remains unchanged because both are lead-based systems", "C": "The melting point decreases due to elimination of tin's higher melting point influence", "D": "The melting point becomes range-bound rather than a single value" }, "correct_answer": "A", "explanation": "The correct answer is A because the lead-tin alloy forms a eutectic system with a melting point (183°C) lower than pure lead's melting point (327°C). Option B exploits the 'same base material' misconception. Option C reverses the actual thermodynamic behavior. Option D describes a general alloy characteristic but doesn't address the specific comparison.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 362, "question": "For an alloy that has solidified with microscopic non-equilibrium segregation, what measures can be taken to accelerate diffusion and homogenize the alloy?", "answer": "Heating and annealing, deformation followed by annealing, or increasing vacancy concentration through high-energy particle irradiation to enhance diffusion (though this is uneconomical and impractical).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述具体的措施来加速扩散和均匀化合金，答案提供了多种可能的解决方案并进行了简要说明，符合简答题的特征。 | 知识层次: 题目要求考生理解非平衡偏析的概念，并应用扩散和均匀化的基本原理来提出解决方案。需要综合考虑加热退火、变形退火和高能粒子辐照等多种方法，并分析其优缺点。这涉及多步骤的思考和对不同处理方法的比较，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅理解非平衡偏析的基本概念，还需要综合掌握多种材料处理方法的原理（加热退火、变形后退火、高能粒子辐照）及其对扩散过程的影响机制。正确选项涉及多个步骤的工艺组合（如变形+退火）以及非常规方法（辐照）的经济性考量，需要考生进行多角度分析和概念关联。相比单纯记忆性选择题，本题需要更深入的材料科学知识储备和工艺原理的综合应用能力，因此属于选择题型中的较高难度等级。", "convertible": true, "correct_option": "Heating and annealing, deformation followed by annealing, or increasing vacancy concentration through high-energy particle irradiation to enhance diffusion (though this is uneconomical and impractical).", "choice_question": "For an alloy that has solidified with microscopic non-equilibrium segregation, which of the following measures can be taken to accelerate diffusion and homogenize the alloy?", "conversion_reason": "The answer is a standard set of measures that can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Heating to just below the solvus temperature followed by slow cooling to minimize residual stresses", "B": "Rapid quenching to room temperature to freeze the microstructure then aging at intermediate temperature", "C": "Severe plastic deformation at cryogenic temperatures to create excess vacancies", "D": "Applying high-frequency ultrasonic vibration during isothermal annealing" }, "correct_answer": "A", "explanation": "Correct answer (A) utilizes sub-solvus annealing which allows diffusion without melting while slow cooling prevents new segregation. Distractors: (B) mimics precipitation hardening but would exacerbate segregation, (C) creates vacancies but cryogenic temperature inhibits diffusion, (D) uses real phenomenon (acoustic softening) but is ineffective for bulk homogenization. All distractors exploit common materials processing heuristics that fail in this specific context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1202, "question": "Why can screw dislocations only undergo glide motion?", "answer": "Because it does not have a fixed half-atom plane", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么螺型位错只能进行滑移运动，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目需要解释螺位错只能进行滑移运动的机理，涉及位错的基本性质、运动方式及其与晶体结构的关系。这要求对位错理论有较深入的理解，并能进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生理解并解释螺型位错只能进行滑移运动的机理，这需要深入掌握位错的基本概念和运动机制。正确选项涉及对位错结构中半原子面的理解，这属于复杂分析层次的知识点。此外，题目要求考生能够将抽象的理论知识与具体现象联系起来，进行推理分析，这在选择题型中属于较高层次的认知要求。因此，该题目在选择题型内应评为等级4难度。", "convertible": true, "correct_option": "Because it does not have a fixed half-atom plane", "choice_question": "Why can screw dislocations only undergo glide motion?", "conversion_reason": "The answer is a standard concept or terminology, which can be converted into a multiple-choice question format by providing the correct option and plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because it does not have a fixed half-atom plane", "B": "Because screw dislocations can only move along their Burgers vector direction", "C": "Because the stress field of screw dislocations prevents climb motion", "D": "Because screw dislocations lack the necessary vacancy diffusion pathways" }, "correct_answer": "A", "explanation": { "correct": "The correct answer is A because screw dislocations lack the fixed half-atom plane required for climb motion, which is essential for dislocation movement out of the glide plane.", "distractors": { "B": "This is misleading because while screw dislocations do move along their Burgers vector during glide, this doesn't explain why they can't climb. Edge dislocations also move along their Burgers vector during glide but can still climb.", "C": "This is a subtle trap - while screw dislocations do have a different stress field than edge dislocations, this isn't the fundamental reason they can't climb. The stress field affects climb kinetics but not the possibility of climb.", "D": "This exploits confusion between climb mechanisms and diffusion pathways. While vacancy diffusion is needed for climb, the inability of screw dislocations to climb is fundamentally due to their geometry, not diffusion limitations." } }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2155, "question": "For a face-centered cubic crystal with a movable slip system of (111)[110], if the slip is caused by pure screw dislocations, indicate the direction of the dislocation line.", "answer": "The dislocation line lies on the slip plane and is parallel to b, so the direction of the dislocation line is [110].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案需要详细说明位错线的方向及其原因，而不是简单的选择或判断。 | 知识层次: 题目需要理解面心立方晶体滑移系统的基本概念，并能够将纯螺位错的性质与滑移方向关联起来。虽然涉及基础概念，但需要一定的综合分析能力来确定位错线的方向。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目要求考生理解面心立方晶体结构、滑移系统（111）[110]以及纯螺型位错的概念。其次，需要将位错线的方向与滑移方向（b矢量）联系起来，进行多步分析和概念关联。此外，题目还隐含了位错线必须位于滑移面上的条件，这需要考生具备综合分析能力。虽然题目给出了正确选项，但推导过程涉及多个晶体学概念的深度理解和应用，超出了简单记忆或单一概念应用的范畴，因此在选择题型中属于多角度分析论述的难度等级。", "convertible": true, "correct_option": "[110]", "choice_question": "For a face-centered cubic crystal with a movable slip system of (111)[110], if the slip is caused by pure screw dislocations, what is the direction of the dislocation line?", "conversion_reason": "The answer is a standard crystallographic direction, which can be presented as a clear option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[110]", "B": "[111]", "C": "[112]", "D": "[011]" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC crystals, the dislocation line direction for pure screw dislocations in the (111)[110] slip system is parallel to the Burgers vector [110]. Option B is a cognitive bias trap exploiting the common misconception that the dislocation line must align with the slip plane normal. Option C is a multi-level verification trap that seems plausible due to its relation to twinning directions in FCC. Option D is a professional intuition trap designed to catch those who confuse primary and secondary slip systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1874, "question": "When water-based substances melt into a liquid state, their volume undergoes the phenomenon of . A. expansion B. contraction C. no change", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项A、B、C中选择正确答案，符合选择题的特征 | 知识层次: 题目考查水基物质熔化时体积变化的基本现象记忆，属于基础概念的记忆和理解范畴 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即水基物质在融化时体积变化的现象。学生只需记住\"水基物质融化时体积收缩\"这一基本事实即可正确作答，无需进行概念辨析或深度理解。题目选项简单明确，属于直接记忆性知识，因此难度等级为1。", "convertible": true, "correct_option": "B", "choice_question": "When water-based substances melt into a liquid state, their volume undergoes the phenomenon of .", "conversion_reason": "The original question is already in a multiple-choice format, which can be directly used as a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The volume increases due to hydrogen bond breaking", "B": "The volume decreases as molecules pack more efficiently", "C": "The volume remains constant due to incompressibility of liquids", "D": "The volume change depends on the specific water-based substance" }, "correct_answer": "B", "explanation": "The correct answer is B because water-based substances typically contract upon melting due to the collapse of the open hydrogen-bonded network structure into a more densely packed liquid. Option A is a cognitive bias trap exploiting the common knowledge that hydrogen bonds break during melting, but ignoring the dominant effect of structural collapse. Option C uses a textbook statement about liquid incompressibility out of context. Option D is a professional intuition trap suggesting material-specific behavior when this is actually a universal phenomenon for water-based systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2023, "question": "A solid solution contains xMgO=30/10−2 and xLiF=70/10−2. What are the mass fractions of Li+, Mg2+, F−, and O2−?", "answer": "wLi+=16/10−2, wMg2+=24/10−2, wF−=44/10−2, wO2−=16/10−2", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算得出各离子的质量分数，需要应用化学计量和质量分数的计算公式，答案以具体数值形式给出。 | 知识层次: 题目涉及基本公式应用和简单计算，需要将摩尔分数转换为质量分数，属于直接套用公式的计算题，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用质量分数的基本公式，但计算步骤直接且无需复杂转换。题目提供了摩尔分数，只需简单转换为质量分数，属于选择题中较为基础的题型。", "convertible": true, "correct_option": "wLi+=16/10−2, wMg2+=24/10−2, wF−=44/10−2, wO2−=16/10−2", "choice_question": "A solid solution contains xMgO=30/10−2 and xLiF=70/10−2. What are the mass fractions of Li+, Mg2+, F−, and O2−?", "conversion_reason": "The question is a calculation problem with a definite answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "wLi+=16/10−2, wMg2+=24/10−2, wF−=44/10−2, wO2−=16/10−2", "B": "wLi+=14/10−2, wMg2+=28/10−2, wF−=42/10−2, wO2−=16/10−2", "C": "wLi+=18/10−2, wMg2+=22/10−2, wF−=46/10−2, wO2−=14/10−2", "D": "wLi+=16/10−2, wMg2+=24/10−2, wF−=42/10−2, wO2−=18/10−2" }, "correct_answer": "A", "explanation": "正确答案A正确计算了各离子的质量分数。干扰项B错误地将Mg2+的质量分数高估，利用了常见直觉错误。干扰项C故意在Li+和F−上增加数值，同时减少O2−，制造看似合理的分布。干扰项D在保持Li+和Mg2+正确的同时，微妙地调整了F−和O2−的比例，利用了计算过程中的常见疏忽。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1581, "question": "10. Habit plane", "answer": "During solid-state phase transformation, the new phase often forms along specific atomic planes of the parent phase. The parent phase crystal plane that is parallel to the main plane of the new phase is called the habit plane.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Habit plane\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查对“habit plane”这一基本概念的定义和解释，属于基础概念的记忆和理解范畴，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生理解并记忆\"habit plane\"的定义，即在新相形成过程中与母相特定原子平面对齐的晶体平面。虽然涉及固态相变的基本概念，但不需要复杂的分析或比较多个概念，只需准确描述定义即可。这符合等级2\"概念解释和描述\"的要求。", "convertible": true, "correct_option": "During solid-state phase transformation, the new phase often forms along specific atomic planes of the parent phase. The parent phase crystal plane that is parallel to the main plane of the new phase is called the habit plane.", "choice_question": "What is the definition of a habit plane in the context of solid-state phase transformation?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The parent phase crystal plane that is parallel to the main plane of the new phase during solid-state transformation", "B": "The plane with maximum atomic density where phase transformation initiates preferentially", "C": "The crystallographic plane exhibiting minimum interfacial energy between parent and product phases", "D": "The slip plane in the parent phase that facilitates martensitic transformation" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines the habit plane as the parent phase plane parallel to the main plane of the new phase. Option B is a cognitive bias trap, confusing habit plane with nucleation sites which often occur at high-density planes but aren't the definition. Option C is a professional intuition trap, as while interfacial energy is important, the habit plane isn't defined by energy minimization. Option D is a multi-level verification trap, mixing martensitic transformation mechanics with habit plane definition, as slip planes facilitate transformation but aren't the habit plane itself.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2286, "question": "A steel wire (with a diameter of $1~\\\\mathrm{mm}$) is coated with a layer of copper (total diameter of $2~\\\\mathrm{mm}$). What is the thermal expansion coefficient of this composite material? The elastic modulus of steel is $E_{\\\\mathrm{st}}{=}205~\\\\mathrm{GPa}$, and that of copper is $E_{\\\\mathrm{cu}}{=}110~\\\\mathrm{GPa}$; their expansion coefficients are $\\\\alpha_{\\\\mathrm{st}}=1.1\\\\times10^{-6}/\\\\mathsf{\\\\Pi}^{\\\\circ}\\\\mathsf{C}, \\\\alpha_{\\\\mathrm{Cu}}=17\\\\times10^{-6}/\\\\mathsf{\\\\Pi}^{\\\\circ}\\\\mathsf{C}$ respectively.", "answer": "Under no-load conditions, the composite material satisfies $(\\\\Delta l/L)_{\\\\mathrm{st}}=(\\\\Delta l/L)_{\\\\mathrm{cu}}$, and the forces $F_{\\\\mathrm{Cu}}=-F_{\\\\mathrm{st}}$. If $\\\\Delta t= 1^{\\\\circ}\\\\mathrm{C}$, then $$ A_{\\\\mathrm{Cu}}=\\\\pi(\\\\frac{d}{2})^{2}=(\\\\pi/4)(0.002\\\\mathrm{m})^{2}-0.8\\\\times10^{-6}\\\\mathrm{m}^{2}=2.4\\\\times10^{-6}\\\\mathrm{m}^{2}$$ $$ (\\\\Delta l/L)_{\\\\mathrm{st}}=(\\\\Delta l/L)_{\\\\mathrm{cu}}$$ $$ \\\\begin{array}{r}{\\\\left[\\\\alpha\\\\Delta t+(F/A)/E\\\\right]_{\\\\ast}=\\\\left[\\\\alpha\\\\Delta t+(F/A)/E\\\\right]_{\\\\mathrm{cu}}}\\\\end{array}$$ $$ 1\\\\times10^{-6})\\\\times1+{\\\\frac{F_{\\\\mathrm{st}}/(0.8\\\\times10^{-6}{\\\\mathrm{m}}^{2})}{205\\\\times10^{9}{\\\\mathrm{N/m}}^{2}}}=(17\\\\times10^{-6})\\\\times1+{\\\\frac{-F_{\\\\mathrm{st}}/(2.4\\\\times10^{-6}{\\\\mathrm{m}}^{2})}{110\\\\times10^{9}{\\\\mathrm{N/m}}^{2}}}$$ When $\\\\Delta t=1~^{\\\\circ}C$, then $$ (\\\\Delta l/L)_{\\\\mathrm{cu}}=(17\\\\times10^{-6}/^{9}\\\\mathbb{C}\\\\times1^{9}\\\\mathbb{C})+\\\\frac{=0.61~\\\\mathrm{N}/(2.4\\\\times10^{-6}~\\\\mathrm{m}^{2})}{110\\\\times10^{9}~\\\\mathrm{N/m}^{2}}=15\\\\times10^{-6}$$ Thus, the thermal expansion coefficient of the composite material is $$ \\\\overline{{\\\\alpha}}=15\\\\times10^{-6}/^{\\\\circ}\\\\mathrm{C}$$ $A_{\\\\mathrm{st}}=\\\\pi(\\\\frac{d}{2})^{2}=(\\\\pi/4)(0.001~\\\\mathrm{m})^{2}=0.8\\\\times10^{-6}~\\\\mathrm{m}^{2}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及热膨胀系数的复合计算，答案给出了具体的计算过程和结果。 | 知识层次: 题目涉及多步计算和概念关联，需要综合运用热膨胀系数、弹性模量等知识，并进行综合分析。虽然不涉及复杂的推理分析或机理解释，但需要理解和应用多个物理概念和公式，属于中等应用层次。 | 难度: 在选择题中属于高难度，题目涉及多步复杂计算和多个物理概念的关联应用。需要正确理解复合材料的膨胀行为，建立力学平衡方程，并进行精确的数值计算。解题步骤包括面积计算、应变平衡方程建立、力平衡条件应用以及最终的热膨胀系数求解，涉及多个变量和单位转换，对综合分析和计算能力要求较高。", "convertible": true, "correct_option": "15×10⁻⁶/°C", "choice_question": "A steel wire (with a diameter of 1 mm) is coated with a layer of copper (total diameter of 2 mm). What is the thermal expansion coefficient of this composite material? The elastic modulus of steel is E_st=205 GPa, and that of copper is E_cu=110 GPa; their expansion coefficients are α_st=1.1×10⁻⁶/°C, α_Cu=17×10⁻⁶/°C respectively.", "conversion_reason": "The problem involves a calculation with a definitive numerical answer, making it suitable for conversion into a multiple-choice question format where the correct answer is a specific value.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "15×10⁻⁶/°C", "B": "9.1×10⁻⁶/°C (体积平均法计算值)", "C": "17×10⁻⁶/°C (仅考虑铜层)", "D": "1.1×10⁻⁶/°C (仅考虑钢芯)" }, "correct_answer": "A", "explanation": "正确答案A是通过复合材料热膨胀系数计算公式得出的精确解，考虑了两种材料的弹性模量和截面积比。B选项利用体积平均法计算，忽略了弹性约束效应，是典型的第一印象陷阱。C选项仅考虑铜层，利用了材料科学中常见的'涂层主导效应'直觉陷阱。D选项仅考虑钢芯，利用了'基体主导'的错误直觉。这些干扰项都利用了AI模型可能存在的材料参数权重分配偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1511, "question": "Compared with pure iron, how do the strength and hardness of ferrite change", "answer": "Higher", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和比较纯铁和铁素体的强度和硬度变化，答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目考查对纯铁和铁素体强度与硬度变化的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即对纯铁和铁素体的强度与硬度进行比较。题目仅要求选择正确选项\"Higher\"，无需复杂的分析或推理步骤。属于最基本的概念记忆类题目，符合等级1的标准。", "convertible": true, "correct_option": "Higher", "choice_question": "Compared with pure iron, how do the strength and hardness of ferrite change?", "conversion_reason": "The answer is a standard term that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Higher", "B": "Lower", "C": "Same as pure iron", "D": "Depends on carbon content" }, "correct_answer": "A", "explanation": "Ferrite, being a solid solution of carbon in iron, exhibits higher strength and hardness compared to pure iron due to solid solution strengthening. Option B exploits the common misconception that pure elements are always stronger than their alloys. Option C creates confusion by suggesting no change in properties. Option D introduces a partially correct but irrelevant factor (carbon content affects pearlite vs ferrite ratio, not the intrinsic hardness comparison).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4581, "question": "Germanium to which 5 × 10^22 m^-3 Sb atoms have been added is an extrinsic semiconductor at room temperature, and virtually all the Sb atoms may be thought of as being ionized (i.e., one charge carrier exists for each Sb atom). Is this material n-type or p-type?", "answer": "this germanium material to which has been added 5 × 10^22 m^-3 sb atoms is n-type since sb is a donor in ge.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释和论述来判断材料的类型（n-type或p-type），而不是从多个选项中选择、判断对错或进行数值计算。答案也以文字解释的形式给出。 | 知识层次: 题目考查对半导体掺杂类型的基本概念的理解，即施主掺杂（Sb）导致n型半导体。这属于基础概念的记忆和理解，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目仅需要考生记忆基本的半导体类型分类知识，即知道锑（Sb）在锗（Ge）中是施主杂质，因此掺杂后形成n型半导体。不需要进行复杂的分析或推理，属于最基础的定义记忆类题目。", "convertible": true, "correct_option": "n-type", "choice_question": "Germanium to which 5 × 10^22 m^-3 Sb atoms have been added is an extrinsic semiconductor at room temperature, and virtually all the Sb atoms may be thought of as being ionized (i.e., one charge carrier exists for each Sb atom). Is this material:", "conversion_reason": "The answer is a standard term (n-type or p-type) which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "n-type due to Sb acting as a donor impurity", "B": "p-type due to Ge vacancies created during doping", "C": "n-type but with minority carriers dominating conduction", "D": "p-type due to Sb atoms forming acceptor levels" }, "correct_answer": "A", "explanation": "The correct answer is A because Sb is a Group V element that donates electrons to the Ge lattice, creating n-type conductivity. Option B exploits the common misconception that doping always creates vacancies. Option C reverses the carrier dominance logic to trap models expecting minority carrier effects. Option D deliberately misrepresents Sb's donor nature as acceptor behavior, playing on elemental property confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1723, "question": "Summarize the grain boundary strengthening mechanism in the application of dislocation theory in materials science, considering the factors affecting the strength of metal materials", "answer": "Grain boundary strengthening, according to the Hall-Petch formula, essentially means that additional stress is required for dislocations to cross grain boundaries.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对晶界强化机制进行总结，并考虑影响金属材料强度的因素，需要文字解释和论述，而不是选择、判断或计算。答案也提供了简要的解释，符合简答题的特征。 | 知识层次: 题目要求总结晶界强化机制，并应用位错理论进行解释，同时考虑影响金属材料强度的因素。这需要综合运用多个概念（晶界、位错、Hall-Petch关系等），进行机理层面的分析和解释，涉及较高层次的认知能力和思维深度。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Grain boundary strengthening, according to the Hall-Petch formula, essentially means that additional stress is required for dislocations to cross grain boundaries.", "choice_question": "Which of the following best summarizes the grain boundary strengthening mechanism in the application of dislocation theory in materials science, considering the factors affecting the strength of metal materials?", "conversion_reason": "The answer is a standard concept in materials science and can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain boundary strengthening, according to the Hall-Petch formula, essentially means that additional stress is required for dislocations to cross grain boundaries.", "B": "Grain boundary strengthening primarily increases material strength by reducing the elastic modulus at the grain boundaries.", "C": "The strengthening effect is due to grain boundaries acting as perfect sinks for dislocations, eliminating their movement entirely.", "D": "Grain size refinement strengthens materials by increasing the number of slip systems available for dislocation motion." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the Hall-Petch relationship where grain boundaries act as barriers to dislocation motion, requiring additional stress. Option B incorrectly associates strengthening with elastic modulus reduction, which is unrelated. Option C overstates the effect by claiming complete dislocation elimination. Option D reverses the mechanism by suggesting increased slip systems rather than constrained dislocation movement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3422, "question": "Explain the meaning of the steel grade GCr15SiMn", "answer": "GCr15SiMn is a rolling bearing steel, wc=1.5%, Wc=1%, wsi=0.5%, WM=1.05%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释GCr15SiMn钢的含义，答案提供了详细的成分说明和文字解释，符合简答题的特征。 | 知识层次: 题目考查对特定钢号（GCr15SiMn）的基本成分和分类的记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释钢号GCr15SiMn的含义，但正确选项已经提供了具体的化学成分和用途（滚动轴承钢），这需要考生对钢号命名规则和基本合金元素的作用有一定的记忆和理解。题目涉及的知识点属于基础概念记忆，但需要考生能够将钢号中的字母和数字与具体的化学成分对应起来，并理解其用途，因此比单纯的定义记忆题稍复杂。", "convertible": true, "correct_option": "GCr15SiMn is a rolling bearing steel, wc=1.5%, Wc=1%, wsi=0.5%, WM=1.05%", "choice_question": "Which of the following correctly describes the steel grade GCr15SiMn?", "conversion_reason": "The answer is a standard description of the steel grade, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "GCr15SiMn is a rolling bearing steel, wc=1.5%, Wc=1%, wsi=0.5%, WM=1.05%", "B": "GCr15SiMn is a tool steel with high carbon content (1.5%C) and 15% Cr for corrosion resistance", "C": "GCr15SiMn is a spring steel containing 15% Cr and 1% Si for improved elasticity", "D": "GCr15SiMn is a stainless steel with 15% Cr and Mn added for austenite stabilization" }, "correct_answer": "A", "explanation": "The correct answer is A because GCr15SiMn is specifically a rolling bearing steel with precise alloying element contents: 1.5% Cr (not 15%), 1% C, 0.5% Si, and 1.05% Mn. Option B is a cognitive bias trap - it incorrectly interprets '15' as 15% Cr and misclassifies it as tool steel. Option C exploits spring steel intuition by mentioning elasticity, but wrongly assumes 15% Cr content. Option D is a stainless steel analogy trap, incorrectly applying austenite stabilization logic to a bearing steel.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1519, "question": "For a screw dislocation line, its Burgers vector is _（20） to the dislocation line", "answer": "（20） parallel", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（parallel）来补全句子，而不是从多个选项中选择或进行判断/计算。虽然形式上类似填空题，但更符合简答题中需要特定知识回答的特征。 | 知识层次: 题目考查对螺位错基本概念的记忆和理解，即螺位错的柏氏矢量与位错线的关系，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念记忆类型，仅需考生记住螺位错的柏氏矢量与位错线的关系这一基本定义即可作答。在选择题型中，这种直接考查定义的题目属于最简单级别，不需要任何分析或推理过程。", "convertible": true, "correct_option": "parallel", "choice_question": "For a screw dislocation line, its Burgers vector is _ to the dislocation line", "conversion_reason": "The answer is a standard term (parallel) that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "parallel", "B": "perpendicular", "C": "at 45° angle", "D": "anti-parallel" }, "correct_answer": "A", "explanation": "The correct answer is A because for a screw dislocation, the Burgers vector is parallel to the dislocation line by definition. Option B is a common misconception from confusing screw with edge dislocations. Option C exploits the visual similarity to mixed dislocations. Option D creates cognitive conflict by introducing a physically possible but definitionally incorrect orientation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1932, "question": "Please explain what is a partial dislocation", "answer": "Partial dislocation: The Burgers vector is not an integer multiple of the lattice vector.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释部分位错的概念，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查的是对部分位错（partial dislocation）这一基本概念的定义记忆和理解，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，该题目仅要求对\"partial dislocation\"的基本定义进行记忆性回答，属于最基础的概念识别层面。正确选项直接给出了教科书式的定义，无需任何解释或推理步骤，完全符合\"基础概念记忆\"的知识层次要求。", "convertible": true, "correct_option": "The Burgers vector is not an integer multiple of the lattice vector.", "choice_question": "Which of the following correctly describes a partial dislocation?", "conversion_reason": "The answer is a standard definition that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Burgers vector is not an integer multiple of the lattice vector", "B": "It involves only edge dislocations without screw components", "C": "The dislocation line terminates inside the crystal lattice", "D": "It occurs exclusively in FCC metals with stacking faults" }, "correct_answer": "A", "explanation": "The correct answer is A because partial dislocations are characterized by Burgers vectors that are fractions of the lattice vector. Option B is incorrect as it falsely limits partial dislocations to edge types. Option C describes a general dislocation feature, not specific to partial dislocations. Option D is a common misconception, as partial dislocations can occur in various crystal structures, not just FCC metals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2216, "question": "To refine the grain of a pure aluminum part, it was cold deformed by 5% and then annealed at 650°C for 1 hour, but the structure coarsened instead. Analyze the reason for this.", "answer": "Since the deformation of the aluminum part was under the critical deformation degree, only a few recrystallization nuclei could form during annealing, resulting in extremely coarse grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析原因并进行文字解释和论述，答案也是以文字形式给出解释，没有涉及选择、判断或计算。 | 知识层次: 题目要求分析纯铝零件在冷变形和退火后晶粒粗化的原因，涉及临界变形度、再结晶成核和晶粒长大等复杂机理的综合推理和解释。需要深入理解材料加工过程中的微观结构演变，并能够将多个概念关联起来进行综合分析。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Since the deformation of the aluminum part was under the critical deformation degree, only a few recrystallization nuclei could form during annealing, resulting in extremely coarse grains.", "choice_question": "To refine the grain of a pure aluminum part, it was cold deformed by 5% and then annealed at 650°C for 1 hour, but the structure coarsened instead. What is the reason for this?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The 5% deformation was below the critical strain for recrystallization, leading to abnormal grain growth", "B": "The annealing temperature exceeded the melting point of pure aluminum, causing partial melting", "C": "Cold deformation introduced impurities that accelerated grain boundary migration", "D": "The 1-hour annealing time was insufficient for complete recrystallization" }, "correct_answer": "A", "explanation": "The correct answer is A because 5% deformation is below the typical critical strain (2-10%) required for normal recrystallization in pure aluminum, leading to abnormal grain growth. B is incorrect as 650°C is below aluminum's melting point (660°C). C is a plausible-sounding but incorrect explanation as pure aluminum wouldn't have such impurity effects. D is misleading because while time affects grain size, the primary issue here is insufficient deformation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2469, "question": "For a silicon-containing low-alloy steel ingot with dendritic segregation and a dendrite arm spacing of 500μm, diffusion annealing is performed at 1200°C. To reduce the segregation amplitude to 10% of its original value, how long should the holding time be for carbon? Given that the diffusion coefficient of carbon in austenite at 1200°C is 2.23×10^(-6)cm^2/s.", "answer": "When dendritic segregation exists, the solute composition is distributed with the dendrite arm spacing as the period, where the period l is 500μm=0.05cm. According to the trigonometric series solution of the diffusion equation, the concentration amplitude decays with a decay factor, i.e., C=C¯+C0sin(πx/l)exp(-π^2Dt/l^2). If the amplitude decays to 1/10 of its original value, then exp(-π^2Dt/l^2)=0.1. Therefore, the required time for carbon is: t=l^2/(π^2D)ln0.1=-(0.025)^2/(π^2×2.23×10^(-6))ln0.1s=65.3s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解所需的保温时间，答案中包含了具体的计算步骤和最终数值结果。 | 知识层次: 题目需要进行多步计算，包括理解扩散方程的三角级数解、应用衰减因子公式、以及对数运算。虽然涉及的知识点较为明确，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程的解法和浓度振幅衰减的概念，并进行多步计算。题目涉及三角函数解、指数衰减和时间计算，需要综合分析多个知识点才能得出正确答案。虽然计算步骤明确，但概念关联和公式应用要求较高，属于综合性计算问题。", "convertible": true, "correct_option": "65.3s", "choice_question": "For a silicon-containing low-alloy steel ingot with dendritic segregation and a dendrite arm spacing of 500μm, diffusion annealing is performed at 1200°C. To reduce the segregation amplitude to 10% of its original value, how long should the holding time be for carbon? Given that the diffusion coefficient of carbon in austenite at 1200°C is 2.23×10^(-6)cm^2/s.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "65.3s", "B": "32.7s", "C": "130.6s", "D": "16.3s" }, "correct_answer": "A", "explanation": "正确答案A是通过扩散方程计算得出的精确结果。干扰项B设计为正确答案的一半，利用AI可能忽略平方关系的直觉陷阱；干扰项C是正确答案的两倍，针对可能错误理解衰减比例的AI；干扰项D是正确答案的四分之一，针对可能混淆扩散距离与时间关系的AI。这些干扰项都利用了材料科学中扩散问题的常见计算误区。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2000, "question": "The atomic radius is related to the crystal structure. How does the atomic radius change when the coordination number of the crystal structure decreases?", "answer": "The atomic radius contracts. This is because the atom tries to maintain the volume it occupies as unchanged or with minimal change [the volume occupied by the atom $V_{A}=$ the volume of the atom () + the interstitial volume]. When the coordination number of the crystal structure decreases, the interstitial volume increases. To maintain the balance of the above equation, the atomic radius must contract.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释原子半径如何随配位数变化，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目不仅需要理解原子半径和配位数之间的关系，还需要解释原子半径收缩的机理，涉及体积守恒的概念和平衡方程的维持，需要综合运用多个概念进行推理分析。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解原子半径与晶体结构的关系，还需要深入掌握配位数变化对原子半径影响的机理。正确选项涉及复杂的体积守恒原理和间隙体积概念，需要考生进行多步推理分析（从配位数变化→间隙体积变化→原子半径补偿性收缩）。这种在选择题中要求综合运用多个高阶概念并解释深层机理的题目，远超出基础记忆或简单应用层面，属于复杂现象全面分析的难度范畴。", "convertible": true, "correct_option": "The atomic radius contracts.", "choice_question": "How does the atomic radius change when the coordination number of the crystal structure decreases?", "conversion_reason": "The answer is a standard and concise statement that can be directly used as a correct option in a multiple-choice question. The question itself is already in a form that can be adapted to a multiple-choice format without significant changes.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The atomic radius contracts due to reduced electron shielding", "B": "The atomic radius expands as interatomic forces weaken", "C": "No change occurs because atomic radius is an intrinsic property", "D": "The atomic radius first expands then contracts through a phase transition" }, "correct_answer": "A", "explanation": "The correct answer is A because decreasing coordination number reduces electron delocalization, leading to stronger effective nuclear charge and atomic contraction. Option B exploits the common misconception that reduced coordination automatically weakens bonding. Option C traps those who confuse atomic radius with ionic radius. Option D mimics real but irrelevant phase transition behaviors to mislead.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1142, "question": "What is the slip plane of face-centered cubic metals?", "answer": "{111}", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答具体的晶面指数{111}，属于需要特定知识点的简短回答，不需要计算或选择过程 | 知识层次: 题目考查面心立方金属滑移面的基本概念记忆，属于材料科学晶体结构的基础知识点，仅需直接回忆或理解{111}晶面族是FCC金属的滑移面这一事实即可回答。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别面心立方金属的滑移面{111}，属于基础概念记忆层次。题目不涉及概念解释或复杂体系阐述，仅需直接回忆定义性知识，因此属于最简单的难度等级1。", "convertible": true, "correct_option": "{111}", "choice_question": "What is the slip plane of face-centered cubic metals?", "conversion_reason": "The answer is a standard term in materials science, making it suitable for conversion to a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "{111}", "B": "{110}", "C": "{100}", "D": "{112}" }, "correct_answer": "A", "explanation": "The correct slip plane for FCC metals is {111} because it has the highest atomic packing density and lowest energy barrier for dislocation motion. Option B {110} is the slip plane for BCC metals, exploiting cognitive bias from common metallurgy knowledge. Option C {100} appears plausible due to its high symmetry but has lower atomic density. Option D {112} is a real FCC twinning plane, creating a multi-level verification trap by mixing slip and twinning concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4834, "question": "Briefly state what is meant by the drift velocity of a free electron.", "answer": "The drift velocity of a free electron is the average electron velocity in the direction of the force imposed by an electric field.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要解释自由电子的漂移速度的定义，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目考查对自由电子漂移速度这一基本概念的定义和简单理解，属于基础概念记忆范畴 | 难度: 在选择题型中，该题目仅要求考生记忆并复述自由电子漂移速度的基本定义，属于最基础的概念记忆层次。题目不涉及任何解释、分析或复杂概念的整合，解题步骤极为简单，仅需识别正确选项即可。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "The drift velocity of a free electron is the average electron velocity in the direction of the force imposed by an electric field.", "choice_question": "Which of the following best describes the drift velocity of a free electron?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The drift velocity of a free electron is the average electron velocity in the direction of the force imposed by an electric field", "B": "The drift velocity of a free electron is the instantaneous maximum velocity achieved during electron scattering events", "C": "The drift velocity of a free electron is equal to the Fermi velocity of electrons in the material", "D": "The drift velocity of a free electron represents the actual speed of electron movement through the crystal lattice" }, "correct_answer": "A", "explanation": { "correct_answer": "This is the precise definition of drift velocity, accounting for both the random thermal motion and net directional movement under electric field", "distractors": { "B": "Taps into the common confusion between average velocity and instantaneous values, exploiting AI's tendency to focus on extreme events", "C": "Leverages the cognitive bias of equating important material parameters (Fermi velocity) with transport properties", "D": "Exploits the intuitive but incorrect assumption that electrons move smoothly through the lattice rather than undergoing scattering" } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3159, "question": "What type of alloy phase does CuZn belong to, and what are its structural characteristics?", "answer": "CuZn is an electron compound, c13=3.12, with a body-centered cubic structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释CuZn合金相的类型及其结构特征，答案提供了详细的文字描述和结构特点，符合简答题的特征。 | 知识层次: 题目考查合金相的基本分类和结构特征的记忆，属于基础概念的记忆和理解层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及合金相的类型和结构特征，但正确选项直接提供了CuZn的电子化合物类型、c13值和体心立方结构，这些信息属于基础概念记忆范畴。考生需要掌握电子化合物的定义和体心立方结构的基本特征，但不需要进行复杂的分析或推理。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "CuZn is an electron compound, c13=3.12, with a body-centered cubic structure.", "choice_question": "Which of the following correctly describes the alloy phase and structural characteristics of CuZn?", "conversion_reason": "The answer is a standard description of the alloy phase and structural characteristics, which can be converted into a multiple-choice format by presenting it as the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "CuZn is an electron compound, c/a=3.12, with a body-centered cubic structure", "B": "CuZn is an interstitial compound with a hexagonal close-packed structure and c/a=1.633", "C": "CuZn is a substitutional alloy with face-centered cubic structure and lattice parameter 0.361 nm", "D": "CuZn is an intermetallic compound with CsCl-type structure and electron concentration 3/2" }, "correct_answer": "A", "explanation": "The correct answer is A because CuZn (β-brass) is indeed an electron compound with a body-centered cubic structure and c/a ratio of 3.12 at room temperature. Option B is wrong but tempting because it uses the correct c/a terminology but applies it to the wrong structure type (HCP). Option C exploits the common knowledge that pure Cu is FCC, creating a substitutional alloy misconception. Option D uses accurate terminology (intermetallic, CsCl-type) but gives wrong electron concentration (should be 21/14=3/2 is incorrect for β-brass).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 401, "question": "Explain the conditions for spinodal decomposition.", "answer": "Conditions for spinodal decomposition: In a binary alloy phase diagram with a miscibility gap, the composition free energy curve has a range where ∂²G/∂x²<0, the temperature is sufficiently high for solute atoms to diffuse. (The decrease in free energy must be sufficient to overcome gradient energy and strain energy. This point is not required to be answered and will not be penalized.)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释spinodal decomposition的条件，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释spinodal分解的条件，涉及对二元合金相图和自由能曲线的理解，需要将多个概念（如miscibility gap、自由能二阶导数、扩散条件等）关联起来进行综合分析。虽然不涉及复杂计算，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅要理解spinodal分解的基本概念，还需要掌握二元合金相图中混溶间隙的特征，以及自由能曲线二阶导数的物理意义。此外，题目还隐含了需要理解温度对扩散过程的影响。这些知识点需要考生进行多角度的分析和概念关联，超出了简单记忆的范畴，属于中等应用层次中较复杂的综合分析题。虽然题目给出了完整答案，但在选择题型中识别和判断这些条件的正确性仍需要较深入的理解。", "convertible": true, "correct_option": "In a binary alloy phase diagram with a miscibility gap, the composition free energy curve has a range where ∂²G/∂x²<0, the temperature is sufficiently high for solute atoms to diffuse.", "choice_question": "Which of the following describes the conditions for spinodal decomposition?", "conversion_reason": "The answer is a standard description of the conditions for spinodal decomposition, which can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In a binary alloy phase diagram with a miscibility gap, the composition free energy curve has a range where ∂²G/∂x²<0, the temperature is sufficiently high for solute atoms to diffuse.", "B": "When the alloy composition falls within the spinodal region and the temperature is below the critical point, leading to spontaneous phase separation without nucleation.", "C": "In any binary system where the free energy of mixing is positive, regardless of the temperature or diffusion conditions.", "D": "When the alloy is quenched rapidly from a high temperature to room temperature, creating a supersaturated solid solution that decomposes via spinodal mechanism." }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the thermodynamic (∂²G/∂x²<0) and kinetic (sufficient diffusion) conditions for spinodal decomposition. Option B is a cognitive bias trap - while partially correct, it incorrectly states the temperature must be below the critical point (actually needs to be within the spinodal region). Option C exploits professional intuition by suggesting any positive ΔGmix system can undergo spinodal decomposition, ignoring the crucial curvature requirement. Option D is a multi-level trap combining correct quenching concepts with incorrect application to spinodal decomposition, which doesn't require nucleation but does need specific thermodynamic conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3023, "question": "When a polymer material is subjected to force, the elasticity achieved by the movement of chain segments is (2). A. Ordinary elasticity B. High elasticity C. Viscoelasticity D. Forced elasticity", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对聚合物材料弹性类型的基本概念记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生理解聚合物材料在受力时的弹性类型，并能够区分普通弹性、高弹性、粘弹性和强制弹性等概念。这要求考生不仅记住定义，还要能够进行简单的概念辨析。", "convertible": true, "correct_option": "B", "choice_question": "When a polymer material is subjected to force, the elasticity achieved by the movement of chain segments is:", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The energy dissipation is primarily due to covalent bond stretching", "B": "The stress-strain curve shows perfect linearity up to 500% elongation", "C": "The elastic recovery occurs through reptation of entire polymer chains", "D": "The modulus remains constant regardless of strain rate or temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because polymer elasticity primarily involves secondary bond deformation, not covalent bond stretching. Option B is misleading as it suggests ideal Hookean behavior at large strains, which is impossible for real polymers. Option C incorrectly suggests reptation (a long-term relaxation mechanism) is responsible for elastic recovery. Option D violates fundamental viscoelastic principles by suggesting modulus independence from rate/temperature.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1386, "question": "What are the beneficial aspects of the work hardening characteristics of metals for the use of metal materials?", "answer": "As a means to improve the strength of metal materials; facilitating the plastic forming of metal materials; enabling metal parts to resist accidental overload.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释金属材料加工硬化特性的有益方面，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释金属加工硬化特性的有益方面，涉及对金属材料强度提升、塑性成形和抗过载能力的综合分析。虽然不需要复杂的计算或深度机理分析，但需要将多个概念关联起来进行解释，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解金属加工硬化的多个有益方面，包括提高强度、促进塑性成形和抵抗意外过载，并进行综合分析。虽然题目涉及多个概念，但在选择题型中，正确选项已经提供了明确的答案方向，不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "As a means to improve the strength of metal materials; facilitating the plastic forming of metal materials; enabling metal parts to resist accidental overload.", "choice_question": "What are the beneficial aspects of the work hardening characteristics of metals for the use of metal materials?", "conversion_reason": "The answer is a standard and concise explanation that can be directly used as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Enhancing fatigue resistance by preventing dislocation movement", "B": "Increasing electrical conductivity through grain refinement", "C": "Improving corrosion resistance by forming passive oxide layers", "D": "Reducing thermal expansion coefficient via strain hardening" }, "correct_answer": "A", "explanation": "Correct answer A is valid because work hardening impedes dislocation motion which can delay fatigue crack initiation. Option B exploits confusion between mechanical and electrical properties - grain refinement actually decreases conductivity. Option C misattributes corrosion resistance to work hardening instead of alloying elements. Option D creates a false correlation between strain hardening and thermal expansion which are fundamentally unrelated properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4451, "question": "The modulus of elasticity for boron carbide (B4C) having 5 vol% porosity is 290 GPa (42 x 10^6 psi). At what volume percent porosity will the modulus of elasticity be 235 GPa (34 x 10^6 psi)?", "answer": "the modulus of elasticity will be 235 GPa (34 x 10^6 psi) at a porosity of 15.1 vol%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解孔隙率，答案是一个具体的数值结果（15.1 vol%），而不是选择、判断或文字解释。 | 知识层次: 题目需要应用弹性模量与孔隙率之间的关系公式进行多步计算，涉及概念关联和综合分析，但不需要复杂的推理或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解弹性模量与孔隙率之间的关系，并应用相关公式进行多步计算。虽然题目提供了部分数据，但解题过程涉及综合分析和对概念的理解，需要一定的计算能力和材料科学知识。", "convertible": true, "correct_option": "15.1 vol%", "choice_question": "The modulus of elasticity for boron carbide (B4C) having 5 vol% porosity is 290 GPa (42 x 10^6 psi). At what volume percent porosity will the modulus of elasticity be 235 GPa (34 x 10^6 psi)?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "15.1 vol%", "B": "12.8 vol% (using linear extrapolation from 5% porosity)", "C": "17.3 vol% (assuming exponential decay model)", "D": "9.6 vol% (applying rule-of-mixtures inversely)" }, "correct_answer": "A", "explanation": "The correct answer uses the exponential porosity-dependence relationship for ceramic materials. Option B exploits the common mistake of linear extrapolation which doesn't account for the accelerating effect of porosity on modulus reduction. Option C uses a plausible but incorrect exponential model with wrong parameters. Option D reverses the rule-of-mixtures logic which is inappropriate for porosity effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4890, "question": "Cite several reasons why fiberglass-reinforced composites are used extensively.", "answer": "Reasons why fiberglass-reinforced composites are utilized extensively are: (1) glass fibers are very inexpensive to produce; (2) these composites have relatively high specific strengths; and (3) they are chemically inert in a wide variety of environments.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举并解释纤维增强复合材料广泛使用的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目主要考查对纤维增强复合材料应用原因的基础概念记忆和理解，答案列举的是该类材料的基本特性和优势，无需复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列举多个原因，但每个原因都是基础概念的记忆性知识（如玻璃纤维的生产成本、复合材料的比强度、化学惰性等），不需要复杂的分析或推理。正确选项已经明确列出了三个具体原因，考生只需识别和匹配这些基础知识点即可。相比等级1的简单定义题，该题目需要记忆和理解稍多的信息点，但不需要深入分析或综合应用，因此属于等级2难度。", "convertible": true, "correct_option": "glass fibers are very inexpensive to produce; these composites have relatively high specific strengths; and they are chemically inert in a wide variety of environments", "choice_question": "Which of the following are reasons why fiberglass-reinforced composites are used extensively?", "conversion_reason": "The answer is a list of standard reasons that can be converted into a multiple-choice format by presenting them as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Glass fibers exhibit superior creep resistance compared to carbon fibers at elevated temperatures", "B": "The thermal expansion coefficient of fiberglass composites perfectly matches most metal substrates", "C": "Fiberglass-reinforced composites demonstrate higher specific stiffness than aluminum alloys", "D": "The interfacial bonding strength between glass fibers and polymer matrices exceeds that of carbon fiber composites" }, "correct_answer": "A", "explanation": "Correct answer (A) is counterintuitive but true - glass fibers maintain better creep resistance than carbon fibers above 300°C due to their amorphous structure. Distractors exploit common misconceptions: (B) uses a 'perfect match' absolute statement when CTE is only relatively close, (C) confuses specific strength with specific stiffness where aluminum wins, and (D) leverages the false intuition that stronger fibers automatically mean better interfacial bonding.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 742, "question": "Ionic crystals usually reduce their surface energy through the polarization deformation and rearrangement of surface ions. Among the following ionic crystals, the one with the smallest surface energy is (a) $\\\\mathrm{CaF}{2}$ (b) $\\\\mathrm{Pb}\\\\mathrm{F}{2}$ c) $\\\\mathrm{Pb}\\\\mathbf{I}{2}$ (d) $\\\\mathbf{BaSO{4}}$ (e) SrsO4", "answer": "c", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且提供了明确的选项和答案 | 知识层次: 题目要求考生理解离子晶体表面能的概念，并能够分析不同离子晶体的极化变形和离子重排对表面能的影响。这需要考生将多个概念（如离子极化、离子半径、晶格能等）进行关联和综合分析，属于中等应用层次。 | 难度: 在选择题型中属于较高难度，需要综合理解离子晶体表面能的影响因素（如离子极化率、晶格能等），并比较不同化合物的离子特性（如PbI2中I-的大离子半径和高极化率导致表面能显著降低）。解题过程涉及多个概念的综合分析（极化效应、离子半径、晶格类型）以及化合物性质的横向比较，超出了简单记忆或单一概念应用的范畴。", "convertible": true, "correct_option": "c) $\\mathrm{Pb}\\mathbf{I}{2}$", "choice_question": "Ionic crystals usually reduce their surface energy through the polarization deformation and rearrangement of surface ions. Among the following ionic crystals, the one with the smallest surface energy is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dislocation density in annealed pure aluminum (99.99%) at room temperature", "B": "The dislocation density in work-hardened copper after 50% cold rolling", "C": "The dislocation density in single crystal silicon wafer used for semiconductor fabrication", "D": "The dislocation density in heavily doped n-type GaAs after thermal annealing" }, "correct_answer": "C", "explanation": "The correct answer is C because semiconductor-grade single crystal silicon has extremely low dislocation density (<100 cm^-2) due to stringent crystal growth conditions. Option A is misleading as even annealed aluminum has significant dislocation density (~10^6 cm^-2). Option B exploits the intuition that cold-worked metals should have high dislocation density (~10^10 cm^-2). Option D uses the misconception that doping increases dislocation density, while proper annealing actually reduces it in GaAs.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 301, "question": "What is heterogeneous nucleation?", "answer": "Heterogeneous nucleation occurs at heterogeneous interfaces, such as container walls, bubble interfaces, or on foreign substances (impurities or nucleating agents).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"heterogeneous nucleation\"进行文字解释和论述，答案提供了详细的定义和例子，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，仅需回答异质成核的定义及其发生的位置，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生识别并回忆\"heterogeneous nucleation\"的基本定义，属于最基础的概念记忆层次。题目正确选项直接给出了定义描述，不需要任何解释、比较或分析过程，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Heterogeneous nucleation occurs at heterogeneous interfaces, such as container walls, bubble interfaces, or on foreign substances (impurities or nucleating agents).", "choice_question": "Which of the following best describes heterogeneous nucleation?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Nucleation occurring at preferential sites with lower activation energy than homogeneous nucleation", "B": "Random formation of nuclei in a perfectly pure melt without any interfaces", "C": "Phase transformation initiated by external pressure rather than thermal fluctuations", "D": "Simultaneous nucleation at multiple identical sites with equal probability" }, "correct_answer": "A", "explanation": "Correct answer A describes the key characteristic of heterogeneous nucleation occurring at preferential sites like container walls or impurities, which reduces the activation energy barrier compared to homogeneous nucleation. Option B incorrectly describes homogeneous nucleation. Option C introduces a pressure-based nucleation mechanism which is irrelevant to the thermal fluctuation-driven nucleation process. Option D mimics homogeneous nucleation characteristics but falsely presents it as a special case of heterogeneous nucleation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2830, "question": "Determine the engineering strain εe and true strain εT when compressed from h to 0.5h, and explain which one better reflects the true deformation characteristics", "answer": "εe = (0.5 - 1)h / h = -50%; εT = ln(0.5h / h) = -69.3%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（工程应变和真实应变的计算）并应用相关公式（应变计算公式），答案也以具体数值形式呈现。虽然最后需要解释哪种应变更好反映变形特性，但主要考察点仍是计算能力。 | 知识层次: 题目主要涉及工程应变和真实应变的简单计算，需要直接套用基本公式进行计算，属于基本公式应用和简单计算的范畴。虽然题目要求解释哪种应变更能反映真实变形特性，但这一部分也属于对基本概念的直接应用，思维过程较为直接，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要计算工程应变和真实应变两个值，但都是直接套用基本公式（工程应变公式和自然对数公式），无需复杂推导或多步骤组合计算。题目主要考察对两种应变定义的理解和基本计算能力，属于选择题型中中等偏下的难度水平。", "convertible": true, "correct_option": "εe = -50%; εT = -69.3%", "choice_question": "When a material is compressed from height h to 0.5h, the engineering strain (εe) and true strain (εT) are:", "conversion_reason": "The original question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "εe = -50%; εT = -69.3%", "B": "εe = -50%; εT = -50%", "C": "εe = -69.3%; εT = -50%", "D": "εe = -100%; εT = -∞" }, "correct_answer": "A", "explanation": "The correct answer is A because engineering strain is calculated as (0.5h - h)/h = -50%, while true strain is ln(0.5h/h) = -69.3%. Option B incorrectly assumes true strain equals engineering strain, exploiting the common misconception that the two are interchangeable. Option C reverses the values, targeting confusion between the two strain definitions. Option D represents an extreme case of complete compression (h→0), which is not the scenario described, playing on the tendency to overgeneralize deformation limits.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2519, "question": "Explain the term: intermetallic compound", "answer": "A compound formed between metals.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释术语\"intermetallic compound\"，需要文字解释和论述，答案形式为简短的定义性陈述。 | 知识层次: 题目考查基本概念的记忆和理解，仅需要解释intermetallic compound的定义，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目仅要求识别和记忆\"intermetallic compound\"的基本定义，属于最基础的概念记忆层次。正确选项直接给出了术语的简单定义，不需要任何解释、分析或推理过程。这种题目在选择题中属于最简单的类型，只需基础概念记忆即可作答。", "convertible": true, "correct_option": "A compound formed between metals.", "choice_question": "Which of the following best describes an intermetallic compound?", "conversion_reason": "The answer is a standard definition that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A compound formed between metals with a fixed stoichiometric ratio and distinct crystal structure", "B": "A solid solution where metal atoms are randomly distributed in the crystal lattice", "C": "A mixture of two metals that retains the individual properties of each component", "D": "A metallic alloy with continuously variable composition range" }, "correct_answer": "A", "explanation": "The correct answer is A because intermetallic compounds are defined by having fixed stoichiometry and distinct crystal structures different from their constituent metals. Option B describes a solid solution, not an intermetallic. Option C describes a mechanical mixture, which is incorrect. Option D describes a continuous solid solution alloy, which is the opposite of an intermetallic compound's fixed stoichiometry. The distractors exploit common confusions between intermetallics and other types of metal mixtures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1556, "question": "Based on the relationship between dislocation motion and crystal slip, analyze the relationship between the Burgers vector of a pure screw dislocation and the direction of the dislocation line", "answer": "The Burgers vector is parallel to the direction of the dislocation line", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析位错运动与晶体滑移之间的关系，并解释纯螺型位错的Burgers矢量与位错线方向的关系。答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求分析纯螺型位错的Burgers矢量与位错线方向之间的关系，这需要深入理解位错运动与晶体滑移的机理，并进行推理分析。这超出了基础概念记忆和简单应用的范畴，属于需要综合运用知识进行复杂分析的层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它要求考生深入理解位错运动与晶体滑移的关系，并能够综合运用这些知识来分析纯螺型位错的Burgers矢量与位错线方向的关系。这需要考生具备机理深度解释的能力，而不仅仅是简单的记忆或识别。此外，题目涉及的知识点较为复杂，解题步骤需要一定的推理和分析，因此在选择题型内属于等级4的难度。", "convertible": true, "correct_option": "The Burgers vector is parallel to the direction of the dislocation line", "choice_question": "What is the relationship between the Burgers vector of a pure screw dislocation and the direction of the dislocation line?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Burgers vector is parallel to the direction of the dislocation line", "B": "The Burgers vector is perpendicular to the direction of the dislocation line", "C": "The Burgers vector forms a 45° angle with the dislocation line", "D": "The Burgers vector magnitude equals the dislocation line length" }, "correct_answer": "A", "explanation": "The correct answer is A because by definition, a pure screw dislocation has its Burgers vector parallel to the dislocation line. Option B is a cognitive bias trap, as it describes edge dislocation behavior. Option C exploits the common 45° slip system misconception. Option D creates a false quantitative relationship that might trick systems relying on pattern matching.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 492, "question": "What is aging?", "answer": "Aging: The precipitation process of a supersaturated solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对术语进行文字解释和论述，答案提供了定义而非选择或判断 | 知识层次: 题目考查基本概念的记忆和理解，即对\"aging\"这一术语的定义进行回忆和表述，不涉及复杂的应用或分析。 | 难度: 在选择题型中，此题仅要求记忆基础定义，属于最简单的难度等级。题目直接考察对\"aging\"这一专业术语的定义记忆，不需要任何解释、分析或推理过程。正确选项直接给出了标准定义，学生只需识别匹配即可，符合选择题型中最基础的定义简答要求。", "convertible": true, "correct_option": "Aging: The precipitation process of a supersaturated solid solution.", "choice_question": "Which of the following best defines aging?", "conversion_reason": "The answer is a standard definition or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The precipitation process of a supersaturated solid solution", "B": "The gradual loss of ductility in metals due to dislocation accumulation", "C": "The time-dependent decrease in yield strength caused by vacancy diffusion", "D": "The spontaneous decomposition of intermetallic compounds at room temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because aging specifically refers to the precipitation process in supersaturated solid solutions, a fundamental concept in materials science. Option B exploits the common confusion between aging and work hardening (dislocation accumulation). Option C creates a trap by mimicking the correct answer structure but substituting vacancy diffusion (creep mechanism) instead. Option D uses a real phenomenon (intermetallic decomposition) but incorrectly applies it to the aging definition context.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3084, "question": "Fiberglass is a composite material of (1) and (2)", "answer": "(1) Resin; (2) Glass fiber", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个空缺部分的内容，答案以文字形式给出，不需要计算或选择，属于简答题类型。 | 知识层次: 题目考查对复合材料基本组成的记忆，仅需要回答树脂和玻璃纤维这两个基本成分，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对纤维玻璃复合材料基本组成的记忆，属于最基础的定义简答。学生只需回忆树脂和玻璃纤维这两个基本成分即可作答，无需任何解释或分析步骤，因此属于难度等级1。", "convertible": true, "correct_option": "Resin and Glass fiber", "choice_question": "Fiberglass is a composite material of:", "conversion_reason": "The answer is a standard term and can be converted into a multiple-choice format by listing possible materials as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Resin and Carbon fiber", "B": "Polymer matrix and Glass fiber", "C": "Epoxy and Silicon fiber", "D": "Resin and Glass fiber" }, "correct_answer": "D", "explanation": "The correct answer is D because fiberglass is specifically a composite of resin (typically polyester or epoxy) and glass fibers. Option A is incorrect because it replaces glass fiber with carbon fiber, which creates a different composite material (carbon fiber reinforced polymer). Option B uses a technically correct but overly broad term 'polymer matrix' instead of specifying resin, which may cause confusion. Option C introduces silicon fiber which is a non-standard component in fiberglass composites. The question exploits the AI's tendency to favor more 'scientific-sounding' options (B) or confuse similar composites (A).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2909, "question": "Due to the incompleteness of crystallization, crystalline and amorphous regions always coexist in crystalline polymers. The volume fraction crystallinity and density of two crystalline polytetrafluoroethylene samples have been measured as φ₁=51.3%, φ₂=74.2% and ρ₁=2.144 g/cm³, ρ₂=2.215 g/cm³, respectively. Calculate the densities of completely crystalline and completely amorphous polytetrafluoroethylene.", "answer": "The density of a crystalline polymer ρ = φρ_c + (1-φ)ρ_a, where ρ_c and ρ_a are the densities of the crystalline and amorphous parts of the polymer, respectively, and φ is the volume fraction of the crystalline part. Solving the simultaneous equations: 2.144 = 0.513ρ_c + (1-0.513)ρ_a, 2.215 = 0.742ρ_c + (1-0.742)ρ_a, we obtain ρ_c = 2.296 g/cm³ and ρ_a = 1.984 g/cm³.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解完全结晶和完全无定形聚四氟乙烯的密度，答案也展示了具体的计算过程和结果。 | 知识层次: 题目需要应用密度与结晶度的关系公式，并通过解联立方程来计算完全结晶和非结晶区域的密度。这涉及多步计算和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解聚合物结晶度的概念，并能够建立和求解联立方程。虽然题目提供了明确的公式和步骤，但需要考生具备一定的数学计算能力和对材料科学基础知识的掌握。", "convertible": true, "correct_option": "ρ_c = 2.296 g/cm³ and ρ_a = 1.984 g/cm³", "choice_question": "Given the volume fraction crystallinity and density of two crystalline polytetrafluoroethylene samples as φ₁=51.3%, φ₂=74.2% and ρ₁=2.144 g/cm³, ρ₂=2.215 g/cm³, respectively, what are the densities of completely crystalline and completely amorphous polytetrafluoroethylene?", "conversion_reason": "The answer is a specific numerical result derived from solving simultaneous equations, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ρ_c = 2.296 g/cm³ and ρ_a = 1.984 g/cm³", "B": "ρ_c = 2.215 g/cm³ and ρ_a = 2.144 g/cm³", "C": "ρ_c = 2.144 g/cm³ and ρ_a = 2.215 g/cm³", "D": "ρ_c = 1.984 g/cm³ and ρ_a = 2.296 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer is derived from solving the system of equations based on the rule of mixtures for density: ρ = φρ_c + (1-φ)ρ_a. Using the given data points, we solve for ρ_c and ρ_a. Option B reverses the given densities, exploiting the tendency to confuse measured values with theoretical limits. Option C directly uses the measured densities as limits, a common oversimplification error. Option D inverts the correct values, targeting those who might misremember density relationships in polymers. The correct calculation requires careful algebraic manipulation of both data points simultaneously.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3939, "question": "13}\nSome hypothetical alloy is composed of 12.5 wt% of metal A and 87.5 wt% of metal B. If the densities of metals A and \\mathrm{B} are 4.27 and 6.35g / {cm}^{3}, respectively, whereas their respective atomic weights are 61.4 and 125.7g / mol, determine whether the crystal structure for this alloy is simple cubic, facercentered cubic, or body-centered cubic. Assume a unit cell edge length of 0.395nm.", "answer": "the crystal structure is body-centered cubic.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目需要通过数值计算和公式应用来确定合金的晶体结构类型，涉及密度、原子重量和晶胞边长等参数的计算。答案是基于计算结果得出的具体晶体结构类型，而非从选项中选择或简单的对错判断。 | 知识层次: 题目需要进行多步计算，包括质量分数转换为原子分数、计算单位晶胞中的原子数，并结合晶体结构的知识进行综合分析。虽然不涉及复杂的推理或机理解释，但需要关联多个概念并进行中等难度的计算。 | 难度: 在选择题中属于高难度，需要综合运用多个概念并进行复杂计算。题目涉及重量百分比、密度、原子量、晶体结构等多个知识点，解题步骤包括计算平均密度、摩尔分数、单位晶胞中的原子数等多个步骤，且需要综合分析计算结果与晶体结构的关系。这种多变量、多步骤的计算问题在选择题型中属于较复杂的难度水平。", "convertible": true, "correct_option": "body-centered cubic", "choice_question": "Some hypothetical alloy is composed of 12.5 wt% of metal A and 87.5 wt% of metal B. If the densities of metals A and B are 4.27 and 6.35g/cm³, respectively, whereas their respective atomic weights are 61.4 and 125.7g/mol, determine the crystal structure for this alloy given a unit cell edge length of 0.395nm. The possible crystal structures are:", "conversion_reason": "The question can be converted into a multiple-choice format because the answer is a standard term (body-centered cubic) and the question can be rephrased to ask for the correct crystal structure among given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "body-centered cubic", "B": "face-centered cubic", "C": "simple cubic", "D": "hexagonal close-packed" }, "correct_answer": "A", "explanation": "To determine the correct crystal structure, we must calculate the theoretical density of the alloy and compare it with the experimental density derived from unit cell parameters. The correct body-centered cubic structure yields a density matching the calculated value when considering the given composition and atomic weights. Option B (face-centered cubic) is a strong distractor because its higher packing factor makes it seem plausible for this alloy system, but the atomic size ratio makes this structure unfavorable. Option C (simple cubic) exploits the cognitive bias toward simpler structures, but its unrealistically low packing density makes it impossible for metallic alloys. Option D (hexagonal close-packed) is included to catch those who might assume close-packing based on the composition, but the atomic size difference prevents this structure from forming.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4914, "question": "For the following pair of materials, decide which has the larger thermal conductivity. Justify your choice. Pure silver; sterling silver (92.5 wt% Ag-7.5 wt% Cu)", "answer": "Pure silver will have a larger conductivity than sterling silver because the impurity atoms in the latter will lead to a greater degree of free electron scattering.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的热导率并给出理由，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求比较两种材料的导热性能，并解释原因。这需要理解热导率的基本概念（基础概念），同时需要分析杂质对自由电子散射的影响（概念关联和综合分析）。虽然不涉及复杂计算，但需要将多个知识点联系起来进行解释，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解热导率与材料纯度的关系，并分析杂质对自由电子散射的影响。虽然不需要复杂计算，但需要将多个概念（纯度、电子散射、热导率机制）进行关联分析才能正确判断。", "convertible": true, "correct_option": "Pure silver", "choice_question": "Which of the following materials has the larger thermal conductivity?", "conversion_reason": "The original question asks to decide which material has a larger thermal conductivity between two options, and the answer is a clear choice between the two. This can be easily converted into a multiple-choice question format by presenting the two materials as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Single crystal diamond (Type IIa) along <111> direction", "B": "Highly oriented pyrolytic graphite (HOPG) in-plane", "C": "Single crystal copper (99.999%) along <100> direction", "D": "Polycrystalline aluminum nitride (99.5% purity)" }, "correct_answer": "A", "explanation": "The correct answer is A because single crystal diamond (Type IIa) has the highest known thermal conductivity (~2000 W/m·K along <111>), exceeding even HOPG's in-plane conductivity (~2000 W/m·K). The interference strategies are: B exploits the common misconception that graphite's in-plane conductivity is highest; C uses ultra-pure copper's high conductivity (~400 W/m·K) to mislead about crystalline metals; D leverages ceramic material selection bias by using a high-purity technical ceramic with unexpectedly good conductivity (~320 W/m·K). All options require simultaneous consideration of crystal orientation, purity effects, and material class stereotypes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4443, "question": "The fracture strength of glass may be increased by etching away a thin surface layer. It is believed that the etching may alter surface crack geometry (i.e., reduce crack length and increase the tip radius). Compute the ratio of the original and etched crack tip radii for an eightfold increase in fracture strength if two-thirds of the crack length is removed.\n\\[\n\\text {", "answer": "the ratio of the original and etched crack tip radii is 21.3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，具体涉及计算裂纹尖端半径的比值，且答案以数值形式给出。 | 知识层次: 题目需要进行多步计算，涉及断裂强度的变化与裂纹几何参数的关系，需要应用格里菲斯断裂准则等概念，并进行数值计算和公式应用。虽然不涉及复杂的推理分析或创新设计，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解断裂强度的概念、裂纹几何形状的影响，并进行多步计算。题目要求计算原始和蚀刻后裂纹尖端半径的比值，涉及断裂力学的基本原理和公式应用。虽然题目提供了部分参数，但仍需要综合分析和计算才能得出正确结果。", "convertible": true, "correct_option": "21.3", "choice_question": "The fracture strength of glass may be increased by etching away a thin surface layer. It is believed that the etching may alter surface crack geometry (i.e., reduce crack length and increase the tip radius). What is the ratio of the original and etched crack tip radii for an eightfold increase in fracture strength if two-thirds of the crack length is removed?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "21.3", "B": "8.0", "C": "12.7", "D": "16.0" }, "correct_answer": "A", "explanation": "正确答案A(21.3)基于Griffith裂纹理论计算得出，考虑裂纹长度减少2/3和强度增加8倍的综合影响。干扰项B(8.0)直接使用强度增加倍数，忽略了裂纹几何变化；干扰项C(12.7)错误地线性组合了长度和强度因素；干扰项D(16.0)则错误地平方了强度增加倍数。这些干扰项利用了AI可能对裂纹尖端应力集中系数与强度关系的简化理解倾向。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4079, "question": "[d] Magnesium metal is very similar to aluminum, in terms of its physical and mechanical properties.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（Magnesium metal is very similar to aluminum, in terms of its physical and mechanical properties），并要求判断其正误（答案：T），符合判断题的特征。 | 知识层次: 题目考查对镁和铝金属物理和机械性能相似性的基本概念记忆，属于基础知识的认知层次。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆镁和铝在物理和机械性质上的相似性这一基础知识点即可作答，无需深入理解或分析。", "convertible": true, "correct_option": "T", "choice_question": "[d] Magnesium metal is very similar to aluminum, in terms of its physical and mechanical properties.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior under all loading conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain advanced ceramics can exhibit limited plasticity under specific conditions (e.g., high temperatures or hydrostatic pressure). The use of 'all' and 'under all loading conditions' makes this statement false. This tests understanding of ceramic behavior nuances and absolute term usage.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 736, "question": "What property must the medium exhibit for slurry peptization? (a) Acidic (b) Alkaline (c) Neutral", "answer": "b", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项（a）Acidic、（b）Alkaline、（c）Neutral中选择正确答案，符合选择题的特征。 | 知识层次: 题目考查对浆料胶溶作用所需介质性质的基础概念记忆，属于基本原理的记忆性知识 | 难度: 该题目属于基础概念记忆类型，仅需直接回忆\"slurry peptization\"所需介质的性质即可作答。在选择题型中属于最简单的难度等级，无需理解或辨析，仅需识别正确选项。", "convertible": true, "correct_option": "Alkaline", "choice_question": "What property must the medium exhibit for slurry peptization?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Acidic", "B": "Alkaline", "C": "Neutral", "D": "Depends on the zeta potential of the particles" }, "correct_answer": "B", "explanation": "The correct answer is Alkaline because peptization requires a medium that can provide stabilizing ions to prevent particle aggregation, typically achieved in alkaline conditions. Option A (Acidic) is a cognitive bias trap exploiting the common association of acids with dissolution. Option C (Neutral) appeals to intuitive simplicity but ignores the need for charge stabilization. Option D is a multi-level verification trap using a technically correct concept (zeta potential) but misleadingly suggesting it overrides the fundamental alkaline requirement.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3995, "question": "How does increasing the molecular weight of a semicrysatlline polymer affect its tensile strength?(a) Increases(b) Decreases\n\\", "answer": "The tensile strength of a semicrystalline polymer increases with increasing molecular weight. This effect is explained by the increased chain entanglements at higher molecular weights.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项（a）和（b）中选择正确答案，符合选择题的特征。 | 知识层次: 题目考查对半结晶聚合物分子量与其拉伸强度关系的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即分子量增加对半结晶聚合物拉伸强度的影响。正确选项直接给出了基本原理的解释，无需复杂辨析或深度理解。因此，该题目属于简单概念识别，直接记忆的难度等级。", "convertible": true, "correct_option": "Increases", "choice_question": "How does increasing the molecular weight of a semicrystalline polymer affect its tensile strength?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly indicates the correct choice. Therefore, it can be directly converted to a single-choice question by identifying the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases due to enhanced chain entanglement and reduced chain-end defects", "B": "Decreases as higher molecular weight leads to more amorphous regions", "C": "Remains constant because crystallinity percentage is the dominant factor", "D": "First increases then decreases beyond critical molecular weight" }, "correct_answer": "A", "explanation": "Correct answer A reflects the actual polymer physics where increased molecular weight enhances tensile strength through better chain entanglement and fewer weak chain ends. Distractor B exploits the common misconception that amorphous content necessarily weakens the material, while C plays on the cognitive bias of overemphasizing crystallinity. Distractor D is a professional trap mimicking the correct behavior of other properties like viscosity, creating verification complexity for AI systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 573, "question": "How do dislocations strengthen metallic materials?", "answer": "Dislocations can strengthen metallic materials.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释位错如何强化金属材料，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释位错如何强化金属材料，这需要深入理解位错与材料强度之间的机理关系，涉及位错运动、相互作用及其对材料力学性能的影响等多方面的综合分析。这超出了简单记忆或基本应用的范围，属于需要推理分析和机理解释的复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解位错的基本概念，还需要综合运用材料强化机理的知识，进行复杂现象的全面分析。正确选项虽然简洁，但背后隐含了对位错强化机制（如加工硬化、固溶强化、沉淀强化等）的深入理解，以及这些机制如何共同影响金属材料的强度。这种题目在选择题型中属于需要高阶思维和综合分析的难度水平。", "convertible": true, "correct_option": "Dislocations can strengthen metallic materials.", "choice_question": "How do dislocations strengthen metallic materials?", "conversion_reason": "The answer is a standard statement that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dislocation motion is hindered by other dislocations, requiring higher stress for plastic deformation", "B": "Dislocations increase the elastic modulus by reducing atomic spacing", "C": "Dislocations create vacancies that harden the material through solid solution strengthening", "D": "Dislocations reduce grain boundary mobility, preventing recrystallization" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental mechanism of work hardening where dislocation-dislocation interactions impede slip. Option B exploits confusion between elastic modulus (unaffected by dislocations) and yield strength. Option C combines vacancy formation (true) with incorrect strengthening mechanism (solid solution). Option D uses grain boundary effects which are unrelated to dislocation strengthening mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3628, "question": "Would you expect \\mathrm{UO}_{2} to have the sodium chloride, zinc blende, or fluoride structure?", "answer": "fluorite structure.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的三个结构选项（sodium chloride, zinc blende, fluoride）中选择一个正确答案，符合选择题的特征。 | 知识层次: 题目考查对常见晶体结构类型及其对应化合物的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆（UO2的晶体结构），但需要学生对三种常见晶体结构（NaCl、闪锌矿、萤石）有一定的理解和辨析能力。学生需要知道UO2通常采用萤石结构这一知识点，而不是简单地记忆定义。这比纯粹的概念识别（等级1）要求更高，但不需要复杂的分析或深度理解（等级3）。", "convertible": true, "correct_option": "fluorite structure", "choice_question": "Would you expect \\mathrm{UO}_{2} to have the sodium chloride, zinc blende, or fluoride structure?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer is a standard term that can be directly used as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fluorite structure", "B": "Sodium chloride structure", "C": "Zinc blende structure", "D": "Rutile structure" }, "correct_answer": "A", "explanation": "UO2 adopts the fluorite structure (CaF2 type) due to the large size difference between U4+ and O2- ions, where U4+ forms a face-centered cubic lattice with O2- occupying all tetrahedral sites. The sodium chloride structure (B) is incorrect because it requires similar cation/anion sizes. Zinc blende (C) is incorrect as it has only half the tetrahedral sites filled. Rutile (D) is a common oxide structure but incorrect for UO2. The key challenge is recognizing that while UO2 is an ionic compound like NaCl, its specific cation/anion size ratio mandates the fluorite structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4324, "question": "Compute the mass fraction of cementite in pearlite.", "answer": "the mass fraction of cementite in pearlite is 0.11.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算渗碳体在珠光体中的质量分数），并且答案是一个具体的数值（0.11），这表明解答过程需要应用公式和计算步骤。 | 知识层次: 题目涉及基本公式应用和简单计算，直接套用相图或杠杆定律即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需直接应用基本公式进行单一计算，无需复杂步骤或多公式组合。题目明确给出了计算目标（水泥体在珠光体中的质量分数），且正确选项直接呈现了计算结果，属于最基础的公式应用层次。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "0.11", "choice_question": "What is the mass fraction of cementite in pearlite?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.11", "B": "0.25", "C": "0.33", "D": "0.89" }, "correct_answer": "A", "explanation": "The correct answer is A (0.11) because pearlite consists of alternating layers of ferrite and cementite, with cementite accounting for approximately 11% of the mass. Option B (0.25) exploits the cognitive bias of expecting a rounder fraction. Option C (0.33) is a common misconception from confusing volume fraction with mass fraction. Option D (0.89) is a reversal trap, presenting the ferrite fraction instead of cementite.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4433, "question": "Would you expect Frenkel defects for anions to exist in ionic ceramics in relatively large concentrations? Why or why not?", "answer": "Frenkel defects for anions would not exist in appreciable concentrations because the anion is quite large and is highly unlikely to exist as an interstitial.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么Frenkel defects for anions在离子陶瓷中不会大量存在，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求对Frenkel缺陷在离子陶瓷中的存在情况进行解释，涉及对离子尺寸和晶体结构缺陷的综合分析，需要理解缺陷形成的机理和影响因素，并进行推理分析。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解Frenkel缺陷的基本概念，还需要深入掌握离子陶瓷中阴离子的特性（如尺寸较大），并能够进行复杂的推理分析。正确选项涉及对材料微观结构和缺陷形成机理的全面理解，需要考生综合运用多个知识点（如离子半径、间隙位置、缺陷形成能等）才能得出正确结论。这种在选择题中要求机理深度解释和复杂现象全面分析的题目，对考生的知识掌握深度和综合分析能力提出了很高要求。", "convertible": true, "correct_option": "Frenkel defects for anions would not exist in appreciable concentrations because the anion is quite large and is highly unlikely to exist as an interstitial.", "choice_question": "Would you expect Frenkel defects for anions to exist in ionic ceramics in relatively large concentrations?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because the high temperature processing of ceramics creates sufficient vacancies for anion Frenkel pairs", "B": "No, because the anion is quite large and is highly unlikely to exist as an interstitial", "C": "Yes, because the charge neutrality condition requires equal numbers of cation and anion Frenkel defects", "D": "No, because anions typically have lower formation energies for Schottky defects compared to Frenkel defects" }, "correct_answer": "B", "explanation": "The correct answer is B because anions in ionic ceramics are generally too large to fit into interstitial sites, making Frenkel defects energetically unfavorable. Option A is a temperature-based cognitive bias, exploiting the common knowledge that high temperatures increase defect concentrations without considering size constraints. Option C creates a charge neutrality misconception by implying defect types must balance, which is not required. Option D introduces a Schottky defect comparison that, while true, is irrelevant to the specific question about Frenkel defects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3827, "question": "Consider a Al-25% Si alloy. Determine if the alloy is hypo eutectic or hyper eutectic.", "answer": "hyper eutectic", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过分析合金成分来判断其属于亚共晶还是过共晶，需要文字解释和论述，而不是简单的选择或判断。答案也是以文字形式给出，而非数值计算结果。 | 知识层次: 题目考查对共晶合金分类的基本概念记忆和理解，只需知道Al-Si合金的共晶点成分(12.6% Si)即可判断25% Si属于过共晶(hyper eutectic)，不需要复杂计算或分析过程。 | 难度: 该题目属于基础概念记忆类型，仅需知道Al-Si合金的共晶点（约12.6% Si）即可直接判断25% Si属于过共晶成分。选择题型中无需计算或推导，属于最简单的定义识别类题目。", "convertible": true, "correct_option": "hyper eutectic", "choice_question": "Consider a Al-25% Si alloy. Is the alloy hypo eutectic or hyper eutectic?", "conversion_reason": "The answer is a standard term (hyper eutectic) which can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hypo-eutectic, because 25% Si is below the eutectic composition in the Al-Si system", "B": "Hyper-eutectic, because 25% Si exceeds the eutectic composition of 12.6% Si", "C": "Neither, because 25% Si is exactly at the eutectic composition", "D": "Cannot be determined without knowing the cooling rate" }, "correct_answer": "B", "explanation": "The correct answer is B because the eutectic composition in the Al-Si system is 12.6% Si, making 25% Si hyper-eutectic. Option A is a cognitive bias trap, exploiting the common mistake of assuming 'hypo' means 'below' without checking actual phase diagram values. Option C is a professional intuition trap, using an incorrect memorized eutectic point. Option D is a multi-level verification trap, introducing an irrelevant parameter (cooling rate) that doesn't affect the hypo/hyper classification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4603, "question": "For the following pair of materials, decide which has the larger thermal conductivity. Justify your choice. Linear polyethylene; branched polyethylene.", "answer": "The linear polyethylene will have the larger conductivity than the branched polyethylene because the former will have the higher degree of crystallinity. Linear polymers have higher degrees of crystallinity than branched polymers. Since heat transfer is accomplished by molecular chain vibrations, and the coordination of these vibrations increases with percent crystallinity, the higher the crystallinity, the greater the thermal conductivity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对两种材料的导热性进行比较并给出理由，答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目要求比较两种聚乙烯的热导率，并解释原因。这需要理解线性聚乙烯和支化聚乙烯的结晶度差异，以及结晶度对热导率的影响。虽然涉及基础概念，但需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解线性聚乙烯和支化聚乙烯的结晶度差异，并关联结晶度与热导率的关系。虽然不涉及复杂计算，但需要综合应用材料科学中的多个概念进行比较分析。", "convertible": true, "correct_option": "Linear polyethylene", "choice_question": "Which of the following materials has the larger thermal conductivity?", "conversion_reason": "The original question asks to compare the thermal conductivity of two materials and justify the choice. The answer provides a clear and definitive choice (linear polyethylene) with a justification. This can be converted into a multiple-choice question by presenting the two materials as options and identifying the correct one based on the given answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Highly oriented pyrolytic graphite (parallel to basal planes)", "B": "Single crystal diamond along <111> direction", "C": "Silver at 20°C", "D": "Bulk copper at cryogenic temperatures (20K)" }, "correct_answer": "A", "explanation": "Highly oriented pyrolytic graphite has the highest known thermal conductivity (~2000 W/mK parallel to basal planes) due to its perfect crystalline alignment and strong in-plane covalent bonds. The traps: B) Diamond's isotropic thermal conductivity (~2000 W/mK) is slightly lower than graphite's in-plane value. C) Silver's high conductivity (~430 W/mK) is misleading as it's the best among metals but inferior to carbon allotropes. D) Copper's cryogenic conductivity (~10,000 W/mK) seems plausible but this peak value occurs only near 20K and drops sharply at higher temperatures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4129, "question": "The strong outer sheets of sandwich panels are separated by a layer of material that is(a) less dense than the outer sheet material(b) more dense than the outer sheet material", "answer": "The strong outer sheets of sandwich panels are separated by a layer of material that is less dense than the outer sheet material.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目提供了两个选项(a)和(b)，要求从中选择正确的描述，符合选择题的特征 | 知识层次: 题目考查对夹层板结构的基本概念的记忆和理解，即夹层板中间层材料的密度特性。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别和回忆三明治板结构中夹层材料的密度特性与外表层材料的关系。题目直接给出了定义性的知识，无需复杂分析或比较，属于最简单的概念识别级别。", "convertible": true, "correct_option": "less dense than the outer sheet material", "choice_question": "The strong outer sheets of sandwich panels are separated by a layer of material that is", "conversion_reason": "The original question is already in a multiple-choice format with two distinct options (a) and (b). The answer provided corresponds to one of these options, making it straightforward to convert into a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "a viscoelastic polymer with strain-rate dependent modulus", "B": "a ceramic foam with negative Poisson's ratio", "C": "a metallic honeycomb structure with anisotropic stiffness", "D": "a syntactic foam with controlled porosity distribution" }, "correct_answer": "A", "explanation": "The correct answer is A because sandwich panel cores must effectively transfer shear stresses while maintaining light weight, which requires strain-rate dependent energy absorption. Option B exploits the misconception that negative Poisson's ratio materials are always optimal for core layers. Option C targets the intuitive appeal of metallic structures while ignoring their density limitations. Option D uses a technically advanced but situationally inappropriate material by overemphasizing porosity control over dynamic loading performance.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 911, "question": "What is the difference in the driving force for nucleation during recrystallization and solidification?", "answer": "The driving force for nucleation during solidification is the chemical potential difference between the new and old phases, while the driving force for recrystallization is only the stored energy of deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释两种不同过程中成核驱动力的差异，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求比较两种不同相变过程（再结晶和凝固）的成核驱动力，涉及对材料科学中相变和变形储存能等概念的理解和应用。虽然不需要复杂的计算，但需要对多个概念进行关联和综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求区分两种不同相变过程（再结晶和凝固）的成核驱动力来源，涉及对化学势差和变形储存能等概念的理解和对比。虽然不需要多步计算，但需要综合分析不同相变机制的特点，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "The driving force for nucleation during solidification is the chemical potential difference between the new and old phases, while the driving force for recrystallization is only the stored energy of deformation.", "choice_question": "What is the difference in the driving force for nucleation during recrystallization and solidification?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The driving force for nucleation during solidification is the chemical potential difference between the new and old phases, while the driving force for recrystallization is only the stored energy of deformation", "B": "Both processes are driven by the same thermodynamic principles, with the only difference being the magnitude of the driving force", "C": "Recrystallization is driven by surface energy reduction, while solidification is driven by chemical potential difference", "D": "Solidification is driven by the stored energy of deformation, while recrystallization is driven by chemical potential difference" }, "correct_answer": "A", "explanation": "The correct answer A precisely distinguishes the fundamental difference between these two nucleation processes. Option B is incorrect because it ignores the different physical origins of driving forces. Option C reverses the actual driving force for recrystallization (surface energy is not the primary driver). Option D completely swaps the driving forces between the two processes, creating a particularly dangerous trap for those relying on superficial pattern recognition rather than deep understanding of the underlying mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2173, "question": "When stretching a copper single crystal, if the direction of the tensile axis is [001], $\\\\sigma=10^{6}$ Pa. Calculate the force on the screw dislocation line with Burgers vector $b=$ $\\\\frac{a}{2}$ [101] on the (111) plane $(a_{\\\\mathrm{Cu}}=0.36\\\\mathrm{nm})$.", "answer": "Let the resolved shear stress of the applied tensile stress along the [101] direction on the (111) slip plane be $\\\\tau$, then $$ x \\\\tau=\\\\sigma{\\\\cos}\\\\varphi{\\\\cos}\\\\lambda\\n $$\\n where, $\\\\varphi$ is the angle between [001] and the normal [111] of the (111) plane, $\\\\lambda$ is the angle between [001] and the [101] direction. \\n\\nSo $$ \\\\tau=10^{6}\\\\times{\\\\frac{1}{{\\\\sqrt{1}}\\\\times{\\\\sqrt{3}}}}\\\\times{\\\\frac{1}{\\\\sqrt{2}}}=4.0825\\\\times10^{5}{\\\\mathrm{~Pa}}\\n $$\\n If the force on the screw dislocation line is $F_{\\\\mathrm{d}}$, then $$ F_{\\\\mathrm{d}}=\\\\tau b=4.0825\\\\times10^{5}\\\\times{\\\\frac{\\\\sqrt{2}}{2}}\\\\times0.36\\\\times10^{-9}=1.039\\\\times10^{-4}~{\\\\mathrm{N/m}}\\n $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程中涉及到了应力分解、角度计算和力的计算，最终给出了具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括计算分解剪应力、角度计算以及最终的力计算，涉及概念关联和综合分析。虽然不涉及复杂的推理分析或机理解释，但需要一定的理解和应用能力。 | 难度: 在选择题型中，这道题目属于高难度等级。原因如下：", "convertible": true, "correct_option": "1.039×10⁻⁴ N/m", "choice_question": "When stretching a copper single crystal, if the direction of the tensile axis is [001], σ=10⁶ Pa, the force on the screw dislocation line with Burgers vector b= a/2 [101] on the (111) plane (a_Cu=0.36 nm) is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.039×10⁻⁴ N/m", "B": "2.078×10⁻⁴ N/m", "C": "5.196×10⁻⁵ N/m", "D": "3.117×10⁻⁴ N/m" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算Peach-Koehler力公式得到的。干扰项B是错误地将剪切应力分量加倍的结果，利用了数值接近的认知偏差。干扰项C是错误地使用了弹性模量而非剪切模量计算的结果，属于材料参数混淆陷阱。干扰项D是错误地将所有滑移系激活时的叠加力，属于多系统混淆陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3160, "question": "What type does the alloy phase Fe3C belong to, and what are its structural characteristics?", "answer": "Fe3C is a complex lattice interstitial compound with an orthorhombic crystal system. Its unit cell contains 12 iron atoms and 4 carbon atoms. The iron atoms are arranged in a close-packed manner, forming octahedrons, with carbon atoms located in the octahedral interstitial sites. The corner atoms of the octahedrons are shared by two adjacent octahedrons, and there is a certain orientation between the octahedrons.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求解释Fe3C合金相的类型和结构特征，答案提供了详细的文字描述和论述，没有涉及选择、判断或计算。 | 知识层次: 题目考查对Fe3C合金相的类型和结构特征的基本概念记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题中属于较高难度，需要掌握复杂概念体系。题目要求考生不仅知道Fe3C的分类（复杂间隙化合物），还需理解其正交晶系结构特征、晶胞组成（12Fe+4C）、铁原子密排方式形成的八面体间隙，以及碳原子在其中的位置分布。这些知识点涉及晶体结构、原子排列和间隙理论等多个相互关联的概念，需要考生具备较强的空间想象能力和对金属学基础理论的深入理解。", "convertible": true, "correct_option": "Fe3C is a complex lattice interstitial compound with an orthorhombic crystal system. Its unit cell contains 12 iron atoms and 4 carbon atoms. The iron atoms are arranged in a close-packed manner, forming octahedrons, with carbon atoms located in the octahedral interstitial sites. The corner atoms of the octahedrons are shared by two adjacent octahedrons, and there is a certain orientation between the octahedrons.", "choice_question": "Which of the following correctly describes the type and structural characteristics of the alloy phase Fe3C?", "conversion_reason": "The answer is a standard description of the alloy phase Fe3C, which can be used as the correct option in a multiple-choice question. The question can be rephrased to ask for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fe3C is a complex lattice interstitial compound with orthorhombic structure where carbon occupies octahedral sites in an iron matrix", "B": "Fe3C is a simple substitutional solid solution with cubic structure where carbon randomly replaces iron atoms", "C": "Fe3C is an intermetallic compound with hexagonal close-packed structure and stoichiometric 3:1 Fe-C ratio", "D": "Fe3C is an interstitial solid solution with face-centered cubic structure where carbon fills tetrahedral voids" }, "correct_answer": "A", "explanation": "The correct answer is A because Fe3C (cementite) is indeed an orthorhombic interstitial compound with carbon in octahedral sites. Option B is wrong but tempting as it describes a common solid solution scenario. Option C uses correct stoichiometry but wrong crystal system, exploiting hcp familiarity. Option D mimics common FCC interstitial solutions like austenite, creating phase confusion. Advanced AIs might default to simpler cubic structures (B/D) or recognize stoichiometry but misassign crystal system (C).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 11, "question": "What are the characteristics of van der Waals bonds?", "answer": "Van der Waals bonds are formed through molecular forces, and the molecular forces are very weak.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释van der Waals bonds的特性，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对范德华键基本特征的定义和记忆，属于基础概念的理解层面 | 难度: 在选择题型中，该题目仅要求记忆和识别范德华键的基本定义和特征，属于基础概念记忆层次。正确选项直接描述了范德华键的形成方式和强度，无需复杂推理或概念间的比较分析，因此属于最简单的难度等级。", "convertible": true, "correct_option": "Van der Waals bonds are formed through molecular forces, and the molecular forces are very weak.", "choice_question": "Which of the following describes the characteristics of van der Waals bonds?", "conversion_reason": "The answer is a standard description of van der Waals bonds, which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Van der Waals bonds are formed through molecular forces, and the molecular forces are very weak.", "B": "Van der Waals bonds are directional covalent interactions with intermediate strength.", "C": "Van der Waals bonds result from electron transfer between atoms, creating strong ionic attractions.", "D": "Van der Waals bonds exhibit metallic bonding characteristics with delocalized electrons." }, "correct_answer": "A", "explanation": "The correct answer is A because van der Waals bonds are indeed weak intermolecular forces arising from temporary dipoles. Option B is incorrect as it confuses van der Waals with covalent bonds by suggesting directionality and intermediate strength. Option C is a trap for those confusing van der Waals with ionic bonding through electron transfer. Option D exploits the common misconception that all bonding involves electron delocalization like metallic bonds.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3499, "question": "Why is it often easy to form white iron on the surface layer and thin-walled areas of the same casting?", "answer": "Because the undercooling degree is large and the cooling rate is fast at the surface layer and thin-walled areas, it is easy to obtain white iron.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么在铸件的表层和薄壁区域容易形成白口铁，答案提供了文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目需要理解白口铁形成的条件（过冷度和冷却速率），并将其与铸件表面层和薄壁区域的特点联系起来进行分析。这涉及到多个概念的关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及铸铁凝固过程中的冷却速率和过冷度对组织形成的影响，要求考生能够将表面层和薄壁区域的冷却条件与白口铁的形成联系起来。虽然不需要复杂的计算，但需要对材料科学中的凝固原理有较好的理解，并能综合分析不同区域的冷却条件差异对组织的影响。", "convertible": true, "correct_option": "Because the undercooling degree is large and the cooling rate is fast at the surface layer and thin-walled areas, it is easy to obtain white iron.", "choice_question": "Why is it often easy to form white iron on the surface layer and thin-walled areas of the same casting?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be kept as is or slightly rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because the undercooling degree is large and the cooling rate is fast at the surface layer and thin-walled areas, it is easy to obtain white iron.", "B": "Due to higher carbon diffusion rates in thin sections promoting cementite formation over graphite nucleation.", "C": "Because surface oxidation creates nucleation sites that favor the metastable cementite phase.", "D": "As a result of thermal stress gradients inducing martensitic transformation in surface layers." }, "correct_answer": "A", "explanation": "The correct answer A identifies the key factors of high undercooling and fast cooling rates that suppress graphite formation. Option B reverses the actual diffusion dynamics (thin sections have less time for carbon diffusion). Option C introduces an irrelevant surface oxidation mechanism. Option D incorrectly invokes martensitic transformation which doesn't occur in cast irons. These distractors exploit common misconceptions about diffusion kinetics, surface effects, and phase transformation mechanisms in cast irons.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1414, "question": "What is the electron magnetic moment?", "answer": "The electron magnetic moment refers to the orbital magnetic moment generated by the electron's motion around the nucleus and the spin magnetic moment produced by the electron's spin.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"electron magnetic moment\"进行文字解释和论述，答案提供了概念的定义和组成要素，属于需要文字说明的简答题类型。 | 知识层次: 题目考查电子磁矩的基本定义和组成，属于基础概念的记忆和理解范畴，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度。虽然涉及电子磁矩的两个组成部分（轨道磁矩和自旋磁矩），但仅要求考生记忆并识别定义层面的内容，不需要进行复杂的概念体系阐述或比较分析。题目正确选项直接给出了完整定义，符合选择题型中对基础概念记忆的要求。", "convertible": true, "correct_option": "The electron magnetic moment refers to the orbital magnetic moment generated by the electron's motion around the nucleus and the spin magnetic moment produced by the electron's spin.", "choice_question": "Which of the following correctly describes the electron magnetic moment?", "conversion_reason": "The answer is a standard definition of the electron magnetic moment, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The electron magnetic moment refers to the orbital magnetic moment generated by the electron's motion around the nucleus and the spin magnetic moment produced by the electron's spin.", "B": "The electron magnetic moment is solely determined by the electron's orbital angular momentum around the nucleus, analogous to classical current loops.", "C": "The electron magnetic moment arises exclusively from the electron's spin, with no contribution from orbital motion.", "D": "The electron magnetic moment is a fixed fundamental constant equal to the Bohr magneton, independent of orbital or spin contributions." }, "correct_answer": "A", "explanation": "The correct answer A comprehensively describes both components of the electron magnetic moment. Option B exploits the classical analogy trap by ignoring quantum spin contribution. Option C uses the common misconception that spin is the only source. Option D creates confusion by mixing the concept with Bohr magneton's fixed value while neglecting the dynamic nature of magnetic moments.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4158, "question": "Match the following material types with their light transmission characteristics: Polycrystalline and nonporous electrical insulators - Translucent, Transparent, Opaque", "answer": "Polycrystalline and nonporous electrical insulators are translucent.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项（Translucent, Transparent, Opaque）中选择与材料类型（Polycrystalline and nonporous electrical insulators）相匹配的光传输特性，符合选择题的特征。 | 知识层次: 题目考查对材料类型及其光传输特性的基本概念记忆和理解，属于基础知识的直接应用，无需复杂分析或综合推理。 | 难度: 在选择题型中，该题目属于简单概念识别，直接记忆的难度。题目要求匹配材料类型与其透光特性，正确选项直接给出了明确的定义（半透明），无需复杂分析或深度理解，仅需基础概念的记忆即可作答。", "convertible": true, "correct_option": "Translucent", "choice_question": "What is the light transmission characteristic of polycrystalline and nonporous electrical insulators?", "conversion_reason": "The original question is already in a multiple-choice format where the answer is a single correct option among given choices. It can be directly converted to a single-choice question by presenting the options separately.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Translucent", "B": "Transparent", "C": "Opaque", "D": "Variable transparency depending on grain size" }, "correct_answer": "A", "explanation": "Polycrystalline and nonporous electrical insulators are typically translucent due to light scattering at grain boundaries, even without porosity. Option B (Transparent) exploits the cognitive bias that nonporous materials should be transparent, ignoring polycrystalline effects. Option C (Opaque) is a common overgeneralization from porous insulators. Option D creates a professional intuition trap by suggesting a real material science phenomenon (grain size effects) that doesn't apply to nonporous systems where scattering dominates regardless of grain size.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1033, "question": "Heterogeneous nucleation", "answer": "Heterogeneous nucleation: The formation of crystal nuclei in liquid metal preferentially occurs on the surfaces of foreign substances (mold walls or impurities) or at locations with temperature inhomogeneity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对“Heterogeneous nucleation”进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即异质成核的定义和基本原理，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生准确记忆并理解\"异质形核\"的基本定义和发生条件，涉及对专业术语（如foreign substances, temperature inhomogeneity）的掌握。虽然不需要复杂的分析过程，但需要考生能够区分异质形核与其他形核方式的本质区别，属于概念解释和描述层面的考查。相比简单定义复述题（等级1）更具专业性，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "The formation of crystal nuclei in liquid metal preferentially occurs on the surfaces of foreign substances (mold walls or impurities) or at locations with temperature inhomogeneity.", "choice_question": "Which of the following best describes heterogeneous nucleation?", "conversion_reason": "The answer is a standard definition of a scientific term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The formation of crystal nuclei in liquid metal preferentially occurs on the surfaces of foreign substances (mold walls or impurities) or at locations with temperature inhomogeneity", "B": "The spontaneous formation of crystal nuclei in a perfectly homogeneous liquid metal without any external influence", "C": "The nucleation process that occurs at grain boundaries during solid-state phase transformations", "D": "The simultaneous formation of multiple crystal nuclei with different crystallographic orientations in a supercooled liquid" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines heterogeneous nucleation as requiring foreign surfaces or temperature gradients. Option B describes homogeneous nucleation, a common confusion. Option C is a grain boundary phenomenon unrelated to liquid-solid transformation. Option D mixes concepts of nucleation and crystallographic orientation, creating a multi-parameter trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4072, "question": "Select T / F for the following statement regarding copper & copper alloys: Copper is one of just a few metals that can be found in metallic form in nature.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（T/F），属于典型的判断题形式 | 知识层次: 题目考查对铜及其合金基本性质的记忆，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念正误判断题，仅需记忆铜在自然界中的存在形式这一简单事实即可作答。在选择题型中，这类直接考察基础概念记忆的题目属于最低难度等级，不需要任何分析或推理过程。", "convertible": true, "correct_option": "T", "choice_question": "Select T / F for the following statement regarding copper & copper alloys: Copper is one of just a few metals that can be found in metallic form in nature.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All copper alloys exhibit higher electrical conductivity than pure copper.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because most alloying elements actually decrease copper's conductivity. Pure copper has the highest electrical conductivity (100% IACS), while common alloys like brass and bronze typically have lower conductivity (20-60% IACS). The statement uses an absolute term 'all' which makes it incorrect, though there are very rare exceptions where specific alloying might slightly improve certain conductivity properties under special conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 223, "question": "In the phase diagram of the SiO2 system, find two examples of reversible polymorphic transformations", "answer": "Reversible polymorphic transformations: β-quartz ↔ α-quartz, α-quartz ↔ tridymite", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举两个可逆多晶型转变的例子，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对SiO2系统相图中可逆多晶转变的基本概念记忆，仅需列举两个例子，不涉及复杂分析或综合应用 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确回忆并识别SiO2系统中可逆的多晶型转变实例。这要求考生不仅记住定义，还要能区分不同相变类型的具体例子。相比单纯的定义复述（等级1），这种题目需要更深入的概念理解和记忆。", "convertible": true, "correct_option": "β-quartz ↔ α-quartz, α-quartz ↔ tridymite", "choice_question": "In the phase diagram of the SiO2 system, which of the following are examples of reversible polymorphic transformations?", "conversion_reason": "The answer is a standard set of terms (reversible polymorphic transformations) that can be presented as options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "β-quartz ↔ α-quartz", "B": "Cristobalite ↔ Tridymite", "C": "α-quartz ↔ Coesite", "D": "Stishovite ↔ β-quartz" }, "correct_answer": "A", "explanation": "The correct answer is A because β-quartz to α-quartz is a well-known reversible displacive transformation in the SiO2 system. Option B is a cognitive bias trap - while both are high-temperature polymorphs, their transformation is reconstructive and irreversible. Option C exploits professional intuition by pairing two common polymorphs but their transformation requires bond breaking (irreversible). Option D is a multi-level verification trap combining a high-pressure phase with a low-pressure phase, creating an impossible transition path.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 83, "question": "Explain the meaning of the symbol Ca_{i}^{* *}", "answer": "Ca2+ is located at the interstitial site of the lattice", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释符号的含义，需要文字解释和论述，答案也是以文字形式给出解释说明 | 知识层次: 题目考查对材料科学中缺陷符号的基本概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目要求考生解释符号Ca_{i}^{* *}的含义，并选择正确的选项。这属于概念解释和描述的层次，需要考生理解并记忆Ca2+位于晶格间隙位置的定义。虽然需要一定的知识掌握，但不需要复杂的分析或推理，因此属于中等难度。", "convertible": true, "correct_option": "Ca2+ is located at the interstitial site of the lattice", "choice_question": "What is the meaning of the symbol Ca_{i}^{* *}?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ca2+ is located at the interstitial site of the lattice", "B": "A neutral calcium atom occupying a substitutional site with double positive charge", "C": "A doubly ionized calcium vacancy in the crystal structure", "D": "An excited state calcium ion at a regular lattice site" }, "correct_answer": "A", "explanation": "The correct answer is A because the notation Ca_{i}^{**} specifically denotes a doubly charged calcium ion (Ca2+) occupying an interstitial site (i) in the lattice. Option B is a cognitive bias trap - it uses the correct charge state but incorrectly places it at a substitutional site. Option C exploits the Kröger-Vink notation confusion by suggesting a vacancy (which would be V_{Ca}^{''}). Option D is a professional intuition trap - while the double asterisk could be misconstrued as an excited state, the correct interpretation in defect chemistry is always the charge state.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4011, "question": "Is solid ductile cast iron (ferrite solid solution + embedded graphite spheres) a two-phase material system?", "answer": "Yes, it is a two-phase system because there is a physical boundary beyond the particle level that separates chemically and structurally distinct volumes.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（\"Is solid ductile cast iron... a two-phase material system?\"），答案明确给出了\"Yes\"的判断并提供了简要解释，符合判断题的特征。 | 知识层次: 题目考查对两相材料系统基本概念的记忆和理解，涉及材料组成和相的定义，属于基础概念层次。 | 难度: 该题目属于基础概念正误判断，仅需记忆材料科学中两相系统的定义即可作答。题目直接询问是否属于两相系统，并给出明确的结构描述（铁素体固溶体+石墨球），只需判断是否符合两相系统的定义特征（存在物理边界分隔化学/结构不同的区域）。在选择题型中属于最基础的认知层级，无需复杂推理或概念关联。", "convertible": true, "correct_option": "Yes, it is a two-phase system because there is a physical boundary beyond the particle level that separates chemically and structurally distinct volumes.", "choice_question": "Is solid ductile cast iron (ferrite solid solution + embedded graphite spheres) a two-phase material system?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All solid solutions exhibit complete miscibility across the entire composition range at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While some solid solutions show complete miscibility, many systems have solubility limits even at elevated temperatures, and most exhibit limited solubility at room temperature. The use of 'all' makes this statement incorrect as it's an absolute claim that doesn't account for systems with partial solubility or immiscibility.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2049, "question": "What is the quantitative relationship between the critical nucleus radius r_k and the undercooling ΔT?", "answer": "The critical nucleus radius r_k, whose size is related to the undercooling, is given by r_k=(2σT_m)/(L_m)×1/ΔT", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求定量描述临界核半径r_k与过冷度ΔT之间的关系，并给出了具体的计算公式，需要应用公式进行计算和推导 | 知识层次: 题目要求应用给定的公式进行定量计算，涉及基本公式的直接套用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅涉及单一公式的直接应用，即临界核半径与过冷度之间的定量关系。学生只需识别并正确套用给定公式即可作答，无需进行额外的计算或概念分析。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "r_k=(2σT_m)/(L_m)×1/ΔT", "choice_question": "What is the quantitative relationship between the critical nucleus radius r_k and the undercooling ΔT?", "conversion_reason": "The answer is a specific formula, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "r_k=(2σT_m)/(L_m)×1/ΔT", "B": "r_k=(2σT_m)/(L_m)×ΔT", "C": "r_k=(2σΔT)/(L_mT_m)", "D": "r_k=(2L_m)/(σT_mΔT)" }, "correct_answer": "A", "explanation": "正确答案A来自经典形核理论，正确表达了临界核半径与过冷度的反比关系。干扰项B错误地将ΔT放在分子位置，利用了常见比例关系直觉陷阱。干扰项C通过交换T_m和ΔT的位置制造混淆，利用了参数位置记忆偏差。干扰项D完全颠倒了各参数的分子分母关系，是针对公式结构记忆不牢的深度陷阱。所有干扰项都保持了相似的数学结构但通过关键参数位置变化制造认知困难。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3652, "question": "FCC lead has a lattice parameter of 0.4949 nm and contains one vacancy per 500 Pb atoms. Calculate the number of vacancies per gram of Pb.", "answer": "the number of vacancies per gram of pb is 5.82 × 10^18 vacancies/g.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及晶格参数和空位浓度的计算，答案也是具体的数值结果。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，需要根据给定的晶格参数和空位浓度计算每克铅中的空位数。虽然需要理解FCC结构和空位的概念，但计算过程相对直接，属于基本公式的直接套用和简单计算。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用基本公式（如计算单位晶胞中的原子数、摩尔质量等），但解题步骤相对直接，不涉及多个公式的组合或复杂的概念分析。学生只需正确套用公式并进行简单计算即可得出答案，因此难度等级为2。", "convertible": true, "correct_option": "5.82 × 10^18 vacancies/g", "choice_question": "FCC lead has a lattice parameter of 0.4949 nm and contains one vacancy per 500 Pb atoms. The number of vacancies per gram of Pb is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.82 × 10^18 vacancies/g", "B": "1.16 × 10^19 vacancies/g", "C": "2.91 × 10^18 vacancies/g", "D": "3.49 × 10^18 vacancies/g" }, "correct_answer": "A", "explanation": "The correct answer involves calculating the number of Pb atoms per gram (using FCC geometry and atomic weight of Pb), then dividing by 500 to get vacancies. Option B doubles the correct value by incorrectly assuming two vacancies per 500 atoms. Option C comes from using the BCC atomic packing factor by mistake. Option D results from miscalculating the atomic density by using the wrong power of 10 in unit conversion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2074, "question": "Point out the errors in the following concepts and correct them: (15) Regardless of the temperature distribution, common pure metals always grow with a dendritic interface.", "answer": "Only under negative temperature gradient conditions, common pure metals.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。答案形式也是通过文字说明来纠正错误概念。 | 知识层次: 题目要求指出并纠正关于纯金属生长形态的错误概念，需要理解温度梯度对金属生长形态的影响，并能够将这一概念与具体条件（负温度梯度）联系起来。这涉及到对金属凝固过程的基本原理的应用和综合分析，而不仅仅是简单的记忆或直接套用。 | 难度: 在选择题中属于中等难度，需要理解金属凝固过程中的温度梯度概念，并能区分不同条件下的界面生长形态。题目要求识别错误概念并选择正确表述，涉及对纯金属凝固行为的综合分析，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "Only under negative temperature gradient conditions, common pure metals", "choice_question": "Under what conditions do common pure metals grow with a dendritic interface?", "conversion_reason": "The original short answer question asks for a correction to a specific concept, which can be rephrased as a multiple-choice question by asking about the conditions under which the phenomenon occurs. The provided answer is a standard term that can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Only under negative temperature gradient conditions", "B": "When the solidification rate exceeds 1 mm/s regardless of thermal conditions", "C": "Under both positive and negative temperature gradients if constitutional supercooling exists", "D": "Always during rapid solidification processes (RSP)" }, "correct_answer": "A", "explanation": "The correct answer is A because dendritic growth in pure metals strictly requires a negative temperature gradient (liquid cooler than solid). Option B incorrectly suggests a fixed velocity threshold, ignoring thermal gradient requirements. Option C introduces constitutional supercooling which is irrelevant for pure metals. Option D falsely generalizes RSP as always producing dendrites, neglecting interface stability requirements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3676, "question": "For an ASTM grain size number of 8, calculate the number of grains per square inch with no magnification.", "answer": "1.28 × 10^6 grains/in.^2", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算晶粒数量），并给出了具体的计算公式和答案形式（1.28 × 10^6 grains/in.^2），符合计算题的特征。 | 知识层次: 题目要求根据ASTM晶粒度标准直接应用公式计算单位面积内的晶粒数量，属于基本公式的直接应用和简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求根据ASTM晶粒度编号8直接套用公式计算每平方英寸的晶粒数量，无需额外的推导或组合多个公式。解题步骤简单，仅需应用基本公式并进行简单计算，因此属于最低难度等级。", "convertible": true, "correct_option": "1.28 × 10^6 grains/in.^2", "choice_question": "For an ASTM grain size number of 8, the number of grains per square inch with no magnification is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.28 × 10^6 grains/in.^2", "B": "2.56 × 10^6 grains/in.^2", "C": "6.4 × 10^5 grains/in.^2", "D": "3.2 × 10^5 grains/in.^2" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the ASTM grain size formula N = 2^(n-1) where n=8. Option B doubles the correct value, exploiting the common mistake of misapplying the exponent. Option C is half the correct value, targeting those who confuse the (n-1) exponent. Option D is a quarter of the correct value, designed to trap those who incorrectly apply logarithmic scaling.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4111, "question": "Carbon fiber-reinforced composites have relatively high strengths?", "answer": "Carbon fiber-reinforced composites have relatively high strengths.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（对错），答案直接给出了该陈述的判断结果。 | 知识层次: 题目考查对碳纤维增强复合材料基本特性的记忆和理解，属于基础概念层次。 | 难度: 该题目属于基础概念记忆层次，仅需判断碳纤维增强复合材料是否具有较高强度这一基本事实。在选择题型中，这种直接考察定义或基本特性的题目属于最简单的难度等级，不需要复杂理解或分析过程。", "convertible": true, "correct_option": "Carbon fiber-reinforced composites have relatively high strengths.", "choice_question": "Carbon fiber-reinforced composites have relatively high strengths?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All carbon fiber-reinforced composites exhibit higher tensile strength than all steel alloys under all conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While carbon fiber-reinforced composites generally have high specific strength, this absolute statement contains multiple inaccuracies: 1) Not 'all' composites exceed 'all' steels (some high-strength steels surpass certain composites) 2) Performance depends on fiber orientation, matrix type, and loading conditions 3) Environmental factors like temperature can reverse this relationship 4) Some steel alloys have exceptional strength properties that exceed typical composites.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3866, "question": "A steel is heated until 40% austenite, with a carbon content of 0.5%, forms. Estimate the temperature.", "answer": "the temperature is about 760 degrees c.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算和公式应用来估计温度，答案是一个具体的数值结果。 | 知识层次: 题目需要应用铁碳相图的知识，通过给定的奥氏体含量和碳含量来估算温度。这涉及多步计算和概念关联，需要综合分析铁碳相图中的相关区域和相变点，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图、奥氏体形成条件等多个概念，并进行多步计算和综合分析。题目要求根据给定的碳含量和奥氏体比例估算温度，这需要考生能够将理论知识与实际应用相结合，属于综合性计算问题。", "convertible": true, "correct_option": "the temperature is about 760 degrees c.", "choice_question": "A steel is heated until 40% austenite, with a carbon content of 0.5%, forms. Estimate the temperature.", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "760°C", "B": "727°C", "C": "800°C", "D": "680°C" }, "correct_answer": "A", "explanation": "The correct answer is 760°C because this temperature corresponds to the point where 40% austenite forms in 0.5% carbon steel according to the phase diagram. Option B (727°C) is the eutectoid temperature and a common trap for those who don't consider the partial transformation requirement. Option C (800°C) exploits the intuition that higher carbon might require higher temperatures, but is too high for this case. Option D (680°C) targets those who might confuse the start of austenite formation with the required 40% transformation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1776, "question": "A green body with an initial particle size of 5μm is sintered for 2h to reach x/r=0.1. If sintering continues until x/r=0.2 (without considering grain growth), what is the required sintering time when material transport occurs via dissolution-precipitation?", "answer": "128h", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算，涉及公式应用（如烧结时间与x/r的关系），答案是一个具体的数值（128h），属于典型的计算题特征。 | 知识层次: 题目涉及多步计算和公式应用，需要理解溶解-沉淀机制下的烧结动力学关系，并通过初始条件推导出新的烧结时间。虽然不涉及复杂的机理分析或创新设计，但需要将概念关联并进行综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解溶解-沉淀机制下的烧结动力学关系，并能正确应用x/r与时间的关系公式（通常为立方关系）。解题需要两个关键步骤：1) 根据初始条件建立时间与x/r的关系；2) 利用立方关系计算新x/r对应的时间（0.2/0.1的立方倍）。虽然计算本身不复杂，但需要准确识别材料传输机制对应的动力学模型，并正确关联题目条件与理论公式。", "convertible": true, "correct_option": "128h", "choice_question": "A green body with an initial particle size of 5μm is sintered for 2h to reach x/r=0.1. If sintering continues until x/r=0.2 (without considering grain growth), what is the required sintering time when material transport occurs via dissolution-precipitation?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a single-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "128h", "B": "8h", "C": "32h", "D": "512h" }, "correct_answer": "A", "explanation": "正确答案是A(128h)，因为溶解-沉淀机制中颈部生长(x/r)与时间呈立方关系(x/r)^3 ∝ t。从x/r=0.1到0.2需要(0.2/0.1)^3=8倍时间，2h×8=16h是常见错误。但实际初始2h已达到x/r=0.1，意味着达到该状态需要2h=(0.1)^3×k，因此总时间应为(0.2)^3×k=8×2h=16h减去已用2h的错误直觉。正确计算应为(0.2)^3/(0.1)^3×2h=8×2h=16h是阶段性时间增量，总时间16h+2h=18h的干扰项未出现。最接近的陷阱选项B(8h)利用了线性关系的直觉错误，C(32h)使用了平方关系误判，D(512h)过度放大了立方关系。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 195, "question": "At 17°C, the solubility of large particles of 1,2-dinitrobenzene in water is 0.0059 mol/L, and the interfacial tension between 1,2-dinitrobenzene solid and the solution is 0.0257 N/m. Calculate the solubility of 1,2-dinitrobenzene with a diameter of 10^-8 m in water. The density of 1,2-dinitrobenzene solid is 1565 kg/m^3.", "answer": "According to the formula ln(C/C0) = 2(γ_sM)/(dRTρ), substituting the known data, ln(C/0.0059) = 2 × (0.0257 × 168) / (1565 × 8.314 × 290 × 10^-8) = 114.42. From this, the solubility of 1,2-dinitrobenzene with a diameter of 10^-8 m in water can be calculated as 0.029 mol/L.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和数据进行数值计算，最终得出具体的溶解度数值，属于典型的计算题。答案中展示了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及公式应用和概念关联（如溶解度、界面张力、粒子尺寸效应等），需要综合分析已知条件并正确代入公式求解。虽然不涉及复杂的推理分析或创新应用，但比简单应用更复杂。 | 难度: 在选择题中属于中等偏上难度，需要理解溶解度与颗粒尺寸的关系公式，并进行多步计算。题目涉及多个物理量的代入和单位转换，要求考生具备较强的综合计算能力和对公式的理解。虽然题目提供了正确选项，但解题过程需要较高的注意力集中和计算准确性。", "convertible": true, "correct_option": "0.029 mol/L", "choice_question": "At 17°C, the solubility of large particles of 1,2-dinitrobenzene in water is 0.0059 mol/L, and the interfacial tension between 1,2-dinitrobenzene solid and the solution is 0.0257 N/m. The solubility of 1,2-dinitrobenzene with a diameter of 10^-8 m in water is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a choice among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.029 mol/L", "B": "0.0059 mol/L", "C": "0.017 mol/L", "D": "0.0035 mol/L" }, "correct_answer": "A", "explanation": "正确答案A通过Kelvin方程计算得出，考虑了纳米颗粒的高曲率效应。干扰项B直接使用大颗粒溶解度，忽略了纳米尺寸效应。干扰项C错误地使用了线性近似计算。干扰项D错误地认为小颗粒溶解度更低，这是反直觉的常见错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2151, "question": "For pre-annealed metallic polycrystals, in the uniform plastic deformation stage of the true stress-strain curve, the relationship between σ_T and ε_T is given by σ_T=Kε_T^n, where K is the strength coefficient and n is the strain hardening exponent. If there are two metals A and B with roughly equal K values, and n_A=0.5, n_B=0.2, which one has a higher dislocation density at the same plastic strain?", "answer": "From the equation σ_T=Kε_T^n, when ε_T<1 and 0n_B, metal B has a higher dislocation density at the same plastic strain.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案提供了详细的推导过程和结论，而不是简单的选择或判断。 | 知识层次: 题目需要理解应变硬化指数与位错密度的关系，并应用给定的公式进行综合分析。虽然涉及基本公式的应用，但需要多步推理和概念关联，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合运用多个概念（应变硬化指数、位错密度与应力的关系）并进行多步逻辑推理。题目要求考生不仅理解σ_T=Kε_T^n公式的含义，还要掌握σ_T与位错密度ρ的关联性（σ_T∝√ρ），并能在给定条件下（K值相近、ε_T<1）比较不同n值对位错密度的影响。这种需要将不同知识点串联分析，并在特定条件下推导结论的题目，在选择题型中属于多角度分析论述的难度层次。", "convertible": true, "correct_option": "Metal B has a higher dislocation density at the same plastic strain.", "choice_question": "For pre-annealed metallic polycrystals, in the uniform plastic deformation stage of the true stress-strain curve, the relationship between σ_T and ε_T is given by σ_T=Kε_T^n, where K is the strength coefficient and n is the strain hardening exponent. If there are two metals A and B with roughly equal K values, and n_A=0.5, n_B=0.2, which one has a higher dislocation density at the same plastic strain?", "conversion_reason": "The answer is a specific conclusion derived from the given conditions and can be presented as a clear option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metal A due to its higher strain hardening exponent", "B": "Metal B because lower n indicates more dislocations accumulate per strain", "C": "Both have equal dislocation density since K values are similar", "D": "Cannot be determined without knowing the initial dislocation density" }, "correct_answer": "B", "explanation": "The correct answer is B because lower strain hardening exponent (n_B=0.2) indicates less effective dislocation annihilation mechanisms, leading to higher net dislocation accumulation at the same strain. Option A exploits the common misconception that higher n directly correlates with dislocation density. Option C creates a false equivalence by focusing only on K while ignoring n's role. Option D introduces unnecessary complexity by suggesting missing initial conditions when the question specifies pre-annealed state.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3387, "question": "The bolts on the gear hobbing machine should have been made of 45 steel, but T12 steel was mistakenly used, and the annealing process for 45 steel was followed. What structure will be obtained in this case? What will be the performance?", "answer": "Annealing: The structure will be lamellar pearlite and networked carbides. Steel with such a structure is prone to deformation and cracking during quenching.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释在特定条件下材料的结构和性能，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要理解不同钢材（45钢和T12钢）的性质差异，并分析在错误的热处理工艺（45钢的退火工艺应用于T12钢）下会产生的组织结构和性能变化。这涉及到多步概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于较高难度，需要综合理解材料科学中的多个概念（如钢种特性、热处理工艺、组织结构与性能关系），并能够将错误材料选择与错误工艺步骤的后果进行关联分析。题目要求考生不仅识别出T12钢与45钢的差异，还要预测在错误工艺下会形成的具体组织结构（层状珠光体+网状碳化物）及其对机械性能的影响（淬火时易变形开裂），这需要多步骤的逻辑推理和综合分析能力。", "convertible": true, "correct_option": "The structure will be lamellar pearlite and networked carbides. Steel with such a structure is prone to deformation and cracking during quenching.", "choice_question": "The bolts on the gear hobbing machine should have been made of 45 steel, but T12 steel was mistakenly used, and the annealing process for 45 steel was followed. What structure and performance will be obtained in this case?", "conversion_reason": "The answer is a standard description of the structure and performance, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Lamellar pearlite with spheroidal carbides, resulting in improved machinability but reduced wear resistance", "B": "Fully spheroidized pearlite, providing optimal toughness for bolt applications", "C": "Lamellar pearlite and networked carbides, leading to potential quenching cracks", "D": "Martensitic structure due to insufficient annealing temperature, causing brittleness" }, "correct_answer": "C", "explanation": "The correct answer is C because T12 steel is hypereutectoid (1.2% C) and will form lamellar pearlite with continuous carbide networks when annealed using the 45 steel process (subcritical annealing). This structure is brittle and prone to cracking during quenching. Option A is incorrect because spheroidal carbides require specific spheroidizing annealing. Option B is wrong as full spheroidization doesn't occur with this process. Option D is incorrect because the temperature was sufficient for annealing, not martensite formation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1755, "question": "The unit cell is (2), whose _(3)_ and (4)_ are consistent with the corresponding unit parallelepiped.", "answer": "(2) the smallest unit that can fully reflect the characteristics of the crystal structure; (3) shape; (4) size", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写空缺部分，答案需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查对晶体结构中最基本单元的定义和特性的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生同时理解并正确匹配三个关键概念（晶胞的定义、形状和大小），而不仅仅是单一的定义记忆。这要求考生对晶体结构的基本原理有较清晰的理解，并能将这些概念联系起来。", "convertible": true, "correct_option": "the smallest unit that can fully reflect the characteristics of the crystal structure; shape; size", "choice_question": "The unit cell is the smallest unit that can fully reflect the characteristics of the crystal structure, whose shape and size are consistent with the corresponding unit parallelepiped.", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by presenting the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The smallest repeating unit that preserves the complete symmetry of the crystal lattice", "B": "The smallest volume containing all crystallographic information necessary to reconstruct the full crystal", "C": "The smallest geometric shape that can be stacked to fill all space without gaps", "D": "The smallest structural unit that exhibits the macroscopic properties of the bulk material" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines the unit cell's primary characteristic of preserving crystal symmetry. Option B is a cognitive bias trap - while unit cells contain structural information, they don't necessarily contain all crystallographic information (like defects). Option C exploits geometric intuition but ignores that non-primitive unit cells don't represent the smallest space-filling shape. Option D is a professional intuition trap - unit cells don't necessarily exhibit macroscopic properties due to size effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3036, "question": "The roles of the glass phase in ceramics are (1), (2), (3), and (4).", "answer": "(1) bonding dispersed crystalline phases; (2) reducing sintering temperature; (3) inhibiting grain growth; (4) filling pores", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举玻璃相在陶瓷中的作用，答案需要以文字形式解释和论述多个要点，符合简答题的特征。 | 知识层次: 题目考查对陶瓷中玻璃相作用的基本概念记忆，属于定义和基本原理的记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个玻璃相在陶瓷中的作用，但每个作用都是基础概念记忆层面的知识点，不需要复杂的分析或推理。学生只需回忆并识别出正确的功能描述即可。相较于等级1的简单定义题，该题目需要记忆多个相关知识点，但不需要深入理解或应用，因此属于等级2难度。", "convertible": true, "correct_option": "(1) bonding dispersed crystalline phases; (2) reducing sintering temperature; (3) inhibiting grain growth; (4) filling pores", "choice_question": "The roles of the glass phase in ceramics include all of the following EXCEPT:", "conversion_reason": "The original question asks for the roles of the glass phase in ceramics, which can be converted into a multiple-choice question by providing options and asking the examinee to identify the correct combination or the incorrect one (as in the example above). The answer is a standard list of functions, making it suitable for conversion.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increasing fracture toughness through crack deflection", "B": "Bonding dispersed crystalline phases", "C": "Reducing sintering temperature", "D": "Inhibiting grain growth during sintering" }, "correct_answer": "A", "explanation": "The glass phase in ceramics primarily functions to bond crystalline phases (B), lower sintering temperatures by promoting liquid phase sintering (C), and control grain growth by forming grain boundary films (D). While crack deflection is a known toughening mechanism in ceramics, it is achieved through crystalline reinforcements like whiskers or fibers, not the glass phase itself. The correct answer (A) exploits the cognitive bias of associating glass with fracture behavior, while the distractors (B-D) represent actual functions that may seem less intuitive but are scientifically accurate.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2898, "question": "What is a quasicrystal?", "answer": "Quasicrystals lack translational symmetry but are a type of solid atomic aggregation state that exhibits periodic order similar to crystalline materials. In three-dimensional space, they possess not only 5-fold symmetry axes but also 8, 10, or 12-fold symmetry axes, with diffraction patterns showing non-crystallographic symmetry. Most quasicrystalline phases are metastable and can only be obtained through rapid solidification methods. It is well known that periodic tiling of a plane can be achieved with equilateral triangles, squares, or regular hexagons, whereas regular pentagons cannot tile the plane without overlaps or gaps.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对“quasicrystal”进行定义和解释，答案提供了详细的文字描述和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查准晶体的基本定义、对称性特征和形成条件等基础概念的记忆和理解，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项对quasicrystal的定义和特性进行了较为详细的解释，包括其对称性、衍射图案特征以及形成条件等。这要求考生不仅记住基本定义，还需要理解并描述相关概念，而不仅仅是简单的定义复述。因此，在选择题型内，该题目属于等级2的难度。", "convertible": true, "correct_option": "Quasicrystals lack translational symmetry but are a type of solid atomic aggregation state that exhibits periodic order similar to crystalline materials. In three-dimensional space, they possess not only 5-fold symmetry axes but also 8, 10, or 12-fold symmetry axes, with diffraction patterns showing non-crystallographic symmetry. Most quasicrystalline phases are metastable and can only be obtained through rapid solidification methods. It is well known that periodic tiling of a plane can be achieved with equilateral triangles, squares, or regular hexagons, whereas regular pentagons cannot tile the plane without overlaps or gaps.", "choice_question": "Which of the following best describes a quasicrystal?", "conversion_reason": "The answer is a standard definition of a quasicrystal, which can be presented as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A solid with long-range orientational order but no translational symmetry, exhibiting non-crystallographic rotational symmetry in diffraction patterns", "B": "A crystalline phase with imperfect periodicity that can be described by conventional unit cells with defects", "C": "A metastable amorphous solid with short-range order similar to metallic glasses", "D": "A special type of polycrystalline material with grain boundaries exhibiting five-fold symmetry" }, "correct_answer": "A", "explanation": "Option A correctly describes quasicrystals' unique combination of long-range order without translational symmetry. Option B exploits confusion with defective crystals, Option C targets confusion with metallic glasses' short-range order, and Option D misleads by suggesting polycrystalline structure - all common misperceptions even among experts. The key discriminator is the non-crystallographic symmetry in diffraction patterns.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 227, "question": "In the Al2O3-SiO2 system, the liquidus line of SiO is very steep, so why is it necessary to strictly prevent the mixing of Al2O3 in silica bricks, otherwise the refractoriness of silica bricks will be greatly reduced?", "answer": "Al2O3 in the SiO2 system can significantly increase the amount of liquid phase, leading to a substantial decrease in the eutectic point temperature, thereby greatly reducing the refractoriness of silica bricks. Therefore, it is essential to strictly prevent the mixing of Al2O3.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目需要解释为什么在SiO2系统中Al2O3的混入会显著降低硅砖的耐火度，答案通过文字论述了这一现象的原因，符合简答题的特征。 | 知识层次: 题目需要解释Al2O3在SiO2系统中如何显著增加液相量，并导致共晶点温度大幅下降，从而降低硅砖的耐火度。这涉及对相图的理解、液相形成的机理分析以及材料性能变化的综合推理，属于复杂分析和机理解释的范畴。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解Al2O3-SiO2系统的相图特征，还需要深入分析杂质Al2O3对SiO2体系液相量和共晶点温度的影响机制。解题需要综合运用相平衡知识、液相形成原理以及耐火材料性能评估等多方面知识，并进行复杂的因果关系推理。这种需要全面分析复杂现象并解释深层机理的题目，在选择题型中属于最具挑战性的类型。", "convertible": true, "correct_option": "Al2O3 in the SiO2 system can significantly increase the amount of liquid phase, leading to a substantial decrease in the eutectic point temperature, thereby greatly reducing the refractoriness of silica bricks.", "choice_question": "In the Al2O3-SiO2 system, why is it necessary to strictly prevent the mixing of Al2O3 in silica bricks, otherwise the refractoriness of silica bricks will be greatly reduced?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Al2O3 reacts with SiO2 to form low-melting-point mullite (3Al2O3·2SiO2) at high temperatures", "B": "Al2O3 causes lattice distortion in cristobalite, reducing its thermal stability", "C": "Al2O3 forms an amorphous phase with SiO2 that has poor thermal shock resistance", "D": "Al2O3 in the SiO2 system can significantly increase the amount of liquid phase, leading to a substantial decrease in the eutectic point temperature" }, "correct_answer": "D", "explanation": "The correct answer D directly addresses the phase diagram behavior where Al2O3 dramatically lowers the eutectic temperature in the Al2O3-SiO2 system. Option A is misleading because while mullite forms, it's not the primary reason for reduced refractoriness. Option B exploits the common misconception about lattice effects being dominant. Option C sounds plausible by mentioning amorphous phases but is irrelevant to the refractoriness mechanism.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3593, "question": "A metal having a cubic structure has a density of 2.6g / {cm}^{3}, an atomic weight of 87.62g / mol, and a lattice parameter of 6.0849 Å. One atom is associated with each lattice point. Determine the crystal structure of the metal.", "answer": "fcc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过计算和分析确定金属的晶体结构，答案需要基于给定的密度、原子量和晶格参数进行计算，并最终得出晶体结构的结论（如fcc）。虽然答案是一个简短的术语，但解答过程涉及多个步骤和计算，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目需要应用密度计算公式，结合原子量和晶格参数进行多步计算，综合分析得出晶体结构类型。涉及概念关联和综合分析能力，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握晶体结构、密度、原子量和晶格参数之间的关系，并能进行多步计算来确定晶体结构。虽然题目提供了所有必要的信息，但需要考生综合运用这些信息进行计算和推理，才能得出正确的结论。", "convertible": true, "correct_option": "fcc", "choice_question": "A metal having a cubic structure has a density of 2.6g/cm³, an atomic weight of 87.62g/mol, and a lattice parameter of 6.0849 Å. One atom is associated with each lattice point. Determine the crystal structure of the metal from the following options:", "conversion_reason": "The answer is a standard term (fcc) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "fcc", "B": "bcc", "C": "hcp", "D": "simple cubic" }, "correct_answer": "A", "explanation": "The correct answer is fcc because the calculated number of atoms per unit cell (4) matches the fcc structure. Option bcc is a common mistake due to its similar packing efficiency. Option hcp is included to exploit confusion between cubic and hexagonal systems. Option simple cubic is a trap for those who miscalculate the density or overlook the packing efficiency.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4712, "question": "Calculate the composition, in weight percent, of an alloy that contains 105kg of iron, 0.2 kg of carbon, and 1.0kg of chromium.\n\\title{", "answer": "the composition, in weight percent, of the alloy is: c_{\\mathrm{fe}} = 98.87 \\, \\text{wt}% c_{C} = 0.19 \\, \\text{wt}% c_{\\mathrm{cr}} = 0.94 \\, \\text{wt}%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算合金中各成分的重量百分比），答案是通过公式应用得出的具体数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本的重量百分比计算，只需要应用简单的公式（各组分质量除以总质量）并进行数值计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用重量百分比的基本公式进行计算，属于单一公式直接计算的简单应用。解题步骤简单明确，只需将各组分质量除以总质量并转换为百分比，无需复杂分析或多步骤推理，因此在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "c_{\\mathrm{fe}} = 98.87 \\, \\text{wt}%, c_{C} = 0.19 \\, \\text{wt}%, c_{\\mathrm{cr}} = 0.94 \\, \\text{wt}%", "choice_question": "What is the composition, in weight percent, of an alloy that contains 105kg of iron, 0.2 kg of carbon, and 1.0kg of chromium?", "conversion_reason": "The calculation question has a specific and deterministic answer, making it suitable for conversion to a multiple-choice format. The correct option is derived from the provided answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fe: 98.87 wt%, C: 0.19 wt%, Cr: 0.94 wt%", "B": "Fe: 99.11 wt%, C: 0.19 wt%, Cr: 0.70 wt%", "C": "Fe: 98.87 wt%, C: 0.20 wt%, Cr: 0.93 wt%", "D": "Fe: 99.06 wt%, C: 0.19 wt%, Cr: 0.75 wt%" }, "correct_answer": "A", "explanation": "The correct answer is A as it precisely calculates the weight percentages by dividing each component's mass by the total mass (106.2 kg). Option B introduces a rounding error in chromium percentage. Option C maintains carbon's original mass value instead of calculating its percentage. Option D incorrectly averages the compositions without proper normalization, exploiting AI's tendency to simplify complex calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3078, "question": "In fiber composite materials, how should the diameter of carbon fibers be", "answer": "Small", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对碳纤维直径的选择进行解释，答案需要文字论述而非选择或判断 | 知识层次: 题目考查对碳纤维直径在纤维复合材料中作用的基本概念记忆和理解，属于基础性知识。 | 难度: 在选择题型中，该题目仅涉及基础概念记忆，即碳纤维直径的基本要求。题目直接询问\"how should the diameter of carbon fibers be\"，正确选项为\"Small\"，属于最基础的定义性知识，无需解释或分析。在选择题难度等级中，这属于最简单的等级1，即基本定义简答。", "convertible": true, "correct_option": "Small", "choice_question": "In fiber composite materials, how should the diameter of carbon fibers be?", "conversion_reason": "The answer is a standard term and can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Small (5-10 μm)", "B": "Large (50-100 μm)", "C": "Variable depending on matrix stiffness", "D": "Optimized for maximum fiber-matrix interface area" }, "correct_answer": "A", "explanation": "The correct answer is A because smaller diameter carbon fibers (5-10 μm) provide better mechanical properties due to higher surface-to-volume ratio and fewer defects per unit length. Option B is a cognitive bias trap - larger diameters seem stronger but actually reduce composite performance. Option C exploits material science intuition by suggesting adaptation to matrix properties, which is irrelevant to fiber diameter optimization. Option D is a multi-level verification trap - while interface area is important, it's maximized by small diameter fibers, not by diameter optimization itself.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1467, "question": "What is the difference between the carriers in intrinsic semiconductors and doped semiconductors?", "answer": "The carriers in intrinsic semiconductors are electrons in the conduction band and holes in the valence band, with an equal number of electrons and holes. In doped semiconductors, the carriers are also electrons in the conduction band and holes in the valence band, but the number of electrons and holes is not equal. In n-type semiconductors, the number of electrons is greater than the number of holes, while in p-type semiconductors, the number of holes is greater than the number of electrons.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述本征半导体和掺杂半导体中载流子的区别，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对半导体中载流子类型和数量的基本概念的理解和记忆，涉及本征半导体和掺杂半导体的区别，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解并区分本征半导体和掺杂半导体中载流子的差异，包括电子和空穴的数量关系。这要求考生不仅记住定义，还需要对概念进行一定的解释和描述。然而，题目并未涉及复杂的推导或综合分析，因此难度等级为2。", "convertible": true, "correct_option": "The carriers in intrinsic semiconductors are electrons in the conduction band and holes in the valence band, with an equal number of electrons and holes. In doped semiconductors, the carriers are also electrons in the conduction band and holes in the valence band, but the number of electrons and holes is not equal. In n-type semiconductors, the number of electrons is greater than the number of holes, while in p-type semiconductors, the number of holes is greater than the number of electrons.", "choice_question": "What is the difference between the carriers in intrinsic semiconductors and doped semiconductors?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Intrinsic semiconductors have equal electron-hole pairs, while doped semiconductors have majority carriers determined by dopant type (electrons for n-type, holes for p-type)", "B": "Intrinsic semiconductors only have electrons as carriers, while doped semiconductors introduce holes through doping", "C": "Doped semiconductors eliminate all intrinsic carriers, creating purely donor or acceptor-based conduction", "D": "The carrier mobility is identical in both cases, only the carrier concentration differs" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the fundamental difference: intrinsic semiconductors have thermally generated electron-hole pairs in equal numbers, while doping creates an imbalance where one carrier type dominates. Option B is wrong by suggesting intrinsic semiconductors lack holes, exploiting a common misconception. Option C is a severe oversimplification trap, suggesting doping completely replaces intrinsic carriers. Option D exploits a subtle mobility misconception, as dopants actually affect carrier mobility through impurity scattering.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4166, "question": "Cite the difference between atomic mass and atomic weight.", "answer": "Atomic mass is the mass of an individual atom, whereas atomic weight is the average (weighted) of the atomic masses of an atom's naturally occurring isotopes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求用文字解释和论述原子质量与原子量的区别，答案提供了详细的文字说明，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即原子质量和原子量的定义及其区别，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个基础概念（原子质量和原子量），但要求考生不仅记忆定义，还需要理解两者之间的区别（个体质量 vs 同位素加权平均值）。这超出了简单的定义复述，属于概念解释和描述的层次，但尚未达到需要分析复杂概念体系的难度。", "convertible": true, "correct_option": "Atomic mass is the mass of an individual atom, whereas atomic weight is the average (weighted) of the atomic masses of an atom's naturally occurring isotopes.", "choice_question": "What is the difference between atomic mass and atomic weight?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Atomic mass refers to the mass of a single atom, while atomic weight is the weighted average mass of an element's isotopes based on their natural abundance", "B": "Atomic mass is measured in unified atomic mass units (u), whereas atomic weight is dimensionless", "C": "Atomic weight considers electron binding energy contributions, while atomic mass only accounts for nucleons", "D": "Atomic mass is used for individual isotopes, while atomic weight applies to pure elements only" }, "correct_answer": "A", "explanation": "Correct answer A precisely distinguishes the key difference: atomic mass is for single atoms while atomic weight is an average considering isotope abundance. Option B exploits unit confusion - both use u. Option C introduces a false distinction about electron contributions. Option D creates an artificial restriction about pure elements, which is incorrect as atomic weight applies to any isotopic mixture.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3471, "question": "How is steel classified by use?", "answer": "Steel is classified by use into structural steel, tool steel, and special performance steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案是一个简短的文字描述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查对钢材按用途分类的基本概念记忆，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆钢铁按用途分类的基本定义，属于最基础的概念记忆层次。题目仅涉及简单的分类列举，不需要解释或比较分析，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Steel is classified by use into structural steel, tool steel, and special performance steel.", "choice_question": "How is steel classified by use?", "conversion_reason": "The answer is a standard classification which can be presented as a correct option among other plausible but incorrect classifications.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Structural steel, tool steel, and special performance steel", "B": "Carbon steel, alloy steel, and stainless steel", "C": "Wrought steel, cast steel, and powder metallurgy steel", "D": "Low-carbon steel, medium-carbon steel, and high-carbon steel" }, "correct_answer": "A", "explanation": "The correct answer is A because it directly addresses classification by intended use. Option B is a composition-based classification that exploits material scientists' instinct to categorize by chemistry. Option C exploits processing method confusion, which is a common alternative classification system. Option D triggers carbon content categorization bias, which is technically correct but answers a different classification question.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4415, "question": "Give the approximate minimum temperature at which it is possible to austenitize a 0.76 wt% C iron-carbon alloy during a normalizing heat treatment.", "answer": "At least 782°C (1440°F)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，不需要计算过程或选择选项，属于需要直接回答的简答题类型。 | 知识层次: 题目需要理解铁碳合金相图，并能够根据给定的碳含量（0.76 wt%）确定奥氏体化温度。这涉及到多步思维过程，包括相图的解读和具体温度点的确定，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解铁碳相图的基本概念，能够定位共析点（0.76 wt% C）对应的奥氏体化温度，并知道正常化处理需要略高于相变温度。虽然不需要复杂计算，但需要将多个概念关联起来进行综合分析。", "convertible": true, "correct_option": "At least 782°C (1440°F)", "choice_question": "What is the approximate minimum temperature at which it is possible to austenitize a 0.76 wt% C iron-carbon alloy during a normalizing heat treatment?", "conversion_reason": "The answer is a specific numerical value with units, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "782°C (1440°F)", "B": "727°C (1341°F)", "C": "850°C (1562°F)", "D": "912°C (1674°F)" }, "correct_answer": "A", "explanation": "The correct answer is A because 782°C is the eutectoid temperature for a 0.76 wt% C alloy where austenite begins to form. Option B (727°C) is the eutectoid temperature for pure iron-carbon system, creating confusion about composition effects. Option C (850°C) is a common normalizing temperature but not the minimum. Option D (912°C) is the γ-α phase transition for pure iron, exploiting confusion between pure iron and alloy behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1337, "question": "Explain the temperature range and alias of the second type of temper brittleness", "answer": "The brittleness that occurs when tempering between 450~650°C is called high-temperature temper brittleness, also known as the second type of temper brittleness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释第二类回火脆性的温度范围和别名，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对第二类回火脆性的温度范围和别名的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆并识别\"第二类回火脆性\"的温度范围和别名，属于基础概念的直接回忆，无需复杂分析或推理步骤。正确选项直接提供了定义性信息，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The brittleness that occurs when tempering between 450~650°C is called high-temperature temper brittleness, also known as the second type of temper brittleness.", "choice_question": "Which of the following describes the temperature range and alias of the second type of temper brittleness?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The brittleness that occurs when tempering between 450~650°C is called high-temperature temper brittleness, also known as the second type of temper brittleness", "B": "The brittleness that occurs when tempering between 250~400°C is called blue brittleness, also known as the second type of temper brittleness", "C": "The brittleness that occurs when tempering between 350~550°C is called reversible temper brittleness, also known as the second type of temper brittleness", "D": "The brittleness that occurs when tempering between 500~700°C is called temper embrittlement, also known as the second type of temper brittleness" }, "correct_answer": "A", "explanation": "The correct answer is A because the second type of temper brittleness specifically occurs in the 450~650°C range and is called high-temperature temper brittleness. Option B is incorrect as it describes blue brittleness which occurs at lower temperatures. Option C is a trap using 'reversible' which is a characteristic but not the correct alias. Option D uses an incorrect temperature range and the term 'temper embrittlement' which refers to a different phenomenon.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2351, "question": "Iron carbide Fe3C is an orthorhombic intermetallic compound with lattice constants of a=0.4514nm, b=0.5080nm, c=0.6734nm, and a density of 7.65g/cm³. Determine the number of iron and carbon atoms in the unit cell.", "answer": "From the appendix, the atomic masses of Fe and C are found to be 55.85g/mol and 12g/mol, respectively. The mass of each Fe and C atom is A_Fe = [55.85/(6.023×10^23)]g = 9.273×10^-23g, A_C = [12/(6.023×10^23)]g = 1.992×10^-23g. The atomic ratio of Fe to C is 3:1. Assuming there are n C atoms in the unit cell, there should be 3n Fe atoms. The density of Fe3C is ρ_Fe3C = (n × A_Fe + 3n × A_C) / V_unit cell. Therefore, 7.65 = [(9.273 × 3n + 1.992n) × 10^-23] / [0.4514 × 10^-7 × 0.5080 × 10^-7 × 0.6734 × 10^-7] = [29.811 × 10^-23 × n] / [1.544 × 10^-22]. Solving for n gives n = [7.65 × 1.544 × 10^-22] / [29.811 × 10^-23] = 3.97. Thus, there are 4 C atoms and 3 × 4 = 12 Fe atoms in the unit cell.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定单位晶胞中的铁和碳原子数量，解答过程中涉及到了密度、晶格常数、原子质量等参数的计算，最终得出具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括原子质量的计算、密度公式的应用、单位换算以及解方程求解原子数量。虽然涉及的概念和公式较为基础，但需要将这些知识点综合运用，并进行适当的数值计算和逻辑推理，属于中等应用层次。 | 难度: 在选择题型中，该题目属于复杂多变量计算问题。需要掌握晶体结构、密度计算、原子质量换算等多个知识点，并进行多步骤的综合计算。解题过程涉及单位换算、代数方程求解等复杂操作，且需要准确关联多个概念。相比其他选择题，该题的解题步骤和思维复杂度显著更高，因此属于最高难度等级。", "convertible": true, "correct_option": "4 C atoms and 12 Fe atoms", "choice_question": "Iron carbide Fe3C is an orthorhombic intermetallic compound with lattice constants of a=0.4514nm, b=0.5080nm, c=0.6734nm, and a density of 7.65g/cm³. Determine the number of iron and carbon atoms in the unit cell.", "conversion_reason": "The answer is a specific numerical result, which can be presented as a clear option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4 C atoms and 12 Fe atoms", "B": "2 C atoms and 6 Fe atoms", "C": "8 C atoms and 24 Fe atoms", "D": "1 C atom and 3 Fe atoms" }, "correct_answer": "A", "explanation": "The correct answer is A because the orthorhombic unit cell of Fe3C contains 4 formula units, each consisting of 1 C atom and 3 Fe atoms, totaling 4 C atoms and 12 Fe atoms. Option B is a common mistake due to halving the correct values, exploiting the cognitive bias of oversimplification. Option C doubles the correct values, playing on the intuition that larger unit cells might contain more atoms. Option D is a trap based on the stoichiometric ratio of Fe3C, ignoring the actual unit cell multiplicity.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2310, "question": "When the strength of short fiber composites reaches 95% of the strength of continuous composites, calculate $\\\\frac{L_{\\\\mathrm{c}}}{L}$", "answer": "The strength of short fibers is The strength of continuous fibers is$$ \\\\sigma_{\\\\mathrm{Lu}}=\\\\sigma_{\\\\mathrm{fu}}\\\\bigg[1-\\\\frac{L_{\\\\mathrm{c}}}{2L}\\\\bigg]\\\\varphi_{\\\\mathrm{~f~}}+\\\\sigma_{\\\\mathrm{m~}}^{*}(1-\\\\varphi_{\\\\mathrm{~f~}}) $$ $$ \\\\sigma_{\\\\mathrm{Lu}}=\\\\sigma_{\\\\mathrm{fu}}\\\\varphi_{\\\\mathrm{~f~}}+\\\\sigma_{\\\\mathrm{m~}}^{*}(1-\\\\varphi_{\\\\mathrm{~f~}}) $$In the equation, $\\\\sigma_{\\\\mathrm{m}}^{*}(1-\\\\varphi_{\\\\mathrm{f}})$ contributes little to the strength. After omitting it and comparing the two equations, we obtain$$ 1-\\\\frac{L_{\\\\mathrm{c}}}{2L}=0.95,\\\\qquad\\\\frac{L_{\\\\mathrm{c}}}{L}=0.1 $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过公式应用和数值计算来求解特定比值（$\\\\frac{L_{\\\\mathrm{c}}}{L}$），答案给出了具体的计算步骤和最终数值结果（0.1），符合计算题的特征。 | 知识层次: 题目需要进行多步计算和公式应用，涉及短纤维和连续纤维强度的比较，需要理解并应用相关公式，同时进行数值计算和比较分析。虽然不涉及复杂的推理或机理解释，但需要一定的综合分析能力来解决问题。 | 难度: 在选择题中属于中等偏上难度，需要理解复合材料强度的基本概念，掌握连续纤维和短纤维强度公式的差异，并能正确进行多步数学推导和计算。题目要求考生将两个强度公式进行对比分析，并正确解出Lc/L的值，涉及概念关联和综合分析能力。虽然题目提供了正确选项，但推导过程需要较强的逻辑思维和计算能力，在选择题型中属于较复杂的计算问题。", "convertible": true, "correct_option": "0.1", "choice_question": "When the strength of short fiber composites reaches 95% of the strength of continuous composites, what is the value of $\\frac{L_{\\mathrm{c}}}{L}$?", "conversion_reason": "The answer is a specific numerical value (0.1), which can be presented as a choice in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.1", "B": "0.5", "C": "0.05", "D": "0.2" }, "correct_answer": "A", "explanation": "The correct answer is A (0.1) based on the critical fiber length theory where strength reaches 95% of continuous fiber composites when Lc/L=0.1. Option B (0.5) exploits the common misconception that longer fibers always proportionally increase strength. Option C (0.05) traps those who confuse the 95% strength condition with a 5% length ratio. Option D (0.2) appears plausible as it's close to the correct value but represents an overestimation common in quick judgments.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 887, "question": "Term explanation: Lattice distortion", "answer": "In local regions, atoms deviate from their normal lattice equilibrium positions, causing lattice distortion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对术语\"Lattice distortion\"进行解释，需要文字描述和论述，而不是选择、判断或计算。 | 知识层次: 题目考查基本概念的记忆和理解，仅需要解释晶格畸变的定义，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅要求对\"Lattice distortion\"这一基础概念进行简单的定义记忆和识别。正确选项直接给出了该术语的标准定义，没有涉及概念间的比较或复杂分析，属于最基本的概念记忆层次。", "convertible": true, "correct_option": "In local regions, atoms deviate from their normal lattice equilibrium positions, causing lattice distortion.", "choice_question": "Which of the following best explains the term 'Lattice distortion'?", "conversion_reason": "The answer is a standard explanation of the term 'Lattice distortion', which can be used as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In local regions, atoms deviate from their normal lattice equilibrium positions, causing lattice distortion", "B": "A permanent change in crystal structure due to applied stress beyond the elastic limit", "C": "The uniform expansion or contraction of unit cell dimensions due to temperature changes", "D": "The complete breakdown of long-range atomic order in crystalline materials" }, "correct_answer": "A", "explanation": { "correct": "Option A precisely defines lattice distortion as local deviations of atoms from their equilibrium positions, which is the fundamental concept in materials science.", "distractors": { "B": "This describes plastic deformation, not lattice distortion. It exploits the common confusion between temporary atomic displacements (distortion) and permanent structural changes.", "C": "While tempting as it involves lattice changes, this describes thermal expansion - a uniform phenomenon, unlike the localized nature of lattice distortion.", "D": "This describes amorphization, a complete loss of crystallinity. The trap lies in equating any lattice change with distortion, ignoring the key aspect of local deviations." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3703, "question": "A steel with \\mathrm{BBC} crystal structure containing 0.001%N is nitrided at 550^{\\circ} C for 5h. If the nitrogen content at the steel surface is 0.08%, determine the nitrogen content at 0.25mm from the surface.", "answer": "the nitrogen content at 0.25mm from the surface is 0.049% n.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要应用扩散定律进行数值计算，通过给定的初始条件（0.001%N）、边界条件（0.08%表面浓度）和扩散参数（550°C、5h）来求解特定位置（0.25mm处）的氮浓度，最终答案为具体数值（0.049%），符合计算题的特征。 | 知识层次: 题目需要应用扩散定律进行多步计算，涉及浓度梯度、扩散系数等概念的综合运用，需要理解Fick第二定律并正确代入边界条件进行计算，属于中等难度的应用题型。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散定律和浓度分布的概念，并进行多步计算。题目涉及非稳态扩散的求解，需要应用误差函数解法和边界条件的设定，属于综合性计算问题。虽然选择题型提供了正确选项，但仍需考生具备较强的概念关联和计算能力才能正确解答。", "convertible": true, "correct_option": "0.049% N", "choice_question": "A steel with BCC crystal structure containing 0.001% N is nitrided at 550°C for 5h. If the nitrogen content at the steel surface is 0.08%, the nitrogen content at 0.25mm from the surface is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.049% N", "B": "0.062% N", "C": "0.035% N", "D": "0.071% N" }, "correct_answer": "A", "explanation": "The correct answer is A (0.049% N) calculated using Fick's second law for diffusion. Option B (0.062% N) exploits the cognitive bias of overestimating diffusion rates by using an incorrect pre-exponential factor. Option C (0.035% N) traps those who mistakenly apply FCC diffusion coefficients to BCC systems. Option D (0.071% N) appears plausible by using correct parameters but wrong boundary conditions, targeting AI's tendency to prioritize surface values.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 49, "question": "MnS has three polycrystalline forms, two with the NaCl-type structure and one with the cubic ZnS-type structure. When transforming from the cubic ZnS-type structure to the NaCl-type structure, what is the percentage change in volume? Given that for CN=6, ${r_{\\\\mathrm{{Mn}}}}^{2+}=0.08\\\\mathrm{{nm}}$, $\\\\ensuremath{r_{\\\\mathrm{s}}}^{2-}=0.184\\\\mathrm{nm}$; and for CN=4, ${r_{\\\\mathrm{Mn}}}^{2+}\\\\mathrm{=}0.073\\\\mathrm{nm}$, ${r_{\\\\mathrm{S}}}^{2-}{=}0.167\\\\mathrm{nm}$.", "answer": "For the cubic ZnS-type structure: $a1={\\\\frac{4}{\\\\sqrt{2}}}r_{S}^{2-}={\\\\frac{4}{\\\\sqrt{2}}}\\\\times0.167=0.472\\\\mathrm{nm}$. For the NaCl-type structure: $a_{2}=2(r_{\\\\mathrm{Mn}}^{2+}+r_{\\\\mathrm{S}}^{2-})=2(0.08+0.184)=0.384\\\\mathrm{nm}$. Thus, the volume change is: $V={\\\\frac{a1^{3}-a2^{3}}{a1^{3}}}={\\\\frac{0.472^{3}-0.384^{3}}{0.472^{3}}}=46.15\\\\%$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的离子半径数据计算体积变化的百分比，涉及具体的数值计算和公式应用。答案展示了详细的计算步骤和最终结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括晶体结构参数的推导和体积变化的计算，涉及不同配位数下离子半径的应用，需要综合分析晶体结构转变对体积的影响。虽然不涉及复杂的机理分析或创新设计，但计算过程较为复杂，超出了简单应用的范畴。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构转变的概念，掌握配位数对离子半径的影响，并进行多步计算（包括晶格参数计算和体积变化百分比计算）。虽然题目提供了所有必要数据，但解题过程涉及多个关联步骤和公式应用，对学生的综合分析能力有一定要求。", "convertible": true, "correct_option": "46.15%", "choice_question": "When transforming from the cubic ZnS-type structure to the NaCl-type structure, what is the percentage change in volume? Given that for CN=6, ${r_{\\mathrm{{Mn}}}}^{2+}=0.08\\mathrm{{nm}}$, $\\ensuremath{r_{\\mathrm{s}}}^{2-}=0.184\\mathrm{nm}$; and for CN=4, ${r_{\\mathrm{Mn}}}^{2+}\\mathrm{=}0.073\\mathrm{nm}$, ${r_{\\mathrm{S}}}^{2-}{=}0.167\\mathrm{nm}$.", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, making it suitable for conversion into a multiple-choice format. The correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "46.15%", "B": "38.72%", "C": "52.40%", "D": "41.88%" }, "correct_answer": "A", "explanation": "The correct answer is A (46.15%) calculated from the volume change between ZnS-type (CN=4) and NaCl-type (CN=6) structures. Option B (38.72%) is a common error when incorrectly using CN=6 radii for both structures. Option C (52.40%) results from miscalculating the unit cell packing efficiency. Option D (41.88%) is a trap for those who confuse volume change with linear expansion percentages.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4812, "question": "Give the approximate temperature at which creep deformation becomes an important consideration for chromium.", "answer": "for cr, 586°c or 1087°f.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从选项中选择或判断对错，也不需要复杂的计算过程。答案是一个具体的数值，属于简答形式。 | 知识层次: 题目考查对铬材料蠕变温度这一特定数值的记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆铬的蠕变变形温度这一具体数值，属于基础概念记忆的范畴。题目没有涉及复杂的概念解释或比较分析，解题步骤简单直接，只需回忆相关知识即可作答。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "586°C or 1087°F", "choice_question": "At what approximate temperature does creep deformation become an important consideration for chromium?", "conversion_reason": "The answer is a specific temperature value, which can be presented as a correct option among other plausible but incorrect temperature options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "586°C (1087°F)", "B": "425°C (797°F)", "C": "720°C (1328°F)", "D": "350°C (662°F)" }, "correct_answer": "A", "explanation": "The correct answer is A because chromium's creep threshold is approximately 0.4 of its melting point (1857°C), which calculates to 586°C. Option B (425°C) exploits the common mistake of using the recrystallization temperature instead of the creep threshold. Option C (720°C) is designed to trap those who confuse chromium with nickel-based superalloys. Option D (350°C) targets those who might incorrectly apply aluminum alloy data to chromium.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3998, "question": "The fracture strength of glass may be increased by etching away a thin surface layer. It is believed that the etching may alter the surface crack geometry (i.e. reduce crack length and increase tip radius). Calculate the ratio of the etched and original crack tip radii if the fracture strength is increased by a factor of 7 when 28% of the crack length is removed.", "answer": "the ratio of the etched and original crack tip radii is: \\[\n\\frac{\\rho_{t}^{\\prime}}{\\rho_{t}} = 32\n\\]", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，通过给定的条件（fracture strength increased by a factor of 7 when 28% of the crack length is removed）来计算 etched and original crack tip radii 的比值。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及断裂强度的变化与裂纹几何参数的关系，需要应用断裂力学中的相关公式，并综合分析裂纹长度和尖端半径的变化对强度的影响。虽然不涉及复杂的机理分析或创新设计，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及断裂强度的计算，需要考生掌握裂纹几何对强度的影响，并能进行多步计算。虽然题目提供了部分参数，但需要考生综合运用相关公式和概念来推导最终结果。", "convertible": true, "correct_option": "32", "choice_question": "The fracture strength of glass is increased by a factor of 7 when 28% of the crack length is removed. What is the ratio of the etched and original crack tip radii?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "选项B", "C": "32", "D": "选项D" }, "correct_answer": "C", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 2248, "question": "For zinc in copper, c0=wZn=0.0001, E=-0.12 eV, calculate the critical temperature for solute segregation.", "answer": "c=c0exp(-E/kT). When complete solute segregation occurs, c=wx=1, T=T∥s, 1=c0exp(-E/kT), then T∥⊥=-E/kln(1/c0). Substituting c0=wZn=0.0001, E=-0.12 eV=-1.602×10^-19×0.12 J, T∥∥=(1.602×10^-19×0.12)/(1.381×10^-23×ln(1/0.0001))=151 K.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程中涉及多个步骤的数学运算和物理常数的代入，最终得出一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括公式变换、单位转换和数值代入，涉及对溶质偏析临界温度概念的理解和公式应用。虽然计算过程较为直接，但需要综合运用多个知识点，如能量单位转换、对数运算等，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解溶质偏析的概念，掌握指数公式的变形应用，并进行多步单位换算和数值计算。题目涉及能量单位转换(eV→J)、对数运算和临界温度推导，虽然计算过程明确但步骤较多，对学生的公式应用和计算能力要求较高。", "convertible": true, "correct_option": "151 K", "choice_question": "For zinc in copper, c0=wZn=0.0001, E=-0.12 eV, the critical temperature for solute segregation is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "151 K", "B": "298 K", "C": "0.12 eV/kB", "D": "-0.12 eV/kB" }, "correct_answer": "A", "explanation": "正确答案A是通过严格的热力学计算得出，使用公式 Tc = -E/(kB * ln(c0))，其中kB为玻尔兹曼常数。干扰项B利用室温(298K)作为常见参考温度的认知偏差；干扰项C和D故意混淆能量单位(eV)与温度单位(K)的转换关系，特别是D项还保留了负号以强化直觉误导。这些干扰项专门针对AI模型在单位转换和负号处理上的常见弱点设计。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1969, "question": "Please compare the distortion energy of the two dislocations b1= a/2[111] and b2=a[100] in FCC crystals, which one is greater.", "answer": "∣b₁∣=a/2√(1+1+1)=√3/2a ∣b₂∣=a√(1+0+0)=a Therefore, the distortion energy of b1 is smaller.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求计算两个位错的畸变能并进行比较，解答过程中涉及数值计算和公式应用（如计算位错矢量的模），最终通过计算结果得出比较结论。 | 知识层次: 题目涉及基本的矢量长度计算和公式应用，属于简单计算和直接套用类型，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要计算两个位错的畸变能并进行比较，但仅涉及基本的矢量模长公式和简单比较，无需复杂推导或多步骤计算。正确选项直接给出了计算过程和结论，符合等级2的标准。", "convertible": true, "correct_option": "the distortion energy of b1 is smaller", "choice_question": "Please compare the distortion energy of the two dislocations b1= a/2[111] and b2=a[100] in FCC crystals, which one is greater.", "conversion_reason": "The original question is a calculation question with a definitive answer that can be presented as a choice in a multiple-choice format. The answer is clear and can be directly used as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The distortion energy of b1 is smaller due to lower Burgers vector magnitude", "B": "The distortion energy of b2 is smaller because [100] is a perfect slip direction in FCC", "C": "Both have equal distortion energy since they are both perfect dislocations in FCC", "D": "The distortion energy of b1 is greater because it has mixed edge/screw character" }, "correct_answer": "A", "explanation": "Correct answer is A because distortion energy scales with b², and b1 has smaller magnitude (a√3/2 vs a). B is wrong but tempting because [100] is not a slip direction in FCC. C is wrong but uses perfect dislocation confusion. D is wrong but exploits character misconception - energy depends on b² not character.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3423, "question": "Which commonly used alloying elements belong to the γ-phase expanding elements?", "answer": "Nickel, manganese, cobalt, carbon, nitrogen, and copper expand the γ-phase region.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举γ相扩展元素，答案以文字形式给出具体元素名称，属于需要文字解释和论述的简答题类型 | 知识层次: 题目考查对γ-phase expanding elements的基本记忆和分类，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 该题目属于基础概念记忆类型，仅需识别γ相扩展元素的基本分类。选择题型中只需从给定选项中识别正确元素组合，不涉及概念解释或复杂分析，属于最基础的定义识别难度等级。", "convertible": true, "correct_option": "Nickel, manganese, cobalt, carbon, nitrogen, and copper expand the γ-phase region.", "choice_question": "Which of the following groups of elements are commonly known as γ-phase expanding elements?", "conversion_reason": "The answer is a standard list of elements, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Nickel, manganese, cobalt, carbon, nitrogen, and copper", "B": "Chromium, molybdenum, silicon, tungsten, and vanadium", "C": "Aluminum, titanium, niobium, and zirconium", "D": "Phosphorus, sulfur, lead, and bismuth" }, "correct_answer": "A", "explanation": "The correct answer is A because these elements are well-documented γ-phase (austenite) stabilizers that expand the austenitic phase field in iron-based alloys. Option B contains γ-phase contracting elements that stabilize ferrite, creating a strong contrast effect. Option C mixes some correct elements (Ni, Mn) with ferrite stabilizers (Al, Ti) to exploit pattern recognition errors. Option D uses entirely incorrect elements that are not even typical alloying additions, targeting overgeneralization tendencies.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2355, "question": "Calculate the packing density of the CsCl crystal structure (assuming ions are in contact along the body diagonal).", "answer": "The CsCl crystal has a simple cubic structure. The radii of the Cs⁺ and Cl⁻ ions are r_Cs⁺ = 0.165 nm and r_Cl⁻ = 0.181 nm, respectively. Assuming the ions are in contact along the body diagonal, the diagonal length d = 2(r_Cs⁺ + r_Cl⁻) = 2(0.165 + 0.181) nm = 0.692 nm. The lattice constant a = d/√3 = 0.692 nm/√3 = 0.3995 nm. A unit cell contains one Cs⁺ ion and one Cl⁻ ion, so the packing density η_CsCl of the CsCl crystal structure is η_CsCl = [4π(r_Cs⁺³ + r_Cl⁻³)/3] / a³ = [4π(0.165³ + 0.181³)] / (3 × 0.3995³) = 0.685.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，包括计算离子半径、晶格常数和堆积密度等步骤，最终得出一个具体的数值结果。 | 知识层次: 题目涉及多步计算（离子半径求和、体对角线计算、晶格常数推导、堆积密度公式应用），需要理解CsCl晶体结构特征并正确关联各参数，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构的基本概念（如简单立方结构、离子半径、体对角线接触条件），并能够正确应用几何关系（体对角线与晶格常数的关系）进行多步计算。题目还要求综合运用体积公式和密度公式，涉及多个变量的代入和计算步骤，但整体思路清晰，属于典型的综合性计算问题。", "convertible": true, "correct_option": "0.685", "choice_question": "What is the packing density of the CsCl crystal structure (assuming ions are in contact along the body diagonal)?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.685", "B": "0.740", "C": "0.524", "D": "0.680" }, "correct_answer": "A", "explanation": "The correct packing density for CsCl structure is 0.685 when ions are in contact along the body diagonal. Option B (0.740) is the packing density for FCC structure, exploiting common confusion between different crystal structures. Option C (0.524) is the packing density for simple cubic, another common misapplication. Option D (0.680) is numerically close but incorrect, designed to catch rounding errors or calculation mistakes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4838, "question": "At room temperature the electrical conductivity and the electron mobility for aluminum are 3.8 x 10^7 (Ω·m)^-1 and 0.0012 m^2/V·s, respectively. Compute the number of free electrons per cubic meter for aluminum at room temperature.", "answer": "the number of free electrons per cubic meter for aluminum at room temperature is 1.98 x 10^29 m^-3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的电导率和电子迁移率数据，应用相关公式计算铝在室温下的自由电子密度。解答过程涉及数值计算和公式应用，答案是一个具体的数值结果。 | 知识层次: 题目要求应用基本的电导率和电子迁移率公式进行简单计算，属于直接套用公式的范畴，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算铝在室温下的自由电子数密度，只需直接套用电导率与电子迁移率的关系公式（σ = n e μ），并进行简单的代数运算即可得到答案。无需复杂的推导或多步骤计算，属于最基础的应用题。", "convertible": true, "correct_option": "1.98 x 10^29 m^-3", "choice_question": "At room temperature the electrical conductivity and the electron mobility for aluminum are 3.8 x 10^7 (Ω·m)^-1 and 0.0012 m^2/V·s, respectively. The number of free electrons per cubic meter for aluminum at room temperature is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.98 x 10^29 m^-3", "B": "3.16 x 10^28 m^-3", "C": "4.75 x 10^27 m^-3", "D": "6.33 x 10^26 m^-3" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula n = σ/(eμ), where σ is conductivity (3.8x10^7 Ω^-1·m^-1), e is electron charge (1.6x10^-19 C), and μ is mobility (0.0012 m^2/V·s). Option B is derived by incorrectly using the hole mobility value for aluminum. Option C results from mistakenly using the conductivity unit as Ω·m instead of (Ω·m)^-1. Option D comes from an incorrect assumption that aluminum has the same electron density as copper at room temperature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2168, "question": "Calculate the shear strength τ of 40 steel, given the shear modulus of iron GFe=7.9×1010Pa, Burgers vector b=0.25nm, and particle spacing λ=2.4μm", "answer": "τ=Gb/λ=7.9×1010×2.5×10-10/2.4×10-5=8.23×105Pa", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的参数和公式进行数值计算，最终得出具体的数值结果。答案的形式是一个具体的计算结果，解答过程涉及公式应用和数值运算。 | 知识层次: 题目主要考查基本公式的直接应用和简单计算，涉及到的知识点较为基础，思维过程较为直接，无需多步计算或综合分析。 | 难度: 在选择题型内，该题目属于单一公式直接计算的难度等级。题目明确给出了所有必要的参数（G, b, λ），并直接要求套用公式τ=Gb/λ进行计算。解题步骤简单直接，无需额外的概念理解或公式组合，仅需进行基本的单位换算和数值代入。在选择题的背景下，这种类型的题目属于最基础的难度级别。", "convertible": true, "correct_option": "8.23×10^5Pa", "choice_question": "Calculate the shear strength τ of 40 steel, given the shear modulus of iron GFe=7.9×10^10Pa, Burgers vector b=0.25nm, and particle spacing λ=2.4μm. The shear strength τ is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.23×10^5Pa", "B": "3.29×10^6Pa", "C": "1.65×10^7Pa", "D": "4.12×10^4Pa" }, "correct_answer": "A", "explanation": "正确答案A是通过τ=G*b/λ计算得出。干扰项B通过错误地使用2π因子（τ=G*b/(2πλ)）产生，这是常见公式混淆。干扰项C错误地将纳米和微米单位混淆（τ=G*b/λ，但错误地将λ视为2.4nm）。干扰项D通过错误地平方λ（τ=G*b/λ^2）产生，利用了材料科学中常见的指数错误直觉。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3313, "question": "What is temper brittleness?", "answer": "When some steels are tempered within a certain temperature range, their impact toughness significantly decreases compared to being tempered at lower temperatures. This embrittlement phenomenon is called temper brittleness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"temper brittleness\"进行文字解释和论述，答案提供了详细的定义和现象描述，符合简答题的特征。 | 知识层次: 题目考查对\"temper brittleness\"这一基本概念的定义和现象描述，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆（temper brittleness的定义），但正确选项需要理解并描述一个特定的材料现象（特定温度区间回火导致的韧性下降），而不仅仅是简单的名词定义。这比单纯记忆术语（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "When some steels are tempered within a certain temperature range, their impact toughness significantly decreases compared to being tempered at lower temperatures. This embrittlement phenomenon is called temper brittleness.", "choice_question": "Which of the following best describes temper brittleness?", "conversion_reason": "The answer is a standard definition or concept, which can be adapted into a multiple-choice format by presenting it as the correct option among plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When some steels are tempered within a certain temperature range, their impact toughness significantly decreases compared to being tempered at lower temperatures. This embrittlement phenomenon is called temper brittleness.", "B": "A phenomenon where rapid cooling of steel causes excessive hardness and brittleness due to martensite formation, which can be mitigated by tempering.", "C": "The loss of ductility in alloys when exposed to high temperatures for prolonged periods, caused by grain boundary segregation of impurities.", "D": "An irreversible embrittlement occurring in low-alloy steels when tempered below 300°C, resulting from carbide precipitation at dislocations." }, "correct_answer": "A", "explanation": "Option A correctly defines temper brittleness as the reduction in impact toughness when steels are tempered in a specific temperature range. Option B describes quench brittleness, not temper brittleness. Option C describes temper embrittlement, a different phenomenon related to long-term high-temperature exposure. Option D incorrectly limits the temperature range and describes a different mechanism involving carbide precipitation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2845, "question": "For FCC and BCC metals during plastic deformation, the relationship between flow stress and dislocation density ρ is given by τ=τ0+αGb√ρ, where τ0 is the stress required for dislocation motion without interference from other dislocations, i.e., the shear stress without work hardening, G is the shear modulus, b is the Burgers vector of the dislocation, and α is a material-dependent constant, α=0.3∼0.5. If a Cu single crystal has τ0=700 kPa, initial dislocation density ρ0=10^5 cm−2, G=42×10^3 MPa, b=0.256 nm, α=0.4, what is the critical resolved shear stress?", "answer": "τ=τ0+αGb√ρ0=700+0.4×42×10^6×0.256×10^−9×√10^9=836 kPa", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出一个具体的数值结果（临界分解剪切应力）。解答过程涉及公式应用和单位换算，属于典型的计算题类型。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，即通过给定的公式和参数计算临界分切应力。虽然需要理解公式中各参数的含义，但整体上属于直接套用公式进行计算，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然题目提供了多个参数和公式，但解题过程仅需直接套用给定的公式τ=τ0+αGb√ρ0，并进行简单的数值计算。不需要多个公式的组合或复杂的推导步骤，因此属于等级2难度。", "convertible": true, "correct_option": "836 kPa", "choice_question": "For FCC and BCC metals during plastic deformation, the relationship between flow stress and dislocation density ρ is given by τ=τ0+αGb√ρ, where τ0 is the stress required for dislocation motion without interference from other dislocations, i.e., the shear stress without work hardening, G is the shear modulus, b is the Burgers vector of the dislocation, and α is a material-dependent constant, α=0.3∼0.5. If a Cu single crystal has τ0=700 kPa, initial dislocation density ρ0=10^5 cm−2, G=42×10^3 MPa, b=0.256 nm, α=0.4, what is the critical resolved shear stress?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "836 kPa", "B": "700 kPa", "C": "1.12 MPa", "D": "954 kPa" }, "correct_answer": "A", "explanation": "正确答案A是通过公式τ=τ0+αGb√ρ计算得出，其中需要将单位统一转换为MPa和m，并正确计算平方根。干扰项B仅给出τ0值，忽略了位错密度的影响；干扰项C错误地将G值直接相加而未考虑平方根计算；干扰项D则错误地使用了α=0.5而非题目给定的0.4。这些干扰项利用了单位转换错误、公式理解偏差和参数误用等常见认知陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4919, "question": "For cooling, what is the nature of the surface stresses?", "answer": "For cooling, the surface stresses will be tensile in nature since the interior contracts to a lesser degree than the cooler surface.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对冷却过程中表面应力的性质进行解释，答案提供了详细的文字论述，符合简答题的特征。 | 知识层次: 题目考查冷却过程中表面应力的基本性质和原因，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（冷却时表面应力的性质），但需要考生理解并描述应力产生的机制（内部和表面收缩差异导致拉伸应力）。这比单纯记忆定义（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "For cooling, the surface stresses will be tensile in nature since the interior contracts to a lesser degree than the cooler surface.", "choice_question": "What is the nature of the surface stresses for cooling?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Tensile, due to greater contraction of the cooler surface layer", "B": "Compressive, as the interior resists thermal contraction", "C": "Shear-dominant, caused by differential contraction rates", "D": "Neutral, balanced by stress relaxation mechanisms" }, "correct_answer": "A", "explanation": "The correct answer is A because during cooling, the surface contracts more than the interior, creating tensile stresses. Option B is a common misconception where students confuse heating/cooling stress directions. Option C exploits confusion between normal and shear stresses. Option D appeals to intuitive but incorrect assumptions about stress relaxation at lower temperatures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 940, "question": "Analyze the causes of secondary banded structure formation.", "answer": "The formation of secondary banded structure is the result of solid-state transformation. The white bands are proeutectoid ferrite, and the black bands are pearlite, which must form on the basis of primary bands. These bands are all related to element segregation and the special distribution of inclusions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析二次带状结构形成的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析二次带状结构的形成原因，涉及固态相变、先共析铁素体和珠光体的形成机制，以及元素偏析和夹杂物分布的影响。这需要综合运用材料科学中的相变理论、显微组织分析等知识，进行机理的解释和推理分析，属于较高层次的认知能力要求。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求深入理解二次带状结构的形成机理，包括固态相变、先共析铁素体和珠光体的形成过程，以及元素偏析和夹杂物特殊分布的综合影响。正确选项不仅需要识别现象，还需要解释多层次的复杂因果关系，涉及材料科学中较深层次的理论知识。这种题目在选择题中属于需要全面分析复杂现象的典型代表，远超出基础概念识别的难度水平。", "convertible": true, "correct_option": "The formation of secondary banded structure is the result of solid-state transformation. The white bands are proeutectoid ferrite, and the black bands are pearlite, which must form on the basis of primary bands. These bands are all related to element segregation and the special distribution of inclusions.", "choice_question": "Which of the following best describes the causes of secondary banded structure formation?", "conversion_reason": "The answer is a standard explanation that can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best description of the causes.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The formation of secondary banded structure is the result of solid-state transformation. The white bands are proeutectoid ferrite, and the black bands are pearlite, which must form on the basis of primary bands. These bands are all related to element segregation and the special distribution of inclusions.", "B": "Secondary banded structures form due to rapid quenching from the austenitic phase, creating alternating layers of martensite and retained austenite with distinct hardness differences.", "C": "The banding results from periodic fluctuations in cooling rate during solidification, causing alternating zones of dendritic and eutectic microstructures.", "D": "It is caused by mechanical working processes where deformation bands align with crystallographic planes, creating alternating regions of recrystallized and work-hardened material." }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the solid-state transformation mechanism involving proeutectoid ferrite and pearlite formation based on primary bands. Option B incorrectly associates it with quenching effects, exploiting the common confusion between transformation products. Option C creates a plausible but incorrect solidification-based explanation, targeting those who overlook the solid-state nature. Option D appeals to mechanical processing intuition, a classic red herring for those not considering the metallurgical origins.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2711, "question": "The activation energy required to form a vacancy in a certain crystal is 0.32×10^-18 J. At 800°C, there is one vacancy per 1×10^4 atoms. At what temperature will there be one vacancy per 10^3 atoms?", "answer": "According to the Arrhenius equation: $$ \\\\ln{\\\\frac{n}{N}}=\\\\ln A-{\\\\frac{E}{{k}\\\\ T}}$$ Substituting the known conditions into the equation: $$ \\\\ln10^{-4}=\\\\ln A-\\\\frac{0.32\\\\times10^{-18}}{1.38\\\\times10^{-23}\\\\times1073}$$ We obtain: $$ \\\\ln A=12.4$$ And: $$ {\\\\bf{In}}10^{-3}=12.4-\\\\frac{0.32\\\\times10^{-18}}{1.38\\\\times10^{-23}\\\\times\\\\mathit{T}}.$$ Therefore: $$ \\\\operatorname{T}=1201\\\\operatorname{K}=928^{\\\\circ}{\\\\mathbb{C}}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（Arrhenius方程）来求解温度，答案给出了具体的计算过程和结果。 | 知识层次: 题目涉及多步计算和公式应用，需要理解并运用阿伦尼乌斯方程进行温度与空位浓度的关系计算，同时需要将不同条件下的数据进行关联和综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解并应用阿伦尼乌斯方程进行多步计算，涉及对数运算和温度转换，同时需要综合分析不同条件下的变量关系。虽然题目提供了正确选项，但解题过程需要较强的概念关联和计算能力。", "convertible": true, "correct_option": "928°C", "choice_question": "The activation energy required to form a vacancy in a certain crystal is 0.32×10^-18 J. At 800°C, there is one vacancy per 1×10^4 atoms. At what temperature will there be one vacancy per 10^3 atoms?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "928°C", "B": "1024°C", "C": "756°C", "D": "872°C" }, "correct_answer": "A", "explanation": "正确答案A(928°C)通过Arrhenius方程计算得出，考虑温度与空位浓度的对数关系。干扰项B(1024°C)利用直觉上认为需要更高温度形成更多空位的认知偏差，但实际过高估计了指数关系。干扰项C(756°C)通过错误使用线性近似产生，忽略了激活能量的指数影响。干扰项D(872°C)是常见单位换算错误的结果，混淆了摄氏与开尔文温标。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4442, "question": "Why does fracture strength increase with decreasing specimen size?", "answer": "The fracture strength increases with decreasing specimen size because as specimen size decreases, the probability of the existence of a flaw that is capable of initiating a crack diminishes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对现象进行解释和论述，答案是一段文字解释，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求解释断裂强度随试样尺寸减小而增加的机理，涉及缺陷概率与裂纹萌生的关联分析，需要综合运用材料科学中的断裂力学原理进行推理和解释，思维过程具有较高的深度要求。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解断裂强度的基本概念，还需要掌握材料缺陷与尺寸效应的复杂关系。正确选项涉及概率性缺陷分布、裂纹萌生机理等深层次知识，需要综合运用材料科学原理进行推理分析。这种在选择题中要求解释复杂现象背后机理的题目，对考生的知识深度和逻辑思维能力都有很高要求，远超单纯记忆或简单应用类选择题的难度水平。", "convertible": true, "correct_option": "The fracture strength increases with decreasing specimen size because as specimen size decreases, the probability of the existence of a flaw that is capable of initiating a crack diminishes.", "choice_question": "Why does fracture strength increase with decreasing specimen size?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The surface-to-volume ratio increases, reducing stress concentration effects", "B": "Dislocation motion becomes more restricted in smaller volumes", "C": "Smaller specimens have higher crystallinity due to faster cooling rates", "D": "Grain boundary strengthening dominates at nanoscale dimensions" }, "correct_answer": "B", "explanation": "The correct answer is B because in smaller specimens, dislocations have less space to move and multiply, leading to higher strength. Option A is a cognitive bias trap - while surface effects are important, they don't directly explain fracture strength increase. Option C exploits confusion between specimen size and processing conditions. Option D is a professional intuition trap - while grain boundaries are important, this mechanism isn't the primary reason for size-dependent fracture strength.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 316, "question": "The melting point of copper T_m=1385K, at an undercooling of △T=0.2T_m, crystalline copper is obtained through homogeneous nucleation. Calculate the critical nucleus radius at this temperature. (ΔH=1628J/cm³, γ=1.77×10⁻⁵J/cm²)", "answer": "From ΔG_v = - (ΔH × ΔT) / T_m = - (1628 × 0.2 × 1385) / 1385 = -325.6 J/cm³. The critical nucleus radius γ* = - (2 × γ) / ΔG_v = - (2 × 1.77 × 10⁻⁵) / (-325.6) = 1.087 × 10⁻⁷ cm ≈ 1.087 nm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和数据进行数值计算，最终得出临界核半径的具体数值。答案展示了详细的推导和计算过程，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括理解过冷度的概念、应用临界核半径公式，并进行数值计算。虽然不涉及复杂的综合分析或创新应用，但需要将多个概念和公式关联起来进行计算。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如临界核半径、过冷度、自由能变化等）并进行多步骤计算。虽然题目提供了公式和数值，但需要正确应用公式并完成综合计算才能得出答案。", "convertible": true, "correct_option": "1.087 nm", "choice_question": "The melting point of copper T_m=1385K, at an undercooling of △T=0.2T_m, crystalline copper is obtained through homogeneous nucleation. What is the critical nucleus radius at this temperature? (ΔH=1628J/cm³, γ=1.77×10⁻⁵J/cm²)", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.087 nm", "B": "2.174 nm (using ΔT=0.1T_m instead of 0.2T_m)", "C": "0.543 nm (incorrectly using surface energy γ=3.54×10⁻⁵J/cm²)", "D": "1.632 nm (miscalculating ΔH as 2442J/cm³)" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the formula r*=2γTm/ΔHΔT with proper parameters. Option B exploits cognitive bias by using half the required undercooling, a common oversight. Option C traps those who confuse surface energy values. Option D targets those who incorrectly scale the enthalpy change. Advanced AI might fail by fixating on plausible-looking but contextually wrong parameters.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2505, "question": "What are the performance characteristics of graphite?", "answer": "Graphite has a loose structure and certain electrical conductivity, and is commonly used as a lubricant.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释石墨的性能特点，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查石墨的基本性能特征，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对石墨基本性能特征的记忆，属于基础概念的直接回忆。正确选项明确描述了石墨的结构特点和常见用途，无需复杂推理或概念间的关联分析，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Graphite has a loose structure and certain electrical conductivity, and is commonly used as a lubricant.", "choice_question": "Which of the following describes the performance characteristics of graphite?", "conversion_reason": "The answer is a standard description of graphite's characteristics, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Graphite exhibits anisotropic thermal conductivity with high in-plane conductivity but low through-plane conductivity", "B": "Graphite demonstrates isotropic mechanical properties due to its uniform layered structure", "C": "Graphite shows metallic bonding characteristics leading to high electrical resistivity", "D": "Graphite possesses high surface energy resulting in poor lubricating properties" }, "correct_answer": "A", "explanation": "The correct answer is A because graphite's layered structure creates strong in-plane covalent bonds (high conductivity) but weak van der Waals forces between layers (low through-plane conductivity). Option B is incorrect because graphite's mechanical properties are highly anisotropic despite appearing uniform - this exploits the 'uniform appearance' cognitive bias. Option C is wrong by reversing the actual low resistivity of graphite - this uses the 'metallic bonding' intuition trap. Option D falsely associates surface energy with lubricity - this employs the multi-level verification trap by mixing valid concepts (surface energy) with incorrect conclusions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3046, "question": "What type of chemical bond is primarily found in nitrides? A. Metallic bond B. Covalent bond C. Molecular bond D. Ionic bond", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对化学键类型的基本概念记忆和理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要记忆氮化物中主要的化学键类型（共价键），但选项中的其他键类型（金属键、分子键、离子键）与共价键有较明显的区别，只需基础的概念理解和简单辨析即可选出正确答案。不需要复杂的分析或深度理解多个概念之间的关系。", "convertible": true, "correct_option": "B. Covalent bond", "choice_question": "What type of chemical bond is primarily found in nitrides?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ionic bond with partial covalent character", "B": "Pure covalent bond", "C": "Metallic bond with electron delocalization", "D": "Van der Waals-bonded molecular solid" }, "correct_answer": "B", "explanation": "Nitrides primarily form covalent bonds due to the small size and high electronegativity of nitrogen, which favors orbital overlap. Option A exploits the common misconception that metal nitrides must be ionic. Option C targets the tendency to overgeneralize metallic bonding to all inorganic compounds. Option D capitalizes on the superficial similarity to molecular nitrogen's bonding.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1545, "question": "5．Extended dislocation", "answer": "A complete dislocation dissociates into two partial dislocations and the stacking fault between them, and this dislocation configuration is called an extended dislocation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Extended dislocation\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对扩展位错（extended dislocation）这一基本概念的定义和构成的理解，属于材料科学中位错理论的基础知识记忆范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆（定义、分类、基本原理等），但需要考生准确理解并区分\"complete dislocation\"、\"partial dislocations\"和\"stacking fault\"这几个专业术语及其相互关系。这比单纯记忆一个简单定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "A complete dislocation dissociates into two partial dislocations and the stacking fault between them, and this dislocation configuration is called an extended dislocation.", "choice_question": "下列关于Extended dislocation的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A complete dislocation dissociates into two partial dislocations and the stacking fault between them, and this dislocation configuration is called an extended dislocation", "B": "Extended dislocations occur when two perfect dislocations combine to form a single dislocation with double Burgers vector", "C": "Extended dislocations are formed by the interaction of edge and screw dislocations in FCC metals under high stress", "D": "The width of an extended dislocation is determined solely by the elastic modulus of the material" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines extended dislocation as the dissociation of a complete dislocation into partials with stacking fault. Option B incorrectly describes perfect dislocations combining, which actually forms superdislocations. Option C mixes edge/screw dislocation concepts with extended dislocation formation, creating a plausible but incorrect scenario. Option D uses a cognitive bias by oversimplifying the width determination (which depends on stacking fault energy, not just elastic modulus) while sounding technically plausible.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1869, "question": "Among the seven crystal systems, the number of crystal systems belonging to the highest crystal category is A.1 B.2 C.3 D.4", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项A、B、C、D中选择正确答案 | 知识层次: 题目考查对晶体系统分类的基础概念记忆，属于对晶体学基本分类体系的直接考察，不需要复杂的应用或分析过程。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需识别和回忆七种晶系中最高晶系的分类数量，无需复杂辨析或深度理解。题目直接给出明确选项，解题步骤简单，属于最基础的难度等级。", "convertible": true, "correct_option": "A", "choice_question": "Among the seven crystal systems, the number of crystal systems belonging to the highest crystal category is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The activation energy for vacancy diffusion in BCC iron is lower than in FCC iron at 900°C", "B": "The activation energy for vacancy diffusion in FCC iron is lower than in BCC iron at 900°C", "C": "Both crystal structures show identical vacancy diffusion activation energies at 900°C", "D": "The comparison cannot be made without knowing the exact impurity content" }, "correct_answer": "A", "explanation": "The correct answer is A because BCC structures generally have lower activation energies for vacancy diffusion due to their more open structure, despite FCC's higher equilibrium vacancy concentration. Option B is a cognitive bias trap, exploiting the common misconception that FCC's higher vacancy concentration implies easier diffusion. Option C is a symmetry fallacy, suggesting identical behavior where crystal structure differences are crucial. Option D is a red herring, introducing an unnecessary impurity consideration that doesn't fundamentally affect the intrinsic diffusion comparison.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 1, "correct_answers": 1, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 727, "question": "At low temperatures, the diffusion that generally occurs in crystals is extrinsic diffusion", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对晶体扩散类型的基础概念记忆，特别是低温下扩散类型的判断，属于定义和分类的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念正误判断，仅需记忆低温下晶体扩散类型的基本定义即可作答，无需复杂理解或分析步骤。", "convertible": true, "correct_option": "√", "choice_question": "At low temperatures, the diffusion that generally occurs in crystals is extrinsic diffusion", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain advanced ceramics like transformation-toughened zirconia can exhibit significant plasticity. The use of 'all' makes this statement incorrect. This tests understanding of exceptions in material behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3584, "question": "Would you expect MgO or magnesium to have the higher modulus of elasticity? Explain.", "answer": "( MgO has ionic bonds, which are strong compared to the metallic bonds in Mg. A higher force will be required to cause the same separation between the ions in MgO compared to the atoms in Mg. Therefore, MgO should have the higher modulus of elasticity. In Mg, E=6 × 10^{6} psi; in MgO, E=30 × 10^{6} psi.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么MgO的弹性模量比镁高，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求学生理解并比较MgO和Mg的键合类型（离子键与金属键），并解释其对弹性模量的影响。这需要学生将键合类型与材料性能关联起来，进行综合分析，而不仅仅是记忆基本概念或进行简单应用。虽然不涉及多步计算，但需要对概念进行关联和解释，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生比较MgO和Mg的弹性模量，并解释原因。这涉及到对离子键和金属键强度的理解，以及对弹性模量概念的掌握。虽然题目提供了具体数值，但考生仍需进行概念关联和综合分析才能得出正确结论。", "convertible": true, "correct_option": "MgO has the higher modulus of elasticity.", "choice_question": "Which has the higher modulus of elasticity, MgO or magnesium?", "conversion_reason": "The original question asks for a comparison between MgO and magnesium regarding modulus of elasticity, which can be rephrased as a multiple-choice question with a clear correct option derived from the explanation provided in the answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "MgO due to its strong ionic bonding and high melting point", "B": "Magnesium due to its metallic bonding and higher ductility", "C": "Both have similar moduli because they share the same base element", "D": "Magnesium when measured at cryogenic temperatures" }, "correct_answer": "A", "explanation": "The correct answer is A because MgO's strong ionic bonds give it a higher modulus of elasticity than metallic magnesium. B is designed to exploit the common misconception that metallic bonding implies higher stiffness, while C creates confusion by suggesting elemental similarity overrides bonding type. D introduces a specific condition trap where temperature effects might mislead the model.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1593, "question": "Small-angle grain boundaries are composed of dislocations, among which twist boundaries are composed of what type of dislocations?", "answer": "Screw", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求回答特定类型的位错名称，需要简洁的文字回答，而不是从多个选项中选择或判断对错，也不需要复杂的计算。 | 知识层次: 题目考查对晶界和位错类型的基本概念记忆，特别是扭转晶界的组成位错类型，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确理解并区分不同类型位错（如刃位错和螺位错）在晶界中的具体应用。题目要求考生不仅记住小角度晶界的组成，还要明确扭转晶界由螺位错构成这一特定知识点。这比单纯记忆定义（等级1）要求更高，但尚未达到需要复杂概念体系阐述（等级3）的程度。", "convertible": true, "correct_option": "Screw", "choice_question": "Small-angle grain boundaries are composed of dislocations, among which twist boundaries are composed of what type of dislocations?", "conversion_reason": "The answer is a standard term (Screw), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Edge dislocations", "B": "Screw dislocations", "C": "Mixed dislocations with 60° character", "D": "Partial dislocations with Shockley partials" }, "correct_answer": "B", "explanation": "Twist boundaries are composed of screw dislocations because they involve a rotation of the crystal lattice around an axis perpendicular to the boundary plane. Option A exploits the common association of grain boundaries with edge dislocations in tilt boundaries. Option C creates confusion by introducing a specific mixed dislocation angle that appears in some real materials but is irrelevant here. Option D uses advanced dislocation terminology (Shockley partials) that sounds plausible but is unrelated to twist boundaries.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2660, "question": "Using Cu's ka (λ=0.1542 nm), the first line of Cr's X-ray diffraction spectrum was measured at 2θ=64.6°. If the lattice constant a of (bcc) Cr is 0.2885 nm, find the Miller indices corresponding to these spectral lines.", "answer": "According to the formula d_hkl=a/sqrt(h^2+k^2+l^2)=λ/(2sinθ), if 2θ=64.6°, then h^2+k^2+l^2={(2sin(64.6°/2)×0.2885)/0.1542}^2=3.9976≈4. Therefore, this plane is (200), or (020) or (002).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，通过给定的波长、角度和晶格常数，利用布拉格方程计算晶面指数。答案展示了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算（包括布拉格定律的应用和晶面间距公式的计算），并需要将计算结果与晶面指数关联起来。虽然计算过程相对直接，但需要理解X射线衍射的基本原理和立方晶系的晶面间距公式，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解X射线衍射的基本原理，掌握晶面间距的计算公式，并能正确应用布拉格方程。题目涉及多步计算和概念关联，包括角度转换、晶面间距计算和米勒指数的确定。虽然题目提供了必要的公式和数据，但解题过程需要一定的综合分析能力。", "convertible": true, "correct_option": "(200), or (020) or (002)", "choice_question": "Using Cu's ka (λ=0.1542 nm), the first line of Cr's X-ray diffraction spectrum was measured at 2θ=64.6°. If the lattice constant a of (bcc) Cr is 0.2885 nm, what are the Miller indices corresponding to these spectral lines?", "conversion_reason": "The answer is a specific set of Miller indices, which can be presented as distinct options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(200), (020), or (002)", "B": "(110)", "C": "(211)", "D": "(111)" }, "correct_answer": "A", "explanation": "The correct answer is A because for bcc crystals, the first diffraction peak corresponds to the (200) family of planes. Option B is a common mistake as (110) is the first peak for simple cubic structures. Option C exploits the tendency to consider higher-order reflections, while D targets confusion with fcc structures where (111) is the first peak. The calculation requires using Bragg's law with n=1 and correctly identifying the bcc structure factor rules.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 225, "question": "What is Gibbs phase rule?", "answer": "The phase rule is a fundamental law of phase equilibrium derived by Gibbs based on thermodynamic principles, also known as Gibbs phase rule, used to describe the relationship between the number of degrees of freedom, the number of components, and the number of phases in a system at phase equilibrium. The general mathematical expression is F=C-P+2, where F is the number of degrees of freedom, C is the number of components, P is the number of phases, and 2 represents the two variables of temperature and pressure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释Gibbs phase rule的定义和数学表达式，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查Gibbs相律的基本定义和数学表达式，属于基础概念的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆（Gibbs相律的定义和数学表达式），但需要考生理解并描述相律中各变量的含义及其相互关系。相比单纯记忆定义（等级1），该题目要求对概念进行解释和描述（等级2），但不需要进行复杂的概念体系阐述或应用（等级3）。", "convertible": true, "correct_option": "The phase rule is a fundamental law of phase equilibrium derived by Gibbs based on thermodynamic principles, also known as Gibbs phase rule, used to describe the relationship between the number of degrees of freedom, the number of components, and the number of phases in a system at phase equilibrium. The general mathematical expression is F=C-P+2, where F is the number of degrees of freedom, C is the number of components, P is the number of phases, and 2 represents the two variables of temperature and pressure.", "choice_question": "Which of the following best describes Gibbs phase rule?", "conversion_reason": "The answer is a standard definition and description of Gibbs phase rule, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "F = C - P + 2, where F is degrees of freedom, C is components, P is phases, and 2 accounts for temperature and pressure", "B": "F = P - C + 2, where F is phases, C is components, P is degrees of freedom, and 2 represents enthalpy and entropy", "C": "F = C + P - 1, where F is free energy, C is components, P is phases, and 1 accounts for constant volume", "D": "F = (C × P) / 2, where F is phase fraction, C is components, P is phases, and 2 balances the system" }, "correct_answer": "A", "explanation": "The correct answer A presents the exact Gibbs phase rule formulation. Option B reverses the P and C terms and incorrectly associates '2' with enthalpy/entropy. Option C introduces free energy and constant volume, which are irrelevant to phase rule. Option D creates a mathematically plausible but conceptually wrong relationship using phase fraction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3605, "question": "Determine the packing fraction for BCC lithium in the (100) plane.", "answer": "packing fraction = 0.589", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求计算BCC锂在(100)面的堆积分数，需要应用晶体结构相关的公式进行数值计算，最终给出一个具体的数值结果（0.589）。 | 知识层次: 题目要求计算BCC锂在(100)面的堆积分数，这需要应用基本的晶体学公式和几何关系，属于直接套用公式和简单计算的范畴。虽然需要理解BCC结构和堆积分数的概念，但计算过程相对直接，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要理解BCC结构在(100)平面的原子排列方式，但主要涉及基本公式的直接套用（计算平面原子密度与晶格参数的关系），解题步骤相对简单，属于选择题型中中等偏下的难度水平。", "convertible": true, "correct_option": "0.589", "choice_question": "What is the packing fraction for BCC lithium in the (100) plane?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.589", "B": "0.680", "C": "0.740", "D": "0.524" }, "correct_answer": "A", "explanation": "The correct answer is A (0.589) because the packing fraction for BCC in the (100) plane is calculated as the area occupied by atoms divided by the total area of the plane. For BCC, this gives π√3/16 ≈ 0.589. Option B (0.680) mimics the FCC (111) plane packing fraction to exploit crystal system confusion. Option C (0.740) uses the 3D FCC packing fraction to trigger dimensional misunderstanding. Option D (0.524) presents the BCC (110) plane value to test plane-specific knowledge.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2365, "question": "A lightly cross-linked rubber band is stretched several times its original length and returns to its original length after the force is removed. If the stretched rubber band is placed below its glass transition temperature, what will happen to its length after the force is removed? Why?", "answer": "When the stretched rubber band is placed below its glass transition temperature, it transitions into a glassy state. The glass transition causes the atoms to change from delocalized to localized (solidification), so it cannot return to its original length after the external force is removed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释现象并论述原因，答案需要文字解释和论述，没有提供选项或要求计算 | 知识层次: 题目要求分析橡胶带在玻璃化转变温度以下的行为变化，并解释其背后的机理。这需要综合运用材料科学中的高分子物理知识，理解玻璃化转变对材料性能的影响，以及橡胶弹性的基本原理。思维过程涉及多个概念的关联和深层次的理解，属于复杂分析和机理解释的范畴。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "When the stretched rubber band is placed below its glass transition temperature, it transitions into a glassy state. The glass transition causes the atoms to change from delocalized to localized (solidification), so it cannot return to its original length after the external force is removed.", "choice_question": "A lightly cross-linked rubber band is stretched several times its original length and returns to its original length after the force is removed. If the stretched rubber band is placed below its glass transition temperature, what will happen to its length after the force is removed?", "conversion_reason": "The answer is a standard explanation involving the glass transition temperature and its effect on the rubber band's properties, which can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It will maintain its stretched length due to frozen chain mobility below Tg", "B": "It will partially recover due to residual entropy elasticity in the glassy state", "C": "It will return to original length faster due to increased modulus below Tg", "D": "It will exhibit creep deformation until reaching equilibrium length" }, "correct_answer": "A", "explanation": "The correct answer is A because below the glass transition temperature, polymer chains lose mobility and cannot return to their entropically favored coiled state. Option B exploits the misconception that some elasticity persists below Tg. Option C reverses the expected behavior by suggesting faster recovery. Option D introduces creep behavior which is irrelevant to this instantaneous response scenario.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1970, "question": "When CN=6, the ionic radius of Na+ is 0.097nm, what is its radius when CN=4?", "answer": "0.088nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据已知条件(CN=6时的离子半径)通过计算得出CN=4时的离子半径，需要应用离子半径与配位数关系的计算公式，最终给出具体数值答案(0.088nm)。 | 知识层次: 题目涉及离子半径随配位数变化的简单计算，只需要直接应用已知的半径转换关系或经验公式即可得出结果，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需要直接套用已知的离子半径与配位数关系公式，属于单一公式直接计算的简单应用。题目提供了明确的配位数变化和对应的半径值，解题步骤简单直接，无需复杂推理或多步骤计算。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "0.088nm", "choice_question": "When CN=6, the ionic radius of Na+ is 0.097nm, what is its radius when CN=4?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.088nm", "B": "0.097nm", "C": "0.102nm", "D": "0.113nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.088nm) because ionic radii decrease with decreasing coordination number (CN) due to reduced shielding effects. Option B (0.097nm) is a cognitive bias trap - using the same value as CN=6, exploiting the common mistake of assuming radius remains constant. Option C (0.102nm) is a professional intuition trap - suggesting an increase in radius with decreasing CN, which contradicts fundamental principles. Option D (0.113nm) is a multi-level verification trap - using a value from a different ionic radius scale (Shannon-Prewitt vs. Pauling).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 891, "question": "A single crystal test bar of FCC metal with a cross-sectional area of 10cm² is subjected to a compression test along the axial direction. The critical resolved shear stress is known to be 0.1kgf/mm², and the initial orientation of the bar axis is [215]. Please determine the final stable orientation of the crystal (assuming the test bar does not fracture before reaching the stable orientation).", "answer": "The final stable orientation of the crystal: [101].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来确定晶体的最终稳定取向，答案是一个具体的取向[101]，而不是通过计算或选择选项得出的结果。 | 知识层次: 题目需要理解FCC金属的晶体取向、临界分切应力的概念，并进行多步计算和综合分析，以确定晶体的最终稳定取向。这涉及到晶体滑移系统的选择和取向变化的分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合运用晶体学、力学和材料科学的知识。解题过程涉及多个步骤：理解FCC金属的滑移系统、计算施密特因子、确定临界分切应力条件，并推导晶体在压缩过程中的稳定取向。这需要考生不仅掌握基本概念，还要具备将多个知识点关联起来进行综合分析的能力。虽然题目给出了正确选项，但推导过程复杂，涉及矢量计算和晶体取向变化的判断，远超过简单记忆或单一概念应用的难度水平。", "convertible": true, "correct_option": "[101]", "choice_question": "A single crystal test bar of FCC metal with a cross-sectional area of 10cm² is subjected to a compression test along the axial direction. The critical resolved shear stress is known to be 0.1kgf/mm², and the initial orientation of the bar axis is [215]. The final stable orientation of the crystal (assuming the test bar does not fracture before reaching the stable orientation) is:", "conversion_reason": "The answer is a specific orientation [101], which can be presented as a clear option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[101]", "B": "[111]", "C": "[215]", "D": "[110]" }, "correct_answer": "A", "explanation": "The correct answer is [101] because in FCC crystals under compression, the stable end orientation aligns with the slip direction that maximizes the Schmid factor. Option B [111] is a common slip direction but not the stable end orientation. Option C [215] exploits the initial orientation bias. Option D [110] is a plausible but incorrect slip plane normal direction.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3293, "question": "What is a pearlite colony?", "answer": "In lamellar pearlite, the region where ferrite and cementite are alternately arranged in layers with roughly the same orientation is called a pearlite colony or pearlite nodule.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"pearlite colony\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对pearlite colony这一基本概念的定义和描述，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考查的是基础概念记忆，但需要考生准确理解并描述珠光体团（pearlite colony）的定义和结构特征。这比简单的定义记忆（等级1）要求更高，需要考生能够解释和描述概念（等级2），但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "In lamellar pearlite, the region where ferrite and cementite are alternately arranged in layers with roughly the same orientation is called a pearlite colony or pearlite nodule.", "choice_question": "Which of the following best describes a pearlite colony?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting the correct definition among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In lamellar pearlite, the region where ferrite and cementite are alternately arranged in layers with roughly the same orientation", "B": "A single continuous phase of cementite formed during rapid quenching of austenite", "C": "The boundary region between pearlite and proeutectoid ferrite in hypoeutectoid steels", "D": "An aggregation of spheroidized cementite particles in tempered steels" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a pearlite colony as the characteristic lamellar arrangement of ferrite and cementite with shared orientation. Option B describes martensite formation, exploiting rapid cooling confusion. Option C targets boundary region misconceptions in phase diagrams. Option D misleads by describing spheroidized structures from tempering, not pearlite formation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3839, "question": "Observation of a microstructure shows that there is 28% eutectic and 72% primary β in an Al-Li alloy. Determine the composition of the alloy and whether it is hypoeutectic or hypereutectic.", "answer": "17.46% li, hypereutectic", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过观察到的微观结构比例（28%共晶和72%初生β）来计算合金的成分（17.46% Li）并判断其属于亚共晶还是过共晶（hypereutectic）。这需要应用杠杆定律等计算方法和相图知识，属于典型的计算题。 | 知识层次: 题目需要应用杠杆定律进行多步计算，涉及相图分析和成分判断，需要概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解共晶反应、杠杆定律等概念，并进行多步计算和综合分析。题目要求根据显微组织比例反推合金成分并判断亚共晶或过共晶类型，涉及多个知识点的关联应用，但选项已给出正确答案，降低了部分难度。", "convertible": true, "correct_option": "17.46% Li, hypereutectic", "choice_question": "An Al-Li alloy microstructure shows 28% eutectic and 72% primary β. What is the composition of the alloy and is it hypoeutectic or hypereutectic?", "conversion_reason": "The answer is a specific composition and classification, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "17.46% Li, hypereutectic", "B": "8.73% Li, hypoeutectic", "C": "22.1% Li, hypoeutectic", "D": "12.5% Li, hypereutectic" }, "correct_answer": "A", "explanation": "The correct answer is A because the lever rule calculation for the Al-Li phase diagram shows that 72% primary β corresponds to 17.46% Li composition, which is above the eutectic point (9.9% Li) making it hypereutectic. Option B is a common error where the Li percentage is halved due to misapplying the lever rule. Option C reverses the hypoeutectic/hypereutectic classification while using a plausible composition. Option D combines an incorrect composition with the correct classification to create a tempting but wrong choice.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3448, "question": "List several types of ledeburitic steel you are familiar with?", "answer": "High-speed steel, Cr12, Cr12MoV, etc. all belong to ledeburitic steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列出几种熟悉的莱氏体钢类型，答案以文字形式列举具体例子，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对莱氏体钢（ledeburitic steel）分类的基本记忆，只需列举熟悉的类型，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅要求列举几种莱氏体钢的常见类型，属于基础概念记忆的范畴。正确选项直接提供了具体的钢种名称（如高速钢、Cr12、Cr12MoV等），无需复杂的分析或推理过程。题目仅测试学生对莱氏体钢分类的简单记忆能力，因此属于选择题型中最基础的难度等级。", "convertible": true, "correct_option": "High-speed steel, Cr12, Cr12MoV, etc. all belong to ledeburitic steel.", "choice_question": "Which of the following are types of ledeburitic steel?", "conversion_reason": "The answer provided is a standard list of terms related to ledeburitic steel, which can be formatted into a multiple-choice question by presenting these terms as options and asking the student to identify the correct ones.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High-speed steel", "B": "Austenitic stainless steel", "C": "Low-carbon steel", "D": "Dual-phase steel" }, "correct_answer": "A", "explanation": "High-speed steel is a type of ledeburitic steel due to its high carbon and alloy content forming ledeburite microstructure. Austenitic stainless steel (B) is incorrect as it has austenitic structure, not ledeburitic. Low-carbon steel (C) cannot form ledeburite due to insufficient carbon. Dual-phase steel (D) is a modern high-strength steel with ferrite-martensite structure, unrelated to ledeburite formation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2450, "question": "When using X-ray detection, how does the diffraction of polymer texture appear?", "answer": "The diffuse rings of polymer texture consist of diffuse peaks (rather than the discrete reflections observed in crystals).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释聚合物纹理在X射线检测中的衍射表现，答案提供了详细的文字描述和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对聚合物X射线衍射图案的基本特征的理解和记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及X射线衍射和聚合物结构的基础概念，但正确选项要求考生能够区分晶体和非晶体（聚合物）的衍射模式差异。这需要考生不仅记住定义，还要理解衍射图案的特征（如漫射环与离散反射的区别），属于概念解释和描述的层次。不过题目不需要复杂的推导或多概念整合，因此不属于最高难度等级。", "convertible": true, "correct_option": "The diffuse rings of polymer texture consist of diffuse peaks (rather than the discrete reflections observed in crystals).", "choice_question": "When using X-ray detection, how does the diffraction of polymer texture appear?", "conversion_reason": "The answer is a standard description of the diffraction pattern of polymer texture, which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diffuse rings consisting of broad peaks", "B": "Sharp discrete spots forming Laue patterns", "C": "Concentric circles with uniform intensity distribution", "D": "Elliptical patterns showing preferred orientation" }, "correct_answer": "A", "explanation": "The correct answer is A because polymer textures exhibit diffuse rings due to their semi-crystalline nature, where the crystalline regions produce broad diffraction peaks rather than sharp spots. Option B is incorrect as it describes single crystal diffraction. Option C is a trap for those assuming perfect isotropy, ignoring real polymer texture variations. Option D exploits the common misconception that all anisotropic materials show elliptical patterns, while polymers typically maintain ring symmetry.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3381, "question": "Why are medium carbon (alloy) steels mostly used to manufacture gearbox gears for machine tools?", "answer": "Their working conditions are much better than those of automobiles, requiring certain toughness in the core and higher hardness on the surface.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么中碳（合金）钢主要用于制造机床齿轮箱齿轮，答案提供了文字解释和论述，说明其工作条件和性能要求，符合简答题的特征。 | 知识层次: 题目需要结合材料科学中的碳钢性能特点（如韧性、硬度）与具体应用场景（齿轮箱齿轮的工作条件）进行综合分析，涉及多概念关联和中等程度的推理分析。 | 难度: 在选择题中属于较高难度，题目涉及多个概念的综合分析，包括材料性能（韧性、硬度）、工作条件比较（机床齿轮箱与汽车齿轮的差异）以及材料选择依据。解题需要将材料科学知识与工程应用场景进行多角度关联，并理解表面处理与核心性能的不同要求。这种需要跨领域知识整合的题目在选择题型中属于较复杂类型。", "convertible": true, "correct_option": "Their working conditions are much better than those of automobiles, requiring certain toughness in the core and higher hardness on the surface.", "choice_question": "Why are medium carbon (alloy) steels mostly used to manufacture gearbox gears for machine tools?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Their working conditions are much better than those of automobiles, requiring certain toughness in the core and higher hardness on the surface.", "B": "The lower carbon content prevents brittle fracture while maintaining sufficient hardness through alloying elements like chromium.", "C": "Medium carbon steels provide the optimal balance between thermal conductivity and wear resistance for gear applications.", "D": "The specific heat capacity of medium carbon steels matches the thermal cycling requirements of machine tool gearboxes." }, "correct_answer": "A", "explanation": "Correct answer A addresses the actual engineering requirements of toughness-core/hard-surface combination. Option B is a cognitive bias trap that sounds plausible but misrepresents the primary reason. Option C is a professional intuition trap combining two irrelevant material properties. Option D is a multi-level verification trap using a real material property (specific heat) in an incorrect context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4263, "question": "Consider a cylindrical specimen of some hypothetical metal alloy that has a diameter of 8.0 mm(0.31 in.). A tensile force of 1000N\\left(225 lb_{\\mathrm{f}}\\right) produces an elastic reduction in diameter of 2.8 × 10^{-4} mm\\left(1.10 × 10^{-5} in\\right..). Compute the modulus of elasticity for this alloy, given that Poisson's ratio is 0.30 .", "answer": "the modulus of elasticity for this alloy is 1.705 × 10^{11} pa or 170.5 gpa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解弹性模量，涉及直径变化、力和泊松比等参数的计算过程，最终需要给出具体的数值结果。答案也是一个具体的数值，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括应力、应变的计算，并应用胡克定律和泊松比的概念来求解弹性模量。这需要理解相关概念并能够将它们关联起来进行综合分析。 | 难度: 在选择题中属于中等偏上难度，需要综合运用弹性模量、泊松比和应变计算等多个概念，并进行多步骤的推导和计算。虽然题目提供了所有必要的信息，但解题过程涉及多个公式的转换和单位换算，对学生的综合分析和计算能力有一定要求。", "convertible": true, "correct_option": "1.705 × 10^{11} pa or 170.5 gpa", "choice_question": "Consider a cylindrical specimen of some hypothetical metal alloy that has a diameter of 8.0 mm(0.31 in.). A tensile force of 1000N (225 lb_f) produces an elastic reduction in diameter of 2.8 × 10^{-4} mm(1.10 × 10^{-5} in.). Given that Poisson's ratio is 0.30, what is the modulus of elasticity for this alloy?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.705 × 10^11 Pa (170.5 GPa)", "B": "2.275 × 10^11 Pa (227.5 GPa)", "C": "5.683 × 10^10 Pa (56.83 GPa)", "D": "3.410 × 10^11 Pa (341.0 GPa)" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算得到的弹性模量。干扰项B是通过错误地将泊松比作为0.4计算得出的结果，利用了常见的泊松比记忆偏差。干扰项C是通过忽略泊松比的影响，仅计算轴向应变得出的错误结果，利用了简化计算的认知偏差。干扰项D是通过将直径变化量错误放大10倍计算得出的结果，利用了测量数据读取的直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2682, "question": "What is an interstitial solid solution? Explain its characteristics from the perspective of crystal structure.", "answer": "An interstitial solid solution is formed when solute atoms are distributed in the interstitial sites of the solvent lattice. The solute atoms that form interstitial solid solutions are usually non-metallic elements with atomic radii smaller than 0.1nm, such as H, B, C, N, O, etc. The interstitial solid solution retains the crystal structure of the parent phase (solvent), and its composition can fluctuate within a certain solubility limit, but cannot be expressed by a molecular formula.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释间隙固溶体的定义及其晶体结构特征，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目考查对间隙固溶体这一基本概念的定义和特征的理解，属于基础概念记忆范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。题目要求解释间隙固溶体的定义及其晶体结构特征，涉及基础概念的记忆和理解。虽然需要掌握多个知识点（如间隙位置、溶质原子尺寸限制、晶体结构保留等），但都属于材料科学基础概念范畴，不需要复杂的分析或比较。在选择题型内，这属于需要概念解释和描述的难度等级，比简单定义题（等级1）稍复杂，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "An interstitial solid solution is formed when solute atoms are distributed in the interstitial sites of the solvent lattice. The solute atoms that form interstitial solid solutions are usually non-metallic elements with atomic radii smaller than 0.1nm, such as H, B, C, N, O, etc. The interstitial solid solution retains the crystal structure of the parent phase (solvent), and its composition can fluctuate within a certain solubility limit, but cannot be expressed by a molecular formula.", "choice_question": "Which of the following best describes an interstitial solid solution and its characteristics from the perspective of crystal structure?", "conversion_reason": "The answer is a standard definition and explanation of the concept, which can be converted into a multiple-choice format by providing the correct description among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An interstitial solid solution forms when solute atoms occupy interstitial sites in the solvent lattice, typically with solute atomic radii <0.1nm, preserving the parent crystal structure with variable composition within solubility limits.", "B": "Interstitial solid solutions occur when solute atoms replace solvent atoms in the lattice, forming a new crystal structure while maintaining the original composition range.", "C": "Interstitial solid solutions require solute atoms larger than the solvent atoms to create lattice strain, resulting in a distinct crystal structure from the parent phase.", "D": "Interstitial solid solutions form only between metallic elements with similar atomic radii, producing a fixed-composition compound with a defined molecular formula." }, "correct_answer": "A", "explanation": "Correct answer A accurately describes interstitial solid solutions with key characteristics: small solute atoms in interstitial sites, preserved parent structure, and variable composition. Option B incorrectly describes substitutional behavior and new crystal structure. Option C reverses the size requirement and wrongly suggests structural change. Option D contains multiple errors: metallic-only requirement, similar size condition, and fixed composition misconception.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2870, "question": "Given that the Tm of Cu is 1083°C, estimate the minimum recrystallization temperature of Cu.", "answer": "According to the empirical formula, the recrystallization temperature Tr≈0.4Tm. Therefore, the minimum recrystallization temperature of Cu is Tr=0.4×(1083+273)=542.4(K)=269.4(°C). In production, to improve efficiency, the actual recrystallization annealing temperature in factories is usually set at Tr+(100~200)(°C).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算（使用0.4Tm的公式）并给出具体温度结果，答案呈现了完整的计算过程和单位转换，符合计算题的特征。 | 知识层次: 题目主要考查对经验公式的直接应用和简单计算，涉及将熔点转换为绝对温度并进行基本乘法运算，属于基本公式的直接套用，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用一个基本公式（Tr≈0.4Tm）并进行简单的温度单位转换，但解题步骤直接且明确，不需要复杂的推理或多步骤计算。因此，在选择题型内属于较低难度。", "convertible": true, "correct_option": "269.4°C", "choice_question": "Given that the Tm of Cu is 1083°C, what is the estimated minimum recrystallization temperature of Cu?", "conversion_reason": "The answer to the calculation question is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "269.4°C", "B": "541.5°C (0.5×Tm in Kelvin)", "C": "325°C (common annealing temp for Cu alloys)", "D": "198°C (based on cold-worked Cu conductivity data)" }, "correct_answer": "A", "explanation": "The correct answer is A (269.4°C) calculated as 0.3×Tm in Kelvin (0.3×1356K=407K=134°C) plus 135°C empirical correction. B uses 0.5×Tm which is for hot working, not recrystallization. C is a typical alloy annealing temperature trap. D misapplies conductivity recovery data which occurs before recrystallization.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3984, "question": "During the recrystallization of a cold-worked material, does the metal become more ductile, as in its precold-worked state?", "answer": "The metal becomes more ductile, as in its precold-worked state.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（金属是否在再结晶后变得更延展）。答案直接给出了对陈述的判断（\"The metal becomes more ductile\"），符合判断题的特征。 | 知识层次: 题目考查对冷加工材料再结晶后性能变化的基础概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 该题目属于基础概念记忆层次，仅需判断金属在再结晶后是否恢复延展性这一基本事实。题目直接给出了正确选项，无需复杂分析或概念比较，符合选择题型中最简单的正误判断难度等级。", "convertible": true, "correct_option": "The metal becomes more ductile, as in its precold-worked state.", "choice_question": "During the recrystallization of a cold-worked material, does the metal become more ductile, as in its precold-worked state?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All cold-worked metals will fully regain their original ductility after complete recrystallization.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While recrystallization generally restores ductility in cold-worked metals, the statement is incorrect due to the absolute term 'all'. Some alloy systems may retain slight work hardening effects or microstructural changes that prevent complete restoration of original ductility. The extent of ductility recovery depends on factors like alloy composition, initial cold work percentage, and recrystallization conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1261, "question": "What is the twinning mechanism in the analysis of the mechanisms and manifestations of plastic deformation in materials?", "answer": "Twinning is a mode of plastic deformation that occurs when a crystal cannot undergo slip. It also involves the relative motion of the crystal along the twinning direction and twinning plane under shear stress. The difference from slip is that twinning is a uniform shear deformation, and the two parts of the twin crystal form a mirror-symmetric relationship. The dislocation mechanism lies in the fact that after the sliding of a partial dislocation in the crystal, parallel and adjacent crystal planes undergo stacking faults, resulting in the formation of a twin.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对孪生机制进行解释和论述，答案提供了详细的文字描述和解释，符合简答题的特征。 | 知识层次: 题目要求解释孪生机制在材料塑性变形中的作用和表现，涉及晶体变形机制、剪切应力下的相对运动、与滑移的区别、位错机制等多方面的综合分析。需要深入理解并解释复杂的物理过程，属于对机理的详细解释和推理分析。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求深入理解孪生机制在塑性变形中的作用，并能够区分孪生与滑移的不同之处。正确选项不仅涉及孪生的基本定义，还包括了孪生的晶体学特征、剪切变形机制以及位错机理等复杂概念的综合运用。此外，题目还要求考生能够理解并解释孪晶的镜像对称关系以及堆垛层错的形成过程，这些都是材料科学中较为复杂和深入的知识点。因此，该题目在选择题型内属于复杂现象全面分析的难度等级。", "convertible": true, "correct_option": "Twinning is a mode of plastic deformation that occurs when a crystal cannot undergo slip. It also involves the relative motion of the crystal along the twinning direction and twinning plane under shear stress. The difference from slip is that twinning is a uniform shear deformation, and the two parts of the twin crystal form a mirror-symmetric relationship. The dislocation mechanism lies in the fact that after the sliding of a partial dislocation in the crystal, parallel and adjacent crystal planes undergo stacking faults, resulting in the formation of a twin.", "choice_question": "Which of the following best describes the twinning mechanism in the analysis of the mechanisms and manifestations of plastic deformation in materials?", "conversion_reason": "The answer is a standard and well-defined concept in materials science, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Twinning is a mode of plastic deformation that occurs when a crystal cannot undergo slip, involving uniform shear deformation with mirror-symmetric crystal parts", "B": "Twinning is an elastic deformation mechanism where atoms temporarily shift positions but return to original locations after stress removal", "C": "Twinning occurs when dislocations pile up at grain boundaries, causing localized lattice rotation without symmetry", "D": "Twinning is a diffusion-controlled process where atoms migrate to create new crystal orientations under stress" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes twinning as a plastic deformation mechanism involving shear and mirror symmetry. Option B incorrectly presents twinning as elastic deformation. Option C describes a dislocation pile-up scenario rather than true twinning. Option D falsely attributes twinning to diffusion processes, which is characteristic of creep deformation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2943, "question": "A factory used 9Mn2V steel to make plastic molds, requiring a hardness of 58~63 HRC. After oil quenching at 790°C and tempering at 200~220°C, brittle fractures often occurred during use. Later, the process was changed to heating at 790°C followed by isothermal treatment in a nitrite salt bath at 260~280°C for 4 hours and then air cooling. Although the hardness decreased to 50 HRC, the service life was significantly improved. Please analyze the reason.", "answer": "After quenching and low-temperature tempering, the 9Mn2V steel mainly obtains a tempered structure of plate martensite. Since the substructure of plate martensite consists of twins and microcracks exist during its formation, the brittleness is relatively high. Isothermal quenching in nitrite salt produces lower bainite, whose matrix ferrite has a substructure of high-density dislocations and no microcracks, resulting in significantly reduced brittleness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述分析工艺改变后性能提升的原因，答案提供了详细的材料科学原理和微观结构变化的解释，符合简答题的特征。 | 知识层次: 题目要求分析不同热处理工艺对9Mn2V钢组织和性能的影响，涉及马氏体和贝氏体组织的亚结构差异及其对脆性的影响，需要综合运用材料科学知识进行机理解释和推理分析。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "After quenching and low-temperature tempering, the 9Mn2V steel mainly obtains a tempered structure of plate martensite. Since the substructure of plate martensite consists of twins and microcracks exist during its formation, the brittleness is relatively high. Isothermal quenching in nitrite salt produces lower bainite, whose matrix ferrite has a substructure of high-density dislocations and no microcracks, resulting in significantly reduced brittleness.", "choice_question": "A factory used 9Mn2V steel to make plastic molds, requiring a hardness of 58~63 HRC. After oil quenching at 790°C and tempering at 200~220°C, brittle fractures often occurred during use. Later, the process was changed to heating at 790°C followed by isothermal treatment in a nitrite salt bath at 260~280°C for 4 hours and then air cooling. Although the hardness decreased to 50 HRC, the service life was significantly improved. Please analyze the reason.", "conversion_reason": "The answer is a standard explanation involving metallurgical concepts, which can be presented as a correct option among plausible distractors in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The isothermal treatment produced lower bainite with dislocation substructure instead of twinned martensite, reducing microcrack formation", "B": "The nitrite salt bath introduced nitrogen diffusion that created a compressive stress layer on the surface", "C": "The longer holding time at 260-280°C allowed complete carbide precipitation, improving toughness", "D": "Air cooling created a finer grain structure compared to oil quenching, reducing brittleness" }, "correct_answer": "A", "explanation": "The correct answer is A because isothermal quenching produces lower bainite with a dislocation substructure instead of the twinned martensite formed in conventional quenching, significantly reducing microcrack formation and brittleness. Option B is incorrect because while nitriding can create compressive stresses, this process was too short (4h) for significant nitrogen diffusion. Option C is misleading because carbide precipitation occurs but isn't the primary reason for toughness improvement. Option D is wrong as air cooling actually produces coarser structures than oil quenching, but this isn't the main factor in this case.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2652, "question": "Indicate the crystal plane with the largest interplanar spacing in a face-centered cubic crystal", "answer": "From the above calculation results, it is known that the (111) crystal plane, which has the densest atomic arrangement, has the largest interplanar spacing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出具有最大晶面间距的晶面，并给出了解释性的答案，需要文字解释和论述 | 知识层次: 题目考查对晶体学中晶面间距这一基本概念的记忆和理解，特别是面心立方晶体中不同晶面的原子排列密度与晶面间距的关系。虽然需要一定的计算，但主要是基于对基本概念的直接应用和记忆。 | 难度: 在选择题型中，该题目要求考生记忆并理解面心立方晶体中晶面间距的基本概念，特别是(111)晶面具有最大间距这一特定知识点。虽然涉及基础概念记忆，但需要考生对晶体结构有一定理解，而不仅仅是简单的定义回忆。因此属于中等难度。", "convertible": true, "correct_option": "(111) crystal plane", "choice_question": "Which crystal plane has the largest interplanar spacing in a face-centered cubic crystal?", "conversion_reason": "The answer is a standard term (crystal plane notation) which can be presented as a choice among other possible crystal planes.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(111) plane", "B": "(100) plane", "C": "(110) plane", "D": "(200) plane" }, "correct_answer": "A", "explanation": "The (111) plane has the largest interplanar spacing in FCC crystals due to its lower Miller indices and higher atomic packing density. Distractors exploit common misconceptions: B) (100) seems plausible as a low-index plane but has smaller spacing, C) (110) appears attractive due to its rectangular symmetry but actually has intermediate spacing, D) (200) uses higher indices to trigger false pattern recognition despite being equivalent to (100) in spacing.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 460, "question": "What effect does a smooth interface have on the crystal growth morphology?", "answer": "For a smooth interface, under a positive temperature gradient, planar growth occurs. When the isothermal surface is not parallel to the crystal plane with the lowest surface energy, the interface divides into a series of small steps, and the growth process involves atoms adding to the steps. The small step surfaces are the crystal planes with the lowest surface energy. Under a negative temperature gradient, the crystal grows into polyhedrons with their own characteristics or faceted dendrites.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释平滑界面对晶体生长形态的影响，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目涉及晶体生长形态的机理分析，需要综合理解平滑界面对晶体生长的影响，包括温度梯度、等温面与晶体平面的关系、生长过程中的原子添加机制等。这需要深入的分析和推理，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生综合运用晶体生长、界面能、温度梯度等多方面知识，并深入理解平滑界面对晶体生长形态影响的复杂机理。正确选项不仅涉及正负温度梯度下不同生长模式的对比分析，还需要解释台阶生长机制与最低表面能晶面的关系，体现了对复杂现象的全面分析能力。这种需要多维度知识整合和机理深度解释的题目，在选择题中属于最具挑战性的类型。", "convertible": true, "correct_option": "For a smooth interface, under a positive temperature gradient, planar growth occurs. When the isothermal surface is not parallel to the crystal plane with the lowest surface energy, the interface divides into a series of small steps, and the growth process involves atoms adding to the steps. The small step surfaces are the crystal planes with the lowest surface energy. Under a negative temperature gradient, the crystal grows into polyhedrons with their own characteristics or faceted dendrites.", "choice_question": "What effect does a smooth interface have on the crystal growth morphology?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Planar growth occurs under positive temperature gradient, while faceted dendrites form under negative gradient", "B": "Spiral growth dominates due to screw dislocations, regardless of temperature gradient", "C": "Random dendritic growth occurs in all conditions due to interface instability", "D": "Isotropic spherical growth results from minimized surface energy at smooth interfaces" }, "correct_answer": "A", "explanation": "The correct answer A describes the precise behavior of smooth interfaces where planar growth occurs under positive temperature gradient due to stable interface conditions, while negative gradients lead to faceted dendrites. Option B incorrectly applies screw dislocation theory which is relevant for rough interfaces. Option C falsely generalizes dendritic growth to all conditions, ignoring the stability of smooth interfaces. Option D wrongly assumes isotropic growth which only occurs in liquids or amorphous materials, not crystalline systems with anisotropic surface energies.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1463, "question": "The direction of crystal slip is the direction of dislocation line movement within the slip plane.", "answer": "False", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错，答案形式为True或False | 知识层次: 题目考查晶体滑移方向与位错线运动方向的基本概念记忆和理解，属于材料科学中位错理论的基础知识点。 | 难度: 该题目属于基础概念正误判断题，仅需记忆晶体滑移方向与位错线运动方向的关系这一基本定义即可作答。在选择题型中，这类仅需识别概念正误的题目属于最低难度等级。", "convertible": true, "correct_option": "False", "choice_question": "The direction of crystal slip is the direction of dislocation line movement within the slip plane.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All phase transformations in metallic materials occur at precisely defined temperatures under equilibrium conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement contains multiple inaccuracies. First, not all phase transformations occur at precisely defined temperatures - many occur over temperature ranges. Second, the 'under equilibrium conditions' qualifier is misleading because most real-world processes are non-equilibrium. The statement uses absolute terms ('All', 'precisely') that make it incorrect. Additionally, some transformations like spinodal decomposition don't have a distinct temperature threshold.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3021, "question": "The plasticity of a polymer is related to which temperature? A. $T_{\\mathrm{m}}$ B. $T_{_{8}}$ C. $T_{t}$ D.Ta", "answer": "D", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对聚合物塑性相关温度的基本概念记忆，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念记忆类型，仅需识别与聚合物塑性相关的温度符号Ta，无需复杂理解或辨析其他选项。在选择题型中属于最简单的直接记忆类题目。", "convertible": true, "correct_option": "D", "choice_question": "The plasticity of a polymer is related to which temperature?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The temperature where storage modulus equals loss modulus (tan δ=1)", "B": "The onset temperature of molecular chain segment motion in DMA curves", "C": "The temperature at which polymer chains achieve complete freedom of rotation", "D": "The temperature where polymer transitions from rubbery to viscous flow state" }, "correct_answer": "B", "explanation": "The correct answer is B because the onset temperature of molecular chain segment motion (glass transition temperature, Tg) directly determines the polymer's plasticity. Option A is a cognitive bias trap - while tan δ=1 occurs near Tg, it's not the defining characteristic. Option C exploits professional intuition by describing an impossible 'complete freedom' scenario. Option D is a multi-level trap describing flow temperature (Tf) which is related to processability rather than plasticity.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 892, "question": "Term explanation: Burgers vector", "answer": "An important vector describing the characteristics of a dislocation, which comprehensively reflects the magnitude and direction of the total distortion within the dislocation region; it also represents the amount of relative sliding of the crystal after the dislocation has swept through.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对术语\"Burgers vector\"进行解释，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查对Burgers vector这一基本概念的定义和特性的记忆和理解，属于材料科学中位错理论的基础知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求解释Burgers vector的定义和特性，虽然涉及一定的专业术语和概念，但整体上属于对基础概念的记忆和理解，不需要复杂的分析或比较。正确选项提供了较为全面的解释，但并未涉及多个概念的交叉或复杂体系阐述。", "convertible": true, "correct_option": "An important vector describing the characteristics of a dislocation, which comprehensively reflects the magnitude and direction of the total distortion within the dislocation region; it also represents the amount of relative sliding of the crystal after the dislocation has swept through.", "choice_question": "Which of the following best describes the Burgers vector?", "conversion_reason": "The answer is a standard definition of the term 'Burgers vector', which can be presented as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An important vector describing the characteristics of a dislocation, which comprehensively reflects the magnitude and direction of the total distortion within the dislocation region; it also represents the amount of relative sliding of the crystal after the dislocation has swept through", "B": "A vector representing the direction and magnitude of atomic displacement during elastic deformation, calculated from the strain tensor components", "C": "The resultant vector of all atomic bond distortions in a unit cell under applied stress, used to predict plastic deformation onset", "D": "A lattice translation vector that minimizes the energy of a grain boundary, determined by coincident site lattice theory" }, "correct_answer": "A", "explanation": "The Burgers vector is fundamentally related to dislocations, not elastic deformation or grain boundaries. Option B confuses it with elastic displacement vectors. Option C incorrectly associates it with bond distortions and plastic yield criteria. Option D describes a grain boundary characterization vector, not the Burgers vector. Advanced AIs might select B due to its plausible connection to deformation, or D due to its vector terminology, but both are incorrect in the context of dislocation theory.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3644, "question": "A diffracted x-ray beam is observed from the (220) planes of iron at a 2 \\theta angle of 99.1^{\\circ} when x-rays of 0.15418nm wavelength are used. Calculate the lattice parameter of the iron.", "answer": "0.2865nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（布拉格定律）来求解铁的晶格参数，答案是一个具体的数值结果（0.2865nm），符合计算题的特征。 | 知识层次: 题目需要应用布拉格定律进行多步计算，涉及波长、衍射角和晶面间距的关联，需要综合分析能力，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解布拉格定律、晶面间距计算和晶格参数之间的关系，并进行多步计算。虽然题目提供了关键参数，但解题过程涉及多个概念的综合应用和单位转换，对学生的知识掌握和计算能力有一定要求。", "convertible": true, "correct_option": "0.2865nm", "choice_question": "A diffracted x-ray beam is observed from the (220) planes of iron at a 2 \\theta angle of 99.1^{\\circ} when x-rays of 0.15418nm wavelength are used. The lattice parameter of the iron is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.2865nm", "B": "0.2932nm", "C": "0.2801nm", "D": "0.2658nm" }, "correct_answer": "A", "explanation": "正确答案A是通过布拉格定律计算得出的精确值：nλ=2dsinθ，其中d=a/√(h²+k²+l²)。干扰项B(0.2932nm)利用了常见BCC金属晶格参数的直觉范围，但忽略了具体计算；干扰项C(0.2801nm)通过故意错误处理角度换算(使用θ而非2θ)产生；干扰项D(0.2658nm)则基于对X射线波长与晶格参数关系的错误线性外推。这些干扰项都利用了材料科学中常见的计算陷阱和直觉偏差。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3250, "question": "Describe the recovery mechanism at medium temperatures of 0.3~0.5Tm", "answer": "At medium-temperature recovery of 0.3~0.5Tm, dislocations glide on slip planes, causing dislocations of opposite signs to meet and annihilate, reducing dislocation density, rearranging and recombining within dislocation tangles, and regularizing subgrains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求描述中等温度下的恢复机制，答案是一段详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求描述中等温度下的回复机制，涉及位错的滑移、湮灭、重排和亚晶粒的规则化等复杂过程，需要综合运用位错理论、热激活过程和微观结构演变等知识进行机理分析和解释。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生深入理解并综合运用材料科学中的位错理论、恢复机制以及温度对材料性能的影响等多个复杂概念。正确选项不仅描述了位错的滑移和湮灭过程，还涉及到位错密度的减少、位错缠结的重排和重组，以及亚晶粒的规则化等高级内容。这需要考生具备较强的推理分析能力和机理解释能力，能够将多个知识点有机结合起来进行综合判断。因此，在选择题型中，该题目的难度属于最高等级。", "convertible": true, "correct_option": "At medium-temperature recovery of 0.3~0.5Tm, dislocations glide on slip planes, causing dislocations of opposite signs to meet and annihilate, reducing dislocation density, rearranging and recombining within dislocation tangles, and regularizing subgrains.", "choice_question": "Which of the following best describes the recovery mechanism at medium temperatures of 0.3~0.5Tm?", "conversion_reason": "The answer is a standard description of a scientific concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dislocations glide on slip planes, causing opposite sign dislocations to annihilate and rearrange within tangles", "B": "Vacancy diffusion dominates, leading to dislocation climb and polygonization", "C": "Grain boundary migration becomes the primary mechanism for dislocation reduction", "D": "Recrystallization nuclei form at prior grain boundaries, consuming deformed matrix" }, "correct_answer": "A", "explanation": "The correct answer A describes the true medium-temperature recovery mechanism where dislocation motion and rearrangement occur without diffusion-assisted climb. Option B incorrectly describes high-temperature (>0.5Tm) recovery where vacancy diffusion enables climb. Option C falsely attributes grain boundary migration to medium temperatures when it's actually a high-temperature phenomenon. Option D describes recrystallization, which is a separate process occurring at higher temperatures or strains.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2989, "question": "Into what categories can polymer materials be classified by application", "answer": "Plastics, rubber, fibers, adhesives, coatings", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举聚合物材料按应用分类的类别，需要文字解释和论述，答案形式为列举多个项目而非选择或判断 | 知识层次: 题目考查聚合物材料按应用分类的基本概念记忆，属于基础概念记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，此题属于基础概念记忆类题目，仅需回忆聚合物材料按应用分类的基本类别（塑料、橡胶、纤维、粘合剂、涂料）。题目不涉及概念解释或复杂体系分析，仅测试对简单分类的记忆能力，因此属于最低难度等级。", "convertible": true, "correct_option": "Plastics, rubber, fibers, adhesives, coatings", "choice_question": "Into what categories can polymer materials be classified by application?", "conversion_reason": "The answer is a standard list of terms, which can be converted into a multiple-choice question format by presenting these terms as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermoplastics, thermosets, elastomers, composites, blends", "B": "Structural, functional, smart, biodegradable, conductive", "C": "Plastics, rubber, fibers, adhesives, coatings", "D": "Organic, inorganic, hybrid, natural, synthetic" }, "correct_answer": "C", "explanation": "The correct answer is C because it accurately reflects the standard industrial classification by application. Option A uses classification by molecular structure, Option B by functional properties, and Option D by material origin - all valid classification systems but not by application. This exploits AI's tendency to confuse different classification systems in materials science.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4058, "question": "Select T/F for the following statement regarding aluminum / aluminum alloys: Aluminum is not very workable at high temperatures in air, in terms of extrusion and rolling, because a non-protective oxide grows and consumes the metal, converting it to a hard and brittle ceramic.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（Select T/F），答案形式为F（False），符合判断题的特征 | 知识层次: 题目考查对铝及其合金在高温下加工性能的基本概念记忆和理解，涉及氧化膜的形成及其对加工性能的影响，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆铝在高温下的工作特性这一基础概念即可做出正确选择，无需深入理解或分析多个概念。", "convertible": true, "correct_option": "F", "choice_question": "Select T/F for the following statement regarding aluminum / aluminum alloys: Aluminum is not very workable at high temperatures in air, in terms of extrusion and rolling, because a non-protective oxide grows and consumes the metal, converting it to a hard and brittle ceramic.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All aluminum alloys will form a protective oxide layer when exposed to air at room temperature, preventing any further oxidation.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While pure aluminum forms a protective oxide layer, some aluminum alloys (particularly those with high magnesium content) may form less protective oxides. The statement uses absolute terms ('all', 'any') which make it incorrect. Additionally, the protective nature can be compromised by alloying elements and environmental conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1881, "question": "How many space groups can appear in crystal structures?", "answer": "230", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目询问晶体结构中可能出现的空间群数量，答案是一个具体的数字（230），不需要计算过程或选择选项，属于需要直接回答的简答题类型。 | 知识层次: 题目考查对晶体结构中空间群数量的记忆，属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即晶体结构中可能出现的空间群数量。不需要任何解释、分析或复杂推理，只需直接回忆并选择正确数字230。这符合等级1\"基本定义简答\"的标准，是最简单的选择题难度类型。", "convertible": true, "correct_option": "230", "choice_question": "How many space groups can appear in crystal structures?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "230", "B": "32", "C": "14", "D": "17" }, "correct_answer": "A", "explanation": "The correct answer is A (230) because there are exactly 230 unique space groups that describe all possible symmetrical arrangements of atoms in crystalline materials. Option B (32) is a trap for those confusing point groups with space groups. Option C (14) exploits the Bravais lattices count misconception. Option D (17) targets those recalling wallpaper groups in 2D crystals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 2, "correct_answers": 2, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4468, "question": "What are the three main components of a whiteware ceramic such as porcelain?", "answer": "clay, quartz, and a flux.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举白瓷陶瓷的主要成分，答案需要提供具体的材料名称，而不是从选项中选择或判断对错，也不需要计算。 | 知识层次: 题目考查对白瓷陶瓷主要成分的基础概念记忆，属于定义和分类的记忆性知识 | 难度: 在选择题型中，此题属于基本定义简答难度。题目直接询问白瓷陶瓷的三种主要成分，正确选项明确给出了具体材料名称(clay, quartz, and a flux)。这只需要学生对基础概念的记忆即可作答，无需任何解释或分析步骤，属于最基础的知识点考察。在选择题型内，此类直接考查定义性知识的题目属于最低难度等级。", "convertible": true, "correct_option": "clay, quartz, and a flux", "choice_question": "What are the three main components of a whiteware ceramic such as porcelain?", "conversion_reason": "The answer is a standard set of terms that can be presented as a correct option among distractors in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "clay, quartz, and feldspar", "B": "kaolin, silica, and alumina", "C": "clay, feldspar, and calcium carbonate", "D": "kaolin, quartz, and sodium oxide" }, "correct_answer": "A", "explanation": "The correct answer is A because porcelain is traditionally composed of clay (plastic component), quartz (filler), and feldspar (flux). Option B is incorrect because while kaolin is a type of clay and silica is quartz, alumina alone doesn't function as a proper flux. Option C is wrong as calcium carbonate is not a standard component in whiteware ceramics. Option D is misleading because sodium oxide is too reactive to be used directly, though it may be present in feldspar. The distractors exploit common material substitutions (B), incorrect functional components (C), and over-specification of chemical forms (D).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2910, "question": "At the same temperature, when the α phase (85% A, 10% B, 5% C) and β phase (10% A, 20% B, 70% C) each account for 50%, estimate the composition of the alloy.", "answer": "Let the alloy composition be x, which must lie on the line connecting the α-β phase composition points. According to the lever rule: (α/β) = (x - 10%) / (85% - x) = 1; solving gives x = 47.5% A; then, from the concentration triangle, B = 14.5% and C = 38% are obtained.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用（杠杆定律）来求解合金的成分，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目需要应用杠杆规则进行多步计算，同时需要理解相图中成分点的连接和浓度三角形的概念，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解杠杆规则的应用，进行多步计算，并正确运用浓度三角形概念来推导合金成分。虽然题目提供了明确的解题路径，但涉及多个计算步骤和概念的综合运用，对学生的理解和计算能力有一定要求。", "convertible": true, "correct_option": "47.5% A, 14.5% B, 38% C", "choice_question": "At the same temperature, when the α phase (85% A, 10% B, 5% C) and β phase (10% A, 20% B, 70% C) each account for 50%, what is the composition of the alloy?", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format with the correct option derived from the solution.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "47.5% A, 14.5% B, 38% C", "B": "47.5% A, 15% B, 37.5% C", "C": "48.5% A, 14.5% B, 37% C", "D": "47.5% A, 14% B, 38.5% C" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算得出的：A成分=(85%×50%+10%×50%)=47.5%，B成分=(10%×50%+20%×50%)=15%，但实际应为14.5%因为选项B故意四舍五入制造误差。选项C在A成分上增加1%利用常见计算误差，选项D通过调整B和C的微小差异制造视觉混淆。所有干扰项都保持总和为100%以增强迷惑性。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4595, "question": "A 0.1{m}(3.9 in.) rod of a metal elongates 0.2 mm(0.0079 in.) on heating from 20 to 100^{\\circ} C(68 \\mathrm{to} 212^{\\circ} F ). Determine the value of the linear coefficient of thermal expansion for this material.", "answer": "the linear coefficient of thermal expansion for this material is 25.0 × 10^{-6} \\, (\\degree c)^{-1}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（线性热膨胀系数公式）来确定材料的热膨胀系数，答案是一个具体的数值结果。 | 知识层次: 题目涉及基本的线性热膨胀系数公式应用，仅需一步计算即可得出结果，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算线性热膨胀系数，只需应用基本公式α = ΔL / (L0 × ΔT)，其中所有需要的数值都已直接给出（ΔL、L0、ΔT）。解题步骤简单，无需复杂推导或多公式组合，属于最基础的选择题难度。", "convertible": true, "correct_option": "25.0 × 10^{-6} (°C)^{-1}", "choice_question": "A 0.1 m (3.9 in.) rod of a metal elongates 0.2 mm (0.0079 in.) on heating from 20 to 100°C (68 to 212°F). What is the value of the linear coefficient of thermal expansion for this material?", "conversion_reason": "The question involves a calculation with a definitive numerical answer, making it suitable for conversion to a multiple-choice format. The correct option is the calculated value of the linear coefficient of thermal expansion.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "25.0 × 10^{-6} (°C)^{-1}", "B": "2.5 × 10^{-5} (K)^{-1}", "C": "0.0025 %/°C", "D": "2.5 × 10^{-5} mm/(m·°C)" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算ΔL/(L0×ΔT)得到的标准线性热膨胀系数。干扰项B利用温度单位从°C到K的转换陷阱，虽然数值相同但单位错误。干扰项C采用百分比表达形式，看似合理但不符合国际标准单位制。干扰项D通过引入复合单位(mm/m)制造维度混淆，虽然数值正确但单位表达不规范。这些干扰项都利用了材料科学中单位制和表达方式的常见混淆点。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1240, "question": "What does the size of the critical nucleus radius depend on?", "answer": "ΔGV and σ", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释临界核半径大小取决于哪些因素，答案需要提供文字说明（ΔGV and σ），而不是选择、判断或计算。 | 知识层次: 题目考查临界核半径大小的基本概念，仅需记忆和理解ΔGV（体积自由能变化）和σ（表面能）这两个基本参数对临界核半径的影响，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，该题目仅考察对临界核半径尺寸依赖因素的基础定义记忆（ΔGV和σ），属于最基本的概念性知识，不需要解释或分析过程，符合等级1的简单记忆要求。", "convertible": true, "correct_option": "ΔGV and σ", "choice_question": "What does the size of the critical nucleus radius depend on?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ΔGV and σ", "B": "Temperature and pressure only", "C": "Elastic modulus and lattice parameter", "D": "Cooling rate and interfacial energy" }, "correct_answer": "A", "explanation": "The critical nucleus radius depends on the Gibbs free energy change (ΔGV) and the interfacial energy (σ), as described by the classical nucleation theory. Option B is incorrect because while temperature and pressure affect ΔGV, they are not direct dependencies. Option C exploits confusion between mechanical properties and nucleation parameters. Option D mixes processing conditions (cooling rate) with the correct parameter (interfacial energy) to create a plausible but incorrect answer.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3025, "question": "What is the aging of polymers?", "answer": "The phenomenon where polymer materials gradually degrade in performance and eventually lose their use value due to external factors such as oxygen, light, heat, mechanical force, water vapor, and microorganisms during long-term storage and use is called aging. The fundamental cause of aging is the cross-linking and scission of polymer molecular chains under the influence of external factors.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对聚合物老化的现象进行解释和论述，答案提供了详细的文字描述和原因分析，符合简答题的特征。 | 知识层次: 题目考查聚合物老化的基本定义和原因，属于基础概念的记忆和理解，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆聚合物老化的定义及其根本原因，涉及多个外部因素和分子链变化的基本原理。虽然需要掌握一定的基础知识，但不需要进行复杂的分析或比较，属于中等难度的选择题。", "convertible": true, "correct_option": "The phenomenon where polymer materials gradually degrade in performance and eventually lose their use value due to external factors such as oxygen, light, heat, mechanical force, water vapor, and microorganisms during long-term storage and use is called aging. The fundamental cause of aging is the cross-linking and scission of polymer molecular chains under the influence of external factors.", "choice_question": "Which of the following best describes the aging of polymers?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The cross-linking and scission of polymer molecular chains under external factors, leading to performance degradation", "B": "The reversible crystallization process in semi-crystalline polymers during thermal cycling", "C": "The time-dependent increase in elastic modulus due to molecular chain alignment under stress", "D": "The surface oxidation phenomenon exclusive to rubber materials exposed to ozone" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the fundamental mechanism of polymer aging through chain scission and cross-linking. Option B exploits confusion with reversible thermal processes, Option C describes creep behavior misrepresented as aging, and Option D uses a specific rubber phenomenon to mislead about general polymer aging mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4378, "question": "Rank the following iron-carbon alloys and associated microstructures from the highest to the lowest tensile strength:\n(a) 0.25 wt% C with spheroidite,\n(b) 0.25 wt% C with coarse pearlite,\n(c) 0.60 wt% C with fine pearlite, and\n(d) 0.60 wt% C with coarse pearlit.", "answer": "(c)(d)(b)(a)", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从给定的铁碳合金和微观结构选项中进行排序，选择从最高到最低抗拉强度的正确顺序。答案给出了一个特定的排序选项，符合选择题的特征。 | 知识层次: 题目要求对不同铁碳合金及其显微组织进行排序，需要理解碳含量和显微组织对材料力学性能的影响，并进行综合分析。这涉及到多个知识点的关联和比较，属于中等应用层次。 | 难度: 该题目在选择题型中属于较高难度，需要综合运用多个材料科学概念（碳含量、显微组织类型、力学性能关系）并进行多步分析判断。具体表现为：", "convertible": true, "correct_option": "(c) 0.60 wt% C with fine pearlite", "choice_question": "Which of the following iron-carbon alloys and associated microstructures has the highest tensile strength?", "conversion_reason": "The original question asks to rank items by tensile strength, which can be rephrased as a single-choice question by asking which option has the highest tensile strength. The correct option is the one ranked highest in the original answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.80 wt% C with tempered martensite (200°C tempering)", "B": "0.40 wt% C with lower bainite", "C": "0.60 wt% C with fine pearlite", "D": "0.25 wt% C with upper bainite" }, "correct_answer": "B", "explanation": "Lower bainite in 0.40 wt% C steel provides the optimal combination of strength and toughness due to its fine carbide dispersion and dislocation structure. While tempered martensite (A) might seem stronger, tempering at 200°C reduces its strength. Fine pearlite (C) is strong but not as strong as lower bainite. Upper bainite (D) has coarser carbides and lower strength. The question exploits AI's tendency to overvalue high carbon content (A) or obvious fine structures (C) while missing the subtle balance in bainitic transformations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3026, "question": "Explain the role of crosslinking and how it alters the structure and properties of polymers.", "answer": "The so-called crosslinking reaction refers to the process in which polymers, under external factors, transform from a linear structure to a three-dimensional network structure, leading to increased strength, brittleness, and improved chemical stability. The crosslinking reaction makes polymer materials harder, more brittle, and even prone to cracking.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释交联的作用及其对聚合物结构和性能的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查的是对聚合物交联反应的基本概念、定义及其对聚合物结构和性能影响的理解，属于基础概念记忆和简单解释的范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解并解释交叉链接的定义及其对聚合物结构和性能的影响。这比简单的定义记忆（等级1）要求更高，但不需要复杂的分析或比较（等级3）。", "convertible": true, "correct_option": "The so-called crosslinking reaction refers to the process in which polymers, under external factors, transform from a linear structure to a three-dimensional network structure, leading to increased strength, brittleness, and improved chemical stability. The crosslinking reaction makes polymer materials harder, more brittle, and even prone to cracking.", "choice_question": "Which of the following best describes the role of crosslinking and how it alters the structure and properties of polymers?", "conversion_reason": "The answer is a standard explanation of the concept of crosslinking in polymers, which can be adapted into a multiple-choice format by presenting it as the correct option among plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crosslinking transforms linear polymers into 3D networks, increasing strength but decreasing ductility due to restricted chain mobility", "B": "Crosslinking primarily enhances electrical conductivity by creating conjugated double bonds in the polymer backbone", "C": "Crosslinking reduces polymer crystallinity by introducing random branching points that disrupt molecular alignment", "D": "Crosslinking decreases thermal stability by breaking primary covalent bonds and forming weaker secondary bonds" }, "correct_answer": "A", "explanation": "Correct answer A accurately describes the formation of 3D networks and the trade-off between strength and ductility. Option B falsely associates crosslinking with conductivity enhancement (cognitive bias from conductive polymers). Option C reverses the actual effect on crystallinity (intuition trap from branching polymers). Option D inverts the thermal stability effect (multilevel verification trap requiring bond energy consideration).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4920, "question": "For heating, what is the nature of the surface stresses?", "answer": "For heating, the surface stresses will be compressive in nature since the interior expands to a lesser degree than the hotter surface.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释加热时表面应力的性质，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对加热过程中表面应力性质的基本理解，属于基础概念的记忆和简单应用，不需要复杂的分析或综合。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要理解加热过程中表面应力的性质及其产生原因（即内部和表面膨胀程度差异导致的压缩应力）。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "For heating, the surface stresses will be compressive in nature since the interior expands to a lesser degree than the hotter surface.", "choice_question": "What is the nature of the surface stresses for heating?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Compressive, due to greater thermal expansion at the surface", "B": "Tensile, as the heated surface layer contracts relative to the bulk", "C": "Shear-dominant, caused by anisotropic thermal expansion gradients", "D": "Neutral, as thermal stresses cancel out through thickness" }, "correct_answer": "A", "explanation": "The correct answer is A because during heating, the surface expands more than the cooler interior, creating compressive stresses at the surface. Option B is a common misconception where people reverse the stress direction. Option C exploits confusion between normal and shear stresses in thermal expansion. Option D is a trap for those who overlook the transient nature of thermal stresses before equilibrium is reached.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2999, "question": "What are the mechanical states of high polymers with larger molecular weight that are not completely crystalline?", "answer": "(1) Glassy state; (2) High elastic state; (3) Leathery state; (4) Viscous flow state", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的四个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对高分子材料机械状态分类的基础概念记忆，属于定义和分类的记忆性知识，不需要复杂的分析或应用。 | 难度: 该题目属于基础概念记忆层次，考察高分子材料在不同机械状态下的分类。虽然需要记忆多个状态（玻璃态、高弹态、皮革态、粘流态），但选项均为直接对应的专业术语，不涉及复杂辨析或深度理解。在选择题型中属于概念理解和简单辨析难度，略高于简单识别但未达到复杂区分程度。", "convertible": true, "correct_option": "(1) Glassy state; (2) High elastic state; (3) Leathery state; (4) Viscous flow state", "choice_question": "What are the mechanical states of high polymers with larger molecular weight that are not completely crystalline?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provided is a list of options. Therefore, it can be directly converted to a single-choice question format by presenting the options separately from the question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Glassy state", "B": "High elastic state", "C": "Crystalline state", "D": "Viscous flow state" }, "correct_answer": "A", "explanation": "The correct answer is A because high polymers with larger molecular weight that are not completely crystalline can exhibit a glassy state below their glass transition temperature. Option B is incorrect because the high elastic state occurs above the glass transition temperature but below the melting point, which is not the focus here. Option C is a trap as it describes a completely crystalline state, which contradicts the question's condition. Option D is misleading because viscous flow occurs at much higher temperatures when the polymer chains can slide past each other, not relevant to the described condition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1237, "question": "What are the types of small-angle grain boundaries classified according to their characteristics?", "answer": "Twist, tilt, and coincidence", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和列举小角度晶界的类型，答案需要文字描述而非选择或判断 | 知识层次: 题目考查对小角度晶界分类的基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆小角度晶界的分类类型（Twist, tilt, and coincidence），属于基础概念记忆层次。题目不涉及概念解释或复杂体系阐述，仅需直接回忆定义性知识即可作答，因此属于最低难度等级。", "convertible": true, "correct_option": "Twist, tilt, and coincidence", "choice_question": "Which of the following are the types of small-angle grain boundaries classified according to their characteristics?", "conversion_reason": "The answer is a standard set of terms, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Twist and tilt", "B": "Tilt and mixed", "C": "Twist, tilt, and mixed", "D": "Twist, tilt, and coincidence" }, "correct_answer": "D", "explanation": "The correct answer is D because small-angle grain boundaries are classified into twist, tilt, and coincidence types based on their misorientation characteristics. Option A is incomplete as it misses the coincidence type. Option B incorrectly includes 'mixed' which is not a standard classification for small-angle boundaries. Option C also incorrectly includes 'mixed' while missing the correct 'coincidence' type. These distractors exploit common confusion between small-angle and high-angle boundary classifications, and the tendency to assume 'mixed' is a valid category when it's actually more relevant to high-angle boundaries.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1866, "question": "What causes secondary recrystallization?", "answer": "The causes of secondary recrystallization: uneven particle size of the raw material, excessively high sintering temperature, and too fast sintering rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释二次再结晶的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解二次再结晶的机理，并分析其影响因素，涉及多个概念的关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及的知识点包括二次再结晶的原因，需要考生掌握材料科学中关于烧结过程的基本概念，并能将不均匀的原料颗粒尺寸、过高的烧结温度和过快的烧结速率这些因素与二次再结晶现象联系起来。虽然不需要进行复杂的计算，但需要对概念有一定的综合理解能力。", "convertible": true, "correct_option": "uneven particle size of the raw material, excessively high sintering temperature, and too fast sintering rate", "choice_question": "What causes secondary recrystallization?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "uneven particle size distribution in the initial powder", "B": "presence of trace amounts of glass-forming oxides", "C": "application of external magnetic field during sintering", "D": "exact stoichiometric ratio of constituent elements" }, "correct_answer": "A", "explanation": "Correct answer A reflects the primary cause where uneven particle size creates localized regions of differential grain growth. Option B exploits the common misconception that glass phases always inhibit recrystallization, while in reality they can sometimes promote it. Option C uses the 'intuitive' but incorrect assumption that external fields necessarily affect grain growth. Option D plays on the material scientist's instinct for precision, though stoichiometry is irrelevant to this phenomenon.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 990, "question": "Please briefly describe the basic conditions for the crystallization of binary alloys.", "answer": "Thermodynamic condition: $\\\\Delta G<0$; structural condition: $r>r^{*}$; energy condition: $A>\\\\Delta G_{\\\\mathrm{max}}$; composition condition.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述二元合金结晶的基本条件，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查二元合金结晶的基本条件，属于基本原理的记忆和理解，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目要求考生描述二元合金结晶的基本条件，涉及多个概念（热力学条件、结构条件、能量条件和成分条件）的解释和描述。虽然需要记忆多个知识点，但不需要进行复杂的比较分析或深入的概念体系阐述，属于中等难度的概念解释和描述题目。", "convertible": true, "correct_option": "Thermodynamic condition: $\\Delta G<0$; structural condition: $r>r^{*}$; energy condition: $A>\\Delta G_{\\mathrm{max}}$; composition condition.", "choice_question": "Which of the following describes the basic conditions for the crystallization of binary alloys?", "conversion_reason": "The answer is a standard set of conditions that can be presented as a correct option among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermodynamic condition: ΔG<0; structural condition: r>r*; energy condition: A>ΔG_max; composition condition", "B": "Thermodynamic condition: ΔG>0; structural condition: rr*; energy condition: A>ΔG_max; composition condition", "D": "Thermodynamic condition: ΔG<0; structural condition: r/2 type.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释NaCl型晶体结构中常见的位错Burgers向量类型，答案提供了文字解释而非计算或选择。 | 知识层次: 题目需要理解NaCl型晶体结构的基本特征，并应用Burgers矢量的相关知识进行判断。虽然不涉及复杂的计算，但需要对晶体结构和位错理论有一定的理解和关联分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握NaCl型晶体结构的基本知识，并能够将密度与Burgers矢量的概念关联起来。虽然题目给出了密度值，但正确选项直接指向了Burgers矢量的类型，减少了计算步骤的复杂性。因此，在选择题型中，这属于需要中等应用能力的题目，涉及概念关联和综合分析，但不需要进行复杂的多步计算或深度关联性分析。", "convertible": true, "correct_option": "In NaCl-type structures, the common dislocation Burgers vector is of the <110>/2 type.", "choice_question": "The density of a crystal with NaCl-type structure is 3.55g/cm³, what should its Burgers vector be?", "conversion_reason": "The answer is a standard terminology or concept related to the NaCl-type structure, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "<110>/2", "B": "<100>/2", "C": "<111>/3", "D": "<110>" }, "correct_answer": "A", "explanation": "In NaCl-type structures, the Burgers vector is typically <110>/2 due to the slip system in face-centered cubic crystals. Option B (<100>/2) exploits the common misconception about cubic symmetry directions. Option C (<111>/3) mimics the Burgers vector in BCC structures, creating a crystal system confusion trap. Option D (<110>) omits the critical /2 factor, targeting those who recall the direction but forget the magnitude.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2626, "question": "Given that the relative atomic mass of Si is 28.09, if there are 5×10^10 electrons capable of free movement in 100g of Si, calculate the proportion of freely moving electrons to the total number of valence electrons.", "answer": "Number of atoms = (100 / 28.09) × 6.023 × 10^23 = 2.144 × 10^24; Number of valence electrons = 4 × number of atoms = 4 × 2.144 × 10^24 = 8.576 × 10^24; Proportion = (5 × 10^10) / (8.576 × 10^24) = 5.830 × 10^-15", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，包括计算原子数量、价电子数量以及自由电子比例。答案以数值形式呈现，展示了具体的计算步骤和结果。 | 知识层次: 题目需要进行多步计算，包括原子数量的计算、价电子总数的计算以及最终比例的计算。虽然涉及的概念（相对原子质量、价电子）是基础的，但需要将这些概念关联起来进行综合分析。思维过程要求一定的深度，但不需要复杂的推理或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解相对原子质量、摩尔计算、价电子概念，并进行多步骤计算和综合分析。虽然题目提供了具体数值和计算步骤，但涉及的知识点较多且需要准确串联，对学生的概念掌握和计算能力要求较高。", "convertible": true, "correct_option": "5.830 × 10^-15", "choice_question": "Given that the relative atomic mass of Si is 28.09, if there are 5×10^10 electrons capable of free movement in 100g of Si, what is the proportion of freely moving electrons to the total number of valence electrons?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as the correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.830 × 10^-15", "B": "1.166 × 10^-14", "C": "2.915 × 10^-15", "D": "1.024 × 10^-13" }, "correct_answer": "A", "explanation": "The correct answer is calculated by first determining the total number of Si atoms in 100g (100/28.09 × Avogadro's number), then multiplying by 4 valence electrons per atom to get total valence electrons. The proportion is free electrons (5×10^10) divided by total valence electrons. Option B doubles the correct value, exploiting a common calculation error. Option C is half the correct value, targeting those who miscount valence electrons. Option D introduces an order-of-magnitude error by incorrectly handling Avogadro's number.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 829, "question": "Given that the recrystallization activation energy of a Cu-30%Zn alloy is 250 kJ/mol, and it takes 1 hour for this alloy to complete recrystallization at a constant temperature of 400°C, calculate how many hours it will take for this alloy to complete recrystallization at a constant temperature of 390°C.", "answer": "According to the formula, t2/t1 = exp[-Q/R(1/T1 - 1/T2)] = exp[-250×10^3/8.314×(1/(400+273) - 1/(390+273))] = 1.962. Therefore, t2 = t1×1.962 = 1.962 h.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来解决问题，答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及激活能和温度对再结晶时间的影响，需要应用Arrhenius方程进行数值计算，并理解温度与时间的关系。虽然计算过程较为直接，但需要将多个概念关联起来进行综合分析。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及激活能、温度与时间的关系，以及阿伦尼乌斯公式的应用。解题步骤包括温度单位的转换（摄氏温度到开尔文温度）、公式的正确代入和计算，以及对数运算。虽然题目提供了正确选项，但理解和应用这些概念需要一定的综合分析能力。", "convertible": true, "correct_option": "1.962 h", "choice_question": "Given that the recrystallization activation energy of a Cu-30%Zn alloy is 250 kJ/mol, and it takes 1 hour for this alloy to complete recrystallization at a constant temperature of 400°C, how many hours will it take for this alloy to complete recrystallization at a constant temperature of 390°C?", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.962 h", "B": "0.510 h", "C": "2.450 h", "D": "1.000 h" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Arrhenius equation for recrystallization kinetics. Option B (0.510 h) is designed to trap those who incorrectly invert the temperature ratio. Option C (2.450 h) exploits the common mistake of linear extrapolation from 400°C to 390°C. Option D (1.000 h) is a cognitive trap for those who assume negligible temperature effect over this small range. The correct calculation requires careful unit conversion (kJ to J, °C to K) and proper logarithmic treatment of the Arrhenius relationship.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3200, "question": "Does the ingot structure necessarily have three crystal zones?", "answer": "It should be pointed out that not all ingot structures have three crystal zones. Due to different solidification conditions, an ingot may only have one type of crystal zone or only two types of crystal zones.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断陈述的对错，即“铸锭结构是否必然有三个晶区”，而答案明确指出了该陈述的错误性，并解释了原因。这符合判断题的特征。 | 知识层次: 题目考查对铸锭结构基本概念的记忆和理解，涉及铸锭晶体区的分类和形成条件，属于基础概念层次。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度等级。题目考察的是对铸锭结构晶体区基本概念的理解，需要判断\"是否所有铸锭结构都必然具有三个晶体区\"这一陈述的正确性。虽然涉及基础概念记忆，但需要考生理解铸锭结构形成原理和不同凝固条件的影响，属于对概念理解的简单应用判断，比单纯记忆性知识（等级1）略高，但尚未达到需要分析复杂概念陈述的等级3难度。", "convertible": true, "correct_option": "It should be pointed out that not all ingot structures have three crystal zones. Due to different solidification conditions, an ingot may only have one type of crystal zone or only two types of crystal zones.", "choice_question": "Does the ingot structure necessarily have three crystal zones?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All metallic ingots solidify with three distinct crystal zones under industrial casting conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many metallic ingots exhibit three crystal zones (chill zone, columnar zone, and equiaxed zone), this is not universally true for all materials and solidification conditions. Factors like cooling rate, alloy composition, and nucleation conditions can result in fewer zones. The absolute term 'all' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3450, "question": "5CrNiMo, 3Cr2W8V, and H11 (or H13) all belong to hot-work die steels. Are there any differences in their usage? Why?", "answer": "Yes, there are differences. Their total alloying element contents are low-alloy (5CrNiMo), medium-alloy (H11), and high-alloy (3Cr2W8V), respectively. 5CrNiMo is used for hot forging dies, H11 replaces 3Cr2W8V for small and medium-sized mechanical forging dies and hot extrusion dies with relatively low operating temperatures, while 3Cr2W8V is used for hot extrusion dies. The reason for their differences in usage lies in the varying types and amounts of alloying elements, which result in different levels of thermal strength, thermal fatigue resistance, and high-temperature oxidation resistance, hence their different applications.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释不同热作模具钢的使用差异及其原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求对不同热作模具钢的使用差异进行比较和解释，涉及合金元素含量、热强度、热疲劳抗力等概念的综合分析，需要理解不同合金元素对性能的影响及其在实际应用中的选择依据。这属于中等应用层次，需要多步概念关联和综合分析。 | 难度: 在选择题型内，该题目属于较高难度，因为需要考生不仅掌握不同热作模具钢的基本分类（低合金、中合金、高合金），还要理解合金元素含量与性能（热强度、抗热疲劳性、高温抗氧化性）的关联性，并能综合分析不同钢种在实际应用中的选择依据（如锻造模、挤压模的工况差异）。题目要求将材料成分、性能、应用场景三个维度进行多角度关联分析，超越了单纯记忆或单一概念比较的层次。", "convertible": true, "correct_option": "Yes, there are differences. Their total alloying element contents are low-alloy (5CrNiMo), medium-alloy (H11), and high-alloy (3Cr2W8V), respectively. 5CrNiMo is used for hot forging dies, H11 replaces 3Cr2W8V for small and medium-sized mechanical forging dies and hot extrusion dies with relatively low operating temperatures, while 3Cr2W8V is used for hot extrusion dies. The reason for their differences in usage lies in the varying types and amounts of alloying elements, which result in different levels of thermal strength, thermal fatigue resistance, and high-temperature oxidation resistance, hence their different applications.", "choice_question": "5CrNiMo, 3Cr2W8V, and H11 (or H13) all belong to hot-work die steels. Are there any differences in their usage? Why?", "conversion_reason": "The answer is a detailed explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The differences are primarily due to their varying thermal conductivity values, with 3Cr2W8V having the highest conductivity for rapid heat dissipation in extrusion dies", "B": "5CrNiMo is used for hot forging dies due to its superior toughness, while H11 replaces 3Cr2W8V in lower temperature applications because of its better thermal fatigue resistance from higher vanadium content", "C": "The main difference lies in their hardness at room temperature, with 3Cr2W8V being hardest for wear resistance in extrusion dies, while 5CrNiMo is softer for better impact resistance in forging", "D": "Usage differences stem from their phase transformation temperatures, with H11 having the highest Ac1 temperature making it suitable for high-temperature operations" }, "correct_answer": "B", "explanation": "Correct answer B identifies the key factors: toughness for forging dies (5CrNiMo) and thermal fatigue resistance from vanadium (H11). Option A incorrectly focuses on thermal conductivity which is not the primary differentiator. Option C wrongly emphasizes room temperature hardness rather than high-temperature properties. Option D's phase transformation argument is misleading as Ac1 isn't the critical usage determinant.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1891, "question": "5. According to the thermodynamic theory of diffusion, the condition for reverse diffusion to occur is", "answer": "<0 or the thermodynamic factor of the diffusion coefficient is less than 0", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释热力学扩散理论中反向扩散发生的条件，需要文字论述和解释，而不是选择、判断或计算。 | 知识层次: 题目涉及热力学扩散理论中的反向扩散条件，需要理解扩散系数的热力学因子概念，并能够分析其与扩散方向的关系。这属于中等应用层次，需要将理论知识与具体条件相结合进行分析，而不仅仅是简单的记忆或直接套用公式。 | 难度: 在选择题中属于中等难度，需要理解扩散的热力学理论中的关键概念（如反向扩散的条件和扩散系数的热力学因子），并能将这些概念关联起来进行综合分析。题目要求考生不仅知道基本定义，还要能够应用这些知识来判断特定条件下的扩散行为。", "convertible": true, "correct_option": "the thermodynamic factor of the diffusion coefficient is less than 0", "choice_question": "According to the thermodynamic theory of diffusion, the condition for reverse diffusion to occur is:", "conversion_reason": "The answer is a standard concept in thermodynamics, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "the thermodynamic factor of the diffusion coefficient is less than 0", "B": "the concentration gradient exceeds the critical value for uphill diffusion", "C": "the chemical potential gradient is positive while the concentration gradient is negative", "D": "the activation energy for diffusion becomes temperature-dependent" }, "correct_answer": "A", "explanation": "The correct answer is A because reverse diffusion occurs when the thermodynamic factor (1 + dlnγ/dlnc) becomes negative, indicating non-ideal interactions. Option B is a cognitive bias trap - while concentration gradients are important, they alone cannot cause reverse diffusion. Option C exploits intuition by mixing correct concepts (chemical potential) with misleading phrasing. Option D targets confusion between diffusion mechanisms and thermodynamic driving forces.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4502, "question": "The permeability coefficient of a type of small gas molecule in a polymer is dependent on absolute temperature according to the following equation:\n\\[\nP_{M}=P_{M_{0}} \\exp \\left(-\\frac{Q_{p}}{R T}\\right)\n\\]\nwhere P_{M_{0}} and Q_{p} are constants for a given gas-polymer pair. Consider the diffusion of hydrogen through a poly(dimethyl siloxane) (PDMSO) sheet 20mm thick. The hydrogen pressures at the two faces are 10 kPa and 1 kPa, which are maintained constant. Compute the diffusion flux [in \\left({cm}^{3} STP\\right) / {cm}^{2}-s ] at 350 K. For this diffusion system\n\\[\n\\begin{array}{l}\nP_{M_{0}}=1.45 × 10^{-8}\\left(cm^{3} STP\\right)\\left({cm}^{3} / {cm}^{2}-s-\\mathrm{Pa}\\right. \\\\\nQ_{p}=13.7kJ / mol\n\\end{array}\n\\]\nAlso, assume a condition of steady state diffusion", "answer": "the diffusion flux is 5.90 × 10^{-7} \\frac{\\text{cm}^{3} \\text{stp}}{\\text{cm}^{2}·\\text{s}}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出一个具体的数值结果（扩散通量）。解答过程涉及公式应用和单位转换，符合计算题的特征。 | 知识层次: 题目需要应用给定的公式进行多步计算，包括温度对渗透系数的影响以及扩散通量的计算。虽然不涉及复杂的综合分析或推理，但需要理解公式中各参数的含义并进行正确的数值计算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及多步计算，包括理解渗透系数方程、应用稳态扩散条件、计算扩散通量等步骤。虽然题目提供了所有必要的参数和公式，但需要考生能够正确地将这些信息整合并应用到具体情境中。此外，题目还要求考生对单位转换和科学记数法有一定的掌握。因此，在选择题型内，这道题目属于综合性计算问题，难度等级为3。", "convertible": true, "correct_option": "5.90 × 10^{-7} \\frac{\\text{cm}^{3} \\text{stp}}{\\text{cm}^{2}·\\text{s}}", "choice_question": "The permeability coefficient of a type of small gas molecule in a polymer is dependent on absolute temperature according to the following equation:\n\\[\nP_{M}=P_{M_{0}} \\exp \\left(-\\frac{Q_{p}}{R T}\\right)\n\\]\nwhere P_{M_{0}} and Q_{p} are constants for a given gas-polymer pair. Consider the diffusion of hydrogen through a poly(dimethyl siloxane) (PDMSO) sheet 20mm thick. The hydrogen pressures at the two faces are 10 kPa and 1 kPa, which are maintained constant. Compute the diffusion flux [in \\left({cm}^{3} STP\\right) / {cm}^{2}-s ] at 350 K. For this diffusion system\n\\[\n\\begin{array}{l}\nP_{M_{0}}=1.45 × 10^{-8}\\left(cm^{3} STP\\right)\\left({cm}^{3} / {cm}^{2}-s-\\mathrm{Pa}\\right. \\\\\nQ_{p}=13.7kJ / mol\n\\end{array}\n\\]\nAlso, assume a condition of steady state diffusion. The diffusion flux is:", "conversion_reason": "The calculation problem has a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.90 × 10^{-7} \frac{\text{cm}^{3} \text{STP}}{\text{cm}^{2}·\text{s}}", "B": "1.18 × 10^{-6} \frac{\text{cm}^{3} \text{STP}}{\text{cm}^{2}·\text{s}}", "C": "2.95 × 10^{-7} \frac{\text{cm}^{3} \text{STP}}{\text{cm}^{2}·\text{s}}", "D": "3.54 × 10^{-6} \frac{\text{cm}^{3} \text{STP}}{\text{cm}^{2}·\text{s}}" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the given permeability equation and steady-state diffusion conditions. Option B doubles the correct value, exploiting the common error of not converting mm to cm in thickness. Option C is half the correct value, targeting those who might confuse pressure difference (9 kPa) with individual pressures. Option D introduces an order-of-magnitude error by using kJ instead of J in the exponential term calculation, a subtle unit conversion trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 213, "question": "Many properties of clay are related to the types of adsorbed cations. Indicate the variation pattern of the filtrate loss of clay slurry adsorbed with the following different cations (use arrows to represent: small—large) H+ Al3+ Ba2+ Sr2+ Ca2+ Mg2+ NH4+ K+ Na+ Li+", "answer": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来回答，具体表现为使用箭头符号表示不同阳离子对粘土浆滤失量的影响顺序，属于需要描述和排列的简答题类型。 | 知识层次: 题目要求考生理解不同阳离子对粘土滤失量的影响，并能够根据离子特性（如电荷、半径等）进行排序。这需要将多个概念（离子吸附、离子半径、电荷效应等）关联起来进行分析，属于中等应用层次。虽然不涉及复杂计算，但需要对离子特性及其对粘土性质的影响有较深入的理解。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生理解粘土吸附不同阳离子后滤失量的变化规律，并正确排列顺序。这需要考生掌握粘土吸附阳离子的基本原理（如离子价态、水化半径等对吸附性能的影响），并能将这些概念综合应用到具体例子中。此外，题目涉及的阳离子种类较多（10种），增加了比较和分析的复杂性。正确选项的排列顺序需要考生进行多步推理和概念关联，属于中等应用层次的知识要求。因此，在选择题型内属于等级4的难度。", "convertible": true, "correct_option": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "choice_question": "Which of the following correctly represents the variation pattern of the filtrate loss of clay slurry adsorbed with the given cations (from small to large)?", "conversion_reason": "The answer is a specific ordered sequence, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "B": "Al3+ < H+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "C": "H+ < Al3+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < NH4+ < K+ < Na+ < Li+", "D": "Al3+ < H+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < NH4+ < K+ < Na+ < Li+" }, "correct_answer": "A", "explanation": "The correct sequence is determined by the hydration energy and ionic potential of the cations. H+ has the smallest ionic radius and highest charge density, leading to the least filtrate loss. Al3+ follows due to its high charge. The divalent cations (Ba2+, Sr2+, Ca2+, Mg2+) are ordered by increasing hydration energy. Monovalent cations (NH4+, K+, Na+, Li+) follow with increasing hydration energy. Option B incorrectly places Al3+ before H+. Option C and D incorrectly order the divalent cations based on atomic number rather than hydration energy, a common mistake when relying on periodic trends alone.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3607, "question": "Determine the packing fraction for BCC lithium in the (110) plane.", "answer": "packing fraction = 0.833", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算BCC锂在(110)平面的堆积分数，需要应用晶体结构和几何关系的公式进行数值计算，最终给出一个具体的数值结果（0.833）。 | 知识层次: 题目需要计算BCC结构在特定晶面(110)的堆积分数，涉及晶体几何关系的理解和多步计算（包括原子半径与晶格常数的关系、晶面原子密度的计算等），属于需要概念关联和综合分析的中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构、(110)平面的原子排列，并进行多步几何计算来求解堆积分数。虽然题目给出了正确选项，但解题过程涉及晶体学概念的综合应用和计算步骤的衔接，属于需要综合分析能力的题目。", "convertible": true, "correct_option": "0.833", "choice_question": "What is the packing fraction for BCC lithium in the (110) plane?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.833", "B": "0.680", "C": "0.740", "D": "0.906" }, "correct_answer": "A", "explanation": "The correct answer is A (0.833) because in BCC lithium's (110) plane, there are 2 atoms contributing to the plane area with a packing fraction calculation yielding this value. Option B (0.680) exploits the cognitive bias of using FCC packing fraction. Option C (0.740) is a professional intuition trap using the bulk BCC packing fraction. Option D (0.906) is a multi-level verification trap that incorrectly applies HCP close-packing values to this scenario.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1617, "question": "The equilibrium concentration of point defects increases with the rise of __ (4).", "answer": "(4) temperature", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个单词（temperature）来补全句子，属于需要简短文字回答的类型，没有提供选项或要求判断对错，也不需要计算。 | 知识层次: 题目考查点缺陷平衡浓度与温度关系的基本概念记忆，属于材料科学基础理论中的基本原理记忆性知识。 | 难度: 在选择题型中，此题属于基础概念记忆题，仅需考生记住\"温度升高会增加点缺陷平衡浓度\"这一基本原理即可作答。题目直接考查定义性知识，不需要解释或分析过程，解题步骤极为简单，属于选择题中最基础的难度等级。", "convertible": true, "correct_option": "temperature", "choice_question": "The equilibrium concentration of point defects increases with the rise of:", "conversion_reason": "The answer is a standard term (temperature) and the question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "temperature", "B": "applied stress", "C": "grain size", "D": "cooling rate" }, "correct_answer": "A", "explanation": "The correct answer is A because point defect concentration follows Arrhenius-type temperature dependence according to thermodynamic principles. Option B exploits the common confusion between equilibrium defects and stress-induced defects. Option C targets the misconception that grain boundaries act as defect sources at equilibrium. Option D capitalizes on the intuitive but incorrect association between rapid cooling and defect retention, which is a kinetic rather than thermodynamic effect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3132, "question": "Explain the basic concept and terminology: superplasticity", "answer": "Superplasticity: Under specific conditions, metallic materials can achieve exceptionally large elongation rates when stretched, sometimes even reaching 1000%. This property is called superplasticity. During superplastic deformation, the strain rate sensitivity index m is very high, with m≈0.5, whereas for ordinary metallic materials it is only 0.01~0.04.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释超塑性的基本概念和术语，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对超塑性这一基本概念的定义和特性的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释超塑性的基本概念和术语，但正确选项已经提供了较为详细的定义和关键参数（如应变速率敏感性指数m的数值范围）。考生需要理解并记忆这些关键点，但不需要进行复杂的分析或比较。因此，该题目在选择题型内属于等级2，即概念解释和描述的难度水平。", "convertible": true, "correct_option": "Superplasticity: Under specific conditions, metallic materials can achieve exceptionally large elongation rates when stretched, sometimes even reaching 1000%. This property is called superplasticity. During superplastic deformation, the strain rate sensitivity index m is very high, with m≈0.5, whereas for ordinary metallic materials it is only 0.01~0.04.", "choice_question": "Which of the following best describes the concept of superplasticity?", "conversion_reason": "The answer is a standard definition of a technical term, which can be converted into a multiple-choice question format by presenting it as the correct option among several plausible but incorrect alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Superplasticity: Under specific conditions, metallic materials can achieve exceptionally large elongation rates when stretched, sometimes even reaching 1000%. This property is called superplasticity. During superplastic deformation, the strain rate sensitivity index m is very high, with m≈0.5, whereas for ordinary metallic materials it is only 0.01~0.04.", "B": "Superplasticity refers to the ability of ceramic materials to undergo significant plastic deformation at high temperatures (above 0.8Tm) without fracture, typically showing elongation rates of 200-300% due to grain boundary sliding controlled by diffusion processes.", "C": "Superplasticity describes the phenomenon where polymer composites exhibit extreme ductility (500-800% elongation) at room temperature through molecular chain alignment, with the strain rate sensitivity index m approaching 1.0 in this regime.", "D": "Superplasticity is observed in metallic alloys when deformed at cryogenic temperatures, resulting in elongation exceeding 500% due to suppression of dislocation motion and activation of alternative deformation mechanisms with m≈0.3." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines superplasticity in metallic materials with key characteristics: exceptional elongation (up to 1000%), specific conditions (typically elevated temperatures and controlled strain rates), and high strain rate sensitivity (m≈0.5). Option B incorrectly applies the concept to ceramics - while they can show limited plasticity at high temperatures, true superplasticity with such large elongations is characteristic of metals. Option C creates a polymer science confusion trap - while polymers can show large elongations, the mechanisms and m-values differ fundamentally from metallic superplasticity. Option D uses a cryogenic temperature red herring - superplasticity requires elevated temperatures to enable grain boundary sliding mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2760, "question": "In a body-centered cubic structure, can a dislocation with Burgers vector $a[100]$ decompose into $\\frac{a}{2}[111]+\\frac{a}{2}[1\\overline{1}\\overline{1}]$? (A) No (B) Yes (C) Possible", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求从给定的选项（A、B、C）中选择正确答案，符合选择题的特征。 | 知识层次: 题目涉及位错分解的矢量分析，需要理解Burgers矢量的几何关系、位错分解的能量条件以及晶体结构对位错行为的限制。这需要综合运用晶体学、位错理论和能量分析等多方面知识，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。它要求考生不仅掌握体心立方结构中的位错分解原理，还需要深入理解Burgers矢量的计算和能量守恒条件。解题步骤涉及复杂的矢量运算和能量分析，需要综合运用多个知识点进行推理判断。此外，题目中的选项设计也增加了判断的复杂性，要求考生具备深度推理和机理分析能力。", "convertible": true, "correct_option": "A", "choice_question": "In a body-centered cubic structure, can a dislocation with Burgers vector $a[100]$ decompose into $\\frac{a}{2}[111]+\\frac{a}{2}[1\\overline{1}\\overline{1}]$?", "conversion_reason": "The original question is already in a multiple-choice format with clear options and a single correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because the vector sum does not equal the original Burgers vector", "B": "Yes, as this decomposition reduces strain energy in BCC crystals", "C": "Possible, if the dislocation is under high shear stress conditions", "D": "Yes, because both partial dislocations have equal magnitude" }, "correct_answer": "A", "explanation": "The correct answer is A because the vector sum of the proposed decomposition (a[111]/2 + a[1-1-1]/2 = a[100]) mathematically matches the original Burgers vector, but this decomposition is physically impossible in BCC structures due to crystallographic constraints. Option B exploits the common misconception that energy reduction always enables decomposition. Option C creates a false scenario where stress conditions could enable impossible reactions. Option D appeals to the symmetry heuristic that equal magnitudes imply validity, which is misleading here.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4517, "question": "For the following pair of polymers, do the following: (1) state whether or not it is possible to determine whether one polymer has a higher melting temperature than the other; (2) if it is possible, note which has the higher melting temperature and then cite reason(s) for your choice; and (3) if it is not possible to decide, then state why. Branched and isotactic polystyrene that has a degree of polymerization of 4,000; linear and isotactic polypropylene that has a degree of polymerization of 7,500", "answer": "No, it is not possible to determine which of the two polymers has the higher melting temperature. The polystyrene has a bulkier side group than the polypropylene; on the basis of this effect alone, the polystyrene should have the greater Tm. However, the polystyrene has more branching and a lower degree of polymerization; both of these factors lead to a lowering of the melting temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求对两种聚合物的熔点进行比较，并详细解释原因或说明无法比较的理由。答案需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目要求比较两种聚合物的熔点，涉及分子结构（支化、等规性）、侧基体积效应和聚合度等多个因素的权衡分析。虽然不需要复杂的计算，但需要对聚合物结构与性能关系有较深入的理解，并能综合多个影响因素进行判断。这属于中等应用层次，需要概念关联和综合分析能力。 | 难度: 在选择题型中，该题目属于较高难度，因为它要求考生进行多角度分析论述。具体来说，考生需要：", "convertible": true, "correct_option": "No, it is not possible to determine which of the two polymers has the higher melting temperature.", "choice_question": "For the following pair of polymers, is it possible to determine whether one polymer has a higher melting temperature than the other? Branched and isotactic polystyrene that has a degree of polymerization of 4,000; linear and isotactic polypropylene that has a degree of polymerization of 7,500", "conversion_reason": "The answer is a clear statement that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by focusing on the possibility of determining the higher melting temperature.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because the branching in polystyrene offsets its higher inherent chain stiffness compared to polypropylene", "B": "Yes, linear and isotactic polypropylene will always have higher Tm due to its simpler chain structure", "C": "Yes, branched and isotactic polystyrene must have higher Tm because aromatic rings increase chain rigidity", "D": "No, because the degree of polymerization difference makes direct comparison impossible" }, "correct_answer": "A", "explanation": "The correct answer is A because: (1) Polystyrene's aromatic rings do increase chain stiffness (tempting for answer C), but branching significantly reduces crystallinity and Tm; (2) While polypropylene is linear (tempting for answer B), its lower inherent chain stiffness compared to polystyrene means the outcome isn't certain; (3) The degree of polymerization difference (tempting for answer D) is actually above the threshold where it significantly affects Tm for these polymers. The key is recognizing that branching effects and inherent stiffness are competing factors that can't be quantitatively compared without experimental data.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2332, "question": "According to solidification theory, how does vibration crystallization refine the grain size of castings?", "answer": "Vibration crystallization, on one hand, provides the energy required for nucleation, and on the other hand, can break the growing crystals to form more crystallization nuclei, thereby refining the grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释振动结晶如何细化铸件晶粒，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释振动结晶如何细化铸件晶粒的机理，涉及固体理论中的成核和晶体生长过程，需要综合运用多个概念进行推理分析，思维过程较为深入。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解振动结晶的基本概念，还需要综合运用凝固理论中的成核和晶体生长机理，分析振动能量对晶粒细化的双重作用机制（提供成核能量和破碎晶体）。这需要考生具备将复杂现象分解为多个相互作用因素的能力，并能够解释其内在物理机制，属于典型的复杂现象全面分析层次。在选择题型中，这种需要多步骤推理和机理深度解释的题目对考生的知识整合能力和分析能力要求极高。", "convertible": true, "correct_option": "Vibration crystallization, on one hand, provides the energy required for nucleation, and on the other hand, can break the growing crystals to form more crystallization nuclei, thereby refining the grains.", "choice_question": "According to solidification theory, how does vibration crystallization refine the grain size of castings?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Vibration increases nucleation sites by promoting heterogeneous nucleation at impurities", "B": "Mechanical vibration disrupts dendrite growth by introducing dislocations at grain boundaries", "C": "Acoustic waves from vibration reduce surface tension at the solid-liquid interface", "D": "Periodic stress fields from vibration prevent solute segregation during solidification" }, "correct_answer": "A", "explanation": "Correct answer A addresses the primary mechanism where vibration energy promotes nucleation at existing impurities. Option B incorrectly suggests dislocation formation affects dendrites during solidification. Option C falsely attributes grain refinement to surface tension modification. Option D describes a real but secondary effect unrelated to grain size reduction.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4252, "question": "The diffusion coefficients for silver in copper are given at two temperatures: T(°C) = 650, D(m2/s) = 5.5 × 10^-16 and T(°C) = 900, D(m2/s) = 1.3 × 10^-13. Determine the values of D0 and Qd.", "answer": "the values are d0 = 7.5 × 10^-5 m2/s and qd = 196,700 j/mol.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的扩散系数和温度数据，计算D0和Qd的值。解答过程需要应用阿伦尼乌斯方程进行数值计算，答案也是具体的数值结果。这符合计算题的特征。 | 知识层次: 题目需要应用阿伦尼乌斯方程进行多步计算，涉及温度转换、对数运算和线性回归分析，需要概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解阿伦尼乌斯方程的概念，并进行多步计算（包括对数运算和单位转换）。虽然题目提供了正确选项，但解题过程涉及温度转换、方程联立求解等综合分析步骤，对学生的计算能力和概念掌握深度有较高要求。", "convertible": true, "correct_option": "D0 = 7.5 × 10^-5 m2/s and Qd = 196,700 J/mol", "choice_question": "Given the diffusion coefficients for silver in copper at two temperatures: T(°C) = 650, D(m2/s) = 5.5 × 10^-16 and T(°C) = 900, D(m2/s) = 1.3 × 10^-13, determine the values of D0 and Qd.", "conversion_reason": "The answer is a specific set of values, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "D0 = 7.5 × 10^-5 m2/s and Qd = 196,700 J/mol", "B": "D0 = 2.1 × 10^-6 m2/s and Qd = 145,300 J/mol", "C": "D0 = 1.3 × 10^-13 m2/s and Qd = 89,500 J/mol", "D": "D0 = 5.5 × 10^-16 m2/s and Qd = 112,400 J/mol" }, "correct_answer": "A", "explanation": "The correct answer is derived from the Arrhenius equation for diffusion (D = D0 exp(-Qd/RT)) by solving the simultaneous equations for the two given temperatures. Option B uses values typical for interstitial diffusion rather than substitutional diffusion (Ag in Cu). Option C incorrectly uses one of the given D values as D0, a common conceptual error. Option D makes the opposite mistake of using the other D value as D0, while also underestimating the activation energy due to incorrect temperature conversion assumptions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4587, "question": "At temperatures between 775^{\\circ} C\\left(1048 K\\right) and 1100^{\\circ} C\\left(1373 K\\right), the activation energy and preexponential for the diffusion coefficient of \\mathrm{Fe}^{2+} in \\mathrm{FeO} are 102,000 J/ mol and 7.3 × 10^{-8}{m}^{2} / s, respectively. Compute the mobility for an \\mathrm{Fe}^{2+} ion at 1000^{\\circ} C(1273 K).", "answer": "the mobility for an \\mathrm{fe}^{2+} ion at 1000^{\\circ} C (1273 k) is 8.64 × 10^{-11}{m}^{2} / \\mathrm{v}·s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的激活能和前置指数计算Fe2+离子在特定温度下的迁移率，需要使用公式进行数值计算。答案也是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括应用扩散系数公式和计算离子迁移率，涉及概念关联和综合分析，但不需要复杂的推理分析或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散系数与迁移率的关系，并应用阿伦尼乌斯公式进行多步计算。题目涉及温度转换、激活能应用和单位换算，虽然计算步骤明确但需要较强的概念关联能力。", "convertible": true, "correct_option": "8.64 × 10^{-11} m²/V·s", "choice_question": "At temperatures between 775°C (1048 K) and 1100°C (1373 K), the activation energy and preexponential for the diffusion coefficient of Fe²⁺ in FeO are 102,000 J/mol and 7.3 × 10⁻⁸ m²/s, respectively. What is the mobility for an Fe²⁺ ion at 1000°C (1273 K)?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.64 × 10^{-11} m²/V·s", "B": "4.32 × 10^{-11} m²/V·s", "C": "1.73 × 10^{-10} m²/V·s", "D": "3.46 × 10^{-10} m²/V·s" }, "correct_answer": "A", "explanation": "正确答案A是通过正确的Nernst-Einstein关系计算得出：μ = Dq/kT，其中q=2e。干扰项B设计为正确答案的一半，利用AI可能忽略电荷数2的陷阱；干扰项C是正确答案的两倍，利用可能错误计算温度倒数或电荷数的直觉错误；干扰项D是正确答案的四倍，针对可能同时犯电荷数和温度计算双重错误的AI模型。所有干扰项都保持合理的数量级范围，增加判断难度。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2347, "question": "Pure iron transforms from bcc structure to fcc structure at 17°C, with a volume reduction of 1.06%. Calculate the relative change in atomic radius.", "answer": "The relative change in atomic radius is (r_f - r_b)/r_b = 1 - 1/0.9758 = -2.47%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解原子半径的相对变化，答案给出了具体的计算过程和结果。 | 知识层次: 题目需要理解bcc和fcc晶体结构的特点，应用体积变化与原子半径的关系进行多步计算，涉及概念关联和综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构转变的概念，掌握体积变化与原子半径的关系，并进行多步计算。虽然题目提供了体积变化数据，但需要考生自行推导原子半径变化的计算公式，并正确执行计算步骤。这比单纯记忆概念或执行单步计算的选择题更为复杂，但尚未达到需要处理多变量或极端复杂计算的最高难度水平。", "convertible": true, "correct_option": "-2.47%", "choice_question": "Pure iron transforms from bcc structure to fcc structure at 17°C, with a volume reduction of 1.06%. What is the relative change in atomic radius?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format where one of the options would be the correct percentage change.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-2.47%", "B": "-1.06%", "C": "-0.53%", "D": "-3.18%" }, "correct_answer": "A", "explanation": "正确答案A(-2.47%)是通过精确计算bcc和fcc结构的原子堆积因子变化得出的。干扰项B(-1.06%)直接使用了体积变化率，利用了'第一印象'认知偏差。干扰项C(-0.53%)是体积变化率的一半，利用了简单线性关系的直觉陷阱。干扰项D(-3.18%)是通过错误假设体积变化与半径变化呈立方关系计算得出的，属于专业直觉陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2713, "question": "For a cubic crystal with side length L, derive the volume change rate ΔV0/V0 due to thermal expansion when the temperature increases from T1 to T2.", "answer": "ΔV0/V0 = (L + ΔL)^3 - L^3 / L^3 = 3 × (ΔL/L).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过公式推导和数值计算来求解体积变化率，答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目要求应用基本的体积变化公式和热膨胀概念进行简单计算，涉及直接套用公式和一步推导，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要理解热膨胀的基本概念和立方体体积公式，但解题步骤仅涉及直接套用体积变化率公式（ΔV0/V0 = 3 × (ΔL/L)），无需多步推导或复杂计算。相比单一公式直接计算的等级1题目，该题需要稍高的理解能力，但仍属于选择题中的基础难度范畴。", "convertible": true, "correct_option": "3 × (ΔL/L)", "choice_question": "For a cubic crystal with side length L, what is the volume change rate ΔV0/V0 due to thermal expansion when the temperature increases from T1 to T2?", "conversion_reason": "The answer is a specific mathematical expression, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3 × (ΔL/L)", "B": "(ΔL/L)^3", "C": "3 × α × (T2-T1)", "D": "α × (T2-T1)^3" }, "correct_answer": "A", "explanation": "The correct answer is A because for a cubic crystal, the volume change rate is simply three times the linear expansion rate (ΔL/L) due to isotropic expansion in all three dimensions. Option B is a cognitive bias trap that incorrectly assumes volume change should be the cube of linear change. Option C uses the correct coefficient (3) but incorrectly substitutes thermal expansion coefficient α directly without relating to ΔL/L. Option D is a multi-layer trap combining the wrong exponent with the thermal expansion coefficient.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1975, "question": "In the <100> direction of iron (bcc, a=0.286nm), what is the linear density of atoms?", "answer": "The linear density of Fe atoms is 3.50×10^6 atoms/mm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算铁在<100>方向上的线性原子密度，需要应用晶体结构和晶格常数的知识进行数值计算，答案是一个具体的数值结果。 | 知识层次: 题目需要应用基本的线性密度计算公式，并代入已知的晶格常数进行简单计算，属于直接套用公式的简单应用层次。 | 难度: 在选择题型内，该题目属于单一公式直接计算的难度等级。题目要求计算铁在<100>方向的线性原子密度，仅需应用基本的线性密度公式（1/a）并进行单位转换即可得出答案。无需复杂的推导或多步骤计算，属于最基础的应用题类型。", "convertible": true, "correct_option": "3.50×10^6 atoms/mm", "choice_question": "In the <100> direction of iron (bcc, a=0.286nm), what is the linear density of atoms?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.50×10^6 atoms/mm", "B": "1.75×10^6 atoms/mm", "C": "7.00×10^6 atoms/mm", "D": "4.95×10^6 atoms/mm" }, "correct_answer": "A", "explanation": "The linear density in the <100> direction of bcc iron is calculated by considering the distance between atoms along this direction. In bcc, the <100> direction has atoms spaced by the lattice parameter 'a' (0.286nm). The linear density is 1/a = 3.50×10^6 atoms/mm. Option B is half the correct value, tempting those who incorrectly divide by 2 due to bcc's body-centered nature. Option C doubles the correct value, targeting those who confuse <100> with <110> direction spacing. Option D uses √2/a, a common mistake from incorrectly applying face-centered cubic calculations to bcc.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 550, "question": "1. Crystals can be classified into (1) crystal families, (2) crystal systems according to symmetry, with a total of (3) point groups and (4) space groups.", "answer": "(1) 3; (2) 7; (3) 32; (4) 230", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的数值答案，而不是从给定的选项中选择。虽然答案简短，但需要基于对晶体分类系统的理解来回答，属于简答题的范畴。 | 知识层次: 题目考查晶体分类、对称性和点群/空间群数量的基础概念记忆，属于材料科学中最基本的晶体学知识，不需要复杂的应用或分析过程。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需回忆晶体学中的基本分类数字（3个晶族、7个晶系、32个点群、230个空间群）。题目不涉及概念解释或复杂体系分析，仅测试对关键数字的记忆准确性，因此属于最低难度等级。", "convertible": true, "correct_option": "(1) 3; (2) 7; (3) 32; (4) 230", "choice_question": "Crystals can be classified into (1) crystal families, (2) crystal systems according to symmetry, with a total of (3) point groups and (4) space groups. The correct numbers are:", "conversion_reason": "The answer is a set of standard numerical values, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(1) 3; (2) 7; (3) 32; (4) 230", "B": "(1) 7; (2) 14; (3) 32; (4) 230", "C": "(1) 3; (2) 7; (3) 14; (4) 230", "D": "(1) 7; (2) 7; (3) 32; (4) 230" }, "correct_answer": "A", "explanation": "正确答案A完全符合晶体学分类标准：3个晶族（三斜、单斜、正交/四方/立方/三方/六方）、7个晶系、32个点群和230个空间群。干扰项B利用晶系与布拉维格子数量(14)的混淆；C通过点群与晶系数量(7)的数值接近性制造陷阱；D则利用晶族与晶系数量相同的表面合理性。这些干扰项都针对AI可能存在的对称性分类记忆模糊问题。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 719, "question": "The dislocation line of an edge dislocation is parallel to the slip direction.", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（用×表示错误），符合判断题的特征 | 知识层次: 题目考查对位错线方向与滑移方向关系的基本概念记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念正误判断，仅需记忆边缘位错的位错线与滑移方向的关系即可作答，无需深入理解或分析。", "convertible": true, "correct_option": "×", "choice_question": "The dislocation line of an edge dislocation is parallel to the slip direction.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect ionic bonding with no covalent character.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics have predominantly ionic bonding, most exhibit some degree of covalent character. The statement uses an absolute term 'all' which is incorrect. Even classic ionic ceramics like NaCl have about 5% covalent character due to electron sharing. Advanced ceramics like silicon carbide (SiC) are predominantly covalently bonded.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1930, "question": "What is the difference between intrinsic diffusion and extrinsic diffusion?", "answer": "The activation energy of intrinsic diffusion consists of both vacancy formation energy and particle migration energy, while the activation energy of extrinsic diffusion only includes particle migration energy; intrinsic diffusion dominates at high temperatures, whereas extrinsic diffusion dominates at low temperatures.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释内在扩散和外在扩散的区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对扩散类型的基本概念记忆和理解，包括内在扩散和外在扩散的定义及其激活能量的组成差异，以及温度对扩散类型的影响。这些都属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及两个概念（本征扩散和外征扩散）的比较，但正确选项已经明确列出了两者的关键区别（激活能组成和温度依赖性）。这要求考生不仅要记忆两个扩散机制的定义，还需要理解它们之间的对比关系。不过由于选择题型提供了明确的选项提示，相比开放式简答降低了难度，因此属于等级2（概念解释和描述）而非更复杂的等级3。", "convertible": true, "correct_option": "The activation energy of intrinsic diffusion consists of both vacancy formation energy and particle migration energy, while the activation energy of extrinsic diffusion only includes particle migration energy; intrinsic diffusion dominates at high temperatures, whereas extrinsic diffusion dominates at low temperatures.", "choice_question": "What is the difference between intrinsic diffusion and extrinsic diffusion?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be converted by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Intrinsic diffusion involves both vacancy formation and atomic migration, while extrinsic diffusion is driven solely by pre-existing defects", "B": "Intrinsic diffusion occurs in pure materials, while extrinsic diffusion requires impurity atoms as diffusion mediators", "C": "Intrinsic diffusion follows Fick's first law, while extrinsic diffusion requires Fick's second law for description", "D": "Intrinsic diffusion has a constant activation energy, while extrinsic diffusion shows temperature-dependent activation energy" }, "correct_answer": "A", "explanation": "Correct answer A precisely captures the fundamental difference in activation energy components and defect involvement. Option B is a cognitive bias trap, incorrectly suggesting impurity mediation which actually describes impurity diffusion, not extrinsic diffusion. Option C exploits law-selection confusion, while both diffusion types can be described by Fick's laws. Option D reverses the actual temperature dependence characteristics, creating a professional intuition trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4162, "question": "A beam of light is shined on a thin (sub-millimeter thick) single crystal wafer of material. The light source is special since it can be tuned to provide any wavelength of visible light on demand. The specimen is illuminated such that the frequency of light is decreased over time while the transmitted intensity of the light is measured. If the sample becomes transparent when the frequency is less than [F] THz, what is the band gap of the material, in eV? Assume that an intrinsic excitation of electrons is responsible for the absorption.", "answer": "the band gap of the material is 4.135 × 10^{-3} [f] ev.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（将频率转换为电子伏特）来确定材料的带隙，答案是一个具体的数值计算结果。 | 知识层次: 题目主要涉及基本公式应用和简单计算，即通过给定的频率计算材料的带隙能量。虽然需要理解带隙与光频率之间的关系，但整体思维过程较为直接，属于简单应用层次。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求根据给定的频率计算材料的带隙，只需应用基本公式E = hν（其中h是普朗克常数，ν是频率）进行简单转换即可得到正确答案。解题步骤非常直接，无需复杂的推导或多步骤计算，符合等级1的标准。", "convertible": true, "correct_option": "4.135 × 10^{-3} [f] ev", "choice_question": "A beam of light is shined on a thin (sub-millimeter thick) single crystal wafer of material. The light source is special since it can be tuned to provide any wavelength of visible light on demand. The specimen is illuminated such that the frequency of light is decreased over time while the transmitted intensity of the light is measured. If the sample becomes transparent when the frequency is less than [F] THz, what is the band gap of the material, in eV? Assume that an intrinsic excitation of electrons is responsible for the absorption.", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.135 × 10^{-3} [F] eV", "B": "1.239 × 10^{-3} [F] eV", "C": "6.582 × 10^{-3} [F] eV", "D": "2.998 × 10^{-3} [F] eV" }, "correct_answer": "A", "explanation": "The correct answer A uses Planck's constant (h = 4.135 × 10^{-15} eV·s) to convert frequency to energy (E = hν). Option B incorrectly uses hc (combining Planck's constant with speed of light), which is relevant for wavelength calculations but not pure frequency. Option C uses the reduced Planck constant (ħ = 6.582 × 10^{-16} eV·s), a common mistake when dealing with angular frequency. Option D incorporates the speed of light (c = 2.998 × 10^8 m/s) unnecessarily, creating a dimensionally incorrect result.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3224, "question": "A copper single crystal is subjected to tension with the tensile axis along the [001] direction and σ=10^6 Pa. Calculate the force acting on a screw dislocation line with Burgers vector b=(a/2)[1̄01] on the (111) plane. Given a_Cu=0.36 nm.", "answer": "The tensile stress is applied along the [001] direction. On the (111) slip plane, the resolved shear stress along the [1̄01] direction is τ=σcosφcosλ, where cosφ=1/√3, cosλ=1/√2, and σ=10^6 Pa. Thus, τ=10^6×(1/√3)×(1/√2)≈4.08×10^5 Pa. The force per unit length on the dislocation line is F_d=τb=4.08×10^5×(√2/2)×0.36×10^(-9)≈1.04×10^(-4) N/m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及应力分解、剪切应力计算以及位错线受力计算等具体运算步骤，最终需要得出具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括计算分解剪切应力、应用施密特定律、计算位错受力等步骤。虽然涉及的概念和公式较为基础，但需要将这些概念和公式关联起来进行综合分析，思维过程有一定的深度要求。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如Burgers向量、滑移面、分解剪应力等）并进行多步计算（包括方向余弦计算、分解剪应力公式应用、单位转换等）。虽然题目提供了具体公式和步骤，但综合应用和计算过程仍具有一定复杂性，属于综合性计算问题。", "convertible": true, "correct_option": "1.04×10^(-4) N/m", "choice_question": "A copper single crystal is subjected to tension with the tensile axis along the [001] direction and σ=10^6 Pa. The force acting on a screw dislocation line with Burgers vector b=(a/2)[1̄01] on the (111) plane is: (Given a_Cu=0.36 nm)", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.04×10^(-4) N/m", "B": "2.08×10^(-4) N/m", "C": "5.20×10^(-5) N/m", "D": "7.35×10^(-5) N/m" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算Peach-Koehler力公式得到的。干扰项B通过错误地加倍计算结果来利用认知偏差；干扰项C通过使用错误的剪切模量计算来制造专业直觉陷阱；干扰项D通过错误地使用(110)平面而非(111)平面的计算来设置多层次验证陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4274, "question": "For mixed dislocation, cite the relationship between the direction of the applied shear stress and the direction of dislocation line motion.", "answer": "mixed dislocation--neither parallel nor perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释混合位错中施加剪切应力方向与位错线运动方向之间的关系，答案需要论述而非选择或判断 | 知识层次: 题目考查对混合位错基本概念的记忆和理解，特别是位错线运动方向与外加剪切应力方向的关系这一基本原理。 | 难度: 在选择题型中，该题目仅要求记忆混合位错的基本定义和分类，即混合位错的方向与外加剪切应力方向的关系。题目直接给出了正确选项，不需要复杂的推理或概念间的比较分析，属于最基础的概念记忆题。", "convertible": true, "correct_option": "mixed dislocation--neither parallel nor perpendicular", "choice_question": "For mixed dislocation, what is the relationship between the direction of the applied shear stress and the direction of dislocation line motion?", "conversion_reason": "The answer is a standard terminology that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The motion direction is always parallel to the Burgers vector", "B": "The motion direction is determined by the screw component of the dislocation", "C": "The motion direction is neither parallel nor perpendicular to the applied stress", "D": "The motion direction follows the maximum resolved shear stress direction" }, "correct_answer": "C", "explanation": "For mixed dislocations, the motion direction is neither parallel nor perpendicular to the applied stress due to the combined edge and screw components. Option A exploits the common confusion with pure edge dislocations. Option B targets the misconception that screw components dominate the motion. Option D is a cognitive trap using the correct principle but applying it incorrectly to mixed dislocations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3512, "question": "Compare the machinability of HT150 and annealed 20 steel", "answer": "The machinability of HT150 is better than that of 20 steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的机械加工性能，答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求比较两种材料的可加工性，需要理解材料性能（如硬度、强度等）与可加工性的关系，并进行综合分析。这涉及多个概念的关联和应用，但不需要复杂的机理分析或创新设计。 | 难度: 在选择题中属于中等难度，需要理解HT150和20钢的机械加工性能概念，并进行比较分析。虽然题目涉及两种材料的比较，但在选择题型中，只需识别出正确选项，不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "The machinability of HT150 is better than that of 20 steel.", "choice_question": "Compare the machinability of HT150 and annealed 20 steel.", "conversion_reason": "The answer is a clear and definitive statement that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "HT150 has better machinability due to its higher graphite content improving chip formation", "B": "Annealed 20 steel is superior because its lower carbon content reduces tool wear", "C": "Both materials show similar machinability as they have comparable hardness after heat treatment", "D": "20 steel is better because its higher tensile strength leads to cleaner cutting surfaces" }, "correct_answer": "A", "explanation": "Correct answer A is justified by HT150's graphite flakes acting as built-in chip breakers and lubricants. Option B exploits the carbon content misconception - while lower carbon generally improves machinability, annealed 20 steel's ferrite-pearlite structure is worse than HT150's graphite structure. Option C creates a hardness trap - though hardness values may overlap, graphite's presence is the dominant factor. Option D uses tensile strength as a red herring, as it's irrelevant to machinability compared to microstructure effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4135, "question": "This ceramic outlier has the highest room-temperature thermal conductivity of about 2,000 watts per meter per kelvin, a value that is five time higher than the best thermally conductive metals.\n(a) \\mathrm{Al}_{2} \\mathrm{O}_{3}\n(b) \\mathrm{CaF}_{2}\n(c) \\mathrm{TiO}_{2}\n(d) \\mathrm{SrTiO}_{3}\n(e) C (diamond)", "answer": "Diamond has the highest thermal conductivity of these options.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择具有最高室温热导率的陶瓷材料，答案形式为选择特定选项。 | 知识层次: 题目考查对材料热导率这一基本概念的记忆和理解，特别是对特定材料（如金刚石）的热导率特性的记忆。题目不涉及复杂的计算或分析，只需从选项中识别出具有最高热导率的材料。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需识别具有最高室温热导率的陶瓷材料。正确选项（diamond）是常见的高热导率材料，属于直接记忆性知识，无需复杂分析或理解多个概念。", "convertible": true, "correct_option": "C (diamond)", "choice_question": "This ceramic outlier has the highest room-temperature thermal conductivity of about 2,000 watts per meter per kelvin, a value that is five time higher than the best thermally conductive metals.", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provided corresponds to one of the given options (e). Therefore, it can be directly converted to a single-choice question by identifying the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Wiedemann-Franz law holds precisely for all metals at room temperature", "B": "Phonon contribution dominates thermal conductivity in pure copper at 300K", "C": "The thermal conductivity of graphene is primarily limited by electron-phonon scattering", "D": "In covalently bonded ceramics, thermal conductivity always increases with temperature" }, "correct_answer": "A", "explanation": "Correct answer is A because the Wiedemann-Franz law is only approximately valid for metals and deviations occur due to inelastic scattering. Option B exploits the common misconception that metals' thermal conductivity is always electronic - in pure Cu at 300K, phonons contribute about 2%. Option C targets graphene's unusual properties - its thermal conductivity is actually limited by phonon-phonon scattering. Option D creates a false generalization - many covalent ceramics show decreasing thermal conductivity with temperature due to phonon-phonon interactions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1177, "question": "What are the two metallographic morphologies of martensite in quenched steel?", "answer": "Lath martensite and acicular martensite", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举淬火钢中马氏体的两种金相形态，答案需要提供具体的文字描述而非选择或判断 | 知识层次: 题目考查马氏体在淬火钢中的两种金相形态的记忆，属于基础概念的分类和记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆马氏体的两种基本金相形态（板条马氏体和针状马氏体），属于最基础的定义性知识。题目不涉及概念解释或复杂体系阐述，仅需简单回忆即可作答，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Lath martensite and acicular martensite", "choice_question": "Which of the following are the two metallographic morphologies of martensite in quenched steel?", "conversion_reason": "The answer is a standard terminology and can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Lath martensite and acicular martensite", "B": "Plate martensite and twinned martensite", "C": "Bainitic martensite and tempered martensite", "D": "Ferritic martensite and austenitic martensite" }, "correct_answer": "A", "explanation": "The correct answer is A because lath and acicular are the two fundamental morphologies observed in quenched steel. Option B uses real terms (plate/twinned) but describes substructure features rather than primary morphologies. Option C combines incorrect phase terminology (bainite is not a martensite type) with a processing state (tempered). Option D falsely suggests phase-based classifications that don't exist for martensite.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1379, "question": "What effect will tertiary cementite have on the mechanical properties of iron-carbon alloys?", "answer": "Increases hardness and strength but reduces toughness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述第三渗碳体对铁碳合金机械性能的影响，答案提供了文字解释而非选择或判断 | 知识层次: 题目需要理解三次渗碳体对铁碳合金机械性能的影响，涉及多个概念（硬度、强度、韧性）的关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及铁碳合金中三次渗碳体对机械性能的影响，要求考生掌握渗碳体的基本特性及其对硬度、强度和韧性的不同作用机制。虽然不需要多步计算，但需要综合分析不同性能指标的变化趋势，属于概念关联和综合分析层次。", "convertible": true, "correct_option": "Increases hardness and strength but reduces toughness", "choice_question": "What effect will tertiary cementite have on the mechanical properties of iron-carbon alloys?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases hardness and strength but reduces toughness", "B": "Decreases hardness while improving ductility and impact resistance", "C": "Has negligible effect due to its extremely small volume fraction", "D": "Improves both strength and toughness by refining grain structure" }, "correct_answer": "A", "explanation": "Tertiary cementite forms along grain boundaries and increases hardness/strength through dispersion strengthening, but reduces toughness by creating stress concentration points. Option B is a cognitive bias trap - while cementite does reduce toughness, it increases hardness. Option C exploits the small volume fraction misconception, but ignores its disproportionate effect on grain boundaries. Option D is a grain refinement red herring - while grain refinement can improve both properties, cementite itself does not refine grains.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 720, "question": "Generally speaking, grain boundaries are the main diffusion channels for pores to reach the exterior of the sintered body.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征。 | 知识层次: 题目考查对晶界作为烧结体中孔隙扩散主要通道这一基本概念的记忆和理解，属于基础概念记忆层次。 | 难度: 该题目属于基础概念正误判断题，仅需记忆晶界是烧结体中孔隙扩散的主要通道这一基本原理即可作答，无需深入理解或分析多个概念，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "√", "choice_question": "Generally speaking, grain boundaries are the main diffusion channels for pores to reach the exterior of the sintered body.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all polycrystalline materials, grain boundaries always exhibit higher diffusion coefficients than the bulk lattice at any temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While grain boundaries generally have higher diffusion coefficients than the bulk lattice, this is not universally true at all temperatures. At very high temperatures approaching the melting point, bulk diffusion may become dominant due to increased thermal energy overcoming lattice activation barriers. The absolute term 'always' makes this statement false. Additionally, some specially engineered materials may have unique diffusion characteristics that deviate from this general trend.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 135, "question": "CeO2 has a fluorite structure. When 15 mol% CaO is added to form a solid solution, the measured density of the solid solution is d = 7.01 g/cm³, and the unit cell parameter is a = 0.5417 nm. Determine through calculation which type of solid solution is formed. The atomic weights are Ce 140.12, Ca 40.08, O 16.00.", "answer": "For the CaO-CeO2 solid solution, from the perspective of maintaining electrical neutrality, it can form either an oxygen vacancy solid solution or a solid solution with Ca²⁺ embedded in the anion interstitial sites. The solid solution equations are as follows: For substitutional solid solution, x = 0.15, 1 - x = 0.85, 2 - x = 1.85, so the chemical formula of the substitutional solid solution is Ca0.15Ce0.85O1.85. Since CeO2 has a fluorite structure, the number of unit cell molecules Z = 4, and the unit cell contains three types of ions: Ca²⁺, Ce⁴⁺, and O²⁻. The mass of the unit cell is: W = ΣWi = [4 × (0.15/1) × MCa²⁺ + 4 × (0.85/1) × MCe⁴⁺ + 8 × (1.85/2) × MO²⁻] / 6.022 × 10²² = 102.766 × 10⁻²² g. The calculated density dR = W/V = 0.6465 g/cm³. For interstitial solid solution, the chemical formula is Ca2Ce1-yO2. Compared with the given composition Ca0.15Ce0.85O1.85, the O²⁻ content differs: Ca0.15Ce0.85O1.85 → Ca0.15×2/1.85Ce0.85×2/1.85O2. y = 0.15 × 2 / 1.85, 1 - y = 0.85 × 2 / 1.85 ⇒ y = 0.15 / 1.85. The chemical formula of the interstitial solid solution is Ca0.15×2/1.85Ce1.7/1.85O2. Similarly, the calculated density dg = W/V = 7.033 g/cm³. The measured density is d = 7.01 g/cm³, which is close to d2. Therefore, an interstitial solid solution is formed, with interstitial Ca²⁺ ions present.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过计算确定形成的固溶体类型，涉及密度、晶胞参数和原子量的计算，答案中展示了详细的公式应用和数值计算过程。 | 知识层次: 题目需要进行多步计算，包括化学式的推导、单位晶胞质量的计算、密度的计算等，同时需要理解固溶体的形成机制和电中性原则，涉及多个概念的关联和综合分析。 | 难度: 在选择题中属于高难度，题目涉及复杂的多步计算和概念关联。需要考生掌握固体溶液的形成机制、密度计算、晶胞参数与化学组成的关联等知识点，并进行综合分析。计算过程涉及多个变量和步骤，包括化学式的推导、单位晶胞质量的计算、密度的比较等，对考生的综合能力和计算精度要求较高。", "convertible": true, "correct_option": "an interstitial solid solution is formed, with interstitial Ca²⁺ ions present", "choice_question": "CeO2 has a fluorite structure. When 15 mol% CaO is added to form a solid solution, the measured density of the solid solution is d = 7.01 g/cm³, and the unit cell parameter is a = 0.5417 nm. Determine which type of solid solution is formed.", "conversion_reason": "The original question is a calculation problem with a definitive answer that can be presented as a choice in a multiple-choice format. The correct option is derived from the detailed calculation provided in the answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An interstitial solid solution is formed, with interstitial Ca²⁺ ions present", "B": "A substitutional solid solution is formed, with Ca²⁺ substituting for Ce⁴⁺", "C": "A vacancy solid solution is formed, with oxygen vacancies compensating for charge imbalance", "D": "A complex defect cluster solution is formed, with both cation substitution and anion vacancies" }, "correct_answer": "A", "explanation": "The correct answer is A because the density calculation shows fewer formula units per unit cell than expected for pure CeO2, indicating interstitial incorporation of Ca²⁺. Option B is a cognitive bias trap - it seems plausible due to similar ionic radii but contradicts density data. Option C exploits the common knowledge that CeO2 often forms oxygen vacancies, but the density proves this isn't the dominant mechanism here. Option D is a multi-level verification trap - it combines partially correct concepts but doesn't match the experimental density measurements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2207, "question": "There are three types of ingots: pure Ti, Al, and Pb. It is known that the melting point of Ti is 1672°C, with a hexagonal close-packed structure below 883°C and a face-centered cubic structure above 883°C; the melting point of Al is 660°C, with a face-centered cubic structure; the melting point of Pb is 328°C, with a face-centered cubic structure. Determine the order of their rolling difficulty at room temperature (20°C).", "answer": "At room temperature, Pb is the easiest to roll, followed by Al, and Ti is the most difficult.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求根据材料的结构和性质进行解释和论述，最终得出一个排序结论，而不是从选项中选择或进行数值计算。 | 知识层次: 题目需要综合运用金属的晶体结构、相变温度和室温下的力学性能等知识，通过分析不同金属在室温下的晶体结构（如Ti的HCP结构在室温下更难变形，而Al和Pb的FCC结构相对容易变形）来推断其轧制难度。这涉及多步推理和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握不同金属的晶体结构、熔点以及这些性质对室温下轧制难度的影响。解题步骤包括识别各金属的晶体结构、分析其室温下的塑性变形能力，并进行综合比较。虽然不涉及复杂计算，但需要将多个材料科学概念关联起来，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "Pb is the easiest to roll, followed by Al, and Ti is the most difficult.", "choice_question": "At room temperature (20°C), determine the order of rolling difficulty for the following ingots: pure Ti, Al, and Pb.", "conversion_reason": "The answer is a standard and specific order, which can be directly used as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pb > Al > Ti", "B": "Al > Pb > Ti", "C": "Ti > Al > Pb", "D": "Al > Ti > Pb" }, "correct_answer": "C", "explanation": "The correct order is Ti > Al > Pb because: 1) Ti has a hexagonal close-packed structure at room temperature which has fewer slip systems than FCC metals, making it harder to deform; 2) Among FCC metals, Pb has lower melting point (328°C) than Al (660°C), indicating weaker atomic bonds and easier deformation. Distractors exploit: A) Incorrectly assumes higher atomic number means easier deformation; B) Misleads by suggesting Al is harder than Pb due to its industrial importance; D) Tricks by making Ti appear intermediate based on its position in periodic table rather than crystal structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4927, "question": "An iron bar magnet having a coercivity of 7000 A/m is to be demagnetized. If the bar is inserted within a cylindrical wire coil 0.25m long and having 150 turns, what electric current is required to generate the necessary magnetic field?", "answer": "11.7A", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，要求计算所需的电流值，答案是一个具体的数值（11.7A），解答过程涉及物理公式和单位转换。 | 知识层次: 题目需要进行多步计算（计算磁场强度、应用安培定律等），涉及概念关联（磁场强度与电流的关系），并需要综合分析（将磁体的矫顽力与线圈参数联系起来）。虽然不涉及复杂的推理或创新设计，但超出了简单应用的范围。 | 难度: 在选择题中属于中等偏上难度，需要理解磁滞回线、磁场强度与电流的关系等概念，并进行多步计算（包括单位换算和公式应用）。虽然题目提供了明确的计算路径，但涉及多个物理概念的关联运用，比单纯记忆性题目更具挑战性。", "convertible": true, "correct_option": "11.7A", "choice_question": "An iron bar magnet having a coercivity of 7000 A/m is to be demagnetized. If the bar is inserted within a cylindrical wire coil 0.25m long and having 150 turns, what electric current is required to generate the necessary magnetic field?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "11.7A", "B": "23.3A", "C": "5.8A", "D": "46.6A" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula H = NI/L, where H is coercivity (7000 A/m), N is number of turns (150), I is current, and L is coil length (0.25m). Solving gives I = HL/N = 7000*0.25/150 = 11.7A. Option B doubles the correct value by incorrectly assuming the coercivity needs to be exceeded by 100%. Option C halves the correct value by mistakenly dividing the coercivity by 2. Option D quadruples the correct value by incorrectly considering both length and turns count need to be doubled.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3264, "question": "As an economic measure, using pure lead instead of lead-tin alloy to make solder for brazing iron, how is the wettability of pure lead on iron?", "answer": "The wettability of pure lead on iron is poor.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释纯铅在铁上的润湿性，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对纯铅在铁上润湿性的基本概念记忆和理解，属于基础知识的直接应用，不需要复杂的分析或推理。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅考察对纯铅在铁上润湿性的基础概念记忆，不需要解释或分析过程，只需回忆\"纯铅润湿性差\"这一基本事实即可作答。正确选项直接给出了定义性结论，没有涉及概念比较或复杂推理过程。", "convertible": true, "correct_option": "The wettability of pure lead on iron is poor.", "choice_question": "As an economic measure, using pure lead instead of lead-tin alloy to make solder for brazing iron, how is the wettability of pure lead on iron?", "conversion_reason": "The answer is a standard statement that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Excellent wettability due to lead's low surface tension", "B": "Moderate wettability similar to lead-tin alloys", "C": "Poor wettability due to high contact angle with iron", "D": "Variable wettability depending on temperature only" }, "correct_answer": "C", "explanation": "The correct answer is C because pure lead forms a high contact angle with iron due to poor chemical compatibility and lack of tin's wetting-promoting effects. Option A exploits the common misconception that low surface tension always ensures good wettability. Option B creates false analogy with lead-tin alloys where tin dramatically improves wetting. Option D introduces a temperature-only dependency trap, ignoring fundamental interfacial chemistry factors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1756, "question": "When a cubic close packing is formed by n spheres, what is the number of tetrahedral voids?", "answer": "2n", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求计算立方紧密堆积中四面体空隙的数量，需要应用材料科学中的相关公式和概念，最终答案是一个具体的数值（2n），属于计算题的特征。 | 知识层次: 题目考查对立方紧密堆积中四面体空隙数量的基本公式应用，只需直接套用\"四面体空隙数量=2n\"的结论进行计算，属于简单应用层次。 | 难度: 在选择题中属于简单公式应用计算难度，题目直接考察立方密堆积中四面体空隙数量的基本公式应用（2n），无需复杂推导或多步骤计算，属于单一知识点直接套用类型。", "convertible": true, "correct_option": "2n", "choice_question": "When a cubic close packing is formed by n spheres, what is the number of tetrahedral voids?", "conversion_reason": "The answer is a specific numerical value (2n), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "2n", "C": "选项D", "D": "选项B" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 2728, "question": "Calculate the dislocation density ρ when the shear strength is $42\\mathrm{MPa}$.", "answer": "The dislocation density ρ can be calculated using the formula ρ = (τ̄/αGb)^2, where α is a constant (typically taken as 0.5). Substituting τ̄ = 42×10^6 Pa, G = 50×10^9 Pa, and b = 3.12×10^-10 m, we obtain ρ = (42×10^6 / (0.5×50×10^9×3.12×10^-10))^2 ≈ 7.3×10^12 m^-2.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出一个具体的数值结果（dislocation density ρ），这符合计算题的特征。 | 知识层次: 题目要求直接套用公式进行数值计算，涉及基本的材料科学参数和简单的代数运算，无需多步推导或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要代入多个已知参数并进行计算，但整个过程仅涉及单一公式的直接套用，没有复杂的推导或多步骤组合。学生只需正确识别公式并准确代入数值即可得出答案，符合等级2的简单应用要求。", "convertible": true, "correct_option": "7.3×10^12 m^-2", "choice_question": "Calculate the dislocation density ρ when the shear strength is $42\\mathrm{MPa}$. The dislocation density ρ can be calculated using the formula ρ = (τ̄/αGb)^2, where α is a constant (typically taken as 0.5). Substituting τ̄ = 42×10^6 Pa, G = 50×10^9 Pa, and b = 3.12×10^-10 m, the dislocation density ρ is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.3×10^12 m^-2", "B": "3.2×10^14 m^-2", "C": "42×10^9 m^-2", "D": "1.5×10^11 m^-2" }, "correct_answer": "A", "explanation": "正确答案A是通过正确代入公式ρ = (τ̄/αGb)^2计算得出的。干扰项B利用了常见的数量级直觉错误，将剪切模量G的单位误用为GPa而非Pa。干扰项C直接使用了给定的剪切强度数值，制造表面相关性陷阱。干扰项D则通过错误使用α=1而非0.5来制造计算偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2340, "question": "Calculate the ratio of the atomic radius when the coordination number of the elemental atom is 6 to that when the coordination number is 12.", "answer": "Since the molar volumes are equal for coordination numbers 6 and 12, according to the packing density relation: η12Vmol=(4NAπr123)/3, η6Vmol=(4NAπr63)/3. Dividing the two equations gives: r6/r12=(η6/η12)1/3=(0.52/0.74)1/3=0.89", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案中包含了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及协调数与原子半径的关系，并需要理解摩尔体积相等的条件。虽然计算过程相对直接，但需要综合运用多个概念和公式，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解原子半径与配位数的关系、摩尔体积的概念，并应用堆积密度公式进行多步计算。虽然题目提供了关键公式，但需要正确推导比例关系并代入数值计算，涉及多个概念的综合运用和数学处理能力。", "convertible": true, "correct_option": "0.89", "choice_question": "What is the ratio of the atomic radius when the coordination number of the elemental atom is 6 to that when the coordination number is 12?", "conversion_reason": "The calculation yields a specific numerical answer (0.89), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.89", "B": "1.12", "C": "0.71", "D": "1.26" }, "correct_answer": "A", "explanation": "The correct answer is 0.89, derived from the ratio of atomic radii in face-centered cubic (CN=12) to body-centered cubic (CN=8) structures, adjusted for coordination number effects. Option B (1.12) reverses the ratio, exploiting a common calculation reversal error. Option C (0.71) mimics the FCC-BCC packing factor ratio, a classic coordination number confusion. Option D (1.26) approximates the square root of 1.6, a frequent misapplication of geometric relationships in atomic packing calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1208, "question": "Burgers vector", "answer": "Burgers vector: A physical quantity used to describe the lattice distortion caused by dislocations. The magnitude of this vector represents the strength of the dislocation, indicating the total extent of lattice distortion, while its direction represents the direction of lattice point distortion. Generally, the larger this vector is, the greater the degree of crystal distortion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对Burgers vector进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查Burgers vector的基本定义、物理意义和基本特性，属于基础概念的记忆和理解范畴，不涉及复杂应用或综合分析。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆Burgers vector的定义、物理意义及其在描述位错引起的晶格畸变中的作用。虽然涉及多个概念（如晶格畸变、位错强度等），但整体上仍属于基础概念的记忆和解释范畴，不需要复杂的分析或比较步骤。因此，难度等级为2。", "convertible": true, "correct_option": "A physical quantity used to describe the lattice distortion caused by dislocations. The magnitude of this vector represents the strength of the dislocation, indicating the total extent of lattice distortion, while its direction represents the direction of lattice point distortion. Generally, the larger this vector is, the greater the degree of crystal distortion.", "choice_question": "Which of the following best describes the Burgers vector?", "conversion_reason": "The answer is a standard definition of the Burgers vector, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A physical quantity used to describe the lattice distortion caused by dislocations. The magnitude of this vector represents the strength of the dislocation, indicating the total extent of lattice distortion, while its direction represents the direction of lattice point distortion. Generally, the larger this vector is, the greater the degree of crystal distortion.", "B": "A vector quantity representing the slip direction in a crystal lattice during plastic deformation. Its magnitude equals the interatomic spacing in the slip direction, and its direction is always parallel to the dislocation line.", "C": "A mathematical construct used to quantify the elastic strain field around a dislocation. Its components correspond to the principal strains in the distorted lattice region.", "D": "A topological invariant characterizing the Burgers circuit around a dislocation. Its value depends on the crystal structure type but is independent of the specific dislocation configuration." }, "correct_answer": "A", "explanation": "Option A is correct as it accurately describes the Burgers vector's role in quantifying lattice distortion caused by dislocations, including both magnitude and directional information. Option B is misleading by incorrectly stating the Burgers vector is always parallel to the dislocation line (only true for screw dislocations) and oversimplifying its magnitude. Option C confuses the Burgers vector with the strain tensor components. Option D misrepresents it as a topological invariant rather than a physical distortion measure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 100, "question": "For screw dislocations, what are the characteristics of the dislocation line direction, Burgers vector, and dislocation motion direction?", "answer": "Screw dislocation: the dislocation line is parallel to the Burgers vector, and the dislocation line is parallel to the direction of dislocation motion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和描述螺位错的特征，包括位错线方向、Burgers矢量和位错运动方向之间的关系，答案以文字解释的形式给出，符合简答题的特点。 | 知识层次: 题目考查对螺位错基本特征（位错线方向、伯氏矢量、位错运动方向）的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅要求记忆和识别螺位错的基本特征（位错线方向、伯氏矢量方向、运动方向之间的关系），属于基础概念的直接回忆，无需解释或复杂分析。", "convertible": true, "correct_option": "the dislocation line is parallel to the Burgers vector, and the dislocation line is parallel to the direction of dislocation motion", "choice_question": "For screw dislocations, which of the following correctly describes the characteristics of the dislocation line direction, Burgers vector, and dislocation motion direction?", "conversion_reason": "The answer is a standard description of the characteristics of screw dislocations, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "the dislocation line is parallel to the Burgers vector, and the dislocation line is parallel to the direction of dislocation motion", "B": "the dislocation line is perpendicular to the Burgers vector, and the dislocation line is parallel to the direction of dislocation motion", "C": "the dislocation line is parallel to the Burgers vector, but the dislocation line is perpendicular to the direction of dislocation motion", "D": "the dislocation line is perpendicular to the Burgers vector, and the dislocation line is perpendicular to the direction of dislocation motion" }, "correct_answer": "A", "explanation": "For screw dislocations, the dislocation line direction is parallel to the Burgers vector, and the dislocation motion direction is also parallel to the dislocation line. Option B incorrectly states that the dislocation line is perpendicular to the Burgers vector, which is a characteristic of edge dislocations. Option C creates confusion by mixing parallel and perpendicular relationships, exploiting the AI's potential to misapply vector relationships. Option D describes edge dislocation characteristics, capitalizing on the AI's possible confusion between screw and edge dislocation properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2124, "question": "What is the difference between a vertical section of a ternary phase diagram and a binary phase diagram?", "answer": "The most fundamental difference between the two is that a binary phase diagram is a graphical representation of phase equilibrium in a binary system, directly reflecting the phase equilibrium relationships in the binary system. In contrast, a vertical section of a ternary phase diagram is merely an intersection of a specific plane with the ternary phase diagram and generally does not reflect the phase equilibrium relationships in the ternary system. However, if the vertical section happens to pass through the line connecting a pure component-stable compound or stable compound-stable compound composition points (for example, the SiO2-Al2O3 phase diagram is a vertical section of the Si-Al-O phase diagram), in such a vertical section diagram, the stable compound is treated as a component, and the vertical section diagram reflects the phase equilibrium relationships in the ternary system.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述垂直截面图和二元相图的区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释二元相图和三元相图垂直截面的区别，涉及对相图基本概念的理解和比较，需要综合分析两种相图的特点及其应用场景。虽然不涉及复杂计算或深度推理，但需要对相图的基本原理和具体应用有一定的理解和关联能力。 | 难度: 在选择题型内，该题目属于较高难度，原因如下：", "convertible": true, "correct_option": "The most fundamental difference between the two is that a binary phase diagram is a graphical representation of phase equilibrium in a binary system, directly reflecting the phase equilibrium relationships in the binary system. In contrast, a vertical section of a ternary phase diagram is merely an intersection of a specific plane with the ternary phase diagram and generally does not reflect the phase equilibrium relationships in the ternary system. However, if the vertical section happens to pass through the line connecting a pure component-stable compound or stable compound-stable compound composition points (for example, the SiO2-Al2O3 phase diagram is a vertical section of the Si-Al-O phase diagram), in such a vertical section diagram, the stable compound is treated as a component, and the vertical section diagram reflects the phase equilibrium relationships in the ternary system.", "choice_question": "What is the difference between a vertical section of a ternary phase diagram and a binary phase diagram?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": "None", "perplexity_level": "None", "perplexity_reason": "The question clearly asks for the difference between a vertical section of a ternary phase diagram and a binary phase diagram, and the correct option provides a detailed and clear explanation. There are no ambiguous references, missing key information, or dependencies on external context that are not provided.", "missing_info": "None" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A vertical section of a ternary diagram can never represent true phase equilibria, while a binary diagram always does", "B": "Binary diagrams show temperature-composition relationships, while ternary vertical sections show pressure-composition relationships", "C": "The main difference is that binary diagrams have two independent variables, while ternary vertical sections have three", "D": "Vertical sections of ternary diagrams are projections of 3D space onto 2D, while binary diagrams are inherently 2D representations" }, "correct_answer": "A", "explanation": "Option A is correct because it captures the fundamental distinction that only certain special vertical sections (those aligned with stable compound compositions) can represent true equilibria, while binary diagrams always do. Option B is incorrect by introducing pressure as a variable, exploiting AI's tendency to overgeneralize thermodynamic parameters. Option C is wrong about variable counts, playing on AI's difficulty with dimensional analysis in phase diagrams. Option D sounds plausible but misrepresents vertical sections as projections rather than intersections, exploiting visualization misconceptions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4331, "question": "Consider 1.0 kg of austenite containing 1.15 wt % C, cooled to below 727 C (1341 F). How many kilograms each of pearlite and the proeutectoid phase form?", "answer": "the pearlite formed is 0.93 kg, and the proeutectoid phase (cementite) formed is 0.07 kg.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算以确定珠光体和先共析相的重量，答案提供了具体的计算结果（0.93 kg和0.07 kg），这符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要理解相图、杠杆定律的应用，并进行综合分析以确定珠光体和先共析相的重量分数。 | 难度: 在选择题中属于中等偏上难度，需要理解相图概念、杠杆定律应用以及多步计算过程。虽然题目提供了正确选项，但解题过程涉及：", "convertible": true, "correct_option": "the pearlite formed is 0.93 kg, and the proeutectoid phase (cementite) formed is 0.07 kg", "choice_question": "Consider 1.0 kg of austenite containing 1.15 wt % C, cooled to below 727 C (1341 F). How many kilograms each of pearlite and the proeutectoid phase form?", "conversion_reason": "The question is a calculation problem with a specific and definitive answer, making it suitable for conversion into a multiple-choice format. The correct option can be directly derived from the given answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pearlite: 0.93 kg, Proeutectoid cementite: 0.07 kg", "B": "Pearlite: 0.85 kg, Proeutectoid ferrite: 0.15 kg", "C": "Pearlite: 0.97 kg, Proeutectoid cementite: 0.03 kg", "D": "Pearlite: 0.89 kg, Proeutectoid ferrite: 0.11 kg" }, "correct_answer": "A", "explanation": "The correct answer uses the lever rule calculation for a hypereutectoid steel (1.15 wt% C). At 727°C, the eutectoid composition is 0.76 wt% C. The proeutectoid cementite forms first, then the remaining austenite transforms to pearlite. Option B incorrectly assumes proeutectoid ferrite forms (common mistake for hypoeutectoid steels). Option C underestimates cementite by using the wrong lever rule application. Option D combines both errors - wrong phase (ferrite) and incorrect mass fractions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 254, "question": "When Zn2+ diffuses in ZnS, the diffusion coefficient at 563°C is 3×10−4cm2/s, and at 450°C it is 1.0×10−4cm2/s. Calculate the activation energy for diffusion and D0.", "answer": "Referring to 7-4, Q=48856J/mol, D0=3×10−15cm2/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的温度与扩散系数数据，计算扩散激活能（activation energy）和D0值。解答过程涉及数值计算和公式应用（如阿伦尼乌斯方程），答案以具体数值形式给出。 | 知识层次: 题目需要应用扩散系数的阿伦尼乌斯公式进行多步计算，涉及温度与扩散系数的关系，并求解活化能和D0值。这需要理解扩散机制的基本原理，并能正确关联和运用相关公式进行计算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要应用阿伦尼乌斯公式进行两步计算（先求活化能Q，再求D0），涉及对数运算和单位转换。虽然题目提供了关键数据，但需要考生正确关联温度与扩散系数的关系，并执行连贯的数学推导步骤。相比单纯的概念选择题，此类计算题在选择题型中复杂度较高，但尚未达到多变量交互作用的最高难度等级。", "convertible": true, "correct_option": "Q=48856J/mol, D0=3×10−15cm2/s", "choice_question": "When Zn2+ diffuses in ZnS, the diffusion coefficient at 563°C is 3×10−4cm2/s, and at 450°C it is 1.0×10−4cm2/s. The activation energy for diffusion and D0 are:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Q=48856J/mol, D0=3×10−15cm2/s", "B": "Q=32570J/mol, D0=1×10−12cm2/s", "C": "Q=41200J/mol, D0=5×10−14cm2/s", "D": "Q=55000J/mol, D0=8×10−16cm2/s" }, "correct_answer": "A", "explanation": "正确答案A通过Arrhenius方程精确计算得出。干扰项B利用常见错误直觉设置较低的激活能和较高的D0；干扰项C采用中间值制造'中庸陷阱'；干扰项D通过夸大激活能同时缩小D0来制造'补偿效应'错觉。这些干扰项都利用了材料科学中对扩散参数关系的典型误解。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4001, "question": "Does increasing temperature favor brittle fracture in polymers?", "answer": "No, increasing temperature does not favor brittle fracture in polymers.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（对/错），答案直接给出了判断结果（No），符合判断题的特征 | 知识层次: 题目考查对聚合物断裂行为与温度关系的基本概念记忆，属于基础原理的直接应用，无需复杂分析或计算。 | 难度: 该题目属于基础概念正误判断题，仅需记忆温度对聚合物断裂性能的基本影响原理。在选择题型中，这属于最简单的难度等级，因为只需识别\"温度升高不利于聚合物脆性断裂\"这一基本事实，无需深入理解或分析多个概念。", "convertible": true, "correct_option": "No, increasing temperature does not favor brittle fracture in polymers.", "choice_question": "Does increasing temperature favor brittle fracture in polymers?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All polymers become more brittle when cooled below their glass transition temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many amorphous polymers do become more brittle below their glass transition temperature (Tg), this is not universally true for all polymers. Some semi-crystalline polymers may maintain toughness below Tg due to their crystalline regions. Additionally, certain rubber-toughened polymers are specifically designed to resist brittle fracture at low temperatures. The use of 'all' in this statement makes it incorrect.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4814, "question": "Steady-state creep rate data are given in the following table for a nickel alloy at 538^{\\circ} C \\\\ (811 K):\n\\begin{tabular}{lc}\n\\hline \\dot{\\varepsilon}_{s}\\left(h^{-1}\\right) & \\sigma(M P(a) \\\\\n\\hline 10^{-7} & 22.0 \\\\\n10^{-6} & 36.1 \\\\\n\\hline\n\\end{tabular}\nCompute the stress at which the steady-state creep is 10^{-5}h^{-1} (also at 538^{\\circ} C ).", "answer": "the stress at which the steady-state creep is 10^{-5}h^{-1} is 59.4 MPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的数据和公式计算特定条件下的应力值，答案是一个具体的数值结果，解答过程涉及数值计算和公式应用。 | 知识层次: 题目需要进行多步计算，包括对稳态蠕变速率的对数处理、应力与蠕变速率关系的分析（如幂律蠕变方程的运用），以及通过已有数据点求解未知应力值。这需要理解蠕变行为的基本原理，并能将概念与数学计算相结合，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解稳态蠕变速率与应力之间的关系，并进行多步计算。题目要求根据给定的数据点，通过插值或外推方法计算新的应力值，涉及对数坐标下的线性关系分析。虽然计算步骤相对明确，但需要综合应用材料科学中的蠕变概念和数学计算能力。", "convertible": true, "correct_option": "59.4 MPa", "choice_question": "Given the steady-state creep rate data for a nickel alloy at 538°C (811 K) in the table below, compute the stress at which the steady-state creep is 10^{-5}h^{-1} (also at 538°C).\n\n\\begin{tabular}{lc}\n\\hline \\dot{\\varepsilon}_{s}\\left(h^{-1}\\right) & \\sigma(M P(a) \\\\\n\\hline 10^{-7} & 22.0 \\\\\n10^{-6} & 36.1 \\\\\n\\hline\n\\end{tabular}", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "59.4 MPa", "B": "48.2 MPa", "C": "72.3 MPa", "D": "36.1 MPa" }, "correct_answer": "A", "explanation": "正确答案A是通过对给定数据点进行对数-对数线性回归计算得出的，符合幂律蠕变方程。干扰项B设计为基于简单线性外推的错误结果，利用了认知偏差。干扰项C利用了专业直觉陷阱，故意放大了应力敏感性指数的影响。干扰项D直接取用了表格中的最高应力值，是最明显的直觉陷阱选项。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4613, "question": "An iron bar magnet having a coercivity of 4000 \\mathrm{~A} / m is to be demagnetized. If the bar is inserted within a cylindrical wire coil 0.15{m} long and having 100 turns, what electric current is required to generate the necessary magnetic field?", "answer": "the required electric current is 6 \\mathrm{a}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定所需的电流值。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即根据给定的参数（矫顽力、线圈长度和匝数）直接套用公式计算所需的电流。不需要多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（H = nI/l）进行计算，解题步骤简单，属于最基础的难度等级。", "convertible": true, "correct_option": "6 A", "choice_question": "An iron bar magnet with a coercivity of 4000 A/m is to be demagnetized. If the bar is inserted within a cylindrical wire coil 0.15 m long and having 100 turns, what electric current is required to generate the necessary magnetic field?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6 A", "B": "4 A", "C": "8 A", "D": "10 A" }, "correct_answer": "A", "explanation": "The correct answer is A (6 A) because the required magnetic field strength (H) is equal to the coercivity (4000 A/m). Using the formula H = (N*I)/L, where N is the number of turns (100), I is the current, and L is the coil length (0.15 m), solving for I gives I = (H*L)/N = (4000*0.15)/100 = 6 A. Option B (4 A) is a common error from incorrectly using L=0.1 m. Option C (8 A) results from miscalculating the turns as 75. Option D (10 A) comes from forgetting to divide by the coil length.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3604, "question": "Determine the planar density for BCC lithium in the (100) plane.", "answer": "planar density = 0.0812 x 10^16 points/cm^2", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算BCC锂在(100)晶面的面密度，需要应用公式进行数值计算，答案以数值形式给出。 | 知识层次: 题目需要计算BCC锂在(100)面的平面密度，涉及晶体结构知识、原子位置确定、面积计算等多步操作，需要将晶体学概念与数学计算相结合，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构、(100)晶面特征、平面密度计算公式等多个概念，并进行多步计算（包括晶格常数推导、原子位置确定、有效原子数计算等）。虽然题目提供了正确选项减少了部分计算量，但仍需要较强的综合分析能力才能正确解题。", "convertible": true, "correct_option": "0.0812 x 10^16 points/cm^2", "choice_question": "What is the planar density for BCC lithium in the (100) plane?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0812 x 10^16 points/cm^2", "B": "0.0406 x 10^16 points/cm^2", "C": "0.1624 x 10^16 points/cm^2", "D": "0.0573 x 10^16 points/cm^2" }, "correct_answer": "A", "explanation": "The correct answer is A because the planar density for BCC lithium in the (100) plane is calculated by considering the number of atoms per unit area on that plane. For BCC, the (100) plane contains 1 atom (shared by 4 unit cells) per unit area. Option B is half of the correct value, exploiting the common mistake of not accounting for the full atom contribution. Option C is double the correct value, targeting those who might incorrectly consider two atoms per plane. Option D is derived from an incorrect lattice parameter calculation, appealing to those who might miscalculate the unit cell dimensions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1324, "question": "Dendritic segregation", "answer": "Dendritic segregation: It is a type of microsegregation in materials, where under non-equilibrium cooling conditions, the newly formed solid solution grains after a homogeneous transformation exhibit non-uniform composition within. The initially crystallized core contains more high-melting-point component atoms, while the later crystallized outer regions contain more low-melting-point component atoms. Typically, solid solution crystals grow in a dendritic manner, resulting in the dendrite arms containing more high-melting-point components and the interdendritic regions containing more low-melting-point component atoms. This leads to compositional inhomogeneity within the same grain.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Dendritic segregation\"进行详细的文字解释和论述，答案提供了概念定义、形成机制和具体表现等详细说明，符合简答题的特征。 | 知识层次: 题目考查的是对\"Dendritic segregation\"这一基本概念的定义和描述，属于材料科学中关于微观偏析的基础知识。答案主要涉及对现象的定义、形成原因和特征的记忆性解释，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生对\"枝晶偏析\"的定义、形成原因及其在材料中的具体表现有较为全面的理解。题目不仅要求记忆定义，还需要理解非平衡冷却条件下固溶体晶粒的成分不均匀性及其与枝晶生长方式的关系。这种程度的描述性解释在选择题中属于概念解释和描述级别，比单纯的定义简答（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Dendritic segregation: It is a type of microsegregation in materials, where under non-equilibrium cooling conditions, the newly formed solid solution grains after a homogeneous transformation exhibit non-uniform composition within. The initially crystallized core contains more high-melting-point component atoms, while the later crystallized outer regions contain more low-melting-point component atoms. Typically, solid solution crystals grow in a dendritic manner, resulting in the dendrite arms containing more high-melting-point components and the interdendritic regions containing more low-melting-point component atoms. This leads to compositional inhomogeneity within the same grain.", "choice_question": "下列关于Dendritic segregation的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dendritic segregation occurs due to non-equilibrium cooling, resulting in composition gradients between dendrite cores (rich in high-melting-point components) and interdendritic regions (rich in low-melting-point components)", "B": "Dendritic segregation is a macroscopic phenomenon caused by temperature gradients during slow cooling, leading to layer-by-layer composition variations", "C": "Dendritic segregation primarily occurs in pure metals and is caused by vacancy diffusion during rapid solidification", "D": "Dendritic segregation results from equilibrium partitioning of solute atoms, creating uniform composition variations throughout the entire dendrite structure" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the microsegregation phenomenon under non-equilibrium conditions. Option B incorrectly describes it as macroscopic and layer-by-layer. Option C is wrong as it mentions pure metals and vacancy diffusion. Option D falsely attributes it to equilibrium conditions and uniform variations. The difficulty comes from distinguishing non-equilibrium microsegregation (correct) from macroscopic segregation (B), pure metal behavior (C), and equilibrium partitioning (D).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2412, "question": "At 700°C (973K), the enrichment rate of sulfur at the grain boundaries of iron is 7170. Estimate the bonding energy between sulfur atoms and iron (answer in kJ/mol and eV).", "answer": "Since the concentrations at the grain boundaries and within the grains are both much smaller than 1, the simplified formula for concentration segregation is used: -ΔG=8.314×973×ln7170=71.8 kJ/mol =71.8×10^3/(6.022×10^23×1.603×10^-19) eV=0.74 eV", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解硫原子与铁之间的键合能，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目需要进行多步计算（包括对数运算和单位转换），并需要理解浓度偏析的简化公式应用。虽然不涉及复杂的机理分析或创新设计，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解浓度偏析的简化公式，并进行多步计算（包括单位转换和对数运算）。虽然题目提供了关键公式，但需要正确应用热力学常数和单位换算，涉及中等应用层次的知识点。", "convertible": true, "correct_option": "71.8 kJ/mol and 0.74 eV", "choice_question": "At 700°C (973K), the enrichment rate of sulfur at the grain boundaries of iron is 7170. The bonding energy between sulfur atoms and iron is:", "conversion_reason": "The calculation question has a definite numerical answer, which can be converted into a multiple-choice format with the correct option derived from the provided solution.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "71.8 kJ/mol and 0.74 eV", "B": "35.9 kJ/mol and 0.37 eV", "C": "143.6 kJ/mol and 1.48 eV", "D": "179.5 kJ/mol and 1.86 eV" }, "correct_answer": "A", "explanation": "正确答案A基于McLean方程计算晶界偏聚能，考虑了温度与富集率的对数关系。干扰项B设计为数值减半，利用直觉上认为富集率与键能成反比的错误认知。干扰项C将数值翻倍，针对可能混淆Arrhenius方程指数关系的AI模型。干扰项D引入表面能数值(179.5 kJ/mol是铁的表面能)，制造专业直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2089, "question": "Calculate the relative amounts of pearlite, secondary cementite, and ledeburite in the microstructure of an iron-carbon alloy with a carbon content of w_c=0.04 after metastable cooling to room temperature.", "answer": "In the microstructure, the relative amount of P is 10.6%, the relative amount of Fe_3C_∥ is 3.10%, and the relative amount of L_d′ is 86.3%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算相对含量），答案给出了具体的百分比数值，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及铁碳合金相图中不同相的相对含量计算，需要理解相图的基本原理并应用杠杆定律进行计算。虽然计算过程较为直接，但需要综合运用多个知识点，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图的基本概念，掌握珠光体、二次渗碳体和莱氏体的形成条件，并能进行多步计算来求解相对含量。虽然题目给出了正确选项，但考生仍需具备综合分析能力才能正确选择。", "convertible": true, "correct_option": "In the microstructure, the relative amount of P is 10.6%, the relative amount of Fe_3C_∥ is 3.10%, and the relative amount of L_d′ is 86.3%.", "choice_question": "What are the relative amounts of pearlite, secondary cementite, and ledeburite in the microstructure of an iron-carbon alloy with a carbon content of w_c=0.04 after metastable cooling to room temperature?", "conversion_reason": "The answer is a specific and deterministic statement, which can be directly used as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pearlite: 10.6%, Secondary cementite: 3.10%, Ledeburite: 86.3%", "B": "Pearlite: 86.3%, Secondary cementite: 10.6%, Ledeburite: 3.10%", "C": "Pearlite: 3.10%, Secondary cementite: 86.3%, Ledeburite: 10.6%", "D": "Pearlite: 50%, Secondary cementite: 30%, Ledeburite: 20%" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately reflects the phase diagram calculations for this hypoeutectoid composition. Option B reverses the pearlite and ledeburite percentages, exploiting the common misconception about dominant phases. Option C completely inverts the phase distribution, targeting incorrect lever rule application. Option D presents arbitrary round numbers that may appeal to intuitive estimation but are scientifically incorrect.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1221, "question": "Materials with different crystal lattices have different slip systems, thus their tendency to deform also varies.", "answer": "~\\surd~", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性，答案以对错符号（~\\surd~）给出，符合判断题的特征 | 知识层次: 题目考查晶体结构和滑移系统的基本概念，属于基础概念的记忆和理解层次。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅要求识别晶体结构与变形倾向之间的基本关系，属于基础概念记忆层次，无需深入理解或分析多个概念。解题步骤简单，只需判断陈述的正确性。", "convertible": true, "correct_option": "~\\surd~", "choice_question": "Materials with different crystal lattices have different slip systems, thus their tendency to deform also varies.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture at room temperature due to their ionic/covalent bonding nature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature due to their bonding nature, some oxide ceramics like partially stabilized zirconia can exhibit transformation toughening and pseudo-ductile behavior. The use of 'all' makes this statement incorrect as there are exceptions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1464, "question": "What is a doped semiconductor?", "answer": "A semiconductor formed by intentionally adding a small amount of impurity elements to an intrinsic semiconductor is called a doped semiconductor. If the doping element is from Group VA in the periodic table, it forms an n-type semiconductor; if the doping element is from Group IIIA, it forms a p-type semiconductor.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对掺杂半导体进行定义和解释，答案提供了详细的文字描述和分类说明，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，包括掺杂半导体的定义和分类，以及n型和p型半导体的形成原理。这些内容属于材料科学中的基础知识点，不需要复杂的分析或综合应用。 | 难度: 在选择题中属于中等难度，题目要求考生理解并记忆掺杂半导体的基本定义和分类，包括n型和p型半导体的形成原理。虽然涉及多个概念，但都属于基础概念记忆范畴，不需要复杂的分析或比较。", "convertible": true, "correct_option": "A semiconductor formed by intentionally adding a small amount of impurity elements to an intrinsic semiconductor is called a doped semiconductor. If the doping element is from Group VA in the periodic table, it forms an n-type semiconductor; if the doping element is from Group IIIA, it forms a p-type semiconductor.", "choice_question": "Which of the following best describes a doped semiconductor?", "conversion_reason": "The answer is a standard definition and can be converted into a multiple-choice question format by providing the correct definition as one of the options and other plausible but incorrect definitions as the other options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A semiconductor with precisely controlled impurity concentrations that alter its charge carrier concentrations without changing its crystal structure", "B": "A semiconductor where foreign atoms replace lattice sites to create additional energy levels near the conduction or valence band edges", "C": "A semiconductor formed by alloying two different pure semiconductors to achieve intermediate bandgap properties", "D": "A semiconductor whose conductivity is enhanced by introducing defects through mechanical deformation rather than chemical impurities" }, "correct_answer": "B", "explanation": "Correct answer B describes the fundamental mechanism of doping where impurity atoms create donor/acceptor levels near band edges. Option A is incorrect because doping does change the electronic structure while maintaining crystal structure. Option C describes semiconductor alloys, not doping. Option D describes defect engineering, not chemical doping. Advanced AIs might choose A due to its technically accurate phrasing about carrier concentration, missing the key aspect of energy level modification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4317, "question": "Briefly describe the phenomenon of coring and why it occurs.", "answer": "Coring is the phenomenon whereby concentration gradients exist across grains in polycrystalline alloys, with higher concentrations of the component having the lower melting temperature at the grain boundaries. It occurs, during solidification, as a consequence of cooling rates that are too rapid to allow for the maintenance of the equilibrium composition of the solid phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述\"coring\"现象及其原因，需要文字解释和论述，答案也是以文字形式给出解释，符合简答题的特征。 | 知识层次: 题目考查对\"coring\"现象的基本定义和发生原因的理解，属于基础概念的记忆和解释，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生不仅记忆\"coring\"的基本定义，还需要理解其形成原因和机制。虽然不涉及多个概念的复杂比较，但需要解释现象背后的原理，属于概念解释和描述层次，比单纯的定义记忆要求更高。", "convertible": true, "correct_option": "Coring is the phenomenon whereby concentration gradients exist across grains in polycrystalline alloys, with higher concentrations of the component having the lower melting temperature at the grain boundaries. It occurs, during solidification, as a consequence of cooling rates that are too rapid to allow for the maintenance of the equilibrium composition of the solid phase.", "choice_question": "Which of the following best describes the phenomenon of coring and why it occurs?", "conversion_reason": "The answer is a standard definition and explanation of the phenomenon, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Coring is the phenomenon whereby concentration gradients exist across grains in polycrystalline alloys, with higher concentrations of the component having the lower melting temperature at the grain boundaries. It occurs, during solidification, as a consequence of cooling rates that are too rapid to allow for the maintenance of the equilibrium composition of the solid phase.", "B": "Coring is the formation of a hard, brittle phase at grain boundaries due to excessive cooling rates, which prevents uniform diffusion of alloying elements during solidification.", "C": "Coring refers to the preferential oxidation of certain alloy components at grain boundaries, creating concentration gradients when cooling rates exceed the critical threshold for equilibrium diffusion.", "D": "Coring is a defect caused by uneven thermal contraction during solidification, resulting in radial stress patterns that resemble tree rings in the microstructure." }, "correct_answer": "A", "explanation": "The correct answer A precisely describes coring as concentration gradients across grains due to non-equilibrium cooling. Option B incorrectly associates coring with hard phase formation, confusing it with precipitation hardening. Option C wrongly introduces oxidation as the mechanism, exploiting surface science confusion. Option D creates a visual analogy trap by describing thermal stresses instead of compositional variation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4818, "question": "It is known that the kinetics of recrystallization for some alloy obeys the Avrami equation, and that the value of n in the exponential is 5.0. If, at some temperature, the fraction recrystallized is 0.30 after 100 min, determine the rate of recrystallization at this temperature.", "answer": "the rate of recrystallization at this temperature is 8.76 × 10^{-3}, \\text{min}^{-1}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求根据给定的Avrami方程参数和条件，通过数值计算确定再结晶速率。解答过程涉及公式应用和具体数值计算，最终答案是一个具体的数值结果。 | 知识层次: 题目需要应用Avrami方程进行多步计算，涉及对公式的理解和变形，以及数值计算能力。虽然不涉及复杂的综合分析或机理解释，但需要将给定的参数代入方程并求解，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解Avrami方程的概念，并能正确应用方程进行多步骤计算。题目要求考生在已知n值和部分再结晶分数的情况下，计算再结晶速率，涉及对数运算和指数运算，计算过程较为复杂。虽然题目提供了正确选项，但解题过程需要较强的综合分析能力和数学运算能力。", "convertible": true, "correct_option": "8.76 × 10^{-3}, \text{min}^{-1}", "choice_question": "It is known that the kinetics of recrystallization for some alloy obeys the Avrami equation, and that the value of n in the exponential is 5.0. If, at some temperature, the fraction recrystallized is 0.30 after 100 min, what is the rate of recrystallization at this temperature?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.76 × 10^{-3} min^{-1}", "B": "1.20 × 10^{-2} min^{-1}", "C": "5.42 × 10^{-3} min^{-1}", "D": "3.67 × 10^{-3} min^{-1}" }, "correct_answer": "A", "explanation": "The correct answer is derived from the Avrami equation y = 1 - exp(-kt^n), where y=0.3, t=100 min, n=5. Solving gives k=8.76×10^{-3} min^{-1}. Option B is a common error from misapplying logarithmic transformations. Option C results from incorrectly assuming n=4. Option D comes from reversing the exponential term in the equation. Each incorrect option exploits a different mathematical or conceptual misunderstanding of the Avrami kinetics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 287, "question": "What are the characteristics of martensitic transformation?", "answer": "Martensitic transformation is a first-order nucleation and growth phase transformation in which substitutional atoms undergo diffusionless shear displacement (uniform or non-uniform), resulting in shape change and surface relief, and possesses the characteristics of invariant plane strain. Features: it has shear uniformity and regularity, no atomic diffusion occurs, the transformation speed is fast, the transformation occurs within a certain range, and there is a large shear-type elastic strain energy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释马氏体相变的特征，答案提供了详细的文字解释和论述，符合简答题的特点。 | 知识层次: 题目考查马氏体相变的基本特征和定义，属于基础概念的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及马氏体相变的多个特征，如无扩散、剪切均匀性、快速转变等，但这些都属于基础概念的解释和描述，不需要进行复杂的比较分析或深入的概念体系阐述。选择题型中，学生只需识别和记忆这些特征即可正确作答，因此难度等级为2。", "convertible": true, "correct_option": "Martensitic transformation is a first-order nucleation and growth phase transformation in which substitutional atoms undergo diffusionless shear displacement (uniform or non-uniform), resulting in shape change and surface relief, and possesses the characteristics of invariant plane strain. Features: it has shear uniformity and regularity, no atomic diffusion occurs, the transformation speed is fast, the transformation occurs within a certain range, and there is a large shear-type elastic strain energy.", "choice_question": "Which of the following best describes the characteristics of martensitic transformation?", "conversion_reason": "The answer is a standard description of a concept, which can be converted into a multiple-choice question format by presenting it as the correct option among several plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diffusionless shear displacement with invariant plane strain characteristics, occurring at speeds approaching the speed of sound", "B": "Second-order phase transformation involving gradual atomic rearrangement through vacancy diffusion", "C": "Isothermal transformation requiring sustained thermal activation energy input", "D": "Reconstructive transformation with complete breaking of atomic bonds and random reformation" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the key features of martensitic transformation including diffusionless mechanism, shear displacement, and invariant plane strain. Option B incorrectly describes it as second-order and diffusion-based, exploiting confusion with other phase transformations. Option C uses the isothermal characteristic which is typical for other transformations like bainite but not martensite. Option D describes reconstructive transformation which is fundamentally different from martensitic shear transformation, playing on the common confusion between these mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3633, "question": "Based on the zinc blende structure of BeO, determine the lattice parameter.", "answer": "The lattice parameter is 3.8567 Å.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求基于闪锌矿结构的BeO确定晶格参数，需要通过数值计算和公式应用得出具体数值（3.8567 Å），属于典型的计算题。 | 知识层次: 题目要求基于已知的锌矿结构计算晶格参数，属于基本公式应用和简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需直接应用锌矿结构的晶格参数公式进行计算，属于单一公式直接计算的简单应用。题目明确给出了正确选项，无需额外分析或组合多个公式，因此难度等级为1。", "convertible": true, "correct_option": "3.8567 Å", "choice_question": "Based on the zinc blende structure of BeO, what is the lattice parameter?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.8567 Å", "B": "4.3802 Å", "C": "3.8567 nm", "D": "4.3802 nm" }, "correct_answer": "A", "explanation": "The correct lattice parameter for BeO in zinc blende structure is 3.8567 Å. Option B uses the wurtzite structure parameter (4.3802 Å) to exploit structural confusion. Option C and D maintain correct numerical values but use nanometers instead of angstroms, targeting unit conversion errors. Advanced AIs may incorrectly select B due to overgeneralization from more common wurtzite structure data, or C/D due to unit oversight despite correct numerical recall.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1058, "question": "Interstitial phase", "answer": "Interstitial phase: A compound formed between non-metal atoms (X) and transition metal atoms, when the ratio of atomic radii of the metal element (M) to the non-metal element (X) $R_{\\\\mathrm{X}}/R_{\\\\mathrm{M}}<0.59$, the non-metal atoms are located in the interstices of the metal atoms and exhibit a relatively simple crystal structure, it is called an interstitial phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对“Interstitial phase”进行文字解释和论述，答案提供了详细的定义和特征描述，符合简答题的特点。 | 知识层次: 题目考查对间隙相（Interstitial phase）这一基本概念的定义和特征的理解，主要涉及原子半径比和晶体结构的简单描述，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但要求考生不仅要记住\"间隙相\"的定义，还需要理解原子半径比的条件（RX/RM<0.59）以及晶体结构特征。这超出了简单的定义记忆（等级1），需要对概念进行一定程度的解释和描述（等级2），但尚未达到需要阐述复杂概念体系的难度（等级3）。在选择题型中，这种题目需要考生能够识别和匹配概念定义中的关键要素。", "convertible": true, "correct_option": "Interstitial phase: A compound formed between non-metal atoms (X) and transition metal atoms, when the ratio of atomic radii of the metal element (M) to the non-metal element (X) $R_{\\mathrm{X}}/R_{\\mathrm{M}}<0.59$, the non-metal atoms are located in the interstices of the metal atoms and exhibit a relatively simple crystal structure, it is called an interstitial phase.", "choice_question": "下列关于Interstitial phase的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial phase: A compound formed between non-metal atoms (X) and transition metal atoms, when the ratio of atomic radii of the metal element (M) to the non-metal element (X) $R_{\\mathrm{X}}/R_{\\mathrm{M}}<0.59$, the non-metal atoms are located in the interstices of the metal atoms and exhibit a relatively simple crystal structure, it is called an interstitial phase.", "B": "Interstitial phase: A solid solution where solute atoms occupy the regular lattice sites of the solvent metal, forming a substitutional alloy with complex crystal structures.", "C": "Interstitial phase: A metastable compound formed when the atomic radius ratio $R_{\\mathrm{X}}/R_{\\mathrm{M}}>0.59$, where non-metal atoms distort the metal lattice to form complex interstitial structures.", "D": "Interstitial phase: A ceramic compound formed by ionic bonding between metal and non-metal atoms, where the non-metal atoms occupy tetrahedral or octahedral voids in the metal lattice." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines interstitial phases with the critical radius ratio condition and their characteristic simple crystal structures. Option B incorrectly describes substitutional alloys instead of interstitial compounds. Option C reverses the radius ratio condition and wrongly associates it with complex structures. Option D inaccurately describes ceramic ionic compounds rather than metallic interstitial phases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1772, "question": "11. The crystallographic characteristics of martensitic transformation are manifested as: _（27）_, etc.", "answer": "（27）strict orientation relationship", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（\"strict orientation relationship\"）来补充句子，这属于需要简短文字回答的简答题类型。 | 知识层次: 题目考查马氏体相变的晶体学特征，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆马氏体相变的晶体学特征之一（严格的取向关系），属于基础概念记忆层次，无需解释或分析，解题步骤简单直接。", "convertible": true, "correct_option": "strict orientation relationship", "choice_question": "The crystallographic characteristics of martensitic transformation are manifested as:", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "strict orientation relationship", "B": "random atomic rearrangement", "C": "isotropic lattice expansion", "D": "complete loss of crystallinity" }, "correct_answer": "A", "explanation": "The correct answer is A because martensitic transformation is a diffusionless process that maintains a strict crystallographic orientation relationship between parent and product phases. Option B exploits the common misconception that phase transformations always involve atomic diffusion. Option C traps those who confuse martensitic transformation with thermal expansion behavior. Option D targets the erroneous assumption that rapid transformations necessarily lead to amorphous structures, which is characteristic of glass formation rather than martensite.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2996, "question": "The three mechanical states of linear amorphous polymers are (1), (2), (3)", "answer": "(1) Glassy state; (2) High elastic state; (3) Viscous flow state", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写三个机械状态的名称，需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查对线性无定形聚合物三种力学状态的基本概念记忆，属于定义和分类的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆线性无定形聚合物的三个力学状态的基本名称，属于基础概念的直接回忆。题目不涉及解释、比较或分析，解题步骤简单直接，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "Glassy state; High elastic state; Viscous flow state", "choice_question": "The three mechanical states of linear amorphous polymers are:", "conversion_reason": "The answer is a standard set of terms, which can be presented as options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Glassy state; High elastic state; Viscous flow state", "B": "Crystalline state; Semi-crystalline state; Amorphous state", "C": "Elastic deformation; Plastic deformation; Viscoelastic deformation", "D": "Linear regime; Nonlinear regime; Fracture regime" }, "correct_answer": "A", "explanation": "The correct answer is A because these are the three distinct mechanical states of linear amorphous polymers as temperature increases. Option B confuses structural states with mechanical states. Option C lists deformation modes rather than thermodynamic states. Option D describes mechanical response regimes under stress, not inherent material states.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4842, "question": "Predict whether Nitrogen (N) will act as a donor or an acceptor when added to Silicon (Si). Assume that the impurity elements are substitutional.", "answer": "Nitrogen will act as a donor in Si. Since it (N) is from group VA of the periodic table, and an N atom has one more valence electron than an Si atom.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求通过文字解释和论述来预测氮在硅中的行为，并给出相应的理由，而不是从选项中选择、判断对错或进行数值计算。 | 知识层次: 题目考查对半导体掺杂基本原理的记忆和理解，涉及元素周期表中族属性和价电子数的基本概念，属于基础概念层次。 | 难度: 在选择题型中，该题目需要考生理解并应用基本的半导体掺杂原理，即通过比较氮（N）和硅（Si）的价电子数来判断氮在硅中的掺杂行为。虽然涉及基础概念记忆，但需要一定的解释和描述能力，属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "Nitrogen will act as a donor in Si.", "choice_question": "Predict whether Nitrogen (N) will act as a donor or an acceptor when added to Silicon (Si). Assume that the impurity elements are substitutional.", "conversion_reason": "The answer is a standard concept in semiconductor physics, and the question can be rephrased to fit a multiple-choice format by providing options for donor or acceptor behavior.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Donor (Nitrogen has one more valence electron than Silicon)", "B": "Acceptor (Nitrogen's smaller atomic radius creates strain that favors hole formation)", "C": "Neither (Nitrogen forms a neutral complex with silicon vacancies)", "D": "Amphoteric (Nitrogen can act as either depending on Fermi level position)" }, "correct_answer": "A", "explanation": "Nitrogen has 5 valence electrons compared to silicon's 4, making it a donor when substitutionally incorporated. Option B exploits the common misconception that strain effects can override electronic considerations. Option C appeals to the intuition about vacancy interactions but ignores the primary doping behavior. Option D uses a real phenomenon (amphoteric doping) but incorrectly applies it to nitrogen in silicon.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 503, "question": "How to overcome constitutional supercooling in single crystal growth?", "answer": "To overcome constitutional supercooling, increase the temperature gradient and reduce the growth rate R.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释如何克服单晶生长中的组成过冷现象，答案提供了文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要理解constitutional supercooling的概念，并应用温度梯度和生长速率的关系来解决问题，涉及多步分析和概念关联。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及单晶生长中的成分过冷问题，要求考生掌握温度梯度和生长速率对成分过冷的影响，并能综合分析这两个因素的相互作用。虽然不需要多步计算，但需要对概念有较深的理解和关联分析能力。", "convertible": true, "correct_option": "Increase the temperature gradient and reduce the growth rate R.", "choice_question": "How can constitutional supercooling be overcome in single crystal growth?", "conversion_reason": "The answer is a specific method or approach, which can be presented as a correct option among plausible distractors in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increase the temperature gradient and reduce the growth rate R", "B": "Decrease the temperature gradient and increase the growth rate R", "C": "Maintain constant temperature gradient while increasing impurity concentration", "D": "Use rapid quenching followed by annealing to eliminate solute segregation" }, "correct_answer": "A", "explanation": "The correct answer addresses the fundamental relationship G/R > mC0(1-k)/Dk where G is temperature gradient. Option B reverses the required conditions, exploiting common intuition errors about growth parameters. Option C introduces a plausible but incorrect impurity control strategy. Option D applies a valid metallurgical technique in the wrong context, creating a domain-specific knowledge trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2589, "question": "When the crystal around an edge dislocation contains excess interstitial atoms, how will the dislocation climb?", "answer": "Negative climb", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目需要解释边缘位错在含有过量间隙原子时的攀移行为，答案\"Negative climb\"是一个专业术语的解释，属于需要文字说明的简答题类型 | 知识层次: 题目涉及位错攀移的机理分析，需要理解间隙原子对位错运动的影响机制，并综合运用位错理论和扩散知识进行推理判断。这属于需要深入理解材料微观结构演变和缺陷行为的复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅要理解位错攀移的基本概念，还需要综合运用关于间隙原子对位错行为影响的知识，进行机理层面的推理分析。正确选项\"Negative climb\"需要考生能够将晶体缺陷理论与实际材料行为联系起来，这涉及到复杂现象的全面分析和机理解释能力。在选择题型中，这类需要多步骤推理和深度理解的题目属于最难的一类。", "convertible": true, "correct_option": "Negative climb", "choice_question": "When the crystal around an edge dislocation contains excess interstitial atoms, how will the dislocation climb?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Negative climb", "B": "Positive climb", "C": "No climb occurs", "D": "Random 3D motion" }, "correct_answer": "A", "explanation": "The correct answer is negative climb because excess interstitials create compressive stress, causing the dislocation to move away from the extra half-plane (negative climb). Option B is a common intuitive error as 'positive' seems logical for 'excess' atoms. Option C exploits confusion with perfect crystal behavior. Option D mimics thermal vibration effects which are irrelevant here.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 18, "question": "Calculate the packing coefficient in a face-centered cubic unit cell", "answer": "Atomic packing coefficient APC=(4×(4/3)πr^3)/(2√2r)^3=74.05%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算面心立方晶胞的堆积系数），答案给出了具体的计算公式和计算结果（74.05%），符合计算题的特征 | 知识层次: 题目要求应用基本公式（球体积公式和立方体体积公式）进行直接计算，并套用到面心立方晶胞的具体结构中。虽然需要理解晶胞结构和原子堆积的概念，但计算过程相对直接，属于基本公式应用和简单计算的范畴。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解面心立方晶胞的结构和原子堆积系数的概念，但解题步骤相对直接，只需套用给定的公式进行计算即可。不需要多个公式的组合或复杂的推导过程，因此难度等级为2。", "convertible": true, "correct_option": "74.05%", "choice_question": "What is the packing coefficient in a face-centered cubic unit cell?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "74.05%", "B": "68.02%", "C": "52.36%", "D": "81.45%" }, "correct_answer": "A", "explanation": "The correct answer is A (74.05%) because the face-centered cubic (FCC) unit cell has a packing efficiency of approximately 74%. Option B (68.02%) is designed to exploit the common confusion between FCC and body-centered cubic (BCC) packing coefficients. Option C (52.36%) targets the misconception of simple cubic packing efficiency. Option D (81.45%) is a high-value trap for those who might confuse FCC with hexagonal close-packed (HCP) structures, which have a slightly higher packing efficiency but are not the same as FCC.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1271, "question": "The solubility of substitutional solid solutions is related to atomic size factor, (4), electron concentration factor, and (5).", "answer": "4) electronegativity factor; (5) crystal structure factor", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写空缺部分的内容，需要根据知识进行文字解释和补充，而不是从选项中选择或进行数值计算。 | 知识层次: 题目考查对固溶体溶解度影响因素的基本概念记忆，包括原子尺寸因素、电负性因素、电子浓度因素和晶体结构因素等基础知识点，属于定义和分类的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然涉及基础概念记忆，但需要考生同时掌握原子尺寸因素、电子浓度因素、电负性因素和晶体结构因素四个相关概念，并正确匹配括号编号。这比单纯记忆单个定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。题目主要测试对固溶体溶解度影响因素的分类记忆能力，属于选择题中典型的\"多概念匹配\"类型。", "convertible": true, "correct_option": "electronegativity factor; crystal structure factor", "choice_question": "The solubility of substitutional solid solutions is related to atomic size factor, electron concentration factor, and which of the following factors?", "conversion_reason": "The original short answer question asks for specific factors related to the solubility of substitutional solid solutions. The answer consists of standard terms (electronegativity factor and crystal structure factor), which can be presented as options in a multiple-choice format. The question can be rephrased to fit a multiple-choice structure by asking which factors are related to the solubility.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "electronegativity factor", "B": "lattice vibration frequency", "C": "thermal expansion coefficient", "D": "surface energy anisotropy" }, "correct_answer": "A", "explanation": "The correct answer is A because electronegativity difference between solute and solvent atoms significantly affects solubility by influencing bond formation. Option B exploits the common misconception that vibrational properties directly govern solubility. Option C uses a real material property that correlates with bonding but isn't a fundamental solubility factor. Option D targets advanced AI's tendency to associate surface phenomena with bulk properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2534, "question": "Briefly describe the influence of atomic valence on solid solubility according to the Hume-Rothery rules", "answer": "The solid solubility of two elements is related to their atomic valence. The solubility of a high-valence element in a low-valence element is greater than that of a low-valence element in a high-valence element.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述原子价对固溶度的影响，答案以文字解释和论述的形式呈现，符合简答题的特征。 | 知识层次: 题目考查对Hume-Rothery规则中原子价对固溶度影响的基本概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及Hume-Rothery规则的基础概念记忆，但需要考生理解并描述原子价对固溶度的影响关系，而不仅仅是简单的定义记忆。正确选项要求考生能够解释两种不同价态元素之间的固溶度差异，这需要一定的概念理解和描述能力，但不需要复杂的分析或比较多个概念体系。", "convertible": true, "correct_option": "The solid solubility of two elements is related to their atomic valence. The solubility of a high-valence element in a low-valence element is greater than that of a low-valence element in a high-valence element.", "choice_question": "According to the Hume-Rothery rules, which of the following statements correctly describes the influence of atomic valence on solid solubility?", "conversion_reason": "The answer is a standard concept that can be rephrased into a multiple-choice format by presenting it as one of several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The solid solubility of two elements is related to their atomic valence. The solubility of a high-valence element in a low-valence element is greater than that of a low-valence element in a high-valence element.", "B": "Atomic valence has no significant effect on solid solubility, as it is primarily determined by atomic size and crystal structure factors.", "C": "The solubility is always higher when the solute has lower valence than the solvent, due to reduced electron cloud repulsion.", "D": "Valence difference promotes solid solubility by creating charge compensation effects that stabilize the crystal lattice." }, "correct_answer": "A", "explanation": "The correct answer A accurately reflects the Hume-Rothery rule regarding valence effects. Option B is a common misconception that ignores valence's role. Option C reverses the actual relationship and appeals to intuitive but incorrect electron repulsion arguments. Option D sounds plausible by invoking charge compensation but misrepresents the actual valence effect mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1665, "question": "Given carburization for 10 hours at 927°C, calculate the time t2 required to achieve the same carburization thickness at 870°C. Known values: D1=15.99×10^-12 m²/s, D2=7.94×10^-12 m²/s.", "answer": "According to D1/D2 = t2/t1, t2 = (D1/D2) t1 = (15.99×10^-12 / 7.94×10^-12) × 10 h = 2.014 × 10 h = 20.14 h", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及使用已知的扩散系数和时间来计算新的时间，答案也是具体的数值结果。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，即利用扩散系数与时间的关系公式进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解扩散系数与时间的关系公式（D1/D2 = t2/t1），但解题步骤直接且明确，仅需套用给定公式并进行简单数值计算即可得出答案。不需要多个公式组合或复杂分析，因此在选择题型内属于较低难度。", "convertible": true, "correct_option": "20.14 h", "choice_question": "Given carburization for 10 hours at 927°C, calculate the time t2 required to achieve the same carburization thickness at 870°C. Known values: D1=15.99×10^-12 m²/s, D2=7.94×10^-12 m²/s.", "conversion_reason": "The calculation yields a specific numerical answer, making it suitable for conversion into a multiple-choice question format where the correct option is clearly identifiable.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "20.14 h", "B": "10.07 h", "C": "40.28 h", "D": "5.04 h" }, "correct_answer": "A", "explanation": "The correct answer is derived from the relationship x^2 = Dt, where x is carburization thickness, D is diffusivity, and t is time. To achieve the same x at different temperatures, t2 = t1*(D1/D2) = 10*(15.99/7.94) = 20.14 h. Option B is half the correct value, exploiting the common error of not squaring the diffusivity ratio. Option C doubles the correct value, targeting those who invert the diffusivity ratio. Option D is one-fourth the correct value, combining both errors of inverting the ratio and missing the square relationship.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 540, "question": "9.Linear polymers can be reused, also known as (20); cross-linked polymers cannot be reused and are called thermosetting plastics.", "answer": "(20) Thermoplastic", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个术语（Thermoplastic）来补全句子，属于需要文字回答的简答题类型，而非从多个选项中选择或判断对错。 | 知识层次: 题目考查对线性聚合物和交联聚合物基本分类的记忆，以及热塑性和热固性塑料这两个基础概念的理解。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目直接考察对线性聚合物和交联聚合物的基本分类记忆，仅需识别\"Thermoplastic\"这一术语即可作答，无需进行概念解释或复杂分析。正确选项与题干中的关键提示词\"reused\"直接对应，属于最基础的概念记忆层次。", "convertible": true, "correct_option": "Thermoplastic", "choice_question": "Linear polymers can be reused, also known as:", "conversion_reason": "The short answer question asks for a standard term (Thermoplastic), which can be easily converted into a multiple-choice format by providing options including the correct term and plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermoplastic", "B": "Elastomer", "C": "Viscoelastic polymer", "D": "Thermosetting plastic" }, "correct_answer": "A", "explanation": "The correct answer is A because linear polymers that can be reused are classified as thermoplastics, which soften when heated and harden when cooled. Option B (Elastomer) is incorrect as it refers to polymers with elastic properties, not necessarily reusability. Option C (Viscoelastic polymer) is a distractor that describes a material property rather than reusability. Option D (Thermosetting plastic) is the opposite of the correct answer, as these polymers cannot be reused due to their cross-linked structure, creating a strong cognitive bias for those who misread the question.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4002, "question": "Does increasing strain rate favor brittle fracture in polymers?", "answer": "Yes, increasing strain rate favors brittle fracture in polymers.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性，答案直接给出了对错判断。 | 知识层次: 题目考查对聚合物应变率与脆性断裂关系的基本概念记忆和理解，属于基础概念层次。 | 难度: 该题目属于选择题型中的概念理解对错判断难度。虽然问题涉及聚合物材料的基本力学行为（应变速率与脆性断裂的关系），但只需理解\"应变速率增加会促进聚合物脆性断裂\"这一基本原理即可作答，不需要进行复杂的概念比较或分析。这属于对材料科学基础概念的简单应用层次，比纯粹的定义记忆（等级1）稍难，但明显低于需要综合分析多个概念的等级3难度。", "convertible": true, "correct_option": "Yes, increasing strain rate favors brittle fracture in polymers.", "choice_question": "Does increasing strain rate favor brittle fracture in polymers?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All polymers exhibit increased ductility when tested at cryogenic temperatures.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many polymers become more brittle at low temperatures, some specially designed polymers can maintain or even increase ductility due to unique molecular arrangements or secondary transitions. The use of 'all' makes this statement incorrect as it ignores these exceptions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4591, "question": "For aluminum, the heat capacity at constant volume Cv at 30 K is 0.81 J/mol-K, and the Debye temperature is 375 K. Estimate the specific heat at 50 K.", "answer": "the specific heat at 50 K is 139 J/kg-K.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的数据和公式进行数值计算，最终得出一个具体的数值结果（139 J/kg-K），这符合计算题的特征。 | 知识层次: 题目需要应用德拜模型和热容公式进行多步计算，涉及概念关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解德拜温度概念、热容与温度的关系，并进行多步计算。题目要求将摩尔热容转换为比热容，涉及单位换算和温度比例关系的应用，属于综合性计算问题。", "convertible": true, "correct_option": "139 J/kg-K", "choice_question": "For aluminum, the heat capacity at constant volume Cv at 30 K is 0.81 J/mol-K, and the Debye temperature is 375 K. Estimate the specific heat at 50 K.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "139 J/kg-K", "B": "0.97 J/mol-K", "C": "1.35 J/g-K", "D": "215 J/kg-K" }, "correct_answer": "A", "explanation": "The correct answer is A (139 J/kg-K) calculated using the Debye model scaling from the given 30K data point. Option B (0.97 J/mol-K) is a plausible but incorrect molar heat capacity value that might result from misapplying the temperature scaling. Option C (1.35 J/g-K) uses incorrect units that could trap those not paying attention to unit conversions. Option D (215 J/kg-K) represents an overestimation that might occur if incorrectly assuming linear temperature dependence beyond the Debye temperature.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3678, "question": "Determine the ASTM grain size number if 25 grains/square inch are observed at a magnification of 50 .", "answer": "the astm grain size number is n = 3.6", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定ASTM晶粒度数，答案是一个具体的数值结果（n = 3.6），这表明解答过程涉及计算步骤。 | 知识层次: 题目要求应用ASTM晶粒度计算公式进行简单计算，属于基本公式的直接套用，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用ASTM grain size number的计算公式，但题目已经提供了所有必要的数据（25 grains/square inch和50倍放大倍数），只需直接套用公式即可得出结果。解题步骤相对简单，不需要复杂的推导或多步骤计算，因此属于等级2难度。", "convertible": true, "correct_option": "n = 3.6", "choice_question": "Determine the ASTM grain size number if 25 grains/square inch are observed at a magnification of 50.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.6", "B": "4.2", "C": "2.9", "D": "5.0" }, "correct_answer": "A", "explanation": "正确答案A(3.6)是通过ASTM E112标准公式N=2^(n-1)计算得出，其中N为实际放大倍数下的晶粒数(25×(50/100)^2=6.25)。干扰项B(4.2)利用了对数计算时的常见舍入误差陷阱；C(2.9)设计为忽略放大倍数校正的直觉错误；D(5.0)则是基于错误假设所有晶粒都完整显示在视野中的过估值。这些干扰项都利用了材料科学中晶粒度计算时最易混淆的关键点。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 717, "question": "The two most closely packed arrangements of equal-sized spheres", "answer": "There are mainly cubic closest packing and hexagonal closest packing; the cubic closest packing arrangement has the close-packed planes arranged in the sequence ABCABC..., while the hexagonal closest packing arrangement has the close-packed planes arranged in the sequence ABAB...", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两种最紧密排列的等径球体排列方式，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目考查对等径球最密堆积排列方式的基础概念记忆和理解，包括立方最密堆积和六方最密堆积的定义及其堆垛序列。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生区分两种紧密堆积方式（立方最密堆积和六方最密堆积）的排列序列（ABCABC...和ABAB...）。这要求考生不仅记住定义，还需要理解并描述两种堆积方式的差异，属于概念解释和描述的层次。", "convertible": true, "correct_option": "There are mainly cubic closest packing and hexagonal closest packing; the cubic closest packing arrangement has the close-packed planes arranged in the sequence ABCABC..., while the hexagonal closest packing arrangement has the close-packed planes arranged in the sequence ABAB...", "choice_question": "Which of the following describes the two most closely packed arrangements of equal-sized spheres?", "conversion_reason": "The answer is a standard description of the two most closely packed arrangements of equal-sized spheres, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cubic closest packing (ABCABC...) and hexagonal closest packing (ABAB...) with identical packing density of 74%", "B": "Body-centered cubic (68%) and face-centered cubic (74%) arrangements", "C": "Simple hexagonal (60%) and rhombohedral (70%) packing sequences", "D": "Tetragonal (63%) and orthorhombic (65%) packing configurations" }, "correct_answer": "A", "explanation": "The correct answer is A because cubic closest packing (CCP) and hexagonal closest packing (HCP) are indeed the two most efficient packing arrangements for equal-sized spheres, both achieving 74% packing efficiency. Option B is incorrect because while FCC is correct, BCC is not one of the two most closely packed arrangements. Option C uses real but less efficient packing structures to create confusion. Option D introduces lower-symmetry crystal systems that don't represent maximum packing efficiency, exploiting the tendency to consider all crystal systems equally.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 118, "question": "Chemical analysis of pyrite yields two possible compositions based on the Fe/S ratio from the analytical data: Fe1-xS and FeS1-x. The former implies a defect structure with Fe vacancies, while the latter indicates Fe substitution. How can experimental methods determine whether the mineral belongs to Fe1-xS (Fe vacancy defect structure)?", "answer": "Fe1-xS contains Fe vacancies and is a non-stoichiometric compound, exhibiting h'P-type semiconductor properties. By measuring its semiconductor characteristics, if the results show h'P-type semiconductor behavior, it can be confirmed that the mineral composition is Fe1-xS.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求通过实验方法确定矿物属于Fe1-xS结构，需要文字解释和论述半导体特性的测量方法及其与矿物结构的关系。答案提供了详细的解释和论述，符合简答题的特征。 | 知识层次: 题目要求通过实验方法确定矿物属于Fe1-xS结构，涉及非化学计量化合物的缺陷结构分析、半导体特性测量以及结果解释。这需要综合运用材料科学中的缺陷化学、半导体物理等知识，进行推理分析和机理解释，属于较高层次的认知能力要求。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解非化学计量化合物的概念（Fe1-xS和FeS1-x的区别），还需要掌握半导体特性与缺陷结构之间的机理关系。正确选项涉及通过实验现象（h'P型半导体行为）反推晶体缺陷类型，这需要考生具备：", "convertible": true, "correct_option": "Fe1-xS contains Fe vacancies and is a non-stoichiometric compound, exhibiting h'P-type semiconductor properties. By measuring its semiconductor characteristics, if the results show h'P-type semiconductor behavior, it can be confirmed that the mineral composition is Fe1-xS.", "choice_question": "Chemical analysis of pyrite yields two possible compositions based on the Fe/S ratio from the analytical data: Fe1-xS and FeS1-x. The former implies a defect structure with Fe vacancies, while the latter indicates Fe substitution. How can experimental methods determine whether the mineral belongs to Fe1-xS (Fe vacancy defect structure)?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hall effect measurements showing p-type conductivity", "B": "X-ray diffraction revealing expanded lattice parameters", "C": "Mössbauer spectroscopy detecting Fe3+ species", "D": "Thermogravimetric analysis showing sulfur loss" }, "correct_answer": "A", "explanation": "The correct answer is A because Fe1-xS with Fe vacancies creates hole carriers, exhibiting p-type semiconductor behavior detectable by Hall effect. Option B is a cognitive bias trap - while lattice expansion occurs in both defect types, it's not definitive. Option C exploits professional intuition - Fe3+ presence could suggest either defect type. Option D is a multi-level verification trap - sulfur loss occurs in both cases but doesn't distinguish vacancy mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 346, "question": "(Taking the face-centered cubic unit cell as an example) What are the common parameters used to describe the characteristics of a crystal structure (unit cell)? What is the close-packed plane of an FCC unit cell?", "answer": "Close-packed plane {111}.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求描述晶体结构的常见参数和FCC晶胞的密排面，需要文字解释和论述，答案也是以文字形式给出。 | 知识层次: 题目考查晶体结构的基本参数和密排面的记忆，属于基础概念的记忆和理解层面，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆并识别面心立方晶胞的密排面{111}，属于基础概念记忆层次，无需复杂分析或推理步骤。", "convertible": true, "correct_option": "{111}", "choice_question": "What is the close-packed plane of an FCC unit cell?", "conversion_reason": "The answer is a standard term ({111}) which can be directly used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by focusing on the close-packed plane of an FCC unit cell.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "{111}", "B": "{110}", "C": "{100}", "D": "{112}" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC crystal structures, the {111} planes are the close-packed planes with the highest atomic density. Option B ({110}) is a common trap as these planes have high atomic density but are not the closest packed. Option C ({100}) exploits the visual symmetry bias where these planes appear prominently in unit cell diagrams. Option D ({112}) is a subtle trap using a plane that appears in twinning systems but is not close-packed.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2859, "question": "The tensile strength of brittle materials can be expressed by the following formula: \\n\\n$$\\n\\\\sigma_{\\\\mathrm{m}}=2\\\\sigma_{\\\\mathrm{0}}\\\\bigg(\\\\frac{\\\\ell}{r}\\\\bigg)^{\\\\frac{1}{2}}\\n$$\\n\\nWhere, $\\\\sigma_{0}$ is the nominal applied tensile stress; $l$ is the length of the surface crack or half the length of an internal crack; $r$ is the radius of curvature at the crack tip; and $\\\\sigma_{\\\\infty}$ is actually the maximum stress caused by stress concentration at the crack tip. Now assume that the critical length of the surface crack in $\\\\mathrm{Al}_{2}\\\\mathrm{O}_{3}$ ceramic is $l = 2\\\\times10^{-3}\\\\mathrm{mm}$, its theoretical fracture strength is $\\\\frac{E}{10}$, where $E$ is the elastic modulus of the material and is $393\\\\mathrm{GPa}$. Calculate: When a tensile stress of $275\\\\mathrm{MPa}$ is applied to the $\\\\mathrm{Al}_{2}\\\\mathrm{O}_{3}$ ceramic specimen, what is the critical radius of curvature $r_{\\\\mathfrak{c}}$ at the crack tip that causes fracture?", "answer": "When the tensile stress reaches the fracture strength of the material ($\\\\frac{E}{10}$), $\\\\mathrm{Al}_{2}\\\\mathrm{O}_{3}$ fractures, therefore:\\n\\n$$\\n\\\\frac{E}{10}=2\\\\sigma_{\\\\circ}\\\\left(\\\\frac{\\\\lambda}{r}\\\\right)^{\\\\frac{1}{2}}\\\\Rightarrow r=\\\\frac{400\\\\ l\\\\sigma_{0}^{2}}{E^{2}}\\n$$\\n\\n$$\\nr_{\\\\mathrm{c}}={\\\\frac{400l\\\\sigma_{0}^{2}}{E^{2}}}={\\\\frac{400\\\\times2\\\\times10^{-3}\\\\times(275)^{2}}{(393\\\\times10^{3})^{2}}}=3.9\\\\times10^{-7}(\\\\mathrm{mm})=0.39(\\\\mathrm{nm})\\n$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出一个具体的数值结果（临界半径）。解答过程涉及公式推导和数值代入计算，符合计算题的特征。 | 知识层次: 题目需要应用给定的公式进行多步计算，涉及材料断裂强度的理论计算和实际应用，需要理解公式中各参数的含义及其相互关系，并进行数值计算。虽然不涉及复杂的综合分析或创新应用，但超出了简单直接套用公式的层次。 | 难度: 在选择题中属于中等偏上难度，需要理解断裂力学公式的含义，并正确代入多个变量进行计算。题目涉及弹性模量、临界裂纹长度和临界半径等概念的综合运用，解题步骤包括公式变形和单位换算，计算过程较为复杂但步骤明确。虽然题目提供了关键公式，但需要考生具备较强的综合分析能力和计算技巧。", "convertible": true, "correct_option": "0.39 nm", "choice_question": "The tensile strength of brittle materials can be expressed by the following formula: \n\n$$\n\\sigma_{\\mathrm{m}}=2\\sigma_{\\mathrm{0}}\\bigg(\\frac{\\ell}{r}\\bigg)^{\\frac{1}{2}}\n$$\n\nWhere, $\\sigma_{0}$ is the nominal applied tensile stress; $l$ is the length of the surface crack or half the length of an internal crack; $r$ is the radius of curvature at the crack tip; and $\\sigma_{\\infty}$ is actually the maximum stress caused by stress concentration at the crack tip. Now assume that the critical length of the surface crack in $\\mathrm{Al}_{2}\\mathrm{O}_{3}$ ceramic is $l = 2\\times10^{-3}\\mathrm{mm}$, its theoretical fracture strength is $\\frac{E}{10}$, where $E$ is the elastic modulus of the material and is $393\\mathrm{GPa}$. When a tensile stress of $275\\mathrm{MPa}$ is applied to the $\\mathrm{Al}_{2}\\mathrm{O}_{3}$ ceramic specimen, what is the critical radius of curvature $r_{\\mathfrak{c}}$ at the crack tip that causes fracture?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.39 nm", "B": "1.23 nm", "C": "2.45 nm", "D": "3.14 nm" }, "correct_answer": "A", "explanation": "The correct answer is calculated by substituting the given values into the formula: σ_m = E/10 = 39.3 GPa, σ_0 = 275 MPa, l = 2×10^-3 mm. Solving for r gives 0.39 nm. Option B is designed to exploit confusion between surface and internal crack lengths. Option C uses an incorrect assumption that the elastic modulus should be divided by π instead of 10. Option D is derived from mistakenly using the yield strength formula instead of fracture strength.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 46, "question": "What is the basis for the classification of silicate crystals?", "answer": "Silicate crystals are mainly classified based on the arrangement and bonding manner of [Si04] in the structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释硅酸盐晶体的分类基础，答案需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对硅酸盐晶体分类基础概念的记忆和理解，主要涉及硅氧四面体[Si04]在结构中的排列和键合方式这一基本原理。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别硅酸盐晶体分类的基本依据，即[Si04]的排列和键合方式。这属于基础概念记忆层次，无需复杂推理或分析，解题步骤简单直接。", "convertible": true, "correct_option": "Silicate crystals are mainly classified based on the arrangement and bonding manner of [Si04] in the structure.", "choice_question": "What is the basis for the classification of silicate crystals?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The degree of polymerization of [SiO4] tetrahedra", "B": "The ratio of silicon to oxygen atoms in the unit cell", "C": "The coordination number of silicon atoms", "D": "The presence of non-silicate anions in the structure" }, "correct_answer": "A", "explanation": "The correct answer is A because silicate classification is fundamentally based on how [SiO4] tetrahedra polymerize (isolated, chains, sheets, frameworks). Option B exploits the intuitive but incorrect assumption that stoichiometry determines classification. Option C uses the fact that silicon always has coordination number 4 in silicates, making it seem plausible but irrelevant. Option D introduces a red herring by suggesting non-silicate components affect the classification, which is a secondary consideration at best.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1287, "question": "After cold deformation, the control of grain size after recrystallization is related to the degree of cold deformation, original grain size, recrystallization temperature, and impurities, among others. Among these, what is (21)?", "answer": "Degree of cold deformation", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释或论述影响再结晶晶粒尺寸的因素，并具体指出其中一个因素（冷变形程度）。虽然答案是一个具体的因素，但题目本身更倾向于简答形式，需要理解并解释多个因素之间的关系。 | 知识层次: 题目考查对冷变形后晶粒尺寸控制因素的基础概念记忆，仅需识别关键影响因素之一（冷变形程度），无需深入分析或综合应用。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别冷变形程度这一单一因素即可作答。题目直接给出了明确的关键词\"degree of cold deformation\"，不需要进行概念比较或复杂推理，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Degree of cold deformation", "choice_question": "After cold deformation, the control of grain size after recrystallization is related to several factors. Among these, which one is the most significant?", "conversion_reason": "The original question is a short answer question asking for a specific factor among several mentioned. The answer is a standard term ('Degree of cold deformation'), making it suitable for conversion to a multiple-choice format. The question can be rephrased to fit the multiple-choice format by asking which factor is the most significant among the listed ones.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Degree of cold deformation", "B": "Original grain size before deformation", "C": "Recrystallization temperature", "D": "Presence of trace impurities" }, "correct_answer": "A", "explanation": "The degree of cold deformation is the most significant factor because it directly determines the stored energy and dislocation density, which drive recrystallization and control the final grain size. Option B is a cognitive bias trap - while original grain size affects deformation uniformity, it's not the primary determinant of recrystallized grain size. Option C exploits professional intuition - temperature affects kinetics but not the fundamental size-determining mechanism. Option D is a multi-level verification trap - while impurities can pin boundaries, their effect is secondary compared to deformation strain energy in most metallic systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 338, "question": "What is the main difference between crystallization and solid-state phase transformation?", "answer": "Crystallization is the process of forming crystals from amorphous liquid, gas, or solid non-crystalline states; solid-state phase transformation is the structural change between solid/solid phases. The driving forces for both processes are the chemical free energy difference.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两个概念之间的主要区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对结晶和固态相变这两个基本概念的定义和区别的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题中属于中等难度，题目要求考生理解并区分两个相关但不同的概念（结晶和固态相变），并正确识别它们的定义和驱动力的共同点。虽然涉及基础概念记忆，但需要一定的概念解释和描述能力，而不仅仅是简单的定义复述。", "convertible": true, "correct_option": "Crystallization is the process of forming crystals from amorphous liquid, gas, or solid non-crystalline states; solid-state phase transformation is the structural change between solid/solid phases. The driving forces for both processes are the chemical free energy difference.", "choice_question": "What is the main difference between crystallization and solid-state phase transformation?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystallization involves long-range atomic diffusion while solid-state transformation occurs through local atomic rearrangement", "B": "Crystallization requires nucleation sites but solid-state transformations are homogeneous throughout the material", "C": "Crystallization is exothermic while solid-state phase transformations are always endothermic", "D": "Crystallization changes the chemical composition but solid-state transformations preserve it" }, "correct_answer": "D", "explanation": "The correct answer is D because crystallization fundamentally forms crystals from non-crystalline states without altering chemical composition, while solid-state transformations only rearrange existing atoms. Option A reverses the typical diffusion characteristics. Option B is incorrect because both processes can be heterogeneous. Option C is wrong as both processes can be exothermic or endothermic depending on specific systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 939, "question": "Analyze the causes of primary banded structure formation.", "answer": "The formation of primary banded structure is related to dendrite formation during solidification and the hot rolling process, where the dark bands are dendrite trunks (with fewer solutes) and the white bands are interdendritic regions enriched with impurities.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析带状结构形成的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析初级带状结构形成的原因，涉及凝固过程中的枝晶形成和热轧工艺的综合分析，需要理解枝晶主干和枝晶间区域的成分差异及其对结构形成的影响。这需要综合运用材料科学知识，进行推理分析和机理解释，属于较高层次的认知能力要求。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The formation of primary banded structure is related to dendrite formation during solidification and the hot rolling process, where the dark bands are dendrite trunks (with fewer solutes) and the white bands are interdendritic regions enriched with impurities.", "choice_question": "Which of the following best describes the causes of primary banded structure formation?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The formation of primary banded structure is related to dendrite formation during solidification and the hot rolling process, where the dark bands are dendrite trunks (with fewer solutes) and the white bands are interdendritic regions enriched with impurities.", "B": "Primary banded structures result from alternating layers of ferrite and pearlite formed during isothermal annealing, with the spacing determined by the cooling rate.", "C": "The banding occurs due to preferential diffusion of carbon atoms along specific crystallographic planes during normalizing heat treatment.", "D": "Banded structures originate from periodic variations in dislocation density caused by cyclic loading during mechanical processing." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the dendrite-related mechanism of primary banding during solidification and hot rolling. Option B incorrectly associates banding with ferrite-pearlite formation during annealing. Option C misattributes the phenomenon to carbon diffusion during normalizing. Option D falsely links banding to dislocation patterning from cyclic loading. Options B-D exploit common misconceptions about microstructural banding mechanisms in materials processing.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4462, "question": "Explain why residual thermal stresses are introduced into a glass piece when it is cooled.", "answer": "Residual thermal stresses are introduced into a glass piece when it is cooled because surface and interior regions cool at different rates, and, therefore, contract different amounts; since the material will experience very little, if any deformation, stresses are established.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释玻璃冷却过程中残余热应力的产生原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释残余热应力在玻璃冷却过程中的产生机理，涉及不同冷却速率导致的收缩差异和应力建立，需要综合运用热力学和材料科学知识进行推理分析，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅理解残余热应力的基本概念，还需要掌握玻璃冷却过程中表面和内部区域冷却速率差异导致的收缩量不同这一机理。正确选项涉及对复杂现象的深度解释（冷却速率差异、收缩量差异、应力产生机制），需要考生具备综合分析和推理能力。这种题目在选择题中属于需要机理深度解释的类型，比单纯记忆或简单应用类题目难度更高。", "convertible": true, "correct_option": "Residual thermal stresses are introduced into a glass piece when it is cooled because surface and interior regions cool at different rates, and, therefore, contract different amounts; since the material will experience very little, if any deformation, stresses are established.", "choice_question": "Why are residual thermal stresses introduced into a glass piece when it is cooled?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Due to differential cooling rates between surface and interior regions causing non-uniform contraction", "B": "Because the glass transition temperature causes sudden volume expansion during cooling", "C": "As a result of crystallization-induced phase transformation stresses during cooling", "D": "Owing to the Poisson's ratio effect creating shear stresses during thermal contraction" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the actual mechanism where surface cools faster than interior, creating non-uniform contraction. Option B exploits cognitive bias by incorrectly attributing to glass transition temperature (which doesn't cause expansion). Option C uses professional intuition trap by referencing real but irrelevant crystallization effects (glass is amorphous). Option D employs multi-level verification trap with valid material property (Poisson's ratio) misapplied to thermal stress context.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2356, "question": "Why do commercial oxides such as windows and beverage glass require the addition of CaO to SiO2?", "answer": "CaO cannot form a network in glass. Calcium ions have only one functionality, and Ca2+ has only two functionalities. When they are added to the SiO2 network and connected with oxygen ions, they inevitably break a primary bond of the network, reducing the density of primary bonds in the network and thereby lowering the glass transition temperature. For general wide-mouth bottles and window glass, which are used at low temperatures, they do not require an excessively high glass transition temperature Tg. A low Tg makes the product easier to handle and reduces costs.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么商业氧化物如窗户和饮料玻璃需要添加CaO到SiO2中，答案提供了详细的文字解释和论述，没有涉及选择题、判断题或计算题的特征。 | 知识层次: 题目要求解释CaO在商业氧化物玻璃中的作用机制，涉及网络形成体与非网络形成体的概念、玻璃结构的变化、玻璃转变温度的影响因素等多方面的知识。需要综合运用材料科学中的玻璃结构理论，进行推理分析，解释添加CaO如何降低玻璃的Tg，并联系实际应用需求。这超出了简单记忆或基本应用的层次，属于对知识的深度理解和综合分析。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解CaO和SiO2在玻璃网络结构中的基本作用，还需要深入分析钙离子的功能性和对玻璃网络结构的影响机制。正确选项涉及复杂的网络结构破坏机理、玻璃转变温度的影响因素以及实际应用中的工程考量。这种题目需要考生具备综合运用材料科学知识、进行推理分析和机理解释的能力，远超简单的概念记忆或单一知识点应用。在选择题型内，此类需要多维度分析和深度理解的题目属于最复杂的类型。", "convertible": true, "correct_option": "CaO cannot form a network in glass. Calcium ions have only one functionality, and Ca2+ has only two functionalities. When they are added to the SiO2 network and connected with oxygen ions, they inevitably break a primary bond of the network, reducing the density of primary bonds in the network and thereby lowering the glass transition temperature. For general wide-mouth bottles and window glass, which are used at low temperatures, they do not require an excessively high glass transition temperature Tg. A low Tg makes the product easier to handle and reduces costs.", "choice_question": "Why do commercial oxides such as windows and beverage glass require the addition of CaO to SiO2?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be kept as is, and the answer can be one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ca2+ ions break the SiO2 network structure, reducing bond density and lowering Tg for easier processing", "B": "CaO increases the refractive index to improve optical clarity in window glass", "C": "Calcium ions enhance the glass network connectivity by forming additional Si-O-Ca bonds", "D": "CaO acts as a flux to completely dissolve the silica network at lower temperatures" }, "correct_answer": "A", "explanation": "Correct answer A explains how Ca2+ ions with only two functionalities break the continuous SiO2 network, reducing primary bond density and lowering Tg for practical processing. Option B exploits optical property misconception (refractive index is mainly determined by SiO2). Option C reverses the actual effect by suggesting network enhancement (common AI error). Option D misrepresents the flux mechanism (CaO modifies rather than dissolves the network).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1385, "question": "Critical deformation degree", "answer": "Critical deformation degree is the minimum pre-cold deformation required for metal to undergo recrystallization at a given temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Critical deformation degree\"这一概念进行文字解释和论述，答案提供了详细的定义说明，符合简答题的特征。 | 知识层次: 题目考查对\"临界变形度\"这一基础概念的定义记忆和理解，属于材料科学中金属再结晶的基本原理范畴，不涉及应用或分析过程。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确理解并描述“Critical deformation degree”的定义及其在金属再结晶中的作用。这比简单的定义记忆（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Critical deformation degree is the minimum pre-cold deformation required for metal to undergo recrystallization at a given temperature.", "choice_question": "Which of the following best defines 'Critical deformation degree'?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct definition among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The minimum pre-cold deformation required for metal to undergo recrystallization at a given temperature", "B": "The maximum strain a material can withstand before fracture during hot working", "C": "The deformation threshold where dislocation density reaches saturation in a single crystal", "D": "The critical strain required to initiate dynamic recrystallization during deformation" }, "correct_answer": "A", "explanation": "The correct answer is A because critical deformation degree specifically refers to the minimum cold deformation needed for subsequent recrystallization. Option B is a cognitive bias trap, confusing it with hot working fracture strain. Option C exploits professional intuition by referencing dislocation saturation, which is related but distinct. Option D is a multi-level verification trap, mixing up static and dynamic recrystallization conditions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4455, "question": "For refractory ceramic materials, cite three characteristics that improve with increasing porosity.", "answer": "For refractory ceramic materials, three characteristics that improve with increasing porosity are (1) decreased thermal expansion and contraction upon thermal cycling, (2) improved thermal insulation, and (3) improved resistance to thermal shock.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举并解释三个特性，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对耐火陶瓷材料特性的基本记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列举三个特性，但这些都是与多孔耐火陶瓷材料相关的基础概念，属于记忆性知识。考生需要理解并记住这些特性，但不需要进行复杂的分析或推理。因此，难度等级为2。", "convertible": true, "correct_option": "decreased thermal expansion and contraction upon thermal cycling, improved thermal insulation, and improved resistance to thermal shock", "choice_question": "Which of the following are characteristics of refractory ceramic materials that improve with increasing porosity?", "conversion_reason": "The answer is a list of standard characteristics that can be presented as options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Decreased thermal expansion and contraction upon thermal cycling", "B": "Increased elastic modulus at elevated temperatures", "C": "Enhanced ionic conductivity through grain boundaries", "D": "Improved fracture toughness under compressive loads" }, "correct_answer": "A", "explanation": "Correct answer A is valid because porosity reduces thermal expansion mismatch stresses during cycling. Option B exploits the common misconception that porosity always decreases stiffness - while true at room temperature, the relationship reverses in refractory ceramics at high temperatures due to pore collapse. Option C uses a real phenomenon (ionic conduction) but incorrectly applies it to refractory ceramics where electronic conduction dominates. Option D creates confusion by mixing compressive strength (which does improve with porosity) with fracture toughness (which decreases).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 185, "question": "At high temperature, a metal is melted on an Al2O3 plate. If the liquid surface energy is only half of the Al2O3 surface energy, while the interfacial energy is twice the Al2O3 surface tension, estimate the size of the contact angle?", "answer": "Substituting the known data into the Young's equation, cosθ=(0.5−1)/0.5=−1, the contact angle can be calculated to be approximately 180 degrees.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用（使用Young's方程计算接触角），答案给出了具体的计算过程和结果（180度）。 | 知识层次: 题目主要涉及Young's方程的直接应用和简单的数值计算，不需要多步推理或综合分析，属于基本公式的直接套用。 | 难度: 在选择题型内，该题目属于单一公式直接计算的难度等级。题目直接给出了所有必要的数据，只需将已知数值代入Young's方程（cosθ=(γSV - γSL)/γLV）即可得出结果。解题步骤简单明了，无需额外的概念理解或复杂的计算过程，符合等级1的定义。", "convertible": true, "correct_option": "180 degrees", "choice_question": "At high temperature, a metal is melted on an Al2O3 plate. If the liquid surface energy is only half of the Al2O3 surface energy, while the interfacial energy is twice the Al2O3 surface tension, what is the size of the contact angle?", "conversion_reason": "The calculation yields a specific numerical answer (180 degrees), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "180 degrees", "B": "120 degrees", "C": "90 degrees", "D": "60 degrees" }, "correct_answer": "A", "explanation": "The correct answer is 180 degrees because when the interfacial energy (2γ_Al2O3) equals the sum of the liquid surface energy (0.5γ_Al2O3) and Al2O3 surface energy (γ_Al2O3), the contact angle reaches its maximum value indicating complete non-wetting. Option B (120 degrees) exploits the common misconception that high angles cluster around 120 degrees in ceramic systems. Option C (90 degrees) targets the intuitive but incorrect assumption of equilibrium at right angles. Option D (60 degrees) is designed to trap those who mistakenly apply Young's equation without proper parameter substitution.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4574, "question": "At room temperature the electrical conductivity of \\mathrm{PbTe} is 500(\\Omega·m)^{-1}, whereas the electron and hole mobilities are 0.16 and 0.075{m}^{2} / V·s, respectively. Compute the intrinsic carrier concentration for \\mathrm{PbTe} at room temperature.", "answer": "the intrinsic carrier concentration for \\mathrm{pbte} at room temperature is 1.33 × 10^{22}{m}^{-3}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（电导率、载流子迁移率与载流子浓度的关系）来求解本征载流子浓度，答案是一个具体的数值结果。 | 知识层次: 题目主要考查基本公式的应用和简单计算，即通过给定的电导率、电子和空穴迁移率来计算本征载流子浓度。虽然需要理解相关概念，但计算过程直接且无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，需要学生掌握基本的电导率与载流子浓度关系公式（σ = n·e·(μ_e + μ_h)），并进行简单的代数运算来求解本征载流子浓度。虽然涉及物理概念的理解，但计算步骤直接且无需复杂推导，属于选择题中中等偏下的难度。", "convertible": true, "correct_option": "1.33 × 10^{22} m^{-3}", "choice_question": "At room temperature the electrical conductivity of PbTe is 500 (Ω·m)^{-1}, whereas the electron and hole mobilities are 0.16 and 0.075 m^{2}/V·s, respectively. What is the intrinsic carrier concentration for PbTe at room temperature?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.33 × 10^{22} m^{-3}", "B": "2.66 × 10^{22} m^{-3}", "C": "6.65 × 10^{21} m^{-3}", "D": "3.99 × 10^{22} m^{-3}" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula σ = n_i * e * (μ_e + μ_h), where σ is conductivity, n_i is intrinsic carrier concentration, e is electron charge, and μ_e/μ_h are mobilities. Option B doubles the correct value by incorrectly assuming equal contributions from electrons and holes. Option C is half the correct value due to a sign error in mobility summation. Option D triples the correct value by misapplying the mobility ratio.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1625, "question": "What is the driving force for nucleation in solid-state phase transformations?", "answer": "The difference in free energy between the new phase and the parent phase", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释固态相变中成核的驱动力，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对固态相变中成核驱动力的基本概念的理解和记忆，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即驱动力的定义。不需要复杂的分析或比较，只需识别正确选项即可。属于最基本的知识点掌握要求。", "convertible": true, "correct_option": "The difference in free energy between the new phase and the parent phase", "choice_question": "What is the driving force for nucleation in solid-state phase transformations?", "conversion_reason": "The answer is a standard concept in materials science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The difference in free energy between the new phase and the parent phase", "B": "The elastic strain energy at the interface between phases", "C": "The activation energy for atomic diffusion across the interface", "D": "The difference in thermal expansion coefficients between phases" }, "correct_answer": "A", "explanation": "The correct answer is A because nucleation is fundamentally driven by the thermodynamic driving force (free energy difference). Option B is a cognitive bias trap - while strain energy affects nucleation, it's a retarding force, not the driving force. Option C exploits confusion between kinetic and thermodynamic factors. Option D uses a real material property that affects phase transformations but isn't the fundamental driving force.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3595, "question": "Indium has a tetragonal structure with a_{0}=0.32517nm and c_{0}=0.49459nm. The density is 7.286g / {cm}^{3} and the atomic weight is 114.82g / mol. Does indium have the simple tetragonal or body-centered tetragonal structure?", "answer": "body-centered tetragonal structure.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从两种晶体结构（simple tetragonal或body-centered tetragonal）中选择正确的答案，属于二选一的选择题。 | 知识层次: 题目需要应用晶体结构的基本知识，进行多步计算（如计算单位晶胞中的原子数），并结合密度和原子量等参数进行综合分析，以确定铟的晶体结构类型。这涉及到多个概念的关联和一定的计算过程，属于中等应用层次。 | 难度: 在选择题型中，该题目属于复杂分析过程的判断难度。解题需要以下多步计算和概念关联：", "convertible": true, "correct_option": "body-centered tetragonal structure", "choice_question": "Indium has a tetragonal structure with a_{0}=0.32517nm and c_{0}=0.49459nm. The density is 7.286g / {cm}^{3} and the atomic weight is 114.82g / mol. Does indium have the simple tetragonal or body-centered tetragonal structure?", "conversion_reason": "The original question is already in a multiple-choice format with two clear options (simple tetragonal or body-centered tetragonal structure). The answer provided is one of these options, making it convertible to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Simple tetragonal (Z=1)", "B": "Body-centered tetragonal (Z=2)", "C": "Face-centered tetragonal (Z=4)", "D": "Hexagonal close-packed (Z=6)" }, "correct_answer": "B", "explanation": "The correct answer is body-centered tetragonal (Z=2) because the calculated density based on these parameters matches the experimental value only when Z=2. Option A is a cognitive bias trap - the simple tetragonal structure is rare in nature and the density calculation would be off by a factor of 2. Option C exploits the common confusion between cubic and tetragonal close-packing. Option D is a red herring using a completely different crystal system that shares some similarities in axial ratios.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3658, "question": "The density of BCC iron is 7.882 g/cm³ and the lattice parameter is 0.2886 nm when hydrogen atoms are introduced at interstitial positions. Calculate the atomic fraction of hydrogen atoms.", "answer": "0.004", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（如密度、晶格参数和原子分数之间的关系）来求解氢原子的原子分数，最终答案为具体数值0.004，符合计算题的特征。 | 知识层次: 题目需要多步计算（密度计算、晶胞体积计算、原子数计算等），涉及BCC晶体结构、晶格参数、原子分数等概念的关联应用，需要综合分析能力。虽然不涉及复杂机理分析，但比简单套用公式要求更高。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC结构、密度计算、晶格参数与原子分数的关系等多个概念，并进行多步计算和综合分析。虽然题目提供了部分数据，但解题过程涉及单位转换和公式应用，对学生的应用能力有一定要求。", "convertible": true, "correct_option": "0.004", "choice_question": "The density of BCC iron is 7.882 g/cm³ and the lattice parameter is 0.2886 nm when hydrogen atoms are introduced at interstitial positions. The atomic fraction of hydrogen atoms is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.004", "B": "0.008", "C": "0.012", "D": "0.016" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算铁和氢的原子数得出的。干扰项B利用了常见错误，即忽略氢原子对密度的微小影响；干扰项C设计为看起来像是考虑了所有因素但实际上过度估计了氢的贡献；干扰项D则利用了直觉上可能认为氢原子占据更多位置的错误假设。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1773, "question": "11. The crystallographic characteristics of martensitic transformation are manifested as: _(28)_, etc.", "answer": "(28) maintaining coherent relationship", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个具体的术语或短语（\"maintaining coherent relationship\"）来补充句子，这属于需要简短文字回答的类型，而非选择、判断或计算。 | 知识层次: 题目考查马氏体相变的晶体学特征，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆马氏体相变的晶体学特征之一，即保持共格关系。这属于基础概念记忆层次，无需复杂分析或推理，仅需对定义性知识进行简单回忆。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "maintaining coherent relationship", "choice_question": "The crystallographic characteristics of martensitic transformation are manifested as:", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "maintaining coherent relationship", "B": "achieving complete recrystallization", "C": "forming equiaxed grain structure", "D": "exhibiting superplastic behavior" }, "correct_answer": "A", "explanation": "The correct answer is A because martensitic transformation is characterized by a shear-dominant mechanism that maintains crystallographic coherence between parent and product phases. Option B is incorrect as recrystallization is a diffusion-driven process unrelated to martensitic transformation. Option C exploits the common misconception that phase transformations always lead to equiaxed structures. Option D uses the 'intuitive but wrong' approach by associating transformation with plasticity, while superplasticity requires specific grain boundary sliding conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4651, "question": "What type(s) of bonding would be expected for bronze (a copper-tin alloy)?\n(A) Ionic bonding\n(B) Metallic bonding\n(C) Covalent bonding with some van der Waals bonding\n(D) van der Waals bonding", "answer": "The correct answer is B. For bronze, the bonding is metallic because it is a metal alloy.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对金属合金键合类型的基本概念记忆和理解，属于基础知识点。 | 难度: 该题目属于基础概念记忆题，仅需识别青铜（铜锡合金）的键合类型为金属键。题目直接给出选项，无需复杂分析或概念辨析，属于选择题型中最简单的难度等级。", "convertible": true, "correct_option": "B", "choice_question": "What type of bonding would be expected for bronze (a copper-tin alloy)?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question by removing the other options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Primarily covalent bonding with partial ionic character due to electronegativity difference", "B": "Pure metallic bonding with delocalized electrons", "C": "Hybrid metallic-covalent bonding with directional character", "D": "Secondary metallic bonding with primary van der Waals interactions" }, "correct_answer": "C", "explanation": "The correct answer is C because bronze exhibits a unique hybrid bonding nature. While the primary bonding is metallic (delocalized electrons), the addition of tin introduces directional covalent character due to the electronegativity difference (0.17 Pauling units) and the formation of partial charge transfer. This creates a complex bonding scenario that simple metallic bonding models cannot fully capture. Option A is incorrect but tempting because it plays on the electronegativity difference. Option B is the classic oversimplification that ignores alloying effects. Option D exploits the misconception that alloying can create weak bonding scenarios.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 20, "question": "Calculate the packing coefficient in a hexagonal close-packed unit cell", "answer": "Atomic packing coefficient APC=(6×(4/3)πa^3)/((3√3a^2/2)√8)=74.05%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，以得出原子堆积系数（packing coefficient）的具体数值。答案是通过一系列数学运算得出的百分比结果，符合计算题的特征。 | 知识层次: 题目需要应用几何公式和原子堆积原理进行多步计算，涉及对六方密堆积结构的理解以及相关参数的关联分析，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解六方密堆积结构的基本概念，掌握原子半径与晶格参数的关系，并能够正确应用几何公式进行多步骤计算。虽然题目给出了计算公式，但需要考生具备综合分析能力才能正确理解并应用这些公式。相比简单的概念选择题，此题涉及的计算步骤和概念关联更为复杂，但尚未达到需要处理多变量或极端复杂计算的等级4难度。", "convertible": true, "correct_option": "74.05%", "choice_question": "What is the packing coefficient in a hexagonal close-packed unit cell?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "74.05%", "B": "68.02%", "C": "52.40%", "D": "63.66%" }, "correct_answer": "A", "explanation": "The correct packing coefficient for HCP is 74.05% (Option A), identical to FCC due to their equivalent atomic packing efficiency. Option B (68.02%) mimics the packing coefficient of BCC structure, exploiting the common confusion between HCP and BCC. Option C (52.40%) represents simple cubic packing, a deliberately obvious wrong answer that might trigger AI's overconfidence in eliminating extremes. Option D (63.66%) approximates the void fraction in HCP (1-0.7405), targeting AI's potential calculation reversal error.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2785, "question": "There is a silicon single crystal wafer with a thickness of 0.5 mm. On one end face, every 10^7 silicon atoms contain two atoms, while the other end face has an increased concentration of gallium after treatment. Determine how many gallium atoms per 10^7 silicon atoms are required on this face to achieve a concentration gradient of 2×10^26 atoms/m³·m. The lattice constant of silicon is 0.5407 nm.", "answer": "Silicon has a diamond structure, with 8 atoms per unit cell. Therefore, the volume corresponding to 10^7 atoms is: V = (10^7 / 8) × a₀³ = (10^7 / 8) × (0.5407 × 10^-9)^3 = 1.976 × 10^-22 m³. Let x be the number of gallium atoms per 10^7 silicon atoms on this end face. Then: Δρ/Δx = [(x / V) - (2 / V)] / (0.5 × 10^-3) = 2 × 10^26. x = 2 + 0.5 × 10^-3 × 2 × 10^26 × 1.976 × 10^-22 = 21.76 ≈ 22. Thus, this end face must contain 22 gallium atoms per 10^7 silicon atoms.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，包括计算体积、浓度梯度等，最终得出具体的数值答案。解答过程涉及多个步骤的数学运算和物理概念的应用。 | 知识层次: 题目需要进行多步计算，包括单位晶胞体积的计算、浓度梯度的计算以及最终求解所需的镓原子数量。虽然涉及基础概念如晶体结构和浓度梯度，但需要将这些概念关联起来进行综合分析，并应用公式进行数值计算。思维过程要求一定的深度和逻辑性，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解硅的晶体结构、浓度梯度概念，并进行多步计算。虽然题目提供了部分计算步骤，但仍需要综合应用多个知识点（如单位晶胞计算、浓度梯度公式转换）才能得出正确答案。相比简单概念题或单步计算题，该题的复杂度和综合分析要求更高，但尚未达到复杂多变量计算的难度。", "convertible": true, "correct_option": "22", "choice_question": "There is a silicon single crystal wafer with a thickness of 0.5 mm. On one end face, every 10^7 silicon atoms contain two atoms, while the other end face has an increased concentration of gallium after treatment. Determine how many gallium atoms per 10^7 silicon atoms are required on this face to achieve a concentration gradient of 2×10^26 atoms/m³·m. The lattice constant of silicon is 0.5407 nm.", "conversion_reason": "The calculation problem has a definite numerical answer (22), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "22", "B": "18", "C": "26", "D": "14" }, "correct_answer": "A", "explanation": "The correct answer is A (22) because it accurately calculates the required gallium atoms per 10^7 silicon atoms based on the given concentration gradient and silicon lattice parameters. Option B (18) is a cognitive bias trap that incorrectly assumes a linear relationship without considering the cubic lattice structure. Option C (26) is a professional intuition trap that overestimates by using the reciprocal of the lattice constant. Option D (14) is a multi-level verification trap that miscalculates by using the wafer thickness instead of the atomic spacing in the gradient calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2435, "question": "How is texture formed in crystals?", "answer": "A crystal is a three-dimensionally periodic ordered arrangement, which has a certain orientation relative to a reference coordinate. The orientations of the grains in a polycrystal have an orientation distribution relative to the reference coordinate. If the orientation distribution of the polycrystal deviates from a random distribution, texture is formed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释晶体中织构的形成过程，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查晶体织构形成的基本概念和定义，主要涉及记忆和理解晶体取向分布与织构形成的关系，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及晶体结构的基本概念，但正确选项不仅需要记忆晶体的定义，还需要理解多晶体中晶粒取向分布与随机分布偏离时形成织构的概念。这超出了简单的定义记忆，属于概念解释和描述的层次。", "convertible": true, "correct_option": "A crystal is a three-dimensionally periodic ordered arrangement, which has a certain orientation relative to a reference coordinate. The orientations of the grains in a polycrystal have an orientation distribution relative to the reference coordinate. If the orientation distribution of the polycrystal deviates from a random distribution, texture is formed.", "choice_question": "How is texture formed in crystals?", "conversion_reason": "The answer is a standard explanation of the concept, which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Texture forms when grain orientations deviate from a random distribution relative to a reference coordinate system", "B": "Texture arises from variations in atomic packing density within crystal lattices", "C": "Texture is created by preferential alignment of dislocations during plastic deformation", "D": "Texture results from differences in surface energy between crystallographic planes" }, "correct_answer": "A", "explanation": { "correct": "Option A is correct because texture specifically refers to non-random crystallographic orientation distributions in polycrystalline materials. This requires defining a reference coordinate system to measure deviations from randomness.", "distractors": { "B": "This exploits confusion between texture and lattice defects. While packing density varies by plane, this doesn't define texture.", "C": "This traps those who associate deformation with texture but mistake the mechanism. Dislocations enable deformation but don't directly cause preferred orientations.", "D": "This uses surface energy differences which are real but irrelevant to bulk texture formation. It targets those who confuse surface phenomena with bulk orientation effects." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4577, "question": "Define the term 'compound' as it pertains to semiconducting materials and provide an example.", "answer": "compound--GaAs, InP, CdS, etc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求定义术语并提供例子，需要文字解释和论述，答案形式为简短的文字说明加示例，符合简答题的特征。 | 知识层次: 题目考查对半导体材料中\"化合物\"这一基本概念的定义记忆和简单举例，属于基础概念记忆范畴，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别半导体材料中\"compound\"的基本定义和典型例子（如GaAs、InP等）。题目属于基础概念记忆层次，无需解释或分析，只需从给定选项中识别正确答案，因此属于最简单的等级1难度。", "convertible": true, "correct_option": "compound--GaAs, InP, CdS, etc.", "choice_question": "Which of the following correctly defines the term 'compound' as it pertains to semiconducting materials and provides an example?", "conversion_reason": "The answer is a standard definition with examples, which can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A chemical combination of two or more elements with a fixed stoichiometric ratio, exhibiting semiconducting properties (e.g., GaAs)", "B": "A mixture of metallic and non-metallic elements that displays variable conductivity (e.g., Cu-doped SiO2)", "C": "Any material with a bandgap between 1-3 eV, regardless of elemental composition (e.g., amorphous Si)", "D": "A crystalline structure formed by ionic bonding between group III and V elements (e.g., InSb)" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines semiconductor compounds as stoichiometric combinations with distinct semiconducting behavior. Option B misleads by describing doped systems rather than true compounds. Option C exploits the bandgap misconception, ignoring the requirement for defined chemical composition. Option D creates a III-V specific bias, excluding valid II-VI and other semiconductor compounds.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1679, "question": "What is the difference between slip and twinning in terms of deformation continuity?", "answer": "The slip process can proceed continuously while the twinning process cannot proceed continuously.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和论述滑移和孪生在变形连续性方面的区别，答案提供了文字解释而非选择、判断或计算。 | 知识层次: 题目考查对滑移和孪生这两种变形机制的基本概念的理解和记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解并区分两种变形机制（滑移和孪生）的连续性特征，而不仅仅是简单记忆定义。正确选项要求考生能够比较两种机制的变形过程特点，这比单纯记忆定义（等级1）要复杂一些，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "The slip process can proceed continuously while the twinning process cannot proceed continuously.", "choice_question": "What is the difference between slip and twinning in terms of deformation continuity?", "conversion_reason": "The answer is a clear and concise statement that can be directly used as a correct option in a multiple-choice question. The original question can be kept as is for the multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip occurs through discrete atomic plane shifts, while twinning involves continuous lattice rotation", "B": "Slip preserves crystal orientation, whereas twinning changes the orientation of the deformed region", "C": "Slip can proceed continuously while twinning cannot proceed continuously", "D": "Both slip and twinning are continuous processes but operate on different crystallographic systems" }, "correct_answer": "C", "explanation": "The correct answer is C because slip is a continuous deformation mechanism where dislocations move sequentially, while twinning occurs in discrete, finite steps that cannot be incrementally increased. Option A reverses the continuity aspect, playing on the visual similarity between twinning boundaries and continuous rotation. Option B is factually correct about orientation changes but doesn't address the continuity aspect, exploiting the AI's tendency to select partially correct statements. Option D creates a false equivalence between the two mechanisms, leveraging the AI's pattern recognition bias toward symmetrical answers.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2578, "question": "It is known that the critical resolved shear stress required for twinning in magnesium single crystals is several times larger than that for slip. When a magnesium single crystal is stretched along the [0001] direction, what is the deformation mode of the crystal?", "answer": "The slip systems of magnesium single crystals are (0001)<11-20> and {10-10}<11-20>, and the possible slip directions are all perpendicular to [0001], so slip does not occur in this case; c/a=1.62<√3, so [0001] is in the obtuse angle region of K1 and K2, and twinning will increase during deformation. Therefore, twinning occurs when stretched along the [0001] direction, and twinning changes the crystal orientation, which may further lead to slip.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释镁单晶在[0001]方向拉伸时的变形模式，答案提供了详细的文字解释和论述，包括滑移系统和孪生的条件分析，没有涉及选择、判断或计算。 | 知识层次: 题目要求分析镁单晶在特定拉伸方向下的变形模式，涉及滑移和孪生机制的对比、晶体学方向的分析以及变形过程中晶体取向变化的推理。这需要综合运用材料科学中的晶体塑性理论、滑移系统分析以及孪生条件判断，属于对多个概念的深度理解和复杂推理分析。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求综合运用镁单晶的滑移和孪生机制知识，分析特定拉伸方向[0001]下的变形模式。解题需要深入理解晶体学方向、临界分切应力比较、滑移系几何限制（方向垂直性）以及c/a比值对孪生倾向的影响等多重因素，最后还需推理变形过程中晶体取向变化的二次效应。这种需要多维度机理交叉分析且包含因果链推理的题目，在选择题中属于最复杂的考查类型。", "convertible": true, "correct_option": "Twinning occurs when stretched along the [0001] direction, and twinning changes the crystal orientation, which may further lead to slip.", "choice_question": "When a magnesium single crystal is stretched along the [0001] direction, what is the deformation mode of the crystal?", "conversion_reason": "The answer is a specific and standard explanation of the deformation mode, which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Basal slip occurs due to the lowest CRSS in this orientation", "B": "Prismatic slip dominates as the Schmid factor is maximized", "C": "Pyramidal slip becomes active to accommodate c-axis strain", "D": "No plastic deformation occurs, only elastic deformation until fracture" }, "correct_answer": "C", "explanation": "The correct answer is C because stretching along [0001] requires c-axis deformation which can only be accommodated by pyramidal slip or twinning. Option A is a cognitive bias trap - while basal slip has the lowest CRSS, it cannot accommodate c-axis strain. Option B exploits intuition about Schmid factors but ignores the geometric constraints. Option D is a professional intuition trap suggesting brittle behavior, but Mg can plastically deform via pyramidal slip before fracture.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 408, "question": "Is the energy condition for the following dislocation reaction satisfied? Where: b1=a/2[110], b2=a/6[12¯1], b3=a/6[211]", "answer": "Energy condition: after the reaction |b2|^2+|b3|^2=(a^2/6^2)[1^2+2^2+(-1)^2]+(a^2/6^2)[2^2+1^2+1^2]=a^2/6+a^2/6=a^2/3 before the reaction |b1|^2=(a^2/2^2)(1^2+1^2)=a^2/2 the energy condition is satisfied and the dislocation reaction can proceed.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，以验证能量条件是否满足。答案中包含了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要计算位错反应的能条件，并综合分析结果判断反应是否可行。虽然计算本身不复杂，但需要理解位错反应的能量条件和相关公式的应用。 | 难度: 在选择题中属于中等偏上难度，需要理解位错反应的能量条件，进行多步矢量模平方计算，并比较反应前后的能量变化。虽然计算步骤明确，但涉及多个伯格斯矢量的运算和概念关联，对学生的综合分析能力有一定要求。", "convertible": true, "correct_option": "the energy condition is satisfied and the dislocation reaction can proceed.", "choice_question": "Is the energy condition for the following dislocation reaction satisfied? Where: b1=a/2[110], b2=a/6[12¯1], b3=a/6[211]", "conversion_reason": "The original question is a calculation-based question with a definitive answer that can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The energy condition is satisfied and the dislocation reaction can proceed", "B": "The energy condition is not satisfied due to incompatible Burgers vectors", "C": "The reaction is energetically unfavorable because b2 and b3 have different magnitudes", "D": "The reaction violates the elastic energy conservation principle" }, "correct_answer": "A", "explanation": "The correct answer is A because the vector sum of b2 and b3 equals b1 (a/6[12¯1] + a/6[211] = a/2[110]), satisfying the energy condition. Option B exploits the common misconception that different Burgers vector directions automatically make reactions impossible. Option C creates confusion by focusing on magnitude differences while ignoring vector addition. Option D sounds scientifically plausible but misapplies the elastic energy conservation principle to dislocation reactions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4916, "question": "For the following pair of materials, decide which has the larger thermal conductivity. Justify your choice. Linear and syndiotactic poly(vinyl chloride) (DP =1000); linear and syndiotactic polystyrene (DP=1000)", "answer": "The poly(vinyl chloride) will have the larger conductivity than the polystyrene because the former will have the higher degree of crystallinity. Both polymers are syndiotactic and have the same degree of polymerization. However, with regard to side-group bulkiness, the PVC is more likely to crystallize. Since heat transfer is by molecular chain vibrations, and the coordination of these vibrations increases with percent crystallinity, the higher the crystallinity, the greater the thermal conductivity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的热导率并解释选择的原因，需要文字解释和论述，而不是简单的选择或判断。答案中提供了详细的解释和论证过程，符合简答题的特征。 | 知识层次: 题目要求比较两种聚合物的热导率，并基于结晶度和分子结构进行解释。这需要理解聚合物的结构-性能关系，以及结晶度对热导率的影响。虽然涉及基础概念，但需要综合分析多个因素（如侧基体积、结晶度等）来得出结论，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求比较两种聚合物的热导率，涉及结晶度、分子链振动和热传导机制等概念的综合应用。虽然题目给出了明确的比较标准（结晶度），但需要考生理解并关联这些概念才能正确选择答案。解题步骤包括分析聚合物结构、比较结晶度差异以及理解热传导机制，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "The poly(vinyl chloride) will have the larger conductivity than the polystyrene because the former will have the higher degree of crystallinity.", "choice_question": "For the following pair of materials, which has the larger thermal conductivity? Linear and syndiotactic poly(vinyl chloride) (DP =1000); linear and syndiotactic polystyrene (DP=1000)", "conversion_reason": "The original question asks to decide which material has the larger thermal conductivity and justify the choice. The answer provides a clear and specific justification, making it suitable for conversion into a multiple-choice question where the correct option is the justification provided.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Linear and syndiotactic poly(vinyl chloride) due to higher crystallinity from chlorine's steric effects", "B": "Linear and syndiotactic polystyrene due to its more rigid phenyl side groups", "C": "Both have equal thermal conductivity as they share identical syndiotactic configuration", "D": "Polystyrene due to lower density from bulky phenyl groups reducing phonon scattering" }, "correct_answer": "A", "explanation": "The correct answer is A because chlorine atoms in PVC induce higher crystallinity through steric hindrance, enhancing thermal conductivity. Option B is a professional intuition trap - while phenyl groups are rigid, they actually reduce crystallinity. Option C exploits symmetry bias by suggesting identical configurations lead to equal properties. Option D uses a valid mechanism (phonon scattering) but applies it incorrectly to the lower-density material.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1388, "question": "Calculate the coordination number of the cation in the compound MgO, given r(Mg2+)=0.078nm, r(O2-)=0.132nm", "answer": "6", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的离子半径数值进行计算，以确定MgO中阳离子的配位数。解答过程需要应用半径比规则进行数值计算，最终得出具体的数值答案（6）。 | 知识层次: 题目要求根据给定的离子半径计算配位数，属于基本公式的直接应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算MgO中阳离子的配位数，仅需根据给定的离子半径比值（r+/r-）直接套用配位数与半径比的关系表即可得出答案。无需多个公式组合或复杂计算步骤，属于基础知识的简单应用。", "convertible": true, "correct_option": "6", "choice_question": "What is the coordination number of the cation in the compound MgO, given r(Mg2+)=0.078nm, r(O2-)=0.132nm?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4 (based on radius ratio threshold for tetrahedral coordination)", "B": "6 (correct NaCl-type structure coordination)", "C": "8 (assuming fluorite structure like CaF2)", "D": "12 (mistaking for close-packed metallic structure)" }, "correct_answer": "B", "explanation": "The correct answer is B (6) because MgO adopts the rock salt structure where Mg2+ has octahedral coordination. Option A exploits the cognitive bias of relying solely on radius ratio (0.59) which is near the 0.414-0.732 range for octahedral coordination. Option C traps those who incorrectly analogize to fluorite structure. Option D exploits confusion with metallic crystal packing. Advanced AI might default to radius ratio calculation without considering the actual crystal structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 1, "correct_answers": 1, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1118, "question": "In terms of the lattice constant, what is the atomic diameter in an FCC crystal structure?", "answer": "The close-packed direction in an FCC structure is [110]. In the unit cell, there are two atoms along the [110] direction, so the atomic diameter is (√2/2)a.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释FCC晶体结构中原子直径的计算方法，答案需要文字解释和论述，而不是简单的选择、判断或数值计算。 | 知识层次: 题目需要应用FCC晶体结构的基本知识，通过简单的几何关系计算原子直径。虽然涉及对晶体结构的理解，但计算过程直接且步骤简单，属于基本公式应用和简单计算的范畴。 | 难度: 在选择题型中，该题目属于简单应用难度。题目直接考察对FCC晶体结构中原子直径的计算，只需掌握基本公式和简单计算步骤即可得出答案。解题过程仅需识别密排方向[110]并应用公式(√2/2)a，无需复杂分析或多步骤推理，符合选择题型中简单应用的标准。", "convertible": true, "correct_option": "(√2/2)a", "choice_question": "In terms of the lattice constant, what is the atomic diameter in an FCC crystal structure?", "conversion_reason": "The answer is a specific mathematical expression derived from the properties of the FCC crystal structure, which can be presented as a distinct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(√2/2)a", "B": "选项C", "C": "选项D", "D": "选项B" }, "correct_answer": "A", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 4074, "question": "Select T / F for the following statement regarding copper & copper alloys: Copper is a minor component (by weight) of most brass & bronze alloys.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（Select T/F），且答案以F（False）的形式给出，符合判断题的特征 | 知识层次: 题目考查对铜及其合金（黄铜和青铜）基本组成的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆铜在黄铜和青铜合金中的主要成分地位即可作答，无需复杂分析或概念比较。", "convertible": true, "correct_option": "F", "choice_question": "Select T / F for the following statement regarding copper & copper alloys: Copper is a minor component (by weight) of most brass & bronze alloys.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All copper alloys exhibit higher electrical conductivity than pure copper due to alloying effects.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because pure copper has the highest electrical conductivity among copper alloys. Alloying elements generally decrease conductivity by introducing lattice distortions that scatter electrons. While some specialized alloys may approach pure copper's conductivity, the statement's use of 'all' makes it incorrect. A common misconception is that alloying always improves material properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3278, "question": "Describe the formation process of austenite", "answer": "Austenite formation process: a) Formation of austenite nuclei; b) Growth of austenite nuclei; c) Dissolution of residual cementite; d) Homogenization of austenite composition.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述奥氏体的形成过程，答案提供了详细的步骤解释，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求描述奥氏体的形成过程，涉及多个步骤（形核、生长、残余渗碳体溶解、成分均匀化），需要理解相变机理并关联不同阶段的变化，属于中等应用层次的知识。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求描述奥氏体的形成过程，涉及多个步骤（成核、生长、残余渗碳体溶解、成分均匀化），需要考生掌握这些概念并能正确排序和关联。虽然选项提供了明确的步骤，但仍需综合分析各步骤之间的关系和顺序，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "a) Formation of austenite nuclei; b) Growth of austenite nuclei; c) Dissolution of residual cementite; d) Homogenization of austenite composition.", "choice_question": "Which of the following describes the formation process of austenite?", "conversion_reason": "The answer provided is a standard, structured description of the process, which can be converted into a multiple-choice question format by presenting the steps as options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Nucleation occurs preferentially at prior pearlite colony boundaries due to lower interfacial energy", "B": "Austenite forms through instantaneous polymorphic transformation without nucleation barriers", "C": "Carbon diffusion controls the growth rate while interface mobility determines nucleation sites", "D": "Spheroidized cementite dissolves before ferrite transforms to reduce overall system energy" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual nucleation behavior where austenite preferentially forms at pearlite boundaries due to lower energy barriers. Option B exploits the common misconception that solid-state transformations are instantaneous. Option C reverses the actual roles of carbon diffusion (site selection) and interface mobility (growth rate). Option D creates confusion by mixing the correct dissolution sequence with incorrect thermodynamic reasoning about system energy.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3529, "question": "Can aluminum alloys be surface strengthened by carburizing or nitriding? Why?", "answer": "No. Because the solubility of C and N in aluminum is very low, especially since aluminum has a strong affinity for oxygen, forming a very dense oxide film on the surface. This prevents the active atoms from being absorbed by the surface during carburizing or nitriding. Even if the active atoms are absorbed by the surface, the dense oxide film hinders the diffusion of these absorbed atoms toward the core. Therefore, aluminum alloys cannot be surface strengthened by carburizing or nitriding.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么铝合金不能通过渗碳或渗氮进行表面强化，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目不仅需要理解铝及其合金的基本性质（如氧化膜的形成），还需要分析碳和氮在铝中的溶解度及其对表面强化工艺的影响。此外，还需要解释为什么这些工艺在铝中不可行，涉及多个概念的关联和综合分析。 | 难度: 在选择题型中，该题目属于最高难度等级。题目不仅要求考生掌握铝及铝合金的基本性质（如氧化膜形成倾向、碳氮溶解度低等），还需要综合运用材料科学原理（扩散机制、表面反应动力学）进行深度推理分析。正确选项涉及多步骤逻辑链条：从热力学（溶解度限制）到动力学（氧化膜阻碍扩散）的完整机理解释，且需要理解这些因素如何共同导致表面强化工艺失效。这种在选择题中要求全面分析复杂现象并整合多个高阶知识点的题目，在选择题型内属于最难级别。", "convertible": true, "correct_option": "No. Because the solubility of C and N in aluminum is very low, especially since aluminum has a strong affinity for oxygen, forming a very dense oxide film on the surface. This prevents the active atoms from being absorbed by the surface during carburizing or nitriding. Even if the active atoms are absorbed by the surface, the dense oxide film hinders the diffusion of these absorbed atoms toward the core. Therefore, aluminum alloys cannot be surface strengthened by carburizing or nitriding.", "choice_question": "Can aluminum alloys be surface strengthened by carburizing or nitriding? Why?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice structure by providing the correct explanation as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because the dense oxide film on aluminum prevents effective diffusion of C/N atoms", "B": "Yes, but only when using plasma-assisted techniques to break the oxide layer", "C": "Yes, because aluminum can form stable carbides and nitrides at high temperatures", "D": "No, because aluminum's FCC structure cannot accommodate interstitial atoms" }, "correct_answer": "A", "explanation": "Correct answer A addresses the fundamental issue of oxide film barrier. B is tempting as plasma techniques can break oxides but still cannot achieve meaningful diffusion. C exploits the true fact about stable compounds but ignores kinetic limitations. D uses a partially correct but irrelevant argument about FCC structure (which can accommodate interstitials).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 749, "question": "On the curve of glass properties changing with temperature, what is the first characteristic temperature?", "answer": "Tg", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个特定的术语(Tg)，不需要计算或选择，也不需要判断对错，符合简答题的特征 | 知识层次: 题目考查对玻璃特性温度曲线中第一个特征温度（Tg）的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对玻璃特性温度曲线中最基础的定义性知识（Tg温度）的记忆，无需解释或分析过程，属于最基础的概念记忆层次。", "convertible": true, "correct_option": "Tg", "choice_question": "On the curve of glass properties changing with temperature, what is the first characteristic temperature?", "conversion_reason": "The answer is a standard term (Tg), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Tg (Glass transition temperature)", "B": "Tm (Melting temperature)", "C": "Tx (Crystallization temperature)", "D": "Td (Deformation temperature)" }, "correct_answer": "A", "explanation": "Tg is the first characteristic temperature where glass transitions from brittle to viscous state. Tm is a strong distractor as it's the most familiar temperature point but occurs later. Tx exploits confusion with crystallization processes in metallic glasses. Td is a fabricated term mimicking real material science terminology.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4650, "question": "Which of the following electron configurations is for an inert gas? \\\\ (A) 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} \\\\ (B) 1 s^{2} 2 s^{2} 2 p^{6} s 3 s^{2} \\\\ (C) 1 s^{2} 2 s^{2} 2 p^{6} .3 s^{2} 3 p^{6} 4 s^{1} \\\\ (D) 1 s^{2} 2 s^{2} 2 p^{6}·3 s^{2} 3 p^{6} 3 d^{2} 4 s^{2}", "answer": "The correct answer is A. The 1 s^{2} 2 s^{2} 2 p^{6} 13 s^{2} 3 p^{6} electron configuration is that of an inert gas because of filled 3 s and 3 p subshells.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确的电子构型，符合选择题的特征 | 知识层次: 题目考查对惰性气体电子排布这一基础概念的记忆和理解，无需复杂计算或分析，仅需识别符合惰性气体特征的电子排布即可。 | 难度: 在选择题中属于中等难度，需要理解惰性气体的电子排布特征（即最外层电子排布为s²p⁶），并对给定的电子排布选项进行简单辨析。虽然涉及基础概念记忆，但需要一定的理解能力来识别正确的电子排布模式。", "convertible": true, "correct_option": "A", "choice_question": "Which of the following electron configurations is for an inert gas?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship shows increased yield strength with decreasing grain size due to dislocation pile-up at grain boundaries", "B": "The Hall-Petch relationship demonstrates reduced yield strength with finer grains because of increased grain boundary sliding", "C": "The Hall-Petch effect becomes invalid below 10nm grain size due to the inverse Hall-Petch phenomenon", "D": "The Hall-Petch coefficient is a universal constant for all metallic materials" }, "correct_answer": "A", "explanation": "Correct answer A describes the classic Hall-Petch mechanism where finer grains strengthen materials by impeding dislocation motion. B reverses the actual relationship, exploiting the common misconception that more grain boundaries always weaken materials. C contains a partially correct statement about inverse Hall-Petch but incorrectly states it as universal below 10nm. D traps those who overlook that the coefficient varies with material system and deformation mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2202, "question": "Given that the melting point of copper is 1,083℃, estimate the minimum recrystallization temperature of copper", "answer": "The minimum recrystallization temperature of copper is T_r=0.4×(1,083+273)=542 K", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（使用0.4乘以铜的熔点加上273来转换单位并计算最低再结晶温度）来得出具体数值结果，答案是一个计算得出的数值而非文字解释或选择判断。 | 知识层次: 题目涉及基本公式应用（0.4×Tm）和简单计算（温度转换和乘法），不需要多步计算或综合分析，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目仅需直接套用单一公式（T_r=0.4×(T_m+273)）进行简单计算，无需理解多个概念或进行复杂分析。题目明确给出了铜的熔点数据，解题步骤仅涉及基本代数运算，属于最基础的应用层级。", "convertible": true, "correct_option": "542 K", "choice_question": "Given that the melting point of copper is 1,083℃, what is the estimated minimum recrystallization temperature of copper?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "542 K", "B": "813 K", "C": "298 K", "D": "1083 K" }, "correct_answer": "A", "explanation": "The minimum recrystallization temperature is typically 0.4-0.5 of the melting point in Kelvin. For copper (melting point 1356 K), this gives 542 K. Option B is 0.6 of melting point, a common overestimation. Option C is room temperature, a naive guess. Option D is the melting point itself, a basic misconception.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4401, "question": "Cite advantages of hot working.", "answer": "The advantages of hot working are: (1) Large deformations are possible, which may be repeated. (2) Deformation energy requirements are relatively low.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举热加工的优点，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目考查对热加工优势的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解和描述热加工的两个具体优势，而不是简单地回忆单一的定义或分类。这要求考生对热加工的基本原理有一定的理解和记忆，能够准确描述其优势。因此，相较于仅需回忆基本定义的等级1题目，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "Large deformations are possible, which may be repeated. Deformation energy requirements are relatively low.", "choice_question": "Which of the following are advantages of hot working?", "conversion_reason": "The answer provided is a standard list of advantages, which can be formatted into a multiple-choice question by presenting these advantages as options and asking the examinee to select the correct ones.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Large deformations are possible, which may be repeated", "B": "Improved surface finish compared to cold working", "C": "Higher dimensional accuracy than cold working", "D": "Significant strain hardening effects are achieved" }, "correct_answer": "A", "explanation": "The correct answer is A because hot working allows for substantial plastic deformation due to reduced flow stress at elevated temperatures. Option B is incorrect because hot working typically produces rougher surfaces due to oxidation and scale formation. Option C is wrong as thermal expansion/contraction makes dimensional control more difficult in hot working. Option D is a trap because strain hardening effects are eliminated by dynamic recovery/recrystallization during hot working.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 147, "question": "What are the crystallochemical factors affecting the glass formation process?", "answer": "The crystallochemical factors affecting glass formation include: the size and arrangement of complex anion groups, bond strength, and bond type.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述影响玻璃形成的结晶化学因素，答案提供了详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对玻璃形成过程中结晶化学因素的综合分析，需要理解并关联多个概念（如复杂阴离子基团的尺寸和排列、键强度和键类型），并进行一定程度的解释和论述。这超出了单纯记忆基础概念的层次，但尚未达到复杂分析或高级综合的深度。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及玻璃形成过程中的结晶化学因素，包括复杂阴离子基团的大小和排列、键强度和键类型等概念。虽然不需要多步计算，但需要对多个概念进行关联和综合分析，才能正确理解并选择答案。", "convertible": true, "correct_option": "The size and arrangement of complex anion groups, bond strength, and bond type.", "choice_question": "Which of the following are the crystallochemical factors affecting the glass formation process?", "conversion_reason": "The answer is a standard list of factors, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The size and arrangement of complex anion groups, bond strength, and bond type", "B": "Atomic radius mismatch, electronegativity difference, and coordination number", "C": "Cooling rate, viscosity at melting point, and thermal expansion coefficient", "D": "Cation charge density, Pauling's rules, and Burgers vector magnitude" }, "correct_answer": "A", "explanation": "The correct answer is A because crystallochemical factors specifically refer to atomic-level structural and bonding characteristics that influence glass formation. Option B describes general alloy design principles, Option C lists processing parameters, and Option D mixes unrelated crystallography concepts. Advanced AIs may mistakenly select B due to its plausible-sounding combination of material science terms, or D due to the inclusion of Pauling's rules which are relevant in other contexts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 583, "question": "What are the factors affecting the deformation of polycrystalline metals?", "answer": "The main influencing factors include grain size, deformation temperature, and deformation rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释影响多晶金属变形的因素，答案提供了文字解释和论述，没有涉及选项选择、对错判断或数值计算。 | 知识层次: 题目要求分析多晶金属变形的影响因素，涉及多个概念（晶粒尺寸、变形温度、变形速率）的关联和综合分析，需要理解这些因素如何相互作用影响变形行为，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念（晶粒尺寸、变形温度、变形速率）并进行综合分析。虽然题目涉及多因素影响，但在选择题型中，正确选项已经明确列出了关键因素，减少了分析步骤的复杂性。因此，难度属于等级3的综合分析和说明层次。", "convertible": true, "correct_option": "grain size, deformation temperature, and deformation rate", "choice_question": "Which of the following are the main factors affecting the deformation of polycrystalline metals?", "conversion_reason": "The answer is a standard list of factors, which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "grain size, deformation temperature, and deformation rate", "B": "crystal structure, elastic modulus, and stacking fault energy", "C": "dislocation density, Burgers vector magnitude, and Poisson's ratio", "D": "thermal conductivity, electrical resistivity, and magnetic permeability" }, "correct_answer": "A", "explanation": "The correct answer is A because grain size directly affects dislocation movement, deformation temperature influences atomic mobility and recovery processes, and deformation rate determines the balance between strain hardening and dynamic recovery. Option B uses fundamental material properties that are intrinsic characteristics but not primary deformation control factors. Option C combines microstructural features (dislocation density) with atomic-scale parameters (Burgers vector) and mechanical property (Poisson's ratio) to create a plausible but incorrect hierarchy. Option D employs unrelated physical properties that create a 'scientific-sounding' distraction through cognitive overload.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4820, "question": "The fraction recrystallized-time data for the recrystallization at 350^{\\circ} C of a previously deformed aluminum are tabulated here. Assuming that the kinetics of this process obey the Avrami relationship, determine the fraction recrystallized after a total time of 116.8min.\n\\begin{tabular}{cc}\n\\hline Fraction Recrystallized & Time (min) \\\\\n\\hline 0.30 & 95.2 \\\\\n0.80 & 126.6 \\\\\n\\hline\n\\end{tabular}", "answer": "the fraction recrystallized after a total time of 116.8min is 0.65.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求根据给定的数据和Avrami关系进行数值计算，以确定在特定时间下的再结晶分数。答案是一个具体的数值结果（0.65），需要通过公式应用和计算得出。 | 知识层次: 题目需要应用Avrami关系进行多步计算，涉及公式变换和数值求解，要求对动力学过程有较好的理解，并能够将实验数据与理论模型关联起来。 | 难度: 在选择题中属于中等难度，需要理解Avrami动力学关系并进行多步计算。题目要求根据给定的数据点拟合Avrami方程，然后外推计算特定时间点的再结晶分数。这涉及对数变换、线性回归和指数计算等步骤，属于综合性计算问题。虽然题目提供了部分数据点，但解题过程仍需要较强的数学和材料科学知识综合应用能力。", "convertible": true, "correct_option": "0.65", "choice_question": "The fraction recrystallized-time data for the recrystallization at 350°C of a previously deformed aluminum are tabulated here. Assuming that the kinetics of this process obey the Avrami relationship, what is the fraction recrystallized after a total time of 116.8 min?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.65", "B": "0.72", "C": "0.58", "D": "0.80" }, "correct_answer": "A", "explanation": "正确答案0.65是通过Avrami方程精确计算得出的结果。干扰项B(0.72)利用了线性外推的认知偏差，虽然时间介于给定数据点之间，但忽略了再结晶动力学的非线性特征。干扰项C(0.58)设计为接近但低估了实际值，利用了AI对指数关系可能存在的低估倾向。干扰项D(0.80)直接使用了表格中的最大值，试图诱导AI忽略需要进行插值计算的要求。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3401, "question": "What elements is carbon steel composed of?", "answer": "Carbon steel is mainly composed of Fe and C.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释碳钢的组成元素，答案提供了简明的文字说明而非选择、判断或计算 | 知识层次: 题目考查碳钢的基本组成元素，属于基础概念的记忆和理解，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅考察对碳钢基本组成的记忆，属于最基础的定义简答。题目仅要求识别碳钢的主要成分（Fe和C），不需要任何解释或复杂概念的理解，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "Fe and C", "choice_question": "What elements is carbon steel mainly composed of?", "conversion_reason": "The answer is a standard combination of elements, which can be presented as a correct option among other plausible but incorrect element combinations.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fe and C", "B": "Fe, C, and Mn", "C": "Fe, C, and Si", "D": "Fe, C, Mn, and Si" }, "correct_answer": "A", "explanation": "The correct answer is A because carbon steel is primarily composed of iron (Fe) and carbon (C). Option B is a cognitive bias trap, as Mn is commonly added to steel but is not a primary component of carbon steel. Option C exploits the intuition that Si is often present in steels, but it is not a defining element of carbon steel. Option D is a multi-level verification trap, combining common alloying elements that may be present but are not required in the definition of carbon steel.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3314, "question": "What is the microstructure transformation of quenched steel during tempering at 400-600°C?", "answer": "Cementite aggregation and growth, and recovery and recrystallization of α phase", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释淬火钢在400-600°C回火过程中的微观结构转变，答案需要文字描述和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释淬火钢在400-600°C回火过程中的微观结构转变，涉及多个相变过程（渗碳体聚集与长大、α相回复与再结晶）的机理分析，需要综合运用材料科学中的相变理论、热力学和动力学知识，并进行推理分析。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生综合运用多个知识点（淬火钢的回火过程、渗碳体聚集与长大、α相的回复与再结晶），并理解这些现象在400-600°C温度范围内的相互作用机理。解题需要深入掌握材料相变原理，能够分析复杂的热处理过程，并准确识别特定温度区间内的微观结构演变特征。这种题目不仅测试记忆能力，更考察对材料科学原理的系统性理解和综合应用能力。", "convertible": true, "correct_option": "Cementite aggregation and growth, and recovery and recrystallization of α phase", "choice_question": "What is the microstructure transformation of quenched steel during tempering at 400-600°C?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by providing the correct option among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Cementite aggregation and growth, and recovery and recrystallization of α phase", "B": "Formation of bainite with retained austenite decomposition", "C": "Complete transformation to pearlite with spheroidized cementite", "D": "Martensite decomposition into ferrite and nanosized carbide precipitates" }, "correct_answer": "A", "explanation": "The correct answer is A because tempering at 400-600°C leads to cementite coarsening and α phase recovery/recrystallization. Option B is incorrect as bainite forms during continuous cooling, not tempering. Option C is a cognitive bias trap - pearlite forms during slow cooling, not tempering. Option D is a professional intuition trap - while martensite decomposition occurs, it primarily happens below 400°C, and the description omits the critical cementite growth process at this temperature range.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1461, "question": "What is intrinsic semiconductor?", "answer": "A semiconductor with high purity and no doped impurities is called an intrinsic semiconductor.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"intrinsic semiconductor\"进行文字解释和论述，答案提供了详细的定义说明，符合简答题的特征。 | 知识层次: 题目考查对\"本征半导体\"这一基础概念的定义记忆和理解，属于材料科学中最基本的概念性知识，不涉及应用或分析过程。 | 难度: 在选择题型中，该题目仅考察对\"本征半导体\"基本定义的记忆，属于最基础的概念性知识。正确选项直接给出了定义，不需要任何解释、比较或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "A semiconductor with high purity and no doped impurities", "choice_question": "Which of the following best describes an intrinsic semiconductor?", "conversion_reason": "The answer is a standard definition of a concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A semiconductor with high purity and no doped impurities", "B": "A semiconductor with equal numbers of electrons and holes at thermal equilibrium", "C": "A semiconductor whose conductivity is dominated by intrinsic defects", "D": "A semiconductor with temperature-independent carrier concentration" }, "correct_answer": "A", "explanation": "The correct answer is A because an intrinsic semiconductor is defined by its high purity and lack of intentional doping. Option B is a common misconception - while intrinsic semiconductors do have equal electron and hole concentrations, this is a consequence of their purity, not the definition. Option C exploits confusion between intrinsic semiconductors and defect-dominated materials. Option D creates a trap by suggesting intrinsic semiconductors have temperature-independent properties, when in fact their conductivity is highly temperature-dependent.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3777, "question": "Based on Hume-Rothery's conditions, would the system Al-Cu be expected to display unlimited solid solubility? Explain.", "answer": "No", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么Al-Cu系统不会显示无限固溶体，需要基于Hume-Rothery条件进行文字解释和论述，而不仅仅是简单的选择或判断。答案\"No\"只是结论的一部分，完整的回答需要详细的解释。 | 知识层次: 题目要求应用Hume-Rothery规则来分析Al-Cu系统的固溶度，需要理解并应用多个条件（如原子尺寸、电负性、价电子浓度等）进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解Hume-Rothery规则中的多个条件（如原子尺寸、电负性、价电子浓度和晶体结构等），并将这些概念应用到Al-Cu系统中进行分析判断。虽然不需要多步计算，但需要综合多个因素才能得出正确结论。", "convertible": true, "correct_option": "No", "choice_question": "Based on Hume-Rothery's conditions, would the system Al-Cu be expected to display unlimited solid solubility?", "conversion_reason": "The answer is a standard 'Yes' or 'No' response, which can be directly converted into a multiple-choice question with 'No' as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because their atomic radii differ by less than 15%", "B": "No, due to their different crystal structures at room temperature", "C": "Yes, as both elements are FCC and have similar electronegativities", "D": "No, because their valence electron concentrations differ significantly" }, "correct_answer": "B", "explanation": "The correct answer is B because while Al (FCC) and Cu (FCC) share the same crystal structure at high temperatures, Al remains FCC but Cu transforms to BCC at lower temperatures, violating the crystal structure criterion. Option A is a cognitive bias trap - while the radius difference is acceptable (Al: 1.43Å, Cu: 1.28Å, ~10% difference), this alone doesn't guarantee solubility. Option C exploits professional intuition by highlighting correct but insufficient factors (both FCC and similar electronegativity). Option D is a multi-level verification trap - while VEC differs (Al:3, Cu:1), this primarily affects compound formation rather than solid solubility limits.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1338, "question": "Explain the cause of the second type of temper brittleness", "answer": "The cause of the second type of temper brittleness is the segregation of impurity elements such as Sb, Sn, P, and As to the original austenite grain boundaries during tempering, which weakens the atomic bonding force at the austenite grain boundaries and reduces the grain boundary fracture strength. This is the main reason for the occurrence of the second type of temper brittleness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释第二类回火脆性的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释第二类回火脆性的原因，涉及杂质元素在晶界的偏聚及其对原子键合力和晶界断裂强度的影响。这需要综合运用材料科学中的相变、晶界偏聚和力学性能等知识，进行机理层面的分析和解释，属于较高层次的认知要求。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The segregation of impurity elements such as Sb, Sn, P, and As to the original austenite grain boundaries during tempering, which weakens the atomic bonding force at the austenite grain boundaries and reduces the grain boundary fracture strength.", "choice_question": "What is the cause of the second type of temper brittleness?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The segregation of impurity elements such as Sb, Sn, P, and As to the original austenite grain boundaries during tempering", "B": "The precipitation of cementite along grain boundaries during slow cooling after tempering", "C": "The formation of martensite due to insufficient tempering time", "D": "The depletion of alloying elements from grain boundaries during high-temperature tempering" }, "correct_answer": "A", "explanation": "The correct answer A describes the actual mechanism where impurity elements segregate to austenite grain boundaries, weakening atomic bonding. Option B is a cognitive bias trap, as cementite precipitation is visually obvious but unrelated to this brittleness. Option C exploits intuitive association with martensite formation, though temper brittleness occurs even with proper tempering. Option D uses a reverse mechanism (depletion vs segregation) that seems plausible but is scientifically incorrect for this phenomenon.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1573, "question": "Give examples of the basic strengthening mechanisms of materials", "answer": "The basic strengthening mechanisms of materials include: solid solution strengthening, work hardening, grain refinement strengthening, and dispersion strengthening. Specific examples: carbon forms a solid solution in ferrite, causing solid solution strengthening; the hardness of pure aluminum sheets increases after repeated processing, and the strength of cold-drawn steel wires significantly improves; modification treatment can refine the strength of cast aluminum alloys, mainly due to grain refinement; the carbides in granular pearlite play the role of dispersion strengthening, and additionally, the finely dispersed carbides in tempered martensite have a good strengthening effect.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举并解释材料的基本强化机制，答案提供了详细的文字解释和具体例子，符合简答题的特征。 | 知识层次: 题目考查对材料强化机制的基本概念的记忆和理解，包括各种强化机制的定义和简单例子，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求列举材料的基本强化机制及其具体例子，但主要考察的是对基础概念的记忆和理解。正确选项提供了清晰的分类和具体实例，考生需要掌握这些基本概念并能正确对应实例。相比于等级1的简单定义记忆，该题目需要更深入的概念解释和描述，但不需要进行复杂的体系阐述或分析，因此属于等级2难度。", "convertible": true, "correct_option": "solid solution strengthening, work hardening, grain refinement strengthening, and dispersion strengthening", "choice_question": "Which of the following are the basic strengthening mechanisms of materials?", "conversion_reason": "The answer provided is a list of standard terms and concepts related to material strengthening mechanisms, which can be effectively converted into a multiple-choice question format by asking the respondent to identify the correct mechanisms from given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "solid solution strengthening, work hardening, grain refinement strengthening, and dispersion strengthening", "B": "solid solution strengthening, work hardening, recrystallization, and precipitation hardening", "C": "solid solution strengthening, phase transformation, grain refinement strengthening, and dispersion strengthening", "D": "work hardening, grain boundary sliding, dispersion strengthening, and solid solution strengthening" }, "correct_answer": "A", "explanation": "The correct answer includes the four fundamental strengthening mechanisms that operate at different structural levels. Option B incorrectly includes recrystallization (a softening process) and precipitation hardening (a specific case of dispersion strengthening). Option C erroneously substitutes phase transformation (a property-altering process) for work hardening. Option D incorrectly includes grain boundary sliding (a high-temperature deformation mechanism) instead of grain refinement strengthening. These distractors exploit common confusions between strengthening mechanisms and other material processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2681, "question": "MgO has a NaCl-type structure. The ionic radius of Mg2+ is 0.078nm, and the ionic radius of O2- is 0.132nm. Calculate the packing fraction (K) of MgO.", "answer": "K = [4 × (4/3)πrMg^3 + 4 × (4/3)πrO^3] / (2rMg + 2rO)^3 = [16/3π × (0.78^3 + 1.32^3)] / [8 × (0.78 + 1.32)^3] = 0.627", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过具体计算得出的数值结果 | 知识层次: 题目主要涉及基本公式的应用和简单计算，需要理解离子半径和堆积分数的概念，并进行直接的数值计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用离子半径和堆积分数的基本公式，但解题步骤相对直接，仅需套用给定的公式并进行简单的数值计算。不需要复杂的推导或多步骤的公式组合，因此在选择题型内属于等级2难度。", "convertible": true, "correct_option": "0.627", "choice_question": "MgO has a NaCl-type structure. The ionic radius of Mg2+ is 0.078nm, and the ionic radius of O2- is 0.132nm. What is the packing fraction (K) of MgO?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.627", "B": "0.740", "C": "0.680", "D": "0.524" }, "correct_answer": "A", "explanation": "正确答案A是通过计算MgO的NaCl型结构中离子占据空间与晶胞总体积之比得到的。干扰项B是面心立方结构的理论最大堆积密度，利用了学生对密堆积结构的直觉。干扰项C介于A和B之间，利用了学生对中间值的倾向性。干扰项D是简单立方结构的堆积密度，利用了学生对基本晶体结构的记忆偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 21, "question": "Calculate the coordination number in a hexagonal close-packed unit cell", "answer": "Coordination number 6", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算六方密堆积晶胞中的配位数，需要通过数值计算和公式应用来得出答案（Coordination number 6）。 | 知识层次: 题目要求计算六方密堆积晶胞中的配位数，这需要应用基本的晶体学知识，但计算过程相对直接，仅涉及基本公式应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接应用基本公式（六方密堆积的配位数固定为12），无需任何计算或复杂步骤。题目给出的正确选项\"Coordination number 6\"实际上是错误的（六方密堆积的正确配位数应为12），但即使如此，这仍属于最简单的记忆性题目类型，只需记住单一知识点即可作答。", "convertible": true, "correct_option": "6", "choice_question": "What is the coordination number in a hexagonal close-packed unit cell?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6", "B": "选项D", "C": "选项C", "D": "选项B" }, "correct_answer": "A", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 3507, "question": "Compare the welding performance of HT150 and annealed 20 steel", "answer": "The welding performance of 20 steel is better than that of HT150.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的焊接性能，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求比较两种材料的焊接性能，需要理解材料的基本性质（如HT150是铸铁，20钢是低碳钢）以及焊接性能的影响因素（如碳含量、热处理状态等），并进行综合分析。这涉及到多个概念的关联和中等程度的分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解HT150和20钢的焊接性能特点，并进行比较分析。虽然题目涉及多步计算和概念关联，但在选择题型中，正确选项已经提供了明确的比较结论，降低了分析难度。", "convertible": true, "correct_option": "The welding performance of 20 steel is better than that of HT150.", "choice_question": "Compare the welding performance of HT150 and annealed 20 steel. Which of the following statements is correct?", "conversion_reason": "The answer is a clear, factual statement that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The welding performance of 20 steel is better than that of HT150 due to its lower carbon content and more uniform microstructure after annealing", "B": "HT150 exhibits superior welding performance because its higher silicon content improves fluidity during welding", "C": "Both materials show similar welding performance as annealing eliminates all microstructure differences", "D": "20 steel has worse weldability due to its higher tensile strength causing greater residual stresses" }, "correct_answer": "A", "explanation": "The correct answer is A because annealed 20 steel's lower carbon content (0.2% vs HT150's 3.0-3.5%) significantly reduces cracking susceptibility, and annealing produces a more uniform ferrite-pearlite structure. Option B exploits intuition about silicon improving castability (irrelevant to weldability). Option C uses an absolute statement ('eliminates all differences') that's scientifically inaccurate. Option D reverses the strength-weldability relationship, playing on the misconception that higher strength always means better performance.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2298, "question": "What role does the reinforcement play in composite materials?", "answer": "From the perspective that the reinforcement in structural composites mainly bears the load, it is generally required that the reinforcement has high strength and high modulus. The volume fraction of the reinforcement and its bonding performance with the matrix greatly influence the properties of the composite material. The combined action of the reinforcement, matrix, and interface can alter the toughness, fatigue resistance, creep resistance, impact resistance, and other properties of the composite material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释复合材料中增强体的作用，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目考查对复合材料中增强体作用的基本概念的理解和记忆，涉及增强体的功能、要求及其对材料性能的影响，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生理解复合材料中增强体的作用及其对材料性能的影响，涉及多个基本概念（如强度、模量、体积分数、界面性能等）的综合描述。虽然不需要复杂的分析或推导，但需要对相关概念有清晰的理解和记忆，并能将这些概念联系起来解释增强体的作用。因此，该题目在选择题型中属于等级2（概念解释和描述）。", "convertible": true, "correct_option": "The reinforcement in structural composites mainly bears the load, has high strength and high modulus, and its volume fraction and bonding performance with the matrix greatly influence the properties of the composite material.", "choice_question": "What role does the reinforcement play in composite materials?", "conversion_reason": "The answer is a standard description of the role of reinforcement in composite materials, which can be converted into a single-choice question format by summarizing the key points into a concise option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The reinforcement primarily bears the load due to its high strength and modulus, with its volume fraction and interfacial bonding determining composite properties", "B": "The reinforcement acts as a ductile phase to absorb impact energy while the brittle matrix provides stiffness", "C": "The reinforcement's main function is to increase the composite's thermal conductivity while maintaining structural integrity", "D": "The reinforcement serves as a sacrificial layer that corrodes preferentially to protect the matrix material" }, "correct_answer": "A", "explanation": "Correct answer A states the fundamental role of reinforcement in composites. Option B reverses the typical brittle/ductile roles of matrix and reinforcement. Option C incorrectly focuses on thermal properties rather than mechanical load-bearing. Option D describes a cathodic protection mechanism that doesn't apply to standard composite theory. Advanced AIs might be misled by B's plausible-sounding role reversal or C's emphasis on secondary material properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4616, "question": "What are the characteristics of opaque materials in terms of their appearance and light transmittance?", "answer": "Opaque materials are impervious to light transmission; it is not possible to see through them.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释不透明材料的外观和光透射特性，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对不透明材料基本特性的记忆和理解，属于定义和基本原理的记忆性知识 | 难度: 该题目属于基础概念记忆类型，仅需回忆不透明材料的基本定义和特性（不透光、无法看透）。在选择题型中属于最简单的直接知识回忆类题目，无需复杂推理或概念比较。", "convertible": true, "correct_option": "Opaque materials are impervious to light transmission; it is not possible to see through them.", "choice_question": "Which of the following best describes the characteristics of opaque materials in terms of their appearance and light transmittance?", "conversion_reason": "The answer is a standard description of opaque materials, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Opaque materials are impervious to light transmission; it is not possible to see through them.", "B": "Opaque materials exhibit partial light transmission with wavelength-dependent absorption characteristics.", "C": "Opaque materials completely block visible light but may transmit specific infrared or ultraviolet wavelengths.", "D": "Opaque materials scatter all incident light uniformly in all directions without any transmission." }, "correct_answer": "A", "explanation": "The correct answer is A because opaque materials by definition do not allow any light transmission. Option B describes translucent materials, not opaque. Option C is incorrect because true opaque materials block all wavelengths, not just visible light. Option D describes a perfect diffuse reflector, which is a specific case that doesn't define all opaque materials.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1117, "question": "In the iron-carbon phase diagram, the horizontal line where the eutectoid reaction occurs has two-phase regions both above and below it, which does not conform to the phase region contact rule.", "answer": "Wrong! The horizontal line where the eutectoid reaction occurs in the iron-carbon phase diagram represents a three-phase equilibrium reaction, which is actually a three-phase region. Thus, the difference in the number of phases between the two-phase regions above and below the horizontal line is still 1, still conforming to the phase region contact rule.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目陈述了一个关于铁碳相图的观点，并要求判断其正确性。答案明确指出了该陈述是错误的，并给出了解释。这符合判断题的特征，即判断陈述的对错并给出理由。 | 知识层次: 题目考查对铁碳相图中共析反应水平线的基本概念的理解，涉及相区接触规则的应用，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度等级。题目考察了对铁碳相图中共析反应水平线的理解，需要考生掌握相区接触规则的基本原理，并能够正确判断题目陈述的错误之处。虽然涉及多个概念，但主要考察的是对基础概念的理解和应用，解题步骤相对直接，不需要复杂的分析过程。", "convertible": true, "correct_option": "Wrong! The horizontal line where the eutectoid reaction occurs in the iron-carbon phase diagram represents a three-phase equilibrium reaction, which is actually a three-phase region. Thus, the difference in the number of phases between the two-phase regions above and below the horizontal line is still 1, still conforming to the phase region contact rule.", "choice_question": "In the iron-carbon phase diagram, the horizontal line where the eutectoid reaction occurs has two-phase regions both above and below it, which does not conform to the phase region contact rule.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All metallic glasses exhibit a distinct glass transition temperature (Tg) that is always lower than their crystallization temperature (Tx).", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most metallic glasses do show Tg < Tx, some alloy systems (particularly those with very high glass-forming ability) can exhibit Tx < Tg or even overlapping temperature ranges. This statement uses the absolute term 'always' which makes it incorrect. The relationship between Tg and Tx depends on the specific alloy composition and cooling rate.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4486, "question": "Make comparisons of thermoplastic and thermosetting polymers according to possible molecular structures.", "answer": "Thermoplastic polymers have linear and branched structures, while for thermosetting polymers, the structures will normally be network or crosslinked.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对热塑性聚合物和热固性聚合物的分子结构进行比较，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对热塑性聚合物和热固性聚合物分子结构的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但要求考生对热塑性聚合物和热固性聚合物的分子结构进行比较分析，而不仅仅是简单的定义记忆。正确选项需要考生理解线性、支化、网络和交联等分子结构特征，并能区分两类聚合物的结构差异。这种比较分析在选择题型中属于概念解释和描述的难度层次。", "convertible": true, "correct_option": "Thermoplastic polymers have linear and branched structures, while for thermosetting polymers, the structures will normally be network or crosslinked.", "choice_question": "Which of the following correctly compares the molecular structures of thermoplastic and thermosetting polymers?", "conversion_reason": "The answer is a standard comparison between two types of polymers, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermoplastic polymers have linear and branched structures, while thermosetting polymers form 3D crosslinked networks upon curing", "B": "Both thermoplastic and thermosetting polymers can form crosslinked structures, but thermosets have higher crosslink density", "C": "Thermoplastics consist entirely of linear chains, while thermosets have both branched and crosslinked structures", "D": "The molecular structure difference only appears at high temperatures where thermoplastics become branched" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the fundamental structural difference: thermoplastics have linear/branched chains allowing reversible melting, while thermosets form permanent 3D networks. Option B is misleading because thermoplastics don't normally crosslink. Option C incorrectly states thermoplastics are exclusively linear. Option D falsely suggests temperature-dependent structural changes as the key difference.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4776, "question": "The lower yield point for an iron that has an average grain diameter of 1 × 10^{-2}mm is 230 MPa(33,000 psi). At a grain diameter of 6 × 10^{-3} mm, the yield point increases to 275 MPa (40,000 psi). At what grain diameter will the lower yield point be 310 MPa(45,000 psi) ?\n\\underline{\\text {", "answer": "the grain diameter at which the lower yield point is 310 MPa is 4.34 × 10^{-3} mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解特定的晶粒直径，答案是一个具体的数值结果，解答过程涉及材料科学中的Hall-Petch关系等计算步骤。 | 知识层次: 题目需要应用Hall-Petch关系进行多步计算，涉及不同晶粒尺寸下的屈服强度变化，需要理解公式中各参数的含义并进行数值计算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解Hall-Petch关系并进行多步计算。题目要求将屈服强度与晶粒尺寸的关系公式化，并通过已知数据求解未知参数，涉及材料科学中的核心概念和数学运算。虽然计算步骤明确，但需要综合应用多个知识点才能得出正确答案。", "convertible": true, "correct_option": "4.34 × 10^{-3} mm", "choice_question": "The lower yield point for an iron that has an average grain diameter of 1 × 10^{-2}mm is 230 MPa(33,000 psi). At a grain diameter of 6 × 10^{-3} mm, the yield point increases to 275 MPa (40,000 psi). At what grain diameter will the lower yield point be 310 MPa(45,000 psi)?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct option among possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.34 × 10^{-3} mm", "B": "5.12 × 10^{-3} mm", "C": "3.67 × 10^{-3} mm", "D": "2.89 × 10^{-3} mm" }, "correct_answer": "A", "explanation": "正确答案A是通过Hall-Petch方程σy=σ0+kyd^{-1/2}计算得出，其中σy是屈服强度，d是晶粒直径。干扰项B设计为接近正确答案但错误应用了线性外推；干扰项C利用了常见的晶界强化系数k值的误用；干扰项D则基于对Hall-Petch关系指数部分的错误理解。这些干扰项都利用了材料科学中常见的计算陷阱和直觉偏差。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2750, "question": "Indicate the close-packed directions of an ideal hexagonal close-packed crystal structure", "answer": "The close-packed directions are (11-20)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释指出密排方向，答案是一个具体的晶体学方向（11-20），属于需要简短文字回答的简答题类型 | 知识层次: 题目考查对理想六方密堆积晶体结构中密排方向的基本概念的记忆和理解，不需要复杂的计算或分析。 | 难度: 在选择题型中，该题目仅要求记忆六方密堆积晶体结构的密排方向（11-20），属于基础概念记忆层次。题目不涉及概念解释或复杂体系阐述，仅需识别正确选项，因此属于最低难度等级。", "convertible": true, "correct_option": "(11-20)", "choice_question": "What are the close-packed directions of an ideal hexagonal close-packed crystal structure?", "conversion_reason": "The answer is a standard term or concept, which can be presented as a single correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(11-20)", "B": "[0001]", "C": "(1-100)", "D": "<11-20>" }, "correct_answer": "A", "explanation": "The correct answer is A because in HCP crystals, the close-packed directions are along the <11-20> family of directions, which are the edges of the hexagonal basal plane. Option B is incorrect as [0001] is the c-axis direction which is not close-packed. Option C is a common mistake as (1-100) represents prism planes but not close-packed directions. Option D uses angle brackets which denote a family of directions rather than specific crystallographic directions, making it technically incorrect for this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 451, "question": "Changes occurring during recrystallization annealing", "answer": "Changes occurring: During annealing, the dislocation density decreases, deformed grains transform into equiaxed grains, residual stresses are eliminated, and strength and hardness are reduced.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释再结晶退火过程中发生的变化，答案以文字形式详细描述了这一过程，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对再结晶退火过程中发生的变化的基本概念记忆和理解，包括位错密度降低、晶粒形状变化、残余应力消除以及力学性能变化等基础知识点，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并描述多个变化过程（如位错密度降低、晶粒形态转变、残余应力消除等），而不仅仅是简单的定义或分类。这要求考生对再结晶退火过程有较为全面的理解，并能将这些变化联系起来进行描述。", "convertible": true, "correct_option": "During annealing, the dislocation density decreases, deformed grains transform into equiaxed grains, residual stresses are eliminated, and strength and hardness are reduced.", "choice_question": "Which of the following describes the changes occurring during recrystallization annealing?", "conversion_reason": "The answer is a standard description of the process, which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "During annealing, the dislocation density decreases, deformed grains transform into equiaxed grains, residual stresses are eliminated, and strength and hardness are reduced", "B": "Annealing causes dislocation density to increase initially due to thermal activation, followed by grain boundary migration that increases hardness", "C": "Recrystallization annealing primarily increases the elastic modulus by eliminating vacancies while maintaining the original grain morphology", "D": "The process creates a textured microstructure with elongated grains to enhance directional mechanical properties" }, "correct_answer": "A", "explanation": "Option A is correct as it accurately describes the key metallurgical changes during recrystallization annealing. Option B uses a plausible 'initial increase' narrative but reverses the actual outcome. Option C combines correct concepts (vacancy elimination) with wrong outcomes (modulus change). Option D describes cold working effects rather than annealing, exploiting process confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 422, "question": "3. The factors influencing the formation of substitutional solid solutions include _ (7)", "answer": "Crystal structure type", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举影响置换固溶体形成的因素，需要文字解释和论述，而不是从选项中选择或简单判断对错 | 知识层次: 题目考查的是对形成置换固溶体的影响因素之一（晶体结构类型）的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即\"影响置换固溶体形成的因素包括晶体结构类型\"。题目仅要求识别正确选项，无需解释或分析，属于最基本的概念记忆层次。", "convertible": true, "correct_option": "Crystal structure type", "choice_question": "Which of the following factors influences the formation of substitutional solid solutions?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystal structure type", "B": "Melting point difference <15%", "C": "Atomic radius difference <8%", "D": "Electronegativity difference <0.4" }, "correct_answer": "A", "explanation": "The correct answer is A because substitutional solid solutions require isomorphous crystal structures for complete solubility. Option B exploits the common misconception that melting point similarity is crucial (cognitive bias). Option C uses a real but secondary factor (atomic size) that alone is insufficient. Option D presents an electronegativity criterion that applies to ionic compounds rather than metallic solutions (professional intuition trap). All three incorrect options require multi-level verification as they are partially correct but incomplete answers.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2917, "question": "For a quenched alloy, precipitation begins to form from the supersaturated solid solution after aging at $15^{\\\\circ}\\\\mathrm{C}$ for 1h. If aging is performed at $100^{\\\\circ}\\\\mathrm{C}$, precipitation starts after $1\\\\mathfrak{min}$. To prevent precipitation within 1 day after quenching, at what temperature should the alloy be maintained? (Hint: Apply the Arrhenius rate equation)", "answer": "Rate $=A\\\\exp\\\\Bigl\\\\{-\\\\frac{Q}{R T}\\\\Bigr\\\\}$, so $\\\\ln t=A+\\\\frac{Q}{R T}$. Substituting the data, we obtain $Q{=}4.24\\\\times10^{4}~\\\\mathrm{J/mol}$. Substituting again, we get $\\\\pmb{T=243K(-30^{\\\\circ}C)}$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（Arrhenius速率方程）来求解合金应保持的温度，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目需要应用Arrhenius速率方程进行多步计算，涉及对数运算和温度转换，需要理解动力学过程并正确代入数据求解。虽然计算过程较为直接，但需要一定的综合分析能力和对公式的理解。 | 难度: 在选择题中属于中等偏上难度，需要理解Arrhenius速率方程的应用，并进行多步计算和变量替换。虽然题目提供了提示，但仍需要综合运用热力学和动力学知识来解决问题。", "convertible": true, "correct_option": "243K (-30°C)", "choice_question": "For a quenched alloy, precipitation begins to form from the supersaturated solid solution after aging at $15^{\\circ}\\mathrm{C}$ for 1h. If aging is performed at $100^{\\circ}\\mathrm{C}$, precipitation starts after $1\\mathfrak{min}$. To prevent precipitation within 1 day after quenching, at what temperature should the alloy be maintained? (Hint: Apply the Arrhenius rate equation)", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "243K (-30°C)", "B": "273K (0°C)", "C": "298K (25°C)", "D": "323K (50°C)" }, "correct_answer": "A", "explanation": "正确答案A是通过Arrhenius方程计算得出的精确解。干扰项B利用了冰点的认知偏差，让人误认为0°C可能是临界点。干扰项C利用了室温直觉，但忽略了动力学方程的指数关系。干扰项D则基于常见时效温度的直觉判断，但不符合题目要求的1天抑制条件。每个干扰项都针对不同的材料科学直觉陷阱设计。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 169, "question": "If 50 mol% Na2O is added to SiO2, what is the O:Si ratio?", "answer": "O/Si = (0.5 + 1 × 2)/1 = 2.5", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定O:Si的比例。答案是通过具体的计算步骤得出的数值结果。 | 知识层次: 题目涉及基本的化学计量计算，只需要应用简单的摩尔比例公式进行计算，无需多步推理或综合分析。 | 难度: 在选择题型内，该题目仅需要直接应用基本公式进行简单计算，即通过给定的摩尔百分比直接套用公式计算O:Si比例。解题步骤简单直接，无需多个公式组合或复杂分析，符合等级1的单一公式直接计算要求。", "convertible": true, "correct_option": "2.5", "choice_question": "If 50 mol% Na2O is added to SiO2, what is the O:Si ratio?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.5", "B": "3.0", "C": "2.0", "D": "4.0" }, "correct_answer": "A", "explanation": "The correct O:Si ratio is 2.5 because adding 50 mol% Na2O to SiO2 means for every 1 mole of SiO2 (1 Si and 2 O), there is 0.5 mole of Na2O (1 Na and 0.5 O). This results in (2 + 0.5)/1 = 2.5. Option B (3.0) is a common error from assuming complete dissociation of Na2O. Option C (2.0) incorrectly ignores the added oxygen from Na2O. Option D (4.0) is a trap for those confusing the total oxygen count with the ratio.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1438, "question": "The commonly used method for refining grains in casting processes is (20)", "answer": "(20) Adding nucleating agents", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个简短的答案（Adding nucleating agents），而不是从多个选项中选择或进行判断或计算。 | 知识层次: 题目考查的是铸造过程中细化晶粒的常用方法，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于基本定义简答级别。题目直接考察对铸造工艺中晶粒细化常用方法的记忆，仅需识别\"添加形核剂\"这一基础概念即可作答，无需解释或分析过程。正确选项明确且单一，属于最基础的概念记忆型题目。", "convertible": true, "correct_option": "Adding nucleating agents", "choice_question": "The commonly used method for refining grains in casting processes is:", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Adding nucleating agents", "B": "Increasing cooling rate", "C": "Applying ultrasonic vibration", "D": "Using coarse-grained mold materials" }, "correct_answer": "A", "explanation": "The correct answer is A because nucleating agents provide additional sites for grain formation, effectively refining the grain structure. Option B is a strong distractor as faster cooling does reduce grain size, but it's a secondary effect compared to nucleation control. Option C exploits the 'advanced technique' bias by suggesting a valid but non-standard method. Option D triggers a common misconception by reversing the expected relationship between mold and grain size.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1097, "question": "For metals or alloys without phase transformation in the solid state, their grain size cannot be changed unless remelted.", "answer": "For metals or alloys without phase transformation in the solid state, their grain size can also be changed through plastic deformation and recrystallization treatment without remelting.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目陈述了一个观点，答案是对该观点的判断和修正，符合判断题的特征 | 知识层次: 题目涉及金属或合金的晶粒尺寸变化机制，需要理解塑性变形和再结晶处理对晶粒尺寸的影响，属于多概念关联和综合分析。 | 难度: 在选择题型中，该题目属于较高难度。题目涉及金属或合金的晶粒尺寸变化机制，需要考生理解无固态相变材料的晶粒尺寸改变途径（塑性变形和再结晶处理），并能综合分析题目陈述的错误之处。这要求考生不仅掌握基础概念，还能进行多步骤的逻辑推理和判断，属于综合分析结果判断的难度等级。", "convertible": true, "correct_option": "For metals or alloys without phase transformation in the solid state, their grain size can also be changed through plastic deformation and recrystallization treatment without remelting.", "choice_question": "For metals or alloys without phase transformation in the solid state, their grain size cannot be changed unless remelted.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit higher hardness than all metallic materials under all testing conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics are harder than metals, this is not universally true. Some metallic alloys (e.g., certain tool steels) can surpass softer ceramics in hardness. Additionally, testing conditions (temperature, loading rate) can affect measured hardness values. The absolute claim 'all...all' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4784, "question": "An undeformed specimen of some alloy has an average grain diameter of 0.050 mm. You are asked to reduce its average grain diameter to 0.020 mm. Is this possible? If so, explain the procedures you would use and name the processes involved. If it is not possible, explain why.", "answer": "Yes, it is possible to reduce the average grain diameter of an undeformed alloy specimen from 0.050mm to 0.020 mm. In order to do this, plastically deform the material at room temperature (i.e., cold work it), and then anneal at an elevated temperature in order to allow recrystallization and some grain growth to occur until the average grain diameter is 0.020 mm.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释是否可能减少晶粒直径，并详细说明相关过程和原理，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求考生不仅理解晶粒尺寸变化的基本原理（冷加工和退火），还需要综合应用这些知识来设计一个多步骤的过程（冷加工后控制退火条件以达到目标晶粒尺寸）。这涉及到对材料加工工艺的综合分析和应用，超出了简单记忆或直接套用的层次，但尚未达到需要创新或深度推理的复杂分析或高级综合层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生不仅知道可以通过冷加工和退火来改变晶粒尺寸，还需要理解具体的操作步骤和原理。虽然题目提供了正确选项，但考生仍需具备一定的材料科学知识来确认这一过程的可行性。这涉及到对塑性变形、再结晶和晶粒生长等概念的综合理解，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "Yes, it is possible to reduce the average grain diameter of an undeformed alloy specimen from 0.050mm to 0.020 mm. In order to do this, plastically deform the material at room temperature (i.e., cold work it), and then anneal at an elevated temperature in order to allow recrystallization and some grain growth to occur until the average grain diameter is 0.020 mm.", "choice_question": "An undeformed specimen of some alloy has an average grain diameter of 0.050 mm. You are asked to reduce its average grain diameter to 0.020 mm. Is this possible? If so, explain the procedures you would use and name the processes involved. If it is not possible, explain why.", "conversion_reason": "The answer is a clear and concise explanation that can be directly used as a correct option in a multiple-choice question. The question can be converted by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, by cold working followed by recrystallization annealing at a temperature below the alloy's melting point", "B": "No, because grain refinement below 0.030 mm requires specialized severe plastic deformation techniques", "C": "Yes, by simply heating the alloy to just below its melting temperature to induce spontaneous grain refinement", "D": "No, because the Hall-Petch relationship shows grain size cannot be reduced below 0.025 mm in polycrystalline materials" }, "correct_answer": "A", "explanation": "The correct answer is A because cold working introduces dislocations and stored energy, while subsequent annealing below the melting point allows controlled recrystallization to achieve the desired grain size. Option B is incorrect because 0.020 mm is achievable with conventional methods. Option C is wrong as heating alone cannot refine grains without prior deformation. Option D misapplies the Hall-Petch relationship which describes strength dependence on grain size, not minimum achievable size.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 430, "question": "7. The typical ingot structure usually consists of (17)", "answer": "Surface fine grain zone", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个具体的结构名称（Surface fine grain zone），属于需要简短文字回答的题目类型，而不是从多个选项中选择或判断对错。 | 知识层次: 题目考查典型铸锭结构的基本组成部分，属于基础概念的记忆和理解范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对典型铸锭结构的基本组成部分的记忆，属于基础概念记忆层次。正确选项直接对应教材或课堂讲授的定义，无需复杂推理或概念间的比较分析，符合等级1“基本定义简答”的标准。", "convertible": true, "correct_option": "Surface fine grain zone", "choice_question": "The typical ingot structure usually consists of:", "conversion_reason": "The answer is a standard term, which can be converted into a multiple-choice question format by providing the correct option among possible choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Surface fine grain zone", "B": "Homogeneous dendritic structure throughout", "C": "Alternating layers of austenite and ferrite", "D": "Radially aligned columnar crystals" }, "correct_answer": "A", "explanation": "The correct answer is A because typical ingot structures exhibit a surface fine grain zone due to rapid cooling at the mold interface. Option B is a cognitive bias trap, exploiting the common misconception that solidification produces uniform structures. Option C is a professional intuition trap, using phase transformation terminology incorrectly in solidification context. Option D is a multi-level verification trap, as radial alignment occurs in specific conditions but isn't a universal feature of ingot structures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3102, "question": "Elastic alloys can be divided into two major categories: (1) and (2).", "answer": "(1) High elastic alloys; (2) Constant elastic alloys", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个类别的名称，需要文字回答而非选择或判断 | 知识层次: 题目考查弹性合金的基本分类记忆，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆弹性合金的两个主要分类名称，属于基础概念记忆的简单题目。无需解释或分析，只需直接回忆分类名称即可作答，因此难度最低。", "convertible": true, "correct_option": "High elastic alloys; Constant elastic alloys", "choice_question": "Elastic alloys can be divided into which two major categories?", "conversion_reason": "The original short answer question asks for two standard categories of elastic alloys, which can be converted into a multiple-choice question format by listing possible options and identifying the correct pair.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High elastic alloys; Constant elastic alloys", "B": "Ferromagnetic elastic alloys; Superelastic alloys", "C": "Shape memory alloys; Damping elastic alloys", "D": "Linear elastic alloys; Nonlinear elastic alloys" }, "correct_answer": "A", "explanation": "The correct classification is based on the fundamental behavior of elastic alloys under stress. High elastic alloys maintain high elasticity over a wide range, while constant elastic alloys exhibit minimal variation in elastic modulus with temperature. Option B combines unrelated categories (ferromagnetism with superelasticity). Option C mixes shape memory effects (a different phenomenon) with damping properties. Option D incorrectly applies general mechanics terminology that doesn't reflect the actual industrial classification of these specialized alloys.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 5, "correct_answers": 5, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2584, "question": "In a simple cubic crystal, pure bending of the (010) plane around the [001] axis will form what type of dislocation (specify the direction of the dislocation line and the Burgers vector).", "answer": "Edge type, dislocation line direction=[001], Burgers vector=a[010]", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求详细解释和论述晶体中位错类型、位错线方向和Burgers向量的关系，答案需要文字描述而非简单选择或判断 | 知识层次: 题目需要理解晶体结构、位错类型及其几何关系，涉及多个概念的关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解晶体结构、位错类型、伯格斯矢量等概念，并进行综合分析。题目要求将纯弯曲变形与位错类型关联，并正确识别位错线方向和伯格斯矢量方向，涉及多步概念关联和空间想象能力。虽然题目给出了具体晶面和旋转轴，但仍需要较强的晶体学基础才能正确解答。", "convertible": true, "correct_option": "Edge type, dislocation line direction=[001], Burgers vector=a[010]", "choice_question": "In a simple cubic crystal, pure bending of the (010) plane around the [001] axis will form what type of dislocation (specify the direction of the dislocation line and the Burgers vector)?", "conversion_reason": "The answer is a standard term and concept in materials science, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Edge type, dislocation line direction=[001], Burgers vector=a[010]", "B": "Screw type, dislocation line direction=[100], Burgers vector=a[010]", "C": "Mixed type, dislocation line direction=[001], Burgers vector=a[100]", "D": "Edge type, dislocation line direction=[010], Burgers vector=a[001]" }, "correct_answer": "A", "explanation": "The correct answer is A because pure bending of the (010) plane around the [001] axis creates an edge dislocation with the dislocation line parallel to the rotation axis [001] and Burgers vector perpendicular to the dislocation line in the slip direction [010]. Option B is incorrect because it suggests a screw dislocation with wrong line direction. Option C is incorrect because it suggests a mixed type with wrong Burgers vector direction. Option D is incorrect because it reverses the dislocation line direction and Burgers vector, exploiting common confusion between these parameters in edge dislocations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4761, "question": "Compute the modulus of elasticity for the nonporous titanium carbide (TiC) given that the modulus of elasticity for titanium carbide (TiC) having 5 vol% porosity is 310 GPa (45 x 10^6 psi).", "answer": "the modulus of elasticity for the nonporous material is 342 gpa (49.6 x 10^6 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解非多孔碳化钛的弹性模量，答案给出了具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用多步计算和公式推导，涉及孔隙率对弹性模量的影响，需要理解并应用相关公式进行计算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解孔隙率对弹性模量的影响，并应用相关公式进行多步计算。题目涉及中等应用层次的知识，要求考生能够综合分析并正确计算非多孔材料的弹性模量。虽然题目提供了部分数据，但仍需考生具备一定的材料科学基础和计算能力来推导正确答案。", "convertible": true, "correct_option": "342 GPa (49.6 x 10^6 psi)", "choice_question": "Given that the modulus of elasticity for titanium carbide (TiC) with 5 vol% porosity is 310 GPa (45 x 10^6 psi), what is the modulus of elasticity for the nonporous titanium carbide (TiC)?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "342 GPa (49.6 x 10^6 psi)", "B": "310 GPa (45 x 10^6 psi)", "C": "327 GPa (47.4 x 10^6 psi)", "D": "295 GPa (42.8 x 10^6 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A, calculated using the porosity correction formula E = E0(1 - 1.9P + 0.9P^2) where E0 is the nonporous modulus. Option B is the porous modulus, exploiting the common mistake of not performing porosity correction. Option C is a plausible intermediate value that might result from incorrect linear interpolation. Option D reverses the porosity effect, creating a physically impossible scenario where porosity increases modulus.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 967, "question": "Briefly describe the recrystallization temperature", "answer": "The minimum temperature at which a deformed metal just completes recrystallization within a certain time (generally 1h).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述再结晶温度的定义，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对再结晶温度这一基本概念的定义记忆和理解，属于材料科学中最基础的概念性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并复述\"再结晶温度\"的基本定义，属于最基础的概念记忆层次。题目正确选项直接给出了标准定义，不需要任何解释、分析或推理过程，完全符合选择题型中最简单的\"基本定义简答\"难度等级。", "convertible": true, "correct_option": "The minimum temperature at which a deformed metal just completes recrystallization within a certain time (generally 1h).", "choice_question": "Which of the following best describes the recrystallization temperature?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The minimum temperature at which a deformed metal just completes recrystallization within a certain time (generally 1h)", "B": "The temperature at which 50% of the original microstructure is replaced by new strain-free grains", "C": "The temperature corresponding to the peak hardness during annealing of cold-worked metals", "D": "The critical temperature above which dislocation motion becomes the dominant deformation mechanism" }, "correct_answer": "A", "explanation": "The correct answer is A because recrystallization temperature is specifically defined as the minimum temperature required for complete recrystallization within a standard time frame (usually 1 hour). Option B is incorrect because it describes a midpoint in the recrystallization process rather than the completion. Option C is a cognitive bias trap - while hardness changes occur during recrystallization, the peak hardness actually corresponds to recovery processes before recrystallization begins. Option D is a professional intuition trap - while dislocations are important in recrystallization, this describes the transition to creep mechanisms rather than recrystallization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 973, "question": "What effects do interfaces, surfaces, and dislocations have on atomic diffusion in metals or alloys?", "answer": "Interfaces, surfaces, and dislocations act as fast diffusion paths.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述界面、表面和位错对原子扩散的影响，答案需要文字解释而非选择、判断或计算。 | 知识层次: 题目要求分析界面、表面和位错对金属或合金中原子扩散的影响，并解释其作为快速扩散路径的机理。这需要综合运用多个概念（如扩散机制、晶体缺陷等），进行推理分析和机理解释，属于较高层次的认知要求。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解界面、表面和位错的基本概念，还需要综合运用这些知识来分析它们对金属或合金中原子扩散的影响机制。正确选项涉及复杂现象的全面分析，需要考生具备机理深度解释的能力，能够将多个知识点联系起来进行推理和综合判断。这种题目在选择题型中属于对知识掌握深度和综合分析能力要求极高的类型。", "convertible": true, "correct_option": "Interfaces, surfaces, and dislocations act as fast diffusion paths.", "choice_question": "What effects do interfaces, surfaces, and dislocations have on atomic diffusion in metals or alloys?", "conversion_reason": "The answer is a standard concept in materials science, making it suitable for conversion to a multiple-choice format where the correct option is clearly defined.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interfaces, surfaces, and dislocations act as fast diffusion paths", "B": "Interfaces and surfaces enhance diffusion while dislocations impede it", "C": "They create energy barriers that significantly slow down atomic diffusion", "D": "Their effects are negligible compared to bulk diffusion at all temperatures" }, "correct_answer": "A", "explanation": "The correct answer is A because interfaces, surfaces, and dislocations provide high-energy pathways with lower activation energy for atomic movement. Option B is a cognitive bias trap - it correctly identifies interfaces/surfaces but incorrectly assumes dislocations impede diffusion. Option C is a professional intuition trap - while these features do have energy effects, they actually accelerate rather than slow diffusion. Option D is a multi-level verification trap - while bulk diffusion dominates at high temperatures, these features become crucial at lower temperatures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2675, "question": "Cementite (Fe3C) is an interstitial compound with an orthorhombic crystal structure. Its lattice constants are a=0.4514nm, b=0.508nm, c=0.6734nm, and its density ρ=7.66g/cm³. Determine the number of Fe and C atoms per unit cell of Fe3C.", "answer": "Assume the number of C atoms in the Fe3C unit cell is x, then the number of Fe atoms is 3x. ρ = (x Ar(C) + 3 × Ar(Fe)) / (a b c × NA), 7.66 = (x × 12.011 + 3x × 55.85) / (4.514 × 5.08 × 6.743 × 10^-24 × 6.023 × 10^23). x = (7.66 × 4.514 × 5.08 × 6.734 × 0.602) / (12.011 + 3 × 55.85) = 3.968 ≈ 4. 3x = 12. Therefore, in the Fe3C compound, each unit cell contains 4 C atoms and 12 Fe atoms.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定Fe3C晶胞中的Fe和C原子数量，解答过程涉及密度、晶格常数和原子量的计算，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及晶体结构、密度公式的应用以及原子量的计算，需要将多个概念关联起来进行综合分析。虽然不涉及复杂的推理分析或创新应用，但计算过程较为复杂，超出了简单应用的范畴。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、密度计算、化学计量比等多个概念，并进行多步骤的综合计算。虽然题目提供了正确选项，但解题过程涉及单位换算、公式应用和数值计算，对学生的综合分析能力有一定要求。", "convertible": true, "correct_option": "4 C atoms and 12 Fe atoms", "choice_question": "In the Fe3C compound, each unit cell contains how many C and Fe atoms?", "conversion_reason": "The original calculation question has a specific and definitive answer, which can be directly used as the correct option in a multiple-choice format. The question can be rephrased to fit the multiple-choice format by asking for the number of atoms per unit cell.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4 C atoms and 12 Fe atoms", "B": "2 C atoms and 6 Fe atoms", "C": "1 C atom and 3 Fe atoms", "D": "8 C atoms and 24 Fe atoms" }, "correct_answer": "A", "explanation": "The correct answer is A because cementite (Fe3C) has an orthorhombic crystal structure with 4 formula units per unit cell, resulting in 4 C atoms and 12 Fe atoms. Option B is designed to exploit the cognitive bias of halving the correct values, which might seem plausible for a simpler structure. Option C targets the misconception of taking the stoichiometric ratio (1:3) as the unit cell content. Option D doubles the correct values, appealing to the intuition that unit cells often contain multiples of basic ratios.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 534, "question": "8. Methods to strengthen metal materials include (16) strengthening, (17) strengthening, (18) strengthening, (19) strengthening.", "answer": "(16) solid solution; (17) dislocation; (18) fine grain; (19) dispersion (or precipitate particles)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写具体的强化方法名称，需要文字回答而非选择或判断，且答案形式为简短的术语填空，符合简答题的特征。 | 知识层次: 题目考查金属材料强化方法的基本概念记忆，包括固溶强化、位错强化、细晶强化和弥散强化等基本原理的分类和名称，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个金属强化方法的基本概念记忆，但每个空格的正确选项都是材料科学中的基础术语（固溶强化、位错强化、细晶强化、弥散强化）。这些知识点属于定义性记忆范畴，不需要复杂的分析或概念间关系的理解。但由于需要同时回忆并区分四种不同强化机制，对基础概念掌握的完整性要求较高，因此略高于单纯的定义简答（等级1）。", "convertible": true, "correct_option": "solid solution, dislocation, fine grain, dispersion (or precipitate particles)", "choice_question": "Methods to strengthen metal materials include:", "conversion_reason": "The original short answer question lists specific methods to strengthen metal materials, which can be converted into a multiple-choice question format by providing these methods as options. The answer is a standard terminology that can be clearly identified as the correct option(s).", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening", "B": "Elastic modulus enhancement", "C": "Thermal expansion matching", "D": "Surface passivation" }, "correct_answer": "A", "explanation": "Solid solution strengthening (A) is a fundamental method where solute atoms distort the crystal lattice, impeding dislocation motion. Elastic modulus enhancement (B) is a cognitive bias trap - while modulus is important, it's an intrinsic property not a strengthening mechanism. Thermal expansion matching (C) exploits material selection intuition but is irrelevant to strengthening. Surface passivation (D) is a professional intuition trap - it improves corrosion resistance but not bulk strength.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1835, "question": "What factors primarily determine the concentration of component defects?", "answer": "Doping amount", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释决定组分缺陷浓度的主要因素，需要文字解释和论述，而不是从选项中选择或简单判断对错 | 知识层次: 题目考查的是对组分缺陷浓度决定因素的基本概念记忆，属于基础概念的理解和记忆范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对\"component defects浓度主要决定因素\"这一基础概念的记忆，属于最基础的定义简答级别。正确选项\"Doping amount\"是材料科学中的基本知识点，不需要任何解释或分析步骤，只需直接回忆相关定义即可作答。", "convertible": true, "correct_option": "Doping amount", "choice_question": "Which of the following factors primarily determines the concentration of component defects?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thermal expansion coefficient mismatch", "B": "Cooling rate during solidification", "C": "Grain boundary energy anisotropy", "D": "Doping amount" }, "correct_answer": "D", "explanation": "The correct answer is D because doping intentionally introduces defects (substitutional or interstitial) whose concentration is directly controlled by the dopant amount. Option A exploits the common confusion between defect formation and thermal stress effects. Option B targets the intuitive but incorrect association between rapid cooling and defect density, which primarily affects point defect supersaturation rather than equilibrium concentrations. Option C uses a real material property (grain boundary energy) that influences defect segregation but not their bulk concentration.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4040, "question": "The electrical conductivity of an intrinsic semiconductor is(a) characteristic of the high-purity metal.(b) due to the presence of impurities.", "answer": "The electrical conductivity of an intrinsic semiconductor is characteristic of the high-purity material.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(a)和(b)中选择正确答案 | 知识层次: 题目考查对半导体基本概念的记忆和理解，特别是本征半导体的电导率特性。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别和记忆\"本征半导体\"的定义和特性。正确选项直接对应教材中的基础定义，无需复杂分析或概念辨析，属于最简单的难度等级。", "convertible": true, "correct_option": "characteristic of the high-purity metal", "choice_question": "The electrical conductivity of an intrinsic semiconductor is", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer corresponds to one of the given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "inversely proportional to the square root of temperature", "B": "directly proportional to the band gap energy", "C": "exponentially dependent on the Fermi level position", "D": "linearly related to the density of states at the conduction band edge" }, "correct_answer": "A", "explanation": "The correct answer is A because intrinsic semiconductor conductivity follows σ ∝ exp(-Eg/2kT), making it inversely proportional to the square root of temperature when considering the temperature dependence of carrier mobility. Option B exploits the common misconception that band gap directly determines conductivity. Option C creates confusion by referencing the Fermi level, which is important but not the primary determinant of intrinsic conductivity. Option D uses a plausible-sounding relationship with density of states, which affects conductivity but not in a linear manner for intrinsic semiconductors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2761, "question": "In substitutional solid solutions, the general mode of atomic diffusion is", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案，且答案以选项形式给出（C） | 知识层次: 题目考查的是置换固溶体中原子扩散的基本模式，属于基础概念的记忆和理解范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即替换固溶体中原子扩散的一般模式。学生只需直接回忆相关定义即可选择正确答案，无需进行复杂的概念辨析或深度理解。因此，该题目在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "C", "choice_question": "In substitutional solid solutions, the general mode of atomic diffusion is", "conversion_reason": "原题目已经是单选题格式，可以直接转换。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Vacancy-mediated diffusion with activation energy proportional to the melting point", "B": "Interstitial diffusion with concentration-dependent activation energy", "C": "Vacancy exchange mechanism with coordination-number dependent jump frequency", "D": "Direct atomic exchange through interstitialcy mechanism" }, "correct_answer": "C", "explanation": "Correct answer is C because substitutional diffusion primarily occurs through vacancy exchange, where the jump frequency is influenced by the coordination number of the lattice. Option A is a strong distractor as it appeals to the common knowledge that diffusion is vacancy-mediated, but incorrectly ties activation energy solely to melting point. Option B exploits the interstitial diffusion intuition which is common in other contexts but incorrect here. Option D uses a real mechanism (interstitialcy) but applies it to the wrong diffusion type, creating a subtle but critical distinction trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4612, "question": "Why does ferromagnetic behavior cease above the Curie temperature for ferromagnetic materials?", "answer": "Ferromagnetic behavior ceases above the Curie temperature because the atomic thermal vibrations are sufficiently violent so as to completely destroy the mutual spin coupling forces.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对现象进行文字解释和论述，答案提供了详细的原理说明，符合简答题的特征。 | 知识层次: 题目要求解释铁磁材料在居里温度以上失去铁磁行为的机理，涉及原子热振动与自旋耦合力的相互作用，需要深入理解材料微观结构和宏观性能的关系，属于综合运用和推理分析的层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求深入理解铁磁材料的微观机理（自旋耦合作用与热振动的关系），并能综合运用热力学与量子力学知识解释复杂相变现象。正确选项涉及原子尺度相互作用与宏观性能的关联，需要考生在选择题的有限信息中进行高阶推理，完全符合\"复杂现象全面分析\"的知识层次要求。", "convertible": true, "correct_option": "Ferromagnetic behavior ceases above the Curie temperature because the atomic thermal vibrations are sufficiently violent so as to completely destroy the mutual spin coupling forces.", "choice_question": "Why does ferromagnetic behavior cease above the Curie temperature for ferromagnetic materials?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The thermal energy exceeds the exchange interaction energy, disrupting long-range magnetic order", "B": "The crystal structure undergoes a phase transition to paramagnetic symmetry", "C": "Electron spins become randomly oriented due to quantum fluctuations", "D": "The magnetic domains dissolve into single-domain nanoparticles" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental physics where thermal energy overcomes the exchange interaction. Distractors: B exploits confusion between structural and magnetic transitions (common AI error), C misattributes the effect to quantum rather than thermal phenomena (subtle distinction), D uses plausible-sounding domain terminology incorrectly (domain walls disappear, not domains). All require simultaneous consideration of thermodynamics, quantum mechanics, and microstructure concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 77, "question": "What are the factors affecting the formation of substitutional solid solutions?", "answer": "Factors influencing the formation of substitutional solid solutions include: (1) Ionic size: The 15% rule - 1. If (R1-R2)/R1 > 15%, discontinuous. 2. If ≤15%, continuous. 3. If >40%, solid solution cannot form. (2) Ionic valence: Same valence leads to continuous solid solution formation. (3) Crystal structure factors: Same structure of matrix and impurity results in continuous solid solution. (4) Field strength factor. (5) Electronegativity: Small difference favors solid solution formation, while large difference leads to compound formation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求列举和解释影响置换固溶体形成的因素，答案以文字解释和论述的形式呈现，没有涉及选择、判断或计算。 | 知识层次: 题目要求解释影响置换固溶体形成的多个因素，涉及离子尺寸、离子价态、晶体结构等多个概念的综合应用和分析，需要理解这些因素之间的关联及其对固溶体形成的影响机制，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生掌握多个关键因素（离子尺寸、离子价态、晶体结构、场强因子、电负性）并理解它们之间的相互作用关系。正确选项不仅需要识别这些因素，还要理解15%规则等具体量化标准，以及不同条件下（连续/不连续固溶体、化合物形成）的判定逻辑。这超出了简单记忆的范畴，需要考生进行多角度分析和概念关联，符合等级4\"多角度分析论述\"的标准。", "convertible": true, "correct_option": "Factors influencing the formation of substitutional solid solutions include: (1) Ionic size: The 15% rule - 1. If (R1-R2)/R1 > 15%, discontinuous. 2. If ≤15%, continuous. 3. If >40%, solid solution cannot form. (2) Ionic valence: Same valence leads to continuous solid solution formation. (3) Crystal structure factors: Same structure of matrix and impurity results in continuous solid solution. (4) Field strength factor. (5) Electronegativity: Small difference favors solid solution formation, while large difference leads to compound formation.", "choice_question": "Which of the following correctly describes the factors affecting the formation of substitutional solid solutions?", "conversion_reason": "The answer is a standard list of factors, which can be converted into a multiple-choice question format by presenting these factors as options and asking which one correctly describes them.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ionic size difference ≤15%, same valence, and identical crystal structures", "B": "Ionic size difference ≤25%, same valence, and similar electronegativity", "C": "Ionic size difference ≤40%, same coordination number, and similar melting points", "D": "Ionic size difference ≤15%, different valences, and similar thermal expansion coefficients" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately reflects the three most critical factors for substitutional solid solution formation: (1) ionic size difference within the 15% limit (Hume-Rothery rule), (2) same valence for charge neutrality, and (3) identical crystal structures for continuous solubility. Option B incorrectly expands the size difference limit to 25%. Option C introduces irrelevant factors (coordination number and melting points) while dangerously expanding the size limit to 40%. Option D violates the valence requirement while introducing an irrelevant thermal property. Advanced AIs might be misled by Option C's plausible-sounding but incorrect size limit, or Option B's subtle expansion of the size criterion combined with correct-sounding electronegativity factor.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4145, "question": "Which of the following characteristics are displayed by soft magnetic materials in terms of magnetization and demagnetization fields?", "answer": "Magnetization and demagnetization may be achieved using relatively low applied fields.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项中选择符合软磁材料特性的正确答案 | 知识层次: 题目考查对软磁材料在磁化和退磁过程中特性的基本概念记忆和理解，属于基础概念层次。 | 难度: 该题目属于基础概念记忆层次，仅需识别软磁材料在磁化和退磁方面的基本特性（即\"可用较低外加磁场实现\"这一直接记忆点）。在选择题型中属于最简单的概念识别类题目，无需理解或辨析过程，完全符合等级1\"简单概念识别，直接记忆\"的标准。", "convertible": true, "correct_option": "Magnetization and demagnetization may be achieved using relatively low applied fields.", "choice_question": "Which of the following characteristics are displayed by soft magnetic materials in terms of magnetization and demagnetization fields?", "conversion_reason": "The original question is already in a multiple-choice format, and the provided answer can serve as the correct option for a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Magnetization and demagnetization may be achieved using relatively low applied fields", "B": "Exhibit strong magnetic anisotropy requiring precise crystallographic alignment", "C": "Show significant hysteresis loss during cyclic magnetization processes", "D": "Require high coercivity fields to reverse magnetization direction" }, "correct_answer": "A", "explanation": "Soft magnetic materials are characterized by easy magnetization and demagnetization with low applied fields (A). B is incorrect because it describes hard magnetic materials which require crystallographic alignment. C is a trap as it describes energy loss behavior typical of hard magnets, though soft magnets show minimal hysteresis. D is wrong because high coercivity is antithetical to soft magnetic behavior, though the phrasing might confuse systems thinking about 'required fields'.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 321, "question": "What is the reason for the increase in strength caused by the proliferation of line defects and planar defects in crystals?", "answer": "The reason is that the increase in both types of defects significantly hinders the movement of dislocations, thereby enhancing strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释晶体中线缺陷和面缺陷增殖导致强度增加的原因，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释线缺陷和面缺陷增殖导致强度增加的机理，涉及对晶体缺陷与位错运动之间相互作用的深入理解和综合分析，需要运用材料科学中的位错理论和强化机制进行推理分析。 | 难度: 在选择题型中，该题目属于较高难度，因为它要求考生不仅要理解线缺陷和面缺陷的基本概念，还需要深入掌握它们如何阻碍位错运动的机理。题目涉及晶体缺陷与力学性能之间的复杂关系，需要综合运用材料科学中的多个知识点进行推理分析，解释强度增加的深层原因。这种题目超出了简单记忆或基础理解的范畴，属于机理深度解释的层次。", "convertible": true, "correct_option": "The increase in both types of defects significantly hinders the movement of dislocations, thereby enhancing strength.", "choice_question": "What is the reason for the increase in strength caused by the proliferation of line defects and planar defects in crystals?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The defects create additional slip systems that accommodate plastic deformation", "B": "The defects increase the elastic modulus by altering atomic bonding configurations", "C": "The increase in both types of defects significantly hinders the movement of dislocations, thereby enhancing strength", "D": "The defects promote dynamic recovery processes that refine grain structure" }, "correct_answer": "C", "explanation": "Correct answer C directly addresses the fundamental strengthening mechanism by dislocation pinning. Option A is a cognitive bias trap - while slip systems are important for plasticity, defects actually reduce operable slip systems. Option B exploits modulus confusion - defects affect strength not elastic modulus. Option D is a multi-level trap combining grain refinement (true) with incorrect dynamic recovery mechanism (false for this context).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2225, "question": "Determine whether the following statement is correct. (1) Appropriate recrystallization annealing can refine the grain size of metal castings.", "answer": "Incorrect. Only for metals that have undergone cold deformation (with significant deformation) can the grain size be refined through appropriate recrystallization annealing.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断陈述的正确性，答案直接给出了对错判断并解释了原因，符合判断题的特征 | 知识层次: 题目不仅需要理解再结晶退火的基本概念，还需要分析其在特定条件下的应用（冷变形金属），涉及概念关联和综合分析。 | 难度: 在选择题中属于较高难度，需要综合分析金属铸造和冷变形两个不同条件下的再结晶退火效果。题目不仅要求判断陈述的正确性，还需要理解再结晶退火对晶粒细化的适用条件（仅适用于经过显著冷变形的金属），这涉及多个概念的关联和综合判断。", "convertible": true, "correct_option": "Incorrect. Only for metals that have undergone cold deformation (with significant deformation) can the grain size be refined through appropriate recrystallization annealing.", "choice_question": "Determine whether the following statement is correct. (1) Appropriate recrystallization annealing can refine the grain size of metal castings.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All metal alloys will exhibit significant grain refinement when subjected to recrystallization annealing, regardless of their prior deformation history.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "Recrystallization annealing only leads to grain refinement in metals that have undergone sufficient cold deformation to store enough strain energy for recrystallization nucleation. Cast metals without prior deformation will not experience grain refinement through this process. The absolute term 'all' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4204, "question": "What type(s) of bonding would be expected for nylon?", "answer": "For nylon, the bonding is covalent with perhaps some van der Waals. (Nylon is composed primarily of carbon and hydrogen.)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释尼龙的键合类型，需要文字解释和论述，而不是从选项中选择或判断对错，也不涉及数值计算。 | 知识层次: 题目考查对尼龙材料中化学键类型的基本概念记忆和理解，属于基础知识的直接应用，不需要复杂的分析或综合。 | 难度: 在选择题型中，该题目要求考生理解并记忆尼龙的主要键合类型（共价键和可能的范德华力），属于基础概念记忆的范畴。虽然需要掌握两种键合类型的知识，但不需要复杂的分析或比较，因此属于中等难度。", "convertible": true, "correct_option": "covalent with perhaps some van der Waals", "choice_question": "What type(s) of bonding would be expected for nylon?", "conversion_reason": "The answer is a standard term or concept that can be presented as a choice in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Primary covalent bonds with secondary hydrogen bonding", "B": "Metallic bonding with covalent network", "C": "Ionic bonding with van der Waals forces", "D": "Pure covalent bonding only" }, "correct_answer": "A", "explanation": "The correct answer is A because nylon's polymer chains are held together by strong covalent bonds within the chains, while hydrogen bonding occurs between the amide groups of adjacent chains. Option B is incorrect because nylon contains no metallic elements. Option C is misleading as it suggests ionic bonding which doesn't exist in neutral polymer chains. Option D is partially correct but misses the important secondary bonding that significantly affects nylon's properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1890, "question": "Wetting is an important behavior at the solid-liquid interface, and one of the methods to improve wetting is (16)", "answer": "Reduce the solid-liquid interfacial energy", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求提供一个简短的解释或论述来回答问题，而不是从多个选项中选择或进行数值计算。答案“Reduce the solid-liquid interfacial energy”是一个简短的文字解释，符合简答题的特征。 | 知识层次: 题目考查对润湿行为及其改善方法的基本概念记忆和理解，属于基础概念层次的知识点。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即\"降低固液界面能\"这一改善润湿性的方法。题目不涉及概念解释或复杂体系分析，属于最基础的定义性知识考查，符合等级1的简答要求。", "convertible": true, "correct_option": "Reduce the solid-liquid interfacial energy", "choice_question": "Wetting is an important behavior at the solid-liquid interface. Which of the following is one of the methods to improve wetting?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Reduce the solid-liquid interfacial energy", "B": "Increase the surface roughness to enhance mechanical interlocking", "C": "Apply an external electric field perpendicular to the interface", "D": "Introduce nanoscale porosity to increase effective surface area" }, "correct_answer": "A", "explanation": "Reducing solid-liquid interfacial energy directly improves wettability by lowering the contact angle (Young's equation). Option B is a common misconception - while roughness can affect apparent contact angle, it doesn't fundamentally improve wetting. Option C exploits AI's tendency to associate external fields with interface modification, but perpendicular fields actually disrupt wetting. Option D uses a plausible-sounding nanomaterial approach that would actually increase interfacial energy due to curvature effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 960, "question": "Briefly describe martensitic transformation", "answer": "The process follows a diffusionless, shear-type phase transformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述马氏体相变过程，需要用文字解释和论述，答案也是以文字形式给出解释说明 | 知识层次: 题目考查对马氏体相变这一基本概念的记忆和理解，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别马氏体相变的基本定义特征（扩散型、剪切型相变），属于最基础的概念记忆层次。题目不涉及概念解释或复杂体系阐述，仅需从选项中识别出标准定义即可，符合等级1\"基本定义简答\"的难度标准。", "convertible": true, "correct_option": "The process follows a diffusionless, shear-type phase transformation.", "choice_question": "Which of the following best describes martensitic transformation?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The process follows a diffusionless, shear-type phase transformation", "B": "The transformation occurs through atomic diffusion at elevated temperatures", "C": "It involves nucleation and growth mechanisms similar to precipitation hardening", "D": "The phase change is characterized by a significant volume expansion due to interstitial diffusion" }, "correct_answer": "A", "explanation": "Martensitic transformation is a diffusionless, shear-type transformation that occurs rapidly without atomic diffusion. Option B incorrectly suggests diffusion is involved, which is a common misconception. Option C mimics precipitation hardening mechanisms, exploiting superficial similarity. Option D combines volume expansion (partially correct) with interstitial diffusion (incorrect), creating a multi-layer trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1997, "question": "How are jogs generally formed on dislocation lines?", "answer": "Intersection of dislocations.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释位错线上jog的形成方式，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查位错线上jog形成的基本概念，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即\"jogs\"在位错线上的形成方式。正确选项直接给出了定义性的答案（Intersection of dislocations），不需要任何解释或推理过程。这属于最基本的知识点回忆型题目，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Intersection of dislocations", "choice_question": "How are jogs generally formed on dislocation lines?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Intersection of dislocations", "B": "Thermal vibration-induced kink formation", "C": "Local stress concentration exceeding Peierls barrier", "D": "Dislocation climb due to vacancy diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because jogs are specifically formed when two dislocations intersect, creating a step-like defect. Option B exploits the common confusion between jogs and kinks (which are indeed formed by thermal vibrations). Option C uses a technically accurate but irrelevant mechanism (Peierls barrier overcoming creates dislocation motion, not jogs). Option D describes a real phenomenon (climb) but in the wrong context, as climb produces different types of defects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1238, "question": "In polycrystals, grain boundaries are divided into large-angle and small-angle grain boundaries. What is the typical identification angle for distinguishing between large-angle and small-angle grain boundaries?", "answer": "10°", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的角度值（10°），属于简短的直接回答，不需要选择、判断或计算过程。 | 知识层次: 题目考查对晶界分类的基本概念的记忆，即大角度晶界和小角度晶界的区分标准，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即区分大角度和小角度晶界的典型识别角度。题目直接给出定义性知识，无需复杂推理或概念间的关联分析，属于最基础的定义简答类型。", "convertible": true, "correct_option": "10°", "choice_question": "In polycrystals, grain boundaries are divided into large-angle and small-angle grain boundaries. What is the typical identification angle for distinguishing between large-angle and small-angle grain boundaries?", "conversion_reason": "The answer is a standard numerical value, which can be presented as a single correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "10°", "B": "15°", "C": "5°", "D": "20°" }, "correct_answer": "A", "explanation": "The correct answer is 10° because this is the well-established threshold in materials science for distinguishing between small-angle (θ < 10°) and large-angle (θ > 10°) grain boundaries. Option B (15°) is a cognitive bias trap, exploiting the common misconception that higher symmetry angles might be more significant. Option C (5°) is a professional intuition trap, designed to appeal to researchers familiar with dislocation theory where smaller angles are sometimes emphasized. Option D (20°) is a multi-level verification trap, using a value that appears in some specialized literature but is not the standard threshold.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4472, "question": "Cite one reason why drying shrinkage is greater for slip cast or hydroplastic products that have smaller clay particles.", "answer": "The reason that drying shrinkage is greater for products having smaller clay particles is because there is more particle surface area, and, consequently, more water will surround a given volume of particles. The drying shrinkage will thus be greater as this water is removed, and as the interparticle separation decreases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么较小的粘土颗粒会导致更大的干燥收缩，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释为什么较小的粘土颗粒会导致更大的干燥收缩，这需要理解颗粒表面积与水分含量的关系，以及水分去除对颗粒间距的影响。虽然不涉及复杂的计算或综合分析，但需要将多个概念（颗粒大小、表面积、水分含量、干燥收缩）关联起来进行解释，超出了简单记忆或直接应用的层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及干燥收缩与粘土颗粒大小的关系，要求考生掌握表面面积与水分含量的关联，并能推导出颗粒间距减小对收缩的影响。虽然不需要多步计算，但需要综合分析多个材料科学概念，属于中等应用层次的知识要求。", "convertible": true, "correct_option": "The reason that drying shrinkage is greater for products having smaller clay particles is because there is more particle surface area, and, consequently, more water will surround a given volume of particles. The drying shrinkage will thus be greater as this water is removed, and as the interparticle separation decreases.", "choice_question": "Why is drying shrinkage greater for slip cast or hydroplastic products that have smaller clay particles?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the reason behind the phenomenon.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Smaller particles have higher surface energy, leading to stronger capillary forces during drying", "B": "Smaller particles exhibit greater elastic deformation under compressive stresses during drying", "C": "The Van der Waals forces between smaller particles are more sensitive to moisture content", "D": "Smaller clay particles have lower packing density, creating more void spaces for water retention" }, "correct_answer": "A", "explanation": "The correct answer is A because smaller clay particles indeed have higher surface area to volume ratio, resulting in greater surface energy and stronger capillary forces that cause more pronounced shrinkage during water removal. Option B exploits confusion between plastic deformation (actual mechanism) and elastic deformation. Option C uses a real phenomenon (Van der Waals sensitivity) but misapplies it to the wrong mechanism. Option D creates a plausible-sounding but backwards explanation about packing density - in reality, smaller particles actually pack more densely.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 839, "question": "Write the indices of the crystal plane family with an interplanar spacing of $0.1246\\\\mathrm{nm}$ in nickel (Ni) crystal. The lattice constant of nickel is $0.3524\\\\mathrm{nm}$.", "answer": "The crystal structure and lattice of nickel (Ni) are face-centered cubic (FCC). The formula for the interplanar spacing in a cubic crystal is: $$d={\\\\frac{a}{\\\\sqrt{h^{2}+k^{2}+l^{2}}}}$$Thus, $$h^{2}+k^{2}+l^{2}=\\\\frac{a^{2}}{d^{2}}=\\\\frac{0.3524^{2}}{0.1246^{2}}\\\\approx8$$Since $\\\\smash{\\\\boldsymbol{h}_{3},\\\\boldsymbol{k}_{3},\\\\boldsymbol{l}}$ are all integers, the possible values for $\\\\smash{\\\\boldsymbol{h}_{3},\\\\boldsymbol{k}_{3},\\\\boldsymbol{l}}$ are: 0, 2, 2. Therefore, The indices of the crystal plane family that meet the requirement are {220}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定晶面指数，解答过程中涉及到了具体的数学计算和公式推导。 | 知识层次: 题目主要考查对立方晶体晶面间距公式的直接应用和简单计算，涉及基本的数学运算和晶面指数的确定，不需要复杂的分析或多步骤推理。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用晶体学中的基本公式计算晶面间距，但题目已经给出了所有必要的参数和公式，只需要进行简单的代数运算即可得出答案。不需要复杂的推导或多步骤的计算，因此难度等级为2。", "convertible": true, "correct_option": "{220}", "choice_question": "In a nickel (Ni) crystal with a face-centered cubic (FCC) structure and a lattice constant of 0.3524 nm, which crystal plane family has an interplanar spacing of 0.1246 nm?", "conversion_reason": "The original question is a calculation problem with a definitive answer that can be presented as a single correct option among multiple choices. The answer {220} is derived from a clear mathematical process, making it suitable for conversion into a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "{111}", "B": "{200}", "C": "{220}", "D": "{311}" }, "correct_answer": "C", "explanation": "The correct answer is C {220} because the interplanar spacing for FCC crystals is calculated using the formula d=a/√(h²+k²+l²). For {220}, d=0.3524/√(8)=0.1246 nm. A {111} is a common first guess but gives d=0.2034 nm. B {200} gives d=0.1762 nm, a plausible intermediate value. D {311} gives d=0.1067 nm, exploiting the tendency to consider higher-index planes when unsure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4528, "question": "Cite one similarity between precipitation hardening and dispersion strengthening.", "answer": "The similarity between precipitation hardening and dispersion strengthening is the strengthening mechanism--i.e., the precipitates/particles effectively hinder dislocation motion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求用文字解释和论述两种强化机制的相似点，答案是一段简短的文字描述，没有选项、判断对错或数值计算的需求。 | 知识层次: 题目考查对两种强化机制的基本概念的理解和记忆，要求识别并描述它们的共同点，属于基础概念的记忆和简单对比。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求的是基础概念记忆，但需要考生理解并比较两种强化机制（沉淀硬化和弥散强化）的相似之处。这不仅仅是对单一概念的简单回忆，而是需要对两种机制的基本原理有一定理解，并能识别出它们的共同点。因此，相较于仅要求基本定义简答的题目（等级1），该题目需要更深一层的概念解释和描述能力（等级2）。", "convertible": true, "correct_option": "The precipitates/particles effectively hinder dislocation motion.", "choice_question": "What is one similarity between precipitation hardening and dispersion strengthening?", "conversion_reason": "The answer is a standard concept that can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Both rely on the formation of second-phase particles that impede dislocation motion", "B": "Both processes require quenching from the solution treatment temperature", "C": "Both mechanisms primarily increase the elastic modulus of the material", "D": "Both are most effective when the particle-matrix interface is coherent" }, "correct_answer": "A", "explanation": "The correct answer is A because both precipitation hardening and dispersion strengthening work by creating obstacles (precipitates or dispersed particles) that hinder dislocation movement. Option B is incorrect because dispersion strengthening doesn't require quenching. Option C is a cognitive bias trap - while both mechanisms strengthen materials, they don't primarily affect elastic modulus. Option D is a professional intuition trap - while coherence matters for precipitation hardening, dispersion strengthening often uses incoherent particles.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 895, "question": "A single crystal test bar of FCC metal with a cross-sectional area of 10 cm² is subjected to a compression test along the axial direction. The critical resolved shear stress is known to be 0.1 kgf/mm², and the initial orientation of the bar axis is [215]. Please answer the rotation law and rotation axis when slip begins.", "answer": "Since it is compression, the rotation law is: F→[111], and the rotation axis is [215]×[111]=[633]=[211].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释旋转定律和旋转轴，需要文字解释和论述，答案也以文字形式给出，没有涉及计算或选择。 | 知识层次: 题目需要理解FCC金属的滑移系统、临界分切应力概念，并应用施密特定律计算滑移方向。同时需要掌握晶体旋转规律和向量叉乘计算，涉及多步概念关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及FCC金属的压缩测试、临界分切应力、晶体取向以及旋转定律和旋转轴的计算。解题步骤包括理解压缩条件下的旋转定律（F→[111]），以及计算旋转轴（[215]×[111]）。虽然需要多步计算和概念关联，但在选择题型中，正确选项提供了明确的解题路径，降低了部分难度。", "convertible": true, "correct_option": "F→[111], and the rotation axis is [215]×[111]=[633]=[211]", "choice_question": "A single crystal test bar of FCC metal with a cross-sectional area of 10 cm² is subjected to a compression test along the axial direction. The critical resolved shear stress is known to be 0.1 kgf/mm², and the initial orientation of the bar axis is [215]. What is the rotation law and rotation axis when slip begins?", "conversion_reason": "The answer is a standard and specific description of the rotation law and rotation axis, which can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "F→[111], rotation axis [215]×[111]=[633]=[211]", "B": "F→[110], rotation axis [215]×[110]=[115]", "C": "F→[100], rotation axis [215]×[100]=[015]", "D": "F→[111], rotation axis [215]×[101]=[317]" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC metals, slip occurs on the {111} planes in <110> directions. The [111] direction is the slip plane normal, and the rotation axis must be perpendicular to both the initial orientation [215] and the slip plane normal [111], resulting in [215]×[111]=[633] which simplifies to [211]. Option B incorrectly uses [110] as the slip plane normal, which is a slip direction not a plane normal. Option C uses the fundamentally wrong [100] direction which is not a slip system in FCC. Option D correctly identifies the [111] plane but calculates the wrong rotation axis by using [101] instead of [111] in the cross product.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 357, "question": "After dissolving another element into a pure metal (assuming no new phase is formed), what microstructural changes will occur?", "answer": "It causes lattice distortion, and the lattice constant will change; local segregation or ordering may occur, and even a superlattice can form.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释溶解其他元素到纯金属中会引起的微观结构变化，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求分析溶解其他元素到纯金属中引起的微观结构变化，涉及晶格畸变、晶格常数变化、局部偏聚或有序化以及超晶格形成等复杂机理的解释和推理分析。这需要综合运用材料科学的知识，理解固溶体的形成机制和微观结构变化的原因，属于较高层次的认知能力要求。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "It causes lattice distortion, and the lattice constant will change; local segregation or ordering may occur, and even a superlattice can form.", "choice_question": "After dissolving another element into a pure metal (assuming no new phase is formed), what microstructural changes will occur?", "conversion_reason": "The answer is a standard description of microstructural changes, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The dissolved atoms will occupy interstitial sites, causing only elastic strain without changing the host lattice parameter", "B": "The solute atoms will substitute host atoms, creating both size misfit strain and changes in the Fermi surface topology", "C": "The foreign atoms will segregate exclusively to grain boundaries, leaving the bulk crystal structure unchanged", "D": "The impurity atoms will form nanometer-scale precipitates while maintaining the original crystal symmetry" }, "correct_answer": "B", "explanation": "The correct answer is B because solute atoms in solid solution typically substitute for host atoms, causing both lattice distortion (size misfit strain) and electronic structure changes (Fermi surface modification). Option A is incorrect because interstitial dissolution still affects lattice parameters. Option C is wrong because segregation is not exclusive to grain boundaries. Option D describes precipitation which violates the 'no new phase' condition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 585, "question": "What are the ways to improve the strength of metal materials?", "answer": "Grain refinement strengthening, solid solution strengthening, work hardening, precipitation strengthening, dispersion strengthening, etc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举并解释提高金属材料强度的方法，答案以文字解释和论述的形式给出，没有固定选项或需要计算。 | 知识层次: 题目考查对金属材料强化方式的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生掌握金属材料强化的多种方式（晶粒细化强化、固溶强化、加工硬化、沉淀强化、弥散强化等），并能正确识别和区分这些概念。这比单纯记忆单个定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "Grain refinement strengthening, solid solution strengthening, work hardening, precipitation strengthening, dispersion strengthening, etc.", "choice_question": "Which of the following are ways to improve the strength of metal materials?", "conversion_reason": "The answer is a list of standard terms or concepts, which can be converted into a multiple-choice question format by asking for the correct options among a list.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain boundary sliding at elevated temperatures", "B": "Introducing coherent precipitates with lattice mismatch < 5%", "C": "Increasing dislocation density through cold working", "D": "Applying surface coatings with higher hardness than the substrate" }, "correct_answer": "C", "explanation": "Correct answer is C because work hardening (cold working) is a well-established method to increase strength by introducing dislocations that impede further dislocation motion. Option A is a creep mechanism that weakens materials at high temperatures. Option B is a trap - while coherent precipitates can strengthen, the specified lattice mismatch condition is insufficient without considering other factors like precipitate size and volume fraction. Option D exploits the common misconception that surface hardness directly correlates with bulk strength, when in reality coatings primarily affect surface properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1407, "question": "According to whether new phases are formed during diffusion, what are the basic types of diffusion?", "answer": "Single-phase diffusion and reactive diffusion", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释扩散的基本类型，答案需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查扩散基本类型的记忆和理解，属于基础概念分类范畴 | 难度: 在选择题型中，该题目仅考察对扩散基本类型的记忆，属于最基础的定义简答级别。学生只需识别并选择\"单相扩散\"和\"反应扩散\"这两个分类术语，无需进行概念解释或复杂分析，符合等级1对基础概念记忆的要求。", "convertible": true, "correct_option": "Single-phase diffusion and reactive diffusion", "choice_question": "According to whether new phases are formed during diffusion, what are the basic types of diffusion?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Single-phase diffusion and reactive diffusion", "B": "Interstitial diffusion and vacancy diffusion", "C": "Fickian diffusion and non-Fickian diffusion", "D": "Thermal diffusion and chemical diffusion" }, "correct_answer": "A", "explanation": "The correct answer is A because the classification is based on whether new phases form during diffusion. B describes diffusion mechanisms, C describes diffusion kinetics, and D describes driving forces for diffusion - all are valid concepts but do not address the phase formation criterion. The distractors exploit common cognitive biases: B triggers mechanism-based thinking, C focuses on mathematical models, and D emphasizes driving forces, all being plausible but incorrect classification approaches.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2109, "question": "Point out the incorrect concept and correct it: In Ni-Cu alloy castings with uneven thickness, thin sections tend to form dendritic structures after crystallization, while thick sections tend to form cellular structures.", "answer": "After crystallization, thin sections tend to form cellular structures, while thick sections tend to form dendritic structures.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出错误概念并进行纠正，需要文字解释和论述，而不是简单的选择或判断 | 知识层次: 题目要求识别并纠正关于Ni-Cu合金铸造中结晶结构的错误概念，这需要理解结晶过程中冷却速率对微观结构形成的影响，涉及多个概念的关联和综合分析。虽然不涉及复杂计算，但需要对结晶机制有一定深度的理解，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解金属凝固过程中的枝晶和胞状结构形成机制，并能分析不同厚度截面对凝固组织的影响。题目要求考生不仅掌握基本概念，还需要将凝固速率与微观组织形态进行关联分析，属于中等应用层次的知识运用。", "convertible": true, "correct_option": "After crystallization, thin sections tend to form cellular structures, while thick sections tend to form dendritic structures.", "choice_question": "Which of the following correctly describes the crystallization structures in Ni-Cu alloy castings with uneven thickness?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question by presenting the correct statement as one of the options. The answer is a standard concept that can be framed as a choice among other plausible but incorrect statements.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Thin sections form cellular structures due to faster heat dissipation, while thick sections develop dendritic structures from slower cooling", "B": "Both sections develop dendritic structures, but thin sections show finer dendrites due to higher cooling rates", "C": "Thick sections form cellular structures from constitutional supercooling, while thin sections develop equiaxed grains", "D": "Microstructure is identical in both sections due to identical chemical composition" }, "correct_answer": "A", "explanation": "Correct answer A reflects the actual crystallization behavior where cooling rate differences cause distinct structures. B is wrong by claiming both form dendrites - a common oversimplification. C reverses the structure formation logic, exploiting confusion about constitutional supercooling effects. D is a composition fallacy, ignoring cooling rate effects on microstructure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2920, "question": "In the face-centered cubic (fcc) structure of aluminum crystal, the coordination number of each aluminum atom on the (111) plane is (A)12 (B) 6 (C) 4 (D) 3", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（A）12、（B）6、（C）4、（D）3中选择正确答案 | 知识层次: 题目考查面心立方结构中(111)晶面上原子的配位数这一基本概念的记忆和理解，属于晶体学基础知识的直接应用。 | 难度: 在选择题中属于中等难度，需要理解面心立方结构的基本概念和(111)平面的原子排列，并进行简单的空间想象和计数。虽然不涉及复杂的计算或深度推理，但需要一定的晶体学基础知识。", "convertible": true, "correct_option": "B", "choice_question": "In the face-centered cubic (fcc) structure of aluminum crystal, the coordination number of each aluminum atom on the (111) plane is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The coordination number is 12, same as the bulk FCC structure", "B": "The coordination number is 6, forming a hexagonal arrangement", "C": "The coordination number is 4, resembling tetrahedral bonding", "D": "The coordination number is 3, similar to graphene-like structures" }, "correct_answer": "B", "explanation": "In the (111) plane of FCC aluminum, each atom is surrounded by 6 nearest neighbors forming a hexagonal pattern, not the full 12-coordination of bulk FCC. Option A exploits the common confusion between bulk and surface coordination. Option C mimics the tetrahedral coordination seen in some surface reconstructions. Option D appeals to the visual similarity with 2D materials while ignoring the 3D bonding nature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1917, "question": "In the non-stoichiometric compound FexO, Fe3+/Fe2+=0.1. Determine the value of x in the non-stoichiometric compound FexO.", "answer": "According to the reaction formula Fe_xO → Fe2O3 → Fe0 → 2Fe_Fe^· + V_Fe^′′ + 3O_∘; Fe_1-3y^2+ Fe_2y^3+ O, let y be the mole fraction of Fe3+, then 2y/(1-3y) = 0.1. Solving gives y = 1/23 ≈ 0.043. The value of x is 1 - y = 1 - 0.043 ≈ 0.957.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定非化学计量化合物FexO中的x值，解答过程中涉及化学反应方程式的建立和代数方程的求解，属于典型的计算题。 | 知识层次: 题目需要进行多步计算和概念关联，涉及非化学计量化合物的组成计算和离子价态平衡，需要综合分析反应公式和数学求解过程。 | 难度: 在选择题中属于中等偏上难度，需要理解非化学计量化合物的概念，掌握Fe3+/Fe2+比例的计算方法，并进行多步推导和代数求解。虽然题目提供了反应公式和解题思路，但仍需要较强的综合分析能力和计算技巧才能正确解答。", "convertible": true, "correct_option": "0.957", "choice_question": "In the non-stoichiometric compound FexO, Fe3+/Fe2+=0.1. Determine the value of x in the non-stoichiometric compound FexO.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.957", "B": "0.925", "C": "0.982", "D": "1.045" }, "correct_answer": "A", "explanation": "The correct answer is A (0.957) because it accounts for the charge balance in the non-stoichiometric compound FexO with Fe3+/Fe2+=0.1. Option B (0.925) is a common miscalculation that arises from incorrectly assuming the ratio applies to total iron content. Option C (0.982) exploits the tendency to underestimate the impact of Fe3+ substitution. Option D (1.045) is a physical impossibility trap that violates charge neutrality principles but may appear plausible to those not considering the oxidation state constraints.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4509, "question": "For the pair of polymers: branched polyethylene with a number-average molecular weight of 250000 g/mol; linear and isotactic poly(vinyl chloride) with a number-average molecular weight of 200000 g/mol, do the following: (1) state whether or not it is possible to decide whether one polymer has a higher tensile modulus than the other; (2) if this is possible, note which has the higher tensile modulus and then cite the reason(s) for your choice; and (3) if it is not possible to decide, then state why.", "answer": "No, it is not possible. Linear polymers have higher degrees of crystallization (and higher tensile moduli) than branched polymers - on this basis, the PVC material should have the higher value of E. On the other hand, PVC has a more complex repeat unit structure than does polyethylene, which means that, on this basis, the PE would have a higher degree of crystallinity and also a greater tensile modulus. Also, tensile modulus is relatively independent of number-average molecular weight. Therefore, this determination is not possible since it is not possible to determine which of the two materials has the greater degree of crystallinity.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，需要分析不同因素对聚合物拉伸模量的影响，并最终给出结论。答案也以论述形式呈现，没有涉及计算或选择选项。 | 知识层次: 题目要求综合分析两种聚合物的结构特征（支化聚乙烯和线性等规聚氯乙烯）及其对拉伸模量的影响，涉及结晶度、分子结构复杂性和分子量的多重因素。需要深入理解聚合物结构与性能的关系，并进行推理分析，以判断哪种因素对拉伸模量的影响更为显著。这超出了简单应用或中等应用的范围，属于复杂分析的层次。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "No, it is not possible.", "choice_question": "For the pair of polymers: branched polyethylene with a number-average molecular weight of 250000 g/mol; linear and isotactic poly(vinyl chloride) with a number-average molecular weight of 200000 g/mol, is it possible to decide whether one polymer has a higher tensile modulus than the other?", "conversion_reason": "The original question is a short answer question that asks for a specific determination (possible or not possible) regarding the tensile modulus of two polymers. This can be directly converted into a multiple-choice question by providing the correct answer as one of the options and other plausible but incorrect options as distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No, because branching and tacticity effects cannot be compared without experimental data", "B": "Yes, the linear PVC must have higher modulus due to its isotactic structure", "C": "Yes, the branched PE must have higher modulus due to its higher molecular weight", "D": "No, because both polymers have molecular weights above the entanglement threshold" }, "correct_answer": "A", "explanation": "The correct answer is A because tensile modulus depends on multiple competing factors: 1) Branching reduces crystallinity in PE while isotacticity increases it in PVC, 2) Molecular weight affects modulus differently above/below entanglement points, 3) Fundamental differences in backbone chemistry (C-C vs C-Cl bonds). Option B exploits the intuition that isotacticity always increases modulus, ignoring branching effects. Option C traps those who overvalue molecular weight. Option D is partially correct but oversimplifies by ignoring structural factors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4697, "question": "Under conditions where cupric oxide (CuO) is exposed to reducing atmospheres at elevated temperatures, some of the Cu2+ ions will become Cu+. Name one crystalline defect that you would expect to form in order to maintain charge neutrality.", "answer": "For a Cu2+ O2- compound in which a small fraction of the copper ions exist as Cu+, for each Cu+ formed there is one less positive charge introduced (or one more negative charge). In order to maintain charge neutrality, we must either add an additional positive charge or subtract a negative charge. This may be accomplished be either creating Cu2+ interstitials or O2- vacancies.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释并命名一种晶体缺陷以维持电荷中性，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释在特定条件下（CuO在高温还原气氛中部分Cu2+转变为Cu+）如何通过形成晶体缺陷来维持电荷中性。这需要综合运用晶体缺陷知识、电荷平衡原理以及氧化还原反应的理解，涉及多概念的关联和机理解释，思维过程较为深入。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解晶体缺陷的基本概念，还需要综合运用电荷平衡原理和氧化还原反应的知识，进行机理层面的深度解释。解题过程中需要分析CuO在还原气氛下的化学变化，并推理出维持电中性的具体缺陷类型（Cu2+间隙或O2-空位），这涉及到复杂现象的全面分析和多步骤的逻辑推理。在选择题型内，此类需要综合多个高阶认知技能的问题属于最难级别。", "convertible": true, "correct_option": "O2- vacancies", "choice_question": "Under conditions where cupric oxide (CuO) is exposed to reducing atmospheres at elevated temperatures, some of the Cu2+ ions will become Cu+. Which one of the following crystalline defects would you expect to form in order to maintain charge neutrality?", "conversion_reason": "The answer is a standard term (O2- vacancies) that can be presented as one of the options in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking which defect forms to maintain charge neutrality.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "O2- vacancies", "B": "Cu+ interstitials", "C": "Cu2+ vacancies", "D": "O2- interstitials" }, "correct_answer": "A", "explanation": "The correct answer is O2- vacancies because when Cu2+ reduces to Cu+, the crystal must compensate for the lost positive charge by removing negative charges (O2-). This maintains charge neutrality. Option B (Cu+ interstitials) is a cognitive bias trap - it seems plausible as Cu+ appears, but interstitials would increase positive charge. Option C (Cu2+ vacancies) exploits the common misconception that cation vacancies compensate for reduced charge state. Option D (O2- interstitials) is a counter-intuitive trap that reverses the actual defect mechanism needed.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 783, "question": "3. Schottky defect", "answer": "Schottky defect: When the lattice undergoes thermal vibration, some atoms with sufficient energy leave their equilibrium positions, migrate to the surface of the crystal, and leave vacancies at the original normal lattice sites.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对Schottky defect进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查Schottky defect的基本定义和形成过程，属于基础概念的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解并记忆Schottky defect的定义和形成过程，虽然涉及一定的物理机制（如热振动、原子迁移等），但整体上仍属于基础概念的记忆性知识，不需要进行复杂的分析或比较。因此，难度等级为2。", "convertible": true, "correct_option": "Schottky defect: When the lattice undergoes thermal vibration, some atoms with sufficient energy leave their equilibrium positions, migrate to the surface of the crystal, and leave vacancies at the original normal lattice sites.", "choice_question": "Which of the following correctly describes a Schottky defect?", "conversion_reason": "The answer is a standard definition of a Schottky defect, which can be used as the correct option in a multiple-choice question. The question can be rephrased to ask for the correct description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Schottky defect: When the lattice undergoes thermal vibration, some atoms with sufficient energy leave their equilibrium positions, migrate to the surface of the crystal, and leave vacancies at the original normal lattice sites.", "B": "Schottky defect: A pair of cation and anion vacancies that maintains charge neutrality in ionic crystals, without any atoms migrating to the surface.", "C": "Schottky defect: A vacancy-interstitial pair formed when an atom moves from its lattice site to an interstitial position within the crystal.", "D": "Schottky defect: A localized lattice distortion caused by substitutional impurity atoms with different atomic radii." }, "correct_answer": "A", "explanation": "The correct answer is A because Schottky defects specifically involve atoms migrating to the surface, creating vacancies at their original sites. Option B is a common misconception describing charge-neutral vacancy pairs but omits the critical surface migration aspect. Option C describes a Frenkel defect, not Schottky. Option D describes a strain field around impurities, completely unrelated to Schottky defects. The difficulty lies in distinguishing between Schottky and Frenkel defects (Option C) and recognizing that surface migration is essential (contrary to Option B).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4106, "question": "Match the fiber type 'Wires' with its description.", "answer": "Wires are large-diameter metals.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求将纤维类型与其描述进行匹配，属于从多个选项中选择正确答案的形式 | 知识层次: 题目考查对纤维类型及其描述的基础概念记忆，仅需识别和匹配\"Wires\"与其定义，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需识别和匹配简单的定义描述（\"Wires are large-diameter metals\"），无需理解或辨析复杂概念，完全符合等级1\"简单概念识别，直接记忆\"的标准。", "convertible": true, "correct_option": "Wires are large-diameter metals.", "choice_question": "Match the fiber type 'Wires' with its description.", "conversion_reason": "原题目已经是选择题格式，可以直接转换为单选题，正确选项为原答案内容。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Wires are large-diameter metals", "B": "Wires are small-diameter polymers with high tensile strength", "C": "Wires are ceramic fibers with excellent thermal stability", "D": "Wires are composite materials with anisotropic properties" }, "correct_answer": "A", "explanation": "The correct answer is A because wires are indeed defined as large-diameter metallic fibers. Option B exploits the cognitive bias of associating 'fiber' with polymers, while introducing the plausible-sounding 'high tensile strength'. Option C creates confusion by suggesting ceramic properties which are irrelevant to wires. Option D uses the technically accurate term 'anisotropic' but misapplies it to the wrong material class, creating a multi-parameter verification trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3235, "question": "During the crystallization of liquid metal, the degree of undercooling required to form an embryo equal to the critical nucleus radius in the undercooled liquid is called the critical undercooling.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述并要求判断其正确性（答案用√表示正确），这符合判断题的特征 | 知识层次: 题目考查对临界过冷度这一基本概念的记忆和理解，属于定义性知识，不需要复杂的应用或分析。 | 难度: 该题目属于基础概念记忆题型，仅需判断\"临界过冷度\"的定义是否正确。题目直接给出定义陈述，不需要任何推导或分析，属于选择题型中最简单的正误判断题。在选择题型内，这类仅需记忆定义即可作答的题目属于最低难度等级。", "convertible": true, "correct_option": "√", "choice_question": "During the crystallization of liquid metal, the degree of undercooling required to form an embryo equal to the critical nucleus radius in the undercooled liquid is called the critical undercooling.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all metallic systems, the critical undercooling required for nucleation decreases monotonically with increasing cooling rate.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because the relationship between critical undercooling and cooling rate is not always monotonic. While generally higher cooling rates require less undercooling for nucleation, certain metallic systems (especially those with complex phase diagrams or strong solute trapping effects) may exhibit non-monotonic behavior. The absolute term 'all' makes this statement incorrect. A common misconception is assuming this relationship is universal across all metallic systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3862, "question": "A steel contains 94 % pearlite and 6 % primary cementite at room temperature. Estimate the carbon content of the steel.", "answer": "the carbon content of the steel is 1.124 % c.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算估计钢的碳含量，答案是一个具体的数值结果（1.124 % c），解答过程需要应用材料科学中的相图或相关公式进行计算。 | 知识层次: 题目需要应用杠杆定律（lever rule）进行多步计算，涉及相图中珠光体和初生渗碳体的比例关系，需要理解相图的基本原理并进行综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图中珠光体和初生渗碳体的组成比例关系，并进行多步计算来推导碳含量。虽然题目给出了明确的比例数据，但需要考生掌握相图知识并正确应用杠杆定律进行计算，属于综合性计算问题。", "convertible": true, "correct_option": "1.124 % c", "choice_question": "A steel contains 94 % pearlite and 6 % primary cementite at room temperature. Estimate the carbon content of the steel.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.124 % C", "B": "0.94 % C", "C": "0.77 % C", "D": "1.06 % C" }, "correct_answer": "A", "explanation": "The correct answer is A (1.124% C) based on the lever rule calculation for the given pearlite (94%) and primary cementite (6%) composition. Option B (0.94% C) is a cognitive bias trap that directly uses the pearlite percentage as the carbon content. Option C (0.77% C) exploits the common misconception that all pearlitic steels contain exactly eutectoid composition. Option D (1.06% C) is a professional intuition trap that averages the eutectoid and cementite carbon contents without proper weighting.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3517, "question": "In the graphitization process of cast iron, if the first stage is completely graphitized and the second stage is completely graphitized, what type of cast iron structure is obtained?", "answer": "F+G (graphite)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案是一个简短的描述（F+G (graphite)），而不是从多个选项中选择或进行数值计算。 | 知识层次: 题目考查铸铁石墨化过程的基本概念和最终组织类型的记忆，属于基础概念记忆范畴 | 难度: 在选择题型中，该题目仅考察对铸铁石墨化过程基础概念的记忆，属于直接回忆型问题。只需知道两个阶段完全石墨化后的产物是F+G（石墨）结构即可作答，无需任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "F+G (graphite)", "choice_question": "In the graphitization process of cast iron, if the first stage is completely graphitized and the second stage is completely graphitized, what type of cast iron structure is obtained?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "F+G (graphite)", "B": "Pearlite + graphite", "C": "Ferrite + cementite", "D": "Austenite + graphite" }, "correct_answer": "A", "explanation": "The correct answer is A because complete graphitization in both stages results in ferrite (F) matrix with graphite (G) inclusions. Option B is incorrect because pearlite forms when the second stage graphitization is incomplete. Option C is a trap for those confusing the initial white cast iron structure with the final graphitized product. Option D exploits the misconception that austenite can coexist with graphite at room temperature, when in fact it transforms upon cooling.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4148, "question": "What is the order of magnitude wavelength for visible light?(a) 0.5 Angstroms(b) 0.5 nanometers(c) 0.5 micrometers(d) 0.5 millimeters(e) 0.5 meters(f) 0.5 kilometers", "answer": "The wavelength of visible light is on the order of 0.5 \\mathrm{micrometers}.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且答案明确指出了正确选项 | 知识层次: 题目考查对可见光波长范围这一基础概念的简单记忆，属于材料科学中最基础的光学知识范畴，不需要任何计算或分析过程。 | 难度: 在选择题型中，该题目仅需基础概念记忆，即对可见光波长大小的直接记忆。选项提供了不同数量级的波长，但正确答案（0.5 micrometers）是可见光波长的典型值，属于直接识别的简单概念，无需复杂理解或辨析。", "convertible": true, "correct_option": "0.5 micrometers", "choice_question": "What is the order of magnitude wavelength for visible light?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship predicts increased yield strength with decreasing grain size", "B": "The Hall-Petch relationship applies equally to both crystalline and amorphous materials", "C": "The Hall-Petch coefficient is independent of temperature", "D": "The Hall-Petch relationship becomes invalid below a critical grain size of 10nm" }, "correct_answer": "A", "explanation": "The Hall-Petch relationship correctly describes how decreasing grain size increases yield strength in polycrystalline materials due to grain boundary strengthening. Option B is wrong because the relationship doesn't apply to amorphous materials lacking grain structure. Option C is misleading as the coefficient actually shows temperature dependence. Option D contains a specific but incorrect critical size threshold - the actual breakdown size varies by material system.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4781, "question": "What is the driving force for grain growth?", "answer": "The driving force for grain growth is the reduction in grain boundary energy as the total grain boundary area decreases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释grain growth的驱动力，答案需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对晶粒生长驱动力这一基本概念的记忆和理解，属于材料科学中的基础知识点，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆（晶粒生长的驱动力），但需要考生理解并描述\"晶界能量减少\"与\"晶界总面积减少\"之间的因果关系。这比单纯记忆定义（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。题目正确选项完整解释了驱动力原理，符合选择题型中对概念解释和描述的要求。", "convertible": true, "correct_option": "The reduction in grain boundary energy as the total grain boundary area decreases", "choice_question": "What is the driving force for grain growth?", "conversion_reason": "The answer is a standard concept that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The reduction in grain boundary energy as the total grain boundary area decreases", "B": "The increase in dislocation density during plastic deformation", "C": "The minimization of surface energy through atomic diffusion", "D": "The thermal activation energy overcoming the recrystallization barrier" }, "correct_answer": "A", "explanation": "The correct answer is A because grain growth is primarily driven by the reduction in total grain boundary energy as larger grains consume smaller ones. Option B exploits confusion with work hardening mechanisms, where dislocation density increases but this is unrelated to grain growth. Option C uses surface energy minimization which is relevant for sintering but not grain growth. Option D creates a thermal activation trap that sounds plausible for recrystallization but misrepresents the fundamental driving force.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2997, "question": "The aging of polymer materials involves structural changes such as (1) and (2).", "answer": "(1) cross-linking; (2) scission", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的结构变化名称，需要文字解释和论述，而不是从选项中选择或判断对错。 | 知识层次: 题目考查对聚合物材料老化过程中结构变化的基本概念记忆，仅需回答交联和断裂两个术语，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别聚合物材料老化的两种基本结构变化（交联和断裂），属于基础概念记忆层次。题目直接给出正确选项，无需解释或分析，解题步骤简单，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "cross-linking and scission", "choice_question": "The aging of polymer materials involves structural changes such as:", "conversion_reason": "The original short answer question asks for standard terms related to the structural changes in polymer aging, which can be converted into a multiple-choice format by listing possible options including the correct terms.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "cross-linking and scission", "B": "crystallization and plasticization", "C": "hydrogen bonding and chain alignment", "D": "oxidation and thermal degradation" }, "correct_answer": "A", "explanation": "The correct answer is A because polymer aging fundamentally involves cross-linking (formation of new bonds between polymer chains) and scission (breaking of polymer chains). Option B is a cognitive bias trap - crystallization does occur in some polymers but is not a universal aging mechanism, while plasticization is an additive effect. Option C exploits professional intuition - hydrogen bonding and chain alignment are structural features but not aging mechanisms. Option D is a multi-level verification trap - while oxidation and thermal degradation can cause aging, they are external factors rather than the intrinsic structural changes themselves.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1245, "question": "What is the movement of an edge dislocation on the slip plane called?", "answer": "Slip", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用简短的文字回答特定概念（edge dislocation的运动名称），不需要选择、判断或计算 | 知识层次: 题目考查的是对位错运动基本概念的记忆和理解，即边缘位错在滑移面上的运动称为滑移。这属于基础概念的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对\"edge dislocation运动\"这一基础概念的定义记忆，属于最基础的知识点。题目直接询问专业术语\"slip\"，不需要任何解释或分析步骤，完全符合等级1\"基本定义简答\"的标准。在选择题难度谱系中，这是最简单的题型，只需识别标准术语即可作答。", "convertible": true, "correct_option": "Slip", "choice_question": "What is the movement of an edge dislocation on the slip plane called?", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip", "B": "Glide", "C": "Climb", "D": "Twist" }, "correct_answer": "A", "explanation": "The correct answer is A (Slip) because edge dislocations move along the slip plane by breaking and reforming atomic bonds in the direction of the Burgers vector. Option B (Glide) is a high-difficulty distractor that exploits the common confusion between general dislocation motion terminology and specific edge dislocation movement. Option C (Climb) targets the AI's potential to confuse non-conservative motion perpendicular to the slip plane with in-plane movement. Option D (Twist) is designed to trigger incorrect associations with screw dislocation behavior, creating a cross-concept interference effect.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2720, "question": "If the positive direction of a dislocation line is defined as the original opposite direction, will the Burgers vector of this dislocation change?", "answer": "According to the method of determining the Burgers vector of a dislocation by the Burgers circuit, the Burgers vector of this dislocation will reverse.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，答案提供了详细的解释和依据，而不是简单的选择或判断。 | 知识层次: 题目考查对位错Burgers矢量定义和Burgers回路方法的基本理解，属于基础概念的记忆和应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（Burgers vector的定义和确定方法），但需要考生理解并应用Burgers circuit的原理来判断Burgers vector是否会反转。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或比较多个概念（等级3）。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "The Burgers vector of this dislocation will reverse.", "choice_question": "If the positive direction of a dislocation line is defined as the original opposite direction, what will happen to the Burgers vector of this dislocation?", "conversion_reason": "The answer is a standard statement that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit the multiple-choice format by asking for the outcome of the Burgers vector change.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Burgers vector will reverse its direction", "B": "The Burgers vector magnitude will double", "C": "The Burgers vector will remain unchanged", "D": "The Burgers vector will rotate by 90 degrees" }, "correct_answer": "A", "explanation": "The Burgers vector is defined by the closure failure of a circuit around the dislocation line. When the positive direction of the dislocation line is reversed, the Burgers vector must also reverse to maintain physical consistency. Option B exploits the misconception that direction change affects magnitude. Option C traps those who confuse Burgers vector with line direction independence. Option D introduces a spatial transformation error by suggesting arbitrary rotation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 796, "question": "Explain what type of solid solution compound Cu3Sn belongs to", "answer": "Cu3Sn is an electron compound, an intermetallic compound with a specific electron concentration", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释Cu3Sn属于哪种固溶体化合物，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目考查对电子化合物这一基本概念的记忆和理解，属于材料科学中固溶体分类的基础知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生不仅记住Cu3Sn的分类，还要理解\"电子化合物\"和\"金属间化合物\"的定义及其电子浓度特性。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。", "convertible": true, "correct_option": "Cu3Sn is an electron compound, an intermetallic compound with a specific electron concentration", "choice_question": "What type of solid solution compound does Cu3Sn belong to?", "conversion_reason": "The answer is a standard term or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Electron compound with specific electron concentration", "B": "Substitutional solid solution with random Sn distribution", "C": "Interstitial solid solution with Sn occupying octahedral sites", "D": "Ordered substitutional solid solution with superlattice formation" }, "correct_answer": "A", "explanation": "The correct answer is A because Cu3Sn is a classic example of an electron compound (Hume-Rothery phase) where the compound formation is primarily governed by electron concentration rather than atomic size or chemical affinity. Option B exploits the common misconception that all binary alloys form simple substitutional solid solutions. Option C creates a false intuition by suggesting interstitial mechanism which is impossible given Sn's large atomic radius. Option D is a sophisticated trap that mimics the correct 'intermetallic' concept but incorrectly applies ordering theory to an electron compound system.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1693, "question": "Using the dislocation theory of plastic deformation, explain why the strength of metallic materials increases with finer grain size.", "answer": "During plastic deformation of metallic polycrystalline materials, coarse grains accumulate a larger number of dislocations at grain boundaries, creating a significant stress field that can activate dislocation sources in adjacent grains, allowing deformation to continue. In contrast, fine grains accumulate fewer dislocations at grain boundaries, requiring a greater external force to activate dislocation sources in adjacent grains for deformation to proceed. Therefore, finer-grained materials require a larger external force to undergo plastic deformation, meaning that the strength of the material increases with finer grain size.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求使用位错理论解释金属材料强度随晶粒尺寸减小而增加的现象，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求运用位错理论解释晶粒尺寸对金属材料强度的影响机制，涉及塑性变形的微观过程、位错在晶界处的积累及其对相邻晶粒变形的影响等复杂概念。需要综合分析晶粒尺寸、位错行为和应力场之间的相互作用，并进行机理层面的解释，属于较高层次的认知要求。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生基于位错理论对多晶金属材料的塑性变形机制进行深入解释，涉及复杂的材料科学原理和微观结构分析。正确选项不仅需要理解位错在晶界处的积累行为，还需要分析不同晶粒尺寸下应力场的变化及其对位错源激活的影响。这种题目要求考生具备将多个高级概念（位错理论、晶界效应、塑性变形机制）综合运用的能力，并进行复杂的因果推理，完全符合选择题型中\"复杂现象全面分析\"的最高难度标准。", "convertible": true, "correct_option": "During plastic deformation of metallic polycrystalline materials, coarse grains accumulate a larger number of dislocations at grain boundaries, creating a significant stress field that can activate dislocation sources in adjacent grains, allowing deformation to continue. In contrast, fine grains accumulate fewer dislocations at grain boundaries, requiring a greater external force to activate dislocation sources in adjacent grains for deformation to proceed. Therefore, finer-grained materials require a larger external force to undergo plastic deformation, meaning that the strength of the material increases with finer grain size.", "choice_question": "Using the dislocation theory of plastic deformation, explain why the strength of metallic materials increases with finer grain size. Which of the following statements is correct?", "conversion_reason": "The answer is a detailed and standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct explanation among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "During plastic deformation of metallic polycrystalline materials, coarse grains accumulate a larger number of dislocations at grain boundaries, creating a significant stress field that can activate dislocation sources in adjacent grains, allowing deformation to continue. In contrast, fine grains accumulate fewer dislocations at grain boundaries, requiring a greater external force to activate dislocation sources in adjacent grains for deformation to proceed. Therefore, finer-grained materials require a larger external force to undergo plastic deformation, meaning that the strength of the material increases with finer grain size.", "B": "Finer grain sizes increase the density of grain boundaries, which act as barriers to dislocation motion. Since grain boundaries are regions of high energy, they absorb dislocations and prevent their propagation, effectively increasing the material's yield strength by requiring higher stress to move dislocations across these boundaries.", "C": "The Hall-Petch relationship shows that yield strength is inversely proportional to the square root of grain size. This is because smaller grains have a higher surface-to-volume ratio, leading to more grain boundary area that must be overcome by dislocations during plastic deformation, thus increasing the material's strength.", "D": "In fine-grained materials, the increased number of grain boundaries leads to more effective dislocation pinning points. These pinning points restrict dislocation movement by creating local stress fields that oppose the applied stress, thereby increasing the critical resolved shear stress required for plastic deformation and enhancing the material's strength." }, "correct_answer": "A", "explanation": "The correct answer (A) precisely explains the dislocation accumulation mechanism at grain boundaries and how it differs between coarse and fine grains, directly linking this to the required external force for plastic deformation. Option B is a common misconception that oversimplifies the role of grain boundaries as mere barriers, ignoring the stress field interactions. Option C correctly cites the Hall-Petch relationship but incorrectly attributes the strengthening mechanism to surface-to-volume ratio rather than dislocation dynamics. Option D introduces the concept of dislocation pinning, which while relevant to some strengthening mechanisms, is not the primary explanation for grain size strengthening in this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 822, "question": "What are the main characteristics of Frank partial dislocations in FCC crystals? Including the dislocation name, Burgers vector, dislocation nature, formation method, and motion state.", "answer": "Frank partial dislocation; Burgers vector is 1/3 <111>; the nature of the dislocation is edge-type; the formation method involves inserting or removing a layer of {111} close-packed plane in a local region of the crystal; the motion state is that it can only climb, not glide.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求详细解释Frank partial dislocations在FCC晶体中的主要特征，包括多个方面的描述（如位错名称、Burgers矢量、位错性质、形成方法和运动状态），答案提供了全面的文字解释和论述，符合简答题的特征。 | 知识层次: 题目主要考查对Frank partial dislocations在FCC晶体中的基本特性的记忆和理解，包括位错名称、Burgers矢量、位错性质、形成方法和运动状态等基础概念。这些内容属于材料科学中位错理论的基础知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生记忆并理解Frank partial dislocations的多个关键特征，包括名称、Burgers向量、位错性质、形成方法和运动状态。虽然涉及多个知识点，但都属于基础概念记忆范畴，不需要复杂的分析或比较。因此，在选择题型内属于中等难度（等级2）。", "convertible": true, "correct_option": "Frank partial dislocation; Burgers vector is 1/3 <111>; the nature of the dislocation is edge-type; the formation method involves inserting or removing a layer of {111} close-packed plane in a local region of the crystal; the motion state is that it can only climb, not glide.", "choice_question": "Which of the following correctly describes the main characteristics of Frank partial dislocations in FCC crystals?", "conversion_reason": "The answer is a standard and concise description of the characteristics of Frank partial dislocations, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description among several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Frank partial dislocation; Burgers vector is 1/3 <111>; edge-type; formed by inserting/removing {111} plane; can only climb", "B": "Frank partial dislocation; Burgers vector is 1/6 <112>; mixed-type; formed by shear deformation; can glide on {111} plane", "C": "Shockley partial dislocation; Burgers vector is 1/3 <111>; screw-type; formed by atomic vacancy condensation; can cross-slip", "D": "Frank-Read dislocation; Burgers vector is 1/2 <110>; edge-type; formed by plastic deformation; can both glide and climb" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes all key characteristics of Frank partial dislocations in FCC crystals. Option B incorrectly uses Shockley partial's Burgers vector and glide capability. Option C confuses Frank with Shockley partial and screw-type nature. Option D introduces non-existent 'Frank-Read' dislocation while mixing perfect dislocation characteristics. The traps exploit: 1) confusion between Frank/Shockley partials (B,C), 2) Burgers vector magnitude similarity (C), 3) dislocation type misassignment (C), and 4) fabricated dislocation names (D).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3133, "question": "Explain the basic concept and terminology: Dynamic recovery", "answer": "Dynamic recovery: During hot deformation of high stacking fault energy metallic materials, due to the narrow width of extended dislocations, they are prone to constriction and cross-slip. Therefore, high-temperature recovery occurs simultaneously during hot deformation, hence it is called dynamic recovery. It is the primary or sole softening mechanism for high stacking fault energy metallic materials during hot deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释动态回复的基本概念和术语，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查动态恢复的基本概念和术语的定义，属于基础概念的记忆和理解范畴，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生不仅记忆动态恢复的基本定义，还需要理解其发生条件和作用机制。虽然不涉及复杂的概念体系阐述，但需要考生对相关术语和原理有一定的掌握和解释能力，属于概念解释和描述的难度层次。", "convertible": true, "correct_option": "Dynamic recovery: During hot deformation of high stacking fault energy metallic materials, due to the narrow width of extended dislocations, they are prone to constriction and cross-slip. Therefore, high-temperature recovery occurs simultaneously during hot deformation, hence it is called dynamic recovery. It is the primary or sole softening mechanism for high stacking fault energy metallic materials during hot deformation.", "choice_question": "Which of the following correctly describes the concept of dynamic recovery?", "conversion_reason": "The answer is a standard definition of a scientific concept, which can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dynamic recovery is the primary softening mechanism for high stacking fault energy materials during hot deformation, occurring through dislocation cross-slip and annihilation.", "B": "Dynamic recovery refers to the spontaneous reduction of dislocation density in all crystalline materials upon cooling from high temperatures.", "C": "Dynamic recovery describes the transformation of dislocations into grain boundaries during plastic deformation at room temperature.", "D": "Dynamic recovery is the process where vacancies migrate to dislocations during quenching, reducing their mobility." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes dynamic recovery as the dominant softening mechanism in high stacking fault energy materials during hot deformation, where dislocations can cross-slip and annihilate. Option B is incorrect because it confuses dynamic recovery with static recovery that occurs during cooling. Option C is wrong as it mixes up dynamic recovery with dynamic recrystallization. Option D describes a quenching phenomenon unrelated to hot deformation processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3444, "question": "If Cr12MoV steel is selected to manufacture a stamping die with certain hot hardness requirements, what heat treatment process should be formulated? Why?", "answer": "When Cr12MoV steel is used to make a stamping die with certain hot hardness requirements, the secondary hardening method can be adopted, i.e., quenching at 1050～1100℃ followed by multiple tempering at 500-520℃, which can increase the hardness to 60～62HRC. Reason: The secondary hardening method of Cr12MoV steel is suitable for applications with higher working temperatures (400～500℃) or requiring hot hardness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述Cr12MoV钢的热处理工艺及其原因，答案提供了详细的工艺步骤和理论依据，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求针对特定材料（Cr12MoV钢）和特定应用场景（冲压模具的热硬度要求）制定热处理工艺，并解释原因。这需要综合运用材料科学知识，包括材料的热处理特性、二次硬化机理、温度选择对性能的影响等多方面知识，并进行推理分析。 | 难度: 在选择题型中，该题目属于最高难度等级。题目不仅要求考生掌握Cr12MoV钢的热处理工艺知识，还需要理解二次硬化法的机理及其在特定工况（热硬度要求）下的适用性。正确选项涉及高温淬火和多次回火的复杂工艺参数（1050～1100℃淬火+500-520℃回火），并需要解释该方法能提升热硬度的深层原因（碳化物析出强化）。这种综合工艺选择与机理解释的题目，远超简单记忆或单一概念判断，需要考生具备材料相变、合金元素作用和工程应用场景的综合分析能力，完全符合\"复杂现象全面分析\"的等级5标准。", "convertible": true, "correct_option": "The secondary hardening method can be adopted, i.e., quenching at 1050～1100℃ followed by multiple tempering at 500-520℃, which can increase the hardness to 60～62HRC.", "choice_question": "If Cr12MoV steel is selected to manufacture a stamping die with certain hot hardness requirements, what heat treatment process should be formulated?", "conversion_reason": "The answer is a standard procedure and can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Quenching at 1050～1100℃ followed by multiple tempering at 500-520℃", "B": "Normalizing at 850℃ followed by single tempering at 200℃", "C": "Austempering at 300℃ to achieve bainitic microstructure", "D": "Solution treatment at 1200℃ followed by water quenching" }, "correct_answer": "A", "explanation": "The correct answer utilizes the secondary hardening phenomenon specific to high-alloy tool steels like Cr12MoV, where high-temperature tempering precipitates fine alloy carbides. Option B is a cognitive bias trap - using standard tempering temperatures that would fail to achieve required hardness. Option C exploits professional intuition by suggesting bainite formation which is inappropriate for stamping dies. Option D is a multi-level verification trap - while solution treatment is valid for some steels, it would cause excessive grain growth in Cr12MoV.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1680, "question": "Compare the electronegativity of Ca and Mg, and determine whether CaO-MgO meets the electronegativity condition for forming a solid solution. (The electronegativity of Ca is 1.0, and that of Mg is 1.2)", "answer": "The electronegativity of Ca is 1.0, and that of Mg is 1.2. Their electronegativity values are close and within the same period, meeting the electronegativity condition for forming a solid solution.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求比较Ca和Mg的电负性，并判断CaO-MgO是否符合形成固溶体的电负性条件。答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求比较两种元素的电负性并判断是否符合形成固溶体的条件，涉及基本概念的应用和简单判断，不需要复杂的分析或多步计算。 | 难度: 在选择题型中，该题目属于简单应用层次，主要考察对电负性基本概念的理解和简单比较。题目提供了明确的电负性数值，只需进行直接比较和判断是否符合固溶体形成的电负性条件，无需复杂计算或多步骤推理。属于选择题中较为基础的难度水平。", "convertible": true, "correct_option": "Their electronegativity values are close and within the same period, meeting the electronegativity condition for forming a solid solution.", "choice_question": "Compare the electronegativity of Ca and Mg, and determine whether CaO-MgO meets the electronegativity condition for forming a solid solution. (The electronegativity of Ca is 1.0, and that of Mg is 1.2)", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Their electronegativity difference (0.2) is within the 0.4 threshold, allowing solid solution formation", "B": "The ionic radius mismatch (Ca2+ 1.00Å vs Mg2+ 0.72Å) prevents solid solution despite electronegativity similarity", "C": "The large difference in melting points (CaO 2572°C vs MgO 2852°C) dominates over electronegativity considerations", "D": "Their positions in different groups (IIA vs IIB) create electronic structure incompatibility" }, "correct_answer": "A", "explanation": "Correct answer A follows the Hume-Rothery rule that electronegativity differences <0.4 support solid solution formation. Option B exploits the common misconception that ionic radius is the sole determinant (while <15% mismatch is acceptable here). Option C uses a physically real but irrelevant property (melting points don't affect solid solution criteria). Option D misapplies periodic table grouping logic (both are group 2 elements).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4524, "question": "A large-particle composite consisting of tungsten particles within a copper matrix is to be prepared. If the volume fractions of tungsten and copper are 0.60 and 0.40 , respectively, estimate the upper limit for the specific stiffness of this composite given the data that follow.\n\\begin{tabular}{lcc}\n\\hline & Specific Gravity & \\begin{tabular}{c} \nModulus of Elasticity \\\\\n(GPa)\n\\end{tabular} \\\\\n\\hline Copper & 8.9 & 110 \\\\\nTungsten & 19.3 & 407 \\\\\n\\hline\n\\end{tabular}", "answer": "the upper limit for the specific stiffness of this composite is 19.0 \\text{ gpa}. an alternate approach yields a specific stiffness of 17.6 \\text{ gpa}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的体积分数和材料属性数据进行数值计算，以估计复合材料的具体刚度上限。解答过程需要应用公式和进行数值运算，最终给出具体的数值结果。答案的形式也是具体的数值，符合计算题的特征。 | 知识层次: 题目需要应用复合材料力学性能的混合法则（rule of mixtures）进行多步计算，涉及体积分数、弹性模量和比重的综合运用，需要概念关联和综合分析能力。虽然计算过程不涉及复杂的推理或创新设计，但超出了简单套用公式的层次。 | 难度: 在选择题中属于中等偏上难度，需要理解复合材料的概念，掌握比刚度的计算方法，并进行多步计算。题目涉及体积分数、比重的转换以及弹性模量的综合运用，虽然选项给出了计算结果，但需要考生具备较强的综合分析能力才能正确理解和选择。", "convertible": true, "correct_option": "19.0 GPa", "choice_question": "A large-particle composite consisting of tungsten particles within a copper matrix is prepared with volume fractions of tungsten and copper as 0.60 and 0.40, respectively. Using the given data, what is the upper limit for the specific stiffness of this composite?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "19.0 GPa", "B": "24.8 GPa", "C": "15.6 GPa", "D": "32.7 GPa" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the rule of mixtures for the upper bound of elastic modulus (E_c = V_tungsten*E_tungsten + V_copper*E_copper = 0.6*407 + 0.4*110 = 288.2 GPa) divided by the composite density (ρ_c = V_tungsten*ρ_tungsten + V_copper*ρ_copper = 0.6*19.3 + 0.4*8.9 = 15.14 g/cm³), giving 288.2/15.14 = 19.0 GPa. Option B incorrectly uses the harmonic mean for modulus calculation. Option C mistakenly swaps the volume fractions. Option D erroneously uses the tungsten's specific gravity as the composite density.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 443, "question": "The yield strength σs of crystalline materials changes with the variation of the tensile axis relative to the crystal orientation.", "answer": "(√)", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（The yield strength σs of crystalline materials changes with the variation of the tensile axis relative to the crystal orientation），并要求判断其正确性（答案给出√表示正确）。这符合判断题的特征，即判断陈述的对错。 | 知识层次: 题目考查的是晶体材料屈服强度与拉伸轴相对于晶体取向变化的基本概念，属于基础概念的记忆和理解范畴。 | 难度: 该题目属于基础概念正误判断题，仅需记忆晶体材料屈服强度与拉伸轴方向关系的基本原理即可作答，无需深入理解或分析复杂概念。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "(√)", "choice_question": "The yield strength σs of crystalline materials changes with the variation of the tensile axis relative to the crystal orientation.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials exhibit isotropic mechanical properties regardless of processing history.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While amorphous materials generally show more isotropic behavior than crystalline materials, their mechanical properties can still be affected by processing-induced anisotropy (e.g., thermal stresses during cooling or mechanical alignment during fabrication). The absolute term 'all' makes this statement incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4329, "question": "Consider 1.0 kg of austenite containing 1.15 wt % C, cooled to below 727 C (1341 F). What is the proeutectoid phase?", "answer": "the proeutectoid phase is fe3c.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来确定先共析相（proeutectoid phase），答案是一个具体的相名称（Fe3C），而不是从多个选项中选择或进行数值计算。 | 知识层次: 题目需要理解铁碳相图的基本原理，并能够根据给定的碳含量和冷却条件判断出先共析相。这涉及到对相图的分析和应用，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。该题目涉及的知识点包括相图分析、碳含量计算和相变过程判断，需要学生综合运用这些知识来解答。虽然题目给出了具体的碳含量和温度条件，但仍需进行多步计算和概念关联才能确定正确的先共析相。", "convertible": true, "correct_option": "Fe3C", "choice_question": "Consider 1.0 kg of austenite containing 1.15 wt % C, cooled to below 727 C (1341 F). What is the proeutectoid phase?", "conversion_reason": "The answer is a standard term (Fe3C), which can be presented as a single correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fe3C", "B": "α-ferrite", "C": "Pearlite", "D": "Martensite" }, "correct_answer": "A", "explanation": "The correct answer is Fe3C (cementite) because at 1.15 wt% C (hyper-eutectoid composition), the proeutectoid phase that forms upon cooling below 727°C is cementite. Option B (α-ferrite) is a strong distractor as it's the proeutectoid phase for hypo-eutectoid steels, playing on the common confusion between hyper/hypo cases. Option C (Pearlite) is incorrect but tempting as it forms at the eutectoid reaction. Option D (Martensite) exploits the AI's tendency to associate rapid cooling phases with carbon steels, though this requires quenching not slow cooling.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1473, "question": "In essence, a twin is also a stacking fault", "answer": "Correct", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（Correct），符合判断题的特征 | 知识层次: 题目考查对孪晶和堆垛层错这两个基础概念的理解和记忆，属于材料科学中的基本概念辨析 | 难度: 该题目属于基础概念记忆层次，仅需判断\"孪晶也是一种堆垛层错\"这一陈述的正误。在选择题型中，这种直接考察定义或分类记忆的题目属于最基本的难度等级（等级1），不需要复杂的理解或分析过程。", "convertible": true, "correct_option": "Correct", "choice_question": "In essence, a twin is also a stacking fault", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials exhibit a glass transition temperature when heated.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most amorphous materials do show a glass transition, some cross-linked polymers or heavily constrained systems may not exhibit a clear Tg due to restricted molecular mobility. This statement uses an absolute term 'all' which creates a precision trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3682, "question": "The diffusion coefficient for Cr+3 in Cr2O3 is 6x10^-15 cm^2/s at 727C and is 1x10^-9 cm^2/s at 1400C. Calculate the activation energy q.", "answer": "the activation energy q is 59,230 cal/mol.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的扩散系数和温度数据，使用阿伦尼乌斯方程计算活化能q，需要数值计算和公式应用。答案是一个具体的数值结果（59,230 cal/mol），符合计算题的特征。 | 知识层次: 题目需要应用阿伦尼乌斯方程进行多步计算，涉及对数运算和温度转换，需要理解扩散系数与温度的关系，并正确关联公式中的参数。虽然计算过程较为直接，但需要综合运用多个概念并进行适当的数学处理。 | 难度: 在选择题中属于中等难度，需要理解扩散系数与温度的关系（阿伦尼乌斯方程），并进行多步计算来求解活化能。虽然题目提供了必要的数据，但需要考生正确应用对数运算和单位转换，属于综合性计算问题。", "convertible": true, "correct_option": "59,230 cal/mol", "choice_question": "The diffusion coefficient for Cr+3 in Cr2O3 is 6x10^-15 cm^2/s at 727C and is 1x10^-9 cm^2/s at 1400C. The activation energy q is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "59,230 cal/mol", "B": "48,500 cal/mol", "C": "72,100 cal/mol", "D": "63,800 cal/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (59,230 cal/mol) calculated using the Arrhenius equation for diffusion coefficients at two temperatures. Option B (48,500 cal/mol) is designed to exploit the common mistake of using incorrect temperature units (Kelvin vs Celsius). Option C (72,100 cal/mol) targets the error of misapplying the natural logarithm conversion. Option D (63,800 cal/mol) is a close numerical trap for those who make minor calculation errors in the activation energy derivation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4476, "question": "Compute repeat unit molecular weight for poly(vinyl chloride)", "answer": "62.49g/mol", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算聚氯乙烯重复单元的分子量，需要通过数值计算和公式应用来得出具体数值结果62.49g/mol，符合计算题的特征。 | 知识层次: 题目要求计算聚氯乙烯重复单元的分子量，这属于基本公式的直接应用，只需理解重复单元的概念和进行简单的原子量相加计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于最低难度等级。题目仅要求直接套用重复单元分子量的基本计算公式（即氯乙烯单体的分子量计算），无需任何额外的概念理解或步骤组合。正确选项62.49g/mol可通过简单查阅氯乙烯的原子组成（C2H3Cl）并相加标准原子量直接得出，完全符合\"单一公式直接计算\"的标准。选择题型进一步降低了难度，因为考生只需识别正确计算结果而非自行推导。", "convertible": true, "correct_option": "62.49g/mol", "choice_question": "What is the repeat unit molecular weight for poly(vinyl chloride)?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "62.49 g/mol", "B": "64.47 g/mol", "C": "58.44 g/mol", "D": "60.05 g/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (62.49 g/mol) because the repeat unit of poly(vinyl chloride) is -[CH2-CHCl]- with molecular weights: C=12.01, H=1.01, Cl=35.45 (12.01 + 1.01 + 12.01 + 1.01 + 35.45 + 1.01 = 62.49). Option B (64.47 g/mol) is a common error from counting hydrogen atoms incorrectly. Option C (58.44 g/mol) mimics the molecular weight of NaCl to exploit material science association bias. Option D (60.05 g/mol) is derived from omitting the chlorine atom, targeting AI's tendency to overlook heavy atoms in polymer calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 974, "question": "How does the third component affect binary diffusion?", "answer": "The third component can have different effects on binary diffusion, such as Mo and W reducing the diffusion coefficient of C in γ-Fe; Co and Si accelerating the diffusion of C; Mn and Ni having little effect.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释第三组分对二元扩散的影响，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求解释第三组分对二元扩散的影响，并列举了不同元素的具体作用。这需要综合运用扩散理论、理解不同元素在材料中的行为，并进行机理上的解释。涉及多个概念的关联和综合分析，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The third component can have different effects on binary diffusion, such as Mo and W reducing the diffusion coefficient of C in γ-Fe; Co and Si accelerating the diffusion of C; Mn and Ni having little effect.", "choice_question": "How does the third component affect binary diffusion?", "conversion_reason": "The answer is a detailed explanation that can be directly used as the correct option in a multiple-choice question. The original question can remain unchanged as it is already suitable for a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The third component can either increase or decrease the binary diffusion coefficient depending on its interaction with the diffusing species", "B": "The third component always reduces the binary diffusion coefficient due to increased atomic packing density", "C": "The third component has negligible effect as diffusion primarily depends on the binary pair interaction", "D": "The third component always accelerates binary diffusion by creating additional vacancy sites" }, "correct_answer": "A", "explanation": "The correct answer is A because the effect of a third component on binary diffusion is complex and can vary based on specific atomic interactions. Option B exploits the cognitive bias that additional elements always reduce diffusion by increasing packing density, while in reality some elements like Co and Si can accelerate diffusion. Option C is a professional intuition trap, appealing to the common assumption that binary interactions dominate, while ignoring well-documented ternary effects. Option D creates a multi-level verification trap by correctly noting vacancy mechanisms but incorrectly asserting an always-accelerating effect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3465, "question": "What is the difference between the purpose of quenching for austenitic stainless steel and wear-resistant steel compared to that of general steel?", "answer": "The purpose of quenching for austenitic stainless steel and wear-resistant steel is to obtain a single-phase, uniform austenitic structure, preventing the formation of secondary phases that could cause intergranular corrosion. Therefore, the quenching of austenitic stainless steel is referred to as solution treatment, while for wear-resistant steel, the quenching process, which results in a single austenitic structure with high plasticity and toughness, is also known as water toughening treatment.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释淬火对奥氏体不锈钢和耐磨钢与普通钢的不同目的，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解不同钢材淬火目的的区别，并解释其背后的原理和术语（如固溶处理和水韧处理），涉及多个概念的关联和综合分析，但不需要复杂的推理或创新设计。 | 难度: 在选择题型中，该题目需要考生理解并比较不同钢材（奥氏体不锈钢、耐磨钢和普通钢）淬火目的的区别，涉及多个专业概念（单相奥氏体组织、二次相、晶间腐蚀等）和热处理工艺（固溶处理、水韧处理）。解题时需要综合分析不同材料的热处理目的和机理，属于多角度分析论述的难度等级。", "convertible": true, "correct_option": "The purpose of quenching for austenitic stainless steel and wear-resistant steel is to obtain a single-phase, uniform austenitic structure, preventing the formation of secondary phases that could cause intergranular corrosion. Therefore, the quenching of austenitic stainless steel is referred to as solution treatment, while for wear-resistant steel, the quenching process, which results in a single austenitic structure with high plasticity and toughness, is also known as water toughening treatment.", "choice_question": "What is the difference between the purpose of quenching for austenitic stainless steel and wear-resistant steel compared to that of general steel?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solution treatment to prevent intergranular corrosion by maintaining single-phase austenite", "B": "To increase hardness through rapid cooling and martensite formation", "C": "To refine grain size and improve overall mechanical properties", "D": "To relieve internal stresses caused by prior cold working processes" }, "correct_answer": "A", "explanation": "The correct answer is A because quenching for austenitic stainless steel and wear-resistant steel aims to maintain a single-phase austenitic structure to prevent intergranular corrosion (solution treatment), not to form martensite. Option B is a cognitive bias trap exploiting the common association of quenching with martensite formation in general steels. Option C is a professional intuition trap suggesting grain refinement which is incorrect for these materials. Option D is a multi-level verification trap mixing stress relief with the actual purpose of solution treatment.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 220, "question": "What are the factors affecting the plasticity of clay?", "answer": "The influencing factors include: 1. Mineral composition, different mineral compositions result in varying interparticle forces. 2. Types of adsorbed cations, higher valence cations improve plasticity. 3. Particle size and shape, finer particles with larger specific surface area and more contact points between particles increase plasticity. 4. Water content, etc.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释影响粘土塑性的因素，答案以文字论述形式给出，列举了多个影响因素并进行简要说明，符合简答题的特征。 | 知识层次: 题目考查对影响粘土塑性因素的基本概念记忆和理解，包括矿物组成、吸附阳离子类型、颗粒大小和形状以及含水量等基础知识点，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个影响粘土塑性的因素，但每个因素的解释相对直接，主要基于基础概念的记忆和理解。正确选项提供了清晰的分类和简要解释，不需要复杂的分析或推理步骤。因此，它属于等级2，即概念解释和描述的难度水平。", "convertible": true, "correct_option": "Mineral composition, types of adsorbed cations, particle size and shape, and water content", "choice_question": "Which of the following are factors affecting the plasticity of clay?", "conversion_reason": "The answer provided is a list of standard factors affecting the plasticity of clay, which can be converted into a multiple-choice question format by presenting these factors as options and asking the examinee to select the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Mineral composition and water content", "B": "Crystalline structure and elastic modulus", "C": "Thermal conductivity and specific heat capacity", "D": "Surface tension and dielectric constant" }, "correct_answer": "A", "explanation": "The correct answer is A because mineral composition directly affects the clay's chemical behavior and water content determines the mobility of clay particles, both being fundamental to plasticity. Option B uses crystalline structure (which affects mechanical properties but not plasticity) and elastic modulus (a bulk property unrelated to plastic deformation). Option C introduces thermal properties which are irrelevant to plasticity. Option D uses surface tension (a liquid property) and dielectric constant (an electrical property), creating a cross-domain confusion trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1608, "question": "7．The main resistances to solid-state phase transformation are (19) and (20)", "answer": "(19) interfacial energy; (20) elastic strain energy", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个主要的固态相变阻力，答案需要提供具体的术语（界面能和弹性应变能），属于简答题类型，需要文字解释和论述。 | 知识层次: 题目考查对固态相变主要阻力的基本概念记忆，即界面能和弹性应变能，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目要求填写固态相变的主要阻力，正确选项直接给出了两个基础概念（界面能和弹性应变能），无需复杂推理或概念间的比较分析。这属于对基础概念记忆的直接考察，符合等级1的标准。", "convertible": true, "correct_option": "interfacial energy and elastic strain energy", "choice_question": "The main resistances to solid-state phase transformation are:", "conversion_reason": "The answer is a standard terminology and can be converted into a multiple-choice format by providing options including the correct terms.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interfacial energy and elastic strain energy", "B": "Activation energy and lattice vibration energy", "C": "Surface tension and dislocation density", "D": "Gibbs free energy difference and stacking fault energy" }, "correct_answer": "A", "explanation": "The correct answer is A because interfacial energy arises from the creation of new phase boundaries, and elastic strain energy results from lattice mismatch during transformation. Option B is misleading as activation energy is a kinetic barrier, not a resistance, and lattice vibration is unrelated. Option C exploits surface tension's similarity to interfacial energy but adds irrelevant dislocation density. Option D uses thermodynamic (Gibbs) and defect (stacking fault) terms that sound plausible but don't represent transformation resistances.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1432, "question": "What is the most densely packed direction in a body-centered cubic crystal?", "answer": "<111>", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答最密排方向的具体指数，需要专业知识解释和论述，答案形式为晶体学方向指数而非简单选择或判断 | 知识层次: 题目考查对体心立方晶体中最密排方向的基本概念的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目直接考查对体心立方晶体最密排方向的记忆，正确选项<111>是晶体学中的基础知识点，不需要任何解释或分析步骤。学生只需记住这个基本概念即可作答，符合选择题型中最简单的难度等级。", "convertible": true, "correct_option": "<111>", "choice_question": "What is the most densely packed direction in a body-centered cubic crystal?", "conversion_reason": "The answer is a standard crystallographic direction notation, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "<111>", "B": "<100>", "C": "<110>", "D": "<112>" }, "correct_answer": "A", "explanation": "The <111> direction is correct because in BCC crystals, atoms are most closely packed along the body diagonal. Option B (<100>) exploits the face-centered cubic intuition bias. Option C (<110>) is a trap for those confusing BCC with FCC structures where <110> is indeed the close-packed direction. Option D (<112>) uses a less common direction that might seem plausible due to its intermediate index values.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 955, "question": "Briefly describe the meaning of discontinuous precipitation", "answer": "Discontinuous precipitation: also known as cellular precipitation, where an interface exists between the parent phase and the newly formed α phase. Across this interface, the parent phase discontinuously changes from supersaturated to saturated state, and the lattice parameter also changes discontinuously.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述不连续沉淀的含义，答案以文字解释和论述的形式给出，符合简答题的特征。 | 知识层次: 题目考查对discontinuous precipitation这一基本概念的定义和特征的理解，属于基础概念记忆范畴，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆，但要求考生不仅知道\"discontinuous precipitation\"这个术语，还需要理解其作为\"cellular precipitation\"的别称，以及能够描述相界面的特征和变化过程。这超出了简单的定义复述（等级1），但尚未达到需要阐述复杂概念体系的程度（等级3）。题目要求考生对相变过程有一定理解，但选项本身提供了完整的解释框架。", "convertible": true, "correct_option": "Discontinuous precipitation: also known as cellular precipitation, where an interface exists between the parent phase and the newly formed α phase. Across this interface, the parent phase discontinuously changes from supersaturated to saturated state, and the lattice parameter also changes discontinuously.", "choice_question": "Which of the following best describes discontinuous precipitation?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the best description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A phase transformation where solute atoms diffuse along grain boundaries forming distinct precipitate cells with sharp interfaces", "B": "A continuous precipitation process where solute atoms uniformly distribute throughout the matrix without distinct phase boundaries", "C": "A spinodal decomposition mechanism resulting in compositionally modulated structures without nucleation", "D": "A precipitation process where solute atoms cluster randomly without any specific orientation relationship to the matrix" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes discontinuous precipitation's key feature of forming distinct cells with sharp interfaces. Option B is a cognitive bias trap, confusing it with continuous precipitation. Option C exploits professional intuition by referencing another diffusion-based transformation. Option D creates a multi-level verification trap by mixing elements of homogeneous nucleation theory.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1732, "question": "Explain which locations are likely to be the preferred nucleation sites for recrystallization", "answer": "The preferred nucleation sites are: original grain boundaries, newly formed high-angle grain boundaries during deformation or gradually formed high-angle grain boundaries through subgrain growth, and the vicinity of second-phase particles.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释再结晶的优先形核位置，答案需要文字解释和论述，没有提供选项或要求计算 | 知识层次: 题目要求解释再结晶过程中优先形核的位置，涉及对变形过程中晶界演变、亚晶生长和第二相粒子影响的理解。需要将多个概念关联起来进行综合分析，但不需要进行复杂的推理或创新应用。 | 难度: 在选择题型中，该题目属于较高难度。正确选项涉及多个关键概念的综合分析，包括原始晶界、变形过程中新形成的高角度晶界、亚晶生长逐渐形成的高角度晶界以及第二相粒子附近的成核位置。考生需要理解这些不同位置的成核机制及其相互关系，并能将这些概念关联起来进行多角度分析。此外，题目要求的知识层次为中等应用，涉及多步计算和概念关联，进一步增加了题目的复杂程度。因此，在选择题型内，该题目属于等级4的难度。", "convertible": true, "correct_option": "original grain boundaries, newly formed high-angle grain boundaries during deformation or gradually formed high-angle grain boundaries through subgrain growth, and the vicinity of second-phase particles", "choice_question": "Which of the following are likely to be the preferred nucleation sites for recrystallization?", "conversion_reason": "The answer is a standard list of specific locations, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "original grain boundaries and high-angle grain boundaries formed during deformation", "B": "low-angle grain boundaries and twin boundaries", "C": "single crystal regions with minimal dislocation density", "D": "regions with maximum stored energy but no pre-existing boundaries" }, "correct_answer": "A", "explanation": "The correct answer is A because recrystallization preferentially nucleates at high-energy sites like original grain boundaries and newly formed high-angle boundaries during deformation. Option B is incorrect because low-angle boundaries and twins are not effective nucleation sites due to their lower energy. Option C exploits the cognitive bias that defect-free regions might be favorable, but actually lack the necessary driving force. Option D uses the intuitive but incorrect assumption that maximum stored energy alone is sufficient, ignoring the need for structural inhomogeneity.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 546, "question": "2. In face-centered cubic packing, the number of atoms in the unit cell is (5), it has (6) _ tetrahedral voids, (7) _ octahedral voids.", "answer": "(5) 4; (6) 8; (7) 4", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的数值答案，而不是从选项中选择或判断对错，也不需要复杂的计算过程，属于简答题类型。 | 知识层次: 题目考查面心立方堆积中原子数、四面体空隙和八面体空隙的基本概念记忆，属于晶体结构的基础知识，不需要复杂的计算或分析。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目直接考察面心立方堆积中原子数、四面体空隙和八面体空隙的数量，这些都是晶体学中最基础的定义性知识，无需复杂推理或概念关联。学生只需记忆单位细胞内原子数（4）、四面体空隙数（8）和八面体空隙数（4）这三个固定数值即可作答，属于纯记忆性知识点。选择题型中此类仅需机械回忆的题目通常列为最低难度等级。", "convertible": true, "correct_option": "(5) 4; (6) 8; (7) 4", "choice_question": "In face-centered cubic packing, the number of atoms in the unit cell is (5), it has (6) _ tetrahedral voids, (7) _ octahedral voids.", "conversion_reason": "The answer is a standard and specific combination of numbers, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4 atoms, 8 tetrahedral voids, 4 octahedral voids", "B": "4 atoms, 4 tetrahedral voids, 8 octahedral voids", "C": "8 atoms, 8 tetrahedral voids, 4 octahedral voids", "D": "8 atoms, 4 tetrahedral voids, 8 octahedral voids" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC packing, each unit cell contains 4 atoms (1 corner atom × 8 corners × 1/8 contribution + 6 face-centered atoms × 1/2 contribution). The number of tetrahedral voids is always double the number of atoms (8), while octahedral voids equal the number of atoms (4). Option B swaps the void counts, exploiting the common confusion between void types. Option C doubles the atom count by ignoring fractional contributions, a typical calculation error. Option D combines both mistakes, making it appealing to those who misremember both atom count and void ratios.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 531, "question": "5. When Ca0 is doped into ZrO2, where Ca2+ ions replace Zr4+ ions, due to the requirement of electrical neutrality, this substitution simultaneously creates a (9) defect, which can be represented by the (10) defect reaction equation.", "answer": "(9) vacancy; (10) CaO→ZrO2CaZr′′+V0..+ O0", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求填写空缺部分并写出缺陷反应方程，需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目要求理解掺杂过程中的电荷平衡原理，并写出缺陷反应方程，涉及多步概念关联和综合分析，需要将基础概念应用到具体情境中。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及掺杂缺陷的形成和电荷平衡，需要考生掌握离子取代对晶体结构的影响以及缺陷反应方程的书写。虽然题目提供了正确选项，但考生仍需具备一定的材料科学基础，能够将Ca2+取代Zr4+的电荷补偿机制与氧空位的形成联系起来，并正确理解缺陷反应方程的含义。这需要中等层次的应用能力，包括多步计算、概念关联和综合分析。", "convertible": true, "correct_option": "vacancy; CaO→ZrO2CaZr′′+V0..+ O0", "choice_question": "When Ca0 is doped into ZrO2, where Ca2+ ions replace Zr4+ ions, due to the requirement of electrical neutrality, this substitution simultaneously creates a (9) defect, which can be represented by the (10) defect reaction equation. Which of the following correctly fills in (9) and (10)?", "conversion_reason": "The answer is a standard terminology and a specific defect reaction equation, which can be presented as options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "vacancy; CaO→ZrO2CaZr′′+V0..+ O0", "B": "interstitial; CaO→ZrO2CaZr′′+Oi..", "C": "vacancy; CaO→ZrO2CaZr′′+VO..+ O0", "D": "interstitial; CaO→ZrO2CaZr′′+VZr....+ O0" }, "correct_answer": "A", "explanation": "The correct answer is A because the substitution of Ca2+ for Zr4+ creates oxygen vacancies (V0..) to maintain charge neutrality, as represented by the defect reaction equation. Option B incorrectly suggests interstitial oxygen defects. Option C uses incorrect notation for oxygen vacancies. Option D introduces an implausible zirconium vacancy defect. The key challenge is distinguishing between the correct Kroger-Vink notation and plausible but incorrect defect types.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2201, "question": "Based on the minimum recrystallization temperature of iron, 723 K, select the recrystallization annealing temperature for iron", "answer": "The recrystallization annealing temperature for iron T=823∼923 K", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求基于给定的最低再结晶温度选择一个合适的再结晶退火温度范围，答案给出了具体的温度范围，属于需要文字解释和论述的简答题类型 | 知识层次: 题目要求基于已知的最低再结晶温度（723 K）选择铁的再结晶退火温度，这属于直接应用基本公式或经验规则（通常在最低再结晶温度以上100-200 K）来确定具体参数。虽然需要理解再结晶温度的概念，但主要考察的是简单应用能力，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接套用已知的最低再结晶温度（723 K）并选择适当的再结晶退火温度范围（823∼923 K）。题目不涉及复杂计算或多步骤推理，仅需基本知识点的记忆和应用，因此难度较低。", "convertible": true, "correct_option": "T=823∼923 K", "choice_question": "Based on the minimum recrystallization temperature of iron, 723 K, select the recrystallization annealing temperature for iron:", "conversion_reason": "The answer is a specific temperature range, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "T=823∼923 K", "B": "T=723 K", "C": "T=1023∼1123 K", "D": "T=623 K" }, "correct_answer": "A", "explanation": "The correct answer is A because recrystallization annealing temperature is typically 100-200°C above the minimum recrystallization temperature (723 K for iron). Option B is a cognitive bias trap - while 723 K is the minimum recrystallization temperature, annealing requires higher temperatures. Option C exploits professional intuition by suggesting excessively high temperatures that would cause grain growth. Option D uses a common misconception that annealing occurs below recrystallization temperature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1182, "question": "Ferritic stainless steel is (27)", "answer": "(27) 1Cr17", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个具体的材料牌号（1Cr17），属于需要简短文字回答的形式，没有提供选项或需要判断对错，也不涉及计算过程。 | 知识层次: 题目考查对铁素体不锈钢基本分类的记忆，仅需回答特定牌号1Cr17，属于基础概念记忆性知识。 | 难度: 该题目属于基础概念记忆类型，仅需识别Ferritic stainless steel的正确选项1Cr17，无需复杂推理或概念比较。在选择题型中，此类直接考察定义和分类的记忆性知识属于最低难度等级。", "convertible": true, "correct_option": "1Cr17", "choice_question": "Ferritic stainless steel is:", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1Cr17", "B": "304", "C": "316L", "D": "430F" }, "correct_answer": "A", "explanation": "1Cr17是典型的铁素体不锈钢，其铬含量为17%且不含镍，符合铁素体不锈钢的基本特征。304和316L是奥氏体不锈钢，利用常见不锈钢牌号制造认知混淆。430F虽然属于铁素体系列，但含硫量高属于易切削钢，利用专业细分领域知识制造陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2904, "question": "Explain why crystal structures do not possess 5-fold or higher than 6-fold symmetry axes?", "answer": "5-fold or higher than 6-fold symmetry axes cannot satisfy the condition of identical surroundings around lattice points, lack translational symmetry, and thus cannot achieve a regularly periodic arrangement of crystal structures.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释晶体结构为何不具备5重或高于6重的对称轴，答案需要文字解释和论述，而非选择、判断或计算。 | 知识层次: 题目要求解释晶体结构中不存在5重或高于6重对称轴的原因，这需要综合运用晶体学的基本原理（如平移对称性、点阵理论）进行推理分析，并解释其物理机制。这超出了简单记忆或直接应用的范畴，属于对晶体对称性深层次理解的复杂分析。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求解释晶体结构中不存在5重或高于6重对称轴的原因，涉及对晶体学基本原理的深入理解，包括点阵的平移对称性和周期性排列的限制条件。正确选项不仅需要识别对称性限制，还需综合运用晶体学知识进行机理解释，这要求考生具备较高的分析推理能力和对复杂现象的全面理解。在选择题型中，此类题目通常需要考生超越简单记忆，进行深层次的概念整合和逻辑推理，因此难度等级为5。", "convertible": true, "correct_option": "5-fold or higher than 6-fold symmetry axes cannot satisfy the condition of identical surroundings around lattice points, lack translational symmetry, and thus cannot achieve a regularly periodic arrangement of crystal structures.", "choice_question": "Why do crystal structures not possess 5-fold or higher than 6-fold symmetry axes?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5-fold symmetry violates the crystallographic restriction theorem by creating gaps in the lattice", "B": "Higher symmetries require atomic vibrations that disrupt crystal stability", "C": "The Born-von Karman boundary conditions prohibit such symmetries in periodic structures", "D": "These symmetries would require impossible bond angles in close-packed structures" }, "correct_answer": "A", "explanation": "Correct answer A directly addresses the mathematical impossibility of 5-fold symmetry in periodic lattices. Option B exploits the common misconception that thermal vibrations could be the limiting factor. Option C misapplies boundary condition theory to symmetry restrictions. Option D creates confusion by mixing valid close-packing arguments with incorrect symmetry constraints.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4811, "question": "Give the approximate temperature at which creep deformation becomes an important consideration for zinc.", "answer": "for zn, 4°c or 39°f.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从选项中选择或判断对错，也不需要复杂的计算过程。答案是一个简短的具体数值，符合简答题的特征。 | 知识层次: 题目考查对锌材料蠕变变形温度这一基本概念的记忆，不需要复杂的应用或分析，仅需记住特定数值即可回答。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需要考生记住锌的蠕变变形温度这一具体数值即可。题目不涉及复杂的概念解释或分析过程，属于最简单的记忆性知识考察。", "convertible": true, "correct_option": "4°C or 39°F", "choice_question": "At approximately what temperature does creep deformation become an important consideration for zinc?", "conversion_reason": "The answer is a specific temperature range, which can be presented as a choice among other plausible but incorrect temperature ranges.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4°C (39°F)", "B": "150°C (302°F)", "C": "0.4 x melting temperature (≈120°C)", "D": "Recrystallization temperature (≈50°C)" }, "correct_answer": "A", "explanation": "正确答案A基于锌的低温蠕变特性，其同素异构转变温度约为4°C。干扰项B利用常见金属蠕变温度认知偏差；C采用看似科学的熔点比例法但忽略了锌的特殊性；D通过混淆再结晶与蠕变机制制造陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1047, "question": "Please indicate the methods and principles of refining metal grain size by increasing undercooling.", "answer": "Increase undercooling. Since the number of grains is directly proportional to the nucleation rate N and inversely proportional to the grain growth rate Vg, increasing N/Vg can refine the grains. Moreover, when undercooling is increased, although both N and Vg increase, the rate of increase in N is faster than that in Vg. Therefore, N/Vg increases with the increase in undercooling, meaning the grains become finer.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释增加过冷度细化金属晶粒的方法和原理，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释通过增加过冷度细化金属晶粒的方法和原理，涉及成核速率和晶粒生长速率的比较分析，需要综合运用材料科学中的相变理论，进行推理分析和机理解释。这超出了简单记忆或基本应用，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Increase undercooling. Since the number of grains is directly proportional to the nucleation rate N and inversely proportional to the grain growth rate Vg, increasing N/Vg can refine the grains. Moreover, when undercooling is increased, although both N and Vg increase, the rate of increase in N is faster than that in Vg. Therefore, N/Vg increases with the increase in undercooling, meaning the grains become finer.", "choice_question": "Which of the following methods and principles can refine metal grain size by increasing undercooling?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct method and principle.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increasing undercooling enhances both nucleation rate and growth rate, but nucleation rate dominates", "B": "Higher undercooling reduces atomic diffusion, suppressing grain growth", "C": "Undercooling creates more grain boundary defects that inhibit coarsening", "D": "The critical radius for nucleation decreases exponentially with undercooling" }, "correct_answer": "A", "explanation": "Correct answer A reflects the actual relationship where nucleation rate (N) increases faster than growth rate (Vg) with undercooling. B is incorrect because while diffusion decreases, it's not the primary refinement mechanism. C is a half-truth that traps by overemphasizing secondary effects. D contains a factual error (linear rather than exponential relationship) that exploits common mathematical misconceptions in nucleation theory.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 421, "question": "1.In the ionic crystal structure, the coordination number depends on the (3) of the positive and negative ions", "answer": "radius ratio", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（radius ratio）作为答案，而不是从多个选项中选择或进行判断/计算。这符合简答题的特征，即需要提供简短但具体的答案。 | 知识层次: 题目考查离子晶体结构中配位数与正负离子半径比的基本概念记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，此题属于基础概念记忆类题目，仅需回忆离子晶体结构中配位数与正负离子半径比的关系这一基本定义即可作答，无需复杂分析或概念整合。", "convertible": true, "correct_option": "radius ratio", "choice_question": "In the ionic crystal structure, the coordination number depends on the:", "conversion_reason": "The answer is a standard term (radius ratio), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "radius ratio", "B": "electronegativity difference", "C": "lattice energy", "D": "ionic charge magnitude" }, "correct_answer": "A", "explanation": "The coordination number in ionic crystals is primarily determined by the radius ratio of cations to anions, as this dictates how many anions can geometrically fit around a cation. Option B exploits the common misconception that electronegativity directly determines crystal structure. Option C uses lattice energy which is a consequence rather than determinant of coordination. Option D targets the intuitive but incorrect assumption that ionic charge controls coordination geometry.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 744, "question": "The basis for classifying silicate crystals is (6)", "answer": "[ $\\mathrm{Si}0{4}$ connection method", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释硅酸盐晶体分类的基础，需要文字描述和论述，答案给出了具体的分类依据（[ $\\mathrm{Si}0{4}$ connection method），属于简答题类型 | 知识层次: 题目考查对硅酸盐晶体分类基础的记忆和理解，主要涉及硅氧四面体连接方式这一基本概念，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目仅要求考生记忆并识别硅酸盐晶体分类的基础依据（$\\mathrm{Si}0_{4}$连接方式），无需解释或分析概念关系，属于最基础的概念记忆性知识，且选项直接指向核心定义，解题步骤简单明确。", "convertible": true, "correct_option": "Si0₄ connection method", "choice_question": "The basis for classifying silicate crystals is:", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Si0₄ connection method", "B": "Cation type in the silicate structure", "C": "Degree of polymerization of SiO₄ tetrahedra", "D": "Presence of non-bridging oxygen atoms" }, "correct_answer": "A", "explanation": "The correct answer is A because silicate crystal classification is fundamentally based on how the SiO₄ tetrahedra connect (isolated, chains, sheets, frameworks). Option B exploits the cognitive bias of focusing on cations which are important but not the classification basis. Option C uses a partially correct concept (polymerization) but is too broad. Option D targets the common misconception that non-bridging oxygen determines classification rather than being a secondary characteristic.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 845, "question": "Point out and explain the strict orientation relationship between the new phase and the parent phase in the characteristics of martensitic transformation", "answer": "The main orientation relationships between martensite and the parent phase are: 1 K·S relationship; 2 G-T relationship; 3 Nishiyama relationship.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出并解释马氏体相变中新相与母相之间的严格取向关系，答案提供了具体的取向关系名称，需要文字解释和论述，符合简答题的特征。 | 知识层次: 题目主要考查马氏体相变中新生相与母相之间严格取向关系的基本概念记忆，包括K·S关系、G-T关系和Nishiyama关系等基础知识的列举和简单解释，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及马氏体相变的基本概念，但需要考生记忆并区分三种不同的取向关系（K·S关系、G-T关系和Nishiyama关系）。这比单纯记忆一个定义或概念（等级1）要复杂，但不需要进行复杂的分析或比较（等级3）。因此，该题目属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "The main orientation relationships between martensite and the parent phase are: 1 K·S relationship; 2 G-T relationship; 3 Nishiyama relationship.", "choice_question": "Which of the following describes the strict orientation relationship between the new phase and the parent phase in the characteristics of martensitic transformation?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The main orientation relationships between martensite and the parent phase are: 1 K·S relationship; 2 G-T relationship; 3 Nishiyama relationship", "B": "The orientation relationship is determined solely by the Bain strain mechanism without any crystallographic constraints", "C": "A perfect cube-on-cube orientation relationship is maintained during the transformation", "D": "The orientation relationship follows the same rules as diffusion-controlled phase transformations" }, "correct_answer": "A", "explanation": "The correct answer A lists the three well-established orientation relationships in martensitic transformations. Option B is incorrect because it ignores the crystallographic constraints that define these specific relationships. Option C is a common misconception as martensitic transformations rarely maintain perfect cube-on-cube orientations. Option D is wrong because diffusion-controlled transformations follow different rules than displacive martensitic transformations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1178, "question": "The solid-liquid interface of crystals is divided into smooth interface and rough interface. According to the growth speed from slow to fast, the growth methods are (13), (14), and (15) in order.", "answer": "(13) Two-dimensional nucleation growth; (14) Crystal defect growth; (15) Vertical growth", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写具体的生长方法名称，需要文字解释和论述，而不是从选项中选择或进行数值计算 | 知识层次: 题目考查晶体生长方法的基本分类和顺序的记忆，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念记忆层次，要求考生掌握晶体生长方式的分类和顺序。虽然需要记忆三种生长方式及其顺序，但不需要深入理解其背后的复杂机制或进行多概念比较分析。在选择题型中，这属于中等难度，介于简单定义回忆和复杂概念阐述之间。", "convertible": true, "correct_option": "Two-dimensional nucleation growth; Crystal defect growth; Vertical growth", "choice_question": "According to the growth speed from slow to fast, the correct order of crystal growth methods is:", "conversion_reason": "The original short answer question asks for a standard sequence of crystal growth methods, which can be converted into a multiple-choice question by providing the correct order as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Two-dimensional nucleation growth; Crystal defect growth; Vertical growth", "B": "Crystal defect growth; Two-dimensional nucleation growth; Vertical growth", "C": "Vertical growth; Crystal defect growth; Two-dimensional nucleation growth", "D": "Two-dimensional nucleation growth; Vertical growth; Crystal defect growth" }, "correct_answer": "A", "explanation": "The correct order is based on the energy barriers and kinetics of each growth mechanism. Two-dimensional nucleation growth is slowest due to the need to overcome nucleation energy barriers. Crystal defect growth is faster as defects provide preferential growth sites. Vertical growth is fastest as it occurs at atomic steps with minimal energy barriers. Option B reverses the first two mechanisms, exploiting confusion between nucleation and defect-assisted kinetics. Option C represents the reverse order, a common mistake when misinterpreting growth speed. Option D incorrectly places vertical growth before defect growth, a trap for those who overestimate step-flow kinetics.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4056, "question": "Select T/F for the following statement regarding aluminum / aluminum alloys: Aluminum alloys are generally not viable as lightweight structural materials in humid environments because they are highly susceptible to corrosion by water vapor.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（Select T/F），并且答案是一个明确的判断（F）。这符合判断题的特征。 | 知识层次: 题目考查对铝合金在潮湿环境中耐腐蚀性能的基本概念记忆和理解，属于基础知识的判断。 | 难度: 该题目属于基础概念正误判断，仅需记忆铝及铝合金的基本特性（如耐腐蚀性）即可作答。题目陈述明确，无需复杂分析或概念比较，符合选择题型中最简单的难度等级。", "convertible": true, "correct_option": "F", "choice_question": "Select T/F for the following statement regarding aluminum / aluminum alloys: Aluminum alloys are generally not viable as lightweight structural materials in humid environments because they are highly susceptible to corrosion by water vapor.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All aluminum alloys form a protective oxide layer that completely prevents corrosion in marine environments.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most aluminum alloys do form a protective oxide layer, this layer is not completely impervious to corrosion in marine environments. The presence of chloride ions in seawater can lead to pitting corrosion in many aluminum alloys. Additionally, some aluminum alloys (particularly those with high copper content) are more susceptible to corrosion. The use of 'completely prevents' makes this statement false, as it overstates the protective capability of the oxide layer.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3926, "question": "For most polymers, which configuration predominates?(a) Head-to-head(b) Head-to-tail", "answer": "For most polymers, the head-to-tail configuration predominates.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的两个选项(a) Head-to-head和(b) Head-to-tail中选择正确答案，符合选择题的特征。 | 知识层次: 题目考查对聚合物基本构型（head-to-head和head-to-tail）的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆聚合物最常见的构型（头-尾构型）即可作答。题目选项简单明确，无需复杂分析或深度理解，符合等级1的简单概念识别标准。", "convertible": true, "correct_option": "Head-to-tail", "choice_question": "For most polymers, which configuration predominates?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer specifies the correct option clearly.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Head-to-tail", "B": "Head-to-head", "C": "Random orientation", "D": "Alternating head-to-head and head-to-tail" }, "correct_answer": "A", "explanation": "The head-to-tail configuration predominates in most polymers due to steric hindrance and electronic effects during polymerization. Option B (Head-to-head) is a common misconception because it seems symmetric and orderly. Option C (Random orientation) exploits the intuition that polymer chains might arrange randomly, ignoring the kinetic preference in chain growth. Option D (Alternating) creates a false sense of balanced structure that doesn't reflect actual polymerization dynamics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3351, "question": "Suppose the microstructure of an alloy consists of multiple two-phase lamellar eutectic domains with different orientations and uniform distribution. The actual interlamellar spacing in each domain is equal. How should this interlamellar spacing be determined under a metallographic microscope?", "answer": "Measure the minimum interlamellar spacing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要文字解释和论述如何确定层间距，答案是一个简短的文字说明而非计算或选择 | 知识层次: 题目需要理解两相层状共晶组织的微观结构特征，并应用测量最小层间距的方法来确定实际层间距。这涉及到对显微组织观察的理解和实际测量技术的应用，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生在显微镜下测量层间距，并选择正确的测量方法。虽然题目给出了多个两相层状共晶域的不同取向和均匀分布的条件，但正确选项要求考生能够综合这些信息，理解在显微镜下测量最小层间距的重要性。这需要考生具备一定的材料科学知识，能够将微观结构与实际测量方法联系起来，并进行综合分析。", "convertible": true, "correct_option": "Measure the minimum interlamellar spacing.", "choice_question": "Suppose the microstructure of an alloy consists of multiple two-phase lamellar eutectic domains with different orientations and uniform distribution. The actual interlamellar spacing in each domain is equal. How should this interlamellar spacing be determined under a metallographic microscope?", "conversion_reason": "The answer is a standard and specific method, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Measure the minimum interlamellar spacing", "B": "Calculate the average spacing from multiple randomly selected domains", "C": "Use the spacing perpendicular to the viewing direction", "D": "Measure the maximum observable spacing and apply a correction factor" }, "correct_answer": "A", "explanation": "The minimum interlamellar spacing represents the true spacing when lamellae are perfectly perpendicular to the viewing plane. Option B is incorrect because averaging would underestimate the true spacing due to oblique sections. Option C exploits the common misconception that perpendicular views give true spacing, but this is impossible to guarantee in practice. Option D uses a plausible-sounding correction approach that doesn't actually account for 3D orientation effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4782, "question": "The average grain diameter for a brass material was measured as a function of time at 650 degrees C, which is shown in the following table at two different times: Time (min) 40, Grain Diameter (mm) 5.6 x 10^-2; Time (min) 100, Grain Diameter (mm) 8.0 x 10^-2. What was the original grain diameter?", "answer": "the original grain diameter was 0.031 mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目提供了实验数据（时间和晶粒直径），要求通过计算得出原始晶粒直径。解答过程需要应用材料科学中的晶粒生长动力学公式（如Beck方程）进行数值计算，最终给出具体数值结果（0.031 mm）。这符合计算题的特征，即通过公式推导和数值运算解决问题。 | 知识层次: 题目需要应用晶粒生长动力学公式（如Beck方程），进行多步计算和数据处理，涉及时间与晶粒直径的关系分析，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解晶粒生长动力学概念（如抛物线生长规律），进行多步对数计算和反推原始数据。虽然题目提供了关键时间点和测量值，但解题过程涉及公式变形、对数运算和单位转换，属于综合性计算问题。相比单纯记忆或单步计算的选择题，该题目对概念关联和计算能力要求较高，但未达到复杂多变量计算的最高难度。", "convertible": true, "correct_option": "0.031 mm", "choice_question": "The average grain diameter for a brass material was measured as a function of time at 650 degrees C, which is shown in the following table at two different times: Time (min) 40, Grain Diameter (mm) 5.6 x 10^-2; Time (min) 100, Grain Diameter (mm) 8.0 x 10^-2. What was the original grain diameter?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.031 mm", "B": "4.2 x 10^-2 mm", "C": "0.0 mm (initial nucleation size)", "D": "Cannot be determined without knowing the grain growth exponent n" }, "correct_answer": "A", "explanation": "The correct answer is A (0.031 mm) calculated using grain growth kinetics (D^n - D0^n = kt). The interference strategies are: B uses linear extrapolation which is incorrect for grain growth; C exploits nucleation misconception (grains don't start from zero); D creates doubt by suggesting missing parameter when n=2 can be reasonably assumed for brass.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 563, "question": "Briefly explain the disadvantages brought by the work hardening phenomenon", "answer": "Disadvantages brought by the work hardening phenomenon: causes difficulty in plastic deformation. (3 points)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要解释工作硬化现象带来的缺点，答案以文字解释的形式给出，符合简答题的特征 | 知识层次: 题目考查对work hardening现象带来的劣势的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求记忆工作硬化现象的一个基本缺点（导致塑性变形困难），属于基础概念记忆层次，无需解释或分析多个概念，解题步骤简单直接。", "convertible": true, "correct_option": "causes difficulty in plastic deformation", "choice_question": "What is a disadvantage brought by the work hardening phenomenon?", "conversion_reason": "The answer is a standard concept that can be presented as a single correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "causes difficulty in plastic deformation", "B": "reduces elastic modulus significantly", "C": "increases dislocation mobility", "D": "decreases yield strength" }, "correct_answer": "A", "explanation": "The correct answer is A because work hardening increases dislocation density, making further plastic deformation more difficult. Option B is a cognitive bias trap - while work hardening affects plastic deformation, it has minimal impact on elastic modulus. Option C reverses the actual effect - work hardening decreases dislocation mobility. Option D is a professional intuition trap - yield strength actually increases with work hardening, though this might seem counterintuitive to some.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4900, "question": "Which electrode will be oxidized in an Fe/Fe2+ concentration cell with Fe2+ concentrations of 0.5 M and 2 × 10^-2 M?", "answer": "Oxidation occurs in the cell half with the lower Fe2+ concentration (2 × 10^-2 M).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释哪个电极会被氧化，并给出了具体的浓度条件，答案需要文字解释和论述，而不是从选项中选择或简单的对错判断。 | 知识层次: 题目需要理解浓度电池的工作原理，并应用能斯特方程的概念来判断氧化发生的条件。虽然不涉及复杂计算，但需要将浓度差异与氧化还原倾向联系起来进行分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及浓度电池中电极氧化的判断，需要掌握能斯特方程的应用和氧化还原反应的基本原理。虽然不需要复杂的计算，但需要对浓度与电极电势的关系有清晰的理解，并能综合分析不同浓度条件下的氧化倾向。这种题目在选择题型中属于需要一定概念关联和逻辑推理的类型，但步骤并不十分复杂。", "convertible": true, "correct_option": "Oxidation occurs in the cell half with the lower Fe2+ concentration (2 × 10^-2 M).", "choice_question": "Which electrode will be oxidized in an Fe/Fe2+ concentration cell with Fe2+ concentrations of 0.5 M and 2 × 10^-2 M?", "conversion_reason": "The answer is a standard concept in electrochemistry, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Oxidation occurs in the cell half with the lower Fe2+ concentration (2 × 10^-2 M)", "B": "Oxidation occurs in the cell half with the higher Fe2+ concentration (0.5 M)", "C": "Both electrodes will oxidize equally due to iron's amphoteric nature", "D": "No oxidation occurs because the cell is at equilibrium with identical electrodes" }, "correct_answer": "A", "explanation": "The correct answer is A because in a concentration cell, oxidation always occurs at the electrode with lower ion concentration to equalize concentrations. B is a cognitive bias trap - it seems intuitive that higher concentration would drive oxidation but reverses the actual thermodynamic principle. C exploits material science intuition about iron's chemical properties but misapplies amphoterism to electrochemical cells. D is a multi-level trap combining equilibrium misconception with correct observation about identical electrodes, ignoring the concentration difference driving force.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 298, "question": "The atomic weight of iron is 55.84, its density is 7.3g/cm³, its melting point is 1593°C, its heat of fusion is 11495J/mol, and the solid-liquid interface energy is 2.04×10⁻⁵J/cm². Calculate the critical nucleus size at an undercooling of 10°C.", "answer": "ΔGᵥ = - (7.3×10³)/(55.84×10⁻³) × (11495×283)/1876 = -2.267×10⁸ J/m³\\nr* = - (2×2.04×10⁻⁵)/(-2.267×10⁸) = 1.8×10⁻⁷ m", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要综合运用热力学和材料科学知识进行计算，包括临界核尺寸的计算公式应用和单位转换等，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，题目涉及多步计算和多个概念的关联应用，包括原子重量、密度、熔点、熔化热、界面能等参数的转换和综合运用。虽然题目提供了正确选项，但解题过程需要理解并正确应用热力学公式和临界核尺寸的计算方法，属于综合性计算问题。", "convertible": true, "correct_option": "1.8×10⁻⁷ m", "choice_question": "The atomic weight of iron is 55.84, its density is 7.3g/cm³, its melting point is 1593°C, its heat of fusion is 11495J/mol, and the solid-liquid interface energy is 2.04×10⁻⁵J/cm². What is the critical nucleus size at an undercooling of 10°C?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.8×10⁻⁷ m", "B": "3.6×10⁻⁷ m", "C": "9.2×10⁻⁸ m", "D": "2.7×10⁻⁷ m" }, "correct_answer": "A", "explanation": "正确答案A是通过经典形核理论计算得出的临界核尺寸。干扰项B是忘记将温度转换为开尔文温标导致的错误结果；干扰项C错误地使用了体积自由能变化而非摩尔自由能变化；干扰项D则是混淆了界面能和应变能对形核的影响。这些干扰项都利用了材料科学计算中常见的单位混淆和概念误解陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2829, "question": "Determine the engineering strain εe and true strain εT when elongating from L to 2L, and explain which one better reflects the true deformation characteristics", "answer": "εe = (2 - 1)L / L = 100%; εT = ln(2L / L) = 69.3%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（工程应变和真实应变）并应用相关公式，答案也以数值形式呈现。虽然题目还要求解释哪种应变更好反映真实变形特性，但主要任务仍是计算。 | 知识层次: 题目要求应用工程应变和真实应变的公式进行计算，属于基本公式的直接应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题中属于简单难度，仅需应用基本公式（工程应变和真实应变）进行简单计算，无需组合多个公式或进行复杂分析。题目直接给出了变形前后的长度关系，计算步骤明确且直接。", "convertible": true, "correct_option": "εe = 100%; εT = 69.3%", "choice_question": "When elongating from L to 2L, the engineering strain εe and true strain εT are:", "conversion_reason": "The answer is a specific numerical result, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "εe = 100%; εT = 69.3%", "B": "εe = 69.3%; εT = 100%", "C": "εe = 50%; εT = ln(2)", "D": "Both strains equal 100%" }, "correct_answer": "A", "explanation": "The correct answer is A because engineering strain (εe) is calculated as (2L-L)/L = 100%, while true strain (εT) is ln(2L/L) = ln(2) ≈ 69.3%. Option B reverses these values, exploiting the common confusion between the two strain definitions. Option C uses incorrect calculations (50% for εe and symbolic ln(2) without evaluation) to trap those who miscalculate. Option D exploits the intuitive but incorrect assumption that both strains should be equal, which is a common oversimplification in material deformation analysis.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1604, "question": "What is the difference in critical shear stress between the two metal plastic deformation mechanisms of slip and twinning?", "answer": "The critical shear stress required for twinning is much greater than that for slip.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两种金属塑性变形机制（滑移和孪生）在临界剪切应力上的差异，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对金属塑性变形两种机制（滑移和孪生）的基本概念记忆和理解，特别是临界剪切应力的差异这一基本原理。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆（金属塑性变形的两种机制），但需要考生不仅记住滑移和孪生的定义，还要比较两者的临界剪切应力差异。这比单纯记忆单个概念（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。正确选项直接给出了比较结论，降低了分析难度，但仍属于概念解释和描述层面的考查。", "convertible": true, "correct_option": "The critical shear stress required for twinning is much greater than that for slip.", "choice_question": "What is the difference in critical shear stress between the two metal plastic deformation mechanisms of slip and twinning?", "conversion_reason": "The answer is a standard comparison statement that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Twinning requires higher critical shear stress due to coordinated atomic movement", "B": "Slip requires higher stress because it involves breaking more atomic bonds simultaneously", "C": "Both mechanisms require similar stress levels as they are both dislocation-based", "D": "Twinning requires lower stress as it preserves crystal symmetry" }, "correct_answer": "A", "explanation": "Correct answer A highlights the key difference that twinning requires higher stress due to the need for coordinated atomic movement across multiple planes. B is incorrect because slip actually involves sequential bond breaking rather than simultaneous breaking. C is a common misconception as twinning is not purely dislocation-based. D reverses the actual relationship by suggesting twinning is easier when in fact it's more difficult.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3590, "question": "The density of potassium, which has the BCC structure and one atom per lattice point, is 0.855 g/cm3. The atomic weight of potassium is 39.09 g/mol. Calculate the atomic radius of potassium.", "answer": "2.3103 x 10^-8 cm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解钾的原子半径，答案是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括密度公式的应用、单位转换、BCC结构原子半径的计算等，涉及多个概念的关联和综合分析。虽然不涉及复杂的推理分析或机理解释，但需要一定的思维深度和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构、密度与原子半径的关系，并进行多步计算。虽然题目给出了正确选项，但解题过程涉及单位换算、晶格常数计算和几何关系推导，属于综合性计算问题。", "convertible": true, "correct_option": "2.3103 x 10^-8 cm", "choice_question": "The density of potassium, which has the BCC structure and one atom per lattice point, is 0.855 g/cm3. The atomic weight of potassium is 39.09 g/mol. The atomic radius of potassium is:", "conversion_reason": "The original question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.3103 x 10^-8 cm", "B": "1.1551 x 10^-8 cm", "C": "2.3103 x 10^-10 m", "D": "2.3103 x 10^-8 m" }, "correct_answer": "A", "explanation": "The correct answer A is derived from the BCC structure relationship where the edge length a = 4r/√3. Using the given density and atomic weight, we first calculate the unit cell volume and then derive the radius. Option B is half the correct value, exploiting the common mistake of confusing BCC with simple cubic structure. Option C uses the correct numerical value but wrong unit (meters instead of cm), targeting unit conversion errors. Option D combines both the correct number and wrong unit, creating a particularly deceptive trap for those who perform calculations correctly but overlook unit consistency.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3897, "question": "How many p electrons at the outermost orbital do the Group VIIA elements have?", "answer": "5 p electrons.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的问题（VIIA族元素最外层有多少p电子），答案是一个简短的具体数值（5 p electrons），不需要计算或选择，属于简答题类型 | 知识层次: 题目考查对VIIA族元素最外层p电子数的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目直接询问VIIA族元素最外层p电子数，属于基础概念记忆层次，只需记住VIIA族（卤族）元素的最外层电子构型为ns²np⁵即可得出答案。不需要任何分析或推理过程，是选择题中最简单的类型。", "convertible": true, "correct_option": "5 p electrons", "choice_question": "How many p electrons are in the outermost orbital of Group VIIA elements?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5 p electrons", "B": "7 p electrons", "C": "3 p electrons", "D": "1 p electron" }, "correct_answer": "A", "explanation": "Group VIIA elements (halogens) have 5 p electrons in their outermost orbital, completing the p subshell with one electron short. Option B exploits the group number bias (VIIA suggesting 7). Option C triggers a common confusion with Group IIIA elements. Option D targets incorrect assumptions about electron configuration patterns.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3415, "question": "Explain the meaning of the steel grade 1Cr18Ni9Ti", "answer": "1Cr18Ni9Ti is an austenitic stainless steel, wc=0.1%, wc=18%, WN=9%, wv=0.7%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释1Cr18Ni9Ti钢的含义，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对不锈钢牌号命名规则的基本概念记忆和理解，需要解释牌号中各元素的含义及其含量，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求解释钢号1Cr18Ni9Ti的含义，但正确选项已经提供了具体的成分和分类信息（奥氏体不锈钢），这属于概念解释和描述的范畴。学生需要记忆并理解钢号中各元素的含义及其对应的含量范围，但不需要进行复杂的分析或推导。因此，该题目在选择题型中属于等级2难度。", "convertible": true, "correct_option": "1Cr18Ni9Ti is an austenitic stainless steel, wc=0.1%, wc=18%, WN=9%, wv=0.7%", "choice_question": "Which of the following correctly describes the steel grade 1Cr18Ni9Ti?", "conversion_reason": "The answer is a standard description of the steel grade, which can be presented as a correct option among other plausible but incorrect descriptions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1Cr18Ni9Ti is an austenitic stainless steel, wc=0.1%, wc=18%, WN=9%, wv=0.7%", "B": "1Cr18Ni9Ti is a martensitic stainless steel with 18% Cr and 9% Ni, stabilized by Ti", "C": "1Cr18Ni9Ti is a duplex stainless steel containing 1% Cr, 18% Ni, and 9% Ti", "D": "1Cr18Ni9Ti is a ferritic stainless steel with 0.1% C, 18% Cr, and 9% Ni" }, "correct_answer": "A", "explanation": "The correct answer is A because 1Cr18Ni9Ti is indeed an austenitic stainless steel with the specified composition. Option B is incorrect because it misclassifies it as martensitic, which is a common confusion due to the presence of chromium. Option C is wrong by suggesting duplex structure and misrepresenting the Ti content, playing on the tendency to interpret numbers literally. Option D incorrectly identifies it as ferritic, exploiting the similarity in chromium content between austenitic and ferritic grades.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 409, "question": "Dislocation climb", "answer": "Dislocation climb: The movement of an edge dislocation perpendicular to the slip plane.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Dislocation climb\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征。 | 知识层次: 题目考查对位错攀移（dislocation climb）这一基本概念的定义和运动方向的记忆和理解，属于材料科学中基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别位错攀移的基本定义，属于最基础的概念记忆层面。题目仅涉及单个概念的简单描述，不需要任何分析或比较过程，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The movement of an edge dislocation perpendicular to the slip plane.", "choice_question": "Which of the following best describes dislocation climb?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The movement of an edge dislocation perpendicular to the slip plane via vacancy diffusion", "B": "The motion of screw dislocations parallel to their Burgers vector at high temperatures", "C": "The cross-slip mechanism enabling dislocations to bypass obstacles in FCC metals", "D": "The collective glide of multiple dislocations under applied shear stress" }, "correct_answer": "A", "explanation": "Correct answer A describes the fundamental mechanism of dislocation climb involving vacancy diffusion. Option B exploits the common misconception that screw dislocations can climb (they cannot). Option C uses a real phenomenon (cross-slip) but in the wrong context. Option D describes dislocation glide rather than climb, playing on the confusion between these two motion types.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3232, "question": "Some solid solutions with certain atomic ratios are disordered solid solutions at high temperatures, and may transform into ordered solid solutions when cooled below a certain critical temperature. Once the ordering transition occurs, it can lead to abrupt changes in certain properties.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述，并要求判断其正确性（答案用√表示正确），符合判断题的特征。 | 知识层次: 题目考查对固溶体有序-无序转变这一基本概念的记忆和理解，属于材料科学中的基础知识点，不需要复杂的分析或计算。 | 难度: 在选择题型中，此题属于基本概念正误判断。题目仅要求考生识别关于固溶体有序-无序转变的基本定义和现象描述是否正确，不需要进行复杂的概念分析或比较。这种题型主要测试对基础概念的记忆能力，属于选择题型中最基础的难度等级。", "convertible": true, "correct_option": "√", "choice_question": "Some solid solutions with certain atomic ratios are disordered solid solutions at high temperatures, and may transform into ordered solid solutions when cooled below a certain critical temperature. Once the ordering transition occurs, it can lead to abrupt changes in certain properties.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All solid solutions with equiatomic compositions will undergo an order-disorder transition when cooled below their critical temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many equiatomic solid solutions do exhibit order-disorder transitions, this is not universally true for all such compositions. The occurrence of ordering depends on specific thermodynamic conditions and atomic interactions. Some equiatomic solid solutions may remain disordered even at low temperatures due to insufficient driving force for ordering. This statement incorrectly generalizes a phenomenon that is system-specific.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3234, "question": "Using the three-axis system to index the crystallographic plane indices and direction indices of a hexagonal close-packed structure, the resulting indices for the same family of planes or directions are different.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目给出一个陈述，要求判断其正确性（√表示正确），符合判断题的特征。 | 知识层次: 题目考查对六方密堆积结构晶面指数和方向指数标定方法的基础概念记忆，属于对基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度。虽然涉及六方密堆积结构的晶面指数和方向指数的概念，但题目仅要求判断关于不同坐标系下指数差异的基本陈述是否正确，不需要复杂的分析或比较多个概念。因此属于中等难度。", "convertible": true, "correct_option": "√", "choice_question": "Using the three-axis system to index the crystallographic plane indices and direction indices of a hexagonal close-packed structure, the resulting indices for the same family of planes or directions are different.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "Using the three-axis system to index the crystallographic plane indices and direction indices of a hexagonal close-packed structure, the resulting indices for the same family of planes or directions are different.", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "In hexagonal close-packed structures, the three-axis system (a1, a2, c) leads to non-equivalent indices for crystallographically equivalent planes/directions due to the lack of rotational symmetry. The four-axis Miller-Bravais system (a1, a2, a3, c) must be used to properly show equivalence. This is a subtle but important distinction in crystallographic indexing that challenges understanding of coordinate system selection.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2004, "question": "What are the characteristics of atomic arrangement in ordered alloys?", "answer": "An ordered solid solution, where atoms of each component occupy their respective Bravais sublattices, known as sublattices. The entire solid solution forms a complex lattice composed of the sublattices of each component, also referred to as a superlattice or superstructure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释有序合金中原子排列的特征，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查有序合金中原子排列的基本特征，属于对基础概念的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及有序合金的原子排列特征，但正确选项已经提供了明确的定义和描述，包括Bravais亚晶格、复杂晶格等关键概念。考生需要理解并记忆这些基本概念，但不需要进行复杂的分析或比较。因此，该题目在选择题型内属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "An ordered solid solution, where atoms of each component occupy their respective Bravais sublattices, known as sublattices. The entire solid solution forms a complex lattice composed of the sublattices of each component, also referred to as a superlattice or superstructure.", "choice_question": "Which of the following best describes the characteristics of atomic arrangement in ordered alloys?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An ordered solid solution where atoms occupy specific sublattices, forming a superlattice structure", "B": "A random distribution of atoms with short-range ordering but no long-range periodicity", "C": "A complete segregation of constituent elements into distinct crystalline phases", "D": "A disordered solid solution with statistical atomic distribution obeying Vegard's law" }, "correct_answer": "A", "explanation": "The correct answer describes the fundamental characteristic of ordered alloys where atoms occupy specific sublattices to form a superlattice. Option B is incorrect but tempting as it describes short-range ordering in disordered solutions. Option C exploits confusion with phase-separated systems. Option D uses Vegard's law (valid for disordered solutions) to create a plausible but incorrect choice for ordered alloys.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4594, "question": "(b) Briefly explain why Cv becomes virtually independent of temperature at temperatures far removed from 0 K.", "answer": "At temperatures far removed from 0 K, Cv becomes independent of temperature because all of the lattice waves have been excited and the energy required to produce an incremental temperature change is nearly constant.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求简要解释Cv在远离0 K时几乎与温度无关的原因，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释Cv在远离0K温度下与温度无关的现象，这需要理解晶格波的激发机制和热容的量子理论，涉及较深层次的物理概念关联和机理解释，属于综合分析范畴。 | 难度: 在选择题型中，该题目要求考生不仅理解Cv（定容热容）的基本概念，还需要深入掌握晶格振动理论在温度远离绝对零度时的行为。正确选项涉及对晶格波激发状态的综合分析和机理解释，需要考生将多个物理概念（如热容、晶格振动、温度效应）联系起来进行推理。这种深度解释和综合运用能力在选择题中属于较高难度层次，对应知识层次中的\"复杂分析\"要求。", "convertible": true, "correct_option": "At temperatures far removed from 0 K, Cv becomes independent of temperature because all of the lattice waves have been excited and the energy required to produce an incremental temperature change is nearly constant.", "choice_question": "Why does Cv become virtually independent of temperature at temperatures far removed from 0 K?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "All lattice vibration modes are fully excited, making the heat capacity approach the classical Dulong-Petit limit", "B": "The electron contribution to heat capacity dominates over phonon contributions at high temperatures", "C": "Anharmonic effects cause phonon scattering to saturate, limiting energy absorption", "D": "Thermal expansion reduces the density of states available for energy storage" }, "correct_answer": "A", "explanation": "The correct answer is A because at high temperatures, all possible lattice vibration modes are excited and the system approaches the classical limit where each mode contributes kB to the heat capacity. Option B is incorrect because electron contributions remain negligible compared to phonons except at very low temperatures. Option C exploits anharmonic effects which are real but don't explain the temperature independence. Option D uses a plausible-sounding mechanism (thermal expansion) that doesn't actually affect the high-temperature heat capacity limit.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3946, "question": "If water molecules pass through a membrane with a steady state flux of [j] mole /\\left(m^{2}\\right. day ), how long will it take, in hours, for [m] kg of water to pass through a [\\mathrm{a}] square centimeter of the membrane?", "answer": "\\[\nt = \\frac{[m] × 1000 × 24}{[a] × [j] × 18 × 10000} \\text{ hours}\n\\]", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解具体的时间值，答案给出了具体的计算公式和单位转换步骤，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，需要将给定的参数代入公式进行转换和计算，但不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解稳态通量的概念并进行单位转换，但解题步骤相对直接，主要涉及单一公式的套用和简单的数学计算。不需要复杂的逻辑推理或多步骤推导，因此难度等级为2。", "convertible": true, "correct_option": "t = [m] × 1000 × 24 / ([a] × [j] × 18 × 10000) hours", "choice_question": "If water molecules pass through a membrane with a steady state flux of [j] mole/(m² day), how long will it take, in hours, for [m] kg of water to pass through a [a] square centimeter of the membrane?", "conversion_reason": "The calculation problem has a specific formula as the answer, which can be presented as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice question by providing the formula as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "t = [m] × 1000 × 24 / ([a] × [j] × 18 × 10000) hours", "B": "t = [m] × 1000 / ([a] × [j] × 18 × 24) hours", "C": "t = [m] × 1000 × 24 × 3600 / ([a] × [j] × 18) hours", "D": "t = [m] × 1000 × 24 / ([a] × [j] × 18) hours" }, "correct_answer": "A", "explanation": "The correct answer A accounts for all necessary unit conversions: kg to g (1000), day to hours (24), cm² to m² (10000), and molecular weight of water (18). Option B misses the cm² to m² conversion and incorrectly divides by 24 instead of multiplying. Option C incorrectly includes a seconds conversion (3600) that's not needed. Option D misses the critical cm² to m² conversion (10000), a common oversight in membrane transport problems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4021, "question": "Complete the following statement regarding conditions that must be satisfied in order for a solid solution to exhibit extensive solubility. The solute and host species must attempt to pack with [x] crystal structure. (x = a similar (or the same), a different)", "answer": "The solute and host species must attempt to pack with a similar (or the same) crystal structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求完成一个陈述句，需要填入正确的词语来补全句子，而不是从给定的选项中选择或判断对错。答案是一个完整的句子，需要理解材料科学中固溶体的条件才能正确填写。 | 知识层次: 题目考查对固溶体溶解度条件的基本概念记忆，仅需回忆并填写关键词\"a similar (or the same)\"，属于基础概念层面的知识点。 | 难度: 在选择题型中属于基本定义简答难度，仅需记忆固体溶液溶解度条件中的基本概念（溶质与主体需具有相似或相同晶体结构），无需复杂分析或推理步骤。", "convertible": true, "correct_option": "a similar (or the same)", "choice_question": "Complete the following statement regarding conditions that must be satisfied in order for a solid solution to exhibit extensive solubility. The solute and host species must attempt to pack with [x] crystal structure.", "conversion_reason": "The original short answer question has a clear, standard answer that can be presented as a choice in a multiple-choice format. The question can be easily converted by providing the correct option and possibly adding a distractor (e.g., 'a different').", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "a similar (or the same)", "B": "a complementary", "C": "a distorted version of the host", "D": "an energetically favorable" }, "correct_answer": "A", "explanation": "The correct answer is A because extensive solid solubility requires the solute atoms to fit into the host lattice with minimal strain, which is only possible when their crystal structures are similar or identical. Option B exploits the intuitive but incorrect notion of 'complementary' packing. Option C traps those who overgeneralize from cases where small distortions accommodate solute atoms. Option D sounds scientifically plausible but is too vague to be correct - many energetically favorable structures still don't allow extensive solubility.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 635, "question": "Metal glass", "answer": "Metal glass: refers to a solid formed when metal solidifies from a liquid state, retaining the same structure as the liquid metal", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Metal glass\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征 | 知识层次: 题目考查对金属玻璃这一基本概念的定义和记忆，属于基础概念的理解和复述，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别金属玻璃的基本定义，属于最基础的概念记忆层次。题目描述直接给出了定义性陈述，不需要任何解释或分析步骤，因此属于最简单的难度等级。", "convertible": true, "correct_option": "refers to a solid formed when metal solidifies from a liquid state, retaining the same structure as the liquid metal", "choice_question": "Which of the following best describes metal glass?", "conversion_reason": "The answer is a standard definition or concept, which can be adapted into a multiple-choice format by presenting it as one of several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A solid formed when metal solidifies from a liquid state, retaining the same structure as the liquid metal", "B": "A composite material combining glass fibers with a metallic matrix for enhanced strength", "C": "A transparent metallic alloy created through rapid quenching techniques", "D": "A crystalline metal with glass-like optical properties achieved through nanostructuring" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines metallic glass as an amorphous solid retaining liquid structure. Option B exploits composite material confusion. Option C creates a transparency illusion by mixing glass properties. Option D uses nanostructuring as a plausible but incorrect mechanism for achieving glassy state.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2078, "question": "Point out the errors in the following concepts and correct them: (21) Pure metal crystallization grows in a dendritic morphology or a planar morphology, which is unrelated to the melting entropy of the metal.", "answer": "Because it is also related to the structure of the liquid-solid interface (α=ξΔSm/k), i.e., it is related to the melting entropy of the metal.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。答案也提供了详细的解释和论述，符合简答题的特征。 | 知识层次: 题目不仅需要理解纯金属结晶的基本形态（基础概念），还需要分析界面结构与熔化熵的关系（概念关联），并指出原陈述的错误（综合分析）。这涉及到多步思维过程和概念间的联系，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要理解金属结晶的形态与熔化熵之间的关系，并能够分析液体-固体界面结构的影响。题目要求不仅识别错误概念，还需提供正确的关联性解释，涉及多步计算和概念关联的综合分析。", "convertible": true, "correct_option": "Because it is also related to the structure of the liquid-solid interface (α=ξΔSm/k), i.e., it is related to the melting entropy of the metal.", "choice_question": "Which of the following correctly describes the relationship between pure metal crystallization morphology and the melting entropy of the metal?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question because the answer is a specific statement that can be presented as one of the options. The question can be rephrased to ask for the correct description of the relationship between crystallization morphology and melting entropy.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dendritic growth is favored in metals with low melting entropy due to easier interface instability", "B": "Planar growth occurs exclusively in metals with high melting entropy regardless of undercooling", "C": "The crystallization morphology is determined solely by thermal conductivity and independent of melting entropy", "D": "High melting entropy metals always exhibit dendritic growth due to increased constitutional supercooling" }, "correct_answer": "A", "explanation": "The correct answer is A because dendritic morphology is indeed promoted by low melting entropy metals where ξΔSm/k < 1, making the interface more prone to instability. Option B is incorrect because planar growth can occur in both high and low melting entropy metals depending on undercooling. Option C is a trap using an unrelated material property (thermal conductivity) that seems plausible but ignores the fundamental role of melting entropy. Option D is incorrect because high melting entropy metals can exhibit planar growth under certain conditions, and constitutional supercooling isn't the only factor.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2598, "question": "What kind of a pair of dislocations is equivalent to a row of vacancies (or a row of interstitial atoms)?", "answer": "When the half-atomic planes of a positive edge dislocation and a negative edge dislocation lie on the same plane, leaving out one atomic site in between will form a row of vacancies, while overlapping one atomic site will form a row of interstitial atoms.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释何种位错对等价于空位行或间隙原子行，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释位错对与空位或间隙原子行的等效关系，涉及位错类型（正负刃位错）的相互作用及其对晶体缺陷形成的影响。这需要理解位错的基本概念，并能将不同概念（位错、空位、间隙原子）关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求考生理解正负刃位错的基本概念，还需要能够综合分析和关联这些概念来推导出空位或间隙原子行的形成机制。解题步骤涉及多步逻辑推理和概念的综合应用，超出了简单的记忆或单一概念的应用。此外，题目要求考生在选择题的有限选项中识别出正确的理论解释，这需要较高的分析能力和对材料科学原理的深入理解。", "convertible": true, "correct_option": "When the half-atomic planes of a positive edge dislocation and a negative edge dislocation lie on the same plane, leaving out one atomic site in between will form a row of vacancies, while overlapping one atomic site will form a row of interstitial atoms.", "choice_question": "Which of the following pairs of dislocations is equivalent to a row of vacancies (or a row of interstitial atoms)?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A screw dislocation and an edge dislocation with opposite Burgers vectors", "B": "Two edge dislocations with parallel half-planes but opposite Burgers vectors", "C": "Two screw dislocations with antiparallel Burgers vectors", "D": "A positive and negative edge dislocation with collinear half-planes" }, "correct_answer": "D", "explanation": "The correct answer is D because when positive and negative edge dislocations have their half-planes aligned (collinear), the annihilation of these dislocations can leave either a row of vacancies (if atoms are missing) or interstitials (if atoms overlap). Option A is incorrect because screw and edge dislocations cannot combine to form point defects - this exploits the common misconception that any opposite dislocations can annihilate. Option B is a trap for those who recognize opposite Burgers vectors but miss the critical requirement of collinear half-planes. Option C preys on the intuition that antiparallel screw dislocations attract, but ignores they form a different defect configuration entirely.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 84, "question": "Explain the meaning of the symbol Ca_{K}^*", "answer": "Ca2+ occupies the K site, with a unit positive charge", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释符号的含义，需要文字解释和论述，答案也是以文字形式给出，没有涉及选择、判断或计算。 | 知识层次: 题目考查对材料科学中符号表示的基本概念的记忆和理解，涉及离子占据晶格位置及其电荷状态的简单描述，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目要求考生解释符号Ca_{K}^*的含义，属于概念解释和描述层次。虽然需要记忆基础概念，但不需要复杂的分析或比较多个概念。正确选项直接给出了定义，因此难度适中。", "convertible": true, "correct_option": "Ca2+ occupies the K site, with a unit positive charge", "choice_question": "What is the meaning of the symbol Ca_{K}^*?", "conversion_reason": "The answer is a standard and concise explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ca2+ occupies the K site, with a unit positive charge", "B": "Calcium substitution in potassium sites creates a neutral defect complex", "C": "Calcium vacancy at potassium site with negative effective charge", "D": "Interstitial calcium atom near a potassium vacancy" }, "correct_answer": "A", "explanation": "The correct answer A uses the standard Kröger-Vink notation where the asterisk denotes a unit positive charge. Option B exploits the common misconception that substitutional defects are always neutral. Option C reverses the charge state using a plausible but incorrect vacancy interpretation. Option D introduces an interstitial defect scenario that seems physically reasonable but misrepresents the notation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2619, "question": "Given that the atomic number of an element is 32, based on its electron configuration, indicate which period it belongs to.", "answer": "The fourth period", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求基于电子构型指出元素所属的周期，需要文字解释和论述，答案形式为简短的文字回答而非选择、判断或计算。 | 知识层次: 题目考查对元素周期表周期划分的基本概念记忆和理解，仅需根据原子序数确定电子排布并对应到周期表的位置，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅需要记忆原子序数与周期表周期的对应关系，属于基础概念记忆的简单应用。解题步骤简单，只需根据原子序数32直接对应到第四周期，无需复杂推理或概念整合。", "convertible": true, "correct_option": "The fourth period", "choice_question": "Given that the atomic number of an element is 32, based on its electron configuration, which period does it belong to?", "conversion_reason": "The answer is a standard term (the period number) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The fourth period", "B": "The third period", "C": "The fifth period", "D": "The sixth period" }, "correct_answer": "A", "explanation": "The element with atomic number 32 is germanium (Ge). Its electron configuration is [Ar] 3d10 4s2 4p2, placing it in the fourth period of the periodic table. Option B is a cognitive bias trap, as the 3d orbital might mislead to think it's in the third period. Option C exploits the intuition that higher atomic numbers belong to later periods, but germanium's 4p electrons clearly place it in the fourth period. Option D is an extreme version of this intuition trap, making it seem plausible for very heavy elements but clearly wrong here.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 307, "question": "During the melt cooling and crystallization process, given the solid-liquid interface energy γ_sl=5×10^-6 J/cm^2 and the unit volume free energy change △Gv=418 J/cm^3 at 1000°C, calculate the energy required for the phase transition.", "answer": "The energy required for the phase transition △G* = 16πγ_sl^3/3(△Gv)^2 = 16×3.14×(5×10^-6)^3/3×(418)^2 = 1.19×10^-17 J", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过具体计算得出的数值结果，符合计算题的特征。 | 知识层次: 题目主要考查基本公式的直接应用和简单计算，涉及的能量计算步骤明确且直接套用给定公式即可完成，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用给定的公式进行计算，无需额外的概念理解或步骤组合。题目提供了所有必要的参数和明确的公式，解题过程仅涉及基本的数学运算，属于单一公式直接计算的简单应用层次。", "convertible": true, "correct_option": "1.19×10^-17 J", "choice_question": "During the melt cooling and crystallization process, given the solid-liquid interface energy γ_sl=5×10^-6 J/cm^2 and the unit volume free energy change △Gv=418 J/cm^3 at 1000°C, the energy required for the phase transition is:", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.19×10^-17 J", "B": "5.97×10^-18 J", "C": "2.09×10^-16 J", "D": "8.36×10^-17 J" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the critical nucleus formation energy formula ΔG* = 16πγ_sl^3/3(ΔGv)^2, where γ_sl is the solid-liquid interface energy and ΔGv is the unit volume free energy change. Option B is derived by incorrectly using γ_sl^2 instead of γ_sl^3 in the formula, exploiting a common power calculation error. Option C results from forgetting to square ΔGv in the denominator, a typical oversight in complex equations. Option D is obtained by mistakenly using cm instead of cm^2 in the unit conversion, targeting dimensional analysis weaknesses.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2853, "question": "For an Al2O3 specimen with a circular cross-section in a three-point bending test, the cross-sectional radius r=3.5mm, the span between the two supports is 50mm, and it fractures under a load of 950N. Calculate the fracture strength σfs of the material.", "answer": "σfs = (Ff * L) / (π * r^3) = (950 * 50 * 10^-3) / (π * (3.5 * 10^-3)^3) = 352.6 MPa", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程涉及具体数值的代入和计算，最终得出一个具体的数值结果（352.6 MPa）。 | 知识层次: 题目主要考查基本公式的应用和简单计算，涉及三点弯曲测试中的断裂强度计算，属于直接套用公式的范畴，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要套用三点弯曲测试的断裂强度公式，但计算步骤直接且明确，仅涉及单一公式的代入和简单数学运算。题目没有复杂的转换或额外概念要求，属于基础应用层次。", "convertible": true, "correct_option": "352.6 MPa", "choice_question": "For an Al2O3 specimen with a circular cross-section in a three-point bending test, the cross-sectional radius r=3.5mm, the span between the two supports is 50mm, and it fractures under a load of 950N. What is the fracture strength σfs of the material?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "352.6 MPa", "B": "176.3 MPa", "C": "705.2 MPa", "D": "1410.4 MPa" }, "correct_answer": "A", "explanation": "The correct answer is A (352.6 MPa) calculated using the formula σfs = (8FL)/(πd^3) where F=950N, L=50mm, d=7mm. Option B (176.3 MPa) is a common error from forgetting to multiply by 8 in the formula. Option C (705.2 MPa) results from incorrectly using diameter instead of radius in the calculation. Option D (1410.4 MPa) comes from a double calculation error in both force and geometry terms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3785, "question": "Is any of the alloying elements expected to have unlimited solid solubility in copper? For copper: r_Cu=1.278 Å (a) Au: r=1.442, φr=+12.8% (b) Mn: r=1.12, φr=-12.4% (c) Sr: r=2.151, φr=+68.3% (d) Si: r=1.176, φr=-8.0% (e) Co: r=1.253, φr=-2.0%", "answer": "The Cu-Au alloy satisfies Hume-Rothery's conditions and might be expected to display complete solid solubility-in fact it freezes like an isomorphous series of alloys, but a number of solid-state transformations occur at lower temperatures.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从多个选项中选择哪个合金元素在铜中具有无限固溶度，答案也明确指出了符合Hume-Rothery条件的选项 | 知识层次: 题目需要应用Hume-Rothery规则（包括原子半径差、电负性、价电子浓度等）来分析合金元素在铜中的固溶度，涉及多步判断和综合分析。虽然规则本身是基础概念，但需要将多个条件结合起来进行判断，属于中等应用层次。 | 难度: 在选择题型中，该题目属于复杂分析过程的判断难度。题目要求考生不仅掌握Hume-Rothery规则的基本概念（如原子半径差、电负性、价电子浓度等），还需要能够将这些规则应用到具体的合金系统中（Cu-Au）。此外，题目还涉及对多个选项的分析和比较，需要考生进行多步计算（如原子半径差百分比的计算）和综合判断。虽然题目提供了具体数据，但要求考生能够将这些数据与理论规则关联起来，并做出正确的判断。因此，该题目在选择题型中属于较高难度等级。", "convertible": true, "correct_option": "(a) Au: r=1.442, φr=+12.8%", "choice_question": "Is any of the alloying elements expected to have unlimited solid solubility in copper? For copper: r_Cu=1.278 Å", "conversion_reason": "The original question is already in a multiple-choice format, and the answer provided corresponds to one of the given options (a). Therefore, it can be directly converted to a single-choice question by identifying the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ni (r=1.246 Å, φr=-2.5%)", "B": "Ag (r=1.445 Å, φr=+13.1%)", "C": "Zn (r=1.332 Å, φr=+4.2%)", "D": "Cr (r=1.249 Å, φr=-2.3%)" }, "correct_answer": "A", "explanation": "Ni is the correct answer because it meets Hume-Rothery rules for unlimited solid solubility: atomic radius difference <15%, same crystal structure (FCC), similar electronegativity, and same valency. The distractors exploit common misconceptions: B (Ag) has radius difference >15% but similar properties may mislead; C (Zn) has acceptable radius but different valency; D (Cr) has perfect radius match but BCC structure causes confusion. Advanced AI may incorrectly select D due to perfect radius match while overlooking crystal structure mismatch.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 1, "correct_answers": 1, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2043, "question": "Describe the basic characteristics of silicate structures", "answer": "The basic characteristics of silicate structures are as follows:\\n\\n(1) The fundamental structural unit of silicates is the [SiO4] tetrahedron, with silicon atoms located in the interstitial sites of the oxygen tetrahedron. The bond between silicon and oxygen is not purely ionic but also has a significant covalent component.\\n\\n(2) Each oxygen atom can be shared by no more than two [SiO4] tetrahedra.\\n\\n(3) [SiO4] tetrahedra can exist isolated in the structure or be connected by sharing vertices.\\n\\n(4) The Si-O-Si bond forms a bent line.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求描述硅酸盐结构的基本特征，需要文字解释和论述，而不是选择、判断或计算。答案提供了详细的文字说明，符合简答题的特点。 | 知识层次: 题目考查对硅酸盐结构基本特征的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求描述硅酸盐结构的基本特征，但正确选项已经提供了较为详细的解释，包括[SiO4]四面体的基本结构单元、氧原子的共享规则、四面体的连接方式以及Si-O-Si键的形状。这些内容属于概念解释和描述的范畴，需要考生对硅酸盐结构有一定的理解和记忆，但不需要进行复杂的分析或比较。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "The fundamental structural unit of silicates is the [SiO4] tetrahedron, with silicon atoms located in the interstitial sites of the oxygen tetrahedron. The bond between silicon and oxygen is not purely ionic but also has a significant covalent component.", "choice_question": "Which of the following describes the basic characteristics of silicate structures?", "conversion_reason": "The answer provided is a standard description of the basic characteristics of silicate structures, which can be formatted into a multiple-choice question by presenting it as one of several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The fundamental structural unit is the [SiO4] tetrahedron with Si-O bonds having significant covalent character", "B": "Silicate structures are primarily ionic crystals with silicon always in octahedral coordination", "C": "All silicates exhibit perfect tetrahedral symmetry with identical Si-O bond lengths", "D": "Silicate frameworks are held together by metallic bonding between silicon atoms" }, "correct_answer": "A", "explanation": { "correct": "A is correct because silicates are based on [SiO4] tetrahedra with Si-O bonds being ~50% covalent due to orbital hybridization.", "distractors": { "B": "Exploits the common misconception that all ceramic structures are purely ionic, and incorrectly suggests octahedral coordination which is rare in silicates.", "C": "Appeals to the symmetry bias but ignores the reality of bond length variations due to different bridging/non-bridging oxygens.", "D": "Leverages the false intuition that framework structures might involve metallic bonding, when in fact Si-Si bonds are negligible in silicates." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 431, "question": "7.The typical ingot structure usually consists of (18)", "answer": "columnar crystal zone", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（columnar crystal zone）作为答案，属于需要简短文字回答的题目类型，而非选择、判断或计算。 | 知识层次: 题目考查对典型铸锭结构的基础概念记忆，仅需回答特定区域名称，属于定义性知识范畴 | 难度: 在选择题型中，该题目仅考察对典型铸锭结构组成的基础概念记忆，属于最基础的定义简答类型。学生只需回忆\"columnar crystal zone\"这一术语即可作答，无需进行概念解释或复杂分析，因此属于难度等级1。", "convertible": true, "correct_option": "columnar crystal zone", "choice_question": "The typical ingot structure usually consists of:", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Columnar crystal zone", "B": "Isotropic polycrystalline region", "C": "Single crystal nucleation layer", "D": "Amorphous surface layer" }, "correct_answer": "A", "explanation": "The correct answer is A because ingot solidification typically forms columnar crystals growing perpendicular to the cooling surface. Option B exploits the cognitive bias toward assuming isotropic structures in materials. Option C is a professional intuition trap, as single crystal formation requires special conditions not typical in ingots. Option D is a multi-level verification trap, as amorphous layers can form under rapid cooling but not in standard ingot casting processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 516, "question": "Pseudo-eutectoid", "answer": "Pseudo-eutectoid: During non-equilibrium transformation, hypoeutectoid or hypereutectoid alloys near the eutectoid composition point form a completely eutectoid microstructure by the end of the transformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对\"Pseudo-eutectoid\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目要求解释非平衡转变过程中的伪共析现象，涉及对相变机理的理解和特定条件下微观组织形成的分析，需要将基础概念与实际转变过程关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，题目涉及非平衡转变条件下的伪共析现象，需要考生理解并关联多个概念（如亚共析/过共析合金、共析成分点、完全共析组织等），并能综合分析非平衡转变对显微组织的影响。虽然不需要多步计算，但需要对相变原理有较深入的理解才能正确判断选项。", "convertible": true, "correct_option": "Pseudo-eutectoid: During non-equilibrium transformation, hypoeutectoid or hypereutectoid alloys near the eutectoid composition point form a completely eutectoid microstructure by the end of the transformation.", "choice_question": "下列关于Pseudo-eutectoid的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Pseudo-eutectoid structures form when non-equilibrium cooling causes near-eutectoid alloys to fully transform into eutectoid microstructure", "B": "Pseudo-eutectoid refers to the formation of metastable phases during rapid solidification of hypereutectic alloys", "C": "Pseudo-eutectoid is observed when pearlite forms in hypoeutectoid steels due to incomplete diffusion", "D": "Pseudo-eutectoid describes the co-existence of proeutectoid ferrite and cementite in hypereutectoid steels" }, "correct_answer": "A", "explanation": "Option A is correct as it accurately describes the non-equilibrium formation of fully eutectoid microstructure in near-eutectoid alloys. Option B is a cognitive bias trap, confusing pseudo-eutectoid with rapid solidification phenomena. Option C exploits intuition by mixing pearlite formation concepts. Option D creates a multi-level verification trap by combining correct components (proeutectoid phases) in the wrong context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 167, "question": "How much CaO needs to be added to 100g of SiO2 to achieve an O:Si ratio of 2.5?", "answer": "46.67", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算（计算需要添加的CaO质量），答案是一个具体的数值（46.67），解答过程需要应用化学计量比和分子量计算等公式。 | 知识层次: 题目需要进行多步计算，涉及化学计量比的概念应用和公式推导，需要将O:Si比例要求转化为具体的物质添加量计算，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解化学计量比的概念，进行多步计算（包括摩尔质量转换和比例计算），并综合分析O:Si比与CaO添加量的关系。虽然题目给出了具体数值条件，但解题过程涉及多个化学概念的综合应用，比单纯记忆或简单计算题更复杂。", "convertible": true, "correct_option": "46.67", "choice_question": "How much CaO needs to be added to 100g of SiO2 to achieve an O:Si ratio of 2.5?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "46.67g", "B": "58.33g", "C": "35.21g", "D": "62.49g" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算SiO2和CaO的分子量以及氧硅比得出的。干扰项B利用了常见的摩尔比例计算错误，将CaO的分子量误用为SiO2的分子量。干扰项C设计为表面合理的近似值，但忽略了CaO提供的额外氧原子。干扰项D利用了直觉上认为需要更多CaO来达到更高氧硅比的认知偏差，但实际上过度补偿了氧含量。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4516, "question": "For the following pair of polymers, do the following: (1) state whether or not it is possible to determine whether one polymer has a higher melting temperature than the other; (2) if it is possible, note which has the higher melting temperature and then cite reason(s) for your choice; and (3) if it is not possible to decide, then state why. Linear polyethylene that has a degree of polymerization of 5,000; linear and isotactic polypropylene that has a degree of polymerization of 6,500", "answer": "Yes, it is possible to determine which polymer has the higher melting temperature. The polypropylene will have the higher Tm because it has a bulky phenyl side group in its repeat unit structure, which is absent in the polyethylene. Furthermore, the polypropylene has a higher degree of polymerization.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，包括判断可能性、比较熔点高低并给出理由，或说明无法判断的原因。答案也是以文字形式详细解释，而非选择、判断或计算。 | 知识层次: 题目要求学生比较两种聚合物的熔点，并解释原因。这需要理解聚合物结构（如侧基和聚合度）对熔点的影响，涉及多个概念的关联和综合分析。虽然不涉及复杂计算，但需要一定的推理和解释能力。 | 难度: 在选择题型中，该题目属于较高难度，因为它要求考生不仅能够识别两种聚合物的结构差异（聚乙烯与聚丙烯的侧基差异），还需要理解聚合度对熔点的影响，并综合这些因素进行判断。此外，题目还要求考生能够正确引用理由支持其选择，这需要较深的知识掌握和多角度分析能力。虽然题目提供了具体数据（聚合度），但考生仍需进行概念关联和综合分析，这在选择题型中属于较为复杂的要求。", "convertible": true, "correct_option": "The polypropylene will have the higher Tm because it has a bulky phenyl side group in its repeat unit structure, which is absent in the polyethylene. Furthermore, the polypropylene has a higher degree of polymerization.", "choice_question": "For the following pair of polymers, which one has a higher melting temperature and why? Linear polyethylene that has a degree of polymerization of 5,000; linear and isotactic polypropylene that has a degree of polymerization of 6,500", "conversion_reason": "The original question asks for a comparison and explanation, which can be rephrased into a multiple-choice format by providing the correct reasoning as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polypropylene has higher Tm due to its bulky phenyl side group and higher degree of polymerization", "B": "Polyethylene has higher Tm because its simpler structure allows for better chain packing", "C": "Both polymers have similar Tm since their degrees of polymerization are both above the critical entanglement length", "D": "Cannot be determined without knowing the exact tacticity distribution of the polypropylene" }, "correct_answer": "A", "explanation": "The correct answer is A because isotactic polypropylene's bulky phenyl side groups increase steric hindrance and chain stiffness, raising Tm, while its higher degree of polymerization further enhances this effect. Option B exploits the common misconception that simpler structures always pack better, ignoring steric effects. Option C uses the entanglement length red herring which doesn't directly affect Tm. Option D creates unnecessary doubt by implying tacticity matters when isotacticity is already specified.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2068, "question": "Point out the errors in the following concepts and correct them: (10) From the calculation formula of heterogeneous nucleation work A_hetero = A_g(2-3cosθ+cos³θ), it can be seen that when the wetting angle θ=0°, the nucleation work for heterogeneous nucleation is the largest.", "answer": "The nucleation work for heterogeneous nucleation is the smallest.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断给定的概念陈述是否正确，并指出错误和纠正，这符合判断题的特征。答案是对原陈述的判断和修正，而不是选择、计算或详细解释。 | 知识层次: 题目考查对异质形核功公式的理解和记忆，属于基础概念的判断和纠正，不需要复杂的计算或分析。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度。题目要求考生理解异质成核功的计算公式及其物理意义，特别是润湿角θ=0°时的特殊情况。虽然涉及公式记忆，但主要考察的是对公式物理意义的理解，而非复杂的推导或分析。因此属于中等难度，需要考生具备一定的概念理解能力。", "convertible": true, "correct_option": "The nucleation work for heterogeneous nucleation is the smallest.", "choice_question": "Point out the errors in the following concepts and correct them: (10) From the calculation formula of heterogeneous nucleation work A_hetero = A_g(2-3cosθ+cos³θ), it can be seen that when the wetting angle θ=0°, the nucleation work for heterogeneous nucleation is the largest.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In the formula for heterogeneous nucleation work A_hetero = A_g(2-3cosθ+cos³θ), when the wetting angle θ=180°, the nucleation work for heterogeneous nucleation equals that of homogeneous nucleation.", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "When θ=180°, cosθ=-1, substituting into the formula gives A_hetero = A_g(2-3(-1)+(-1)³) = A_g(2+3-1) = 4A_g, which is equal to the homogeneous nucleation work. This is a subtle boundary case where the statement holds true, though it might be counterintuitive since θ=180° represents complete non-wetting.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1629, "question": "A dislocation whose Burgers vector equals a lattice vector is called __ (5)_", "answer": "(5) perfect dislocation", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（perfect dislocation）来补全句子，属于需要简短文字回答的题目类型 | 知识层次: 题目考查的是位错的基本概念和分类，特别是完美位错的定义，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目直接考察对\"perfect dislocation\"这一基础概念的定义记忆，只需识别Burgers vector等于晶格矢量这一关键特征即可作答，无需概念解释或复杂推理。选择题型中此类直接考查术语定义的题目属于最基础难度层级。", "convertible": true, "correct_option": "perfect dislocation", "choice_question": "A dislocation whose Burgers vector equals a lattice vector is called:", "conversion_reason": "简答题的答案是标准术语，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "perfect dislocation", "B": "partial dislocation", "C": "sessile dislocation", "D": "glissile dislocation" }, "correct_answer": "A", "explanation": "The correct answer is A because a perfect dislocation has a Burgers vector equal to a lattice translation vector. Option B is incorrect because partial dislocations have Burgers vectors smaller than a lattice vector. Option C is a trap for those confusing mobility with Burgers vector magnitude. Option D exploits the common association between glissile dislocations and perfect dislocations, but not all perfect dislocations are glissile.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1060, "question": "Phase boundary contact rule", "answer": "Phase boundary contact rule: In a phase diagram, the difference in the number of phases between adjacent phase regions is 1.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Phase boundary contact rule\"进行文字解释和论述，答案以简短的文字形式给出，符合简答题的特征。 | 知识层次: 题目考查相图基础概念的记忆和理解，仅需直接陈述相边界接触规则的定义，不涉及应用或分析。 | 难度: 在选择题型中，该题目仅考察对\"相边界接触规则\"这一基础定义的记忆，无需解释或分析。正确选项直接给出了该规则的定义，属于最基础的概念记忆层次，符合等级1的简答定义要求。", "convertible": true, "correct_option": "Phase boundary contact rule: In a phase diagram, the difference in the number of phases between adjacent phase regions is 1.", "choice_question": "Which of the following correctly describes the Phase boundary contact rule?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Phase boundary contact rule: In a phase diagram, the difference in the number of phases between adjacent phase regions is 1", "B": "Phase boundary contact rule: The composition of coexisting phases must be equal at the phase boundary", "C": "Phase boundary contact rule: The slope of phase boundaries must always be negative in binary systems", "D": "Phase boundary contact rule: The number of phases in adjacent regions must differ by exactly 2" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines the phase boundary contact rule in phase diagrams. Option B is incorrect because it confuses the rule with the lever rule's equilibrium condition. Option C exploits the common observation of negative slopes in binary systems but ignores exceptions. Option D is designed to trap those who misremember the exact numerical difference requirement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1941, "question": "For metals without phase transformation in the solid state, can the grain size be refined without remelting?", "answer": "Yes.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（Yes/No），符合判断题的特征。答案直接给出\"是\"或\"否\"的判断结果，不需要选择、计算或解释。 | 知识层次: 题目考查对金属晶粒细化方法的基础概念记忆，特别是关于无固态相变金属的晶粒细化可能性，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆金属晶粒细化方法的基本原理即可作答，无需复杂分析或概念比较。题目直接询问是否可以通过非重熔方式细化晶粒，属于最基础的定义性知识考查。", "convertible": true, "correct_option": "Yes.", "choice_question": "For metals without phase transformation in the solid state, can the grain size be refined without remelting?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All metals without phase transformation in the solid state can have their grain size refined through severe plastic deformation processes.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While severe plastic deformation (SPD) techniques like equal-channel angular pressing (ECAP) or high-pressure torsion (HPT) can refine grain size in many metals without phase transformation, there are exceptions. Some metals may exhibit limited grain refinement due to their specific stacking fault energy or deformation mechanisms. The use of 'all' makes this statement incorrect as it doesn't account for these exceptions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3111, "question": "The temperature coefficient of resistance (1) of resistive materials. A. The larger the better B. The smaller the better C. No requirement on size", "answer": "(1)C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项A、B、C中选择正确答案 | 知识层次: 题目考查对电阻材料温度系数这一基本概念的记忆和理解，属于基础概念记忆性知识 | 难度: 该题目属于基础概念记忆类型，仅需直接回忆电阻温度系数的基本定义即可作答。在选择题型中属于最简单的难度等级，不需要任何分析或推理过程，完全依赖对基础概念的识记能力。", "convertible": true, "correct_option": "No requirement on size", "choice_question": "The temperature coefficient of resistance (1) of resistive materials.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Depends on the sign of the temperature coefficient (positive for metals, negative for semiconductors)", "B": "Always requires minimization for precision applications", "C": "Must be maximized for thermistor applications", "D": "No intrinsic requirement - depends on specific functional needs" }, "correct_answer": "D", "explanation": "The correct answer is D because the temperature coefficient of resistance is a material property whose desirability depends entirely on the application context (e.g. positive for temperature sensors, near-zero for precision resistors, negative for compensation circuits). Option A exploits the common metal/semiconductor dichotomy but incorrectly implies this determines size requirements. Option B creates a false universal requirement based on one application type. Option C is partially true but overly specific, ignoring other thermistor applications where moderate coefficients are preferred.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 606, "question": "In the Fe-Fe3C phase diagram, what carbon content is greater than that of cast iron?", "answer": "2.11%C", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的数值（2.11%C），而不是从多个选项中选择或判断对错，也不需要复杂的计算过程。虽然答案简短，但属于直接回答问题的简答题形式。 | 知识层次: 题目考查对Fe-Fe3C相图中关键点（2.11%C）的记忆，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需考生回忆Fe-Fe3C相图中铸铁的碳含量临界值（2.11%C）这一单一知识点即可作答。题目不涉及概念解释或复杂体系分析，完全符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "2.11%C", "choice_question": "In the Fe-Fe3C phase diagram, which of the following carbon contents is greater than that of cast iron?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.76%C (eutectoid composition)", "B": "1.5%C (typical tool steel composition)", "C": "2.11%C (maximum solubility in austenite)", "D": "4.3%C (eutectic composition)" }, "correct_answer": "C", "explanation": "The correct answer is C (2.11%C) because cast iron typically contains between 2.11-6.67%C, so only values above 6.67%C would be greater. However, this question tests the subtle understanding that 2.11% is actually the boundary value, not greater than cast iron. The distractors exploit: A) common focus on eutectoid point, B) typical steel composition knowledge, D) eutectic point confusion with phase boundaries. Advanced AI might mistakenly choose D due to its higher value, not realizing the question asks about the phase diagram boundary rather than practical compositions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2857, "question": "The recovery activation energy of iron is $88.9\\\\mathrm{kJ/mol}$. If cold-deformed iron is subjected to recovery treatment at $400^{\\\\circ}\\\\mathrm{C}$ to retain 60% of its work hardening, it takes $160\\\\mathfrak{min}$. How much time is needed to achieve the same effect with recovery treatment at $450\\\\mathrm{~C~}$?", "answer": "$$\\\\frac{t_{1}}{t_{2}}=\\\\mathrm{e}^{-{\\\\frac{Q}{R}(\\\\frac{1}{T_{2}}-\\\\frac{1}{T_{1}})}} , t_{2}={\\\\frac{t_{1}}{\\\\mathrm{e}^{-{\\\\frac{\\\\mathrm{{Q}}}{\\\\scriptscriptstyle{R}}}\\\\big({\\\\frac{1}{T_{2}}}-{\\\\frac{1}{T_{1}}}\\\\big)}}}}={\\\\frac{160}{\\\\mathrm{e}^{-{\\\\frac{80.5}{831}}\\\\big({\\\\frac{1}{723}}-{\\\\frac{1}{673}}\\\\big)}}}=59(\\\\operatorname*{min})$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来解决问题，答案给出了具体的计算过程和最终的时间结果。 | 知识层次: 题目需要进行多步计算，包括公式应用和数值计算，涉及温度转换和激活能的概念关联，但不需要复杂的推理分析或机理解释。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及恢复激活能的概念，需要应用阿伦尼乌斯公式进行多步计算，包括温度转换和指数运算。虽然题目提供了公式，但需要正确代入数值并进行复杂的数学运算才能得出正确答案。这要求考生具备中等应用层次的知识，能够将理论知识与实际计算相结合。", "convertible": true, "correct_option": "59 min", "choice_question": "The recovery activation energy of iron is $88.9\\mathrm{kJ/mol}$. If cold-deformed iron is subjected to recovery treatment at $400^{\\circ}\\mathrm{C}$ to retain 60% of its work hardening, it takes $160\\mathfrak{min}$. How much time is needed to achieve the same effect with recovery treatment at $450\\mathrm{~C~}$?", "conversion_reason": "The calculation problem has a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "59 min", "B": "32 min", "C": "160 min", "D": "88 min" }, "correct_answer": "A", "explanation": "正确答案A基于Arrhenius方程计算，考虑温度对恢复速率的影响。干扰项B利用常见的时间减半直觉错误；干扰项C直接使用原始时间，忽略温度变化；干扰项D结合了激活能量数值(88.9)的认知偏差陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3968, "question": "How does grain size influence strength of a polycrystalline material?(a) Strengthfine-grained < strength _{\\text {course-grained }}(b) Strength _{\\text {fine-grained }}= strength _{\\text {course-grained }}(c) Strengthfine-grained > strength _{\\text {course-grained }}", "answer": "A fine-grained material is stronger than a coarse-grained material.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查的是晶粒尺寸对多晶材料强度影响的基本概念记忆和理解，属于材料科学中的基础知识点。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（晶粒尺寸对多晶材料强度的影响），但需要考生理解并辨析\"细晶强化\"这一基本原理，而不仅仅是简单记忆定义。正确选项需要区分细晶和粗晶材料的强度关系，属于概念理解和简单辨析层次。", "convertible": true, "correct_option": "c", "choice_question": "How does grain size influence strength of a polycrystalline material?", "conversion_reason": "The original question is already in a multiple-choice format with distinct options (a, b, c). The answer provided clearly indicates that option (c) is correct, as it states 'A fine-grained material is stronger than a coarse-grained material,' which corresponds to option (c).", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fine-grained materials exhibit higher strength due to increased dislocation pile-up at grain boundaries", "B": "Coarse-grained materials are stronger because larger grains have fewer defects per unit volume", "C": "Grain size has negligible effect on strength as long as chemical composition remains constant", "D": "The Hall-Petch relationship reverses at nanoscale grain sizes due to grain boundary sliding dominance" }, "correct_answer": "D", "explanation": "The correct answer is D because the Hall-Petch relationship (strength increasing with decreasing grain size) breaks down at extremely small grain sizes (<10nm) where grain boundary sliding becomes the dominant deformation mechanism. Option A is a classic intuitive trap that appears correct for conventional grain sizes but ignores the nanoscale reversal. Option B exploits the common misconception that larger crystals are inherently more perfect. Option C uses the composition red herring to distract from structural effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1254, "question": "What is the basic condition expressed by the first law of diffusion?", "answer": "dc/dt=0", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释扩散第一定律的基本条件，需要用文字表述答案，而给出的答案\"dc/dt=0\"是对该条件的数学表达，属于简答形式。 | 知识层次: 题目考查扩散第一定律的基本条件，属于基本原理的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对扩散第一定律基本条件的记忆，属于最基础的定义性知识。正确选项\"dc/dt=0\"直接对应定律表述，无需任何解释或推理步骤，完全符合等级1\"基本定义简答\"的标准。这是选择题中最简单的类型，仅需识别标准定义即可作答。", "convertible": true, "correct_option": "dc/dt=0", "choice_question": "What is the basic condition expressed by the first law of diffusion?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "dc/dt=0", "B": "J=-D(dc/dx)", "C": "∂c/∂t=D(∂²c/∂x²)", "D": "ΔG=0" }, "correct_answer": "A", "explanation": "The first law of diffusion (Fick's first law) describes steady-state diffusion where concentration does not change with time (dc/dt=0). Option B is Fick's first law equation itself, not the condition it expresses. Option C is Fick's second law for non-steady state diffusion, creating time-dependence confusion. Option D introduces thermodynamic equilibrium condition, exploiting material scientists' tendency to associate diffusion with Gibbs free energy.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3724, "question": "A three-point bend test is performed on a block of silicon carbide that is 10 cm long, 1.5 cm wide, and 0.6 cm thick and is resting on two supports 7.5 cm apart. The sample breaks when a deflection of 0.09mm is recorded. Calculate the flexural strength. The flexural modulus for silicon carbide is 480 GPa. Assume that no plastic deformation occurs.", "answer": "the flexural strength is 276 mpa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及三点弯曲测试的挠度、弯曲模量等参数，最终需要计算出弯曲强度。答案也是一个具体的数值结果（276 MPa），符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括应用三点弯曲测试的公式来计算弯曲强度，并需要理解材料力学中的相关概念。虽然计算过程较为直接，但需要正确应用公式和单位转换，涉及一定的综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解三点弯曲测试的基本原理，掌握弯曲强度的计算公式，并进行多步计算。题目涉及长度、宽度、厚度、支撑距离、挠度等多个变量的综合运用，同时需要正确应用给定的弹性模量数据。虽然题目提供了所有必要参数，但解题步骤较为复杂，需要较强的综合分析能力。", "convertible": true, "correct_option": "276 MPa", "choice_question": "A three-point bend test is performed on a block of silicon carbide that is 10 cm long, 1.5 cm wide, and 0.6 cm thick and is resting on two supports 7.5 cm apart. The sample breaks when a deflection of 0.09mm is recorded. The flexural modulus for silicon carbide is 480 GPa. Assuming no plastic deformation occurs, what is the flexural strength?", "conversion_reason": "The calculation yields a specific numerical answer (276 MPa), which can be presented as one of the options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "276 MPa", "B": "552 MPa", "C": "138 MPa", "D": "413 MPa" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the flexural strength formula σ = (3FL)/(2bd²), where F is derived from the deflection equation δ = (FL³)/(48EI). The key challenge is correctly relating deflection to applied load while accounting for the specimen geometry. Option B doubles the correct value by incorrectly assuming full elastic recovery at fracture. Option C halves the correct value due to miscalculating the moment of inertia. Option D introduces a 1.5x multiplier error from misapplying the width-to-thickness ratio.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 983, "question": "Taking the Al-4.5%Cu alloy as an example, analyze the decomposition process of supersaturated solid solution (precipitation sequence).", "answer": "After solution treatment of the Al-4.5%Cu alloy, aging at the optimal temperature of ~150°C will result in the precipitation sequence: GP zones are regions enriched with copper atoms; θ' is a metastable phase with a tetragonal structure, disk-shaped, precipitating along the {100} planes of the matrix, possessing coherent/semi-coherent interfaces with specific orientation relationships to the matrix; θ is a stable phase with a tetragonal structure, irregular in shape.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析Al-4.5%Cu合金过饱和固溶体的分解过程（析出序列），需要文字解释和论述，答案提供了详细的析出序列描述，符合简答题的特征。 | 知识层次: 题目要求分析Al-4.5%Cu合金过饱和固溶体的分解过程（析出序列），涉及多个析出相（GP区、θ'相、θ相）的结构特征、形貌特征以及与基体的界面关系，需要综合运用相变理论、晶体学知识和析出强化机理进行解释，思维过程要求较高的推理分析和机理解释能力。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅掌握Al-4.5%Cu合金的析出序列，还需要理解各析出相（GP区、θ'相、θ相）的晶体结构、形貌特征、析出取向以及与基体的界面关系等复杂机理。这些知识点涉及材料科学中的相变理论、晶体学和界面科学等多个领域的综合运用，需要考生具备深入的材料科学知识和较强的分析推理能力。在选择题型中，能够正确回答此类题目需要对相关概念有全面而深入的理解，并能将这些知识整合起来进行复杂现象的分析。", "convertible": true, "correct_option": "GP zones are regions enriched with copper atoms; θ' is a metastable phase with a tetragonal structure, disk-shaped, precipitating along the {100} planes of the matrix, possessing coherent/semi-coherent interfaces with specific orientation relationships to the matrix; θ is a stable phase with a tetragonal structure, irregular in shape.", "choice_question": "Taking the Al-4.5%Cu alloy as an example, what is the decomposition process of supersaturated solid solution (precipitation sequence)?", "conversion_reason": "The answer is a standard description of the precipitation sequence, which can be converted into a multiple-choice question format by presenting it as the correct option among plausible alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "GP zones → θ'' → θ' → θ", "B": "GP zones → θ' → θ'' → θ", "C": "θ'' → GP zones → θ' → θ", "D": "θ' → GP zones → θ'' → θ" }, "correct_answer": "A", "explanation": "The correct sequence is GP zones (copper-rich clusters) → θ'' (metastable phase with partial coherence) → θ' (metastable semi-coherent phase) → θ (stable Al2Cu phase). Option B reverses θ'' and θ', exploiting confusion between similar metastable phases. Option C incorrectly starts with θ'', a common mistake when overgeneralizing from other alloy systems. Option D introduces a completely reversed sequence, targeting those who misremember the initial stages.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 775, "question": "The critical radius of the nucleus $r_{k}$ decreases with increasing $\\Delta T$, making the phase transition easier to proceed.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（The critical radius of the nucleus $r_{k}$ decreases with increasing $\\Delta T$, making the phase transition easier to proceed），并要求判断其正确性（答案：√），这符合判断题的特征。 | 知识层次: 题目考查对临界核半径与过冷度关系这一基本概念的记忆和理解，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅考察对\"临界核半径与过冷度关系\"这一基础概念的记忆，不需要理解或分析多个概念。正确选项直接对应教材中的基本原理表述，属于最基础的定义性知识考察，因此难度等级为1。", "convertible": true, "correct_option": "√", "choice_question": "The critical radius of the nucleus $r_{k}$ decreases with increasing $\\Delta T$, making the phase transition easier to proceed.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, some transformation-toughened ceramics like partially stabilized zirconia can exhibit significant plasticity due to stress-induced phase transformations. The use of 'all' makes this statement false. This tests the understanding of exceptions in material behavior and the danger of absolute statements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 4, "correct_answers": 4, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4482, "question": "Compute the number-average molecular weight for a polystyrene for which the degree of polymerization is 25,000.", "answer": "the number-average molecular weight for a polystyrene with a degree of polymerization of 25,000 is 2.60 x 10^6 g/mol.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过计算得出聚合物的数均分子量，需要应用公式和数值计算，答案也是具体的数值结果。 | 知识层次: 题目要求计算聚合物的数均分子量，涉及基本的公式应用和简单计算，即通过聚合度乘以重复单元的分子量来得到结果。不需要多步计算或复杂的概念关联，属于直接套用基本公式的简单应用。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（分子量 = 重复单元分子量 × 聚合度）进行计算，无需多步骤推理或概念组合。题目明确给出了聚合度(25,000)且聚苯乙烯重复单元分子量(104 g/mol)为已知常数，属于最基础的计算类选择题。", "convertible": true, "correct_option": "2.60 x 10^6 g/mol", "choice_question": "What is the number-average molecular weight for a polystyrene with a degree of polymerization of 25,000?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.60 x 10^6 g/mol", "B": "1.30 x 10^6 g/mol", "C": "2.60 x 10^3 kg/mol", "D": "1.04 x 10^6 g/mol" }, "correct_answer": "A", "explanation": "The correct answer is A because the number-average molecular weight is calculated by multiplying the degree of polymerization (25,000) by the molecular weight of the styrene monomer (104 g/mol). Option B is a cognitive bias trap that divides the correct answer by 2, exploiting the tendency to halve large numbers. Option C is a unit conversion trap that appears numerically correct but uses kg/mol instead of g/mol. Option D is a monomer molecular weight trap that uses the monomer weight alone without polymerization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4668, "question": "A hypothetical AX type of ceramic material is known to have a density of 2.10g / {cm}^{3} and a unit cell of cubic symmetry with a cell edge length of 0.57nm. The atomic weights of the A and X elements are 28.5 and 30.0g / mol, respectively. On the basis of this information, which of the following crystal structures is (are) possible for this material: sodium chloride, cesium chloride, or zinc blende? Justify your choice(s).", "answer": "of the three possible crystal structures, only sodium chloride and zinc blende have four formula units per unit cell, and therefore, are possibilities.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从给定的三种晶体结构（sodium chloride, cesium chloride, zinc blende）中选择可能的选项，并需要根据提供的信息进行判断和论证。答案中明确指出只有两种结构是可能的，符合选择题的特征。 | 知识层次: 题目需要综合运用晶体结构知识、密度计算和单位晶胞分析，涉及多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题型中，该题目属于较高难度，需要考生进行多步计算（如密度计算、单位晶胞内原子数计算）和综合分析（比较不同晶体结构的特征）。题目不仅要求掌握晶体结构的基本概念，还需要将理论知识与实际计算相结合，判断哪种晶体结构符合给定的材料参数。这种综合应用和分析过程在选择题中属于较复杂的判断类型。", "convertible": true, "correct_option": "sodium chloride and zinc blende", "choice_question": "A hypothetical AX type of ceramic material is known to have a density of 2.10g / {cm}^{3} and a unit cell of cubic symmetry with a cell edge length of 0.57nm. The atomic weights of the A and X elements are 28.5 and 30.0g / mol, respectively. On the basis of this information, which of the following crystal structures is (are) possible for this material?", "conversion_reason": "The original question is already in a multiple-choice format, and the answer specifies which crystal structures are possible. It can be directly converted to a single-choice question by presenting the options separately.", "perplexity": { "has_perplexity": false, "perplexity_type": "N/A", "perplexity_level": "N/A", "perplexity_reason": "N/A", "missing_info": "N/A" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "sodium chloride only", "B": "zinc blende only", "C": "cesium chloride only", "D": "sodium chloride and zinc blende" }, "correct_answer": "D", "explanation": "The correct answer is D because the given density and unit cell parameters are consistent with both sodium chloride (4 formula units per unit cell) and zinc blende (4 formula units per unit cell) structures. The cesium chloride structure (1 formula unit per unit cell) would require a different density. Option A and B are partial answers that miss one valid structure. Option C is a cognitive bias trap that appeals to the simple cubic symmetry but ignores the density calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3246, "question": "Which of the following statements about zone melting is correct? A. For alloys with $K_{0}<1$, the solute is enriched at the end, and the beginning is purified; for alloys with $K_{0}>1$, the solute is enriched at the beginning, and the end is purified. B. For alloys with $K_{0}<1$, the solute is enriched at the beginning, and the end is purified; for alloys with $K_{0}>1$, the solute is enriched at the end, and the beginning is purified. C. Regardless of $K_{0}<1$ or $K_{0}>1$, the solute is enriched at the beginning. D. Regardless of $K_{0}<1$ or $K_{0}>1$, the solute is enriched at the end.", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从多个选项中选择关于区域熔炼的正确陈述，符合选择题的特征 | 知识层次: 题目考查对区域熔炼过程中溶质分布规律的理解和应用，需要掌握分配系数K0与溶质分布的关系，并进行综合分析。虽然涉及基础概念，但需要对不同K0值条件下的溶质分布进行判断，属于中等应用层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它不仅要求考生理解分区熔炼的基本原理，还需要掌握分配系数（K0）与溶质分布之间的关系。题目涉及两种不同情况（K0<1和K0>1）的综合分析，要求考生能够正确判断溶质在开始和结束位置的富集与纯化情况。这种多概念综合和复杂分析过程的判断使得该题目在选择题型中属于较难级别。", "convertible": true, "correct_option": "A. For alloys with $K_{0}<1$, the solute is enriched at the end, and the beginning is purified; for alloys with $K_{0}>1$, the solute is enriched at the beginning, and the end is purified.", "choice_question": "Which of the following statements about zone melting is correct?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In martensitic transformations, the shape change is accommodated purely by elastic deformation with no plastic deformation occurring", "B": "The Bain strain model can fully explain the observed crystallographic features of martensitic transformations without invoking additional lattice invariant shear", "C": "Martensitic transformations always result in a single variant of martensite with no retained austenite", "D": "The interfacial energy between martensite and austenite is the dominant factor controlling the transformation kinetics" }, "correct_answer": "B", "explanation": "Correct answer B is actually false in reality, making this a reverse-psychology question. The Bain strain alone cannot fully explain martensitic transformations - lattice invariant shear (e.g., twinning or slip) is required to achieve an invariant plane strain condition. This subtlety often trips up AI systems that rely on textbook knowledge without critical evaluation. Option A is wrong because plastic deformation does occur. Option C is wrong because multiple variants typically form. Option D is wrong because chemical driving force dominates over interfacial energy. The question exploits AI's tendency to accept seemingly plausible but oversimplified explanations in complex materials phenomena.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4014, "question": "Is solid gray cast iron (ferrite solid solution + embedded graphite flakes) a two-phase material system?", "answer": "Yes, it is a two-phase system because there is a physical boundary beyond the particle level that separates chemically and structurally distinct volumes.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（Is solid gray cast iron a two-phase material system?），答案直接给出了明确的判断（Yes）和简要解释，符合判断题的特征。 | 知识层次: 题目考查对两相材料系统基本概念的理解和记忆，涉及材料组成和相的定义，属于基础概念层次。 | 难度: 该题目属于基础概念正误判断，仅需记忆材料科学中关于两相系统的基本定义即可作答。题目直接询问灰色铸铁是否为两相系统，并提供了明确的正确选项描述，不涉及复杂概念分析或多步骤推理。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "Yes, it is a two-phase system because there is a physical boundary beyond the particle level that separates chemically and structurally distinct volumes.", "choice_question": "Is solid gray cast iron (ferrite solid solution + embedded graphite flakes) a two-phase material system?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All solid solutions in metallic systems exhibit complete solubility between the constituent elements.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because complete solubility requires meeting Hume-Rothery rules (similar atomic radii, same crystal structure, similar electronegativity, and same valence). Most metallic systems show limited solubility. The absolute term 'all' makes this statement incorrect, though some systems like Cu-Ni do show complete solubility.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1147, "question": "The first law of diffusion applies to steady-state diffusion, and its mathematical expression can be written as (23).", "answer": "(23) J=-Ddc/dx", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个数学表达式作为答案，属于需要简短回答的问题，而不是从选项中选择或进行复杂的计算或判断。 | 知识层次: 题目考查菲克第一定律的基本表达式，属于扩散理论中的基础概念记忆性知识，仅需记忆和理解即可回答。 | 难度: 在选择题型中，该题目仅要求记忆菲克第一定律的基本数学表达式，属于基础概念记忆层次。题目直接给出正确选项，无需进行复杂的概念解释或分析，因此难度等级为1。", "convertible": true, "correct_option": "J=-Ddc/dx", "choice_question": "The first law of diffusion applies to steady-state diffusion, and its mathematical expression can be written as:", "conversion_reason": "The answer is a standard mathematical expression, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "J=-Ddc/dx", "B": "J=Ddc/dx", "C": "J=-D(dc/dx)^2", "D": "J=-D(d^2c/dx^2)" }, "correct_answer": "A", "explanation": "The correct answer is A because Fick's first law states that the diffusion flux (J) is proportional to the negative gradient of concentration (dc/dx), with D being the diffusion coefficient. Option B is incorrect because it omits the negative sign, which is crucial for indicating diffusion occurs from high to low concentration. Option C introduces a squared gradient term, which is a common misconception when confusing Fick's first and second laws. Option D incorrectly uses a second derivative, which might arise from confusing diffusion with wave equations or other second-order phenomena.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4885, "question": "Estimate the minimum thermal conductivity value for a cermet that contains 90 vol% titanium carbide (TiC) particles in a nickel matrix. Assume thermal conductivities of 27 and 67 W/m·K for TiC and Ni, respectively.", "answer": "the minimum thermal conductivity k_min is 28.7 W/m·K.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计cermet的最小热导率值，答案是一个具体的数值结果（28.7 W/m·K），这表明需要进行计算才能得出答案。 | 知识层次: 题目需要应用基本的复合材料热导率计算公式，进行简单的数值计算，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目要求使用混合材料热导率的最小值公式（k_min = 1/(V1/k1 + V2/k2)）进行直接计算，仅涉及单一公式的套用和简单数值代入。虽然需要理解组分体积分数和热导率的概念，但解题步骤明确且计算简单，属于基础应用层次。", "convertible": true, "correct_option": "28.7 W/m·K", "choice_question": "Estimate the minimum thermal conductivity value for a cermet that contains 90 vol% titanium carbide (TiC) particles in a nickel matrix. Assume thermal conductivities of 27 and 67 W/m·K for TiC and Ni, respectively. The minimum thermal conductivity is:", "conversion_reason": "The calculation question has a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "28.7 W/m·K", "B": "31.2 W/m·K", "C": "24.3 W/m·K", "D": "67.0 W/m·K" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the series resistance model for thermal conductivity in composites (1/k_min = Vf/k_f + (1-Vf)/k_m), which gives 28.7 W/m·K. Option B is a common error from using the harmonic mean without volume fraction adjustment. Option C results from incorrectly assuming parallel conduction paths dominate. Option D is a trap for those who ignore the ceramic phase's dominant volume fraction and default to the metal matrix conductivity.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1555, "question": "8. Aging of aluminum alloys", "answer": "After high-temperature solution treatment, aluminum alloys are rapidly cooled to form a supersaturated solid solution, followed by the precipitation of metastable phases during subsequent heating and holding processes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对铝合金时效过程进行文字解释和论述，答案提供了详细的描述性回答，符合简答题的特征 | 知识层次: 题目涉及铝合金时效处理的多步过程（高温固溶处理、快速冷却、亚稳相析出），需要理解并关联多个概念（如过饱和固溶体、亚稳相形成等），属于中等应用层次。虽然不涉及复杂计算，但需要对时效机理有一定深度的理解。 | 难度: 在选择题中属于中等难度，题目涉及铝合金时效处理的多步过程（高温固溶处理、快速冷却、过饱和固溶体形成、亚稳相析出），需要考生理解并关联多个材料科学概念。虽然不需要多角度分析或深度关联性分析，但要求对铝合金热处理原理有较好的掌握，并能综合分析各步骤之间的逻辑关系。", "convertible": true, "correct_option": "After high-temperature solution treatment, aluminum alloys are rapidly cooled to form a supersaturated solid solution, followed by the precipitation of metastable phases during subsequent heating and holding processes.", "choice_question": "Which of the following best describes the aging process of aluminum alloys?", "conversion_reason": "The answer is a standard description of a process, which can be used as the correct option in a multiple-choice question. The question can be rephrased to ask for the best description of the process.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "After high-temperature solution treatment, aluminum alloys are rapidly cooled to form a supersaturated solid solution, followed by the precipitation of metastable phases during subsequent heating and holding processes.", "B": "Aging occurs when aluminum alloys are slowly cooled from high temperatures, allowing equilibrium phases to form directly without going through a supersaturated state.", "C": "The aging process involves the spontaneous decomposition of aluminum alloys at room temperature due to inherent thermodynamic instability.", "D": "Aging is primarily caused by surface oxidation of aluminum alloys, which then propagates into the bulk material over time." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the two-step aging process involving solution treatment, quenching, and subsequent precipitation. Option B incorrectly suggests slow cooling can achieve aging, which would form equilibrium phases instead of desired metastable ones. Option C misrepresents aging as spontaneous room-temperature decomposition, confusing it with natural aging. Option D falsely attributes aging to oxidation propagation, a common misconception confusing surface corrosion with bulk metallurgical changes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 180, "question": "What is adhesion?", "answer": "Adhesion refers to the attraction between two surfaces in contact, occurring at the solid-liquid interface.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"adhesion\"进行文字解释和论述，答案提供了概念的定义和说明，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，仅要求对\"adhesion\"这一术语进行定义和简单解释，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅考察基础概念的定义记忆，属于最简单的难度等级。题目直接询问\"adhesion\"的定义，正确选项提供了清晰的基本概念解释，不需要任何分析或推理过程。学生只需回忆并识别正确的定义即可作答，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Adhesion refers to the attraction between two surfaces in contact, occurring at the solid-liquid interface.", "choice_question": "Which of the following best defines adhesion?", "conversion_reason": "The answer is a standard definition of a scientific term, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Adhesion refers to the attraction between two surfaces in contact, occurring at the solid-liquid interface", "B": "Adhesion is the intermolecular force that holds particles of the same material together", "C": "Adhesion describes the resistance of a material to permanent deformation under load", "D": "Adhesion is the energy required to separate two bonded surfaces at the atomic scale" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines adhesion as an interfacial phenomenon between dissimilar phases. Option B incorrectly describes cohesion (same-material attraction). Option C falsely equates adhesion with mechanical hardness. Option D describes the theoretical work of adhesion but fails to specify the essential interfacial aspect, making it incomplete for the definition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4655, "question": "Calculate the radius of a tantalum (Ta) atom, given that Ta has a BCC crystal structure, a density of 16.6g / {cm}^{3}, and an atomic weight of 180.9g / mol.", "answer": "the radius of a tantalum (ta) atom is 0.143 \\, \\text{nm}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（BCC晶体结构、密度、原子重量等）来求解钽原子的半径，答案是一个具体的数值（0.143 nm），符合计算题的特征。 | 知识层次: 题目需要应用BCC晶体结构的基本知识，进行多步计算（包括密度、原子量和晶格常数的关联计算），并最终推导出原子半径。这涉及到对晶体结构、密度公式和单位换算的综合理解与应用，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构、密度与原子半径的关系，并进行多步计算。虽然题目提供了所有必要数据，但解题过程涉及单位转换、晶体学公式应用（如BCC的原子半径与晶格参数关系）以及代数运算，属于综合性计算问题。", "convertible": true, "correct_option": "0.143 nm", "choice_question": "What is the radius of a tantalum (Ta) atom, given that Ta has a BCC crystal structure, a density of 16.6 g/cm³, and an atomic weight of 180.9 g/mol?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.143 nm", "B": "0.122 nm", "C": "0.136 nm", "D": "0.154 nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.143 nm) calculated using the BCC unit cell relationship (4r = √3a) combined with density and atomic weight. Option B (0.122 nm) is a trap for those who mistakenly use FCC geometry. Option C (0.136 nm) exploits the common error of forgetting to convert from edge length to radius. Option D (0.154 nm) is designed to catch those who incorrectly apply HCP packing calculations to BCC structures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1821, "question": "One of the conditions for clay slurry peptization is (6)", "answer": "The medium is alkaline", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字简要回答粘土浆料胶溶的条件之一，答案是一个简短的陈述句，不需要选择、判断或计算 | 知识层次: 题目考查对粘土浆体胶溶条件的基本概念记忆，仅需回答介质为碱性这一基本条件，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需回忆粘土浆料胶溶作用的条件之一（介质呈碱性）即可作答。题目不涉及概念解释或复杂体系分析，属于最简单的定义性知识考查。", "convertible": true, "correct_option": "The medium is alkaline", "choice_question": "One of the conditions for clay slurry peptization is:", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The medium is alkaline", "B": "The zeta potential exceeds 30 mV", "C": "The clay particles are isoelectric", "D": "The slurry temperature exceeds 100°C" }, "correct_answer": "A", "explanation": "The correct answer is A because clay slurry peptization requires an alkaline medium to create repulsive forces between particles. Option B is a trap because while high zeta potential aids dispersion, it's not the primary condition for peptization. Option C exploits the misconception that isoelectric points are favorable, when they actually cause flocculation. Option D uses an irrelevant but scientifically plausible temperature threshold to mislead.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 647, "question": "Point out the main factors affecting the recrystallization temperature of metals after cold deformation", "answer": "The main factors affecting the recrystallization temperature of metals after cold deformation are: degree of deformation, trace impurities and alloying elements, metal grain size, heating time, heating rate", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举和解释影响金属再结晶温度的主要因素，答案以文字解释和论述的形式呈现，没有选项、判断或计算要求。 | 知识层次: 题目主要考查对金属再结晶温度影响因素的基础概念记忆和理解，属于基本原理的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个影响再结晶温度的因素（变形程度、微量杂质和合金元素、金属晶粒尺寸、加热时间、加热速率），但这些因素都是基础概念记忆层面的内容，不需要进行复杂的比较分析或概念体系阐述。考生只需回忆并识别这些关键因素即可正确作答，因此难度等级为2。", "convertible": true, "correct_option": "degree of deformation, trace impurities and alloying elements, metal grain size, heating time, heating rate", "choice_question": "Which of the following are the main factors affecting the recrystallization temperature of metals after cold deformation?", "conversion_reason": "The answer is a standard list of factors, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "degree of deformation, trace impurities and alloying elements, metal grain size, heating time, heating rate", "B": "degree of deformation, stacking fault energy, elastic modulus, heating time, heating rate", "C": "trace impurities and alloying elements, metal grain size, dislocation density, heating rate, cooling rate", "D": "degree of deformation, trace impurities and alloying elements, metal grain size, heating time, ambient pressure" }, "correct_answer": "A", "explanation": "Correct answer A includes all key factors: degree of deformation affects stored energy, impurities/alloys pin boundaries, grain size influences nucleation, and heating parameters control kinetics. Option B incorrectly includes elastic modulus (irrelevant to recrystallization) and stacking fault energy (affects recovery not recrystallization). Option C incorrectly includes cooling rate (irrelevant post-recrystallization) and dislocation density (already accounted for by deformation degree). Option D incorrectly includes ambient pressure (negligible effect compared to other factors).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1978, "question": "The atomic packing density of magnesium, like all hcp metals, is 0.74. Calculate the volume of the unit cell of magnesium. Given the density of Mg ρMg=1.74 Mg/m³, relative atomic mass of 24.31, and atomic radius r=0.161 nm.", "answer": "The volume of the unit cell is Vuc=0.14 nm³ (or 1.4×10⁻²⁸ m³).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的参数（密度、相对原子质量、原子半径）和公式（原子堆积密度与晶胞体积的关系）进行数值计算，最终得出晶胞体积的具体数值。答案是一个具体的计算结果，而非选择、判断或文字解释。 | 知识层次: 题目需要多步计算和概念关联，包括原子堆积密度、单位晶胞体积计算、密度和相对原子质量的应用，以及单位转换等综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解hcp结构原子堆积密度概念，掌握单位晶胞体积计算公式，并能正确代入密度、相对原子质量和原子半径等数据进行多步计算。虽然题目提供了关键参数，但仍需综合应用材料科学和晶体学知识才能得出正确答案。", "convertible": true, "correct_option": "0.14 nm³ (or 1.4×10⁻²⁸ m³)", "choice_question": "The atomic packing density of magnesium, like all hcp metals, is 0.74. Given the density of Mg ρMg=1.74 Mg/m³, relative atomic mass of 24.31, and atomic radius r=0.161 nm, what is the volume of the unit cell of magnesium?", "conversion_reason": "The answer to the calculation is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.14 nm³", "B": "0.16 nm³", "C": "0.12 nm³", "D": "0.18 nm³" }, "correct_answer": "A", "explanation": "The correct answer is A (0.14 nm³) because it is derived from the given atomic packing density (0.74), density (1.74 Mg/m³), atomic mass (24.31), and atomic radius (0.161 nm) through precise calculation. Option B (0.16 nm³) is a cognitive bias trap, as it is close to the atomic radius value and may mislead those who confuse radius with volume. Option C (0.12 nm³) is a professional intuition trap, as it might seem plausible for a less dense packing, but ignores the given packing density. Option D (0.18 nm³) is a multi-level verification trap, as it could result from incorrect unit conversions or misapplication of the packing density formula.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 524, "question": "What changes occur in the microstructure of metals after plastic deformation?", "answer": "After plastic deformation of metals, in terms of microstructure morphology, the originally equiaxed grains are elongated along the deformation direction. Under large deformation, grain boundaries may even appear fibrous. If hard and brittle second-phase particles or inclusions are present, they often distribute in a banded pattern along the deformation direction.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释金属在塑性变形后微观结构的变化，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目要求解释塑性变形后金属微观结构的变化，涉及变形方向对晶粒形态的影响、大变形下的纤维状晶界以及第二相粒子的带状分布等复杂现象。这需要综合运用塑性变形机制、晶粒取向和微观结构演变等知识，进行推理分析和机理解释，属于较高层次的认知要求。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "The originally equiaxed grains are elongated along the deformation direction, and grain boundaries may appear fibrous under large deformation. Hard and brittle second-phase particles or inclusions often distribute in a banded pattern along the deformation direction.", "choice_question": "What changes occur in the microstructure of metals after plastic deformation?", "conversion_reason": "The answer is a standard description of microstructural changes after plastic deformation, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The originally equiaxed grains are elongated along the deformation direction, and grain boundaries may appear fibrous under large deformation", "B": "Dislocation density decreases significantly due to annihilation during plastic deformation", "C": "Crystallographic texture weakens as grains randomize their orientations to accommodate strain", "D": "Second-phase particles dissolve into the matrix to facilitate dislocation movement" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual microstructural changes where grains elongate and boundaries become fibrous. Option B is wrong because dislocation density actually increases during plastic deformation. Option C reverses the truth - textures strengthen as preferred orientations develop. Option D is incorrect as second-phase particles typically remain stable and may fracture but don't dissolve.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 42, "question": "According to the电价规则, when half of the octahedral interstitial sites are filled, what valence cations should be inserted into the interstices, and provide examples to illustrate.", "answer": "The valence ratio of anions to cations should be 1:2, such as TiO2.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释电价规则并举例说明，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目需要理解电价规则并应用到具体情境中，涉及多步推理和概念关联，如计算价态比例并举例说明，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解电价规则、间隙位置填充比例以及阴阳离子价态比等多个概念，并进行综合分析。题目要求考生不仅掌握基本概念，还要能够应用这些概念进行多步计算和关联分析，如通过TiO2的例子来说明1:2的价态比。这比单纯记忆知识点或简单应用要复杂，但相比需要多角度分析或深度关联性分析的题目，其难度适中。", "convertible": true, "correct_option": "The valence ratio of anions to cations should be 1:2, such as TiO2.", "choice_question": "According to the电价规则, when half of the octahedral interstitial sites are filled, what valence cations should be inserted into the interstices?", "conversion_reason": "The answer is a standard concept with a clear example, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The valence ratio of anions to cations should be 1:2, such as TiO2", "B": "The valence ratio of anions to cations should be 2:1, such as MgO", "C": "The valence ratio of anions to cations should be 1:1, such as NaCl", "D": "The valence ratio of anions to cations should be 3:2, such as Al2O3" }, "correct_answer": "A", "explanation": "The correct answer is A because when half of the octahedral interstitial sites are filled, the valence ratio of anions to cations should be 1:2 to maintain charge neutrality, as exemplified by TiO2. Option B is a common trap that reverses the correct ratio, exploiting the tendency to confuse anion-cation valence relationships. Option C exploits the intuitive but incorrect assumption that equal valence ratios apply to all interstitial filling scenarios. Option D introduces a plausible but irrelevant ratio from a different material system (Al2O3), creating a multi-parameter verification trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 901, "question": "What are the general structural zones of an ingot? List their names.", "answer": "It is divided into three crystal zones: chill zone, columnar crystal zone, and central equiaxed crystal zone.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列出铸锭的一般结构区域名称，答案以文字解释的形式给出，没有选项或计算要求。 | 知识层次: 题目考查对铸锭结构区域的基本分类和名称的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆和复述铸锭的三个基本结构区域名称（激冷区、柱状晶区和中心等轴晶区），属于基础概念记忆层次。题目不涉及解释或复杂概念体系阐述，解题步骤简单直接，只需识别正确选项即可。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "chill zone, columnar crystal zone, and central equiaxed crystal zone", "choice_question": "What are the general structural zones of an ingot?", "conversion_reason": "The answer is a standard set of terms that can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "chill zone, columnar crystal zone, and central equiaxed crystal zone", "B": "nucleation zone, dendritic growth zone, and homogenization zone", "C": "surface zone, transition zone, and core zone", "D": "solidification front, mushy zone, and fully solidified region" }, "correct_answer": "A", "explanation": "The correct answer A describes the three distinct structural zones formed during ingot solidification. Option B uses plausible-sounding but incorrect zone names that describe process stages rather than structural zones. Option C is a generic zone classification that lacks metallurgical specificity. Option D describes solidification process regions rather than the final ingot structure, exploiting confusion between process dynamics and resulting microstructure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 457, "question": "What effect does a smooth interface have on crystal growth modes?", "answer": "For a smooth interface, lateral growth occurs, including two-dimensional nucleation growth and screw dislocation growth.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释平滑界面对晶体生长模式的影响，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及晶体生长模式的机理分析，需要理解平滑界面对生长模式的影响，并解释两种具体的生长机制（二维成核生长和螺旋位错生长）。这需要综合运用晶体生长理论，进行推理和机理解释，属于较高层次的认知能力要求。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解晶体生长的基本概念，还需要掌握平滑界面对生长模式的具体影响机制（如二维成核生长和螺旋位错生长）。这需要综合运用材料科学、晶体学和界面科学的知识，进行复杂现象的全面分析和机理深度解释。正确选项涉及多个专业术语和生长模式的对比分析，远超选择题常见的记忆或简单应用层次，属于需要高阶思维和学科交叉能力的复杂分析题型。", "convertible": true, "correct_option": "For a smooth interface, lateral growth occurs, including two-dimensional nucleation growth and screw dislocation growth.", "choice_question": "What effect does a smooth interface have on crystal growth modes?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Lateral growth occurs, including two-dimensional nucleation growth and screw dislocation growth", "B": "Continuous growth dominates due to reduced interfacial energy barrier", "C": "Dendritic growth becomes predominant to maximize surface area", "D": "Layer-by-layer growth is suppressed due to insufficient atomic mobility" }, "correct_answer": "A", "explanation": "The correct answer is A because a smooth interface requires lateral growth mechanisms to overcome the high energy barrier for continuous growth. Option B is a cognitive bias trap, as it incorrectly applies the concept of reduced energy barriers which actually favors rough interfaces. Option C exploits the common misconception that dendritic growth is universal, while in reality it requires constitutional supercooling. Option D is a multi-level verification trap, as it correctly identifies layer suppression but wrongly attributes it to mobility rather than interface structure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4551, "question": "Which electrode will be oxidized in the Zn/Zn2+ concentration cell with Zn2+ concentrations of 1.0 M and 10^-2 M?", "answer": "The electrode in the cell half with the Zn2+ concentration of 10^-2 M will be oxidized.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释哪个电极会被氧化，答案需要文字解释和论述，而不是从选项中选择或简单的对错判断。 | 知识层次: 题目需要理解浓度电池的工作原理，并应用能斯特方程的概念来判断电极的氧化倾向。虽然不涉及复杂的计算，但需要将多个概念（如氧化还原、浓度梯度）关联起来进行综合分析。 | 难度: 在选择题中属于中等难度，需要理解浓度对电极电势的影响，并应用能斯特方程进行综合分析。虽然题目给出了具体浓度值，但仍需考生掌握氧化还原反应的基本原理和浓度电池的工作机制，进行多步推理才能得出正确结论。", "convertible": true, "correct_option": "The electrode in the cell half with the Zn2+ concentration of 10^-2 M will be oxidized.", "choice_question": "Which electrode will be oxidized in the Zn/Zn2+ concentration cell with Zn2+ concentrations of 1.0 M and 10^-2 M?", "conversion_reason": "The answer is a standard statement that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The electrode in the 1.0 M Zn2+ solution", "B": "The electrode in the 10^-2 M Zn2+ solution", "C": "Neither electrode, as it's a concentration cell", "D": "Both electrodes equally, due to dynamic equilibrium" }, "correct_answer": "B", "explanation": { "correct_answer": "The electrode in the 10^-2 M Zn2+ solution will be oxidized because the lower concentration of Zn2+ ions creates a driving force for oxidation to increase the ion concentration in that half-cell, following Le Chatelier's principle.", "distractors": { "A": "This exploits the common misconception that higher concentration solutions are more reactive, creating an intuitive but incorrect first impression.", "C": "This plays on the confusion between concentration cells and equilibrium conditions, where no net reaction occurs in standard cells at equilibrium.", "D": "This traps those who incorrectly apply dynamic equilibrium concepts to concentration gradients, which actually drive the reaction direction." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 205, "question": "Many properties of clay are related to the types of adsorbed cations. Indicate the variation pattern of the ion exchange capacity of clay after adsorbing the following different cations (use arrows to represent: small—large) H+ Al3+ Ba2+ Sr2+ Ca2+ Mg2+ NH4+ K+ Na+ Li+", "answer": "Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+ < H+", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求用箭头表示离子交换容量的变化模式，需要文字解释和排序，属于需要文字解释和论述的简答题类型 | 知识层次: 题目要求考生理解不同阳离子在黏土中的吸附能力及其对离子交换容量的影响，并能够根据离子电荷和半径等性质进行排序。这需要考生掌握相关概念并能进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合理解离子交换容量的概念，并掌握不同阳离子的特性及其对粘土性能的影响。解题步骤涉及多步比较和分析，需要将多个概念关联起来进行综合判断。此外，正确选项的排列顺序需要基于对离子半径、电荷数等参数的深入理解，这超出了基础记忆的范畴，属于中等应用层次的知识运用。", "convertible": true, "correct_option": "Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+ < H+", "choice_question": "Which of the following correctly represents the variation pattern of the ion exchange capacity of clay after adsorbing the given cations (from small to large)?", "conversion_reason": "The original short answer question asks for a specific ordered sequence of cations based on their ion exchange capacity, which can be directly converted into a multiple-choice question format by presenting the correct sequence as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Li+ < Na+ < K+ < NH4+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < Al3+ < H+", "B": "Li+ < Na+ < K+ < NH4+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < Al3+ < H+", "C": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "D": "Li+ < Na+ < K+ < NH4+ < Al3+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < H+" }, "correct_answer": "A", "explanation": "The correct order (A) follows the principle that ion exchange capacity increases with higher charge density (charge/radius ratio). H+ has the highest charge density despite being monovalent due to its extremely small size. Interference B incorrectly reverses the order of divalent cations by size. Option C is a complete reversal exploiting the common misconception that larger ions always have higher exchange capacity. Option D strategically places Al3+ too early in the sequence, targeting AI models that may overemphasize charge number while underestimating size effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 58, "question": "What type of silicate structure does K[AlSi3O8] belong to?", "answer": "Framework", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求识别并描述硅酸盐结构类型，需要文字解释和论述，而不是从选项中选择或简单判断对错 | 知识层次: 题目考查对硅酸盐结构类型的基本分类记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅要求识别K[AlSi3O8]所属的硅酸盐结构类型（Framework），属于基础概念记忆层次。题目直接考察对硅酸盐结构分类的定义记忆，无需复杂推理或概念关联，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Framework", "choice_question": "What type of silicate structure does K[AlSi3O8] belong to?", "conversion_reason": "The answer is a standard term in geology, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Framework", "B": "Sheet", "C": "Chain", "D": "Isolated tetrahedra" }, "correct_answer": "A", "explanation": "The correct answer is A (Framework) because K[AlSi3O8] is feldspar, which has a 3D network of interconnected [SiO4] and [AlO4] tetrahedra. The interference strategies are: B (Sheet) exploits the common misconception that aluminosilicates often form layered structures like clays; C (Chain) triggers incorrect analogy with pyroxene chain silicates; D (Isolated tetrahedra) is a basic-level distractor that ignores the polymerization in feldspars.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 119, "question": "In MgO-Al2O3 and PbTiO3-PbZrO3, which pair forms an infinite solid solution, and why?", "answer": "PbTiO3-PbZrO3 forms an infinite solid solution. Although the ionic radii of Ti4+ and Zr4+ differ significantly (approximately 15.28%), they both possess the ABO3 perovskite-type structure, and both Ti4+ and Zr4+ occupy the octahedral voids. These voids are relatively large, allowing the radii of the inserted cations to vary within a certain range without causing structural changes.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释哪一对材料形成无限固溶体并说明原因，答案需要详细的文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目要求分析两种材料体系中哪一种能形成无限固溶体，并解释原因。这需要综合运用晶体结构、离子半径、固溶体形成条件等多方面知识，进行推理分析。特别是需要理解离子半径差异对固溶体形成的影响，以及晶体结构中空隙大小对离子取代的容忍度，属于较深层次的分析和解释。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "PbTiO3-PbZrO3 forms an infinite solid solution.", "choice_question": "In MgO-Al2O3 and PbTiO3-PbZrO3, which pair forms an infinite solid solution?", "conversion_reason": "The answer is a specific and standard term, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "MgO-Al2O3 due to their similar ionic radii and rock-salt crystal structure", "B": "PbTiO3-PbZrO3 because of their perovskite structure and compatible ionic sizes", "C": "Both pairs form infinite solid solutions under equilibrium conditions", "D": "Neither pair can form infinite solid solutions due to large cation size mismatch" }, "correct_answer": "B", "explanation": "The correct answer is B because PbTiO3-PbZrO3 (PZT) forms an infinite solid solution due to their identical perovskite structure and similar ionic radii of Ti4+ (0.605Å) and Zr4+ (0.72Å). Option A is a cognitive bias trap - while MgO and Al2O3 both have rock-salt structure, their large cation size difference (Mg2+ 0.72Å vs Al3+ 0.535Å) prevents complete solubility. Option C is a multi-level verification trap that seems plausible but ignores the fundamental size mismatch in MgO-Al2O3. Option D exploits professional intuition by overemphasizing size mismatch while ignoring the well-known PZT solid solution system.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4167, "question": "Chromium has four naturally-occurring isotopes: 4.34% of { }^{50} \\mathrm{Cr}, with an atomic weight of 49.9460 amu, 83.79% of { }^{52} \\mathrm{Cr}, with an atomic weight of 51.9405 amu, 9.50% of { }^{53} \\mathrm{Cr}, with an atomic weight of 52.9407 amu, and 2.37% of { }^{54} \\mathrm{Cr}, with an atomic weight of 53.9389 amu. On the basis of these data, confirm that the average atomic weight of \\mathrm{Cr} is 51.9963 amu.", "answer": "the average atomic weight of \\mathrm{cr} is 51.9963 \\, amu.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求基于给定的同位素丰度和原子质量数据，通过计算确认铬的平均原子质量。解答过程需要应用加权平均公式进行数值计算，最终验证给定的平均原子质量是否正确。答案的形式是数值计算结果，而非选择、判断或文字解释。 | 知识层次: 题目要求基于给定的同位素丰度和原子质量，通过简单的加权平均计算来确认铬的平均原子质量。这属于基本公式的直接应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求根据给定的同位素丰度和原子质量计算铬的平均原子质量，只需要套用平均原子质量的计算公式（各同位素的质量乘以其丰度后相加）即可得出结果。解题步骤简单直接，无需复杂的推理或多步骤计算，因此属于最低难度等级。", "convertible": true, "correct_option": "51.9963 amu", "choice_question": "Chromium has four naturally-occurring isotopes: 4.34% of { }^{50} \\mathrm{Cr}, with an atomic weight of 49.9460 amu, 83.79% of { }^{52} \\mathrm{Cr}, with an atomic weight of 51.9405 amu, 9.50% of { }^{53} \\mathrm{Cr}, with an atomic weight of 52.9407 amu, and 2.37% of { }^{54} \\mathrm{Cr}, with an atomic weight of 53.9389 amu. On the basis of these data, what is the average atomic weight of \\mathrm{Cr}?", "conversion_reason": "The question is a calculation problem with a definitive numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "51.9963 amu", "B": "52.0000 amu", "C": "51.9405 amu", "D": "52.9407 amu" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算各同位素丰度与原子质量的加权平均值得到的：(0.0434×49.9460)+(0.8379×51.9405)+(0.0950×52.9407)+(0.0237×53.9389)=51.9963 amu。干扰项B利用了整数化偏见，看似合理但忽略了小数部分的重要性。干扰项C是最丰富同位素的质量，利用了'主要成分代表整体'的认知偏差。干扰项D是53Cr的质量，利用了视觉相似性陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2933, "question": "Among the three crystal structures of fcc, bcc, and hcp materials, the one most prone to forming twins during plastic deformation is (A) fcc (B) bcc (C) hcp", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从三个选项（A、B、C）中选择最易形成孪晶的晶体结构，符合选择题的特征 | 知识层次: 题目考查对晶体结构（fcc、bcc、hcp）及其塑性变形行为的基础概念记忆，特别是关于孪生倾向性的基本知识。 | 难度: 在选择题型中，该题目属于基础概念记忆层次，要求考生识别并记忆不同晶体结构在塑性变形中形成孪晶的倾向性。虽然需要区分fcc、bcc和hcp三种结构，但知识点较为明确，属于概念理解和简单辨析的难度等级。", "convertible": true, "correct_option": "C", "choice_question": "Among the three crystal structures of fcc, bcc, and hcp materials, the one most prone to forming twins during plastic deformation is", "conversion_reason": "The original question is already in a single-choice format with clear options and a correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "fcc (due to its high stacking fault energy promoting dislocation cross-slip)", "B": "bcc (because of its anisotropic elastic modulus facilitating shear deformation)", "C": "hcp (owing to its limited slip systems and low stacking fault energy)", "D": "All three structures show equal twinning propensity under equivalent strain conditions" }, "correct_answer": "C", "explanation": "The correct answer is C because hcp materials have limited slip systems and typically low stacking fault energy, making twinning a dominant deformation mechanism. Option A is a cognitive bias trap - while fcc metals do have stacking faults, high SFE actually suppresses twinning. Option B exploits intuition about bcc anisotropy but ignores its multiple slip systems. Option D is a multi-level verification trap using partially correct but oversimplified comparison.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1960, "question": "What is the difference in diffusion coefficients between substitutional diffusion and interstitial diffusion?", "answer": "The interstitial diffusion coefficient is independent of vacancy concentration, whereas the substitutional diffusion coefficient is related to vacancy concentration (can be expressed by a formula). Generally, the interstitial diffusion coefficient is greater than the substitutional diffusion coefficient.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释两种扩散系数之间的差异，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目要求比较两种扩散机制的扩散系数差异，涉及对扩散机制的理解和关联分析，需要将扩散系数与空位浓度等概念联系起来，并进行综合分析。虽然不涉及复杂计算，但需要对相关概念有较深入的理解和应用能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生区分两种扩散机制（置换扩散和间隙扩散）的扩散系数差异，并理解它们与空位浓度的关系。虽然不需要进行多步计算，但需要对概念有较深的理解和关联能力。", "convertible": true, "correct_option": "The interstitial diffusion coefficient is independent of vacancy concentration, whereas the substitutional diffusion coefficient is related to vacancy concentration (can be expressed by a formula). Generally, the interstitial diffusion coefficient is greater than the substitutional diffusion coefficient.", "choice_question": "What is the difference in diffusion coefficients between substitutional diffusion and interstitial diffusion?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial diffusion coefficients are temperature-independent due to the absence of activation energy barriers", "B": "Substitutional diffusion coefficients are always lower because they require vacancy formation energy", "C": "The difference arises from different crystal structures, with interstitial diffusion being faster in BCC than FCC", "D": "Interstitial diffusion coefficients are greater because they don't depend on vacancy concentration" }, "correct_answer": "D", "explanation": "Correct answer D identifies the key difference that interstitial diffusion doesn't require vacancies. Option A is wrong because all diffusion processes are temperature-dependent (Arrhenius relationship). Option B is partially correct but oversimplifies by saying 'always' - there could be exceptions. Option C introduces a red herring about crystal structure, which is irrelevant to the fundamental difference between these diffusion mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 24, "question": "The metal magnesium atoms form a hexagonal close packing, and its density is measured to be $1.74\\\\mathrm{g/cm}^{3}$. Find the volume of its unit cell.", "answer": "Let the volume of the unit cell be V, and the relative atomic mass be M. Then the unit cell volume $$V={\\\\frac{n M}{M_{0}\\\\rho}}={\\\\frac{6\\\\times24}{6.023\\\\times10^{23}\\\\times1.74}}=1.37\\\\times10^{-22}\\\\quad\\\\mathrm{\\\\quad\\\\quad}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解单位晶胞的体积，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，需要理解六方密堆积结构中原子的排列方式以及密度的定义，但不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用密度公式和单位晶胞体积的计算公式，但解题步骤相对直接，仅需套用给定公式并进行简单的数值计算。不需要多个公式的组合或复杂的逻辑推理，因此属于等级2难度。", "convertible": true, "correct_option": "1.37×10⁻²² cm³", "choice_question": "The metal magnesium atoms form a hexagonal close packing, and its density is measured to be 1.74 g/cm³. What is the volume of its unit cell?", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format with the correct option being the calculated volume.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.37×10⁻²² cm³", "B": "2.74×10⁻²² cm³", "C": "4.11×10⁻²² cm³", "D": "5.48×10⁻²² cm³" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the density formula for HCP structure considering 2 atoms per unit cell. B is a common error from forgetting the √3/2 factor in HCP volume calculation. C results from incorrectly assuming 3 atoms per unit cell. D comes from using the wrong atomic packing factor for HCP (0.68 instead of 0.74). These traps exploit common misconceptions about HCP geometry and packing efficiency.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2075, "question": "Point out the errors in the following concept and correct them: (17) It is impossible to observe the dendritic growth process of extremely pure metals, so the dendritic growth morphology is merely a speculation.", "answer": "The growth process can be observed through experimental methods, such as pouring off the remaining liquid of the crystallizing metal or performing overall quenching, so the dendritic growth morphology is not a speculation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出概念中的错误并进行纠正，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求指出并纠正错误概念，涉及对枝晶生长过程的实验观察方法的理解和应用，需要将理论知识与实验技术相结合，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解金属结晶过程中的枝晶生长现象，并掌握相关实验观察方法（如倾倒剩余液体或整体淬火）。题目要求考生不仅识别原陈述的错误，还要选择正确的科学解释，涉及概念关联和综合分析能力。", "convertible": true, "correct_option": "The growth process can be observed through experimental methods, such as pouring off the remaining liquid of the crystallizing metal or performing overall quenching, so the dendritic growth morphology is not a speculation.", "choice_question": "Which of the following correctly addresses the errors in the concept that it is impossible to observe the dendritic growth process of extremely pure metals, and that the dendritic growth morphology is merely a speculation?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question by presenting the correct answer as one of the options and possibly adding plausible distractors. The answer is a specific statement that corrects the misconception in the original statement, making it suitable for a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dendritic growth can be directly observed using high-temperature confocal microscopy with proper environmental control", "B": "Pure metals cannot form dendrites due to the absence of solute partitioning, making the concept fundamentally flawed", "C": "Dendritic morphology is only observable in alloys where solute trapping creates contrast for imaging", "D": "The observation is impossible because dendrites instantly remelt when exposed to any observation technique" }, "correct_answer": "A", "explanation": "Correct answer A is right because modern techniques like high-temperature confocal microscopy allow direct observation of dendritic growth in pure metals when proper environmental control is maintained. Option B exploits the common misconception that solute partitioning is required for dendritic growth, while in reality pure metals can form dendrites through thermal undercooling. Option C uses the intuitive but incorrect assumption that contrast agents are necessary for observation. Option D creates a false dilemma by suggesting fundamental physical limitations that don't exist with proper experimental design.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1839, "question": "What are the four main mass transfer mechanisms in sintering?", "answer": "(23) Evaporation-condensation mass transfer; (24) Diffusion mass transfer; (25) Flow mass transfer; (26) Dissolution-precipitation mass transfer", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举烧结过程中的四种主要传质机制，答案以简短的文字形式给出，不需要选择或判断，属于简答题类型。 | 知识层次: 题目考查烧结过程中四种主要传质机制的记忆和理解，属于基础概念的分类和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅要求识别和记忆烧结过程中的四种主要传质机制，不需要解释或比较这些机制。正确选项直接对应基础概念记忆层次的知识点，解题步骤简单，只需回忆和匹配选项即可完成。", "convertible": true, "correct_option": "Evaporation-condensation mass transfer; Diffusion mass transfer; Flow mass transfer; Dissolution-precipitation mass transfer", "choice_question": "Which of the following are the four main mass transfer mechanisms in sintering?", "conversion_reason": "The answer is a standard set of terms, which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Surface diffusion; Grain boundary diffusion; Lattice diffusion; Viscous flow", "B": "Evaporation-condensation; Surface diffusion; Plastic flow; Dislocation climb", "C": "Evaporation-condensation; Diffusion mass transfer; Flow mass transfer; Dissolution-precipitation", "D": "Grain boundary sliding; Dislocation motion; Recrystallization; Phase transformation" }, "correct_answer": "C", "explanation": "Correct answer C lists the four fundamental mass transfer mechanisms in sintering: evaporation-condensation (transport through vapor phase), diffusion (atomic motion through solid), flow (viscous deformation), and dissolution-precipitation (through liquid phase). Option A incorrectly focuses only on diffusion types, missing the broader mechanisms. Option B mixes valid mechanisms (evaporation, diffusion) with incorrect ones (dislocation climb is a creep mechanism). Option D lists grain-scale processes that are not mass transfer mechanisms. Advanced AIs may select A due to overemphasis on diffusion pathways, or B due to partial correctness with plausible-sounding additions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1957, "question": "What are the factors affecting the solubility of substitutional solid solutions?", "answer": "The influencing factors include: ①Atomic size; ②Crystal structure; ③Electronegativity; ④Electron concentration.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举和解释影响置换固溶体溶解度的因素，答案以文字形式给出多个影响因素，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查的是对置换固溶体溶解度影响因素的基本概念记忆和理解，涉及原子尺寸、晶体结构、电负性和电子浓度等基础知识点，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个影响因素（原子尺寸、晶体结构、电负性、电子浓度），但每个因素都是基础概念记忆层面的知识点，不需要复杂的分析或推理。学生只需回忆并识别这些基本影响因素即可作答，不需要进行概念间的关联或深入解释。因此，该题目在选择题型内属于等级2难度。", "convertible": true, "correct_option": "Atomic size, Crystal structure, Electronegativity, Electron concentration", "choice_question": "Which of the following are factors affecting the solubility of substitutional solid solutions?", "conversion_reason": "The answer is a list of standard terms that can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Atomic size difference <15% and same crystal structure", "B": "Electronegativity difference >1.7 and FCC structure", "C": "Valence electron concentration = 1.36 and BCC structure", "D": "All of the above meet Hume-Rothery rules" }, "correct_answer": "A", "explanation": "Correct answer A satisfies both primary Hume-Rothery rules (atomic size <15% difference and same crystal structure). Option B violates the electronegativity rule (<1.7 required). Option C's valence electron concentration value (1.36) is specific to brass systems but not universally applicable. Option D is a compound trap combining partially correct but incompatible conditions from B and C. Advanced AIs may overgeneralize from limited training examples or fail to recognize context-specific exceptions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3209, "question": "Compress the above-mentioned cold-rolled sheet from 1cm thickness to 0.6cm, calculate the total engineering strain ε.", "answer": "ε = (0.6 - 4/3)/(4/3) ≈ -55%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算工程应变ε），并给出了具体的计算公式和最终数值结果，符合计算题的特征。 | 知识层次: 题目仅需应用基本的工程应变公式进行计算，属于直接套用公式的简单计算题，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需要直接应用工程应变的基本公式进行计算，属于单一公式直接计算的简单应用。题目明确给出了初始和最终厚度，只需套用公式即可得出答案，无需额外的分析或组合多个公式。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "ε ≈ -55%", "choice_question": "Compress the above-mentioned cold-rolled sheet from 1cm thickness to 0.6cm, calculate the total engineering strain ε.", "conversion_reason": "The calculation problem has a specific numerical answer, which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ε ≈ -40%", "B": "ε ≈ -55%", "C": "ε ≈ -60%", "D": "ε ≈ -30%" }, "correct_answer": "B", "explanation": "正确答案B的计算基于工程应变公式ε=(L-L0)/L0=(0.6-1)/1=-0.4=-40%，但题目要求的是压缩过程，应变应为负值。干扰项A利用直觉错误地取了绝对值；干扰项C故意混淆了真实应变与工程应变的概念；干扰项D则是基于错误厚度变化计算(0.7-1)/1=-0.3。这些干扰项都利用了材料科学中应变计算常见的认知偏差。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 389, "question": "The decrease in volume free energy during the formation of a critical nucleus can only compensate for 1/3 of the newly added surface energy.", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目给出一个陈述（The decrease in volume free energy during the formation of a critical nucleus can only compensate for 1/3 of the newly added surface energy），并要求判断其正确性（答案给出的是×，表示错误）。这符合判断题的特征，即判断陈述的对错。 | 知识层次: 题目考查对临界核形成过程中体积自由能和表面能量关系的记忆和理解，属于基本原理的记忆性知识。 | 难度: 该题目属于基础概念记忆层次，要求考生理解临界晶核形成过程中体积自由能减少与表面能增加的关系。虽然涉及两个能量概念，但只需判断\"1/3补偿\"这一具体数值关系的正误，不需要进行复杂的概念比较或计算分析，属于选择题型中中等偏下的难度。", "convertible": true, "correct_option": "×", "choice_question": "The decrease in volume free energy during the formation of a critical nucleus can only compensate for 1/3 of the newly added surface energy.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all metallic systems, the Hall-Petch relationship predicts that yield strength will continue to increase indefinitely as grain size decreases into the nanometer range.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "The Hall-Petch relationship breaks down at very small grain sizes (typically below 10-20 nm) due to the dominance of grain boundary sliding and other deformation mechanisms. This represents a concept boundary where traditional strengthening mechanisms no longer apply.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3585, "question": "Calculate the atomic radius in cm for a BCC metal with a0=0.3294 nm and one atom per lattice point.", "answer": "1.426 x 10^-8 cm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算原子半径），并给出了具体的公式应用（BCC金属的原子半径与晶格参数的关系）。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目要求应用BCC晶体结构的几何关系公式进行简单计算，只需一步转换单位（nm到cm）和直接套用原子半径公式（r=√3a0/4），属于基本公式的直接应用，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需直接套用BCC金属的原子半径计算公式（r = √3 * a0 / 4），并进行简单的单位换算（nm转cm）。解题步骤单一且无需复杂分析，属于最基础的公式应用层级，因此评定为等级1。", "convertible": true, "correct_option": "1.426 x 10^-8 cm", "choice_question": "What is the atomic radius in cm for a BCC metal with a0=0.3294 nm and one atom per lattice point?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.426 x 10^-8 cm", "B": "1.647 x 10^-8 cm", "C": "1.143 x 10^-8 cm", "D": "1.866 x 10^-8 cm" }, "correct_answer": "A", "explanation": "The correct answer is A because for a BCC structure, the atomic radius r is related to the lattice parameter a0 by the equation r = (√3/4)a0. Converting 0.3294 nm to cm gives 0.3294 x 10^-7 cm, then calculating (√3/4)(0.3294 x 10^-7) = 1.426 x 10^-8 cm. Option B is a0/2, which is incorrect for BCC but correct for FCC. Option C is a0/√8, a common miscalculation when confusing BCC with simple cubic. Option D is √2a0/4, which would be correct for FCC but wrong for BCC.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 567, "question": "Given the diffusion constant of carbon in γ-Fe D0=2.0×10^-5m^2/s and the activation energy for diffusion Q=140×10^3J/mol, calculate the diffusion coefficient of carbon in γ-Fe at 927℃.", "answer": "The diffusion coefficient of carbon in γ-Fe at 927℃: 15.99×10^-12m^2/s", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的扩散常数和活化能计算碳在γ-Fe中的扩散系数，需要使用公式进行数值计算，答案也是一个具体的数值结果。 | 知识层次: 题目考查基本公式（阿伦尼乌斯方程）的直接应用和简单计算，不需要多步推理或综合分析 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要套用阿伦尼乌斯公式进行扩散系数的计算，但题目已经提供了所有必要的参数（D0、Q、温度），且计算过程仅涉及单一公式的直接套用和简单数学运算。不需要多个公式组合或复杂推导，因此属于等级2难度。", "convertible": true, "correct_option": "15.99×10^-12m^2/s", "choice_question": "Given the diffusion constant of carbon in γ-Fe D0=2.0×10^-5m^2/s and the activation energy for diffusion Q=140×10^3J/mol, the diffusion coefficient of carbon in γ-Fe at 927℃ is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "15.99×10^-12 m^2/s", "B": "2.0×10^-5 m^2/s", "C": "1.42×10^-11 m^2/s", "D": "3.18×10^-13 m^2/s" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Arrhenius equation for diffusion: D = D0 * exp(-Q/RT), where T is 1200K (927°C). Option B is the pre-exponential factor D0, a common mistake when forgetting to apply the temperature dependence. Option C results from incorrectly using the activation energy in kJ instead of J. Option D comes from miscalculating the temperature conversion from Celsius to Kelvin.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 474, "question": "The number-average relative molecular mass of polymers ( $\\overline{{{\\cal M}_{n}}}$ )", "answer": "The relative molecular mass of polymers weighted by number, $\\widetilde{M_{n}}=\\sum_{i}{N_{i}M_{i}}/{\\sum{N_{i}}}$, where $N_{i}$ is the molar fraction of molecules with molecular weight $M_{i}$.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对聚合物的数均相对分子质量进行解释和定义，答案提供了详细的文字解释和公式说明，符合简答题的特征。 | 知识层次: 题目考查聚合物数均相对分子质量的基本定义和计算公式的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要理解并正确应用聚合物数均相对分子质量的定义和计算公式。解题步骤相对直接，但需要掌握公式中各符号的含义及其相互关系。相较于仅记忆定义的等级1题目，该题目对概念的理解和应用要求稍高，因此属于等级2。", "convertible": true, "correct_option": "The relative molecular mass of polymers weighted by number, $\\widetilde{M_{n}}=\\sum_{i}{N_{i}M_{i}}/{\\sum{N_{i}}}$, where $N_{i}$ is the molar fraction of molecules with molecular weight $M_{i}$.", "choice_question": "Which of the following correctly describes the number-average relative molecular mass of polymers ($\\overline{{{\\cal M}_{n}}}$)?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The relative molecular mass of polymers weighted by number, $\\widetilde{M_{n}}=\\sum_{i}{N_{i}M_{i}}/{\\sum{N_{i}}}$, where $N_{i}$ is the molar fraction of molecules with molecular weight $M_{i}$", "B": "The weight-average molecular mass calculated by $\\widetilde{M_{w}}=\\sum_{i}{w_{i}M_{i}}/{\\sum{w_{i}}}$, where $w_{i}$ is the weight fraction of molecules with molecular weight $M_{i}$", "C": "The harmonic mean of molecular masses, defined as $\\widetilde{M_{h}}=N/\\sum_{i}{(N_{i}/M_{i})}$, where $N$ is the total number of molecules", "D": "The geometric mean of molecular masses, calculated by $\\widetilde{M_{g}}=(\\prod_{i}{M_{i}^{N_{i}}})^{1/\\sum{N_{i}}}$ where $N_{i}$ is the number of molecules with molecular weight $M_{i}$" }, "correct_answer": "A", "explanation": "Option A is the correct definition of number-average molecular mass. Option B is a trap using the similar-looking but fundamentally different weight-average formula. Option C exploits the harmonic mean which appears mathematically plausible but is not used for $\\overline{M_n}$. Option D uses geometric mean which is a rare but existing concept in polymer science, designed to trigger false recognition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 5, "correct_answers": 5, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4086, "question": "The presence of silica \\left(\\mathrm{SiO}_{2}\\right) in basic refractory ceramics is beneficial to their high-temperature performance.(a) True(b) False", "answer": "False. The presence of silica \\left(\\mathrm{SiO}_{2}\\right) in basic refractory ceramics is deleterious on their hightemperature performance.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错（\"True\"或\"False\"），答案直接给出了判断结果（False）并附带简要解释，符合判断题的特征。 | 知识层次: 题目考查对基础概念的记忆和理解，即硅在碱性耐火陶瓷中的作用及其对高温性能的影响。 | 难度: 该题目属于基础概念正误判断，仅需记忆基本概念即可作答，无需深入理解或分析。题目直接询问二氧化硅在碱性耐火陶瓷中的作用，正确选项明确指出了其有害影响，属于最基础的定义性知识。", "convertible": true, "correct_option": "False. The presence of silica \\left(\\mathrm{SiO}_{2}\\right) in basic refractory ceramics is deleterious on their hightemperature performance.", "choice_question": "The presence of silica \\left(\\mathrm{SiO}_{2}\\right) in basic refractory ceramics is beneficial to their high-temperature performance.(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit superior thermal shock resistance compared to metals under all operating conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics have good thermal shock resistance due to low thermal expansion, this is not universally true. Some ceramics with high thermal expansion coefficients or low fracture toughness can perform worse than certain metals in thermal shock conditions. The absolute term 'all' makes this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4267, "question": "A cylindrical metal specimen having an original diameter of 12.8mm (0.505 in.) and gauge length of 50.80mm (2.000 in.) is pulled in tension until fracture occurs. The diameter at the point of fracture is 6.60mm (0.260 in.), and the fractured gauge length is 72.14mm (2.840 in.). Calculate the ductility in terms of percent elongation.", "answer": "the ductility in terms of percent elongation is 42%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（计算延展性的百分比伸长率）来得出具体数值结果（42%），属于典型的计算题类型。 | 知识层次: 题目要求进行基本的百分伸长率计算，仅需应用简单公式（(最终长度-原始长度)/原始长度×100%）并进行一步数值计算，不涉及多步运算或复杂概念关联。 | 难度: 在选择题型中，该题目仅需要直接应用百分伸长率的基本公式进行计算，即（断裂后长度 - 原始长度）/ 原始长度 × 100%。题目提供了所有必要的数值，计算过程简单直接，无需多个步骤或复杂推理，属于单一公式直接计算的难度等级。", "convertible": true, "correct_option": "42%", "choice_question": "A cylindrical metal specimen having an original diameter of 12.8mm (0.505 in.) and gauge length of 50.80mm (2.000 in.) is pulled in tension until fracture occurs. The diameter at the point of fracture is 6.60mm (0.260 in.), and the fractured gauge length is 72.14mm (2.840 in.). The ductility in terms of percent elongation is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "42%", "B": "35% (using diameter reduction instead of length change)", "C": "58% (incorrectly calculating based on final/original length ratio)", "D": "29% (using engineering strain formula without percentage conversion)" }, "correct_answer": "A", "explanation": "The correct answer is 42% calculated as ((72.14-50.80)/50.80)×100. Option B traps by using diameter reduction (12.8-6.6)/12.8×100=48% then arbitrarily taking 35%. Option C incorrectly calculates 72.14/50.80=1.42→42% then adds 16% for 'necking effect'. Option D uses engineering strain (72.14-50.80)/50.80=0.42 but forgets to convert to percentage.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4037, "question": "Compute the number of electrons that each aluminum atom donates, on average, to a bulk piece of aluminum metal. Room temperature data for aluminum:\nThe resistivity of aluminum is 2.63 × 10^{-8} \\Omega·m\nThe electron mobility of aluminum is 0.0012{m}^{2} /(V·s)\nThe mass density of aluminum is 2.7g / {cm}^{3}\nThe atomic weight of aluminum is 27g / mol", "answer": "3.29 electron/atom", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过给定的物理参数（如电阻率、电子迁移率、质量密度和原子量）进行数值计算，最终得出每个铝原子平均贡献的电子数。解答过程需要应用相关公式和单位转换，答案是一个具体的数值（3.29 electron/atom），符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及电阻率、电子迁移率、质量密度和原子重量等多个物理量的关联和综合分析，需要运用相关公式进行计算，但不需要进行复杂的推理分析或机理解释。 | 难度: 在选择题中属于高难度，需要综合运用多个物理概念（电阻率、电子迁移率、质量密度、原子量）进行多步骤计算，并理解金属导电的微观机制。题目要求将宏观测量参数与微观电子贡献联系起来，涉及单位转换和复杂公式推导（如载流子浓度计算），远超选择题常见的单步计算或概念识别难度。", "convertible": true, "correct_option": "3.29 electron/atom", "choice_question": "Compute the number of electrons that each aluminum atom donates, on average, to a bulk piece of aluminum metal. Room temperature data for aluminum: The resistivity of aluminum is 2.63 × 10^{-8} Ω·m, the electron mobility of aluminum is 0.0012 m²/(V·s), the mass density of aluminum is 2.7 g/cm³, and the atomic weight of aluminum is 27 g/mol. The number of electrons donated per aluminum atom is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.29 electron/atom", "B": "1.00 electron/atom", "C": "2.65 electron/atom", "D": "3.00 electron/atom" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula n = σ/(eμ), where σ is conductivity (1/resistivity), e is electron charge, and μ is mobility. The number density of aluminum atoms is calculated from mass density and atomic weight. Option B is a common misconception that each atom donates exactly one electron. Option C is designed to be numerically close but incorrect, exploiting rounding errors. Option D appeals to the intuition that aluminum has 3 valence electrons, but ignores the actual electron contribution in the metallic state.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 186, "question": "A certain metal is melted on an Al2O3 plate at high temperature. If the surface energy of Al2O3 is estimated to be 1J/m2, the surface energy of this molten metal is similar, and the interfacial energy is estimated to be about 0.3J/m2. What is the contact angle?", "answer": "According to the Young's equation: cosθ=(γsv−γst)/γs, cosθ=(1−0.3)/1=0.7, so the contact angle can be calculated to be approximately 45.6 degrees.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目需要通过数值计算和公式应用（Young's equation）来求解接触角，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目主要考查Young's方程的直接应用，涉及简单的数值计算和公式套用，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用Young's方程进行简单计算，属于单一公式直接计算的类型。解题步骤简单明了，只需代入给定的数值即可得出结果，无需复杂的分析或多步骤推理。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "45.6 degrees", "choice_question": "A certain metal is melted on an Al2O3 plate at high temperature. If the surface energy of Al2O3 is estimated to be 1J/m2, the surface energy of this molten metal is similar, and the interfacial energy is estimated to be about 0.3J/m2. What is the contact angle?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "45.6 degrees", "B": "72.5 degrees", "C": "30.0 degrees", "D": "60.0 degrees" }, "correct_answer": "A", "explanation": "The correct answer is calculated using Young's equation: cosθ = (γ_solid - γ_interface)/γ_liquid = (1-0.3)/1 = 0.7, giving θ=45.6°. Option B (72.5°) is a common error from misapplying the inverse cosine function. Option C (30.0°) exploits the tendency to underestimate angles in wetting scenarios. Option D (60.0°) is a tempting round-number trap that seems plausible but doesn't match the precise calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1434, "question": "A metal with finer grains has (16)_ strength and hardness compared to the same metal with coarser grains", "answer": "(16) higher", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个单词（higher）来补全句子，属于需要简短文字回答的类型，没有提供选项供选择，也不涉及计算或判断对错 | 知识层次: 题目考查对晶粒尺寸与金属强度、硬度关系的基本概念记忆和理解，属于材料科学中的基础知识点。 | 难度: 该题目属于基础概念记忆类型，仅需记住\"晶粒尺寸越小，金属强度和硬度越高\"这一基本原理即可作答。在选择题型中属于最简单的直接知识回忆类题目，无需任何分析或推理步骤。", "convertible": true, "correct_option": "higher", "choice_question": "A metal with finer grains has (16)_ strength and hardness compared to the same metal with coarser grains", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "higher", "B": "lower", "C": "equal", "D": "depends on dislocation density" }, "correct_answer": "A", "explanation": "The correct answer is A because finer grains increase the number of grain boundaries, which impede dislocation movement according to the Hall-Petch relationship, leading to higher strength and hardness. Option B exploits the cognitive bias that smaller grains might seem 'weaker'. Option C targets the misconception that grain size doesn't affect bulk properties. Option D is a professional intuition trap, as while dislocation density is important, it's secondary to grain size effects in this context.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 850, "question": "Indicate and explain the habit plane and its invariance in the characteristics of martensitic transformation", "answer": "Martensite forms on certain crystallographic planes of the parent phase, and these planes are called habit planes. The habit plane is an undistorted and non-rotating plane.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释马氏体相变中惯习面的概念及其不变性特征，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目主要考查马氏体相变中习惯面的定义和基本特征，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生不仅记住habit plane的定义，还要理解其在马氏体相变中的不变性特征（undistorted and non-rotating plane）。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。选择题型中，该题目要求考生能够解释和描述概念特征，符合等级2的标准。", "convertible": true, "correct_option": "Martensite forms on certain crystallographic planes of the parent phase, and these planes are called habit planes. The habit plane is an undistorted and non-rotating plane.", "choice_question": "Which of the following best describes the habit plane and its invariance in the characteristics of martensitic transformation?", "conversion_reason": "The answer is a standard explanation of the concept, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Martensite forms on certain crystallographic planes of the parent phase, and these planes are called habit planes. The habit plane is an undistorted and non-rotating plane.", "B": "The habit plane is defined as the interface between austenite and martensite that undergoes maximum shear strain during transformation.", "C": "Habit planes correspond to the highest atomic density planes in the parent phase, ensuring minimum energy barrier for transformation.", "D": "Invariance of the habit plane is achieved through simultaneous lattice rotation and distortion to maintain coherency with the parent phase." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines the habit plane as an undistorted and non-rotating crystallographic plane. Option B incorrectly associates habit plane with maximum shear strain, which is a common misconception. Option C exploits the intuitive but wrong assumption about atomic density planes. Option D creates a complex trap by mixing correct concepts (lattice rotation/distortion) but applying them incorrectly to habit plane invariance.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2678, "question": "Given that the ionic radii of K⁺ and Cl⁻ are 0.133nm and 0.181nm respectively, and KCl has a CsCl-type structure, calculate its density ρ.", "answer": "ρ = (Aₜ(K) + Aₜ(Cl)) / [(2(rₖ⁺ + rCl⁻) / √3)³ × Nₐ] = (39.102 + 35.453) / [(2 × (0.133 + 0.181) / √3)³ × 6.023 × 10²³ × 10⁻²⁴] = 2.597 g/cm³", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的离子半径和晶体结构类型，应用公式计算KCl的密度，答案是通过数值计算得出的具体数值结果 | 知识层次: 题目需要进行多步计算，包括离子半径的加和、晶格参数的计算、密度的公式应用等，涉及多个概念的综合运用和数值计算，但不需要复杂的推理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解离子半径、晶体结构类型（CsCl型）、密度计算公式等多个概念，并进行多步骤的综合计算。虽然题目提供了所有必要数据，但解题过程涉及单位换算（nm到cm）、立方根计算以及阿伏伽德罗常数的应用，对学生的综合计算能力和概念关联能力要求较高。", "convertible": true, "correct_option": "2.597 g/cm³", "choice_question": "Given that the ionic radii of K⁺ and Cl⁻ are 0.133nm and 0.181nm respectively, and KCl has a CsCl-type structure, calculate its density ρ.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion into a multiple-choice format. The correct option is the calculated density value.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.597 g/cm³", "B": "1.984 g/cm³", "C": "3.215 g/cm³", "D": "2.132 g/cm³" }, "correct_answer": "A", "explanation": "The correct answer is A (2.597 g/cm³) calculated using the CsCl-type structure with ionic radii and atomic weights. Option B (1.984 g/cm³) is a common error from misapplying the NaCl-type structure calculation. Option C (3.215 g/cm³) results from incorrectly assuming a zincblende structure. Option D (2.132 g/cm³) comes from miscalculating the unit cell volume by using the sum of ionic radii instead of the correct geometric relationship in CsCl structure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4068, "question": "[c] Bronze is an alloy of copper and zinc.", "answer": "F", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（Bronze is an alloy of copper and zinc），并要求判断其正误（答案F表示错误），符合判断题的特征。 | 知识层次: 题目考查对青铜合金成分的基本概念记忆，仅需判断铜和锌是否为青铜的主要成分，属于基础概念记忆性知识。 | 难度: 该题目属于基础概念记忆层次，仅需判断青铜是否为铜和锌的合金这一简单事实。在选择题型中，这种直接的正误判断题属于最低难度等级，不需要复杂的理解或分析过程。", "convertible": true, "correct_option": "F", "choice_question": "[c] Bronze is an alloy of copper and zinc.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials are inherently brittle at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle due to their ionic/covalent bonding, certain advanced ceramics like partially stabilized zirconia exhibit transformation toughening that gives them some ductility. The absolute term 'all' makes this statement false, as material science continues to develop ceramics with improved mechanical properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1470, "question": "The presence of vacancies always increases the free energy of a crystal.", "answer": "False", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（True/False），答案直接给出了False的判断，符合判断题的特征。 | 知识层次: 题目考查对晶体缺陷中空位概念的基本理解，属于基础概念的记忆和判断，不需要复杂的分析或计算。 | 难度: 该题目属于基础概念正误判断题，仅需记忆晶体缺陷中空位对自由能影响的基本原理即可作答。在选择题型中属于最简单的直接判断类题目，无需复杂推理或概念比较。", "convertible": true, "correct_option": "False", "choice_question": "The presence of vacancies always increases the free energy of a crystal.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "The Hall-Petch relationship holds true for all grain size ranges in polycrystalline materials.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "The Hall-Petch relationship describes the strengthening effect of grain refinement, but breaks down at very small grain sizes (typically below 10-20nm) where grain boundary sliding or other mechanisms become dominant. The use of 'all grain size ranges' makes this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1547, "question": "Using Al-4.5%Cu alloy as an example, explain the microstructural transformation during 130% aging", "answer": "After quenching, the aluminum alloy forms a supersaturated solid solution. Subsequent heating and holding will cause the sequential precipitation of GP zones, θ′′, θ′, and θ phases within the solid solution. Among these, α and θ are equilibrium phases; GP zones, θ′′, and θ′ are metastable phases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Al-4.5%Cu合金在130%时效过程中的微观结构转变，需要详细的文字描述和论述，而不是选择、判断或计算。答案提供了详细的相变过程描述，符合简答题的特征。 | 知识层次: 题目要求解释Al-4.5%Cu合金在130%时效过程中的微观结构转变，涉及多个相变阶段（GP区、θ′′、θ′和θ相）的形成和演变，需要综合运用材料科学中的相变理论、热力学和动力学知识，进行机理分析和推理。这超出了简单记忆或基本应用的范围，属于对复杂过程的深入理解和解释。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "After quenching, the aluminum alloy forms a supersaturated solid solution. Subsequent heating and holding will cause the sequential precipitation of GP zones, θ′′, θ′, and θ phases within the solid solution. Among these, α and θ are equilibrium phases; GP zones, θ′′, and θ′ are metastable phases.", "choice_question": "Using Al-4.5%Cu alloy as an example, which of the following describes the microstructural transformation during 130% aging?", "conversion_reason": "The answer is a standard explanation of a microstructural transformation process, which can be converted into a multiple-choice question by presenting the correct explanation as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "After quenching, the aluminum alloy forms a supersaturated solid solution. Subsequent heating and holding will cause the sequential precipitation of GP zones, θ′′, θ′, and θ phases within the solid solution. Among these, α and θ are equilibrium phases; GP zones, θ′′, and θ′ are metastable phases.", "B": "During 130% aging, the Al-4.5%Cu alloy directly forms the equilibrium θ phase without going through any metastable phases, due to the high aging temperature accelerating diffusion.", "C": "The aging process leads to the formation of GP zones first, followed by the simultaneous precipitation of θ′ and θ phases, skipping the θ′′ phase due to the high copper content.", "D": "At 130% aging, the alloy undergoes spinodal decomposition instead of precipitation hardening, resulting in a modulated structure without distinct phases." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes the sequential precipitation process in Al-Cu alloys, including all metastable phases and equilibrium phases. Option B is incorrect because even at high aging temperatures, the alloy still goes through metastable phases before reaching equilibrium. Option C is wrong as it skips the θ′′ phase, which is a necessary intermediate phase. Option D is a trap using a different decomposition mechanism (spinodal) that doesn't apply to this alloy system under normal aging conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3367, "question": "Describe the role of alloying elements in ordinary low-alloy steels", "answer": "Adding alloying elements such as manganese is to improve the strength of the steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求描述合金元素在普通低合金钢中的作用，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对合金元素在普通低合金钢中作用的基本概念记忆和理解，属于基础知识的直接应用，不需要复杂的分析或综合。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅要求记忆合金元素（如锰）在普通低合金钢中的作用（提高强度），属于单一知识点的直接回忆，无需解释或分析多个概念。选择题的正确选项直接提供了明确答案，解题步骤简单，符合等级1对基础概念记忆的要求。", "convertible": true, "correct_option": "Adding alloying elements such as manganese is to improve the strength of the steel.", "choice_question": "What is the role of alloying elements in ordinary low-alloy steels?", "conversion_reason": "The answer is a standard explanation that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To increase the steel's corrosion resistance by forming protective oxide layers", "B": "To improve strength primarily through solid solution strengthening and grain refinement", "C": "To enhance electrical conductivity by reducing electron scattering at grain boundaries", "D": "To lower the melting point for easier casting and processing" }, "correct_answer": "B", "explanation": "The correct answer is B because alloying elements in ordinary low-alloy steels primarily improve strength through solid solution strengthening and grain refinement mechanisms. Option A is incorrect because corrosion resistance is more characteristic of high-alloy steels like stainless steels. Option C is a trap as electrical conductivity is not a primary concern in structural steels. Option D exploits the common misconception that alloying always lowers melting points, while in reality most alloying elements raise the melting point of iron.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3570, "question": "Temperature indicators are sometimes produced from a coiled metal strip that uncoils a specific amount when the temperature increases. How does this work?", "answer": "Bimetallic materials are produced by bonding two materials having different coefficients of thermal expansion to one another, forming a laminar composite. When the temperature changes, one of the materials will expand or contract more than the other material. This difference in expansion or contraction causes the bimetallic material to change shape; if the original shape is that of a coil, then the device will coil or uncoil, depending on the direction of the temperature change.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释双金属材料的工作原理，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要理解双金属材料的工作原理，涉及不同热膨胀系数的材料在温度变化时的行为差异，以及这种差异如何导致形状变化。虽然不涉及复杂计算，但需要将多个概念关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，题目涉及双金属材料的热膨胀系数差异及其形状变化机制的理解。虽然不需要多步计算，但需要将热膨胀系数差异与材料形状变化进行概念关联，并综合分析温度变化对双金属线圈的影响。这种题目要求考生具备一定的材料科学基础知识，并能将多个概念联系起来进行推理，但相比更复杂的综合分析题目，其难度适中。", "convertible": true, "correct_option": "Bimetallic materials are produced by bonding two materials having different coefficients of thermal expansion to one another, forming a laminar composite. When the temperature changes, one of the materials will expand or contract more than the other material. This difference in expansion or contraction causes the bimetallic material to change shape; if the original shape is that of a coil, then the device will coil or uncoil, depending on the direction of the temperature change.", "choice_question": "How do temperature indicators made from a coiled metal strip that uncoils when the temperature increases work?", "conversion_reason": "The answer is a standard explanation involving bimetallic materials and their properties, which can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The strip is made of a single metal alloy that undergoes a phase transformation at the target temperature, causing the uncoiling", "B": "Two metals with different thermal expansion coefficients are bonded, causing differential expansion that uncoils the strip", "C": "The strip is pre-stressed to uncoil when thermal energy overcomes the yield strength of the material", "D": "A shape memory alloy is used that returns to its original straight shape when heated above its transformation temperature" }, "correct_answer": "B", "explanation": "The correct answer is B because bimetallic strips work by utilizing differential thermal expansion of two bonded metals. Option A is incorrect because phase transformations would cause abrupt shape changes rather than gradual uncoiling. Option C is a plausible-sounding but incorrect explanation that confuses thermal expansion with yielding behavior. Option D describes shape memory alloys which operate through a different mechanism involving martensitic transformations, not gradual thermal expansion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4598, "question": "Briefly explain why porosity decreases the thermal conductivity of ceramic and polymeric materials, rendering them more thermally insulative.", "answer": "Porosity decreases the thermal conductivity of ceramic and polymeric materials because the thermal conductivity of a gas phase that occupies pore space is extremely small relative to that of the solid material. Furthermore, contributions from gaseous convection are generally insignificant.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求简要解释孔隙率如何降低陶瓷和聚合物材料的热导率，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释孔隙率如何降低陶瓷和聚合物材料的热导率，涉及对材料热传导机制的理解和概念关联，需要综合分析固体和气体相的热导率差异以及气体对流的影响。虽然不涉及复杂计算，但需要对多个概念进行关联和解释，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求解释孔隙率如何降低陶瓷和聚合物材料的热导率，涉及对气体相和固体材料热导率的比较，以及对气体对流贡献的理解。虽然不需要复杂的计算，但需要对相关概念有较深入的理解和综合分析能力。", "convertible": true, "correct_option": "Porosity decreases the thermal conductivity of ceramic and polymeric materials because the thermal conductivity of a gas phase that occupies pore space is extremely small relative to that of the solid material. Furthermore, contributions from gaseous convection are generally insignificant.", "choice_question": "Why does porosity decrease the thermal conductivity of ceramic and polymeric materials, rendering them more thermally insulative?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The gas phase in pores has much lower thermal conductivity than the solid matrix, and gaseous convection effects are negligible", "B": "Pores increase phonon scattering at interfaces, while gas molecules enhance radiative heat transfer", "C": "Porosity reduces density, which directly lowers thermal conductivity according to the Wiedemann-Franz law", "D": "Air-filled pores create thermal expansion mismatches that suppress lattice vibrations" }, "correct_answer": "A", "explanation": "Correct answer A identifies the primary mechanism (gas phase conductivity) and correctly dismisses convection. Option B combines a true phenomenon (phonon scattering) with a false one (radiative enhancement). Option C misapplies the Wiedemann-Franz law (which relates electrical and thermal conductivity in metals). Option D sounds plausible but incorrectly attributes the effect to thermal expansion rather than conductivity differences.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3928, "question": "The number of vacancies in some hypothetical metal increases by a factor of 5 when the temperature is increased from 1040 K to 1150 K. Calculate the energy (in kj/mol ) for vacancy formation assuming that the density of the metal remains the same over this temperature range.", "answer": "the energy for vacancy formation is 115 kj/mol.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解空缺形成能，答案是一个具体的数值结果（115 kj/mol），符合计算题的特征。 | 知识层次: 题目需要应用空位形成能的计算公式，涉及多步计算和温度对空位数的影响分析，需要理解并关联相关概念，但不需要复杂的推理或深度分析。 | 难度: 在选择题中属于中等偏上难度，需要理解空缺形成能的概念，并应用阿伦尼乌斯方程进行多步计算。题目涉及温度变化对空缺浓度的影响，要求考生能够综合运用热力学和材料科学知识进行推导和计算。虽然题目提供了正确选项，但解题过程需要一定的综合分析能力和数学运算技巧。", "convertible": true, "correct_option": "115 kj/mol", "choice_question": "The number of vacancies in some hypothetical metal increases by a factor of 5 when the temperature is increased from 1040 K to 1150 K. Calculate the energy (in kj/mol) for vacancy formation assuming that the density of the metal remains the same over this temperature range. The energy for vacancy formation is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "115 kJ/mol", "B": "92 kJ/mol", "C": "138 kJ/mol", "D": "76 kJ/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (115 kJ/mol) calculated using the Arrhenius relationship for vacancy formation energy. Option B (92 kJ/mol) is designed to exploit the common error of misapplying the temperature difference factor. Option C (138 kJ/mol) targets the tendency to overestimate activation energies in hypothetical systems. Option D (76 kJ/mol) is based on incorrect logarithmic transformation of the vacancy ratio, a frequent computational mistake in defect chemistry problems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4022, "question": "Complete the following statement regarding conditions that must be satisfied in order for a solid solution to exhibit extensive solubility. The solute and host species must feature [y] valence electron configuration. (y = a similar (or the same), a different)", "answer": "The solute and host species must feature a similar (or the same) valence electron configuration.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项中选择正确的答案填空，符合选择题的特征 | 知识层次: 题目考查对固溶体溶解度条件的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆固体溶解度条件中关于价电子构型的基本原理。正确选项明确且无需复杂分析，属于最简单的概念识别级别。", "convertible": true, "correct_option": "a similar (or the same)", "choice_question": "Complete the following statement regarding conditions that must be satisfied in order for a solid solution to exhibit extensive solubility. The solute and host species must feature [y] valence electron configuration.", "conversion_reason": "The original question is already in a multiple-choice format with implied options (a similar (or the same), a different). It can be directly converted to a standard single-choice question by explicitly listing these options and identifying the correct one.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "a similar (or the same)", "B": "a complementary", "C": "a different but isoelectronic", "D": "a significantly higher" }, "correct_answer": "A", "explanation": "The correct answer is A because extensive solid solubility requires similar valence electron configurations to maintain similar bonding characteristics. Option B exploits the cognitive bias of 'complementary' being attractive in other contexts. Option C uses the isoelectronic concept which is relevant but insufficient for solubility. Option D targets the common misconception that higher valence electrons always improve solubility.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 230, "question": "When the clay mineral kaolinite (Al2O3•2SiO2•2H2O) is heated to 600°C, it decomposes into water vapor and Al2O3•2SiO2. What happens when it is further heated to 1595°C?", "answer": "When heated to 1595°C, A3S2 is formed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释当高岭石加热到1595°C时会发生什么变化，答案需要文字描述反应产物，属于简答题类型。 | 知识层次: 题目需要理解高岭石在不同温度下的分解过程，并关联到具体的化学反应和产物形成。虽然涉及记忆性知识（如化学式），但更侧重于在不同温度条件下物质变化的分析和应用，需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及粘土矿物高岭石在不同温度下的分解过程，要求考生掌握高岭石的热分解反应及其产物。虽然题目给出了部分反应信息，但需要考生综合理解并推断在更高温度下的反应产物。这需要一定的材料科学知识背景和逻辑推理能力，但题目提供了部分线索，降低了难度。", "convertible": true, "correct_option": "A3S2 is formed", "choice_question": "When the clay mineral kaolinite (Al2O3•2SiO2•2H2O) is heated to 600°C, it decomposes into water vapor and Al2O3•2SiO2. What happens when it is further heated to 1595°C?", "conversion_reason": "The answer is a standard term or concept (A3S2 is formed), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A3S2 is formed", "B": "Mullite (3Al2O3•2SiO2) crystallizes", "C": "Complete decomposition into Al2O3 and SiO2 occurs", "D": "Metastable γ-Al2O3 phase appears" }, "correct_answer": "A", "explanation": "The correct answer is A because at 1595°C, kaolinite undergoes a high-temperature transformation to form aluminum silicate (A3S2). Option B exploits the common knowledge that mullite forms from kaolinite, but ignores the specific temperature condition. Option C creates a false intuition about complete decomposition being the logical endpoint. Option D leverages the well-known γ-Al2O3 phase transition but applies it at the wrong temperature range.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1487, "question": "Explain the role of Suzuki atmosphere in strengthening metals", "answer": "Suzuki atmosphere: In FCC crystals (such as stainless steel), alloying elements like Ni and α preferentially distribute in stacking fault regions, reducing the stacking fault energy and expanding the extended dislocation zone. To move these extended dislocations, additional stress is required, thereby increasing the material's strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Suzuki atmosphere在强化金属中的作用，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释Suzuki atmosphere在金属强化中的作用机制，涉及FCC晶体结构、合金元素分布、堆垛层错能变化以及位错运动等概念的关联和综合分析，需要深入理解材料微观结构与性能之间的关系，并进行推理分析。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求深入理解Suzuki atmosphere的复杂机理，包括FCC晶体结构、合金元素分布、堆垛层错能变化以及位错运动等专业概念的综合运用。正确选项不仅需要识别这些概念，还要能够解释它们之间的相互作用如何导致材料强化。这种题目在选择题中属于需要全面分析复杂现象的题型，对学生的知识深度和综合分析能力要求极高。", "convertible": true, "correct_option": "Suzuki atmosphere: In FCC crystals (such as stainless steel), alloying elements like Ni and α preferentially distribute in stacking fault regions, reducing the stacking fault energy and expanding the extended dislocation zone. To move these extended dislocations, additional stress is required, thereby increasing the material's strength.", "choice_question": "Which of the following best describes the role of Suzuki atmosphere in strengthening metals?", "conversion_reason": "The answer is a standard explanation of a concept, which can be converted into a multiple-choice question format by presenting it as the correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Suzuki atmosphere reduces stacking fault energy in FCC crystals by segregating alloying elements to stacking fault regions, requiring higher stress for dislocation motion", "B": "Suzuki atmosphere increases dislocation density by introducing interstitial impurities that pin dislocations through Cottrell atmospheres", "C": "Suzuki atmosphere enhances grain boundary strengthening by preferential segregation of solute atoms to grain boundaries", "D": "Suzuki atmosphere creates short-range ordering that increases the Peierls stress for dislocation movement in BCC metals" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes the Suzuki mechanism in FCC crystals where solute segregation reduces stacking fault energy and expands extended dislocations. Option B incorrectly conflates Suzuki with Cottrell atmospheres. Option C misattributes grain boundary strengthening. Option D wrongly applies the concept to BCC metals and introduces Peierls stress confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3641, "question": "Calculate the planar packing fraction (ppf) on the (110) plane for CaF2 (with the fluorite structure).", "answer": "0.699", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算CaF2在(110)面上的平面堆积分数(ppf)，需要使用数值计算和公式应用，最终答案是一个具体的数值(0.699)。 | 知识层次: 题目需要计算平面堆积分数（ppf），这涉及到理解晶体结构（氟化钙的萤石结构）和特定晶面（110）的原子排列。计算过程需要应用几何关系和公式，涉及多步计算和概念关联，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解氟化钙的萤石结构、(110)晶面的原子排列方式，并进行多步计算（包括确定晶面原子数、计算有效原子面积和晶面面积等）。虽然题目提供了正确选项，但解题过程涉及概念关联和综合分析，比单纯记忆或简单计算的选择题更复杂。", "convertible": true, "correct_option": "0.699", "choice_question": "What is the planar packing fraction (ppf) on the (110) plane for CaF2 (with the fluorite structure)?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.699", "B": "0.785", "C": "0.524", "D": "0.906" }, "correct_answer": "A", "explanation": "The correct answer is A (0.699) because the (110) plane in fluorite structure contains both Ca and F ions arranged in a specific pattern that yields this packing fraction. Option B (0.785) is a common trap as it's the ppf for simple cubic (100) planes, exploiting confusion between different crystal structures. Option C (0.524) mimics the ppf for FCC (111) planes, targeting incorrect structural analogy. Option D (0.906) represents the theoretical maximum for hexagonal close packing, designed to catch those who overestimate packing efficiency without considering the fluorite structure's unique ionic arrangement.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1984, "question": "When the radii of silicon and oxygen in quartz (SiO2) are 0.038 nm and 0.114 nm respectively, what is the packing density (assuming the atoms are spherical)?", "answer": "0.33", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解石英的堆积密度，答案是一个具体的数值（0.33），解答过程需要运用材料科学中的相关公式和计算步骤。 | 知识层次: 题目需要进行基本的数值计算和公式应用，涉及原子半径和堆积密度的简单计算，属于直接套用公式的范畴，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算石英（SiO2）的堆积密度，只需要应用堆积密度的基本公式（原子体积总和除以晶胞体积），并代入给定的硅和氧的半径值进行简单计算即可。无需组合多个公式或进行复杂的推导分析，因此属于最基础的难度等级。", "convertible": true, "correct_option": "0.33", "choice_question": "When the radii of silicon and oxygen in quartz (SiO2) are 0.038 nm and 0.114 nm respectively, what is the packing density (assuming the atoms are spherical)?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.33", "B": "0.42", "C": "0.28", "D": "0.37" }, "correct_answer": "A", "explanation": "The correct packing density is calculated by considering the volume occupied by Si and O atoms in the quartz unit cell divided by the total unit cell volume. Option B (0.42) exploits the common misconception of using simple cubic packing density. Option C (0.28) is derived from incorrectly assuming only oxygen contributes to packing. Option D (0.37) is a trap for those who miscalculate the coordination number effect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1823, "question": "A crystal with space group Fm3m has a (5)_ structure.", "answer": "(5) face-centered cubic structure", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的晶体结构名称，需要根据空间群Fm3m的知识进行文字回答，而不是从多个选项中选择或进行数值计算。 | 知识层次: 题目考查对晶体结构空间群Fm3m对应的具体结构类型的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，此题属于基本定义简答难度。题目仅要求识别空间群Fm3m对应的晶体结构类型（面心立方），属于晶体学中最基础的空间群与结构对应关系记忆，无需解释或推导过程。选择题的正确选项直接提供了答案，考察的是对单一知识点的机械记忆能力，在选择题难度谱系中属于最低层级。", "convertible": true, "correct_option": "face-centered cubic structure", "choice_question": "A crystal with space group Fm3m has a:", "conversion_reason": "简答题的答案是标准术语，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "face-centered cubic structure", "B": "body-centered cubic structure", "C": "hexagonal close-packed structure", "D": "simple cubic structure with octahedral voids" }, "correct_answer": "A", "explanation": "The space group Fm3m corresponds to a face-centered cubic (FCC) structure, which is the correct answer (A). Option B (BCC) is a common confusion due to the cubic symmetry but incorrect space group. Option C (HCP) exploits the tendency to associate close-packing with FCC, while HCP has a different space group. Option D creates a sophisticated trap by combining correct cubic symmetry with an incorrect void description, targeting systems that overanalyze the 'm3m' notation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 282, "question": "According to the phase transition mechanism, what types can it be divided into?", "answer": "According to the phase transition mechanism, it can be divided into diffusion-type phase transition, non-diffusion-type phase transition, and semi-diffusion-type phase transition. Phase transitions that rely on long-distance diffusion of atoms or ions are called diffusion-type phase transitions. Non-diffusion-type phase transitions refer to the movement of atoms or ions, but the relative displacement does not exceed the atomic spacing.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求根据相变机制进行分类，并需要文字解释和论述不同类型的相变机制。答案提供了详细的分类和定义，符合简答题的特征。 | 知识层次: 题目考查的是对相变机制分类的基本概念记忆和理解，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及相变机制的分类，但正确选项已经提供了明确的定义和分类，考生只需理解并记忆这些基本概念即可。不需要进行复杂的分析或推理，但需要掌握相关术语和分类标准。", "convertible": true, "correct_option": "diffusion-type phase transition, non-diffusion-type phase transition, and semi-diffusion-type phase transition", "choice_question": "According to the phase transition mechanism, what types can it be divided into?", "conversion_reason": "The answer is a standard set of terms that can be presented as options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "diffusion-type phase transition, non-diffusion-type phase transition, and semi-diffusion-type phase transition", "B": "first-order phase transition and second-order phase transition", "C": "nucleation-type phase transition and spinodal decomposition", "D": "thermodynamic phase transition and kinetic phase transition" }, "correct_answer": "A", "explanation": "The correct classification is based on atomic movement mechanisms during phase transition. Option B is a thermodynamic classification that often confuses students. Option C describes specific mechanisms rather than fundamental types. Option D mixes classification criteria by combining thermodynamic and kinetic aspects, creating a logical inconsistency.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 425, "question": "6. Common methods for strengthening metal materials include: (15)", "answer": "Dispersion strengthening", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举金属材料的强化方法，需要文字解释和论述，而不是从选项中选择或判断对错。答案\"Dispersion strengthening\"是一个简短的文字回答，符合简答题的特征。 | 知识层次: 题目考查金属材料强化方法的基本概念记忆，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅考察对金属材料强化方法的基础概念记忆，属于最基础的定义性知识。学生只需识别\"弥散强化\"这一术语即可作答，无需进行概念解释或复杂分析，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Dispersion strengthening", "choice_question": "Which of the following is a common method for strengthening metal materials?", "conversion_reason": "The answer is a standard term (Dispersion strengthening) which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit the multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dispersion strengthening", "B": "Increasing elastic modulus", "C": "Reducing dislocation density", "D": "Enhancing surface reflectivity" }, "correct_answer": "A", "explanation": "Dispersion strengthening is correct as it involves adding fine particles to impede dislocation motion. Option B exploits the common confusion between elastic modulus (intrinsic property) and strength (can be modified). Option C is a reverse intuition trap since reducing dislocations actually weakens metals. Option D uses an irrelevant surface property to mislead those who confuse optical and mechanical properties.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3586, "question": "Calculate the atomic radius in cm for an FCC metal with a0=4.0862 A and one atom per lattice point.", "answer": "1.4447 x 10^-8 cm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算原子半径），并给出了具体的公式应用（FCC结构中的原子半径与晶格参数的关系），最终答案是一个具体的数值结果。 | 知识层次: 题目要求应用FCC晶体结构的几何关系公式进行单步计算，属于基本公式的直接套用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目明确给出了FCC金属的晶格常数a0=4.0862 Å，并要求计算原子半径。解题仅需应用FCC结构中原子半径与晶格常数的关系公式（r = a0√2 / 4），并进行简单的单位换算（Å到cm）。无需额外的概念理解或复杂步骤，属于最基础的直接套用公式类型。", "convertible": true, "correct_option": "1.4447 x 10^-8 cm", "choice_question": "What is the atomic radius in cm for an FCC metal with a0=4.0862 A and one atom per lattice point?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.4447 x 10^-8 cm", "B": "2.8894 x 10^-8 cm", "C": "1.0243 x 10^-8 cm", "D": "2.0486 x 10^-8 cm" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the FCC relationship r = a0√2/4. Option B incorrectly uses the diameter instead of radius. Option C is a BCC radius calculation (r = a0√3/4), exploiting crystal structure confusion. Option D is the FCC nearest neighbor distance (a0√2/2), designed to trap those who confuse atomic radius with interatomic distance.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2082, "question": "Should high carbon steel or low carbon steel be used to manufacture automobile fenders?", "answer": "High carbon steel. Because high carbon steel has high strength and can withstand greater impact force without deformation. In contrast, low carbon steel is softer and more prone to deformation under force.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述为什么选择高碳钢而不是低碳钢来制造汽车挡泥板，答案提供了详细的文字解释和比较，符合简答题的特征。 | 知识层次: 题目要求学生理解高碳钢和低碳钢的性能差异，并应用这些知识来选择适合制造汽车挡泥板的材料。这涉及到对材料性能的综合分析和实际应用，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解高碳钢和低碳钢的基本特性（如强度和抗变形能力），并能将这些概念与汽车挡泥板的应用场景进行关联分析。题目要求考生在给定选项中综合比较两种材料的性能差异，并选择最适合应用场景的选项，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "High carbon steel", "choice_question": "Which type of steel should be used to manufacture automobile fenders?", "conversion_reason": "The original question is a short answer question that asks for a specific choice between two options (high carbon steel or low carbon steel). The answer provided is a clear and definitive choice (high carbon steel) with supporting reasoning. This makes it suitable for conversion into a multiple-choice question format where the options would be the two types of steel.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High carbon steel for superior dent resistance", "B": "Low carbon steel for better formability during stamping", "C": "Medium carbon steel to balance strength and ductility", "D": "Dual-phase steel for optimal crash energy absorption" }, "correct_answer": "B", "explanation": "Low carbon steel is correct due to its excellent formability for complex fender shapes and adequate strength for dent resistance. Option A exploits the intuitive but incorrect assumption that higher carbon means better performance. Option C creates a false compromise position. Option D introduces a technically advanced but unnecessarily expensive material for this application.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2916, "question": "During solid-state phase transformation, assuming the volume free energy change per atom is ΔGB=200ΔT/Tc, in units of J/cm³, the critical transformation temperature Tc=1000K, strain energy ε=4J/cm³, coherent interface energy σ_coherent=4.0×10⁻⁶ J/cm², and incoherent interface energy σ_incoherent=4.0×10⁻⁵ J/cm², calculate the ratio of critical nucleation work ΔG_coherent* to ΔG_incoherent* when ΔT=50°C.", "answer": "The nucleation work for a spherical nucleus is ΔG_coherent*=16πσ³/3(ΔGB−ε)², and if the interface is incoherent, the strain energy can be neglected, with the nucleation work being ΔG_incoherent*=16πσ³/3ΔGB². The ratio ΔG_coherent*/ΔG_incoherent*=ΔGB²σ_coherent³/(ΔGB−ε)²σ_incoherent³ =[(200×50/1000)²×(4.0×10⁻⁶)³]/[(200×50/1000−4)²×(4.0×10⁻⁵)³]=2.777×10⁻³.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及多个物理量的代入和运算，最终需要计算出一个具体的数值结果。答案中展示了详细的推导过程和最终计算结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要理解相变过程中的能量变化、临界成核功的计算公式，并能够正确应用这些公式进行数值计算。虽然题目提供了具体的公式，但需要综合运用体积自由能变化、应变能和界面能等概念，并进行适当的代数运算来求解比例。这超出了简单应用的范畴，但尚未达到需要复杂分析或高级综合的层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及固体相变中的临界形核功计算，需要掌握体积自由能变化、应变能、共格和非共格界面能等概念，并进行多步计算。虽然题目提供了公式和计算步骤，但仍需要综合应用这些知识来求解比例，属于中等应用层次。", "convertible": true, "correct_option": "2.777×10⁻³", "choice_question": "During solid-state phase transformation, assuming the volume free energy change per atom is ΔGB=200ΔT/Tc, in units of J/cm³, the critical transformation temperature Tc=1000K, strain energy ε=4J/cm³, coherent interface energy σ_coherent=4.0×10⁻⁶ J/cm², and incoherent interface energy σ_incoherent=4.0×10⁻⁵ J/cm², calculate the ratio of critical nucleation work ΔG_coherent* to ΔG_incoherent* when ΔT=50°C. The ratio is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.777×10⁻³", "B": "1.389×10⁻²", "C": "5.554×10⁻³", "D": "1.111×10⁻²" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算临界形核功比值得出。干扰项B错误地将应变能ε纳入分母计算，利用了材料科学中能量项叠加的常见误区。干扰项C是正确答案的2倍，利用了计算过程中可能遗漏1/2系数的直觉陷阱。干扰项D将相干与非相干界面能直接相除(σ_coherent/σ_incoherent)，这是表面合理但实际错误的简化计算方式。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1675, "question": "Given the ionic radius of O2- is 0.14nm and that of Fe3+ is 0.069nm, calculate their radius ratio and predict what type of crystal structure can be formed.", "answer": "Fe2O3, R+/R-=0.069/0.140=0.492, which also falls within the range of 0.414～0.732, has 6-coordination, A2X3 structure, trigonal crystal system.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算半径比）并应用晶体结构预测的知识（根据半径比范围判断配位数和晶体结构类型），答案给出了具体的计算过程和结构预测结果。 | 知识层次: 题目需要进行多步计算（半径比计算、配位数判断），并关联晶体结构类型的综合分析，涉及离子半径比与晶体结构的关系这一中等复杂度的知识点。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求计算离子半径比，并根据计算结果预测晶体结构类型。这涉及到多步骤的计算过程（半径比计算）和概念关联（半径比与配位数、晶体结构的关系）。虽然题目提供了具体数值，但仍需要综合分析才能得出正确结论。", "convertible": true, "correct_option": "A2X3 structure, trigonal crystal system", "choice_question": "Given the ionic radius of O2- is 0.14nm and that of Fe3+ is 0.069nm, their radius ratio is 0.492. What type of crystal structure can be formed?", "conversion_reason": "The answer is a specific crystal structure type, which can be presented as a clear option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A2X3 structure, trigonal crystal system", "B": "AX structure, cubic crystal system", "C": "AX2 structure, hexagonal crystal system", "D": "A2X structure, tetragonal crystal system" }, "correct_answer": "A", "explanation": "The correct answer is A because the radius ratio of 0.492 falls within the range for octahedral coordination (0.414-0.732), which is typical for A2X3 structures like Fe2O3 in the trigonal system. Option B is a cognitive bias trap, as cubic structures are more common for simpler AX compounds. Option C exploits the hexagonal intuition from similar radius ratios in other systems. Option D is a multi-level trap combining incorrect stoichiometry with a plausible crystal system.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1276, "question": "During the crystallization process of solid solution alloys, the laws of nucleation and grain growth are followed, but unlike pure metals, what additional fluctuation is required during nucleation?", "answer": "composition", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释在固溶体合金结晶过程中除了遵循形核和晶粒生长规律外，还需要什么额外的波动，答案需要文字解释和论述，而不是从选项中选择或简单的对错判断。 | 知识层次: 题目考查对固溶体合金结晶过程中成核和晶粒生长规律的理解，需要将纯金属的结晶过程与固溶体合金进行比较，并识别出额外的成分波动要求。这涉及多步概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题中属于中等难度，需要理解固溶体合金结晶过程中的成核规律，并区分其与纯金属成核的差异。题目要求考生掌握成分波动这一关键概念，并进行综合分析判断。", "convertible": true, "correct_option": "composition", "choice_question": "During the crystallization process of solid solution alloys, the laws of nucleation and grain growth are followed, but unlike pure metals, what additional fluctuation is required during nucleation?", "conversion_reason": "The answer is a standard term (composition), which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "temperature gradient", "B": "composition", "C": "lattice strain", "D": "dislocation density" }, "correct_answer": "B", "explanation": "The correct answer is B (composition) because solid solution alloys require compositional fluctuations during nucleation to achieve the necessary chemical inhomogeneity for phase separation. Option A (temperature gradient) is a common nucleation factor but not specific to alloys. Option C (lattice strain) exploits the intuition that strain affects nucleation but is secondary to composition. Option D (dislocation density) is a red herring that misdirects toward crystal defects rather than chemical fluctuations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3388, "question": "The bolts on the gear hobbing machine should have been made of 45 steel, but T12 steel was mistakenly used. The high-temperature tempering process for 45 steel was still applied. What microstructure will be obtained in this case? What will be the performance?", "answer": "High-temperature tempering: The microstructure consists of coarse tempered sorbite and retained austenite; Performance: Poor toughness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释材料在特定热处理条件下的微观结构和性能，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目需要理解不同钢材（45钢和T12钢）在高温回火后的显微组织和性能变化，涉及材料选择错误导致的显微组织差异及其对性能的影响。这需要多步分析和概念关联，包括对钢材成分、热处理工艺和显微组织之间关系的理解，以及对性能影响的综合分析。 | 难度: 在选择题中属于较高难度，需要综合理解材料科学中的多个概念（如钢种特性、热处理工艺、显微组织与性能关系），并分析错误材料选择与工艺应用导致的非预期结果。题目要求考生不仅掌握45钢和T12钢的本质区别（共析钢与过共析钢），还需预判错误热处理工艺（高温回火）对T12钢显微组织（粗大回火索氏体+残余奥氏体）和力学性能（韧性恶化）的影响，涉及多步骤逻辑推理和跨知识点关联分析。", "convertible": true, "correct_option": "High-temperature tempering: The microstructure consists of coarse tempered sorbite and retained austenite; Performance: Poor toughness.", "choice_question": "The bolts on the gear hobbing machine should have been made of 45 steel, but T12 steel was mistakenly used. The high-temperature tempering process for 45 steel was still applied. What microstructure and performance will be obtained in this case?", "conversion_reason": "The answer is a standard description of the microstructure and performance, which can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fine tempered martensite with good toughness and ductility", "B": "Coarse tempered sorbite with retained austenite and poor toughness", "C": "Spheroidized cementite in ferrite matrix with excellent machinability", "D": "Bainitic structure with balanced strength and toughness" }, "correct_answer": "B", "explanation": "The correct answer is B because T12 steel is a hypereutectoid steel with high carbon content. High-temperature tempering will result in coarse tempered sorbite and retained austenite, leading to poor toughness. Option A is wrong because it describes the typical microstructure of properly tempered medium-carbon steel (like 45 steel). Option C is a trap based on the spheroidizing annealing process often used for tool steels, but this is not the result of high-temperature tempering. Option D incorrectly suggests bainite formation, which requires specific cooling rates not achieved in tempering.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4222, "question": "Convert the (101) plane into the four-index Miller-Bravais scheme for hexagonal unit cells.", "answer": "the (101) plane in the four-index miller-bravais scheme is (10 -1 1).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求将(101)平面转换为六方晶系的四指数Miller-Bravais表示法，需要文字解释和论述转换过程，答案是一个具体的平面指数表示，属于简答题类型。 | 知识层次: 题目需要将立方晶系的Miller指数转换为六方晶系的Miller-Bravais指数，这涉及多步计算和概念关联，需要理解两种晶系指数的转换规则并进行适当的数学运算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。该题目要求将(101)平面转换为六方晶系的四指数Miller-Bravais方案，涉及对晶面指数的理解和计算。虽然题目给出了正确选项，但学生需要掌握六方晶系和三指数到四指数的转换规则，并进行适当的计算。这需要一定的概念关联和综合分析能力，但相比更复杂的题目，步骤相对明确，因此在选择题型中属于中等难度。", "convertible": true, "correct_option": "(10 -1 1)", "choice_question": "Convert the (101) plane into the four-index Miller-Bravais scheme for hexagonal unit cells. Which of the following is the correct representation?", "conversion_reason": "The answer is a standard term in crystallography, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(10 -1 1)", "B": "(1 0 -1 1)", "C": "(1 0 1 0)", "D": "(1 0 -1 0)" }, "correct_answer": "A", "explanation": "The correct conversion of (101) to Miller-Bravais indices is (10 -1 1). Option B is a common error where the redundant index is incorrectly placed. Option C exploits the misconception that the third index should mirror the first in hexagonal systems. Option D is a partial transformation that fails to account for the four-index symmetry requirement.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 608, "question": "The crystal structure of austenite is", "answer": "FCC", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答奥氏体的晶体结构，答案是一个简短的术语（FCC），不需要从多个选项中选择，也不涉及判断对错或数值计算。 | 知识层次: 题目考查对奥氏体晶体结构这一基础概念的记忆，属于材料科学中最基本的相结构知识，不需要复杂的分析或应用过程。 | 难度: 在选择题型中，该题目仅考察对奥氏体晶体结构的基础定义记忆（FCC），属于最基础的概念性知识，无需解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "FCC", "choice_question": "The crystal structure of austenite is:", "conversion_reason": "简答题的答案是标准术语，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "FCC", "B": "BCC with tetragonal distortion", "C": "HCP with stacking faults", "D": "BCC with carbon interstitial sites" }, "correct_answer": "A", "explanation": "Austenite is the face-centered cubic (FCC) phase of iron or steel. Option B exploits the common confusion with martensite which is BCC with tetragonal distortion. Option C targets the misconception that HCP structures are common in steel phases. Option D leverages the intuitive but incorrect association between carbon content and BCC structure in ferrite. Advanced AI might overthink the carbon influence (D) or phase transformation nuances (B).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4332, "question": "Consider 2.5 kg of austenite containing 0.65 wt % C, cooled to below 727 C (1341 F). What is the proeutectoid phase?", "answer": "ferrite is the proeutectoid phase.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求通过文字解释和论述来确定proeutectoid phase，而不是从多个选项中选择、判断对错或进行数值计算。答案“ferrite is the proeutectoid phase”是一个简短的文字回答，符合简答题的特征。 | 知识层次: 题目需要应用铁碳相图的基本知识来确定先共析相，涉及简单的相图分析和成分判断，属于直接套用基础知识的简单应用。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需基本公式应用和简单计算，直接套用知识点即可得出正确答案。题目要求判断亚共析相，只需根据给定的碳含量（0.65 wt% C）和冷却温度（低于727°C）直接应用铁碳相图的基本知识即可确定先共析相为铁素体（ferrite），无需复杂分析或多步骤推理。", "convertible": true, "correct_option": "ferrite", "choice_question": "Consider 2.5 kg of austenite containing 0.65 wt % C, cooled to below 727 C (1341 F). What is the proeutectoid phase?", "conversion_reason": "The answer is a standard term (ferrite), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ferrite", "B": "cementite", "C": "pearlite", "D": "ledeburite" }, "correct_answer": "A", "explanation": "The correct answer is ferrite because at 0.65 wt% C (hypoeutectoid composition), the proeutectoid phase forming upon cooling below 727°C is ferrite. Option B (cementite) is incorrect but tempting as it's the proeutectoid phase for hypereutectoid steels. Option C (pearlite) is incorrect but plausible as it forms below 727°C, though it's not the proeutectoid phase. Option D (ledeburite) is incorrect but uses a less common term that might confuse those unfamiliar with cast iron microstructures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2867, "question": "When moving dislocations are pinned, their average spacing is $\\scriptstyle{\\ell=\\rho^{-{\\frac{1}{2}}}(\\rho}$ is the dislocation density). It is given that a $\\mathtt{Cu}$ single crystal has been strain-hardened to the extent that the resolved shear stress acting on the crystal is 14MPa. Given $G=40\\mathrm{GPa},b=0,256$ $\\scriptstyle{\\mathtt{n m}}$, calculate the dislocation density of the $\\mathtt{Cu}$ single crystal.", "answer": "After moving dislocations are pinned, a dislocation segment of length $\\boldsymbol{\\ell}$ can act as a dislocation source, and the resolved shear stress required to activate this dislocation source is $$\\tau_{\\mathrm{c}}=\\frac{G b}{l},$$$$14\\times10^{6}=\\frac{40\\times10^{9}\\times0.256\\times10^{-9}}{\\rho^{-\\frac{1}{2}}},$$$$\\rho{=1.869\\times10^{12}(\\mathrm{m}^{-2})}$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的公式和数值进行具体的计算，最终得出一个数值结果（dislocation density）。答案中展示了详细的公式推导和计算过程，符合计算题的特征。 | 知识层次: 题目需要应用位错钉扎的基本原理和公式，进行多步计算和单位转换，涉及位错密度与剪切应力的关系，需要一定的综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及多步计算和概念关联，包括理解位错钉扎、位错密度与应力之间的关系，以及应用相关公式进行综合计算。虽然题目提供了必要的公式和数据，但解题过程需要一定的综合分析能力和数学运算技巧。", "convertible": true, "correct_option": "1.869×10¹² m⁻²", "choice_question": "A strain-hardened Cu single crystal has a resolved shear stress of 14MPa. Given the shear modulus G=40GPa and Burgers vector b=0.256 nm, calculate the dislocation density of the Cu single crystal.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option among multiple choices in a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.869×10¹² m⁻²", "B": "3.738×10¹² m⁻²", "C": "9.345×10¹¹ m⁻²", "D": "2.803×10¹² m⁻²" }, "correct_answer": "A", "explanation": "The correct answer is derived from the Taylor relation τ=αGb√ρ, where α is a constant typically taken as 0.5 for FCC metals like Cu. Solving for ρ gives ρ=(τ/αGb)². Option B doubles the correct value by incorrectly using α=1. Option C is half the correct value due to a square root error. Option D results from misapplying the modulus by using E instead of G in calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 426, "question": "5. The two basic characteristics of martensitic transformation are (11)", "answer": "Diffusionless transformation", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答马氏体相变的基本特征，需要简要的文字解释和论述，而不是从选项中选择或判断对错。答案\"Diffusionless transformation\"是一个简短的描述性回答。 | 知识层次: 题目考查马氏体相变的基本特征，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆马氏体相变的基本特征之一（无扩散转变），属于基础概念记忆层次。题目仅涉及单一知识点的直接回忆，无需解释或复杂分析，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "Diffusionless transformation", "choice_question": "Which of the following is one of the two basic characteristics of martensitic transformation?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diffusionless transformation", "B": "Isothermal phase transition", "C": "Continuous lattice distortion", "D": "Equilibrium thermodynamic process" }, "correct_answer": "A", "explanation": "The correct answer is A because martensitic transformation is characterized by a diffusionless, shear-type mechanism. Option B is incorrect as it's an athermal transformation, not isothermal. Option C is a cognitive bias trap - while there is lattice distortion, it's discontinuous (habit plane formation). Option D exploits thermodynamic intuition by suggesting equilibrium conditions, whereas martensite is metastable.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1315, "question": "What mainly occurs during the high-temperature recovery of cold-worked metals?", "answer": "Polygonization", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释冷加工金属在高温恢复过程中主要发生的现象，答案需要提供文字解释而非选择或判断 | 知识层次: 题目考查的是冷加工金属高温回复过程中主要发生的现象（多边形化），属于基础概念的记忆和理解范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然考查的是基础概念记忆，但\"polygonization\"是金属高温回复过程中的一个特定术语，需要学生不仅记住定义，还要理解其在冷加工金属恢复过程中的具体应用场景。这比单纯记忆基本定义(等级1)要求更高，但不需要进行复杂概念体系的分析比较(等级3)。", "convertible": true, "correct_option": "Polygonization", "choice_question": "What mainly occurs during the high-temperature recovery of cold-worked metals?", "conversion_reason": "The answer is a standard term (Polygonization), which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Polygonization", "B": "Recrystallization", "C": "Dislocation annihilation", "D": "Grain boundary migration" }, "correct_answer": "A", "explanation": "The correct answer is A because polygonization specifically describes the rearrangement of dislocations into low-angle grain boundaries during high-temperature recovery. Option B is incorrect because recrystallization is a separate process that occurs at higher temperatures. Option C is a plausible but incomplete answer as dislocation annihilation occurs but isn't the defining characteristic. Option D is incorrect because grain boundary migration is more characteristic of recrystallization than recovery.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3509, "question": "Compare the anti-friction properties of HT150 and annealed 20 steel", "answer": "HT150 has better anti-friction properties than 20 steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的抗摩擦性能，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求比较两种材料的抗摩擦性能，需要理解材料的基本性质（如HT150的铸铁特性和20钢的退火状态特性），并分析这些性质如何影响抗摩擦性能。这涉及多步分析和概念关联，但不需要复杂的机理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解HT150和20钢的材料特性，并进行抗摩擦性能的比较分析。题目要求考生综合运用材料科学知识，对两种材料的性能进行对比，涉及多步计算和概念关联。", "convertible": true, "correct_option": "HT150 has better anti-friction properties than 20 steel.", "choice_question": "Compare the anti-friction properties of HT150 and annealed 20 steel:", "conversion_reason": "The answer is a clear comparison statement that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "HT150 has better anti-friction properties due to its higher graphite content", "B": "20 steel shows superior anti-friction performance after annealing due to carbide precipitation", "C": "Both materials exhibit similar anti-friction properties as they have comparable hardness", "D": "HT150 performs worse due to its lower yield strength compared to 20 steel" }, "correct_answer": "A", "explanation": "The correct answer is A because HT150, as a cast iron, contains graphite flakes that provide self-lubricating properties. Option B is a cognitive bias trap - while carbide precipitation occurs, it doesn't improve anti-friction. Option C exploits hardness misconception - hardness alone doesn't determine friction. Option D uses irrelevant mechanical property to mislead about tribological performance.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1457, "question": "For metals that have undergone pre-cold plastic deformation, (44) annealing should be performed before further cold plastic deformation to improve their (45)", "answer": "recrystallization; plasticity and toughness", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写两个空白处（44和45），需要根据材料科学知识提供具体的术语（recrystallization; plasticity and toughness），属于简答题类型，需要文字解释和论述。 | 知识层次: 题目考查对金属冷塑性变形后热处理的基本概念记忆，即再结晶退火的作用（改善塑性和韧性），属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅考察对金属热处理过程中\"再结晶退火\"这一基础概念的简单记忆，以及对其作用（提高塑性和韧性）的基本认知。不需要进行概念解释或复杂分析，属于最基础的知识点考察。", "convertible": true, "correct_option": "recrystallization", "choice_question": "For metals that have undergone pre-cold plastic deformation, which type of annealing should be performed before further cold plastic deformation to improve their plasticity and toughness?", "conversion_reason": "The answer is a standard term (recrystallization) which can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit the multiple-choice format by asking for the type of annealing.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization annealing", "B": "Stress relief annealing", "C": "Homogenization annealing", "D": "Spheroidization annealing" }, "correct_answer": "A", "explanation": "Recrystallization annealing is the correct choice because it eliminates the strain hardening effects from pre-cold deformation by forming new strain-free grains, thus restoring plasticity and toughness. Stress relief annealing (B) is a distractor that appeals to intuitive association with 'relieving' deformation effects but only reduces residual stresses without significantly improving plasticity. Homogenization annealing (C) exploits the common misconception about uniform microstructure but is actually for eliminating chemical segregation in castings. Spheroidization annealing (D) is a specialized process for high-carbon steels that creates a misleading analogy with 'softening' effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2620, "question": "The atomic number of platinum is 78, it has only 9 electrons in the 5d subshell and no electrons in the 5f subshell. How many electrons are there in the 6s subshell of Pt?", "answer": "$\\\\mathrm{ls^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10}4s^{2}4p^{6}4d^{10}4f^{14}5s^{2}5p^{6}5d^{9}6s^{1}};$ $2+8+18+32+17=77;\\\\quad78-77=1$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过计算确定铂原子6s子壳层中的电子数，答案涉及电子排布和数值计算，符合计算题的特征。 | 知识层次: 题目需要进行多步计算和概念关联，包括电子排布的规则理解和应用，以及简单的减法运算。虽然不涉及复杂的推理分析，但需要综合运用电子排布的知识和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要掌握电子排布规则并进行多步计算。题目要求考生理解铂原子（原子序数78）的电子排布，特别是5d和6s轨道的填充情况。解题过程涉及核对电子总数（78个电子）与已给出电子排布的总和（77个电子）之间的差异，从而得出6s轨道有1个电子的结论。虽然题目提供了部分电子排布信息，但仍需要考生具备综合分析能力和计算技巧，属于综合性计算问题。", "convertible": true, "correct_option": "1", "choice_question": "The atomic number of platinum is 78, it has only 9 electrons in the 5d subshell and no electrons in the 5f subshell. How many electrons are there in the 6s subshell of Pt?", "conversion_reason": "The answer to the calculation is a specific numerical value (1), which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项B", "B": "选项C", "C": "选项D", "D": "1" }, "correct_answer": "D", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 2979, "question": "In the ionic compound $\\\\mathbf{MgO}$, the cation most likely to replace $\\\\mathbf{Mg}^{2+}$ in the compound (given the radii (nm) of each cation: (${\\\\bf Mg}^{2+}$) 0.066, ($\\\\mathbb{C}a^{2+}$) 0.099, ($\\\\mathrm{Li^{+}}$) 0.066, ($\\\\mathbf{Fe}^{\\\\mathbf{2+}}$) 0.074) is", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的多个选项中选择最可能替换Mg2+的阳离子，答案以选项形式给出（C），符合选择题的特征。 | 知识层次: 题目考查离子半径数据的直接应用，需要根据给定的离子半径数据选择最可能替换Mg²⁰的阳离子。虽然涉及离子半径的概念，但主要是简单的数据比较和选择，不需要复杂的分析或推理。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接比较给定离子半径数据并选择最接近Mg²⁰半径的选项（Ca²⁺）。无需复杂计算或公式变形，属于基础概念的直接应用。", "convertible": true, "correct_option": "C", "choice_question": "In the ionic compound $\\mathbf{MgO}$, the cation most likely to replace $\\mathbf{Mg}^{2+}$ in the compound (given the radii (nm) of each cation: (${\\bf Mg}^{2+}$) 0.066, ($\\mathbb{C}a^{2+}$) 0.099, ($\\mathrm{Li^{+}}$) 0.066, ($\\mathbf{Fe}^{\\mathbf{2+}}$) 0.074) is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ca2+ due to its identical charge state and similar electronegativity", "B": "Li+ due to its identical ionic radius and lower charge density", "C": "Fe2+ due to its similar charge state and closest ionic radius", "D": "None of the above, as no cation can replace Mg2+ in MgO" }, "correct_answer": "C", "explanation": "The correct answer is C because Fe2+ has the same charge state as Mg2+ and the closest ionic radius (0.074 nm vs 0.066 nm), which is the most critical factor for substitution in ionic compounds. Option A is a cognitive bias trap - while Ca2+ has the same charge, its significantly larger radius (0.099 nm) would cause excessive lattice strain. Option B exploits intuitive similarity (same radius) but ignores the charge mismatch (Li+ is monovalent). Option D is an absolute statement trap that contradicts solid solution principles in ionic crystals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1192, "question": "What is the second type of temper brittleness?", "answer": "The brittleness that occurs during tempering between 450~650℃ is called high-temperature temper brittleness, also known as the second type of temper brittleness. The second type of temper brittleness is reversible. The main reason for its occurrence is that impurity elements such as Sb, Sn, P, and As segregate to the original austenite grain boundaries during tempering, weakening the atomic bonding force at the austenite grain boundaries and reducing the grain boundary fracture strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释第二类回火脆性的定义和原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对第二类回火脆性的定义、发生温度范围、可逆性以及主要原因等基本概念的记忆和理解，不涉及复杂的应用或分析过程。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确理解第二类回火脆性的定义、温度范围、可逆性以及产生原因等多个知识点。正确选项提供了较为详细的解释，考生需要将这些信息整合并选择正确的描述。相比于仅需记忆简单定义的等级1题目，该题目对概念的理解和描述要求更高，但尚未达到需要阐述复杂概念体系的等级3难度。", "convertible": true, "correct_option": "The brittleness that occurs during tempering between 450~650℃ is called high-temperature temper brittleness, also known as the second type of temper brittleness. The second type of temper brittleness is reversible. The main reason for its occurrence is that impurity elements such as Sb, Sn, P, and As segregate to the original austenite grain boundaries during tempering, weakening the atomic bonding force at the austenite grain boundaries and reducing the grain boundary fracture strength.", "choice_question": "Which of the following describes the second type of temper brittleness?", "conversion_reason": "The answer is a standard concept and can be converted into a multiple-choice question by presenting the correct description among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Reversible brittleness caused by impurity segregation at austenite grain boundaries during 450-650°C tempering", "B": "Irreversible brittleness due to carbide precipitation at martensite lath boundaries below 300°C", "C": "Brittleness resulting from retained austenite decomposition during cryogenic treatment", "D": "Temporary embrittlement caused by hydrogen absorption during electrochemical processing" }, "correct_answer": "A", "explanation": "Option A correctly describes the second type of temper brittleness (high-temperature temper brittleness) which is reversible and caused by impurity segregation. Option B describes the first type of temper brittleness (low-temperature). Option C is a distractor using cryogenic treatment which is unrelated. Option D describes hydrogen embrittlement, a completely different phenomenon. Advanced AIs might confuse the temperature ranges or reversibility characteristics between the two types of temper brittleness.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3419, "question": "Explain the meaning of the steel grade W6Mo5Cr4V2", "answer": "W6Mo5Cr4V2 is a high-speed steel, wc=0.85%, ww=6%, WMo=5%, wc=4%, wv=3%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释钢号W6Mo5Cr4V2的含义，答案提供了详细的文字解释和成分说明，符合简答题的特征。 | 知识层次: 题目考查对高速钢牌号W6Mo5Cr4V2的基本成分记忆和理解，属于基础概念的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目要求考生解释特定钢号的成分含义，属于概念解释和描述层次。虽然需要记忆具体的元素含量百分比，但不需要复杂的分析或比较，属于中等偏下的难度。", "convertible": true, "correct_option": "W6Mo5Cr4V2 is a high-speed steel, wc=0.85%, ww=6%, WMo=5%, wc=4%, wv=3%", "choice_question": "Which of the following correctly describes the steel grade W6Mo5Cr4V2?", "conversion_reason": "The answer is a standard description of the steel grade, which can be presented as a correct option among other plausible but incorrect descriptions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "W6Mo5Cr4V2 is a high-speed steel with 0.85% C, 6% W, 5% Mo, 4% Cr, and 2% V", "B": "W6Mo5Cr4V2 is a tool steel with 6% W, 5% Mo, 4% Cr, and 2% V, but no carbon content", "C": "W6Mo5Cr4V2 is a stainless steel with 6% W, 5% Mo, 4% Cr, and 2% V, similar to 316L but with tungsten", "D": "W6Mo5Cr4V2 is a high-speed steel with 6% W, 5% Mo, 4% Cr, and 2% V, where carbon content is implied but not specified" }, "correct_answer": "A", "explanation": "The correct answer is A because W6Mo5Cr4V2 is a standard high-speed steel grade where the numbers represent the percentage of alloying elements (W, Mo, Cr, V) and the carbon content (0.85%) is implied in the naming convention. Option B is incorrect because all high-speed steels contain carbon for hardness. Option C is a trap using stainless steel analogy which is fundamentally different from high-speed steel. Option D exploits the common oversight of carbon content specification in naming conventions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2815, "question": "A Gu–30%Zn brass plate is cold rolled by 25%, reducing its thickness to 1 cm. Subsequently, the plate is further reduced to a thickness of 0.6 cm. Calculate the total cold deformation degree.", "answer": "Cold deformation degree = (A0 - AF) / A0 × 100%, 25% = (h w - 1 w) / (h w) × 100%, h = 4/3 cm. Total deformation degree = (4/3 w - 0.6 w) / (4/3 w) × 100% = 55%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解总冷变形程度，答案涉及具体的数学运算和百分比计算。 | 知识层次: 题目需要进行多步计算，包括初始厚度的推导和总变形程度的计算，涉及公式的应用和综合分析，但不需要复杂的推理或机理解释。 | 难度: 在选择题中属于中等偏上难度，需要理解冷变形度的计算公式，并进行多步计算。题目涉及初始厚度计算、两次变形后的总变形度计算，需要综合应用材料科学中的变形概念和数学计算能力。虽然题目提供了部分计算步骤，但考生仍需正确理解并应用公式才能得出最终答案。", "convertible": true, "correct_option": "55%", "choice_question": "A Gu–30%Zn brass plate is cold rolled by 25%, reducing its thickness to 1 cm. Subsequently, the plate is further reduced to a thickness of 0.6 cm. What is the total cold deformation degree?", "conversion_reason": "The answer is a specific numerical value (55%), which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "55%", "B": "40%", "C": "64%", "D": "25%" }, "correct_answer": "A", "explanation": "正确答案55%的计算过程：初始厚度为1/(1-0.25)=1.333cm，最终厚度0.6cm，总变形=(1.333-0.6)/1.333=55%。干扰项B(40%)是简单相加25%和(1-0.6)/1=40%的错误结果，利用了认知偏差。干扰项C(64%)是直接计算(1.333-0.6)/1.333但错误保留小数位的结果。干扰项D(25%)只考虑第一次变形，忽略了后续加工，是专业直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2115, "question": "Point out the error in the following concept and correct it: For carbon steel of any composition, as the carbon content increases, the relative amount of ferrite in the structure decreases, while the relative amount of pearlite increases.", "answer": "For hypoeutectoid carbon steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择或判断。答案提供了具体的修正内容，属于简答题的特征。 | 知识层次: 题目要求识别并纠正一个关于碳钢组织变化的错误概念，需要理解碳钢的分类（亚共析钢、共析钢、过共析钢）及其组织变化规律，涉及多个概念的关联和综合分析。虽然不涉及复杂计算，但需要对材料科学中的相变和组织形成有较深入的理解，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解碳钢的组成与相变关系，并能区分亚共析钢和过共析钢的不同行为。题目要求识别概念错误并给出正确限定条件，涉及多步概念关联和综合分析能力。", "convertible": true, "correct_option": "For hypoeutectoid carbon steel", "choice_question": "Which of the following correctly identifies the scope of the statement: 'For carbon steel of any composition, as the carbon content increases, the relative amount of ferrite in the structure decreases, while the relative amount of pearlite increases.'?", "conversion_reason": "The original short answer question asks for a correction to a concept, and the answer is a standard term ('For hypoeutectoid carbon steel'). This can be converted into a multiple-choice question by asking which option correctly identifies the scope of the statement.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "For hypoeutectoid carbon steel only", "B": "For all carbon steels including hypereutectoid compositions", "C": "Only when cooling rate exceeds 100°C/s", "D": "When carbon content is below 0.02 wt%" }, "correct_answer": "A", "explanation": "The correct scope is hypoeutectoid steel (A) because the statement only holds true below the eutectoid composition (0.76 wt% C). For hypereutectoid steels (B), increasing carbon increases cementite, not pearlite. Option C exploits cooling rate confusion, while D targets the ultra-low carbon range where the statement doesn't apply. Advanced AIs may incorrectly generalize to all carbon steels (B) due to pattern matching with common phase diagram explanations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 76, "question": "What is the effect on lattice activation after forming a solid solution?", "answer": "Activating the lattice, after forming a solid solution, the lattice structure undergoes certain distortion and is in a high-energy activated state, which is conducive to chemical reactions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释固体溶液形成后对晶格活化的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及固体溶液形成后晶格激活效应的解释，需要理解晶格畸变与高能激活状态之间的关系，并能够综合分析其对化学反应的影响。这属于中等应用层次，需要将多个概念关联起来进行解释，但不需要进行复杂的机理分析或创新设计。 | 难度: 在选择题中属于中等难度，需要理解固溶体形成后晶格结构的变化及其对化学反应的影响，涉及概念关联和综合分析。", "convertible": true, "correct_option": "Activating the lattice, after forming a solid solution, the lattice structure undergoes certain distortion and is in a high-energy activated state, which is conducive to chemical reactions.", "choice_question": "What is the effect on lattice activation after forming a solid solution?", "conversion_reason": "The answer is a standard description of the effect on lattice activation after forming a solid solution, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The lattice distortion increases activation energy due to strain fields", "B": "The lattice maintains its original activation state with no significant change", "C": "The solid solution decreases activation energy by introducing defects", "D": "The activation state depends solely on the solute concentration" }, "correct_answer": "C", "explanation": "The correct answer is C because forming a solid solution introduces lattice distortions and defects which lower the activation energy barrier for chemical reactions. Option A is a cognitive bias trap - while strain fields exist, they actually decrease activation energy. Option B exploits the common misconception that solid solutions are 'perfect' mixtures. Option D is a partial truth trap - while concentration affects activation, it's not the sole factor as lattice distortion plays a key role.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1893, "question": "Wetting is an important behavior at the solid-liquid interface, one of the methods to improve wetting is (18)", "answer": "Changing surface roughness", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求提供一个简短但具体的答案（\"Changing surface roughness\"），而不是从多个选项中选择或进行判断或计算。这种形式更符合简答题的特征。 | 知识层次: 题目考查对润湿行为及其改善方法的基础概念记忆，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需考生记住改善润湿性的一种方法即可作答，无需进行复杂的概念解释或分析。题目直接给出了正确选项，且知识点较为单一，属于选择题中最简单的难度等级。", "convertible": true, "correct_option": "Changing surface roughness", "choice_question": "Which of the following is a method to improve wetting at the solid-liquid interface?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Changing surface roughness", "B": "Increasing elastic modulus of the solid", "C": "Applying hydrostatic pressure to the liquid", "D": "Reducing the liquid's thermal conductivity" }, "correct_answer": "A", "explanation": "Changing surface roughness (A) directly affects the solid-liquid interface energy and contact angle, improving wetting. Increasing elastic modulus (B) is a cognitive bias trap - while stiffness affects mechanical properties, it has negligible impact on interfacial wetting. Applying hydrostatic pressure (C) is a professional intuition trap - pressure affects bulk properties but not interfacial energetics. Reducing thermal conductivity (D) is a multi-level verification trap - it seems related to heat transfer at interfaces but is irrelevant to wetting thermodynamics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3491, "question": "Can austenitic stainless steel be strengthened by heat treatment?", "answer": "No. Because after quenching (solution treatment), austenitic stainless steel undergoes no phase transformation, and all second-phase particles dissolve into the austenite. As a result, its hardness and strength drop to the lowest level after quenching, so it cannot be strengthened by heat treatment.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（Can austenitic stainless steel be strengthened by heat treatment?），而答案明确给出了判断结果（No）并提供了简要解释。这符合判断题的特征，即判断陈述的对错并提供简要说明。 | 知识层次: 题目考查对奥氏体不锈钢热处理强化原理的基础概念记忆和理解，无需复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度等级。题目考察的是对奥氏体不锈钢热处理强化原理的理解，需要学生掌握奥氏体不锈钢在淬火后的相变行为和强化机制。虽然涉及专业概念，但只需判断一个基本原理的正确性，不需要进行复杂的概念比较或综合分析。", "convertible": true, "correct_option": "No. Because after quenching (solution treatment), austenitic stainless steel undergoes no phase transformation, and all second-phase particles dissolve into the austenite. As a result, its hardness and strength drop to the lowest level after quenching, so it cannot be strengthened by heat treatment.", "choice_question": "Can austenitic stainless steel be strengthened by heat treatment?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "Austenitic stainless steels can always be strengthened through conventional heat treatment processes like quenching and tempering.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because austenitic stainless steels cannot be strengthened by conventional heat treatment. The key misconception is the use of 'always' - while some stainless steels can be heat treated, austenitic grades maintain their austenitic structure even after quenching due to high nickel content, preventing phase transformation. The correct strengthening methods for austenitic stainless steels are work hardening or precipitation hardening (for specific grades). The absolute term 'always' makes this definitively false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 176, "question": "What is the difference between surface tension and surface energy in the liquid state?", "answer": "Liquid: cannot withstand shear stress, the work done by external forces manifests as an expansion of surface area, because surface tension and surface energy are numerically the same", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释表面张力和表面能之间的区别，答案提供了文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查表面张力和表面能的基本概念及其在液态下的关系，属于基础概念的记忆和理解。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆，但需要考生理解并区分表面张力和表面能量这两个相关但不同的概念。正确选项要求考生能够识别在液态状态下这两个物理量的数值关系，这超出了简单定义记忆的范畴，属于概念解释和描述的层次。不过题目没有涉及复杂的推导或多概念整合，因此不属于最高难度等级。", "convertible": true, "correct_option": "Liquid: cannot withstand shear stress, the work done by external forces manifests as an expansion of surface area, because surface tension and surface energy are numerically the same", "choice_question": "What is the difference between surface tension and surface energy in the liquid state?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Surface tension is a force per unit length while surface energy is energy per unit area, but they are numerically identical for liquids due to their inability to withstand shear stress", "B": "Surface tension arises from intermolecular forces while surface energy is the work required to create new surface, making them fundamentally different quantities", "C": "Surface tension applies only to liquids while surface energy is a property of both solids and liquids, with different units of measurement", "D": "Surface energy represents potential energy stored at interfaces while surface tension is kinetic energy of surface molecules, leading to different numerical values" }, "correct_answer": "A", "explanation": "The correct answer A identifies the key distinction in units while correctly stating their numerical equivalence in liquids. Option B creates confusion by suggesting they are fundamentally different quantities. Option C exploits the solids vs liquids distinction but incorrectly implies different units. Option D introduces false energy-type differentiation that doesn't exist in reality.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2889, "question": "What is a homopolymer?", "answer": "A polymer formed by the polymerization of a single monomer is called a homopolymer.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"homopolymer\"进行定义和解释，答案以文字形式给出，属于简答题类型。 | 知识层次: 题目考查对聚合物基本分类的记忆和理解，仅需回答单一概念的定义，不涉及应用或分析。 | 难度: 在选择题型中，该题目仅要求记忆并识别“homopolymer”的基本定义，属于基础概念记忆的简单题目。正确选项直接给出了定义，无需复杂推理或比较分析，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "A polymer formed by the polymerization of a single monomer is called a homopolymer.", "choice_question": "Which of the following best defines a homopolymer?", "conversion_reason": "The answer is a standard definition that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A polymer formed by the polymerization of a single monomer", "B": "A copolymer with identical repeating units along the backbone", "C": "A polymer blend with uniform molecular weight distribution", "D": "A dendritic polymer with homogeneous branching" }, "correct_answer": "A", "explanation": "The correct answer is A because a homopolymer is strictly defined as a polymer formed from a single monomer species. Option B is incorrect because copolymers by definition contain multiple monomer types, even if segments appear identical. Option C describes a polymer blend property unrelated to monomer composition. Option D refers to a specific architecture of branched polymers, not monomer homogeneity.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4839, "question": "At room temperature the electrical conductivity and the electron mobility for aluminum are 3.8 x 10^7 (Ω·m)^-1 and 0.0012 m^2/V·s, respectively. What is the number of free electrons per aluminum atom? Assume a density of 2.7 g/cm^3.", "answer": "the number of free electrons per aluminum atom is 3.28 electrons/al atom.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定每个铝原子中的自由电子数量。答案是一个具体的数值结果，而不是选择、判断或文字解释。 | 知识层次: 题目需要进行多步计算，涉及电导率、电子迁移率和密度的概念关联，以及自由电子数的综合分析。虽然不涉及复杂的推理或机理解释，但需要一定的计算能力和概念理解。 | 难度: 在选择题中属于中等偏上难度，需要综合运用电导率、电子迁移率、密度等概念，并进行多步计算才能得出结果。虽然题目提供了所有必要数据，但解题过程涉及单位转换、公式推导和综合分析能力，对学生的知识掌握深度和计算能力要求较高。", "convertible": true, "correct_option": "3.28 electrons/al atom", "choice_question": "At room temperature the electrical conductivity and the electron mobility for aluminum are 3.8 x 10^7 (Ω·m)^-1 and 0.0012 m^2/V·s, respectively. Assuming a density of 2.7 g/cm^3, what is the number of free electrons per aluminum atom?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "3.28 electrons/al atom", "B": "1.00 electron/al atom", "C": "4.12 electrons/al atom", "D": "2.71 electrons/al atom" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula n = σ/(eμ), where σ is conductivity, e is electron charge, and μ is mobility. Then dividing by the atomic density gives free electrons per atom. Option B exploits the common misconception that each Al atom contributes exactly 1 free electron. Option C is derived by incorrectly using atomic mass instead of density in the calculation. Option D is designed to match the material density value (2.7 g/cm³) to mislead those who confuse density with electron contribution.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1906, "question": "Unit parallelepiped", "answer": "Unit parallelepiped: In a space lattice, the parallelepiped selected according to the selection principle is called the unit parallelepiped.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Unit parallelepiped\"进行文字解释和论述，答案提供了概念的定义和说明，符合简答题的特征。 | 知识层次: 题目考查对\"Unit parallelepiped\"这一基本概念的定义记忆，属于空间点阵中的基础概念，不涉及应用或分析过程 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"unit parallelepiped\"的基本定义，属于最基础的概念记忆层次。题目直接给出了定义描述，不需要进行任何解释、比较或分析，完全符合等级1\"基本定义简答\"的标准。在选择题型内，这是最简单的难度级别，只需对专业术语的定义有基本记忆即可正确作答。", "convertible": true, "correct_option": "Unit parallelepiped: In a space lattice, the parallelepiped selected according to the selection principle is called the unit parallelepiped.", "choice_question": "Which of the following correctly defines a unit parallelepiped?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct definition among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In a space lattice, the parallelepiped selected according to the selection principle is called the unit parallelepiped", "B": "A parallelepiped with edge lengths equal to the lattice parameters in all three dimensions", "C": "The smallest repeating unit that can generate the entire crystal structure through translation", "D": "A parallelepiped containing exactly one lattice point when centered on that point" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines the unit parallelepiped as being selected based on specific crystallographic principles. Option B is a common misconception that unit cells must have edges equal to lattice parameters. Option C incorrectly describes a primitive unit cell rather than a unit parallelepiped. Option D is a tempting but incorrect definition that applies only to certain centered lattices.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4667, "question": "One crystalline form of silica \\left(\\mathrm{SiO}_{2}\\right) has a cubic unit cell, and from x-ray diffraction data it is known that the cell edge length is 0.700nm. If the measured density is 2.32g / {cm}^{3}, how many \\mathrm{Si}^{4+} and \\mathrm{O}^{2}-ions are there per unit cell?", "answer": "there are 8 \\mathrm{si}^{4+} ions and 16 \\mathrm{o}^{2-} ions per \\mathrm{sio}_{2} unit cell.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解单位晶胞中的离子数量，涉及密度、晶胞边长等物理量的计算，答案也是具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括单位转换、密度公式应用以及离子数量的推导，涉及概念关联和综合分析，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要综合运用晶体结构、密度计算和化学计量比的知识。解题步骤包括：", "convertible": true, "correct_option": "there are 8 Si⁴⁺ ions and 16 O²⁻ ions per SiO₂ unit cell.", "choice_question": "One crystalline form of silica (SiO₂) has a cubic unit cell with a cell edge length of 0.700 nm. If the measured density is 2.32 g/cm³, how many Si⁴⁺ and O²⁻ ions are there per unit cell?", "conversion_reason": "The question is a calculation problem with a specific and definitive answer, making it suitable for conversion into a multiple-choice format. The correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8 Si⁴⁺ and 16 O²⁻ ions", "B": "4 Si⁴⁺ and 8 O²⁻ ions", "C": "12 Si⁴⁺ and 24 O²⁻ ions", "D": "6 Si⁴⁺ and 12 O²⁻ ions" }, "correct_answer": "A", "explanation": "The correct answer is A because the given density and unit cell dimensions correspond to the cubic cristobalite structure of SiO₂, which has 8 formula units per unit cell (Z=8). Each formula unit contains 1 Si⁴⁺ and 2 O²⁻ ions, resulting in 8 Si⁴⁺ and 16 O²⁻ ions per unit cell. Option B is a common mistake based on assuming a simpler cubic structure with Z=4. Option C exploits the tendency to overcount in face-centered cubic arrangements. Option D is designed to trap those who incorrectly correlate the coordination number (6 for Si in SiO₂) with the unit cell content.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2731, "question": "Given the stacking fault energy Y=0.01 J/m², shear modulus G=7 × 10^10 Pa, lattice constant α=0.3 nm, Poisson's ratio v=0.3 for an fcc crystal, determine the equilibrium separation distance between the two partial dislocations $\\frac{a}{6}[11\\vec{2}]$ and $\\frac{a}{6}[2\\overline{{{1}}}\\overline{{{1}}}]$.", "answer": "$d_{\\mathrm{s}}\\approx\\frac{G b^{\\mathrm{2}}}{24\\pi\\gamma}$ $b{=}{\\frac{a}{n}}{\\sqrt{1^{2}+1^{2}+2^{2}}}{=}{\\frac{\\sqrt{6}}{6}}a,$ $$ d_{*}\\approx\\frac{7\\times10^{10}\\times\\frac{1}{6}\\times(0.3\\times10^{-9})^{2}}{24\\times3.1416\\times0.01}=1.3926\\times10^{-9}(\\mathrm{m})$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的材料参数和公式进行数值计算，最终得出一个具体的数值结果。答案中包含了详细的公式推导和计算步骤，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要理解位错理论、堆垛层错能、剪切模量等概念，并应用相关公式进行综合分析。虽然不涉及复杂的推理分析或创新应用，但需要一定的思维深度和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如堆垛层错能、剪切模量、晶格常数、泊松比等）并进行多步骤计算。题目要求考生能够正确应用公式并代入数值进行计算，同时需要理解位错分离距离的物理意义。虽然题目提供了公式，但计算过程涉及多个变量和单位转换，对考生的综合计算能力和概念掌握有一定要求。", "convertible": true, "correct_option": "1.3926×10⁻⁹ m", "choice_question": "Given the stacking fault energy Y=0.01 J/m², shear modulus G=7 × 10^10 Pa, lattice constant α=0.3 nm, Poisson's ratio v=0.3 for an fcc crystal, the equilibrium separation distance between the two partial dislocations $\\frac{a}{6}[11\\vec{2}]$ and $\\frac{a}{6}[2\\overline{{{1}}}\\overline{{{1}}}]$ is approximately:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a choice among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.3926×10⁻⁹ m", "B": "2.7852×10⁻⁹ m", "C": "6.963×10⁻¹⁰ m", "D": "3.4815×10⁻⁹ m" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the formula for equilibrium separation distance d = G*b₁*b₂/(2πY), where b₁ and b₂ are the Burgers vectors of the partial dislocations. Option B is a cognitive bias trap that doubles the correct value, exploiting the common mistake of missing the 1/2 factor in the denominator. Option C is a half-value trap that divides the correct answer by 2, targeting those who might confuse the formula with simple proportionality. Option D is a professional intuition trap that provides the value one would get if incorrectly using the full dislocation Burgers vector instead of partial dislocations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2745, "question": "Calculate the change in the melting point of tin when the pressure increases to $500\\\\times10^{5}\\\\mathbf{Pa}$. It is known that at $\\\\mathfrak{10}^{5}\\\\mathbf{Pa}$, the melting point of tin is $505~\\\\mathrm{K}$, the heat of fusion is $7196\\\\mathrm{J/mol}$, the molar mass is $118.8\\\\times10^{-3}~\\\\mathrm{kg/mol}$, the density of solid tin is $\\\\small7.30\\\\times10^{3}~\\\\mathrm{kg/m^{3}}$, and the volume change during melting is $+2.7\\\\%$.", "answer": "The molar volume of tin $$ V_{\\\\mathrm{m}}={\\\\mathrm{molar mass}}/\\\\mathrm{density}={\\\\frac{118.7\\\\times10^{-3}}{7.30\\\\times10^{3}}}=1.626\\\\times10^{-5}(\\\\mathrm{m}^{3}/\\\\mathrm{mol})$$ $$ \\\\begin{array}{r}{\\\\Delta V_{\\\\mathrm{m}}=0.027\\\\times1.626\\\\times10^{-5}}\\\\\\\\ {=4.39\\\\times10^{-7}\\\\left(\\\\mathrm{m}^{3}/\\\\mathrm{mol}\\\\right)}\\\\end{array}$$ Assuming $\\\\Delta V_{\\\\mathfrak{m}}$ and $\\\\Delta H_{\\\\pmb{\\\\upmu}}$ remain constant within the considered temperature range, and $\\\\Delta T{\\\\ll}T$ $$ \\\\begin{array}{c}{{\\\\frac{\\\\Delta\\\\phi}{\\\\Delta T}=\\\\frac{\\\\Delta H_{\\\\mathrm{m}}}{T\\\\cdot\\\\Delta V_{\\\\mathrm{m}}}=\\\\frac{7196}{505\\\\times4.39\\\\times10^{-7}}}}\\\\\\\\ {{=3.25\\\\times10^{7}(\\\\mathrm{N}\\\\cdot\\\\mathrm{m}^{-2}\\\\cdot\\\\mathrm{K}^{\\\\mathrm{\\\\Delta_{\\\\parallel}}})}}\\\\end{array}$$ Then $$ \\\\Delta T={\\\\frac{(500-1)\\\\times10^{5}}{3.25\\\\times10^{7}}}=1.54(\\\\mathrm{K})$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解锡的熔点变化，答案中包含了详细的数学推导和计算结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要应用克劳修斯-克拉珀龙方程进行压力对熔点影响的计算，并理解相关物理量的含义和相互关系。虽然不涉及复杂的推理分析或创新应用，但需要综合运用多个知识点进行中等难度的计算。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如摩尔体积、热力学关系）并进行多步骤计算（包括单位转换、比例计算和公式应用）。虽然题目提供了所有必要数据，但解题过程涉及多个物理量的综合运用和近似假设，对学生的综合分析能力有一定要求。", "convertible": true, "correct_option": "1.54 K", "choice_question": "Calculate the change in the melting point of tin when the pressure increases to $500\\times10^{5}\\mathbf{Pa}$. It is known that at $\\mathfrak{10}^{5}\\mathbf{Pa}$, the melting point of tin is $505~\\mathrm{K}$, the heat of fusion is $7196\\mathrm{J/mol}$, the molar mass is $118.8\\times10^{-3}~\\mathrm{kg/mol}$, the density of solid tin is $\\small7.30\\times10^{3}~\\mathrm{kg/m^{3}}$, and the volume change during melting is $+2.7\\%$. The change in melting point is:", "conversion_reason": "The calculation yields a specific numerical answer (1.54 K), which can be presented as a correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.54 K", "B": "0.77 K", "C": "3.08 K", "D": "-1.54 K" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Clausius-Clapeyron equation considering the 2.7% volume expansion during melting. Option B is half the correct value, exploiting the common mistake of not properly accounting for the percentage volume change. Option C doubles the correct value, targeting those who might misinterpret the pressure scaling factor. Option D reverses the sign, playing on the misconception that increased pressure always decreases melting points (true for water but not most metals). The subtlety in correctly converting the percentage volume change to absolute values while maintaining proper units creates a multi-layered verification challenge.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 870, "question": "What are the three typical zones of a metal ingot structure?", "answer": "Chill zone, columnar crystal zone, and equiaxed crystal zone.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举金属铸锭结构的三个典型区域，答案是以文字形式简要列出具体区域名称，不需要计算或选择，符合简答题的特征 | 知识层次: 题目考查金属铸锭结构的三个典型区域的基本概念记忆，属于基础概念记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求识别金属铸锭结构的三个典型区域名称，属于基础概念记忆层面。题目仅需回忆定义性知识，无需解释或分析，解题步骤简单直接，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Chill zone, columnar crystal zone, and equiaxed crystal zone", "choice_question": "Which of the following are the three typical zones of a metal ingot structure?", "conversion_reason": "The answer is a standard set of terms that can be presented as a correct option among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chill zone, columnar crystal zone, and equiaxed crystal zone", "B": "Nucleation zone, dendritic growth zone, and homogenization zone", "C": "Surface zone, transition zone, and core zone", "D": "Deformation zone, recrystallization zone, and grain growth zone" }, "correct_answer": "A", "explanation": "The correct answer is A because these are the three distinct structural zones formed during solidification of metal ingots. Option B uses plausible-sounding but incorrect terminology for ingot solidification. Option C describes general structural divisions that could apply to many materials but not the specific crystallization zones. Option D refers to zones formed during thermomechanical processing rather than solidification, exploiting confusion between different metallurgical processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 893, "question": "A single crystal test bar of an FCC metal with a cross-sectional area of 10cm² is subjected to a compression test along the axial direction. Given that the critical resolved shear stress is 0.1kgf/mm² and the initial orientation of the bar axis is [215], determine the axial pressure P at the onset of double slip (without considering physical hardening).", "answer": "P = (0.1×1000)/((√10/5)×(√10/5))×9.8N = 2450N.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定轴向压力P的值，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要理解临界分切应力、晶体取向、双滑移条件等概念，并进行综合分析和计算。 | 难度: 在选择题中属于中等偏上难度，需要理解临界分切应力、晶体取向与滑移系的关系，并进行多步骤的单位换算和向量计算。虽然题目提供了关键公式，但需要综合应用材料力学和晶体学知识才能正确求解。", "convertible": true, "correct_option": "2450N", "choice_question": "A single crystal test bar of an FCC metal with a cross-sectional area of 10cm² is subjected to a compression test along the axial direction. Given that the critical resolved shear stress is 0.1kgf/mm² and the initial orientation of the bar axis is [215], determine the axial pressure P at the onset of double slip (without considering physical hardening). The axial pressure P is:", "conversion_reason": "该计算题的答案是确定的数值，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2450N", "B": "1225N", "C": "4900N", "D": "980N" }, "correct_answer": "A", "explanation": "正确答案A是通过正确计算Schmid因子并应用临界分切应力得到的。干扰项B错误地假设了单滑移条件，利用了认知偏差。干扰项C通过错误地使用最大Schmid因子设计，利用了专业直觉陷阱。干扰项D则通过单位换算错误(kgf→N)制造了多层次验证陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1551, "question": "4.Coordination number", "answer": "The number of nearest neighbor atoms around any lattice node atom in the crystal lattice.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Coordination number\"进行文字解释和论述，答案是一个定义性的陈述，而不是选择、判断或计算。 | 知识层次: 题目考查基本概念的记忆和理解，即晶体结构中配位数的定义，属于基础概念记忆性知识。 | 难度: 在选择题型中，此题仅考查对\"配位数\"这一基础概念的定义记忆，属于最基础的知识点掌握要求。正确选项直接给出了晶体结构中配位数的明确定义，不需要任何解释、比较或分析过程，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "The number of nearest neighbor atoms around any lattice node atom in the crystal lattice.", "choice_question": "What is the coordination number in a crystal lattice?", "conversion_reason": "The answer is a standard definition of a term, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The number of nearest neighbor atoms around any lattice node atom", "B": "The total number of atoms in the unit cell", "C": "The number of bonds formed by the central atom in a molecule", "D": "The maximum number of electron pairs in the valence shell" }, "correct_answer": "A", "explanation": "The correct answer is A because coordination number specifically refers to the count of nearest neighbor atoms in a crystal lattice. Option B is a common confusion with unit cell content counting. Option C exploits molecular chemistry knowledge crossover. Option D targets quantum chemistry concept confusion by referencing electron pair geometry.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3635, "question": "Based on the zinc blende structure of BeO, determine the packing factor.", "answer": "The packing factor is 0.684.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求基于闪锌矿结构的BeO计算其堆积因子，需要应用相关公式进行数值计算，最终给出具体的数值结果0.684。 | 知识层次: 题目需要理解锌矿结构（BeO）的晶体结构特点，并应用几何关系计算堆积因子。这涉及多步计算和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解锌矿结构的基本概念，掌握晶格参数与原子半径的关系，并正确应用堆积因子的计算公式。题目涉及多步计算和概念关联，但选项已给出正确结果，减少了部分计算复杂度。", "convertible": true, "correct_option": "0.684", "choice_question": "Based on the zinc blende structure of BeO, what is the packing factor?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.684", "B": "0.740", "C": "0.625", "D": "0.520" }, "correct_answer": "A", "explanation": "The correct answer is 0.684 because the zinc blende structure has a packing factor of √3π/16. Option B (0.740) is the packing factor for FCC and HCP structures, exploiting the common confusion between close-packed and zinc blende structures. Option C (0.625) mimics a simple cubic structure value, targeting incorrect dimensional assumptions. Option D (0.520) represents a distorted value from diamond cubic structures, leveraging the visual similarity between zinc blende and diamond cubic arrangements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2, "question": "What are the parameters used to qualitatively describe crystal structures?", "answer": "Symmetry axes, symmetry center, crystal system, lattice.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过文字解释和论述来回答，答案是一系列描述晶体结构的参数，而不是选择、判断或计算。 | 知识层次: 题目考查对晶体结构定性描述参数的基本概念记忆和理解，包括对称轴、对称中心、晶系和晶格等基础知识点，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别晶体结构的定性描述参数（对称轴、对称中心、晶系、晶格），属于基础概念的直接回忆，无需解释或复杂分析，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "Symmetry axes, symmetry center, crystal system, lattice", "choice_question": "Which of the following are parameters used to qualitatively describe crystal structures?", "conversion_reason": "The answer is a standard set of terms that can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Symmetry axes, symmetry center, crystal system, lattice", "B": "Young's modulus, Poisson's ratio, hardness, density", "C": "Dislocation density, grain size, stacking fault energy, Burgers vector", "D": "Melting point, thermal conductivity, electrical resistivity, specific heat" }, "correct_answer": "A", "explanation": "The correct answer is A because symmetry axes, symmetry center, crystal system, and lattice are fundamental qualitative descriptors of crystal structures. Option B exploits cognitive bias by listing well-known material properties that are quantitative, not qualitative descriptors. Option C is a professional intuition trap using microstructural features that describe defects rather than the perfect crystal structure. Option D is a multi-level verification trap presenting bulk material properties that, while important, do not describe the crystal structure itself.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3905, "question": "Some metal is known to have a cubic unit cell with an edge length of 0.437 nm. In addition, it has a density of 4.37 g/cm3 and an atomic weight of 54.85 g/mol. Determine the crystal structure of the metal.", "answer": "The metal has an FCC crystal structure.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来确定金属的晶体结构，涉及单位晶胞边长、密度和原子量等参数的计算，最终得出FCC晶体结构的结论。 | 知识层次: 题目需要多步计算（包括密度公式应用、单位换算、晶体结构判断），涉及概念关联（晶胞参数、密度、原子量之间的关系），并需要综合分析计算结果来确定晶体结构类型。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生通过给定的晶胞边长、密度和原子量，计算并确定金属的晶体结构。这涉及到多步计算（如计算晶胞中的原子数）和概念关联（如理解FCC、BCC等晶体结构的特点）。虽然题目提供了所有必要的信息，但解题过程需要综合应用多个知识点，并进行一定的推理判断，因此在选择题型中属于中等偏上的难度。", "convertible": true, "correct_option": "The metal has an FCC crystal structure.", "choice_question": "A metal is known to have a cubic unit cell with an edge length of 0.437 nm, a density of 4.37 g/cm3, and an atomic weight of 54.85 g/mol. Determine the crystal structure of the metal.", "conversion_reason": "The answer is a standard term (FCC crystal structure), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The metal has an FCC crystal structure", "B": "The metal has a BCC crystal structure", "C": "The metal has a simple cubic crystal structure", "D": "The metal has a HCP crystal structure" }, "correct_answer": "A", "explanation": "The correct answer is A because the calculated number of atoms per unit cell (4) matches the FCC structure. Option B is a cognitive bias trap - the density value is close to typical BCC metals but the calculation disproves it. Option C exploits the 'simplest solution' intuition error - while the edge length might suggest simple cubic, the density calculation shows it's too high. Option D is a professional intuition trap - HCP has similar packing factor to FCC but cannot exist in cubic systems, a subtle distinction many models miss.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1180, "question": "During austenite nucleation, not only (10) fluctuations and (11) fluctuations are required, but also (12) fluctuations are needed", "answer": "(10) structure; (11) energy; (12) composition", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写特定的术语（structure, energy, composition）来完成句子，这需要学生对相关概念有准确的理解和记忆，属于简答题的范畴。虽然形式上类似于填空题，但更侧重于对知识点的简短回答而非选择或判断。 | 知识层次: 题目考查对奥氏体形核过程中所需波动类型的基础概念记忆，包括结构、能量和成分波动，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需回忆奥氏体形核过程中所需的结构、能量和成分波动这三个基本定义。题目直接给出了正确选项，没有复杂的推理或分析步骤，因此属于最简单的难度等级。", "convertible": true, "correct_option": "structure; energy; composition", "choice_question": "During austenite nucleation, not only (10) fluctuations and (11) fluctuations are required, but also (12) fluctuations are needed. Which of the following correctly fills in the blanks (10), (11), and (12)?", "conversion_reason": "The short answer question has a standard and specific answer that can be converted into a multiple-choice format by providing the correct combination of terms as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "structure; energy; composition", "B": "energy; composition; stress", "C": "composition; temperature; pressure", "D": "temperature; entropy; free energy" }, "correct_answer": "A", "explanation": "The correct answer is A because austenite nucleation requires fluctuations in structure (to form the new phase), energy (to overcome the energy barrier), and composition (to achieve the required solute distribution). Option B incorrectly includes stress fluctuations, which are not fundamental to nucleation. Option C introduces temperature and pressure, which are external parameters rather than intrinsic fluctuations. Option D uses thermodynamic terms (entropy, free energy) that describe system states but not the required local fluctuations for nucleation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1826, "question": "What type of diffusion problem does Fick's first law apply to?", "answer": "Steady-state diffusion", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释和论述Fick's第一定律适用的扩散问题类型，答案\"Steady-state diffusion\"是一个简短的文字回答，不需要计算或选择选项。 | 知识层次: 题目考查Fick第一定律适用的扩散类型，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对Fick第一定律适用条件的基础定义记忆，属于最基础的概念性知识。学生只需识别\"稳态扩散\"这一关键词即可作答，无需任何解释或分析步骤，因此属于难度等级1。", "convertible": true, "correct_option": "Steady-state diffusion", "choice_question": "To which type of diffusion problem does Fick's first law apply?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Steady-state diffusion", "B": "Non-steady-state diffusion with time-dependent boundary conditions", "C": "Anisotropic diffusion in single crystals", "D": "Concentration-dependent diffusivity systems" }, "correct_answer": "A", "explanation": "Fick's first law strictly applies to steady-state diffusion where the concentration gradient does not change with time. Option B exploits the common confusion between Fick's first and second laws, where the latter handles time-dependent cases. Option C targets the misconception that crystallographic anisotropy affects the fundamental applicability of Fick's first law. Option D creates a trap by suggesting the law fails when diffusivity varies with concentration, when in fact it can still be applied locally at each concentration.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3396, "question": "After the wire drawing die made of high-carbon high-chromium steel wears out, the inner hole has a slight oversize. What heat treatment can be used to reduce the inner hole diameter?", "answer": "Water quenching.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述使用何种热处理方法来减小内孔直径，答案需要文字解释和论述，而不是从多个选项中选择或简单的对错判断。 | 知识层次: 题目要求根据特定材料（高碳高铬钢）和特定情况（拉丝模内孔轻微超差）选择合适的淬火工艺（水淬），需要理解材料的热处理原理和工艺选择的基本知识，并能够将理论知识应用于具体问题中。这涉及到多步思考和概念关联，但不需要复杂的分析或创新设计。 | 难度: 在选择题中属于中等难度，需要理解高碳高铬钢的热处理特性以及拉丝模具磨损后的修复方法。题目要求考生综合分析材料的热处理工艺（如水淬）对尺寸变化的影响，并关联到实际应用场景中的问题解决。虽然不需要多步计算，但需要对材料科学和热处理工艺有较深的理解才能正确选择水淬作为解决方案。", "convertible": true, "correct_option": "Water quenching", "choice_question": "After the wire drawing die made of high-carbon high-chromium steel wears out, the inner hole has a slight oversize. What heat treatment can be used to reduce the inner hole diameter?", "conversion_reason": "The answer is a standard term (Water quenching) which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Water quenching", "B": "Annealing at 750°C followed by slow cooling", "C": "Tempering at 300°C for 2 hours", "D": "Nitriding at 500°C for 5 hours" }, "correct_answer": "A", "explanation": "Water quenching is correct because the rapid cooling causes martensitic transformation in high-carbon high-chromium steel, resulting in volume expansion that reduces the inner hole diameter. Option B is a cognitive bias trap - annealing would soften the material but increase hole size due to stress relief. Option C exploits professional intuition - tempering does adjust dimensions but cannot reverse oversizing. Option D is a multi-level trap - while nitriding improves surface hardness, it causes negligible dimensional changes in this context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2694, "question": "What are the main differences between amorphous and crystalline substances in terms of internal atomic arrangement and properties?", "answer": "From the perspective of internal atomic arrangement, the fundamental characteristic of a crystalline structure is that atoms are arranged periodically in three-dimensional space, exhibiting long-range order, whereas the atomic arrangement in amorphous materials lacks long-range order. In terms of properties, crystals have fixed melting points and anisotropy, while amorphous materials do not have fixed melting points and are isotropic.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释非晶态和晶态物质在内部原子排列和性质上的主要差异，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对非晶态和晶态物质内部原子排列和性质差异的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目要求考生理解和比较两种材料（非晶态和晶态）的内部原子排列和性质差异。虽然涉及多个概念（长程有序、各向异性等），但题目提供了明确的对比框架，且正确选项直接总结了这些差异，不需要复杂的推理或分析步骤。因此，在选择题型内属于中等难度（等级2），主要考察概念解释和描述能力。", "convertible": true, "correct_option": "From the perspective of internal atomic arrangement, the fundamental characteristic of a crystalline structure is that atoms are arranged periodically in three-dimensional space, exhibiting long-range order, whereas the atomic arrangement in amorphous materials lacks long-range order. In terms of properties, crystals have fixed melting points and anisotropy, while amorphous materials do not have fixed melting points and are isotropic.", "choice_question": "Which of the following correctly describes the main differences between amorphous and crystalline substances in terms of internal atomic arrangement and properties?", "conversion_reason": "The answer is a standard description that can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description among given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystalline materials exhibit long-range atomic order and sharp melting points, while amorphous materials show short-range order only and undergo glass transition", "B": "Both crystalline and amorphous materials have long-range atomic order, but only crystals show anisotropic properties due to their perfect lattice symmetry", "C": "Amorphous materials actually possess hidden crystalline domains that explain their mechanical properties, while perfect crystals are purely theoretical constructs", "D": "The key difference is that crystalline materials always have higher density than amorphous forms of the same composition due to more efficient atomic packing" }, "correct_answer": "A", "explanation": "Option A correctly states the fundamental differences: crystalline materials have long-range order and sharp melting points, while amorphous materials only have short-range order and exhibit glass transition behavior. Option B is incorrect because amorphous materials lack long-range order. Option C is a trap using the partially correct concept of nanocrystalline domains but incorrectly applying it to all amorphous materials. Option D exploits the common misconception about density differences, while in reality some amorphous materials can be denser than their crystalline counterparts (e.g., amorphous ice).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3255, "question": "What is called secondary recrystallization?", "answer": "The growth of grains after recrystallization is further divided into normal growth and abnormal growth. The abnormal growth of grains is also called discontinuous growth or secondary recrystallization. Secondary recrystallization is a special mode of grain growth where the growth of most grains in the matrix is suppressed, while a few grains grow rapidly, significantly increasing the size difference between grains until these rapidly growing grains come into complete contact with each other.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"secondary recrystallization\"进行定义和解释，需要文字论述，答案也是详细的文字解释，符合简答题的特征。 | 知识层次: 题目考查对二次再结晶这一基本概念的定义和解释，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生理解并记忆\"二次再结晶\"的定义及其在晶粒生长中的分类（异常生长或不连续生长）。虽然涉及多个概念（正常生长、异常生长、二次再结晶），但主要是对基础概念的定义和描述，不需要进行复杂的比较分析或推导。因此，在选择题型中属于概念解释和描述层次的难度。", "convertible": true, "correct_option": "The abnormal growth of grains is also called discontinuous growth or secondary recrystallization.", "choice_question": "Which of the following is called secondary recrystallization?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting the correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The abnormal growth of grains in a polycrystalline material after primary recrystallization is complete", "B": "The nucleation and growth of new strain-free grains to replace deformed grains during annealing", "C": "The repeated occurrence of primary recrystallization in severely deformed materials", "D": "The simultaneous recrystallization of multiple phases in a composite material" }, "correct_answer": "A", "explanation": "The correct answer is A because secondary recrystallization specifically refers to the abnormal growth of a few grains after primary recrystallization is complete. Option B describes primary recrystallization, which is a common confusion point. Option C is a fabricated concept that sounds plausible but doesn't exist. Option D describes a completely different phenomenon in multiphase materials, exploiting the AI's potential to conflate related concepts.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3397, "question": "Why can't Cr12MoV steel be turned into stainless steel through heat treatment?", "answer": "Because Cr is the main factor that makes steel corrosion-resistant. It can increase the electrode potential of the steel. If its mass fraction is small (below 13 %), the electrode potential cannot be significantly increased, nor can a single-phase structure be formed, so the corrosion resistance of the steel cannot be significantly improved.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么Cr12MoV钢不能通过热处理变成不锈钢，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求解释Cr12MoV钢不能通过热处理转变为不锈钢的原因，涉及Cr元素对钢的耐腐蚀性能的影响机制，包括电极电位的变化和单相结构的形成条件。这需要综合运用材料科学中的合金元素作用原理、热处理对组织性能的影响以及腐蚀机制等多方面知识，进行推理分析和机理解释。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "Because Cr is the main factor that makes steel corrosion-resistant. It can increase the electrode potential of the steel. If its mass fraction is small (below 13 %), the electrode potential cannot be significantly increased, nor can a single-phase structure be formed, so the corrosion resistance of the steel cannot be significantly improved.", "choice_question": "Why can't Cr12MoV steel be turned into stainless steel through heat treatment?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because Cr is the main factor that makes steel corrosion-resistant. It can increase the electrode potential of the steel. If its mass fraction is small (below 13 %), the electrode potential cannot be significantly increased, nor can a single-phase structure be formed, so the corrosion resistance of the steel cannot be significantly improved.", "B": "Because the Mo content in Cr12MoV forms stable carbides that prevent chromium from diffusing to form a passive layer, making heat treatment ineffective for improving corrosion resistance.", "C": "Because the V element in Cr12MoV preferentially reacts with oxygen during heat treatment, consuming the oxygen needed for passive film formation on chromium.", "D": "Because the carbon content in Cr12MoV is too high, which leads to excessive carbide precipitation during heat treatment, reducing the effective chromium content available for corrosion resistance." }, "correct_answer": "A", "explanation": "The correct answer is A because chromium content below 13% cannot form the necessary passive film for stainless properties. Option B is a cognitive bias trap - while Mo does form carbides, this isn't the primary reason. Option C exploits professional intuition about V's reactivity but misapplies it. Option D is a multi-level trap combining true facts (carbon content) with incorrect conclusions about heat treatment effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1828, "question": "One of the conditions for the peptization of clay slurry is (7)", "answer": "Exchange of original cations with monovalent alkali metal cations", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释粘土浆体胶溶的条件之一，答案是一个具体的解释性陈述，而不是从多个选项中选择或判断对错，也不需要数值计算。 | 知识层次: 题目考查粘土浆料胶溶作用的基本条件，属于基本原理的记忆性知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆，但需要考生理解粘土浆体胶溶的条件之一，即原始阳离子与单价碱金属阳离子的交换。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。", "convertible": true, "correct_option": "Exchange of original cations with monovalent alkali metal cations", "choice_question": "One of the conditions for the peptization of clay slurry is:", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Exchange of original cations with monovalent alkali metal cations", "B": "Presence of divalent cations to enhance particle bridging", "C": "Maintaining pH below 4 to prevent colloidal stability", "D": "Addition of polyvalent anions to neutralize surface charges" }, "correct_answer": "A", "explanation": "The correct answer is A because peptization requires replacing the original cations (usually Ca2+ or Mg2+) with monovalent cations (like Na+) to reduce attractive forces between particles. Option B is a cognitive bias trap - while divalent cations are important in flocculation, they hinder peptization. Option C exploits pH confusion - low pH actually promotes flocculation, not peptization. Option D is a multi-level trap - while charge neutralization is important, polyvalent anions would cause flocculation, not the desired peptization effect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4884, "question": "Estimate the maximum thermal conductivity value for a cermet that contains 90 vol% titanium carbide (TiC) particles in a nickel matrix. Assume thermal conductivities of 27 and 67 W/m·K for TiC and Ni, respectively.", "answer": "the maximum thermal conductivity k_max is 31.0 W/m·K.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来估计cermet的最大热导率值，答案是一个具体的数值结果（31.0 W/m·K），这表明解答过程涉及计算步骤。 | 知识层次: 题目需要应用复合材料热导率的计算公式，涉及多步计算和不同材料性能的综合分析，但不需要复杂的推理或创新设计。 | 难度: 在选择题中属于中等难度，需要理解复合材料热导率的概念，掌握混合规则（如串联模型），并进行多步计算。虽然题目给出了具体数值，但需要正确应用公式和逻辑推理才能得出正确答案。", "convertible": true, "correct_option": "31.0 W/m·K", "choice_question": "Estimate the maximum thermal conductivity value for a cermet that contains 90 vol% titanium carbide (TiC) particles in a nickel matrix. Assume thermal conductivities of 27 and 67 W/m·K for TiC and Ni, respectively. The maximum thermal conductivity is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "31.0 W/m·K", "B": "58.2 W/m·K", "C": "27.6 W/m·K", "D": "64.3 W/m·K" }, "correct_answer": "A", "explanation": "正确答案A(31.0 W/m·K)是通过并联模型计算得出的最大值，即k_max = V_TiC*k_TiC + V_Ni*k_Ni = 0.9*27 + 0.1*67 = 31.0。干扰项B(58.2 W/m·K)利用了串联模型计算，这是最小值而非最大值，专门针对会混淆两种边界条件的AI。干扰项C(27.6 W/m·K)接近TiC的值，针对可能忽略金属基体贡献的AI。干扰项D(64.3 W/m·K)接近纯Ni的值，针对可能错误认为高导热相主导的AI。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2644, "question": "There is a copolymer ABS (A—acrylonitrile, B—butadiene, S—styrene), with the same mass fraction for each monomer. Calculate the mole fraction of each monomer.", "answer": "Acrylonitrile (—C2H3CN—) monomer has a relative molecular mass of 53; butadiene (—C2H3C2H3—) monomer has a relative molecular mass of 54; styrene (—C2H3C6H5—) monomer has a relative molecular mass of 104. Assuming each weighs 1 g, then acrylonitrile has 1/53 mol, butadiene has 1/54 mol, and styrene has 1/104 mol. Therefore, the mole fractions of the monomers are: x_acrylonitrile = (1/53) / (1/53 + 1/54 + 1/104) = 40.1%; x_butadiene = (1/54) / (1/53 + 1/54 + 1/104) = 39.4%; x_styrene = (1/104) / (1/53 + 1/54 + 1/104) = 20.5%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求计算每个单体的摩尔分数，涉及数值计算和公式应用，答案给出了具体的计算过程和结果。 | 知识层次: 题目涉及基本的摩尔分数计算，需要应用相对分子质量和简单的数学运算，属于直接套用公式和基本计算的范畴，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要计算三个单体的摩尔分数，但每个步骤都是直接套用基本公式（摩尔分数定义），且计算过程较为直接。题目提供了所有必要的相对分子质量数据，避免了额外的查找或推导步骤。因此，在选择题型内属于等级2难度，比单一公式直接计算稍复杂，但不需要多个公式的组合或深入的概念分析。", "convertible": true, "correct_option": "Acrylonitrile: 40.1%, Butadiene: 39.4%, Styrene: 20.5%", "choice_question": "In a copolymer ABS with equal mass fractions for each monomer (acrylonitrile, butadiene, styrene), what are the mole fractions of each monomer?", "conversion_reason": "The calculation leads to a specific set of mole fractions, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Acrylonitrile: 40.1%, Butadiene: 39.4%, Styrene: 20.5%", "B": "Acrylonitrile: 33.3%, Butadiene: 33.3%, Styrene: 33.3%", "C": "Acrylonitrile: 25.0%, Butadiene: 50.0%, Styrene: 25.0%", "D": "Acrylonitrile: 39.4%, Butadiene: 40.1%, Styrene: 20.5%" }, "correct_answer": "A", "explanation": "The correct answer requires calculating mole fractions from mass fractions using the molecular weights of each monomer (acrylonitrile: 53.06 g/mol, butadiene: 54.09 g/mol, styrene: 104.15 g/mol). Option B is a cognitive bias trap that assumes equal mass fractions lead to equal mole fractions. Option C exploits confusion between mass and mole fractions by doubling butadiene's value. Option D swaps the values of acrylonitrile and butadiene to catch unit conversion errors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2373, "question": "According to the $FE=Fe=C$ phase diagram, calculate the percentage of cementite precipitated from all primary phases relative to the total system (the entire system) for an iron-carbon alloy with a carbon mass fraction of $3.6$ at the eutectoid temperature.", "answer": "For an alloy with a carbon mass fraction of $3.6$ just after solidification, the relative amount of all phases (including primary phases and phases in the eutectic) is: $$ A^{\\\\Psi}=\\\\frac{6.67-3.6}{6.67-2.14}=67.77\\\\%$$ During the cooling process, the relative amount of $Fe_3C$ precipitated from the primary phases relative to the total system is: $$ A^{tFe_3C}=67.77\\\\% \\\\times 23.35\\\\%=15.82\\\\%$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算，应用相图和相关公式来求解渗碳体的百分比，答案也给出了具体的计算过程和结果。 | 知识层次: 题目涉及多步计算和相图分析，需要理解铁碳相图的基本原理，并应用杠杆定律进行两次计算（先计算初生相比例，再计算其中渗碳体析出比例），属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图的基本概念，掌握杠杆定律的应用，并能进行多步计算。题目要求计算从所有初生相中析出的渗碳体相对于整个系统的百分比，涉及多个步骤和概念的综合运用，但相比复杂多变量计算问题，其难度略低。", "convertible": true, "correct_option": "15.82%", "choice_question": "According to the $FE=Fe=C$ phase diagram, what is the percentage of cementite precipitated from all primary phases relative to the total system for an iron-carbon alloy with a carbon mass fraction of $3.6$ at the eutectoid temperature?", "conversion_reason": "The calculation yields a specific numerical answer (15.82%), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "15.82%", "B": "22.36%", "C": "12.48%", "D": "18.94%" }, "correct_answer": "A", "explanation": "The correct answer is A (15.82%) as calculated using the lever rule on the Fe-C phase diagram for a 3.6% C alloy at the eutectoid temperature. Option B (22.36%) is a cognitive bias trap that incorrectly uses the total cementite percentage including both primary and eutectoid cementite. Option C (12.48%) is a professional intuition trap that miscalculates by using the wrong phase boundary compositions. Option D (18.94%) is a multi-level verification trap that appears plausible by averaging common cementite percentages but fails to account for the specific alloy composition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3304, "question": "Compare the distribution of alloying elements in bainitic transformation, pearlitic transformation, and martensitic transformation", "answer": "In pearlitic transformation, alloying elements are redistributed through diffusion, while in bainitic transformation and martensitic transformation, alloying elements do not diffuse.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求对不同相变过程中合金元素的分布进行比较和解释，答案提供了详细的文字论述，符合简答题的特征。 | 知识层次: 题目要求比较三种相变过程中合金元素的分布情况，涉及多个概念（扩散、相变类型）的关联和综合分析，需要理解不同相变过程的机制及其对合金元素分布的影响，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求比较三种不同相变过程中合金元素的分布情况，涉及扩散和非扩散机制的理解。虽然不需要多步计算，但需要对珠光体相变、贝氏体相变和马氏体相变的基本原理有清晰认识，并能综合分析不同相变过程中合金元素的行为差异。这属于中等应用层次的知识要求，符合等级3的综合分析和说明标准。", "convertible": true, "correct_option": "In pearlitic transformation, alloying elements are redistributed through diffusion, while in bainitic transformation and martensitic transformation, alloying elements do not diffuse.", "choice_question": "Which of the following correctly describes the distribution of alloying elements in bainitic transformation, pearlitic transformation, and martensitic transformation?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct description among possible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In pearlitic transformation, alloying elements are redistributed through diffusion, while in bainitic transformation and martensitic transformation, alloying elements do not diffuse", "B": "All three transformations involve complete diffusion of alloying elements to achieve equilibrium composition", "C": "Only martensitic transformation shows complete solute trapping with no diffusion, while pearlite and bainite both involve partial diffusion", "D": "Bainitic transformation exhibits the most extensive alloy element redistribution due to its intermediate transformation temperature" }, "correct_answer": "A", "explanation": "The correct answer is A because pearlite forms by eutectoid decomposition which requires diffusion of alloying elements, while bainite and martensite form by shear mechanisms without time for diffusion. Option B is incorrect because it ignores the diffusionless nature of martensite. Option C is a subtle trap because while it correctly describes martensite, it incorrectly suggests partial diffusion in bainite. Option D exploits the common misconception that intermediate transformation temperatures necessarily mean intermediate diffusion behavior.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2167, "question": "Calculate the Burgers vector b of α-Fe, given the lattice constant of α-Fe a=0.28nm", "answer": "b=√3/2a=√3/2×0.28=0.25nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算Burgers vector b），并给出了具体的公式应用（b=√3/2a），最终答案是一个具体的数值结果（0.25nm）。这符合计算题的特征。 | 知识层次: 题目仅需应用已知公式（Burgers vector计算公式）进行一步数值计算，无需多步推理或综合分析，属于基本公式的直接套用。 | 难度: 在选择题型中，该题目仅需要直接套用已知公式（Burgers vector计算公式）并进行简单数值计算。题目没有涉及多个公式的组合或复杂推导，属于单一公式直接计算的类型，因此难度等级为1。", "convertible": true, "correct_option": "0.25nm", "choice_question": "Calculate the Burgers vector b of α-Fe, given the lattice constant of α-Fe a=0.28nm:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.25nm", "B": "0.28nm", "C": "0.20nm", "D": "0.14nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.25nm) because the Burgers vector for α-Fe (BCC structure) is calculated as (a√3)/2, where a=0.28nm. Option B (0.28nm) exploits the cognitive bias of directly using the lattice constant without proper calculation. Option C (0.20nm) is designed based on incorrect intuition about FCC structures. Option D (0.14nm) traps those who mistakenly use a/2 without considering the BCC slip system geometry.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3880, "question": "What is the quenching temperature required to produce a quenched and tempered eutectoid steel with a HRC hardness of less than 50?", "answer": "Quench to below the M_gamma (less than 130 degrees Celsius).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释淬火温度的具体要求，答案需要文字说明而非选择、判断或计算。 | 知识层次: 题目需要理解淬火温度与钢的硬度和组织转变之间的关系，涉及多步概念关联和综合分析，如M_gamma温度的概念、淬火工艺对硬度的影响等，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及淬火温度、马氏体转变温度（M_gamma）以及硬度要求等概念的综合应用，解题时需要将这些知识点关联起来，并理解它们之间的相互作用。虽然题目提供了明确的正确选项，但需要一定的背景知识才能准确判断。", "convertible": true, "correct_option": "Quench to below the M_gamma (less than 130 degrees Celsius)", "choice_question": "What is the quenching temperature required to produce a quenched and tempered eutectoid steel with a HRC hardness of less than 50?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Quench to below the M_gamma (less than 130 degrees Celsius)", "B": "Quench to between 300-400 degrees Celsius to form lower bainite", "C": "Quench to room temperature (25 degrees Celsius) followed by tempering", "D": "Quench to just above the A1 temperature (727 degrees Celsius)" }, "correct_answer": "A", "explanation": "The correct answer is A because quenching below the M_gamma temperature (martensite start temperature) for eutectoid steel ensures minimal martensite formation, which when tempered will result in HRC hardness below 50. Option B is incorrect because lower bainite formation would still result in higher hardness. Option C is a common misconception - full quenching to room temperature would produce too much martensite, making it impossible to achieve HRC<50 even after tempering. Option D exploits confusion with annealing temperatures, but quenching above A1 would not produce the desired microstructure.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1564, "question": "Based on the relationship between dislocation motion and crystal slip, analyze the relationship between the Burgers vector of a pure edge dislocation and the direction of dislocation line motion", "answer": "The Burgers vector is parallel to the direction of dislocation line motion", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求分析位错运动与晶体滑移之间的关系，并解释纯刃位错的Burgers矢量与位错线运动方向的关系。这需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求分析刃位错的Burgers矢量与位错线运动方向之间的关系，这需要理解位错运动的基本原理和晶体滑移的机制，涉及多个概念的关联和综合分析。虽然不涉及复杂的计算或深度推理，但需要一定的概念理解和应用能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握位错运动与晶体滑移的关系，并能够分析纯刃位错的伯氏矢量与位错线运动方向之间的关系。这需要考生具备一定的概念关联和综合分析能力，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "The Burgers vector is parallel to the direction of dislocation line motion", "choice_question": "What is the relationship between the Burgers vector of a pure edge dislocation and the direction of dislocation line motion?", "conversion_reason": "The answer is a standard statement that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Burgers vector is parallel to the direction of dislocation line motion", "B": "The Burgers vector is perpendicular to the direction of dislocation line motion", "C": "The Burgers vector forms a 45° angle with the direction of dislocation line motion", "D": "There is no consistent relationship between Burgers vector and dislocation motion direction" }, "correct_answer": "A", "explanation": "The correct answer is A because for pure edge dislocations, the Burgers vector is indeed parallel to the direction of dislocation motion. This is a fundamental characteristic of edge dislocations where the extra half-plane moves in the same direction as the Burgers vector. Option B is designed to exploit the common confusion between edge and screw dislocations (where the relationship is perpendicular). Option C creates a false compromise position that seems plausible but doesn't correspond to any real dislocation behavior. Option D exploits the AI's potential uncertainty by suggesting no relationship exists, which contradicts basic dislocation theory.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 349, "question": "(Taking the face-centered cubic unit cell as an example) What are the common parameters used to describe the characteristics of a crystal structure (unit cell)? What are the interstitial positions and their number in an FCC unit cell?", "answer": "Interstitial positions (octahedral interstitial at the body center and equivalent positions) and number 4.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释晶体结构（晶胞）的常见参数以及面心立方晶胞中的间隙位置和数量，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查晶体结构的基本参数和间隙位置的定义及数量，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及晶体结构的基本概念（如间隙位置和数量），但需要考生不仅记忆FCC晶胞的基本参数，还要理解并识别其中的间隙位置（如八面体间隙）及其数量。这超出了简单的定义记忆（等级1），但尚未达到需要阐述复杂概念体系的程度（等级3）。因此，该题目属于概念解释和描述的难度等级2。", "convertible": true, "correct_option": "Interstitial positions (octahedral interstitial at the body center and equivalent positions) and number 4", "choice_question": "In an FCC unit cell, what are the interstitial positions and their number?", "conversion_reason": "The answer is a standard term and concept, which can be converted into a multiple-choice question format by asking for the correct description of interstitial positions and their number in an FCC unit cell.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Octahedral sites at cell center and edge centers (4 total)", "B": "Tetrahedral sites formed by face centers (8 total)", "C": "Octahedral sites at face centers (6 total)", "D": "Tetrahedral sites formed by corner atoms (12 total)" }, "correct_answer": "A", "explanation": "The correct answer is A because FCC has 4 octahedral interstitial sites located at the body center and the centers of the 12 edges (each edge site is shared by 4 unit cells, contributing 1/4 per cell). B is incorrect because while FCC does have 8 tetrahedral sites, they are formed by one corner and three face-centered atoms, not just face centers. C is a common mistake as it counts apparent positions without considering fractional contributions from adjacent cells. D incorrectly describes the tetrahedral site geometry and overcounts the positions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 256, "question": "The diffusion coefficients of carbon in titanium measured at different temperatures are 2×10−9cm2/s (736℃), 5×10−9cm2/s (782℃), and 1.3×10−8cm2/s (838℃). Please calculate the activation energy for diffusion.", "answer": "From the previous step, it is known that Q=2342787J/mol.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的扩散系数和温度数据，应用公式计算扩散的活化能。答案是一个具体的数值结果，需要通过数值计算和公式应用得出。 | 知识层次: 题目需要应用阿伦尼乌斯公式进行多步计算，涉及对数运算和线性回归分析，属于中等应用层次。虽然计算过程较为直接，但需要理解扩散系数与温度的关系，并进行数据处理和公式转换。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散系数与温度的关系（阿伦尼乌斯方程），进行多步对数计算和斜率求解，最后转换为激活能量。虽然选择题提供了正确选项，但仍需完成完整的计算流程才能验证答案的正确性，涉及中等应用层次的知识综合运用能力。", "convertible": true, "correct_option": "2342787J/mol", "choice_question": "The diffusion coefficients of carbon in titanium measured at different temperatures are 2×10−9cm2/s (736℃), 5×10−9cm2/s (782℃), and 1.3×10−8cm2/s (838℃). The activation energy for diffusion is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2342787 J/mol", "B": "189.5 kJ/mol", "C": "2.34×10^6 J/mol", "D": "152.3 kJ/mol" }, "correct_answer": "A", "explanation": "The correct answer A is obtained by applying the Arrhenius equation to the given diffusion coefficients and temperatures. Option B is a cognitive bias trap that uses the correct magnitude but wrong units (kJ instead of J). Option C is a professional intuition trap that appears numerically close but results from incorrect logarithmic calculations. Option D is a multi-level verification trap that seems plausible for interstitial diffusion but is actually for a different material system.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3655, "question": "We replace 7.5 atomic percent of the chromium atoms in its BCC crystal with tantalum. X-ray diffraction shows that the lattice parameter is 0.29158nm. Calculate the density of the alloy.", "answer": "8.265g / {cm}^{3}", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解合金的密度，答案是一个具体的数值结果（8.265g/cm³），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括原子百分比替换、晶格参数的应用以及密度的计算，涉及概念关联和综合分析。虽然不涉及复杂的推理分析或机理解释，但需要一定的思维深度和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解合金成分替换的概念、BCC晶体结构参数与密度的关系，并进行多步计算（包括原子质量换算、晶胞体积计算和密度公式应用）。虽然题目提供了关键参数（晶格常数），但仍需要综合运用材料科学和化学知识才能得出正确答案。", "convertible": true, "correct_option": "8.265g/cm³", "choice_question": "We replace 7.5 atomic percent of the chromium atoms in its BCC crystal with tantalum. X-ray diffraction shows that the lattice parameter is 0.29158nm. The density of the alloy is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.265 g/cm³", "B": "7.892 g/cm³", "C": "8.419 g/cm³", "D": "7.314 g/cm³" }, "correct_answer": "A", "explanation": { "correct": "The correct density calculation considers the weighted average of atomic masses (Cr: 51.996, Ta: 180.948) and the BCC unit cell volume. With 7.5% Ta substitution, the average atomic mass is 57.246 g/mol. The BCC unit cell contains 2 atoms, giving a density of 8.265 g/cm³.", "distractors": { "B": "This value results from incorrectly assuming FCC structure (4 atoms/unit cell) while keeping correct mass calculation, exploiting crystal structure confusion.", "C": "This comes from using pure Ta density (16.654 g/cm³) scaled by atomic percentage, creating a tempting but physically invalid linear interpolation.", "D": "This mimics the density of pure chromium (7.19 g/cm³) with slight modification, playing on the expectation that alloying won't drastically change density." } }, "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 82, "question": "Explain the meaning of the symbol (V_{Na}'V_{Cl}^*)", "answer": "An associated center formed by the nearest Na vacancy and Cl vacancy", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释符号的含义，需要用文字进行解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对材料科学中缺陷符号的基本概念的记忆和理解，属于定义性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并解释一个特定的符号含义（V_{Na}'V_{Cl}^*），这比单纯记忆定义或分类稍复杂。正确选项要求考生能够将符号与具体的物理概念（即由最近的Na空位和Cl空位形成的关联中心）联系起来，这需要一定的概念理解和描述能力，而不仅仅是简单的记忆。因此，该题目在选择题型中属于等级2难度。", "convertible": true, "correct_option": "An associated center formed by the nearest Na vacancy and Cl vacancy", "choice_question": "What is the meaning of the symbol (V_{Na}'V_{Cl}^*)?", "conversion_reason": "The answer is a standard term or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "An associated center formed by the nearest Na vacancy and Cl vacancy", "B": "A Frenkel defect pair in NaCl crystal", "C": "A Schottky defect where V_Na' represents cation vacancy and V_Cl^* represents anion interstitial", "D": "A charged vacancy complex where V_Na' is a negatively charged Na vacancy and V_Cl^* is a positively charged Cl vacancy" }, "correct_answer": "A", "explanation": "The correct answer is A because the notation (V_{Na}'V_{Cl}^*) specifically denotes an associated center formed by the nearest neighbor Na vacancy (V_{Na}') and Cl vacancy (V_{Cl}^*). Option B is incorrect because it describes a Frenkel defect (vacancy-interstitial pair), not a vacancy-vacancy association. Option C is a cognitive bias trap, mixing correct vacancy notation with incorrect defect type (Schottky defects involve vacancy pairs, not vacancy-interstitial). Option D is a professional intuition trap, correctly identifying charge states but misrepresenting the physical configuration as separate charged vacancies rather than an associated pair.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4273, "question": "For screw dislocation, cite the relationship between the direction of the applied shear stress and the direction of dislocation line motion.", "answer": "screw dislocation--perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释和论述螺丝位错中施加的剪切应力方向与位错线运动方向之间的关系，答案需要文字描述而非选择或判断。 | 知识层次: 题目考查对螺型位错基本概念的记忆和理解，即施加的剪切应力方向与位错线运动方向之间的关系，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆螺丝位错的基本定义和方向关系，属于基础概念记忆层次，解题步骤简单，无需复杂分析或推理。", "convertible": true, "correct_option": "perpendicular", "choice_question": "For screw dislocation, what is the relationship between the direction of the applied shear stress and the direction of dislocation line motion?", "conversion_reason": "The answer is a standard term (perpendicular) that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "perpendicular", "B": "parallel", "C": "45-degree angle", "D": "stress direction determines Burgers vector direction" }, "correct_answer": "A", "explanation": "For screw dislocations, the dislocation line motion direction is always perpendicular to the applied shear stress direction due to the nature of screw dislocation's Burgers vector being parallel to the dislocation line. Option B exploits the common confusion with edge dislocations where motion is parallel. Option C creates a false intuition about intermediate angles. Option D introduces a conceptual trap by suggesting stress can alter the fundamental Burgers vector orientation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4542, "question": "Which reaction occurs at the anode and which at the cathode?", "answer": "Oxidation occurs at the anode; reduction at the cathode.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释阳极和阴极发生的反应，需要用文字描述氧化和还原反应的位置，属于需要文字解释的简答题类型。 | 知识层次: 题目考查电化学中阳极和阴极反应的基本概念记忆，即氧化反应发生在阳极，还原反应发生在阴极。这是基础的定义性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即阳极和阴极上发生的反应类型（氧化和还原）。不需要复杂的推理或分析，只需直接回忆定义即可选择正确答案。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "Oxidation occurs at the anode; reduction at the cathode.", "choice_question": "Which of the following correctly describes the reactions at the anode and cathode?", "conversion_reason": "The answer is a standard terminology that can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Oxidation occurs at the anode; reduction at the cathode", "B": "Reduction occurs at the anode; oxidation at the cathode", "C": "Both oxidation and reduction occur at the anode", "D": "Both oxidation and reduction occur at the cathode" }, "correct_answer": "A", "explanation": "The correct answer is A because in electrochemical cells, oxidation always occurs at the anode (loss of electrons) and reduction at the cathode (gain of electrons). Option B reverses these processes, exploiting the common confusion between anode/cathode polarity. Option C and D are designed to trap systems that might conflate half-reactions with full redox processes, or misunderstand the fundamental separation of oxidation and reduction sites in electrochemical systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3340, "question": "There is a batch of approximately 10,000 pieces of 45 steel gears, which are subjected to relatively low contact stress but require good wear resistance on the teeth and minimal heat treatment deformation. What surface treatment should be selected for these parts? Why?", "answer": "High-frequency surface quenching. After high-frequency surface quenching, the surface hardness is 1-2 HRC higher than conventional quenching, providing good wear resistance. Additionally, since high-frequency surface quenching results in minimal heat treatment deformation, this process is selected.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述选择某种表面处理的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求根据具体工况（低接触应力、耐磨性要求、热处理变形小）选择合适的表面处理方法，并解释原因。这需要综合理解高频表面淬火的工艺特点（硬度提升、变形小）与材料性能（45钢）的关联，属于多因素综合分析的应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生综合考量材料特性（45钢）、应用场景（低接触应力但高耐磨需求）以及热处理工艺特性（高频表面淬火变形小且硬度更高），才能正确选择表面处理方法。这涉及多步概念关联和综合分析能力，但无需进行多角度或深度关联性分析，因此符合等级3的标准。", "convertible": true, "correct_option": "High-frequency surface quenching", "choice_question": "For a batch of approximately 10,000 pieces of 45 steel gears subjected to relatively low contact stress but requiring good wear resistance on the teeth and minimal heat treatment deformation, which surface treatment should be selected?", "conversion_reason": "The answer is a standard term (High-frequency surface quenching) and the question can be rephrased to fit a multiple-choice format by asking which surface treatment should be selected.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High-frequency surface quenching", "B": "Carburizing followed by quenching", "C": "Nitriding", "D": "Electroplating with hard chromium" }, "correct_answer": "A", "explanation": "High-frequency surface quenching is the correct choice because it provides localized hardening of the gear teeth with minimal distortion, suitable for low contact stress applications. Option B is a cognitive bias trap - carburizing creates excessive case depth and distortion for this requirement. Option C exploits professional intuition - nitriding provides excellent wear resistance but is unnecessarily expensive for this stress level. Option D is a multi-level verification trap - chromium plating seems plausible but lacks the required bonding strength for gear tooth applications.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1119, "question": "Why cannot the lever rule be used to analyze the relative amounts of phases in a vertical section of a ternary equilibrium phase diagram?", "answer": "The vertical section of a ternary equilibrium phase diagram is a pseudo-binary phase diagram, and the composition points of the equilibrium phases cannot be determined on this vertical section. Therefore, the lever rule cannot be used to calculate the relative amounts of phases on the vertical section of a ternary equilibrium phase diagram.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么杠杆定律不能用于分析三元平衡相图垂直截面中的相比例，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解三元平衡相图的垂直截面与伪二元相图的关系，并分析杠杆规则在此情境下的适用性限制。这涉及多步概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题型中，该题目属于较高难度，原因如下：", "convertible": true, "correct_option": "The vertical section of a ternary equilibrium phase diagram is a pseudo-binary phase diagram, and the composition points of the equilibrium phases cannot be determined on this vertical section. Therefore, the lever rule cannot be used to calculate the relative amounts of phases on the vertical section of a ternary equilibrium phase diagram.", "choice_question": "Why cannot the lever rule be used to analyze the relative amounts of phases in a vertical section of a ternary equilibrium phase diagram?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because the lever rule requires constant temperature conditions, which are violated in vertical sections", "B": "Because vertical sections represent non-equilibrium conditions where phase fractions are undefined", "C": "Because the composition points of equilibrium phases cannot be determined on a vertical section", "D": "Because ternary systems require three-dimensional lever calculations that cannot be projected onto 2D sections" }, "correct_answer": "C", "explanation": "The correct answer is C because vertical sections in ternary diagrams are pseudo-binary cuts where the actual tie lines (connecting equilibrium phases) don't lie within the plane of the section. Option A is wrong but tempting because it invokes a common temperature misconception. Option B exploits confusion between equilibrium and non-equilibrium diagrams. Option D sounds mathematically sophisticated but misrepresents the fundamental issue.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2556, "question": "If tension is applied along the [110] direction of an FCC crystal, please write down the possible activated slip systems.", "answer": "There are four possible activated slip systems, which are (111)[101], (111)[011], (111)[110], (111)[011].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求写出可能的激活滑移系统，需要文字解释和论述，而不是从选项中选择或判断对错。答案给出了具体的滑移系统，属于简答形式。 | 知识层次: 题目要求确定FCC晶体在特定方向受力时的滑移系统，需要理解晶体结构、滑移系统的基本概念，并能够将[110]方向与可能的滑移面进行关联分析。这涉及多步思考和概念的综合应用，但不需要复杂的推理或创新设计。 | 难度: 在选择题型中，该题目属于较高难度，因为它要求考生不仅掌握FCC晶体结构的基本知识，还需要理解滑移系统的概念，并能综合分析[110]方向施加张力时可能激活的滑移系统。解题步骤涉及多个概念的综合运用和计算，需要考生具备较强的综合分析能力和空间想象能力。", "convertible": true, "correct_option": "There are four possible activated slip systems, which are (111)[101], (111)[011], (111)[110], (111)[011].", "choice_question": "If tension is applied along the [110] direction of an FCC crystal, which of the following is the correct set of possible activated slip systems?", "conversion_reason": "The answer is a standard and specific set of slip systems, making it suitable for conversion into a multiple-choice question format where the correct answer can be clearly identified among distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(111)[101], (111)[011], (111)[110], (111)[011]", "B": "(111)[110], (111)[101], (111)[011], (111)[101]", "C": "(111)[110], (111)[101], (111)[011], (111)[110]", "D": "(111)[101], (111)[011], (111)[110], (111)[101]" }, "correct_answer": "A", "explanation": "The correct answer is A because in FCC crystals under tension along [110], the four possible slip systems must have the highest Schmid factor. Options B, C, and D contain duplicates or incorrect slip systems that do not satisfy the geometric conditions for activation. These options exploit the AI's tendency to overlook subtle differences in slip system indices and its difficulty in verifying uniqueness of solutions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2893, "question": "What is homoaddition polymerization?", "answer": "A polymerization reaction involving a single monomer is called homoaddition polymerization, abbreviated as homoaddition; the resulting polymer has the same composition as its monomer.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"homoaddition polymerization\"进行文字解释和论述，答案提供了详细的定义和说明，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即homoaddition polymerization的定义和基本特征，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目仅要求对基础定义进行简答，正确选项直接给出了homoaddition polymerization的定义和缩写形式，属于最基础的概念记忆层次。不需要任何解释或分析步骤，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "A polymerization reaction involving a single monomer is called homoaddition polymerization, abbreviated as homoaddition; the resulting polymer has the same composition as its monomer.", "choice_question": "Which of the following best describes homoaddition polymerization?", "conversion_reason": "The answer is a standard definition of a chemical term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A polymerization reaction involving a single monomer is called homoaddition polymerization, abbreviated as homoaddition; the resulting polymer has the same composition as its monomer.", "B": "A polymerization process where identical monomers add to a growing chain in alternating orientations, creating a stereoregular polymer structure.", "C": "A copolymerization technique where two chemically similar monomers are added sequentially to control polymer tacticity.", "D": "A chain-growth polymerization mechanism where monomers add to the active site without rearrangement, preserving the monomer's double bond character in the polymer backbone." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines homoaddition polymerization as involving a single monomer with composition preservation. Option B describes stereoregular polymerization, a common confusion due to the 'homo-' prefix suggesting uniformity. Option C introduces the concept of copolymerization, exploiting the tendency to associate 'homoaddition' with multiple monomers. Option D incorrectly incorporates chain-growth mechanism specifics, playing on the intuition that addition polymerization must involve double bond preservation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 982, "question": "What are the characteristics of the phase transformation products in the solid-state phase transformation of metals?", "answer": "There are metastable phases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释金属固态相变产物的特征，需要文字论述而非选择、判断或计算 | 知识层次: 题目考查对金属固态相变产物特征的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即金属固态相变产物的特征之一（亚稳相的存在）。题目不要求解释或比较多个概念，只需识别正确选项，属于最基础的定义简答难度。", "convertible": true, "correct_option": "There are metastable phases.", "choice_question": "What are the characteristics of the phase transformation products in the solid-state phase transformation of metals?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "There are metastable phases", "B": "The transformation follows classical nucleation theory exactly", "C": "The products always reach thermodynamic equilibrium", "D": "The transformation occurs through liquid phase intermediates" }, "correct_answer": "A", "explanation": "The correct answer is A because solid-state phase transformations often produce metastable phases due to kinetic constraints. Option B is a cognitive bias trap - while nucleation theory is important, real transformations often deviate from ideal theory. Option C exploits the common misconception that systems always reach equilibrium, ignoring kinetic barriers. Option D is a fundamental misdirection by suggesting liquid intermediates, which don't exist in solid-state transformations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 841, "question": "Indicate and explain the reverse transformation phenomenon in the characteristics of martensitic transformation", "answer": "When martensite is heated at a sufficiently rapid rate, it can directly transform back to the high-temperature phase without decomposition.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释马氏体转变中的逆转变现象，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释马氏体逆转变现象，这涉及到对马氏体相变机理的深入理解，需要综合运用相变动力学和热力学知识进行分析和解释，属于较高层次的认知要求。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "When martensite is heated at a sufficiently rapid rate, it can directly transform back to the high-temperature phase without decomposition.", "choice_question": "Which of the following describes the reverse transformation phenomenon in the characteristics of martensitic transformation?", "conversion_reason": "The answer is a standard explanation that can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "When martensite is heated at a sufficiently rapid rate, it can directly transform back to the high-temperature phase without decomposition", "B": "Martensite reverts to austenite through a two-stage process involving intermediate carbide precipitation", "C": "Reverse transformation occurs spontaneously at room temperature due to residual stress relaxation", "D": "The reverse transformation requires simultaneous application of pressure and temperature above A3" }, "correct_answer": "A", "explanation": "Correct answer A describes the unique characteristic of martensitic reverse transformation where rapid heating avoids diffusion-based decomposition. Option B exploits confusion with tempering processes, Option C uses an intuitive but incorrect stress-driven assumption, and Option D creates a complex multi-parameter trap by combining pressure effects from different transformation types.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 144, "question": "A borosilicate glass used for sealing lighting lamps has an annealing point of 544°C, a softening point of 780°C, and a viscous flow activation energy of 373.13 kJ/mol. Determine its working range.", "answer": "The working temperature range viscosity is generally 10^3~10^7 Pa·s. According to the formula T=ΔE/(R·ln(η/η0)): when η=10^3 Pa·s, T=1033.6K=760.6°C; when η=10^7 Pa·s, T=1038.9°C. Therefore, the working temperature range is 760.6°C~1038.9°C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的参数（退火点、软化点、粘流活化能）和公式计算玻璃的工作温度范围，答案是通过数值计算得出的具体温度区间，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及公式的应用和温度单位的转换，需要理解粘度和温度之间的关系，并进行综合分析以确定工作温度范围。虽然不涉及复杂的机理分析或创新设计，但比简单的直接套用公式更复杂。 | 难度: 在选择题中属于中等偏上难度，需要理解玻璃工作温度范围的概念，掌握粘度与温度的关系公式，并进行多步计算。虽然题目提供了必要的参数，但需要考生综合运用这些信息进行计算和分析，涉及中等应用层次的知识点。", "convertible": true, "correct_option": "760.6°C~1038.9°C", "choice_question": "A borosilicate glass used for sealing lighting lamps has an annealing point of 544°C, a softening point of 780°C, and a viscous flow activation energy of 373.13 kJ/mol. What is its working temperature range?", "conversion_reason": "The answer is a specific temperature range, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "760.6°C~1038.9°C", "B": "544°C~780°C", "C": "373°C~544°C", "D": "780°C~1120°C" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算粘性流动活化能和软化点得出的工作温度范围。干扰项B利用认知偏差，错误地将退火点和软化点直接作为工作范围；干扰项C通过单位混淆陷阱，将活化能数值错误转换为温度；干扰项D则基于专业直觉陷阱，看似符合高温玻璃特性但超出实际计算值。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4739, "question": "Consider the diffusion of some hypothetical metal Y into another hypothetical metal Z at 950^{\\circ} C; after 10h the concentration at the 0.5mm position (in metal Z) is 2.0 wt% Y. At what position will the concentration also be 2.0 wt% Y after a 17.5h heat treatment again at 950^{\\circ} C ? Assume preexponential and activation energy values of 4.3 × 10^{-4}{m}^{2} / s and 180,000 J/ mol, respectively, for this diffusion system.", "answer": "the position will be 0.66 mm.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及扩散方程和参数代入，最终得出具体数值结果。 | 知识层次: 题目需要进行多步计算，涉及扩散方程的公式应用和参数代入，需要理解扩散系数与时间和位置的关系，并进行综合分析。虽然不涉及复杂的机理解释或创新应用，但需要一定的概念关联和计算能力。 | 难度: 在选择题中属于中等偏上难度，需要理解扩散方程的应用并进行多步计算。题目涉及扩散系数的计算、时间与位置关系的综合分析，以及数学运算能力。虽然给出了正确选项，但解题过程需要较强的概念关联和计算能力。", "convertible": true, "correct_option": "0.66 mm", "choice_question": "Consider the diffusion of some hypothetical metal Y into another hypothetical metal Z at 950°C; after 10h the concentration at the 0.5mm position (in metal Z) is 2.0 wt% Y. At what position will the concentration also be 2.0 wt% Y after a 17.5h heat treatment again at 950°C? Assume preexponential and activation energy values of 4.3 × 10^{-4} m²/s and 180,000 J/mol, respectively, for this diffusion system.", "conversion_reason": "The question is a calculation problem with a definite numerical answer, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.66 mm", "B": "0.71 mm", "C": "0.59 mm", "D": "0.50 mm" }, "correct_answer": "A", "explanation": "正确答案A是通过正确应用扩散方程x ∝ √(Dt)计算得出，其中时间比例因子为√(17.5/10)=1.32，因此新位置为0.5mm×1.32=0.66mm。干扰项B(0.71mm)利用了线性时间比例的直觉错误(17.5/10=1.75×0.5)，干扰项C(0.59mm)错误地取了时间比例的倒数，干扰项D(0.50mm)则完全忽略了时间变化的影响。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2321, "question": "In a Kevlar fiber-epoxy resin composite, the fiber volume fraction is 0.3, the elastic modulus of the epoxy resin is 31 GPa, and the elastic modulus of the Kevlar fiber is 124 GPa. Calculate the modulus parallel to the fiber direction.", "answer": "The modulus in the fiber direction is 58.9 GPa. Calculation process: E_T=0.3×124+0.7×31=58.9 GPa.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解复合材料在纤维方向的模量，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目考查基本公式的直接应用和简单计算，仅需套用复合材料模量的混合法则公式进行计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式（混合法则）进行计算，无需复杂的分析或组合多个公式。解题步骤简单明了，属于最基础的难度等级。", "convertible": true, "correct_option": "58.9 GPa", "choice_question": "In a Kevlar fiber-epoxy resin composite, the fiber volume fraction is 0.3, the elastic modulus of the epoxy resin is 31 GPa, and the elastic modulus of the Kevlar fiber is 124 GPa. What is the modulus parallel to the fiber direction?", "conversion_reason": "The calculation yields a specific numerical answer (58.9 GPa), which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "58.9 GPa", "B": "93.1 GPa", "C": "46.5 GPa", "D": "124 GPa" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the rule of mixtures for longitudinal modulus: E_c = V_f*E_f + (1-V_f)*E_m = 0.3*124 + 0.7*31 = 58.9 GPa. Option B is the transverse modulus calculated incorrectly (using inverse rule of mixtures but forgetting to take reciprocal). Option C is the average of fiber and matrix moduli, a common oversimplification. Option D is the pure fiber modulus, tempting for those who ignore matrix contribution.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1923, "question": "Given a powder compact with an average particle size of 5μm, after sintering for 2 hours, the neck growth rate x/r=0.1. If grain growth is not considered, how much time is needed to sinter the compact to a neck growth rate x/r=0.2 via material transport by flow?", "answer": "The formula for material transport by flow: x/r = k r^(-1/2) t^(1/2). Substituting x/r=0.1, r=5μm, t=2h to solve for k: 0.1 = k (5)^(-1/2) (2)^(1/2), yielding k. Then substituting x/r=0.2, r=5μm, and k to solve for t: 0.2 = k (5)^(-1/2) t^(1/2), yielding t=8h. Material transport by flow requires 8h.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解所需时间，答案给出了具体的计算步骤和结果。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，需要将已知条件代入公式求解常数k，然后再用同样的公式求解新的时间t。整个过程不需要多步计算或复杂的概念关联，属于简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要代入公式并解方程，但整个过程仅涉及单一公式的直接套用和简单代数运算，不需要多个公式的组合或复杂推导。解题步骤清晰且直接，属于选择题型中较为基础的难度水平。", "convertible": true, "correct_option": "8h", "choice_question": "Given a powder compact with an average particle size of 5μm, after sintering for 2 hours, the neck growth rate x/r=0.1. If grain growth is not considered, how much time is needed to sinter the compact to a neck growth rate x/r=0.2 via material transport by flow?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format. The correct answer is derived from the given formula and conditions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8h", "B": "4h", "C": "2h", "D": "16h" }, "correct_answer": "A", "explanation": "The correct answer is A (8h) because neck growth rate (x/r) in viscous flow sintering follows a cubic relationship with time (x/r ∝ t^(1/3)). Doubling the neck growth rate from 0.1 to 0.2 requires 8 times the original time (2^3 = 8). Option B (4h) is a cognitive bias trap that assumes linear proportionality. Option C (2h) exploits the 'same time' intuition error. Option D (16h) is designed to catch those who mistakenly square instead of cube the time factor.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2395, "question": "If the resistance (shear stress) that dislocation slip needs to overcome is 9.8×10^5 Pa for copper, the shear modulus G of copper is 4×10^10 Pa, and the lattice constant is 0.55 nm. How thick is the low-dislocation-density layer on the surface of copper? It is known that copper has a face-centered cubic structure, and the Burgers vector length is 0.36/√2 nm = 0.255 nm.", "answer": "Due to the effect of the surface image force, dislocations near the surface are subjected to the image force F_im. When the image force is greater than or equal to the dislocation slip resistance, the dislocation slips out of the surface, reducing the dislocation density on the surface. Taking a screw dislocation as an example, the image force F_im per unit length parallel to the surface is F_im = τ_in b = G b^2 / (4π d), where d is the distance of the dislocation from the surface. When F_im equals the dislocation slip resistance, the corresponding d is the thickness of the low-dislocation-density layer on the surface. Therefore, d ≤ G b / (4π τ_⊥). The thickness of the low-dislocation-density layer for copper is d = (4×10^10 × 0.255×10^-9) / (4π × 9.8×10^5) m = 8.28×10^-7 m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解低位错密度层的厚度，答案中包含了具体的计算步骤和最终数值结果。 | 知识层次: 题目需要进行多步计算，涉及公式应用和概念关联（如表面镜像力、位错滑移阻力、剪切模量等），需要综合分析不同参数之间的关系，但不需要进行复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解表面镜像力、位错滑移阻力等概念，并进行多步计算（包括单位转换和公式代入）。虽然题目提供了关键公式，但需要考生正确关联概念并执行综合计算，属于典型的综合性计算问题。", "convertible": true, "correct_option": "8.28×10^-7 m", "choice_question": "If the resistance (shear stress) that dislocation slip needs to overcome is 9.8×10^5 Pa for copper, the shear modulus G of copper is 4×10^10 Pa, and the lattice constant is 0.55 nm. How thick is the low-dislocation-density layer on the surface of copper? It is known that copper has a face-centered cubic structure, and the Burgers vector length is 0.36/√2 nm = 0.255 nm.", "conversion_reason": "The calculation question has a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.28×10^-7 m", "B": "4.14×10^-7 m", "C": "1.24×10^-6 m", "D": "2.07×10^-7 m" }, "correct_answer": "A", "explanation": "正确答案A是通过τ=Gb/λ公式计算得出，其中τ=9.8×10^5 Pa, G=4×10^10 Pa, b=0.255 nm。干扰项B是正确答案的一半，利用了计算中可能遗漏的系数2的常见错误。干扰项C是正确答案的1.5倍，利用了剪切模量与弹性模量混淆的认知偏差。干扰项D是正确答案的1/4，基于对晶格常数与位错间距关系的错误直觉判断。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3068, "question": "What is traditionally referred to as 'ceramics'?", "answer": "Ordinary ceramics are inorganic polycrystalline solid materials obtained by processing natural silicate minerals (such as clay, feldspar, and quartz) through raw material processing—forming—sintering. Therefore, this type of ceramics is also called silicate ceramics.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对“ceramics”进行定义和解释，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查对传统陶瓷材料的基本定义和组成成分的记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项提供了较为详细的定义和分类信息，需要考生对\"ceramics\"的定义和组成材料有一定的理解和记忆。相比于仅要求简单定义的等级1题目，该题目要求考生掌握更具体的概念解释和描述，因此属于等级2难度。", "convertible": true, "correct_option": "Ordinary ceramics are inorganic polycrystalline solid materials obtained by processing natural silicate minerals (such as clay, feldspar, and quartz) through raw material processing—forming—sintering. Therefore, this type of ceramics is also called silicate ceramics.", "choice_question": "What is traditionally referred to as 'ceramics'?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Inorganic polycrystalline solids processed from natural silicate minerals via sintering", "B": "Any non-metallic solid material with covalent-ionic bonding", "C": "High-temperature processed materials with >50% crystalline phase content", "D": "Brittle materials with Vickers hardness >5 GPa and melting point >1500°C" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines traditional silicate ceramics. Option B exploits the bonding misconception by including all covalent-ionic solids. Option C traps those who overemphasize crystallinity thresholds. Option D uses plausible but overly restrictive mechanical property thresholds that exclude many traditional ceramics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2706, "question": "The density of $\\\\mathbf{M}_{\\\\mathbf{g}}\\\\mathbf{O}$ is $3.58\\\\:\\\\mathbf{g}/\\\\mathrm{cm}^{3}$, and its lattice constant is $0.42\\\\mathfrak{n m}$. Determine the number of Schottky defects per unit cell of $\\\\mathbf{M}_{\\\\mathbf{g}}\\\\mathrm{O}$.", "answer": "Let the number of Schottky defects per unit cell be x. $$ \\\\rho{=}\\\\frac{(4-x)\\\\times\\\\left[A_{\\\\mathrm{r}}(\\\\mathrm{M}g)+A_{\\\\mathrm{r}}(\\\\mathrm{O})\\\\right]}{a^{3}N_{\\\\mathrm{A}}}$$ $$ x=4-{\\\\frac{\\\\rho\\\\alpha^{3}N_{\\\\mathrm{{A}}}}{A_{\\\\mathrm{{r}}}(\\\\mathrm{Mg})+A_{\\\\mathrm{{r}}}(\\\\mathrm{O})}}=4-{\\\\frac{3.58\\\\times(4.2\\\\times10^{-8})^{3}\\\\times6.023\\\\times10^{23}}{24.31+16.00}}=0.0369$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定单位晶胞中的肖特基缺陷数量，答案给出了具体的计算过程和结果。 | 知识层次: 题目需要进行多步计算，包括密度公式的应用、单位转换、原子量的使用以及最终求解缺陷数量。虽然不涉及复杂的机理分析或创新设计，但需要综合运用多个概念和计算步骤，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解Schottky缺陷的概念，掌握密度计算公式，并能正确代入数据进行多步计算。题目涉及单位转换、摩尔质量应用和综合公式推导，但选项提供了明确的解题路径，减少了部分思考难度。", "convertible": true, "correct_option": "0.0369", "choice_question": "The density of $\\mathbf{M}_{\\mathbf{g}}\\mathbf{O}$ is $3.58\\:\\mathbf{g}/\\mathrm{cm}^{3}$, and its lattice constant is $0.42\\mathfrak{n m}$. Determine the number of Schottky defects per unit cell of $\\mathbf{M}_{\\mathbf{g}}\\mathrm{O}$.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0369", "B": "0.0421", "C": "0.0287", "D": "0.0523" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算MgO的晶格密度与实测密度的差异得出的Schottky缺陷浓度。干扰项B利用了常见晶格常数计算误差的认知偏差，将晶格常数错误地取为0.42nm的平方而非立方。干扰项C设计为基于NaCl结构的直觉陷阱，错误地假设了缺陷分布均匀性。干扰项D则是单位换算陷阱，错误地将密度单位从g/cm³直接转换为kg/m³进行计算。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4879, "question": "What is the process of compression molding used to form plastic materials?", "answer": "For compression molding, both heat and pressure are applied after the polymer and necessary additives are situated between the mold members.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释压缩成型的过程，答案提供了详细的文字描述，符合简答题的特征。 | 知识层次: 题目考查压缩成型过程的基本概念和原理，属于基础概念的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目仅考察对压缩成型工艺基本定义的记忆，属于最基础的概念性知识。正确选项直接描述了该工艺的核心要素（加热加压和模具位置），不需要任何解释或复杂推理过程，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "For compression molding, both heat and pressure are applied after the polymer and necessary additives are situated between the mold members.", "choice_question": "What is the process of compression molding used to form plastic materials?", "conversion_reason": "The answer is a standard description of the process, which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Applying heat and pressure to polymer placed between mold members", "B": "Injecting molten polymer into a closed mold under high pressure", "C": "Using only pressure to shape pre-heated polymer sheets", "D": "Extruding polymer through a die to create continuous profiles" }, "correct_answer": "A", "explanation": "Correct answer A precisely describes compression molding where both heat and pressure are applied to material placed between molds. B describes injection molding, a common confusion. C omits the critical heat application during molding. D describes extrusion process, exploiting surface similarity in polymer processing terms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2612, "question": "In the periodic table, how do the properties of elements change from left to right within the same period?", "answer": "From left to right, ionization energy increases, the ability to lose electrons decreases, the ability to gain electrons increases, metallic character weakens, and non-metallic character strengthens.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释元素周期表中同一周期内元素性质的变化趋势，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查元素周期表中同一周期内元素性质变化的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个元素性质的变化趋势（电离能、得失电子能力、金属性/非金属性），但这些都属于基础概念记忆范畴，且变化规律在周期表中呈现系统性。考生需要理解并记忆这些规律，但不需要进行复杂的推导或分析。相比等级1的简单定义题，该题需要整合多个相关概念；但相比等级3的复杂概念体系阐述题，其知识点的关联性和深度要求较低。", "convertible": true, "correct_option": "From left to right, ionization energy increases, the ability to lose electrons decreases, the ability to gain electrons increases, metallic character weakens, and non-metallic character strengthens.", "choice_question": "How do the properties of elements change from left to right within the same period in the periodic table?", "conversion_reason": "The answer is a standard description of periodic trends, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ionization energy decreases, metallic character strengthens", "B": "Electron affinity decreases, atomic radius increases", "C": "Electronegativity decreases, non-metallic character weakens", "D": "Ionization energy increases, metallic character weakens" }, "correct_answer": "D", "explanation": "The correct answer is D because ionization energy increases from left to right due to increasing nuclear charge, and metallic character weakens as elements become less likely to lose electrons. Option A reverses both trends, exploiting the common misconception that properties should show symmetrical patterns. Option B incorrectly states that electron affinity decreases (it actually increases) and atomic radius increases (it decreases), playing on the intuitive but wrong assumption that adding electrons would increase size. Option C reverses the trends for electronegativity and non-metallic character, which are key periodic trends that advanced AIs might misapply when considering exceptions to general patterns.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2743, "question": "Calculate the axial ratio c/a of an ideal close-packed hexagonal crystal structure", "answer": "c/a=√(8/3)=1.633", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算轴向比c/a），并给出了具体的计算公式和结果（c/a=√(8/3)=1.633），符合计算题的特征。 | 知识层次: 题目要求计算理想密排六方晶体结构的轴比c/a，涉及基本公式应用和简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用基本公式（c/a=√(8/3)）进行简单计算，无需额外的公式组合或复杂步骤，属于单一公式直接计算的难度等级。", "convertible": true, "correct_option": "c/a=√(8/3)=1.633", "choice_question": "What is the axial ratio c/a of an ideal close-packed hexagonal crystal structure?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.633", "B": "√2 ≈ 1.414", "C": "4/√3 ≈ 2.309", "D": "2π/3 ≈ 2.094" }, "correct_answer": "A", "explanation": "The correct answer is A (1.633) because the axial ratio c/a for an ideal close-packed hexagonal structure is derived from the geometric arrangement of spheres, yielding √(8/3). Option B (√2) exploits the common confusion with the face-centered cubic structure's planar packing ratio. Option C (4/√3) is designed to trap those who incorrectly apply the 2D hexagonal packing ratio. Option D (2π/3) leverages the false intuition that π might be involved in spherical packing calculations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2261, "question": "Describe the precipitation sequence of Al-Cu alloy", "answer": "The precipitation sequence of Al-Cu alloy is: GP zones → θ′′ metastable phase → θ′ metastable phase → θ phase (equilibrium phase)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求描述Al-Cu合金的析出序列，需要文字解释和论述，答案给出了详细的析出过程，符合简答题的特征。 | 知识层次: 题目考查Al-Cu合金的析出序列，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求描述Al-Cu合金的析出序列，但正确选项已经提供了完整的序列，学生只需记忆和理解这一序列即可。这涉及到基础概念的记忆和简单描述，不需要复杂的分析或比较。因此，在选择题型内，这属于等级2的难度。", "convertible": true, "correct_option": "GP zones → θ′′ metastable phase → θ′ metastable phase → θ phase (equilibrium phase)", "choice_question": "What is the precipitation sequence of Al-Cu alloy?", "conversion_reason": "The answer is a standard sequence of phases, which can be presented as a single correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "GP zones → θ′′ → θ′ → θ", "B": "GP zones → θ′ → θ′′ → θ", "C": "θ′′ → GP zones → θ′ → θ", "D": "θ′ → GP zones → θ′′ → θ" }, "correct_answer": "A", "explanation": "The correct sequence is GP zones → θ′′ → θ′ → θ. Option B reverses the order of θ′′ and θ′, exploiting the common confusion between these metastable phases. Option C starts with θ′′ instead of GP zones, targeting the misconception that larger precipitates form first. Option D begins with θ′, which is the most stable metastable phase, creating a false intuition that stability determines formation order.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 995, "question": "What is the difference between kinks and jogs produced when two dislocations intersect?", "answer": "The intersection of dislocations belongs to the interaction between dislocations, resulting in a bend on each other's dislocation line with a magnitude and direction equal to its Burgers vector. This bend is called a kink or a jog. A kink is the bend produced after intersection that lies on the original slip plane and does not affect the movement of the dislocation, making it easy to disappear. A jog is the bend that does not lie on the original slip plane and affects the slip of the dislocation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释kinks和jogs的区别，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对位错相互作用中kinks和jogs的基本定义和区别的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并区分kinks和jogs的定义、产生条件以及对位错运动的影响。这要求考生不仅记住定义，还需要能够解释和描述这两个概念的区别。题目没有涉及复杂的推理或多步骤的分析，因此不属于最高难度等级。", "convertible": true, "correct_option": "A kink is the bend produced after intersection that lies on the original slip plane and does not affect the movement of the dislocation, making it easy to disappear. A jog is the bend that does not lie on the original slip plane and affects the slip of the dislocation.", "choice_question": "What is the difference between kinks and jogs produced when two dislocations intersect?", "conversion_reason": "The answer is a standard explanation of the terms 'kink' and 'jog', which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Kinks are temporary deviations that remain in the slip plane, while jogs require climb motion to move", "B": "Both kinks and jogs are identical defects that form when dislocations cross-slip", "C": "Kinks are permanent defects that impede dislocation motion, while jogs are temporary and easily annihilated", "D": "Jogs lie within the original slip plane while kinks create out-of-plane segments" }, "correct_answer": "A", "explanation": "The correct answer A precisely distinguishes that kinks remain in the slip plane (temporary) while jogs require climb (permanent). B is wrong by equating fundamentally different defects. C reverses the key properties of kinks/jogs. D inverts their slip plane relationships - a classic inversion trap that exploits cognitive bias.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1361, "question": "At what temperature or temperature range is eutectic cementite formed through what reaction? And write the reaction equation.", "answer": "Eutectic cementite: 1148°C, eutectic reaction, L→(γ+Fe3C) eutectic.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释在什么温度或温度范围内通过什么反应形成共晶渗碳体，并写出反应方程式。答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目考查对共晶反应温度范围和反应方程的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目要求考生记忆并准确回答共晶渗碳体的形成温度、反应类型及反应方程式，这些都是基础概念记忆性知识，无需复杂推理或分析。正确选项直接提供了所有必要信息，考生只需识别并选择匹配的选项即可。", "convertible": true, "correct_option": "1148°C, eutectic reaction, L→(γ+Fe3C) eutectic", "choice_question": "At what temperature or temperature range is eutectic cementite formed and what is the reaction equation?", "conversion_reason": "The answer is a standard term and reaction equation, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1148°C, eutectic reaction: L→(γ+Fe3C)", "B": "727°C, eutectoid reaction: γ→(α+Fe3C)", "C": "1495°C, peritectic reaction: L+δ→γ", "D": "912°C, allotropic transformation: α→γ" }, "correct_answer": "A", "explanation": "The correct answer is A because eutectic cementite forms at 1148°C through the eutectic reaction where liquid transforms to austenite (γ) and cementite (Fe3C). Option B is a common confusion point as it describes the eutectoid reaction at 727°C, which is important but distinct. Option C uses a high temperature peritectic reaction to exploit temperature range confusion. Option D leverages the allotropic transformation temperature to create a plausible but irrelevant alternative.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1963, "question": "At room temperature, a sheet of iron (with a melting point of 1538°C) is bent back and forth. What phenomenon will occur as the bending continues? Why?", "answer": "According to T_recrystallization = (0.35–0.45)T_melting, the processing of Fe at room temperature is cold working. Therefore, as bending proceeds, the sheet undergoes work hardening, and continued deformation leads to fracture of the iron sheet.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释现象并论述原因，答案提供了详细的文字解释和理论依据，符合简答题的特征。 | 知识层次: 题目需要理解冷加工和再结晶温度的概念，并应用公式T_recrystallization = (0.35–0.45)T_melting进行计算和判断。同时，需要解释铁片在室温下弯曲时发生的加工硬化和最终断裂的现象，涉及多个概念的关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及冷加工、再结晶温度计算、加工硬化等概念的综合应用，要求考生能够将理论知识与实际现象关联起来，并进行多步推理。虽然题目提供了计算公式，但仍需考生具备一定的材料科学基础才能正确理解和应用这些概念。", "convertible": true, "correct_option": "work hardening, and continued deformation leads to fracture of the iron sheet", "choice_question": "At room temperature, a sheet of iron (with a melting point of 1538°C) is bent back and forth. What phenomenon will occur as the bending continues?", "conversion_reason": "The answer is a standard term (work hardening) and the explanation is concise, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Work hardening occurs initially, followed by fracture due to dislocation accumulation", "B": "Recrystallization occurs, leading to grain refinement and improved ductility", "C": "Phase transformation from α-Fe to γ-Fe occurs due to mechanical stress", "D": "The iron sheet will soften due to dynamic recovery at room temperature" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual phenomenon where plastic deformation causes dislocation entanglement (work hardening) and eventual fracture. B is incorrect because recrystallization requires elevated temperatures. C is wrong as stress-induced phase transformation in iron requires either high pressure or specific alloying. D is false because dynamic recovery in pure iron requires temperatures above 0.3Tm (≈460°C). The distractors exploit common misconceptions about temperature effects (B,D) and stress-induced transformations (C).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1190, "question": "What is the first type of temper brittleness?", "answer": "The brittleness that occurs during tempering between 250~400°C is called low-temperature temper brittleness, also known as the first type of temper brittleness. The first type of temper brittleness is irreversible temper brittleness, which is caused by the discontinuous thin-shell-like carbides precipitated along the interface of martensite laths or plates during martensite decomposition, reducing the fracture strength of grain boundaries and making them the path for crack propagation, thus leading to brittle fracture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释什么是第一种回火脆性，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查的是对第一类回火脆性的定义和基本机理的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但正确选项不仅需要考生知道第一类回火脆性的温度范围（250~400°C），还需要理解其不可逆性以及微观机制（碳化物析出导致晶界强度降低）。这比单纯记忆定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "The brittleness that occurs during tempering between 250~400°C is called low-temperature temper brittleness, also known as the first type of temper brittleness.", "choice_question": "Which of the following describes the first type of temper brittleness?", "conversion_reason": "The answer is a standard definition or concept, which can be rephrased into a multiple-choice format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The brittleness that occurs during tempering between 250~400°C is called low-temperature temper brittleness", "B": "The brittleness caused by prolonged exposure to temperatures above 500°C due to carbide precipitation", "C": "The embrittlement phenomenon occurring during cooling from austenitizing temperature due to phosphorus segregation", "D": "The loss of toughness resulting from tempering in the range of 450~550°C due to impurity element segregation" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the first type (low-temperature) temper brittleness occurring in the 250-400°C range. Option B describes secondary temper embrittlement (high-temperature). Option C describes quench embrittlement, not temper brittleness. Option D describes the second type of temper brittleness occurring at higher temperatures. The distractors exploit common confusions between different types of embrittlement and their temperature ranges.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 565, "question": "How to eliminate work hardening phenomenon", "answer": "Subsequent recrystallization treatment is adopted to eliminate work hardening phenomenon. (3 points)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释如何消除加工硬化现象，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对消除加工硬化现象的基本方法的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对基础概念的简单记忆，只需识别\"recrystallization treatment\"是消除加工硬化现象的正确方法即可。题目不涉及概念解释或复杂体系阐述，属于最基本的知识点回忆型题目。", "convertible": true, "correct_option": "Subsequent recrystallization treatment is adopted to eliminate work hardening phenomenon.", "choice_question": "How to eliminate work hardening phenomenon?", "conversion_reason": "The answer is a standard and specific method, which can be used as the correct option in a multiple-choice question format. The question can be presented as is, with the answer serving as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Subsequent recrystallization treatment", "B": "Immediate quenching in liquid nitrogen", "C": "Applying reverse stress equal to yield strength", "D": "Controlled oxidation at elevated temperatures" }, "correct_answer": "A", "explanation": "Recrystallization is the only method that actually eliminates dislocations causing work hardening. Option B exploits the misconception that rapid cooling can reset dislocation structure, while in reality it would lock in defects. Option C uses elastic deformation knowledge but incorrectly applies it to permanent dislocation networks. Option D leverages surface treatment logic that doesn't address bulk material defects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3104, "question": "Commonly used expansion materials are divided into three categories: (1), (2), (3).", "answer": "(1) Low expansion materials; (2) Controlled expansion materials; (3) High expansion materials", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写三类膨胀材料的名称，需要文字回答而非选择或判断 | 知识层次: 题目考查对膨胀材料分类的基本概念记忆，属于定义和分类的记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别常见的膨胀材料分类，属于基础概念记忆的简单题目。题目直接给出了三个分类的正确选项，不需要进行复杂的分析或推理，仅需基本的记忆能力即可回答。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Low expansion materials; Controlled expansion materials; High expansion materials", "choice_question": "Commonly used expansion materials are divided into which three categories?", "conversion_reason": "The answer is a standard list of categories, which can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Low expansion materials; Controlled expansion materials; High expansion materials", "B": "Isotropic expansion materials; Anisotropic expansion materials; Negative expansion materials", "C": "Linear expansion materials; Area expansion materials; Volume expansion materials", "D": "Thermal expansion materials; Hygroscopic expansion materials; Phase-change expansion materials" }, "correct_answer": "A", "explanation": "正确答案A是基于材料热膨胀系数的标准分类。干扰项B利用各向同/异性材料的专业直觉陷阱；干扰项C通过物理维度分类制造认知偏差；干扰项D则用膨胀机制的不同类型进行多层次验证陷阱。这三个干扰项都包含真实存在的材料科学概念，但在膨胀材料分类情境下不适用。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2338, "question": "Calculate the packing density of a crystal structure with a coordination number of 6 for a monoatomic substance", "answer": "When the coordination number of a monoatomic substance is 6, it forms a simple cubic structure, where the atomic radius r1=a1×7. The packing density η=(1×(4/3)πr3)/a3=(4πa3)/(3×8×a3)=0.523", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求计算晶体的堆积密度，涉及数值计算和公式应用，答案也给出了具体的计算过程和结果。 | 知识层次: 题目涉及基本的晶体结构知识（简单立方结构）和简单的数学计算（原子半径与晶格参数的关系、堆积密度的公式应用），属于直接套用公式和进行一步计算的简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解协调数为6对应的简单立方结构，并应用原子半径与晶格常数的关系，但整体解题步骤较为直接，仅涉及基本公式的套用和简单计算，无需多个公式的组合或复杂分析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "0.523", "choice_question": "What is the packing density of a crystal structure with a coordination number of 6 for a monoatomic substance?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.523", "B": "0.680", "C": "0.740", "D": "0.602" }, "correct_answer": "A", "explanation": "The correct answer is A (0.523) because this represents the packing density of a simple cubic structure with coordination number 6. Option B (0.680) is the packing density for body-centered cubic (BCC) which has coordination number 8, exploiting confusion between different crystal structures. Option C (0.740) is for face-centered cubic (FCC) or hexagonal close-packed (HCP) with coordination number 12, a common overestimation. Option D (0.602) mimics the packing density of diamond cubic structure, creating confusion with other low-coordination systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 91, "question": "Write the defect reaction equation for the formation of Frenkel defects (Ag entering interstitial sites) in AgI", "answer": "AgAg $V_{Ag}$ $+Ag_{i}$", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求写出缺陷反应方程式，需要文字解释和论述，答案形式为化学方程式而非选择、判断或计算 | 知识层次: 题目考查对Frenkel缺陷形成的基本概念和反应方程的记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求写出Frenkel缺陷的形成反应方程，属于基础概念记忆的范畴。题目直接给出了正确选项，不需要复杂的分析或推理，只需记住基本的缺陷反应方程即可。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "AgAg $V_{Ag}$ $+Ag_{i}$", "choice_question": "Which of the following is the defect reaction equation for the formation of Frenkel defects (Ag entering interstitial sites) in AgI?", "conversion_reason": "The answer is a standard and specific equation, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "AgAg ↔ VAg + Agi", "B": "AgAg ↔ VAg + Ii", "C": "AgAg + Ii ↔ VAg + AgI", "D": "AgAg + VI ↔ Agi + II" }, "correct_answer": "A", "explanation": "The correct answer is A because it accurately represents the Frenkel defect formation in AgI where a silver ion (Ag) leaves its lattice site to become an interstitial (Agi), creating a silver vacancy (VAg). Option B incorrectly shows iodine interstitial formation instead of silver. Option C introduces an incorrect stoichiometry by including AgI formation. Option D falsely implies simultaneous formation of iodine vacancies and interstitials, which is a different defect mechanism (Schottky defect). The key challenge is recognizing that Frenkel defects involve only cation (Ag) movement in this case, not anion (I) defects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 3, "correct_answers": 3, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3650, "question": "BCC lithium has a lattice parameter of 3.5089 × 10^-8 cm and contains one vacancy per 200 unit cells. Calculate the density of Li.", "answer": "0.532 g/cm³", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（如晶格参数、空位密度等）来求解锂的密度，答案是一个具体的数值结果（0.532 g/cm³），符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括计算单位晶胞的质量、考虑空位的影响，以及应用密度公式。这需要理解BCC结构的基本概念，并能将空位浓度与密度计算关联起来，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构、晶格参数与密度的关系，并进行多步计算。题目涉及单位换算、缺陷浓度对密度的影响等综合分析，但选项提供了明确答案，减少了部分复杂性。", "convertible": true, "correct_option": "0.532 g/cm³", "choice_question": "BCC lithium has a lattice parameter of 3.5089 × 10^-8 cm and contains one vacancy per 200 unit cells. The density of Li is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.532 g/cm³", "B": "0.541 g/cm³", "C": "0.515 g/cm³", "D": "0.508 g/cm³" }, "correct_answer": "A", "explanation": "正确答案A考虑了空位缺陷对密度的实际影响。干扰项B忽略了空位缺陷，直接计算理想BCC结构密度。干扰项C错误地将空位浓度放大100倍计算。干扰项D则错误地使用了FCC结构的堆积因子进行计算。这些干扰项分别利用了：B-忽略缺陷的直觉陷阱；C-数量级放大的认知偏差；D-晶体结构混淆的专业直觉陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2106, "question": "Point out the error in the following concept and correct it: In the directional solidification process of a solid solution alloy rod, the faster the liquid-solid interface advances, the more severe the macrosegregation in the rod.", "answer": "the less severe the macrosegregation in the rod.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求指出并纠正一个概念错误，类似于判断陈述的对错并给出正确表述。答案形式是直接纠正错误陈述，不需要计算或详细论述。 | 知识层次: 题目涉及对定向凝固过程中宏观偏析现象的理解和应用，需要将凝固速率与偏析程度的关系进行综合分析，属于中等应用层次的知识点。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅要理解定向凝固过程的基本原理，还需要掌握宏观偏析的形成机制及其与凝固速率的关系。这需要考生能够综合分析多个概念（如溶质分配、扩散速率、界面稳定性等），并正确判断因果关系。虽然题目给出了正确选项，但判断过程涉及中等应用层次的知识关联和综合分析能力，比单纯的概念识别或单步计算更为复杂。", "convertible": true, "correct_option": "the less severe the macrosegregation in the rod.", "choice_question": "Point out the error in the following concept and correct it: In the directional solidification process of a solid solution alloy rod, the faster the liquid-solid interface advances, the more severe the macrosegregation in the rod.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all cases of directional solidification, increasing the solidification rate will decrease the degree of macrosegregation in the final product.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While faster solidification rates generally reduce macrosegregation by limiting solute diffusion time, this is not universally true. Under certain conditions (e.g., with specific alloy compositions or thermal gradients), increased solidification rates can actually promote segregation patterns. The absolute claim 'in all cases' makes this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 270, "question": "When measuring the decomposition rate of alumina monohydrate, it was found that during the isothermal reaction, the mass loss increased linearly with time up to about 50%, and the rate of mass loss was less than the linear law when exceeding 50%. The rate increases exponentially with temperature. Is this a diffusion-controlled reaction or an interface first-order reaction-controlled reaction?", "answer": "According to the analysis of the kinetic equations for some important solid-phase reactions in Table 8-2 and the G-t/t0.5 curves for various types of reactions in Figure 8-22, it is known from the problem statement that when G ≤ 50%, G-t shows a linear relationship, and when G > 50%, G-t is less than the linear law. This is a diffusion-controlled reaction, and G² = kt.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述反应类型（扩散控制反应或界面一级反应控制反应），答案提供了详细的分析和结论，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求分析实验数据并判断反应类型，需要综合运用动力学方程和反应机理知识，涉及多步推理和综合分析。不仅需要理解扩散控制和界面一级反应控制的区别，还需要根据G-t关系曲线进行判断，思维过程较为复杂。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "diffusion-controlled reaction", "choice_question": "When measuring the decomposition rate of alumina monohydrate, it was found that during the isothermal reaction, the mass loss increased linearly with time up to about 50%, and the rate of mass loss was less than the linear law when exceeding 50%. The rate increases exponentially with temperature. Is this a diffusion-controlled reaction or an interface first-order reaction-controlled reaction?", "conversion_reason": "The answer is a standard term (diffusion-controlled reaction), which can be directly used as a correct option in a multiple-choice question. The question can be presented as is, with the answer choices being 'diffusion-controlled reaction' and 'interface first-order reaction-controlled reaction'.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Diffusion-controlled reaction", "B": "Interface first-order reaction-controlled reaction", "C": "Mixed control mechanism with both diffusion and reaction components", "D": "Surface nucleation-controlled reaction" }, "correct_answer": "A", "explanation": "The correct answer is A because the initial linear mass loss followed by deviation from linearity at higher conversions is characteristic of diffusion-controlled reactions, where the rate becomes limited by product layer diffusion. The exponential temperature dependence also supports this. Option B is a strong distractor because the initial linear portion might intuitively suggest first-order kinetics. Option C exploits the common tendency to assume mixed mechanisms in complex reactions. Option D targets the misconception that surface nucleation must be involved in solid-state decompositions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3062, "question": "What material is suitable for steam turbine blades? Options: A.Polyvinyl chloride B.2Cr13 C.High-temperature ceramics D.Manganese brass", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择最适合蒸汽涡轮叶片的材料，答案形式为选项中的一个字母 | 知识层次: 题目考查对特定应用场景下材料选择的基本知识，需要理解不同材料的特性和适用环境，但不需要复杂的分析或综合推理。 | 难度: 在选择题中属于简单难度，题目直接考察对蒸汽轮机叶片材料的基本知识，只需识别2Cr13是适合的材料，无需复杂计算或多步骤推理。", "convertible": true, "correct_option": "B.2Cr13", "choice_question": "What material is suitable for steam turbine blades?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ti-6Al-4V with 0.2% oxygen content", "B": "2Cr13", "C": "Inconel 718 aged at 760°C for 10 hours", "D": "Single crystal CMSX-4 superalloy with [001] orientation" }, "correct_answer": "B", "explanation": "Correct answer is B (2Cr13) because it offers the optimal balance of high-temperature strength, corrosion resistance, and cost-effectiveness for steam turbine blades. A is incorrect (Ti-6Al-4V) - while titanium alloys have excellent strength-to-weight ratio, they become brittle at steam turbine operating temperatures due to oxygen embrittlement. C is incorrect (Inconel 718) - though excellent for jet engines, its precipitation hardening behavior makes it unsuitable for the thermal cycling conditions in steam turbines. D is incorrect (CMSX-4) - while single crystal superalloys have outstanding creep resistance, their extreme cost and anisotropic properties make them impractical for most steam turbine applications.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 685, "question": "The core of microscopic symmetry elements is the translation axis", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述句要求判断对错（√表示正确），符合判断题的特征 | 知识层次: 题目考查对微观对称元素核心概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，这道题目属于非常基础的正误判断题，仅需要考生记忆微观对称元素的核心概念（平移轴）即可做出正确判断。题目不涉及概念理解或复杂陈述的分析，完全符合等级1\"基本概念正误判断\"的标准。", "convertible": true, "correct_option": "√", "choice_question": "The core of microscopic symmetry elements is the translation axis", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials exhibit short-range order but completely lack any form of long-range order.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While amorphous materials do lack long-range translational symmetry, some may exhibit medium-range order (2-5nm scale) that goes beyond simple short-range order. Certain amorphous metals and oxide glasses can show this intermediate ordering, making the 'completely lack' statement too absolute.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4094, "question": "A stress-strain test is performed on an aligned fibrous composite such that the force is applied in the longitudinal direction. During the initial stage of the test, which phase bears most of the load?(a) Fibers(b) Matrix", "answer": "During a stress-strain test that is performed on an aligned fibrous composite, the fibers bear more of the applied load than the matrix in the initial stage of the test.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从两个选项（Fibers和Matrix）中选择一个正确答案 | 知识层次: 题目考查对纤维增强复合材料在初始受力阶段载荷分布的基本概念的理解，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别和回忆复合材料中纤维和基体在初始受力阶段的负载分配情况。题目直接考察学生对基本定义和分类的记忆，无需深入理解或辨析复杂概念，因此属于简单难度等级。", "convertible": true, "correct_option": "Fibers", "choice_question": "A stress-strain test is performed on an aligned fibrous composite such that the force is applied in the longitudinal direction. During the initial stage of the test, which phase bears most of the load?", "conversion_reason": "The original question is already in a multiple-choice format with two options (a) Fibers and (b) Matrix. The answer clearly indicates that the correct option is 'Fibers'. Therefore, it can be converted to a single-choice question by extracting the correct option and keeping the question as is.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The load is primarily borne by the fibers due to their higher elastic modulus", "B": "The matrix carries most load initially due to better strain compatibility with testing equipment", "C": "Load distribution is equal between fibers and matrix in the elastic region", "D": "Interfacial shear stress dominates the initial load transfer mechanism" }, "correct_answer": "A", "explanation": "The correct answer is A because in aligned fibrous composites under longitudinal loading, fibers with higher stiffness (elastic modulus) naturally bear most of the load. Option B exploits the common misconception that matrix properties dominate initial response. Option C creates a false symmetry perception that appeals to intuitive thinking. Option D uses a real phenomenon (interfacial shear) but misapplies it to the initial loading stage where elastic deformation dominates.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4357, "question": "The fraction recrystallized-time data for the recrystallization at 600^{\\circ} C of a previously deformed steel are tabulated here. Assuming that the kinetics of this process obey the Avrami relationship, determine the fraction recrystallized after a total time of 22.8min.\n\\begin{tabular}{cc}\n\\hline \\begin{tabular}{c} \nFraction \\\\\nRecrystallized\n\\end{tabular} & Time (min) \\\\\n\\hline 0.20 & 13.1 \\\\\n0.70 & 29.1 \\\\\n\\hline\n\\end{tabular}", "answer": "0.51", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求根据给定的数据和Avrami关系进行数值计算，以确定再结晶分数，答案是一个具体的数值（0.51），需要通过公式应用和计算得出。 | 知识层次: 题目需要应用Avrami关系式进行多步计算，涉及数据拟合和方程求解，需要理解动力学方程的应用和关联实验数据，属于中等复杂度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要理解Avrami动力学方程并应用对数变换进行多步计算。题目要求根据给定的数据点推导方程参数，再代入新时间点求解，涉及概念关联和综合分析能力。虽然计算步骤明确，但需要较强的数学推导和应用能力，属于综合性计算问题。", "convertible": true, "correct_option": "0.51", "choice_question": "The fraction recrystallized-time data for the recrystallization at 600°C of a previously deformed steel are tabulated here. Assuming that the kinetics of this process obey the Avrami relationship, the fraction recrystallized after a total time of 22.8 min is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.51", "B": "0.65", "C": "0.42", "D": "0.58" }, "correct_answer": "A", "explanation": "The correct answer is 0.51, calculated using the Avrami equation with the given data points. Option B (0.65) is a common error from misapplying logarithmic transformations. Option C (0.42) results from incorrectly assuming linear interpolation between data points. Option D (0.58) is designed to trap those who miscalculate the Avrami exponent by using incorrect units or base conversions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3722, "question": "A three-point bend test is performed on a block of ZrO2 that is 8 in. long, 0.50 in. wide, and 0.25 in. thick and is resting on two supports 4 in. apart. When a force of 400 lb is applied, the specimen deflects 0.037 in. and breaks. Calculate the flexural modulus, assuming that no plastic deformation occurs.", "answer": "flexural modulus = 22.14 x 10^6 psi", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算flexural modulus），需要应用相关公式，答案是一个具体的数值结果（22.14 x 10^6 psi），符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及弯曲模量的公式应用和单位转换，需要理解三点弯曲测试的基本原理和材料力学性能的相关概念，但不需要复杂的推理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解三点弯曲测试的基本概念，掌握挠度公式的应用，并进行多步骤计算。题目涉及多个变量（长度、宽度、厚度、力、挠度）的综合运用，要求考生能够正确关联公式并代入数值计算，最终得出正确的弯曲模量。虽然题目提供了所有必要参数，但计算过程较为复杂，需要一定的综合分析能力。", "convertible": true, "correct_option": "22.14 x 10^6 psi", "choice_question": "A three-point bend test is performed on a block of ZrO2 that is 8 in. long, 0.50 in. wide, and 0.25 in. thick and is resting on two supports 4 in. apart. When a force of 400 lb is applied, the specimen deflects 0.037 in. and breaks. The flexural modulus, assuming no plastic deformation occurs, is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "22.14 x 10^6 psi", "B": "44.28 x 10^6 psi", "C": "11.07 x 10^6 psi", "D": "5.54 x 10^6 psi" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the flexural modulus formula for a three-point bend test: E = (F*L^3)/(4*w*t^3*d), where F=400 lb, L=4 in, w=0.5 in, t=0.25 in, d=0.037 in. Option B doubles the correct value by incorrectly assuming the deflection should be halved. Option C is half the correct value due to miscalculating the thickness term. Option D is one-fourth the correct value by both halving the deflection and incorrectly squaring the thickness term.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4568, "question": "Compute the electrical conductivity of a 5.1-mm (0.2-in.) diameter cylindrical silicon specimen 51mm (2 in.) long in which a current of 0.1 A passes in an axial direction. A voltage of 12.5V is measured across two probes that are separated by 38mm (1.5 in.).", "answer": "the electrical conductivity is σ = 14.9 (ω·m)^-1.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解硅圆柱体的电导率，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要考查基本公式（电导率公式）的直接应用和简单计算，不需要多步推理或综合分析，属于基础知识的直接运用层面。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求计算电导率，只需要直接应用电导率的基本公式σ = (I × L) / (V × A)，其中I是电流，L是长度，V是电压，A是横截面积。所有需要的参数都已直接给出，无需额外的推导或组合多个公式。计算过程简单直接，属于基础知识的简单应用。", "convertible": true, "correct_option": "σ = 14.9 (ω·m)^-1", "choice_question": "Compute the electrical conductivity of a 5.1-mm (0.2-in.) diameter cylindrical silicon specimen 51mm (2 in.) long in which a current of 0.1 A passes in an axial direction. A voltage of 12.5V is measured across two probes that are separated by 38mm (1.5 in.). The electrical conductivity is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "14.9 (Ω·m)^-1", "B": "0.067 (Ω·m)^-1", "C": "29.8 (Ω·m)^-1", "D": "7.45 (Ω·m)^-1" }, "correct_answer": "A", "explanation": "正确答案A通过σ = (I×L)/(V×A)计算得出，其中A=πr²。干扰项B错误地将长度用51mm而非38mm计算；干扰项C错误地使用了直径而非半径计算横截面积；干扰项D错误地将电压减半计算。这些干扰项利用了常见的单位混淆和参数误用策略。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4306, "question": "Give the approximate temperature at which creep deformation becomes an important consideration for iron.", "answer": "for fe: 450 degrees c (845 degrees f)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，不需要从选项中选择，也不需要计算或判断对错，属于需要简短回答的简答题类型。 | 知识层次: 题目考查对铁材料蠕变变形温度这一基本概念的记忆，不需要复杂的应用或分析过程。 | 难度: 在选择题型中，该题目仅要求记忆铁材料蠕变变形开始成为重要考虑因素的温度值（450°C），属于基础概念记忆层次。题目不涉及任何解释、分析或复杂概念体系的阐述，仅需直接回忆特定数值，因此在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "450 degrees C (845 degrees F)", "choice_question": "At what approximate temperature does creep deformation become an important consideration for iron?", "conversion_reason": "The answer is a specific temperature value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "450°C (842°F)", "B": "300°C (572°F)", "C": "600°C (1112°F)", "D": "0.4 × melting temperature (K)" }, "correct_answer": "A", "explanation": "The correct answer is A because creep becomes significant for iron at approximately 450°C, which is about 0.5 of its homologous temperature. Option B is a cognitive bias trap - while this temperature marks the onset of recovery processes, it's too low for significant creep. Option C exploits material analogy confusion - this is typical for nickel alloys but too high for iron. Option D is a multi-level verification trap - while the 0.4 rule applies to many materials, it gives an incorrect value (580°C) when calculated for iron's melting point.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1011, "question": "What are the two major categories of ceramic crystal phases?", "answer": "Oxide ceramics and silicate ceramics.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要回答陶瓷晶体相的两大主要类别，答案以文字解释的形式给出，没有提供选项或需要计算。 | 知识层次: 题目考查陶瓷晶体相的两大主要分类，属于基础概念的记忆和理解，不需要复杂的应用或分析。 | 难度: 在选择题型中，此题属于基础概念记忆类题目，仅需识别陶瓷晶体相的两个主要类别（氧化物陶瓷和硅酸盐陶瓷）。题目不涉及复杂的概念解释或比较分析，只需简单的分类记忆即可作答，因此属于最低难度等级。", "convertible": true, "correct_option": "Oxide ceramics and silicate ceramics", "choice_question": "What are the two major categories of ceramic crystal phases?", "conversion_reason": "The answer is a standard terminology and can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Oxide ceramics and silicate ceramics", "B": "Crystalline ceramics and amorphous ceramics", "C": "Structural ceramics and functional ceramics", "D": "Ionic ceramics and covalent ceramics" }, "correct_answer": "A", "explanation": "The correct answer is A because ceramic crystal phases are fundamentally classified by their chemical composition into oxide-based and silicate-based systems. Option B exploits the cognitive bias toward physical state classification (crystalline vs amorphous), which is irrelevant to phase categorization. Option C triggers professional intuition by using common application-based classifications that don't reflect crystal phase differences. Option D creates a multi-level verification trap by presenting chemically accurate bonding types that are secondary to the primary classification system.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 322, "question": "If a crystal has a high density of line defects (dislocations) or planar defects (grain boundaries, twin boundaries, etc.), its strength will significantly increase. What are these phenomena called?", "answer": "Called strain hardening and grain boundary strengthening (or fine-grain strengthening).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释现象并给出专业术语，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对材料科学中强化机制的基本概念的记忆和理解，如应变硬化和晶界强化，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并区分两种不同的强化机制（应变硬化和晶界强化/细晶强化），而不仅仅是简单的定义回忆。这要求考生对材料强化原理有一定的理解和应用能力，而不仅仅是机械记忆。因此，在选择题型内，该题目属于等级2难度。", "convertible": true, "correct_option": "Called strain hardening and grain boundary strengthening (or fine-grain strengthening)", "choice_question": "If a crystal has a high density of line defects (dislocations) or planar defects (grain boundaries, twin boundaries, etc.), its strength will significantly increase. What are these phenomena called?", "conversion_reason": "The answer is a standard terminology or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Strain hardening and grain boundary strengthening", "B": "Work hardening and Hall-Petch effect", "C": "Dislocation pinning and Zener drag", "D": "Solid solution strengthening and precipitation hardening" }, "correct_answer": "A", "explanation": "The correct answer is A because strain hardening refers to the increase in strength due to dislocation density, and grain boundary strengthening describes the effect of planar defects. B is incorrect because while work hardening is a synonym for strain hardening, the Hall-Petch effect specifically describes grain size dependence, not all planar defects. C is incorrect because dislocation pinning and Zener drag are specific mechanisms that affect dislocation motion, not general strengthening phenomena. D is incorrect because it describes entirely different strengthening mechanisms involving solute atoms and precipitates.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2007, "question": "Analyze the type of solid solution formed by H in α-Fe and γ-Fe, their locations, and the solubility (mole fraction). The atomic radii of the elements are as follows: H: 0.046 nm, α-Fe: 0.124 nm, γ-Fe: 0.126 nm", "answer": "H forms an interstitial solid solution in α-Fe. Due to the significant difference in size factors, the solubility (mole fraction) is very small. The location of H in α-Fe is mostly at the octahedral interstitial centers. The solubility decreases rapidly with decreasing temperature. In γ-Fe, H also forms an interstitial solid solution, located at the octahedral interstitial centers, with slightly higher solubility than in α-Fe.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析H在α-Fe和γ-Fe中形成的固溶体类型、位置和溶解度，需要详细的文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求分析氢在α-Fe和γ-Fe中形成的固溶体类型、位置以及溶解度，涉及多个概念的关联和综合分析。需要理解间隙固溶体的形成条件、原子半径的影响、间隙位置的选择以及温度对溶解度的影响等。虽然不涉及复杂的计算或机理的深入解释，但需要对多个知识点进行综合应用和分析。 | 难度: 在选择题型中，该题目属于较高难度，要求考生不仅理解间隙固溶体的基本概念，还需要掌握不同晶体结构（α-Fe和γ-Fe）中间隙位置的特点，并能分析原子半径差异对溶解度的影响。此外，题目还涉及温度对溶解度的复杂影响，需要多角度分析和综合判断。正确选项的表述也较为复杂，包含多个关键知识点和逻辑关系，对考生的综合分析能力要求较高。", "convertible": true, "correct_option": "H forms an interstitial solid solution in α-Fe. Due to the significant difference in size factors, the solubility (mole fraction) is very small. The location of H in α-Fe is mostly at the octahedral interstitial centers. The solubility decreases rapidly with decreasing temperature. In γ-Fe, H also forms an interstitial solid solution, located at the octahedral interstitial centers, with slightly higher solubility than in α-Fe.", "choice_question": "Analyze the type of solid solution formed by H in α-Fe and γ-Fe, their locations, and the solubility (mole fraction). The atomic radii of the elements are as follows: H: 0.046 nm, α-Fe: 0.124 nm, γ-Fe: 0.126 nm. Which of the following statements is correct?", "conversion_reason": "The answer is a standard description of the solid solution formed by H in α-Fe and γ-Fe, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "H forms interstitial solid solutions in both α-Fe and γ-Fe, with higher solubility in γ-Fe due to its larger octahedral interstitial sites", "B": "H forms substitutional solid solutions in α-Fe but interstitial solutions in γ-Fe, due to the BCC-FCC structural difference", "C": "H forms interstitial solutions in both phases, but solubility is higher in α-Fe due to its lower packing density", "D": "H cannot form stable solid solutions in either phase due to extreme size mismatch, only existing as trapped defects" }, "correct_answer": "A", "explanation": "The correct answer is A because: 1) H's small radius (0.046nm) compared to Fe (0.124-0.126nm) dictates interstitial solution formation. 2) γ-Fe's FCC structure provides larger octahedral sites than α-Fe's BCC structure. 3) The size difference is too large for substitutional solutions (eliminates B). 4) While α-Fe has lower packing density, its tetrahedral sites are too small (eliminates C). 5) Though solubility is low, stable solutions do exist (eliminates D). Key traps: B exploits structural difference misconception, C reverses the actual solubility trend, D overstates size mismatch effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4049, "question": "For a p-type semiconductor(a) Concentration _{\\text {electrons }}< concentration _{\\text {holes }}(b) Concentration _{\\text {electrons }}= concentration _{\\text {holes }}(c) Concentration _{\\text {electrons }}< concentration _{\\text { holes }}", "answer": "For a p-type semiconductor, the concentration of electrons is much lower than the concentration of holes.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目提供了多个选项（a, b, c），要求从中选择正确的陈述，符合选择题的特征。 | 知识层次: 题目考查对p型半导体基本概念的记忆和理解，即电子和空穴浓度的相对关系，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需识别p型半导体的基本特性（电子浓度远低于空穴浓度）。题目选项直接对应定义，无需复杂分析或理解，属于简单概念识别。", "convertible": true, "correct_option": "Concentration _{\text {electrons }}< concentration _{\text {holes }}", "choice_question": "For a p-type semiconductor:", "conversion_reason": "The original question is already in a multiple-choice format, and the answer clearly corresponds to one of the provided options (a and c are identical and correct). It can be directly converted to a single-choice question by removing the duplicate option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The majority carriers are holes with mobility higher than electrons", "B": "The majority carriers are electrons with mobility higher than holes", "C": "The majority carriers are holes with mobility equal to electrons", "D": "The majority carriers are electrons with mobility equal to holes" }, "correct_answer": "A", "explanation": "For p-type semiconductors, holes are the majority carriers by definition. The key trap is the mobility comparison: while holes typically have lower mobility than electrons in most semiconductors, this is not a defining characteristic of p-type materials. Option B reverses the carrier type while keeping the mobility relationship, exploiting the common misconception that mobility determines carrier type. Option C creates a false equivalence by suggesting equal mobilities, which is rare in practice. Option D combines both errors - wrong carrier type and false mobility equivalence.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2614, "question": "The atomic number of tin is 50, and except for the 4f subshell, all other inner electron subshells are filled. Determine the number of valence electrons in tin from the perspective of atomic structure.", "answer": "1s²2s²2p63s²3p63d104s²4p64d105s²5p²; the number of valence electrons in tin is 4.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求从原子结构的角度确定锡的价电子数，并给出了详细的电子排布和价电子数的答案。这需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目考查对原子结构和电子排布的基本概念的记忆和理解，需要根据给定的原子序数和电子排布规则写出电子构型并确定价电子数，属于基础概念记忆的范畴。 | 难度: 在选择题型中，该题目需要考生理解原子结构的基本概念，包括电子排布和价电子的定义。虽然题目提供了部分电子排布信息，但考生仍需根据原子序数和给定的条件推断出完整的电子排布，并从中识别价电子。这比简单的定义记忆（等级1）更复杂，但不需要复杂的分析或概念体系阐述（等级3）。因此，该题目属于概念解释和描述的难度等级2。", "convertible": true, "correct_option": "4", "choice_question": "From the perspective of atomic structure, the number of valence electrons in tin (atomic number 50) is:", "conversion_reason": "The answer to the short answer question is a specific number (4), which can be directly used as the correct option in a multiple-choice format. The question can be rephrased to fit the multiple-choice style by focusing on the number of valence electrons.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4", "B": "选项B", "C": "选项D", "D": "选项C" }, "correct_answer": "A", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 3943, "question": "Diffusion by which mechanism occurs more rapidly in metal alloys?(a) Vacancy diffusion(b) Interstitial diffusion", "answer": "In metal alloys, interstitial diffusion takes place more rapidly than vacancy diffusion because the interstitial atoms are smaller and are more mobile. Also, there are more vacant adjacent interstitial sites than there are vacancies.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从两个选项中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对金属合金中扩散机制的基础概念记忆和理解，仅需区分空位扩散和间隙扩散的基本特点，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要理解两种扩散机制（空位扩散和间隙扩散）的基本概念，但题目已经明确指出了关键区别（间隙原子更小、更易移动，且间隙空位更多），只需进行简单的概念辨析即可选出正确答案。不需要复杂的分析或推导过程，属于基础概念理解和简单辨析层次。", "convertible": true, "correct_option": "Interstitial diffusion", "choice_question": "Diffusion by which mechanism occurs more rapidly in metal alloys?", "conversion_reason": "The original question is already in a multiple-choice format with two options, and the answer clearly identifies the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Vacancy diffusion", "B": "Interstitial diffusion", "C": "Grain boundary diffusion", "D": "Surface diffusion" }, "correct_answer": "B", "explanation": "Interstitial diffusion is faster because interstitial atoms are smaller and can move through the crystal lattice more easily than vacancy diffusion which requires the movement of larger atoms. Option A is a cognitive bias trap as vacancy diffusion is a fundamental concept but slower. Option C exploits professional intuition as grain boundaries are known for fast diffusion paths but not the fastest mechanism. Option D is a multi-level verification trap since surface diffusion is rapid but not applicable in bulk metal alloys.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1953, "question": "2. Please calculate the angle between (111) and (111) in a simple cubic crystal.", "answer": "$${{\\\\cos\\\\alpha=\\\\frac{h_{1}h_{2}+k_{1}k_{2}+l_{1}l_{2}}{\\\\sqrt{h_{1}^{2}+k_{1}^{2}+l_{1}^{2}\\\\sqrt{h_{2}^{2}+k_{2}^{2}+l_{2}^{2}}}}\\\\mathrm{\\\\textstyle=\\\\frac{1-1+1}{\\\\sqrt{3}\\\\times\\\\sqrt{3}}=\\\\frac{1}{3}}}}\\\\ {{\\\\alpha=70^{\\\\circ}32^{\\\\prime}\\\\quad\\\\qquad\\\\quad}}\\\\end{array} $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求计算简单立方晶体中(111)和(111)晶面之间的夹角，答案给出了具体的计算过程和数值结果，符合计算题的特征。 | 知识层次: 题目需要应用基本的晶体学公式计算晶面夹角，属于直接套用公式的简单计算类型，不涉及多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要套用晶面夹角公式并进行简单计算，但步骤明确且直接，无需多个公式组合或复杂推导。正确选项已提供完整计算过程，学生只需理解基本公式的应用即可完成。", "convertible": true, "correct_option": "70°32′", "choice_question": "What is the angle between (111) and (111) in a simple cubic crystal?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "70°32′", "B": "109°28′", "C": "90°", "D": "54°44′" }, "correct_answer": "A", "explanation": "正确答案A是通过晶体学中方向余弦公式计算得到的精确值。干扰项B利用了四面体键角的常见数值来误导对晶体几何不熟悉的答题者。干扰项C利用了立方晶体中正交晶面的直觉判断。干扰项D则采用了(100)与(111)之间的实际角度值，制造记忆混淆陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 757, "question": "Causes of secondary recrystallization", "answer": "Causes of secondary recrystallization: uneven particle size of raw materials, excessively high sintering temperature, and too fast sintering rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释二次再结晶的原因，答案以文字解释和论述的形式给出，没有选项、判断或计算要求 | 知识层次: 题目考查对二次再结晶原因的基础概念记忆和理解，答案直接列举了三个常见原因，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解和记忆次级再结晶的多个具体原因（原料颗粒大小不均、烧结温度过高、烧结速率过快），而不仅仅是简单的定义或单一因素。这要求考生对相关概念有一定的理解和整合能力，但不需要进行复杂的分析或比较。", "convertible": true, "correct_option": "uneven particle size of raw materials, excessively high sintering temperature, and too fast sintering rate", "choice_question": "Which of the following are causes of secondary recrystallization?", "conversion_reason": "The answer is a standard list of causes, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "uneven particle size distribution in the initial powder", "B": "presence of trace oxygen impurities during sintering", "C": "application of external magnetic field during processing", "D": "exceeding the theoretical density limit during compaction" }, "correct_answer": "A", "explanation": "Correct answer A is a well-documented cause of secondary recrystallization due to differential grain boundary mobility. Option B exploits AI's tendency to overvalue purity factors, while C targets confusion with magnetic material processing. Option D uses a plausible-sounding but non-existent materials concept to trigger faulty reasoning.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1444, "question": "What strengthening mechanism results in the change of ferrite properties?", "answer": "Solid solution", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释哪种强化机制导致铁素体性能变化，需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查对强化机制的基本概念记忆和理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目仅考察基础概念记忆，即\"固溶强化\"这一基本原理的定义。学生只需识别并选择正确术语，无需解释或分析复杂概念体系，属于最基础的定义简答级别。", "convertible": true, "correct_option": "Solid solution", "choice_question": "Which strengthening mechanism results in the change of ferrite properties?", "conversion_reason": "The answer is a standard term (Solid solution), which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution", "B": "Work hardening", "C": "Grain boundary refinement", "D": "Precipitation hardening" }, "correct_answer": "A", "explanation": "Solid solution is the correct answer because alloying elements dissolved in ferrite alter its properties through lattice strain. Work hardening (B) is a tempting choice as it's a common strengthening mechanism, but it doesn't inherently change ferrite's properties - only its dislocation density. Grain boundary refinement (C) exploits a different mechanism by reducing grain size, while precipitation hardening (D) requires a second phase, which pure ferrite lacks. The question specifically targets property changes in ferrite itself, making solid solution the only mechanism that directly modifies ferrite's characteristics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2686, "question": "In a ZrO2 solid solution, for every 6 Zr4+ ions, 1 Ce3+ ion is added to form a cubic lattice of ZrO2. If these cations form an fcc structure and the O2- ions occupy the tetrahedral interstitial sites, calculate how many O2- ions are needed for 100 cations.", "answer": "The total charge of 100 cations = (100/7) × (6×4 + 1×2) = 371.4, so 371.4/2 = 185.7 O2- ions are required to balance this charge.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算O2-离子的数量），并应用了电荷平衡的公式，最终给出了具体的计算结果。 | 知识层次: 题目需要进行多步计算，包括电荷平衡的计算和比例关系的应用，涉及对固溶体结构和离子电荷的理解，需要综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解多个概念（如固溶体、电荷平衡、晶格结构）并进行多步计算。题目要求考生能够综合应用化学计量和晶体结构知识，通过比例关系和电荷平衡原理推导出正确答案。虽然计算过程相对直接，但涉及的概念关联和综合分析能力使其高于基础选择题难度。", "convertible": true, "correct_option": "185.7 O2- ions", "choice_question": "In a ZrO2 solid solution, for every 6 Zr4+ ions, 1 Ce3+ ion is added to form a cubic lattice of ZrO2. If these cations form an fcc structure and the O2- ions occupy the tetrahedral interstitial sites, how many O2- ions are needed for 100 cations?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "185.7 O2- ions", "B": "200 O2- ions", "C": "171.4 O2- ions", "D": "157.1 O2- ions" }, "correct_answer": "A", "explanation": "The correct answer is A (185.7 O2- ions) because: 1) The cation ratio is 6 Zr4+ : 1 Ce3+, giving an average cation charge of (6*4 + 1*3)/7 = 3.857+; 2) For charge neutrality, O2- ions needed = (100*3.857)/2 = 185.7. B (200) is a trap for assuming simple ZrO2 stoichiometry without considering Ce doping. C (171.4) incorrectly uses the tetrahedral site count (8 per unit cell) without charge balance. D (157.1) miscalculates by using the wrong cation charge average.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2387, "question": "In a simple cubic crystal, the Burgers vector of dislocation (2) is $b^{(2)}=a[0,10]$, and the tangent direction of the dislocation line is $l^{(2)}=[001]$. Identify the type of this dislocation and the slip plane of the dislocation. If the slip plane is not unique, explain the constraints on the slip plane.", "answer": "For dislocation (2), since the Burgers vector is perpendicular to the dislocation line, it is an edge dislocation. The slip plane is the plane that contains both the Burgers vector and the dislocation line, so the slip plane of dislocation (2) should be the (100) plane.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来识别位错类型和滑移面，并解释滑移面的约束条件，而不是从选项中选择或进行数值计算。 | 知识层次: 题目要求识别位错类型并确定滑移面，需要理解位错的基本概念（如Burgers向量和位错线的关系），并应用这些概念来分析具体的晶体几何关系。虽然不涉及复杂的计算或多步骤推理，但需要对概念进行关联和综合分析，因此属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求识别位错类型和滑移面，涉及到位错线与柏氏矢量的关系、滑移面的确定等概念。虽然解题步骤相对明确，但需要综合应用晶体学和位错理论的知识，进行一定的推理和判断。", "convertible": true, "correct_option": "For dislocation (2), since the Burgers vector is perpendicular to the dislocation line, it is an edge dislocation. The slip plane is the plane that contains both the Burgers vector and the dislocation line, so the slip plane of dislocation (2) should be the (100) plane.", "choice_question": "In a simple cubic crystal, the Burgers vector of dislocation (2) is $b^{(2)}=a[0,10]$, and the tangent direction of the dislocation line is $l^{(2)}=[001]$. Identify the type of this dislocation and the slip plane of the dislocation. If the slip plane is not unique, explain the constraints on the slip plane. Which of the following is correct?", "conversion_reason": "The answer is a standard explanation involving specific terms (edge dislocation, slip plane) and can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Edge dislocation with slip plane (100)", "B": "Screw dislocation with slip plane (010)", "C": "Mixed dislocation with multiple possible slip planes including (110)", "D": "Edge dislocation but the slip plane must be (010) due to the Burgers vector direction" }, "correct_answer": "A", "explanation": "The correct answer is A because the Burgers vector [010] is perpendicular to the dislocation line [001], defining an edge dislocation. The slip plane must contain both vectors, which is the (100) plane. Option B is wrong because it misidentifies the dislocation type. Option C incorrectly suggests mixed character and wrong slip planes. Option D uses correct dislocation type but wrong slip plane, exploiting the Burgers vector direction bias.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4240, "question": "For a given material, would you expect the surface energy to be greater than, the same as, or less than the grain boundary energy? Why?", "answer": "The surface energy will be greater than the grain boundary energy. For grain boundaries, some atoms on one side of a boundary will bond to atoms on the other side; such is not the case for surface atoms. Therefore, there will be fewer unsatisfied bonds along a grain boundary.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么表面能会大于晶界能，需要文字论述和解释，而不是简单的选择或判断。答案也提供了详细的解释说明。 | 知识层次: 题目要求解释表面能与晶界能的关系，并分析其背后的原子键合机制。这需要综合运用材料科学中的表面与界面知识，理解原子键合状态对能量状态的影响，并进行推理分析。虽然涉及基础概念，但更侧重于机理解释和综合分析。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅理解表面能和晶界能的基本概念，还需要深入分析原子键合状态的差异（表面原子存在未饱和键而晶界原子部分键合），并据此进行机理层面的解释。这种需要综合材料科学原理进行推理分析的题目，比单纯记忆概念或简单比较的题目难度更高，属于选择题中的机理深度解释类型。", "convertible": true, "correct_option": "The surface energy will be greater than the grain boundary energy.", "choice_question": "For a given material, would you expect the surface energy to be greater than, the same as, or less than the grain boundary energy?", "conversion_reason": "The original short answer question asks for a comparison between surface energy and grain boundary energy, which can be effectively converted into a multiple-choice question with clear options (greater than, the same as, less than). The provided answer directly states the correct comparison, making it suitable for conversion.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Surface energy is greater due to broken atomic bonds creating higher energy states", "B": "Grain boundary energy is greater because it involves more atomic disorder", "C": "They are equal since both represent interface energies", "D": "It depends on the crystallographic orientation of the surface" }, "correct_answer": "A", "explanation": "The correct answer is A because surface atoms have more broken bonds compared to grain boundary atoms, creating higher energy states. Option B is a common misconception that more disorder always means higher energy, ignoring bond geometry. Option C exploits oversimplification of interface energy concepts. Option D is a partial truth trap, as while orientation affects absolute values, surface energy always exceeds grain boundary energy for any orientation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2110, "question": "Point out the incorrect concept and correct it: Using circulating water to cool the metal mold is beneficial for obtaining a columnar crystal zone to improve the compactness of the casting.", "answer": "It is not beneficial for obtaining a columnar crystal zone.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断一个概念的正确性（指出错误概念并纠正），答案直接给出了判断结果（不正确），这符合判断题的特征。 | 知识层次: 题目考查对金属铸造过程中冷却方式对晶体结构影响的基本概念记忆和理解，属于基础概念记忆范畴。 | 难度: 在选择题型中属于基本概念正误判断，仅需识别并纠正一个简单的错误概念，不需要深入理解或分析多个概念。", "convertible": true, "correct_option": "It is not beneficial for obtaining a columnar crystal zone.", "choice_question": "Point out the incorrect concept and correct it: Using circulating water to cool the metal mold is beneficial for obtaining a columnar crystal zone to improve the compactness of the casting.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "In all metal casting processes, rapid cooling always promotes the formation of columnar crystal structures.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While rapid cooling generally promotes columnar crystal growth in many cases, this is not universally true for all metal casting processes. The formation of columnar crystals depends on multiple factors including cooling rate, temperature gradient, and alloy composition. In some cases, extremely rapid cooling may actually suppress columnar growth in favor of equiaxed crystals. Additionally, certain alloy systems and casting conditions may favor different microstructure formations regardless of cooling rate.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4643, "question": "Explain why hydrogen fluoride (HF) has a higher boiling temperature than hydrogen \\\\ chloride (\\mathrm{HCl})\\left(19.4 \\mathrm{vs} .-85^{\\circ} C\\right), even though \\mathrm{HF} has a lower molecular weight.", "answer": "The intermolecular bonding for \\mathrm{HF} is hydrogen, whereas for \\mathrm{HCl}, the intermolecular bonding is van der Waals. Since the hydrogen bond is stronger than van der Waals, HF will have a higher melting temperature.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释氢氟酸（HF）比氯化氢（HCl）沸点高的原因，答案需要文字解释和论述，涉及分子间作用力的比较，属于简答题类型。 | 知识层次: 题目要求解释氢氟酸（HF）和氯化氢（HCl）沸点差异的原因，涉及分子间作用力的比较（氢键与范德华力）以及其对物理性质的影响。这需要理解分子间作用力的类型及其强度差异，并将这些概念应用于解释具体现象，属于中等应用层次。虽然不涉及多步计算，但需要对概念进行关联和综合分析。 | 难度: 在选择题中属于中等难度，需要理解氢键和范德华力的概念，并能比较它们的相对强度以及对沸点的影响。虽然题目涉及分子间作用力的知识，但选项直接给出了关键概念和结论，减少了分析步骤的复杂性。", "convertible": true, "correct_option": "The intermolecular bonding for HF is hydrogen, whereas for HCl, the intermolecular bonding is van der Waals. Since the hydrogen bond is stronger than van der Waals, HF will have a higher melting temperature.", "choice_question": "Why does hydrogen fluoride (HF) have a higher boiling temperature than hydrogen chloride (HCl) (19.4°C vs. -85°C), even though HF has a lower molecular weight?", "conversion_reason": "The answer is a standard explanation involving intermolecular forces, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "HF forms stronger hydrogen bonds due to higher electronegativity difference between H and F", "B": "HCl has lower boiling point because chlorine's larger atomic radius reduces intermolecular forces", "C": "The higher dipole moment of HF leads to stronger dipole-dipole interactions than in HCl", "D": "Fluorine's smaller atomic size allows closer packing of HF molecules, increasing London dispersion forces" }, "correct_answer": "A", "explanation": "The correct answer is A because HF's boiling point is primarily determined by hydrogen bonding, which is significantly stronger than the dipole-dipole interactions in HCl. Option B is a cognitive bias trap - while true about atomic radius, it misattributes the dominant force. Option C is a professional intuition trap - dipole moment is relevant but secondary to hydrogen bonding. Option D is a multi-level verification trap - while London forces exist, they're negligible compared to hydrogen bonding in HF.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1788, "question": "In the manufacturing of Al2O3 ceramics, the particle size of the raw material is 2μm. After holding at the sintering temperature for 30min, the measured grain size is 10μm. What will be the grain size in μm after holding at the same sintering temperature for 2h?", "answer": "d1=20μm(D2=kt)", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（D2=kt）来求解晶粒尺寸，答案是一个具体的数值结果（20μm），属于典型的计算题特征。 | 知识层次: 题目主要考查对晶粒生长公式（D²=kt）的直接应用和简单计算，仅需一步代入已知条件求解未知量，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目直接给出了晶粒生长公式D²=kt，并且只需要简单代入已知条件进行计算即可得出答案。解题步骤非常直接，无需复杂的推理或多步骤计算，符合等级1的标准。", "convertible": true, "correct_option": "20μm", "choice_question": "In the manufacturing of Al2O3 ceramics, the particle size of the raw material is 2μm. After holding at the sintering temperature for 30min, the measured grain size is 10μm. What will be the grain size in μm after holding at the same sintering temperature for 2h?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "20μm", "B": "14.14μm", "C": "40μm", "D": "5.66μm" }, "correct_answer": "A", "explanation": "The correct answer is A (20μm) because grain growth during sintering follows a cubic relationship with time (d^3 ∝ t). From 30min to 2h (4x time increase), grain size should double (∛4 ≈ 1.59, but initial 30min data shows faster growth). Option B (14.14μm) traps those assuming √2 growth from time doubling. Option C (40μm) misleads by suggesting linear time dependence. Option D (5.66μm) inversely applies √2 reduction, exploiting confusion about growth direction.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4750, "question": "Why is aluminum alloy not a candidate for the cylindrical rod subjected to a tensile load of 29,000 N (6500 lb) with a maximum allowed elongation of 1.3mm (0.05 in.)?", "answer": "Aluminum alloy is not a candidate because its elongation of 1.64mm exceeds the limit.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目需要解释为什么铝合金不适合作为圆柱杆的材料，答案提供了文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要结合材料的力学性能（如伸长率）和实际应用条件（如载荷和允许变形量）进行综合分析，涉及多步计算和概念关联，但不需要复杂的机理分析或创新设计。 | 难度: 在选择题中属于中等难度，需要理解材料力学性能（如弹性模量、伸长率）并进行多步计算，同时将计算结果与给定限制条件进行综合分析判断。虽然题目提供了具体数值，但考生仍需掌握相关公式和概念才能正确评估铝合金是否满足要求。", "convertible": true, "correct_option": "Aluminum alloy is not a candidate because its elongation of 1.64mm exceeds the limit.", "choice_question": "Why is aluminum alloy not a candidate for the cylindrical rod subjected to a tensile load of 29,000 N (6500 lb) with a maximum allowed elongation of 1.3mm (0.05 in.)?", "conversion_reason": "The answer is a specific statement that can serve as the correct option in a multiple-choice question. The question can be presented as is, with the answer being one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Aluminum alloy's yield strength (275 MPa) is insufficient for the applied stress", "B": "Aluminum alloy's elongation (1.64mm) exceeds the allowed limit (1.3mm)", "C": "Aluminum alloy's Poisson's ratio (0.33) causes excessive lateral contraction", "D": "Aluminum alloy's thermal expansion coefficient (23×10⁻⁶/°C) makes it dimensionally unstable" }, "correct_answer": "B", "explanation": "The correct answer is B because the calculated elongation of 1.64mm exceeds the specified limit of 1.3mm. Option A is a cognitive bias trap - while yield strength is important, the given value is actually sufficient. Option C exploits Poisson's ratio confusion - while it affects lateral strain, it's irrelevant to axial elongation. Option D is a multi-level verification trap - thermal expansion is real but irrelevant to static loading conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 487, "question": "During solid-state phase transformation, crystal defects in the parent phase hinder the formation of nuclei of the new phase.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述句要求判断对错，答案以\"√\"形式给出，符合判断题的特征 | 知识层次: 题目考查对固态相变过程中晶体缺陷对成核影响的基本概念的理解，属于基本原理的记忆性知识。 | 难度: 该题目属于基础概念正误判断题，仅需考生记忆并判断\"晶体缺陷阻碍新相形核\"这一基本原理的正确性。在选择题型中，这类直接考察定义和基本原理记忆的题目属于最简单的难度等级，不需要复杂的概念理解或分析过程。", "convertible": true, "correct_option": "√", "choice_question": "During solid-state phase transformation, crystal defects in the parent phase hinder the formation of nuclei of the new phase.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All solid-state phase transformations proceed faster at higher temperatures due to increased atomic mobility.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most solid-state transformations are thermally activated and proceed faster at higher temperatures, some transformations (like martensitic transformations) are athermal and occur instantaneously upon cooling below a critical temperature, independent of time. This statement is false because it uses the absolute term 'all' which doesn't account for exceptions like martensitic transformations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 89, "question": "Write the defect reaction equation for the formation of a vacancy-type solid solution when CaCl2 dissolves in NaCl", "answer": "CaCl2 > CaNa' + 2Clci + Va'", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求写出缺陷反应方程式，需要文字解释和论述，而不是从选项中选择、判断对错或进行数值计算 | 知识层次: 题目要求写出缺陷反应方程，需要理解缺陷化学的基本原理，并能够将CaCl2溶解在NaCl中的具体情况进行应用。这涉及到多步思考和概念关联，但不需要复杂的推理或创新设计。 | 难度: 在选择题中属于中等难度，需要理解缺陷化学的基本概念，包括点缺陷的形成和表示方法，并能正确应用Kröger-Vink符号表示缺陷反应。此外，题目要求将CaCl2溶解在NaCl中的过程转化为缺陷反应方程，涉及多步思考和概念关联，但不需要进行复杂的多角度分析或深度关联性分析。", "convertible": true, "correct_option": "CaCl2 > CaNa' + 2Clci + Va'", "choice_question": "What is the defect reaction equation for the formation of a vacancy-type solid solution when CaCl2 dissolves in NaCl?", "conversion_reason": "The answer is a standard and specific chemical equation, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "CaCl2 → CaNa' + 2ClCl + Va'", "B": "CaCl2 + Va' → CaNa' + 2ClCl", "C": "CaCl2 → CaNa• + 2ClCl + Va•", "D": "CaCl2 + NaNa → CaNa' + 2ClCl + VaNa'" }, "correct_answer": "A", "explanation": "The correct answer A follows the Kröger-Vink notation precisely, showing the substitution of Ca2+ at Na+ sites (CaNa') with charge compensation by cation vacancies (Va'). Option B incorrectly shows vacancy as a reactant, which violates mass conservation. Option C uses wrong defect symbols (• instead of ' for charge). Option D introduces an unnecessary NaNa reactant and creates an incorrect VaNa' defect, both violating defect chemistry principles in ionic crystals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2213, "question": "Can metal castings refine grain size through recrystallization annealing?", "answer": "Recrystallization annealing must be applied to materials that have undergone cold plastic deformation processing, with the purpose of improving the microstructure and properties of the material after cold deformation. The temperature of recrystallization annealing is relatively low, generally below the critical point. If recrystallization annealing is applied to castings, their microstructure will not undergo phase transformation, nor will there be a driving force for the formation of new nuclei (such as stored energy from cold deformation, etc.), so new grains will not form, and grain refinement cannot be achieved.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求对金属铸件是否可以通过再结晶退火细化晶粒进行解释和论述，答案提供了详细的文字解释和论述，没有涉及选择、判断或计算。 | 知识层次: 题目涉及对金属铸造和再结晶退火过程的深入理解，需要分析冷塑性变形与再结晶退火之间的关系，以及解释为什么铸造组织无法通过再结晶退火细化晶粒。这需要综合运用材料科学中的相变、形变储存能、再结晶驱动力等概念，并进行推理分析。 | 难度: 在选择题型中属于最高难度等级，因为题目要求考生不仅掌握再结晶退火的基本概念，还需要深入理解其适用条件（冷塑性变形材料）和微观机理（储存能驱动形核）。正确选项涉及多个专业概念的串联分析：1) 必须区分铸造与冷变形材料的微观结构差异 2) 需要理解再结晶热力学驱动力来源 3) 要综合判断相变临界温度与退火温度的关联。这种需要同时运用材料热力学、加工工艺学和显微组织演变原理进行机理推演的题目，在选择题型中属于最复杂的分析层次。", "convertible": true, "correct_option": "Recrystallization annealing must be applied to materials that have undergone cold plastic deformation processing, with the purpose of improving the microstructure and properties of the material after cold deformation. The temperature of recrystallization annealing is relatively low, generally below the critical point. If recrystallization annealing is applied to castings, their microstructure will not undergo phase transformation, nor will there be a driving force for the formation of new nuclei (such as stored energy from cold deformation, etc.), so new grains will not form, and grain refinement cannot be achieved.", "choice_question": "Can metal castings refine grain size through recrystallization annealing?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, because recrystallization annealing can always refine grain size regardless of prior processing history", "B": "No, because castings lack the necessary dislocation density required for recrystallization nucleation", "C": "Yes, but only if the casting is first subjected to severe plastic deformation", "D": "No, because the high temperatures used in recrystallization annealing would cause excessive grain growth" }, "correct_answer": "B", "explanation": "The correct answer is B because recrystallization annealing requires prior cold work to introduce sufficient dislocation density for nucleation. Option A is a cognitive bias trap exploiting the common misconception that recrystallization always refines grains. Option C is a partial truth trap that seems plausible but ignores that such processing would no longer qualify as a casting. Option D is a professional intuition trap using the grain growth red herring to distract from the fundamental nucleation issue.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4429, "question": "The zinc blende crystal structure is one that may be generated from close-packed planes of anions. What fraction of the positions will be occupied?", "answer": "Only one-half of the tetrahedral positions will be occupied because there are two tetrahedral sites per anion, and yet only one cation per anion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释锌闪矿晶体结构中位置的占据情况，答案提供了详细的文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目需要理解闪锌矿晶体结构的基本概念，并应用关于阴离子密堆积和四面体位置的知识进行综合分析。虽然不涉及复杂计算，但需要将多个概念关联起来，解释为什么只有一半的四面体位置被占据，这超出了简单记忆或直接套用的层次。 | 难度: 在选择题中属于中等难度，需要理解锌闪锌矿晶体结构的基本概念，并能够将紧密堆积的阴离子平面与四面体位置占据情况联系起来。题目要求考生不仅知道晶体结构的基本组成，还需要进行一步逻辑推理（两个四面体位置对应一个阴离子，而每个阴离子对应一个阳离子，因此只有一半位置被占据）。这涉及中等应用层次的知识，包括概念关联和简单计算，但不需要多角度或深度分析。", "convertible": true, "correct_option": "Only one-half of the tetrahedral positions will be occupied because there are two tetrahedral sites per anion, and yet only one cation per anion.", "choice_question": "In the zinc blende crystal structure, which is generated from close-packed planes of anions, what fraction of the positions will be occupied?", "conversion_reason": "The answer is a specific and standard explanation, making it suitable for conversion into a multiple-choice question where the provided answer can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "One-half of the tetrahedral positions", "B": "All of the tetrahedral positions", "C": "One-quarter of the octahedral positions", "D": "Three-quarters of the interstitial sites" }, "correct_answer": "A", "explanation": "The correct answer is A because in zinc blende structure, only half of the tetrahedral positions are occupied by cations while the other half remain empty to maintain charge neutrality. Option B is incorrect as it represents a common overestimation trap where AI might assume full occupancy. Option C exploits confusion between tetrahedral and octahedral sites, while D introduces a mathematically plausible but structurally incorrect fraction to catch AI's tendency towards numerical patterns.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2701, "question": "Given that the vibration frequency of atoms around a vacancy in Cu is 1×10¹³ s⁻¹, ΔEv is 0.15×10⁻¹⁸ J, and exp(ΔSm/k) is approximately 1, calculate the migration frequency of vacancies at 700K.", "answer": "ν=ν₀zexp(−ΔEv/kT)exp(ΔSm/k), ν₇₀₀=1×10¹³×12×exp(−0.15×10⁻¹⁸/(1.38×10⁻²³×700))×1=2.165×10⁷ s⁻¹", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算并应用给定的公式来求解迁移频率，答案是一个具体的计算结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目直接给出了所需的公式和参数，仅需进行简单的代入和计算即可得出答案。虽然涉及指数运算，但整体步骤清晰且直接，无需复杂的推导或多步骤分析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "2.165×10⁷ s⁻¹", "choice_question": "Given that the vibration frequency of atoms around a vacancy in Cu is 1×10¹³ s⁻¹, ΔEv is 0.15×10⁻¹⁸ J, and exp(ΔSm/k) is approximately 1, what is the migration frequency of vacancies at 700K?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.165×10⁷ s⁻¹", "B": "1.082×10⁷ s⁻¹", "C": "4.330×10⁷ s⁻¹", "D": "1.000×10¹³ s⁻¹" }, "correct_answer": "A", "explanation": "正确答案A是通过正确的迁移频率公式计算得出：ν = ν₀ * exp(-ΔEv/kT) = 1×10¹³ * exp(-0.15×10⁻¹⁸/(1.38×10⁻²³*700)) ≈ 2.165×10⁷ s⁻¹。干扰项B是正确答案的一半，利用了简单的数值减半陷阱。干扰项C是正确答案的两倍，利用了数值倍增陷阱。干扰项D直接使用了振动频率ν₀，这是典型的单位混淆陷阱，忽略了指数衰减项的关键影响。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1013, "question": "From the perspective of bonding, analyze the characteristics of ceramic materials", "answer": "Ceramic materials: primarily covalent and ionic bonds, hard, brittle, difficult to deform, high melting point.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求从键合的角度分析陶瓷材料的特性，需要文字解释和论述，答案也是以文字形式呈现的简要论述。 | 知识层次: 题目要求从化学键的角度分析陶瓷材料的特性，需要综合运用化学键理论（共价键和离子键）与材料性能（硬度、脆性、变形能力、熔点）之间的关联，进行推理分析和机理解释。这超出了简单记忆或基本应用的范围，属于复杂分析的层次。 | 难度: 在选择题型中，该题目要求考生从化学键合的角度深入分析陶瓷材料的特性，涉及共价键和离子键的综合理解，以及这些键合类型如何影响材料的硬度、脆性、变形能力和熔点。这需要考生不仅掌握基础概念，还能进行机理层面的解释和推理，属于较高难度的选择题。", "convertible": true, "correct_option": "Ceramic materials: primarily covalent and ionic bonds, hard, brittle, difficult to deform, high melting point.", "choice_question": "From the perspective of bonding, which of the following best describes the characteristics of ceramic materials?", "conversion_reason": "The answer is a standard description of ceramic materials' characteristics, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Primarily covalent and ionic bonds, high hardness, low ductility, excellent thermal stability", "B": "Metallic bonding dominant, moderate hardness, good electrical conductivity, anisotropic properties", "C": "Van der Waals forces predominant, low density, high fracture toughness, variable thermal expansion", "D": "Mixed covalent-metallic bonding, high elastic modulus, excellent creep resistance, isotropic behavior" }, "correct_answer": "A", "explanation": "The correct answer is A because ceramic materials are characterized by strong covalent/ionic bonding which leads to high hardness, brittleness (low ductility), and thermal stability. Option B incorrectly describes metallic materials. Option C describes some polymer characteristics. Option D describes certain advanced composites or intermetallics, not typical ceramics. The distractors exploit: B - confusion with metallic materials, C - misattribution of polymer properties, D - mixing characteristics of different material classes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4564, "question": "What are inhibitors?", "answer": "Inhibitors are substances that, when added to a corrosive environment in relatively low concentrations, decrease the environment's corrosiveness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"inhibitors\"进行文字解释和论述，答案是一个完整的定义性陈述，不需要选择、判断或计算 | 知识层次: 题目考查对抑制剂这一基本概念的定义和简单理解，属于基础概念记忆性知识，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别抑制剂的基本定义，属于最基础的概念记忆层次。题目仅涉及单一概念的简单描述，不需要进行比较分析或复杂推理，因此属于等级1的基本定义简答难度。", "convertible": true, "correct_option": "Inhibitors are substances that, when added to a corrosive environment in relatively low concentrations, decrease the environment's corrosiveness.", "choice_question": "Which of the following best defines inhibitors?", "conversion_reason": "The answer is a standard definition that can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Substances that decrease corrosion rates by forming protective films on metal surfaces", "B": "Materials that increase the activation energy barrier for electrochemical reactions", "C": "Compounds that preferentially adsorb at anodic sites to block dissolution", "D": "Additives that reduce corrosion by consuming dissolved oxygen in the environment" }, "correct_answer": "A", "explanation": "The correct answer A captures the comprehensive mechanism of inhibitors through protective film formation. Option B is a partial truth but describes the effect rather than the definition. Option C is a specific case that only applies to anodic inhibitors. Option D is incorrect as it describes oxygen scavengers rather than inhibitors. Advanced AI might choose B or C due to their technical specificity, missing the broader definition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1255, "question": "What is the direction of diffusion flow from what concentration to what concentration?", "answer": "From high concentration to low concentration", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释扩散流动的方向，答案是一个简短的文字描述而非选择、判断或计算 | 知识层次: 题目考查扩散方向的基本概念记忆，仅需理解从高浓度到低浓度的基本原理，无需复杂分析或应用。 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即扩散流动的方向是从高浓度到低浓度。这属于最基本的知识点掌握，无需复杂的理解或分析步骤，仅需简单回忆定义即可作答。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "From high concentration to low concentration", "choice_question": "What is the direction of diffusion flow?", "conversion_reason": "The answer is a standard concept that can be presented as a choice among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "From regions of high chemical potential to low chemical potential", "B": "From regions of low concentration to high concentration when temperature gradient exists", "C": "Along the direction of decreasing free energy at constant temperature", "D": "Opposite to the direction of increasing entropy in closed systems" }, "correct_answer": "A", "explanation": "The correct answer is A because diffusion fundamentally follows chemical potential gradients, not just concentration gradients (which is a common oversimplification). B exploits the misconception that temperature gradients can reverse normal diffusion. C is a subtle trap - while true for some cases, it's not the most fundamental description. D reverses the actual thermodynamic principle that diffusion increases entropy.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3899, "question": "Calculate the energy of attraction between a cation with a valence of +2 and an anion with a valence of -2 , the centers of which are separated by a distance of 3.7nm.", "answer": "-2.5 × 10^{-19} J", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算离子间的吸引能），需要使用相关公式，且答案以数值形式给出（-2.5 × 10^{-19} J），这些都是计算题的典型特征。 | 知识层次: 题目要求应用库仑定律公式进行简单的数值计算，属于基本公式的直接套用，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需要直接套用库仑定律公式计算离子间的吸引力，属于单一公式直接计算的类型。题目提供了所有必要参数（离子价态、距离），且计算步骤简单，无需复杂的推导或组合多个公式。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "-2.5 × 10^{-19} J", "choice_question": "What is the energy of attraction between a cation with a valence of +2 and an anion with a valence of -2, the centers of which are separated by a distance of 3.7nm?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-2.5 × 10^{-19} J", "B": "-6.2 × 10^{-20} J", "C": "-1.0 × 10^{-18} J", "D": "-3.7 × 10^{-19} J" }, "correct_answer": "A", "explanation": "正确答案A是通过库仑定律精确计算得出的结果。干扰项B错误地使用了原子半径而非离子中心距离进行计算，这是材料科学中常见的概念混淆。干扰项C故意放大了10倍，利用人类对数量级的直觉偏差。干扰项D的数值与题目中给出的距离数值相同但符号错误，这是典型的单位混淆陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 259, "question": "Calculate the diffusion coefficient of carbon in α-Fe (body-centered cubic), given the diffusion coefficient formula as D=0.0079exp[-83600/RT] cm²/s, temperature T=800°C (1073K), and gas constant R=8.314 J/(mol·K).", "answer": "Substitute T=1073K into the formula D=0.0079exp[-83600/(8.314×1073)] cm²/s, and calculate to obtain D_α=6.7×10^-7 cm²/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出扩散系数的具体数值。答案展示了具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目主要涉及直接套用给定的扩散系数公式进行数值计算，无需多步推理或综合分析，属于基本公式应用和简单计算范畴。 | 难度: 在选择题型中，该题目仅需要直接套用给定的扩散系数公式，并进行简单的数值计算。解题步骤非常直接，不涉及多个公式的组合或复杂的概念理解，因此属于单一公式直接计算的难度等级1。", "convertible": true, "correct_option": "6.7×10^-7 cm²/s", "choice_question": "Calculate the diffusion coefficient of carbon in α-Fe (body-centered cubic), given the diffusion coefficient formula as D=0.0079exp[-83600/RT] cm²/s, temperature T=800°C (1073K), and gas constant R=8.314 J/(mol·K). The diffusion coefficient is:", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.7×10^-7 cm²/s", "B": "3.2×10^-6 cm²/s", "C": "1.1×10^-8 cm²/s", "D": "4.5×10^-5 cm²/s" }, "correct_answer": "A", "explanation": "The correct answer is calculated by substituting the given values into the diffusion coefficient formula D=0.0079exp[-83600/RT]. Option B is a common error where the temperature is not converted from °C to K. Option C results from incorrectly using the activation energy in kJ/mol instead of J/mol. Option D is a trap for those who misapply the formula for γ-Fe (FCC) diffusion coefficients, which are typically higher than in α-Fe (BCC).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3405, "question": "Explain the meaning of the steel grade 4Cr13", "answer": "4Cr13 is a martensitic stainless steel, wc=0.4%, w=13%", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释钢号4Cr13的含义，答案提供了文字解释和论述，符合简答题的特征 | 知识层次: 题目考查对钢材牌号的基本概念记忆和理解，需要解释牌号中各元素的含义及其含量，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求记忆基本的钢号命名规则和成分含义，属于基础概念记忆层次。正确选项直接给出了钢号4Cr13的碳含量和铬含量，无需复杂分析或推理，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "4Cr13 is a martensitic stainless steel, wc=0.4%, w=13%", "choice_question": "Which of the following correctly describes the steel grade 4Cr13?", "conversion_reason": "The answer is a standard description of the steel grade, which can be presented as a correct option among other plausible but incorrect descriptions.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4Cr13 is a martensitic stainless steel with 0.4% carbon and 13% chromium", "B": "4Cr13 is an austenitic stainless steel with 4% chromium and 13% nickel", "C": "4Cr13 is a ferritic stainless steel with 4% carbon and 13% chromium", "D": "4Cr13 is a duplex stainless steel with 0.4% chromium and 13% carbon" }, "correct_answer": "A", "explanation": "The correct answer is A because 4Cr13 follows the Chinese steel grade nomenclature where the first number represents carbon content in 0.1% units (0.4% here) and Cr13 indicates 13% chromium, forming a martensitic structure. Option B is wrong by switching to austenitic and adding nickel which isn't in the grade. Option C incorrectly makes it ferritic and misinterprets the carbon content. Option D reverses the carbon/chromium percentages and incorrectly classifies it as duplex steel.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 52, "question": "What are the structural characteristics of chain silicates?", "answer": "The structural characteristics of chain silicates: [Si04] shares 2 or 3 O2-, shapes include single chains and double chains, the complex anion groups are [Si206]4 and [Si40], with Si:O ratios of 1:3 and 4:11 respectively.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释链状硅酸盐的结构特征，答案提供了详细的文字描述和论述，符合简答题的特点。 | 知识层次: 题目考查对链状硅酸盐结构特征的基本概念记忆和理解，包括其组成单元、形状和比例等基础知识点，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个结构特征（如[Si04]共享氧离子、单链和双链形状、复杂阴离子基团及其Si:O比例），但这些都属于基础概念记忆范畴。选择题型允许通过选项提示来辅助回忆，降低了纯记忆的难度。但题目要求同时掌握多个相关特征，比单纯记忆单一定义（等级1）要复杂，因此属于等级2。", "convertible": true, "correct_option": "The structural characteristics of chain silicates: [Si04] shares 2 or 3 O2-, shapes include single chains and double chains, the complex anion groups are [Si206]4 and [Si40], with Si:O ratios of 1:3 and 4:11 respectively.", "choice_question": "Which of the following describes the structural characteristics of chain silicates?", "conversion_reason": "The answer is a standard description of the structural characteristics of chain silicates, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Chain silicates consist of [SiO4] tetrahedra sharing 2 or 3 oxygen atoms, forming single chains ([Si2O6]4-) or double chains ([Si4O11]6-) with Si:O ratios of 1:3 and 4:11 respectively", "B": "Chain silicates are built from [SiO4] tetrahedra sharing all 4 oxygen atoms, creating infinite chains with a fixed Si:O ratio of 1:4", "C": "Chain silicates feature alternating [SiO4] and [AlO4] tetrahedra sharing 3 oxygen atoms, resulting in a variable Si:O ratio between 1:2.5 and 1:3", "D": "Chain silicates contain isolated [SiO4] tetrahedra linked by metal cations, maintaining a strict 1:4 Si:O ratio throughout the structure" }, "correct_answer": "A", "explanation": "Correct answer A accurately describes chain silicates' key characteristics: oxygen sharing between tetrahedra, chain types, and correct Si:O ratios. Option B is wrong but tempting as it suggests complete oxygen sharing which seems plausible for 'chain' structures. Option C exploits the common Al-Si substitution in silicates but incorrectly applies it here. Option D describes nesosilicates (isolated tetrahedra) which beginners might confuse with chain silicates due to similar building blocks.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2017, "question": "The maximum solid solubility (mole fraction) of nitrogen in γ-Fe is x_N=10.3×10^-2. Given that N atoms occupy octahedral interstitial sites, calculate the percentage of octahedral interstitial sites occupied by N atoms.", "answer": "The percentage of octahedral interstitial sites occupied by N atoms is 12.5%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算氮原子占据八面体间隙的百分比），并给出了具体的数值和公式应用（最大固溶度和间隙位置信息）。答案也是一个具体的数值结果。 | 知识层次: 题目需要应用给定的最大固溶度数据，结合晶体结构中八面体间隙位置的基本知识，进行简单的百分比计算。虽然涉及晶体结构的概念，但计算过程直接且无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目仅需应用给定的最大固溶度（mole fraction）数据，并直接计算占据八面体间隙位置的氮原子百分比。解题步骤简单直接，无需多个公式组合或复杂分析，符合等级1的标准。", "convertible": true, "correct_option": "12.5%", "choice_question": "The maximum solid solubility (mole fraction) of nitrogen in γ-Fe is x_N=10.3×10^-2. Given that N atoms occupy octahedral interstitial sites, what is the percentage of octahedral interstitial sites occupied by N atoms?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format with the correct option being the provided answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "12.5%", "B": "10.3%", "C": "20.6%", "D": "5.15%" }, "correct_answer": "A", "explanation": "The correct answer is A (12.5%) because γ-Fe has 1 octahedral interstitial site per Fe atom. With x_N=10.3×10^-2, the occupancy percentage is calculated as (x_N)/(1-x_N)×100% = (0.103/0.897)×100% ≈ 12.5%. Option B (10.3%) is a direct trap using the mole fraction without considering site ratio. Option C (20.6%) doubles the mole fraction, exploiting a common calculation error. Option D (5.15%) halves the mole fraction, targeting unit conversion errors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2507, "question": "Why do the properties of elements change periodically with atomic number?", "answer": "Because the properties of elements are mainly determined by the number of outer valence electrons, and the number of valence electrons changes periodically with atomic number, thus reflecting the periodic changes in the properties of elements.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释元素性质随原子序数周期性变化的原因，答案需要文字解释和论述，符合简答题的特征 | 知识层次: 题目考查对元素性质周期性变化的基本原理的理解和记忆，主要涉及外层价电子数与原子序数的关系这一基础概念，不需要复杂的推理或综合分析。 | 难度: 该题目在选择题型中属于中等难度。虽然题目涉及基础概念记忆，但需要理解元素性质周期性变化的原因，并能够将原子序数与价电子数的周期性变化联系起来。正确选项不仅要求记忆基本原理，还需要进行简单的概念解释和描述，因此难度高于基本定义简答的等级1，但尚未达到复杂概念体系阐述的等级3。", "convertible": true, "correct_option": "Because the properties of elements are mainly determined by the number of outer valence electrons, and the number of valence electrons changes periodically with atomic number, thus reflecting the periodic changes in the properties of elements.", "choice_question": "Why do the properties of elements change periodically with atomic number?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question. The question can be kept as is or slightly rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because the properties of elements are mainly determined by the number of outer valence electrons, and the number of valence electrons changes periodically with atomic number, thus reflecting the periodic changes in the properties of elements.", "B": "Because the atomic radius decreases monotonically with increasing atomic number, causing periodic changes in chemical reactivity.", "C": "Because the nuclear charge increases linearly with atomic number, creating periodic variations in electron shielding effects.", "D": "Because the electron configuration follows Hund's rule, which leads to periodic filling of electron orbitals." }, "correct_answer": "A", "explanation": "The correct answer is A because the periodic properties of elements are fundamentally determined by their valence electron configuration, which repeats periodically as atomic number increases. Option B is incorrect because atomic radius does not decrease monotonically - it shows periodic trends. Option C is partially correct but misleading as it ignores the crucial role of valence electrons. Option D misapplies Hund's rule, which governs electron filling within a subshell, not the overall periodic pattern.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2397, "question": "A simple cubic crystal has a screw dislocation with $b=[001]$ on the (100) plane. An edge dislocation with $b=[010]$ on the (001) plane intersects with it. After the intersection, do kinks or jogs form on the two dislocations?", "answer": "After the intersection of the two dislocations, a small segment of dislocation with the same magnitude and direction as the Burgers vector of the other dislocation is left on each dislocation. If this small segment lies on the slip plane of the original dislocation, it is a kink; otherwise, it is a jog. Let dislocation A be the screw dislocation with $b=[001]$ on the (100) plane, and dislocation B be the edge dislocation with $b=[010]$ on the (001) plane. After the intersection of dislocation A and dislocation B, dislocation A produces a small segment of dislocation in the [010] direction. The slip plane of dislocation A is (100), and [010]·[100]=0, meaning the small segment lies on the slip plane of dislocation A, so it is a kink. On dislocation B, a small segment of dislocation in the [001] direction is produced. The slip plane of dislocation B is (001), and [001]·[001]=1, meaning the small segment does not lie on the slip plane of dislocation B, so it is a jog.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来分析位错相交后形成的结构类型（kink或jog），需要详细说明判断依据和过程，属于需要文字解释的简答题类型。 | 知识层次: 题目涉及位错交互作用的复杂分析，需要理解位错的性质（如螺位错和刃位错）、柏氏矢量的方向、滑移面的确定，以及kink和jog的形成机制。解答过程需要综合运用这些概念进行推理和分析，判断位错交互后形成的缺陷类型，属于较高层次的认知能力要求。 | 难度: 在选择题型内，该题目属于最高难度等级。题目涉及复杂的位错相互作用分析，要求考生不仅掌握位错的基本概念（如螺位错、刃位错、伯格斯矢量、滑移面等），还需要深入理解位错相交后形成的kink和jog的机理。解题过程中需要综合运用向量点积判断位错段是否在滑移面上，并进行多步逻辑推理。这种题目在选择题型中属于对知识深度和综合分析能力要求极高的类型，需要考生具备扎实的理论基础和较强的空间想象能力。", "convertible": true, "correct_option": "A kink forms on the screw dislocation and a jog forms on the edge dislocation.", "choice_question": "A simple cubic crystal has a screw dislocation with $b=[001]$ on the (100) plane. An edge dislocation with $b=[010]$ on the (001) plane intersects with it. After the intersection, what forms on the two dislocations?", "conversion_reason": "The answer is a standard explanation involving the concepts of kinks and jogs in dislocation theory, which can be succinctly summarized into a single correct option for a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A kink forms on the screw dislocation and a jog forms on the edge dislocation", "B": "A jog forms on both dislocations", "C": "A kink forms on both dislocations", "D": "The dislocations annihilate each other" }, "correct_answer": "A", "explanation": "The correct answer is A because when a screw and edge dislocation intersect, the screw dislocation acquires a kink (short segment of edge character) and the edge dislocation acquires a jog (short segment of screw character). Option B is incorrect because it ignores the different responses of screw vs edge dislocations. Option C is wrong as it fails to recognize the jog formation mechanism. Option D is a common misconception trap, as dislocations with perpendicular Burgers vectors cannot annihilate.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1744, "question": "In the non-stoichiometric compound ZrO2-x, the lattice defect present is a. anion vacancy b. cation vacancy c. anion interstitial d. cation interstitial", "answer": "a", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查非化学计量化合物中晶格缺陷类型的基本概念记忆，仅需识别ZrO2-x中存在的缺陷类型（阴离子空位），无需复杂分析或计算。 | 难度: 在选择题型中，该题目需要理解非化学计量化合物ZrO2-x中的晶格缺陷类型，并能够区分阴离子空位、阳离子空位、阴离子间隙和阳离子间隙等概念。虽然题目涉及基础概念记忆，但需要一定的概念理解和简单辨析能力，因此属于等级2难度。", "convertible": true, "correct_option": "a. anion vacancy", "choice_question": "In the non-stoichiometric compound ZrO2-x, the lattice defect present is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Schottky defects dominate at temperatures below 0.5Tm", "B": "Frenkel defects require cation-anion size mismatch", "C": "Dislocation climb is the primary mechanism for high-temperature creep", "D": "Grain boundary diffusion has higher activation energy than lattice diffusion" }, "correct_answer": "C", "explanation": "Correct answer is C because dislocation climb is indeed the dominant mechanism for high-temperature creep in crystalline materials. A is incorrect (but tempting) because Schottky defects actually become significant near melting temperature (Tm). B is a cognitive trap - while size mismatch facilitates Frenkel defects, it's not an absolute requirement. D reverses the actual relationship between grain boundary and lattice diffusion activation energies, exploiting a common misconception.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2516, "question": "Explain the term: component", "answer": "Each element (metal, non-metal) that constitutes an alloy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释术语\"component\"，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即对“component”这一术语的定义进行解释，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求识别\"component\"的基本定义（合金的构成元素），属于最基础的概念记忆层面。正确选项直接给出了术语的明确定义，不需要任何解释、比较或推理过程，完全符合等级1\"基本定义简答\"的标准。这类题目只需考生记住最基础的专业术语定义即可作答。", "convertible": true, "correct_option": "Each element (metal, non-metal) that constitutes an alloy.", "choice_question": "Which of the following best defines the term 'component'?", "conversion_reason": "The answer is a standard definition of the term 'component', which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Each element (metal, non-metal) that constitutes an alloy", "B": "The smallest structural unit that retains the properties of a material", "C": "The ratio of different phases present in a microstructure", "D": "Any constituent that can be mechanically separated from a composite" }, "correct_answer": "A", "explanation": "The correct answer is A because in materials science, 'component' specifically refers to the distinct chemical elements that make up an alloy or mixture. Option B incorrectly describes a unit cell in crystallography. Option C confuses components with phase fractions, a common misconception. Option D is a plausible but incorrect definition that applies to composites rather than alloy systems, exploiting the AI's tendency to generalize definitions across material classes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4652, "question": "What type(s) of bonding would be expected for rubber?\n(A) Ionic bonding\n(B) Metallic bonding\n(C) Covalent bonding with some van der Waals bonding\n(D) van der Waals bonding", "answer": "FE}\nThe correct answer is C. For rubber, the bonding is covalent with some van der Waals bonding. (Rubber is composed primarily of carbon and hydrogen atoms.)", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案，提供了四个选项（A-D），并给出了正确答案C。这是典型的选择题形式。 | 知识层次: 题目考查对橡胶材料键合类型的基本概念记忆和理解，属于基础知识点，无需复杂分析或计算。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要理解橡胶的化学键类型（共价键和范德华力），但选项之间的区分较为明显，不需要复杂的分析过程。学生只需掌握基本的材料键合类型知识即可正确作答。", "convertible": true, "correct_option": "Covalent bonding with some van der Waals bonding", "choice_question": "What type(s) of bonding would be expected for rubber?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ionic bonding", "B": "Metallic bonding", "C": "Covalent bonding with some van der Waals bonding", "D": "van der Waals bonding" }, "correct_answer": "C", "explanation": "Rubber is a polymer composed of long chains of carbon atoms with covalent bonds within the chains. The weak interactions between the chains are van der Waals forces. Option A (Ionic bonding) is incorrect but may seem plausible due to the presence of polar groups in some rubbers. Option B (Metallic bonding) is a strong distractor as it plays on the misconception that elasticity implies metallic behavior. Option D (van der Waals bonding) is partially correct but ignores the primary covalent bonding within the polymer chains.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 739, "question": "The essence of crystals", "answer": "is the periodic repetition of particles in three-dimensional space", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对晶体的本质进行文字解释和论述，答案是一个简短的文字描述，符合简答题的特征。 | 知识层次: 题目考查晶体本质的基本概念记忆和理解，仅需回答周期性重复排列的定义，不涉及应用或分析。 | 难度: 在选择题型中，该题目仅考察对晶体本质的基础定义记忆，属于最基础的概念性知识。正确选项直接给出了晶体的周期性重复特征，无需任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "is the periodic repetition of particles in three-dimensional space", "choice_question": "The essence of crystals is:", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The periodic repetition of particles in three-dimensional space", "B": "The presence of long-range atomic order and sharp diffraction peaks", "C": "The existence of a well-defined unit cell with translational symmetry", "D": "The minimum energy configuration of atoms in a solid state" }, "correct_answer": "A", "explanation": "The correct answer is A because the fundamental essence of crystals lies in their periodic arrangement of particles in 3D space, which is the most universal definition encompassing all crystal types. Option B is a cognitive bias trap - while true for most crystals, some disordered crystals can exhibit diffuse scattering. Option C exploits professional intuition by focusing on unit cells, but quasicrystals violate this condition while still being crystalline. Option D is a multi-level verification trap - while crystals often represent low-energy configurations, amorphous solids can also achieve local energy minima without periodicity.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4436, "question": "(b) Suppose that CaCl2 is added as an impurity to CaO. If the Cl substitutes for O2-, what kind of vacancies would you expect to form? How many of the vacancies are created for every Cl- added?", "answer": "calcium vacancies. Two Cl- ions will lead to the formation of one calcium vacancy.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释和论述CaCl2作为杂质添加到CaO中时，Cl-取代O2-会形成何种空位以及每添加一个Cl-会形成多少个空位。答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目需要理解杂质掺杂对晶体缺陷的影响，并分析Cl-取代O2-时电荷平衡的机制，涉及多步推理和概念关联。虽然不涉及复杂计算，但需要综合分析电荷补偿和缺陷形成的原理。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及杂质掺杂和空位形成的机制，要求考生掌握离子替代对晶体缺陷的影响，并能进行简单的化学计量关系计算。虽然解题步骤相对明确，但需要将多个概念（如离子半径、电荷平衡、空位形成）关联起来综合分析，符合等级3的综合分析和说明要求。", "convertible": true, "correct_option": "calcium vacancies. Two Cl- ions will lead to the formation of one calcium vacancy.", "choice_question": "Suppose that CaCl2 is added as an impurity to CaO. If the Cl substitutes for O2-, what kind of vacancies would you expect to form and how many of the vacancies are created for every Cl- added?", "conversion_reason": "The answer is a standard terminology and concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "oxygen vacancies; one vacancy per two Cl- ions", "B": "calcium vacancies; one vacancy per Cl- ion", "C": "oxygen vacancies; two vacancies per Cl- ion", "D": "calcium vacancies; one vacancy per two Cl- ions" }, "correct_answer": "D", "explanation": "The correct answer is D because when Cl- substitutes for O2- in CaO, the charge imbalance is compensated by creating calcium vacancies. Each Cl- introduces half a positive charge imbalance, so two Cl- substitutions require one calcium vacancy to maintain charge neutrality. Option A incorrectly suggests oxygen vacancies would form. Option B overestimates the vacancy creation rate. Option C combines both the wrong vacancy type and incorrect stoichiometry.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4479, "question": "Compute repeat unit molecular weight for polydimethylsiloxane", "answer": "74.16g/mol", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算聚二甲基硅氧烷的重复单元分子量，需要通过数值计算和公式应用得出具体数值结果74.16g/mol，符合计算题的特征。 | 知识层次: 题目要求计算聚二甲基硅氧烷的重复单元分子量，这属于基本公式应用和简单计算，只需理解重复单元的结构并应用原子量进行加和即可，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目仅需直接套用单一公式（重复单元分子量计算）即可得出答案，无需复杂推导或多步骤计算。题目明确给出了重复单元结构（聚二甲基硅氧烷），且计算过程仅涉及基本原子量相加，属于最基础的应用层级。", "convertible": true, "correct_option": "74.16g/mol", "choice_question": "What is the repeat unit molecular weight for polydimethylsiloxane?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "74.16 g/mol", "B": "162.38 g/mol", "C": "58.08 g/mol", "D": "92.18 g/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (74.16 g/mol) which is calculated by summing the atomic weights of the repeat unit (Si: 28.09, O: 16.00, C: 12.01, H: 1.01). Option B (162.38 g/mol) is a trap for those who mistakenly include two repeat units. Option C (58.08 g/mol) exploits the common error of omitting the oxygen atoms. Option D (92.18 g/mol) is designed to catch those who incorrectly include terminal methyl groups in the calculation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3660, "question": "Suppose one Schottky defect is present in every tenth unit cell of MgO. MgO has the sodium chloride crystal structure and a lattice parameter of 0.396 nm. Calculate the number of anion vacancies per cm3.", "answer": "1.61 × 10^21 vacancies/cm^3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算每立方厘米的阴离子空位数），需要应用公式和单位转换，最终答案为具体数值（1.61 × 10^21 vacancies/cm^3），符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括计算单位晶胞体积、确定缺陷密度，并最终转换为每立方厘米的缺陷数。这需要理解Schottky缺陷的概念、晶格参数的应用以及单位转换的综合能力。虽然不涉及复杂的推理或机理解释，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及Schottky缺陷的概念、晶格参数的计算以及单位转换，解题步骤包括计算单位晶胞体积、确定缺陷密度以及转换为每立方厘米的缺陷数。虽然计算步骤较多，但在选择题型中，正确选项的提示可以帮助考生验证计算过程，因此难度适中。", "convertible": true, "correct_option": "1.61 × 10^21 vacancies/cm^3", "choice_question": "Suppose one Schottky defect is present in every tenth unit cell of MgO. MgO has the sodium chloride crystal structure and a lattice parameter of 0.396 nm. The number of anion vacancies per cm3 is:", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice question format by presenting the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.61 × 10^21 vacancies/cm^3", "B": "3.22 × 10^21 vacancies/cm^3", "C": "8.05 × 10^20 vacancies/cm^3", "D": "4.03 × 10^20 vacancies/cm^3" }, "correct_answer": "A", "explanation": "The correct answer is A because: 1) Calculate unit cell volume (0.396 nm)^3 = 6.21 × 10^-23 cm^3. 2) With one defect per 10 unit cells, vacancy concentration is 1/(10×6.21×10^-23) = 1.61×10^21 cm^-3. Option B is a cognitive bias trap - it doubles the correct value by incorrectly counting both cation and anion vacancies. Option C is a unit conversion trap - it uses half the lattice parameter (0.198 nm) in calculation. Option D is a structure factor trap - it divides by 4 assuming wrong coordination number.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 490, "question": "Polymers with simple structures, high regularity, and good symmetry are prone to crystallization.", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对聚合物结晶基本原理的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基本概念正误判断。题目仅涉及聚合物结晶的基本原理，即结构简单、规则性高和对称性好的聚合物易于结晶这一基础概念的陈述。正确选项为√，表明这是一个直接的记忆性知识判断，无需复杂的分析或推理。因此，在选择题型内，该题目属于最低难度等级。", "convertible": true, "correct_option": "√", "choice_question": "Polymers with simple structures, high regularity, and good symmetry are prone to crystallization.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous polymers will crystallize when cooled below their glass transition temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This is false because amorphous polymers lack the molecular regularity required for crystallization, regardless of temperature. The statement contains an absolute claim ('all') that is incorrect. Some polymers may develop limited local order, but true crystallization requires structural regularity. This traps students who may confuse Tg with crystallization temperature or assume all polymers can crystallize under the right conditions.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4369, "question": "What is one important difference between continuous cooling transformation diagrams for plain carbon and alloy steels regarding the position of the pearlite-proeutectoid noses?", "answer": "The pearlite-proeutectoid noses for plain carbon steel alloys are positioned at shorter times than for the alloy steels.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释连续冷却转变图中普通碳钢和合金钢在珠光体-先共析体鼻部位置的重要差异，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求比较两种不同钢种的连续冷却转变图中珠光体-先共析鼻的位置差异，需要理解并应用相关概念，涉及多步分析和概念关联，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解连续冷却转变图的基本概念，并能比较分析普通碳钢和合金钢在珠光体-先共析体鼻部位置上的差异。虽然题目涉及多步计算和概念关联，但在选择题型中，通过正确选项可以直接判断答案，不需要进行深度关联性分析或多角度论述。", "convertible": true, "correct_option": "The pearlite-proeutectoid noses for plain carbon steel alloys are positioned at shorter times than for the alloy steels.", "choice_question": "What is one important difference between continuous cooling transformation diagrams for plain carbon and alloy steels regarding the position of the pearlite-proeutectoid noses?", "conversion_reason": "The answer is a standard statement that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The pearlite-proeutectoid noses for plain carbon steel alloys are positioned at shorter times than for the alloy steels", "B": "The pearlite-proeutectoid noses for alloy steels are positioned at higher temperatures than for plain carbon steels", "C": "Plain carbon steels show a single nose while alloy steels show double noses in their CCT diagrams", "D": "The nose positions are identical but the transformation kinetics differ due to carbon diffusion rates" }, "correct_answer": "A", "explanation": "Correct answer A reflects the key difference that alloying elements shift the CCT curves to longer times. Option B is a temperature-based distraction playing on the misconception that alloying affects transformation temperatures more than times. Option C exploits the visual similarity with TTT diagrams where some alloys show double noses. Option D uses a partially correct statement about diffusion rates to mask the critical time difference.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2171, "question": "For annealed pure iron with a grain size of $N_{\\\\mathrm{A}}=16$ grains/mm², its yield strength $\\\\sigma_{\\\\textrm{s}}=100$ MPa; when $N_{\\\\mathrm{A}}=4~096$ grains/mm², $\\\\sigma_{\\\\mathrm{s}}=250\\\\mathrm{MPa}$. Calculate $\\\\sigma_{s}$ when $N_{\\\\mathrm{A}}=250$ grains/mm².", "answer": "Let the average grain diameter be $d$, and the number of grains per square millimeter be $N_{\\\\mathrm{A}}$. It can be proven that $$ d=\\\\sqrt{\\\\frac{8}{3\\\\pi N_{\\\\mathrm{A}}}} $$ Therefore, $$ d_{1}=\\\\sqrt{\\\\frac{8}{3\\\\pi\\\\times16}}=0.053\\\\mathrm{~mm} $$ $$ d_{2}=\\\\sqrt{\\\\frac{8}{3\\\\pi\\\\times4~096}}=2.072\\\\times10^{-4}~\\\\mathrm{mm} $$ $$ d_{3}=\\\\sqrt{\\\\frac{8}{3\\\\pi\\\\times250}}=3.395\\\\times10^{-3}\\\\mathrm{mm} $$ Substituting into the Hall-Petch formula, $$ \\\\begin{array}{l}{\\\\left\\\\{100=\\\\sigma_{0}+K(0.053)^{-1/2}\\\\right.} \\\\\\\\ {\\\\left.250=\\\\sigma_{0}+K(2.072\\\\times10^{-4})^{-1/2}\\\\right.}\\\\end{array} $$ Solving gives $$ \\\\sigma_{0}=90\\\\mathrm{MPa} $$ Therefore, when $N_{\\\\mathrm{A}}=250$ grains/mm² and $d=3.395\\\\times10^{-3}\\\\mathrm{mm}$, $$ \\\\sigma_{\\\\mathrm{s}}=90+2.303\\\\times(3.395\\\\times10^{-3})^{-1/2}=129.5~\\\\mathrm{MPa} $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用（Hall-Petch公式）来求解特定条件下的屈服强度，答案包含详细的数学推导和计算结果。 | 知识层次: 题目需要应用Hall-Petch公式进行多步计算，涉及不同晶粒尺寸下的屈服强度计算，需要理解公式中各参数的含义并进行数值求解。虽然不涉及复杂的机理分析或创新应用，但需要一定的综合分析能力和计算技巧。 | 难度: 在选择题中属于中等偏上难度，需要理解Hall-Petch公式并正确应用，涉及多步计算和变量求解。虽然题目提供了部分计算过程，但需要考生掌握晶粒尺寸与屈服强度的关系，并能正确代入公式求解。此外，还需要解二元一次方程组来求得材料常数，最后再进行一次公式应用计算目标值。这些步骤在选择题型中属于较为复杂的计算过程。", "convertible": true, "correct_option": "129.5 MPa", "choice_question": "For annealed pure iron with a grain size of $N_{\\mathrm{A}}=250$ grains/mm², calculate its yield strength $\\sigma_{\\mathrm{s}}$ based on the given data: when $N_{\\mathrm{A}}=16$ grains/mm², $\\sigma_{\\textrm{s}}=100$ MPa; when $N_{\\mathrm{A}}=4~096$ grains/mm², $\\sigma_{\\mathrm{s}}=250\\mathrm{MPa}$.", "conversion_reason": "The calculation yields a specific numerical answer (129.5 MPa), which can be presented as one of the options in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "129.5 MPa", "B": "175.2 MPa", "C": "89.3 MPa", "D": "210.6 MPa" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Hall-Petch relationship (σ_s = σ_0 + k/√d), where grain size (d) is inversely proportional to N_A. The linear relationship between √N_A and σ_s gives σ_s = 129.5 MPa for N_A=250. Option B incorrectly assumes a direct proportionality between N_A and σ_s. Option C reverses the relationship direction. Option D uses an invalid power-law extrapolation from the given data points.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1415, "question": "Will ceramic materials exhibit 'work hardening' after deformation? Please briefly explain.", "answer": "Ceramic materials will not exhibit 'work hardening' after deformation, because ceramic materials cannot undergo plastic deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对陶瓷材料是否表现出“加工硬化”进行简要解释，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对陶瓷材料变形行为的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅要求考生记忆并识别陶瓷材料的基本特性（无法塑性变形），不需要进行概念解释或复杂分析。正确选项直接给出了定义性结论，属于最基础的概念记忆层次。", "convertible": true, "correct_option": "Ceramic materials will not exhibit 'work hardening' after deformation, because ceramic materials cannot undergo plastic deformation.", "choice_question": "Which of the following statements about ceramic materials and 'work hardening' is correct?", "conversion_reason": "The original short answer question can be converted into a multiple-choice question by presenting the correct answer as one of the options and rephrasing the question to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ceramic materials will not exhibit 'work hardening' after deformation, because ceramic materials cannot undergo plastic deformation.", "B": "Ceramic materials can exhibit work hardening similar to metals, as both materials experience dislocation movement during deformation.", "C": "Work hardening in ceramics occurs only at extremely high temperatures (>0.8Tm) where limited plastic deformation becomes possible.", "D": "Ceramics show work hardening through a different mechanism involving crack deflection and grain boundary sliding rather than dislocation motion." }, "correct_answer": "A", "explanation": "The correct answer is A because ceramics are inherently brittle materials that fracture before plastic deformation can occur, making work hardening impossible. Option B is a cognitive bias trap, exploiting the common knowledge that metals work harden through dislocations. Option C is a professional intuition trap, using the partial truth about high-temperature ceramic deformation but ignoring that this still doesn't produce conventional work hardening. Option D is a multi-level verification trap, combining real ceramic deformation mechanisms (crack deflection) with an incorrect application to work hardening.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4525, "question": "(a) What is the distinction between cement and concrete?", "answer": "Concrete consists of an aggregate of particles that are bonded together by a cement.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释水泥和混凝土之间的区别，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查基础概念的记忆和理解，即水泥和混凝土的区别，属于定义性的知识。 | 难度: 在选择题型中，此题仅需要识别和区分两个基础材料科学概念（水泥和混凝土）的定义关系。正确选项直接给出了明确的定义对比，属于最基础的概念记忆层次，不需要复杂的分析或推理过程。", "convertible": true, "correct_option": "Concrete consists of an aggregate of particles that are bonded together by a cement.", "choice_question": "What is the distinction between cement and concrete?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Concrete consists of an aggregate of particles that are bonded together by a cement", "B": "Cement is a composite material while concrete is a pure ceramic compound", "C": "Concrete is the precursor material that hardens to form cement", "D": "Cement contains reinforcement fibers while concrete does not" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines the relationship where cement acts as the binding agent in concrete. Option B reverses the composite nature (concrete is the composite). Option C inverts the actual material hierarchy. Option D introduces a false distinction about reinforcement that applies to reinforced concrete, not basic cement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1244, "question": "According to the phase rule, what is the degree of freedom when the number of equilibrium phases in a binary system is at its maximum?", "answer": "18", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求根据相律计算二元系统中平衡相数最大时的自由度，需要应用公式进行数值计算，答案是一个具体的数值(18)，符合计算题的特征。 | 知识层次: 题目考查相律公式的直接应用，仅需将二元系统的最大平衡相数代入公式进行简单计算，无需多步推理或综合分析。 | 难度: 在选择题型中，该题目属于最简单难度等级。题目直接考察对相律公式（F = C - P + 2）的简单套用，在二元系统中最大平衡相数时（P=3），只需将数值代入公式即可得出自由度F=1。不需要任何额外的推导或复杂计算，完全符合等级1\"单一公式直接计算\"的标准。", "convertible": true, "correct_option": "0", "choice_question": "According to the phase rule, what is the degree of freedom when the number of equilibrium phases in a binary system is at its maximum?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项B", "B": "选项D", "C": "0", "D": "选项C" }, "correct_answer": "C", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1298, "question": "Why do solid solution alloys usually grow in a dendritic manner during solidification under a positive temperature gradient?", "answer": "During the crystallization of solid solutions, constitutional supercooling occurs, leading to a constitutionally supercooled zone ahead of the solid-liquid interface. If any small protrusion exists on the interface, it will extend into the constitutionally supercooled zone and continue to grow as it gains supercooling. Therefore, the interface cannot remain flat and stable, resulting in dendritic growth.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么固溶体合金在正温度梯度下凝固时通常以枝晶方式生长，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要解释固溶体合金在正温度梯度下凝固时形成枝晶的原因，涉及成分过冷、固液界面稳定性等概念的关联和综合分析，需要深入理解凝固过程中的热力学和动力学机制，并进行推理分析。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "During the crystallization of solid solutions, constitutional supercooling occurs, leading to a constitutionally supercooled zone ahead of the solid-liquid interface. If any small protrusion exists on the interface, it will extend into the constitutionally supercooled zone and continue to grow as it gains supercooling. Therefore, the interface cannot remain flat and stable, resulting in dendritic growth.", "choice_question": "Why do solid solution alloys usually grow in a dendritic manner during solidification under a positive temperature gradient?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Constitutional supercooling creates an unstable interface that promotes dendritic growth", "B": "Rapid heat extraction causes spontaneous branching of crystal facets", "C": "Solute partitioning reduces interfacial energy anisotropy below critical levels", "D": "Positive temperature gradients inherently favor faceted growth morphologies" }, "correct_answer": "A", "explanation": "Correct answer A describes the actual constitutional supercooling mechanism. B exploits the common misconception that rapid cooling alone causes dendrites (while ignoring solute effects). C uses accurate terminology ('solute partitioning') but falsely applies it to interfacial energy. D reverses the actual relationship between temperature gradients and growth morphology.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 936, "question": "What is the main difference between nucleation and growth during solidification and nucleation and growth during recrystallization?", "answer": "The driving force for nucleation and growth during solidification is the chemical potential difference between the new and old phases, while the driving force for nucleation and growth during recrystallization is solely the stored deformation energy. Nucleation during solidification is often homogeneous; nucleation during recrystallization typically occurs in existing regions of deformation inhomogeneity, such as near grain boundaries, shear bands, deformation bands, or around second-phase particles. During solidification growth, there is no orientation relationship with the parent phase, whereas during recrystallization growth, there may be a certain orientation relationship.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释和论述两种过程中成核和生长的主要区别，答案提供了详细的文字解释，没有涉及选择、判断或计算。 | 知识层次: 题目要求比较两种不同过程中成核和生长的差异，涉及多个概念的综合运用和机理的解释，需要深入理解固化和再结晶的驱动机制、成核位置以及生长过程中的取向关系等复杂因素。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解固化和再结晶过程中的成核与生长机制，还需要深入比较两者的驱动力差异、成核位置差异以及生长过程中的取向关系差异。这需要综合运用材料科学中的相变理论、变形储能概念以及微观结构演化知识，进行复杂的推理分析和机理解释。选择题型中此类综合比较题目对知识深度和逻辑分析能力要求极高，因此属于最高难度等级。", "convertible": true, "correct_option": "The driving force for nucleation and growth during solidification is the chemical potential difference between the new and old phases, while the driving force for nucleation and growth during recrystallization is solely the stored deformation energy. Nucleation during solidification is often homogeneous; nucleation during recrystallization typically occurs in existing regions of deformation inhomogeneity, such as near grain boundaries, shear bands, deformation bands, or around second-phase particles. During solidification growth, there is no orientation relationship with the parent phase, whereas during recrystallization growth, there may be a certain orientation relationship.", "choice_question": "What is the main difference between nucleation and growth during solidification and nucleation and growth during recrystallization?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The driving force for both processes is the reduction of interfacial energy", "B": "Nucleation in both cases requires overcoming the same activation energy barrier", "C": "Growth during recrystallization follows the same crystallographic relationship as solidification growth", "D": "The nucleation sites are identical in both processes, occurring preferentially at grain boundaries" }, "correct_answer": "A", "explanation": "The correct answer highlights the fundamental thermodynamic difference between the two processes. Solidification is driven by chemical potential difference while recrystallization by stored deformation energy. Option B exploits the common misconception that all nucleation barriers are similar. Option C traps those who overlook that recrystallization may maintain orientation relationships while solidification does not. Option D exploits the superficial similarity in nucleation site preferences while ignoring the different underlying mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2134, "question": "Provide the calculation formulas for the diffusion coefficient of interstitial atoms in face-centered cubic and body-centered cubic crystals (expressed in terms of lattice constant). The interstitial diffusion calculation formula is D=α²PΓ, where α is the distance between adjacent parallel crystal planes, P is the jump probability in a given direction, and Γ is the atomic jump frequency.", "answer": "Face-centered cubic crystal (fcc): D_fcc=(a²Γ)/24; Body-centered cubic crystal (bcc): D_bcc=(a²Γ)/12", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求提供具体的计算公式，并给出了扩散系数的计算框架（D=α²PΓ），最终答案以数学公式形式呈现（D_fcc=(a²Γ)/24; D_bcc=(a²Γ)/12），这符合计算题的特征，即需要应用公式进行推导或计算。 | 知识层次: 题目要求直接套用给定的扩散系数公式（D=α²PΓ），并根据面心立方和体心立方晶体的特点进行简单计算。虽然需要理解晶体结构的基本知识，但主要考查的是基本公式的直接应用和简单计算能力，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然题目提供了扩散系数的基本公式D=α²PΓ，但正确选项直接给出了fcc和bcc晶体结构的扩散系数计算公式，只需要简单套用即可。不需要进行多个公式的组合或复杂推导，属于对基本公式的直接应用。", "convertible": true, "correct_option": "Face-centered cubic crystal (fcc): D_fcc=(a²Γ)/24; Body-centered cubic crystal (bcc): D_bcc=(a²Γ)/12", "choice_question": "What are the calculation formulas for the diffusion coefficient of interstitial atoms in face-centered cubic and body-centered cubic crystals (expressed in terms of lattice constant)? The interstitial diffusion calculation formula is D=α²PΓ, where α is the distance between adjacent parallel crystal planes, P is the jump probability in a given direction, and Γ is the atomic jump frequency.", "conversion_reason": "The original question is a calculation question with a specific and clear answer. It can be converted into a multiple-choice question by presenting the correct formula as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Face-centered cubic crystal (fcc): D_fcc=(a²Γ)/24; Body-centered cubic crystal (bcc): D_bcc=(a²Γ)/12", "B": "Face-centered cubic crystal (fcc): D_fcc=(a²Γ)/12; Body-centered cubic crystal (bcc): D_bcc=(a²Γ)/24", "C": "Face-centered cubic crystal (fcc): D_fcc=(a²Γ)/6; Body-centered cubic crystal (bcc): D_bcc=(a²Γ)/8", "D": "Face-centered cubic crystal (fcc): D_fcc=(a²Γ)/8; Body-centered cubic crystal (bcc): D_bcc=(a²Γ)/6" }, "correct_answer": "A", "explanation": "The correct answer is A because in fcc crystals, interstitial atoms have 12 possible jump directions but only 1/2 probability per direction (P=1/12), while in bcc there are 8 possible directions with P=1/8. Option B reverses the coefficients, exploiting the common confusion between coordination numbers. Option C uses plausible-looking but incorrect fractions that might seem reasonable for surface diffusion. Option D mimics common coefficients for vacancy diffusion, targeting those who confuse interstitial and vacancy mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4417, "question": "Give the approximate temperature at which it is desirable to heat a 0.25 wt% C iron-carbon alloy during a full anneal heat treatment.", "answer": "About 880°C (1510°F)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从选项中选择或进行判断。虽然答案是一个具体的数值，但题目并未提供选项或要求进行计算，而是需要基于知识直接回答，类似于简答题的形式。 | 知识层次: 题目考查对铁碳合金热处理温度的直接应用，属于基本知识的简单应用，不需要复杂的计算或分析 | 难度: 在选择题型内，该题目属于简单应用层次，仅需要考生直接套用基本知识（铁碳相图中的A3线温度）即可得出答案，无需复杂计算或多步骤推理。题目考察的是对基础知识的直接回忆和应用能力，符合等级2\"简单应用过程描述\"的标准。", "convertible": true, "correct_option": "About 880°C (1510°F)", "choice_question": "What is the approximate temperature at which it is desirable to heat a 0.25 wt% C iron-carbon alloy during a full anneal heat treatment?", "conversion_reason": "The answer is a specific and standard value, making it suitable for conversion into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "880°C (1510°F)", "B": "723°C (1333°F)", "C": "950°C (1742°F)", "D": "650°C (1202°F)" }, "correct_answer": "A", "explanation": "The correct answer is A (880°C) because full annealing requires heating to about 50°C above the A3 line in the Fe-C phase diagram for hypoeutectoid steels. Option B (723°C) is the eutectoid temperature, which is a common but incorrect intuitive choice for annealing temperature. Option C (950°C) is too high and risks grain coarsening, exploiting the AI's tendency to overestimate temperatures for safety. Option D (650°C) is below the A1 line, exploiting confusion with stress relief annealing temperatures.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3190, "question": "In the symmetric tilt grain boundary of face-centered cubic metal $\\\\mathrm{Cu}$, the spacing between two positive edge dislocations is $D=1000\\\\mathrm{nm}$. Assuming the extra half-plane of the edge dislocation is the (110) plane and $d_{110}=0.1278\\\\mathrm{~nm}$, find the tilt angle $\\\\theta$ of the tilt grain boundary.", "answer": "The unit dislocation of the face-centered cubic structure is $b=\\\\frac{a}{2}\\\\langle110\\\\rangle$. Since the {110} plane has an extra atomic plane, $b=2d_{110}=2\\\\times0.1278=0.2556\\\\mathrm{nm}$. The tilt angle $\\\\theta$ of the tilt grain boundary can be calculated using the following deformation formula: $$ \\\\theta\\\\approx\\\\frac{b}{D}=\\\\frac{0.2556}{1000}=2.556\\\\times10^{-4}\\\\times\\\\frac{180}{\\\\pi}\\\\approx0.0146^{\\\\circ} $$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解倾斜角θ，答案中给出了具体的计算步骤和最终数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，即通过已知的位错间距和晶面间距计算倾斜角度，不需要多步计算或复杂的概念关联。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式进行计算，即通过已知的位错间距和位错矢量计算倾斜角度。解题步骤简单，无需复杂的推理或多步骤计算，属于最基础的难度等级。", "convertible": true, "correct_option": "0.0146°", "choice_question": "In the symmetric tilt grain boundary of face-centered cubic metal $\\mathrm{Cu}$, the spacing between two positive edge dislocations is $D=1000\\mathrm{nm}$. Assuming the extra half-plane of the edge dislocation is the (110) plane and $d_{110}=0.1278\\mathrm{~nm}$, what is the tilt angle $\\theta$ of the tilt grain boundary?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0146°", "B": "0.0073°", "C": "0.0292°", "D": "0.0219°" }, "correct_answer": "A", "explanation": "The correct answer is A (0.0146°) calculated using θ ≈ b/D where b = d110 = 0.1278 nm. Option B (0.0073°) is a common error from using b = d110/2, exploiting the misconception about Burgers vector magnitude. Option C (0.0292°) doubles the correct angle, targeting those who confuse tilt angle with misorientation angle. Option D (0.0219°) is a weighted average of plausible but incorrect values, designed to catch AI models making interpolation errors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4090, "question": "For an aligned fibrous composite, when a stress is applied in a direction that is parallel to the fibers, what is the reinforcement efficiency?(a) 0(b) \\frac{1}{5}(c) \\frac{3}{8}(d) \\frac{3}{4}(e) 1", "answer": "For an aligned fibrous composite when the stress is applied parallel to the fibers, the reinforcement efficiency is 1 .", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项(a)到(e)中选择正确答案，符合选择题的特征 | 知识层次: 题目考查的是对齐纤维复合材料在应力平行于纤维方向时的增强效率这一基本概念的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆复合材料中纤维排列方向与应力方向平行时的增强效率定义即可作答，无需复杂理解或分析步骤。", "convertible": true, "correct_option": "e", "choice_question": "For an aligned fibrous composite, when a stress is applied in a direction that is parallel to the fibers, what is the reinforcement efficiency?", "conversion_reason": "The original question is already in a multiple-choice format with a clear correct option (e) corresponding to the answer provided.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The fiber-matrix interface strength exceeds the matrix yield strength", "B": "The critical fiber length is exactly 10 times the fiber diameter", "C": "The fiber aspect ratio is greater than the stress transfer length ratio", "D": "The composite strain matches the matrix plastic deformation onset" }, "correct_answer": "A", "explanation": "Correct answer A addresses the fundamental requirement for effective load transfer in composites. The key deception in other options: B uses a specific but arbitrary length ratio that seems plausible but is irrelevant. C sounds technically correct but reverses the actual relationship needed. D creates confusion by mixing elastic and plastic deformation concepts. Advanced AIs may over-analyze these nuances and select the wrong option.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1830, "question": "Glass has the following general properties: (13)", "answer": "Metastability", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对玻璃的一般性质进行描述，答案\"Metastability\"是一个需要解释和论述的概念，而不是简单的选择或判断。 | 知识层次: 题目考查对玻璃基本性质（亚稳态）的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅考察对玻璃基本性质\"Metastability\"这一基础概念的简单记忆和识别，属于最基础的定义简答类型。题目无需解释或分析，只需选择正确术语，符合等级1的基本定义简答标准。", "convertible": true, "correct_option": "Metastability", "choice_question": "Which of the following is a general property of glass?", "conversion_reason": "The answer is a standard term (Metastability), which can be used as the correct option in a multiple-choice question. The original question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metastability", "B": "Crystalline long-range order", "C": "Definite melting point", "D": "Anisotropic thermal conductivity" }, "correct_answer": "A", "explanation": "The correct answer is A because glass is a metastable material that retains its amorphous structure indefinitely at room temperature. Option B exploits the common misconception that all solids must have crystalline order. Option C traps those who confuse glass transition temperature with a true melting point. Option D uses the intuitive but incorrect assumption that amorphous materials must exhibit directional properties like crystals.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4127, "question": "Are carbon-carbon composites low cost?", "answer": "The answer does not specify low cost.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个是非判断问题，询问碳碳复合材料是否低成本，答案给出了明确的判断（没有明确说明低成本），符合判断题的特征。 | 知识层次: 题目考查对碳碳复合材料成本这一基本概念的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 该题目属于基础概念记忆层次，仅需判断\"碳碳复合材料是否低成本\"这一简单陈述的正确性。正确选项直接给出了明确答案，不需要任何推理或概念间的比较分析，是最基础的正误判断题。", "convertible": true, "correct_option": "The answer does not specify low cost.", "choice_question": "Are carbon-carbon composites low cost?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All carbon-carbon composites exhibit superior thermal conductivity in all directions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because carbon-carbon composites exhibit anisotropic properties. While they may have high thermal conductivity in the fiber direction, their transverse thermal conductivity is typically much lower. The use of 'all' and 'in all directions' creates an absolute claim that doesn't account for material anisotropy, which is a fundamental characteristic of fiber-reinforced composites.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2581, "question": "What is the fundamental reason for the formation of deformation texture (or processing texture)?", "answer": "The fundamental reason for the formation of deformation texture is that during processing, each grain slips along certain slip planes and rotates according to specific rules, causing the slip direction to align with the principal strain direction or the slip plane to align with the compression plane. Therefore, when the deformation is sufficiently large, the slip directions or slip planes of a large number of grains will become parallel to the tensile direction or compression plane, thus forming the texture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释变形织构形成的基本原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释变形织构形成的根本原因，涉及晶体滑移、旋转规则以及应变方向的关联，需要综合运用材料科学中的晶体塑性变形机理进行推理分析，思维过程较为深入。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求深入理解变形织构形成的根本原因，涉及复杂的晶体滑移机制和旋转规则的综合分析。正确选项不仅需要掌握多个专业概念（如滑移面、主应变方向、压缩平面等），还需要将这些概念串联起来进行机理层面的深度解释。此外，题目要求考生能够推理出大变形条件下大量晶粒的取向排列规律，这属于复杂现象的全面分析能力，远超选择题型中常规的知识点识别或简单应用层次。", "convertible": true, "correct_option": "The fundamental reason for the formation of deformation texture is that during processing, each grain slips along certain slip planes and rotates according to specific rules, causing the slip direction to align with the principal strain direction or the slip plane to align with the compression plane. Therefore, when the deformation is sufficiently large, the slip directions or slip planes of a large number of grains will become parallel to the tensile direction or compression plane, thus forming the texture.", "choice_question": "What is the fundamental reason for the formation of deformation texture (or processing texture)?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The alignment of slip directions with principal strain direction due to crystallographic rotation during plastic deformation", "B": "The preferential dissolution of certain crystallographic planes during processing", "C": "The minimization of surface energy through atomic rearrangement at grain boundaries", "D": "The thermal activation of specific slip systems during recrystallization" }, "correct_answer": "A", "explanation": "The correct answer A describes the fundamental mechanism of texture formation through crystallographic rotation during plastic deformation. Option B is a cognitive bias trap, confusing texture formation with corrosion phenomena. Option C exploits surface energy minimization intuition which is irrelevant to deformation texture. Option D is a multi-level trap combining correct recrystallization concepts with incorrect timing (texture forms during deformation, not recrystallization).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3571, "question": "From what kind of material would the temperature indicator be made?", "answer": "The temperature indicator is made from bimetallic materials, which consist of two materials with different coefficients of thermal expansion bonded together.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释温度指示器的材料类型，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对温度指示器材料的基本概念记忆，仅需回答双金属材料的定义和基本原理，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对温度指示器材料的基本定义记忆，属于最基础的概念性知识。正确选项直接给出了明确的定义和组成材料，不需要任何解释或分析过程，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "bimetallic materials, which consist of two materials with different coefficients of thermal expansion bonded together", "choice_question": "From what kind of material would the temperature indicator be made?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Shape memory alloys that exhibit reversible phase transformation", "B": "Bimetallic materials with differing thermal expansion coefficients", "C": "Piezoelectric ceramics generating voltage under temperature gradients", "D": "Thermochromic polymers changing optical properties with temperature" }, "correct_answer": "B", "explanation": "The correct answer is B because bimetallic strips are specifically designed to bend predictably with temperature changes due to their differential expansion properties. Option A exploits the AI's likely familiarity with temperature-sensitive materials but incorrectly applies shape memory effect. Option C uses piezoelectricity which is unrelated to temperature indication. Option D introduces a plausible but incorrect mechanism of optical rather than mechanical response.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 683, "question": "All symmetry elements present in macroscopic crystals must pass through the center of the crystal", "answer": "√", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（√表示正确），符合判断题的特征 | 知识层次: 题目考查对晶体对称元素基本概念的记忆和理解，属于基础概念记忆性知识。 | 难度: 该题目属于基础概念正误判断，仅需记忆晶体对称元素的基本定义即可作答，无需深入理解或分析。在选择题型中属于最简单的难度等级。", "convertible": true, "correct_option": "√", "choice_question": "All symmetry elements present in macroscopic crystals must pass through the center of the crystal", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All symmetry elements present in macroscopic crystals must pass through the center of the crystal", "options": [ "True", "False" ], "correct_answer": "True", "explanation": "This statement is true because in macroscopic crystals, symmetry operations must leave the crystal looking the same, which requires all symmetry elements (like rotation axes, mirror planes, and inversion centers) to pass through the center of the crystal. A common misconception is that symmetry elements can be located anywhere within the crystal, but this would violate the requirement of leaving the entire crystal invariant under the symmetry operation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 814, "question": "For a face-centered cubic crystal with a movable slip system of (111)[110], please indicate the Burgers vector of the unit dislocation causing the slip.", "answer": "Burgers vector; b=a/2 [110]", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释并给出Burgers vector的具体表达式，需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求识别面心立方晶体中特定滑移系(111)[110]的单位位错的Burgers矢量，这需要理解晶体结构、滑移系和位错的基本概念，并将这些概念关联起来进行分析。虽然不涉及多步计算，但需要对晶体学方向和Burgers矢量的关系有中等程度的理解，属于概念关联和综合分析层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握面心立方晶体的滑移系统以及伯格斯矢量的概念，并能正确识别单位位错的伯格斯矢量。虽然题目给出了滑移系统（111）[110]，但需要考生知道在面心立方晶体中，单位位错的伯格斯矢量通常是a/2<110>类型。这需要一定的晶体学知识和综合分析能力，但不需要多步计算或深度关联性分析。", "convertible": true, "correct_option": "b=a/2 [110]", "choice_question": "For a face-centered cubic crystal with a movable slip system of (111)[110], what is the Burgers vector of the unit dislocation causing the slip?", "conversion_reason": "The answer is a standard term and can be presented as a choice among other possible Burgers vectors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "a/2 [110]", "B": "a [110]", "C": "a/2 [111]", "D": "a/6 [112]" }, "correct_answer": "A", "explanation": "The correct Burgers vector for a unit dislocation in FCC crystals is a/2 [110], as it represents the shortest perfect lattice translation vector in the slip direction. Option B is incorrect because it represents a full lattice translation which would require breaking too many atomic bonds. Option C uses the correct magnitude but wrong direction (normal to slip plane). Option D represents a partial dislocation vector which, while existing in FCC crystals, is not the unit dislocation responsible for primary slip.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 658, "question": "What are the adverse effects of texture on metal materials?", "answer": "Texture induces anisotropy in metals, and anisotropy often causes difficulties in the processing and use of metals. Deep-drawn metal cups may develop ears. Polycrystalline metal rods with texture can significantly elongate after repeated heating and cooling cycles.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释纹理对金属材料的不良影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释纹理对金属材料的不良影响，涉及纹理引起的各向异性及其在加工和使用中的具体问题（如深冲杯的耳状突起、多晶金属棒的热循环伸长）。这需要理解纹理的基本概念，并将其与金属材料的实际应用问题联系起来，属于中等应用层次的知识。 | 难度: 在选择题中属于中等难度，需要理解金属材料的织构效应及其对性能的影响，涉及多个概念（各向异性、加工难度、深冲杯耳现象、热循环变形）的综合分析，但选项已提供明确的关联性解释，无需额外推导。", "convertible": true, "correct_option": "Texture induces anisotropy in metals, and anisotropy often causes difficulties in the processing and use of metals. Deep-drawn metal cups may develop ears. Polycrystalline metal rods with texture can significantly elongate after repeated heating and cooling cycles.", "choice_question": "What are the adverse effects of texture on metal materials?", "conversion_reason": "The answer provided is a detailed and specific explanation of the adverse effects of texture on metal materials, which can be directly used as the correct option in a multiple-choice question format. The original question can remain unchanged as it is already a clear and direct question suitable for a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Texture reduces dislocation mobility by creating preferential slip planes", "B": "Texture increases thermal conductivity anisotropy by aligning phonon transport paths", "C": "Texture causes hydrogen embrittlement by creating high-energy grain boundaries", "D": "Texture decreases corrosion resistance by exposing more active crystallographic planes" }, "correct_answer": "A", "explanation": "Correct answer A addresses the fundamental issue of texture-induced anisotropy affecting dislocation movement. Option B is a thermal properties trap that confuses electron conduction with dislocation effects. Option C exploits hydrogen embrittlement misconceptions by incorrectly associating it with texture rather than microstructure. Option D creates a corrosion resistance illusion by mixing up crystallographic plane activity with texture effects.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 415, "question": "1. In the ionic crystal structure, the distance between positive and negative ions depends on (2)", "answer": "The sum of positive and negative ion radii", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求用文字解释离子晶体结构中正负离子间距的决定因素，答案是一个简短的文字描述，不需要计算或选择选项 | 知识层次: 题目考查的是离子晶体结构中正负离子间距与离子半径关系的基本概念记忆，属于基础概念记忆性知识。 | 难度: 在选择题型中属于基础难度，仅需记忆离子晶体结构中正负离子间距的基本定义（正负离子半径之和），不需要进行概念解释或复杂分析。", "convertible": true, "correct_option": "The sum of positive and negative ion radii", "choice_question": "In the ionic crystal structure, the distance between positive and negative ions depends on:", "conversion_reason": "The answer is a standard term or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The sum of positive and negative ion radii", "B": "The difference between positive and negative ion radii", "C": "The ratio of positive to negative ion radii", "D": "The product of positive and negative ion radii multiplied by the Madelung constant" }, "correct_answer": "A", "explanation": "The correct answer is A because in ionic crystals, the distance between ions is determined by the sum of their radii when they are in contact. Option B exploits the cognitive bias of assuming subtraction is involved in distance calculations. Option C creates confusion by introducing a ratio, which is relevant for coordination number but not interionic distance. Option D is a multi-layer trap combining a correct concept (Madelung constant) with incorrect mathematical operation, appealing to those who overcomplicate the problem.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2186, "question": "Briefly analyze the essential similarities and differences of solid solution strengthening", "answer": "Solid solution strengthening results from the interaction between dislocations and solute atoms, namely the Cottrell atmosphere hindering dislocation motion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求简要分析固溶强化的本质异同点，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求分析固溶强化的本质相似性和差异性，涉及位错与溶质原子的相互作用机制（Cottrell气团阻碍位错运动），需要综合运用材料科学中的位错理论和强化机制知识进行机理层面的解释和分析。这超出了简单记忆或基础应用的范畴，属于需要深入理解和推理分析的复杂问题。 | 难度: 在选择题型中，该题目要求考生不仅理解固溶强化的基本概念，还需要掌握位错与溶质原子相互作用的机理（如Cottrell气团对位错运动的阻碍作用）。这属于对材料强化机理的深度解释，需要考生具备将微观机制与宏观性能联系起来的分析能力，符合等级4\"机理深度解释\"的标准。选择题型中仅提供正确选项时，判断该选项的准确性需要较高的专业知识储备。", "convertible": true, "correct_option": "Solid solution strengthening results from the interaction between dislocations and solute atoms, namely the Cottrell atmosphere hindering dislocation motion.", "choice_question": "Which of the following best describes the mechanism of solid solution strengthening?", "conversion_reason": "The answer is a standard explanation of the concept, which can be adapted into a multiple-choice format by presenting it as the correct option among plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Solid solution strengthening results from the interaction between dislocations and solute atoms, namely the Cottrell atmosphere hindering dislocation motion", "B": "Solid solution strengthening occurs when solute atoms increase the overall elastic modulus of the crystal lattice", "C": "Solid solution strengthening is primarily caused by solute atoms reducing the stacking fault energy of the matrix", "D": "Solid solution strengthening arises from solute atoms creating new grain boundaries that impede dislocation movement" }, "correct_answer": "A", "explanation": "The correct answer is A because solid solution strengthening fundamentally involves solute atoms interacting with dislocations through strain fields (Cottrell atmosphere), which hinders dislocation motion. Option B is incorrect because while elastic modulus affects dislocation motion, it's not the primary mechanism. Option C is a subtle trap as stacking fault energy affects partial dislocations but isn't the main strengthening mechanism. Option D exploits the common confusion between grain boundary strengthening and solid solution strengthening mechanisms.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 253, "question": "Explain the difference in diffusion coefficients between hydrogen and nickel in face-centered cubic iron.", "answer": "Compared to nickel atoms, hydrogen atoms are much smaller and can diffuse more easily through the gaps in face-centered cubic iron.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释氢和镍在面心立方铁中扩散系数的差异，需要文字解释和论述，而不是选择、判断或计算。答案提供了详细的解释，符合简答题的特征。 | 知识层次: 题目要求解释氢和镍在面心立方铁中扩散系数的差异，涉及原子尺寸效应和晶体结构间隙扩散机理的综合分析，需要理解扩散机制和原子尺寸对扩散行为的影响，属于复杂分析和推理解释的范畴。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅理解扩散系数的概念，还需要掌握氢和镍原子在面心立方铁中的扩散机理差异。正确选项涉及对原子尺寸效应的深入理解以及晶体结构间隙扩散的机理分析，这需要考生具备综合运用材料科学知识的能力。虽然题目以选择题形式呈现，但考察的知识深度和推理复杂度明显高于基础概念题，属于需要机理深度解释的难度等级。", "convertible": true, "correct_option": "Compared to nickel atoms, hydrogen atoms are much smaller and can diffuse more easily through the gaps in face-centered cubic iron.", "choice_question": "What is the difference in diffusion coefficients between hydrogen and nickel in face-centered cubic iron?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hydrogen diffuses faster due to its smaller atomic radius enabling interstitial diffusion, while nickel moves via slower vacancy-mediated diffusion", "B": "Nickel diffuses faster because its similar atomic size to iron reduces lattice strain energy during substitutional diffusion", "C": "Both elements diffuse at similar rates since their diffusion coefficients are primarily determined by the iron host lattice properties", "D": "Hydrogen diffuses slower because its high electronegativity creates strong bonds with iron atoms" }, "correct_answer": "A", "explanation": "The correct answer is A because hydrogen's small size allows interstitial diffusion through FCC iron's octahedral/tetrahedral sites, while nickel's similar size to iron requires vacancy-mediated substitutional diffusion. Option B is incorrect because while nickel's size similarity reduces strain, substitutional diffusion is still much slower than interstitial. Option C is wrong as diffusion mechanisms differ fundamentally between interstitial and substitutional cases. Option D is a trap exploiting the false intuition that hydrogen's electronegativity would dominate over its size advantage in diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1842, "question": "What is the relationship between △L/L and sintering time in the dissolution-precipitation mass transfer process?", "answer": "(30) △L/L∝t^(1/3)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释烧结时间与△L/L之间的关系，答案是一个数学表达式，需要简要说明其物理意义，属于需要文字解释的简答题类型。 | 知识层次: 题目涉及溶解-沉淀传质过程中烧结时间与长度变化的关系，需要理解并应用相关公式（△L/L∝t^(1/3)），属于多步计算和概念关联的中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解溶解-沉淀传质过程的基本原理，并能将烧结时间与尺寸变化关系进行综合分析。题目要求考生掌握△L/L与时间t的1/3次方关系这一特定知识点，并能在选项中进行正确识别。虽然不涉及多步计算，但需要对烧结动力学有较好的概念理解。", "convertible": true, "correct_option": "△L/L∝t^(1/3)", "choice_question": "What is the relationship between △L/L and sintering time in the dissolution-precipitation mass transfer process?", "conversion_reason": "The answer is a standard mathematical relationship, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "△L/L∝t^(1/3)", "B": "△L/L∝t^(1/2)", "C": "△L/L∝ln(t)", "D": "△L/L∝exp(-kt)" }, "correct_answer": "A", "explanation": "The correct answer is A because the dissolution-precipitation process follows a cubic time dependence due to the diffusion-controlled mass transfer mechanism. Option B is a common misconception from classical diffusion theory (parabolic law). Option C exploits confusion with creep deformation kinetics, while Option D mimics first-order reaction kinetics which doesn't apply here. Advanced AI might incorrectly select B due to overgeneralization of diffusion behavior.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3048, "question": "What type of chemical bond is primarily found in oxides? A. Metallic bond B. Covalent bond C. Molecular bond D. Ionic bond", "answer": "D", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从四个选项中选择关于氧化物中主要化学键类型的正确答案 | 知识层次: 题目考查对氧化物中主要化学键类型的基础概念记忆，属于定义和分类层面的基本知识。 | 难度: 在选择题型中，此题属于基础概念记忆类型，仅需识别氧化物中主要存在的化学键类型（离子键），无需进行概念辨析或复杂分析。题目选项直接对应基本知识点，属于最简单的难度等级。", "convertible": true, "correct_option": "D. Ionic bond", "choice_question": "What type of chemical bond is primarily found in oxides?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Covalent bond with partial ionic character", "B": "Pure covalent bond with sp3 hybridization", "C": "Metallic bond with electron delocalization", "D": "Ionic bond" }, "correct_answer": "D", "explanation": "The correct answer is D because most oxides form ionic bonds due to the large electronegativity difference between oxygen and metals. Option A is designed to exploit the AI's tendency to overcomplicate simple concepts by introducing hybrid bonding. Option B targets the misconception that all oxygen compounds must involve covalent bonding. Option C exploits the AI's potential confusion between metallic oxides and pure metals. All incorrect options leverage the AI's difficulty in properly weighting electronegativity differences when predicting bond types.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2102, "question": "Point out the errors in the following concept and correct them: Repeatedly 'melting and solidifying' a solid solution alloy rod and using directional rapid solidification can effectively purify the metal.", "answer": "Repeatedly perform zone melting and use directional slow solidification.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。答案也是以文字形式给出修正后的正确概念。 | 知识层次: 题目要求识别并纠正错误概念，涉及对金属纯化方法的理解和应用，需要综合分析熔化、凝固过程对金属纯度的影响，并正确选择工艺参数（如快速或慢速凝固）。这超出了简单记忆的范畴，需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求识别并纠正错误概念，涉及对\"melting and solidifying\"与\"zone melting\"、\"rapid solidification\"与\"slow solidification\"等专业术语的区分和理解。虽然不需要复杂的计算，但需要对材料科学中的提纯原理有较深入的理解，并能将不同概念关联起来进行综合分析。", "convertible": true, "correct_option": "Repeatedly perform zone melting and use directional slow solidification.", "choice_question": "Which of the following correctly describes the process to effectively purify a solid solution alloy rod?", "conversion_reason": "The original short answer question asks for the correction of a specific concept, which can be rephrased into a multiple-choice format by presenting the correct method among possible options. The correct answer is a standard and concise statement that can serve as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Repeatedly perform zone melting and use directional slow solidification", "B": "Apply rapid quenching followed by annealing at eutectic temperature", "C": "Use centrifugal casting with multiple remelting cycles", "D": "Alternate between solution treatment and precipitation hardening" }, "correct_answer": "A", "explanation": "The correct answer is A because zone melting with directional slow solidification is the established method for purifying solid solution alloys, allowing controlled segregation of impurities. Option B is incorrect because rapid quenching introduces defects and eutectic temperature is irrelevant for solid solutions. Option C is a cognitive bias trap, as centrifugal casting is for shape casting not purification. Option D exploits professional intuition by using legitimate heat treatment terms in the wrong context for purification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3486, "question": "Can one prolonged tempering at 560°C replace three tempering processes at 560°C?", "answer": "No. Because a single tempering is difficult to completely eliminate retained austenite, multiple tempering processes are required to reduce the retained austenite to the minimum amount. Moreover, each subsequent tempering can eliminate the internal stress generated by the transformation of austenite into martensite during the previous tempering.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目是一个是非判断问题，要求判断“一次长时间回火是否可以替代三次回火”这一陈述的正确性。答案明确给出了“No”并解释了原因，符合判断题的特征。 | 知识层次: 题目涉及回火工艺对残余奥氏体消除的影响，需要理解多次回火的作用机理和残余奥氏体转变的复杂过程。解答不仅需要知道多次回火的必要性，还需要分析每次回火对内部应力和组织转变的影响，属于综合运用和推理分析的层次。 | 难度: 在选择题型中属于高难度，需要深入理解回火工艺的机理，包括残余奥氏体的消除、内应力的产生与消除等复杂过程。题目要求综合运用材料科学知识进行推理分析，判断单一长时间回火是否能替代多次回火的效果，涉及多个知识点的综合应用和机理解释。", "convertible": true, "correct_option": "No. Because a single tempering is difficult to completely eliminate retained austenite, multiple tempering processes are required to reduce the retained austenite to the minimum amount. Moreover, each subsequent tempering can eliminate the internal stress generated by the transformation of austenite into martensite during the previous tempering.", "choice_question": "Can one prolonged tempering at 560°C replace three tempering processes at 560°C?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "For all steel alloys, a single prolonged tempering at 560°C can completely replace three separate tempering processes at the same temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While prolonged tempering may be effective for some specific steel compositions, the general principle requires multiple tempering cycles to fully transform retained austenite and relieve internal stresses. The statement's use of 'all steel alloys' makes it incorrect, as different alloys respond differently to tempering processes. A key misunderstanding would be assuming all steels behave identically during heat treatment.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3657, "question": "Suppose we introduce one carbon atom for every 100 iron atoms in an interstitial position in BCC iron, giving a lattice parameter of 0.2867 nm. For the Fe-C alloy, find the packing factor.", "answer": "0.681", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解Fe-C合金的堆积因子，答案是一个具体的数值结果(0.681)，这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括计算晶胞体积、原子体积和间隙原子体积，并应用堆积因子的公式。虽然不涉及复杂的推理分析或机理解释，但需要综合运用材料科学中的基本概念和计算方法。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构、间隙原子位置、晶格参数与原子半径的关系等多个概念，并进行多步计算（包括原子半径计算、体积计算和堆积因子公式应用）。虽然题目提供了关键参数（晶格常数），但仍需要综合运用材料晶体学知识才能得出正确选项。", "convertible": true, "correct_option": "0.681", "choice_question": "Suppose we introduce one carbon atom for every 100 iron atoms in an interstitial position in BCC iron, giving a lattice parameter of 0.2867 nm. For the Fe-C alloy, the packing factor is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.681", "B": "0.724", "C": "0.648", "D": "0.703" }, "correct_answer": "A", "explanation": "The correct answer is 0.681, calculated by considering the volume occupied by both iron and carbon atoms in the BCC structure with the given lattice parameter. Option B (0.724) is a trap for those who incorrectly assume FCC packing efficiency. Option C (0.648) results from miscalculating carbon's contribution. Option D (0.703) exploits confusion between atomic packing factor and theoretical density calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2385, "question": "Can all parts of a dislocation loop be edge dislocations? Why?", "answer": "The Burgers vector of an edge dislocation is perpendicular to the dislocation line. If the Burgers vector is perpendicular to the plane of the dislocation loop, then every part of the dislocation loop is an edge dislocation. The slip plane of such a dislocation is the prismatic plane formed by the dislocation loop and the direction of the Burgers vector. This type of dislocation is also called a prismatic dislocation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么位错环的所有部分都可以是刃位错，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求对位错环的性质进行深入分析，涉及位错类型与伯格斯矢量的关系，以及位错滑移面的确定。需要综合运用位错理论的知识，进行推理和机理解释，属于较高层次的认知能力要求。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求考生不仅理解位错环和刃位错的基本概念，还需要综合运用Burgers矢量的方向性、位错线与滑移面的几何关系等知识进行推理分析。正确选项涉及复杂的机理解释（棱柱位错的形成）和空间几何关系的全面分析，这远超出选择题通常考查的记忆或简单应用层面，需要考生具备将多个高阶概念整合分析的能力。", "convertible": true, "correct_option": "The Burgers vector of an edge dislocation is perpendicular to the dislocation line. If the Burgers vector is perpendicular to the plane of the dislocation loop, then every part of the dislocation loop is an edge dislocation. The slip plane of such a dislocation is the prismatic plane formed by the dislocation loop and the direction of the Burgers vector. This type of dislocation is also called a prismatic dislocation.", "choice_question": "Can all parts of a dislocation loop be edge dislocations? Why?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be kept as is, and the answer can be used as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, if the Burgers vector is perpendicular to the plane of the loop, creating a prismatic dislocation", "B": "No, because dislocation loops must contain both edge and screw components by definition", "C": "Yes, but only for perfect dislocation loops in FCC crystals", "D": "No, because the curvature of the loop inherently requires mixed character dislocations" }, "correct_answer": "A", "explanation": "The correct answer is A because a prismatic dislocation loop can indeed have pure edge character when the Burgers vector is perpendicular to the loop plane. Option B is incorrect and exploits the common misconception that loops must contain mixed dislocations. Option C is a trap using FCC crystal specificity which is irrelevant to the fundamental crystallography question. Option D is designed to trigger intuitive reasoning about curvature effects, but ignores the special case of prismatic loops.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 561, "question": "What are the factors affecting atomic diffusion in crystalline solids? Briefly explain the influence of crystal structure and solid solution type.", "answer": "Crystal structure and solid solution type. In crystal structures with smaller packing density, the diffusion activation energy is lower, making diffusion easier to occur; in crystal structures with lower symmetry, the anisotropy of the diffusion coefficient is significant; the diffusion activation energy in interstitial solid solutions is much smaller than that in substitutional solid solutions, facilitating easier diffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释影响原子扩散的因素，并简要说明晶体结构和固溶体类型的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释影响原子扩散的因素，并具体分析晶体结构和固溶体类型的影响。这需要理解扩散的基本原理，并将这些原理与具体的材料特性（如晶体结构对称性、固溶体类型）联系起来进行分析。虽然不涉及复杂的计算或创新设计，但需要多步的概念关联和综合分析，超出了简单记忆或直接套用的层次。 | 难度: 在选择题型中，该题目要求考生不仅理解原子扩散的基本概念，还需要综合分析晶体结构和固溶体类型对扩散的影响。题目涉及多个知识点的关联，包括晶体结构的对称性、堆积密度以及不同类型固溶体的扩散激活能差异。此外，解题过程需要考生进行多角度分析，比较不同条件下的扩散行为，这超出了简单的记忆或单一概念的应用，属于较高层次的综合分析能力要求。因此，在选择题型内属于较高难度等级。", "convertible": true, "correct_option": "Crystal structure and solid solution type", "choice_question": "Which of the following are the main factors affecting atomic diffusion in crystalline solids?", "conversion_reason": "The answer to the short answer question is a standard term or concept, which can be converted into a multiple-choice format by listing possible factors and identifying the correct ones.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Crystal structure and solid solution type", "B": "Temperature and vacancy concentration", "C": "Grain size and dislocation density", "D": "All of the above" }, "correct_answer": "A", "explanation": "The correct answer is A because atomic diffusion in crystalline solids is primarily governed by the crystal structure (which determines diffusion pathways) and solid solution type (which affects solute-solvent interactions). Option B is a strong distractor as temperature and vacancies do influence diffusion rates, but they are secondary factors rather than primary structural determinants. Option C exploits the common misconception that microstructural features like grain boundaries and dislocations are the main drivers, while they actually provide alternative diffusion paths. Option D is a cognitive trap designed to catch models that fail to distinguish between primary and secondary influencing factors.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3130, "question": "Explain the basic concept and terminology: Twinning", "answer": "Twinning: One of the important forms of cold plastic deformation, occurring as a uniform shear within the crystal, always along certain crystallographic planes and directions. After deformation, the deformed part and the undeformed part exhibit a mirror-symmetric orientation relationship, hence this type of plastic deformation is called twinning.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释基本概念和术语，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查基本概念的记忆和理解，即孪生的定义、发生机制和特征，属于基础概念记忆层次。 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。虽然题目要求解释\"Twinning\"这一概念，但正确选项已经提供了明确的定义、发生机制和特征描述，不需要考生进行复杂的分析或比较多个概念。考生只需理解并记忆这些基本概念即可正确回答，因此属于中等难度。", "convertible": true, "correct_option": "Twinning: One of the important forms of cold plastic deformation, occurring as a uniform shear within the crystal, always along certain crystallographic planes and directions. After deformation, the deformed part and the undeformed part exhibit a mirror-symmetric orientation relationship, hence this type of plastic deformation is called twinning.", "choice_question": "Which of the following best describes the concept of twinning?", "conversion_reason": "The answer is a standard definition of a concept, which can be converted into a multiple-choice question format by presenting it as one of several options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Twinning: One of the important forms of cold plastic deformation, occurring as a uniform shear within the crystal, always along certain crystallographic planes and directions. After deformation, the deformed part and the undeformed part exhibit a mirror-symmetric orientation relationship, hence this type of plastic deformation is called twinning.", "B": "Twinning: A high-temperature diffusion-controlled process where atoms rearrange to form mirror-image crystal domains, commonly observed during recrystallization of metals.", "C": "Twinning: A defect formation mechanism where dislocations of opposite Burgers vectors combine to create a symmetrical lattice distortion, primarily occurring in FCC metals under tensile stress.", "D": "Twinning: An elastic deformation phenomenon where the crystal lattice temporarily distorts into mirror-symmetric configurations under applied stress, reverting upon stress removal." }, "correct_answer": "A", "explanation": "The correct answer A precisely describes twinning as a cold plastic deformation mechanism with mirror-symmetric orientation. Option B incorrectly associates twinning with high-temperature diffusion. Option C wrongly describes it as a dislocation combination mechanism. Option D inaccurately presents twinning as an elastic phenomenon. These distractors exploit common misconceptions about temperature dependence (B), dislocation mechanisms (C), and reversibility (D) in deformation processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4382, "question": "Explain why tempered martensite is much harder and stronger.", "answer": "Tempered martensite is harder and stronger inasmuch as there is much more ferrite-cementite phase boundary area for the smaller particles; thus, there is greater reinforcement of the ferrite phase, and more phase boundary barriers to dislocation motion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么回火马氏体更硬更强，需要文字解释和论述，答案提供了详细的解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释回火马氏体硬度与强度的机理，涉及相界面对位错运动的阻碍作用以及铁素体相的强化机制，需要综合运用材料科学中的相变、位错理论和强化机制等知识进行推理分析。 | 难度: 在选择题中属于最高难度等级，题目要求深入理解马氏体回火过程中的相变机理，并能分析相界面对位错运动的阻碍作用。正确选项涉及多尺度（相界面积、颗粒尺寸、强化机制）的综合分析，需要考生具备将微观结构特征与宏观力学性能关联的高级推理能力。这种复杂现象的全方位解释在选择题型中属于对知识深度和应用能力的最高要求。", "convertible": true, "correct_option": "Tempered martensite is harder and stronger inasmuch as there is much more ferrite-cementite phase boundary area for the smaller particles; thus, there is greater reinforcement of the ferrite phase, and more phase boundary barriers to dislocation motion.", "choice_question": "Why is tempered martensite much harder and stronger?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The high dislocation density in martensite is preserved during tempering, providing continuous strengthening", "B": "Tempering creates nanosized cementite precipitates that pin dislocations through Orowan strengthening", "C": "Carbon atoms remain in supersaturated solution after tempering, causing strong solid solution strengthening", "D": "The body-centered tetragonal structure transforms to a more densely packed face-centered cubic structure" }, "correct_answer": "B", "explanation": "Correct answer (B) is accurate because tempering does produce fine cementite particles that obstruct dislocation motion via Orowan mechanism. Option A exploits the common misconception that high dislocation density persists after tempering (actually reduced). Option C uses the intuitive but wrong idea that carbon remains supersaturated (it precipitates as cementite). Option D manipulates structural transformation knowledge (BCT→BCC, not FCC).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 327, "question": "How to improve the degree of grain refinement?", "answer": "The degree of grain refinement can be improved by adding heterogeneous nucleation agents or using high cooling rates during solidification, or through large deformation, recrystallization, or phase transformation methods.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释如何提高晶粒细化程度，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目要求解释如何提高晶粒细化程度，涉及多种方法（如添加异质形核剂、高冷却速率、大变形、再结晶和相变等），需要综合理解和应用多个材料科学概念。虽然不涉及复杂计算或深度机理分析，但需要将不同知识点关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及多种提高晶粒细化程度的方法，包括添加异质形核剂、高冷却速率、大变形、再结晶和相变等。虽然选项提供了明确的答案，但需要考生具备一定的材料科学知识，能够理解并关联这些不同的方法。因此，在选择题型中属于中等难度。", "convertible": true, "correct_option": "Adding heterogeneous nucleation agents or using high cooling rates during solidification, or through large deformation, recrystallization, or phase transformation methods.", "choice_question": "Which of the following methods can improve the degree of grain refinement?", "conversion_reason": "The answer is a standard set of methods that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Applying high-frequency ultrasonic vibration during solidification", "B": "Increasing the annealing temperature above the recrystallization point", "C": "Introducing dislocations through cold working followed by rapid quenching", "D": "Using a slower cooling rate to allow for more homogeneous nucleation" }, "correct_answer": "A", "explanation": "High-frequency ultrasonic vibration during solidification (A) is correct because it promotes grain refinement through cavitation-induced nucleation and fragmentation of growing dendrites. Option B is incorrect because while recrystallization can refine grains, temperatures above the recrystallization point would cause grain growth. Option C is a multi-step trap - cold working introduces dislocations but rapid quenching may not allow sufficient time for recrystallization. Option D exploits the common misconception that slower cooling improves microstructure, when in fact it leads to coarser grains due to reduced nucleation sites.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2339, "question": "Where should hydrogen atoms be located in the aluminum lattice? Why?", "answer": "The octahedral interstice is larger than the tetrahedral interstice, so hydrogen atoms reside in the octahedral interstice.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释氢原子在铝晶格中的位置及其原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解铝晶格中氢原子的位置选择，涉及八面体间隙和四面体间隙的比较，需要将晶体结构知识与原子尺寸效应进行关联分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解铝晶格中八面体间隙和四面体间隙的概念，并比较它们的尺寸大小。此外，还需要知道氢原子的尺寸与这些间隙的关系，综合分析得出氢原子应位于较大的八面体间隙。这涉及多步概念关联和综合分析，但不需要更深入的多角度分析或深度关联性分析。", "convertible": true, "correct_option": "The octahedral interstice is larger than the tetrahedral interstice, so hydrogen atoms reside in the octahedral interstice.", "choice_question": "Where should hydrogen atoms be located in the aluminum lattice?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Octahedral interstices due to their larger size compared to tetrahedral sites", "B": "Tetrahedral interstices because hydrogen's small radius fits better in smaller voids", "C": "Substitutional sites replacing aluminum atoms to form stable hydrides", "D": "Grain boundaries where hydrogen can be trapped by defects" }, "correct_answer": "A", "explanation": "The correct answer is A because octahedral interstices in the aluminum FCC lattice provide sufficient space for hydrogen atoms, despite their small size. Option B is a cognitive bias trap - while hydrogen is small, the tetrahedral sites are too small to accommodate it comfortably. Option C exploits substitutional site intuition from other metal-hydrogen systems, but hydrogen cannot replace aluminum atoms in the lattice. Option D uses a real phenomenon (hydrogen trapping at defects) but is incorrect for bulk lattice positioning.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2839, "question": "For a bcc crystal with a critical resolved shear stress of 60MPa on the (110)[111] slip system, how much stress must be applied in the [001] direction to initiate slip?", "answer": "Vector dot product:\\n[001] direction:\\na⋅b=|a|⋅|b|cosθ⇒cosθ=(a⋅b)/(|a|⋅|b|)=(a1b1+a2b2+a3b3)/(√(a1²+a2²+a3²)⋅√(b1²+b2²+b3²))\\ncosλ=1/(1×√3)=1/√3,\\ncosφ=0/(1×√2)=0\\nσ=τt/(cosλcosφ)=60/((1/√3)×0)=∞,\\nTherefore, slip cannot be initiated in this direction no matter how much stress is applied.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过数值计算和公式应用来解决问题，涉及向量点积和临界分切应力的计算，最终得出一个具体的数值结果（∞）。答案展示了详细的数学推导过程，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括向量点积、方向余弦计算和临界分切应力公式的应用。虽然不涉及复杂的综合分析或机理解释，但需要理解晶体滑移系统的基本原理，并能正确应用相关公式进行计算。 | 难度: 在选择题中属于高难度，需要深入理解晶体滑移系统的概念，进行多步骤的向量点积计算，并综合分析临界分切应力的应用。题目涉及复杂的多变量计算和概念关联，对学生的知识掌握深度和计算能力要求较高。", "convertible": true, "correct_option": "Slip cannot be initiated in this direction no matter how much stress is applied.", "choice_question": "For a bcc crystal with a critical resolved shear stress of 60MPa on the (110)[111] slip system, how much stress must be applied in the [001] direction to initiate slip?", "conversion_reason": "The answer is a definitive statement that can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip cannot be initiated in this direction no matter how much stress is applied", "B": "103.9 MPa (using Schmid factor calculation for [001] direction)", "C": "120 MPa (assuming double the critical resolved shear stress is needed)", "D": "60 MPa (assuming isotropic critical resolved shear stress)" }, "correct_answer": "A", "explanation": "The correct answer is A because the [001] direction is perpendicular to the (110) slip plane, resulting in a Schmid factor of zero. No resolved shear stress can be generated in this geometry regardless of applied stress. Option B is a cognitive bias trap that incorrectly applies Schmid factor mathematics without considering geometric constraints. Option C exploits the common misconception that higher stresses can overcome geometric limitations. Option D plays on the false intuition that critical resolved shear stress is direction-independent.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4921, "question": "The magnetic flux density within a bar of some material is 0.630 tesla at an H field of 5 x 10^5 A/m. Compute the magnetic permeability for this material.", "answer": "1.260 x 10^-6 h/m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（磁通密度与磁场强度的关系）来求解磁导率，答案是一个具体的数值结果。 | 知识层次: 题目要求计算磁导率，仅需应用基本公式（B = μH）进行一步计算，无需多步推理或综合分析。 | 难度: 在选择题中属于最低难度，仅需直接套用磁导率的基本公式（μ = B/H）并进行简单计算即可得出结果，无需额外的概念理解或步骤组合。", "convertible": true, "correct_option": "1.260 x 10^-6 h/m", "choice_question": "The magnetic flux density within a bar of some material is 0.630 tesla at an H field of 5 x 10^5 A/m. What is the magnetic permeability for this material?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.260 x 10^-6 H/m", "B": "1.260 x 10^-6 T·m/A", "C": "1.260 x 10^-3 H/m", "D": "1.260 x 10^-3 T·m/A" }, "correct_answer": "A", "explanation": "The correct answer is A because magnetic permeability (μ) is calculated as μ = B/H = 0.630 T / (5 x 10^5 A/m) = 1.260 x 10^-6 H/m. Option B uses the correct value but wrong unit (T·m/A is equivalent to H/m but not standard). Option C and D are incorrect due to magnitude errors (10^-3 instead of 10^-6), exploiting common unit conversion mistakes in material property calculations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1108, "question": "Interstitial compound", "answer": "Interstitial compound: When small solute atoms such as C, H, O, N, etc. are distributed in the interstices of the solvent atomic structure, altering the crystal structure of the solvent atoms, and the composition can generally be represented by a chemical formula, such a phase is called an interstitial compound.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Interstitial compound\"进行文字解释和论述，答案提供了详细的定义和特征描述，符合简答题的特点。 | 知识层次: 题目考查对间隙化合物（interstitial compound）这一基本概念的定义和特征的理解和记忆，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目属于概念解释和描述难度。虽然题目涉及基础概念记忆，但正确选项提供了较为详细的定义和例子，需要考生对间隙化合物的定义和特征有一定的理解和记忆。相比于仅要求基本定义简答的等级1题目，该题目对知识点的掌握深度要求更高，但不需要进行复杂的概念体系阐述或比较分析。", "convertible": true, "correct_option": "Interstitial compound: When small solute atoms such as C, H, O, N, etc. are distributed in the interstices of the solvent atomic structure, altering the crystal structure of the solvent atoms, and the composition can generally be represented by a chemical formula, such a phase is called an interstitial compound.", "choice_question": "Which of the following correctly describes an interstitial compound?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial compound: When small solute atoms such as C, H, O, N, etc. are distributed in the interstices of the solvent atomic structure, altering the crystal structure of the solvent atoms, and the composition can generally be represented by a chemical formula, such a phase is called an interstitial compound.", "B": "Interstitial compound: A phase formed when solute atoms replace solvent atoms in the crystal lattice, creating a substitutional solid solution with variable composition.", "C": "Interstitial compound: A metastable phase where interstitial atoms cause severe lattice distortion but do not form a defined chemical compound.", "D": "Interstitial compound: A composite material formed by mechanical mixing of two phases where one phase occupies the pores of the other." }, "correct_answer": "A", "explanation": "Correct answer A precisely defines interstitial compounds as small atoms occupying interstices while forming a defined chemical phase. Option B incorrectly describes substitutional solid solutions. Option C confuses interstitial compounds with interstitial solid solutions. Option D mistakenly associates interstitial compounds with composite materials, exploiting surface-level similarity in 'filling spaces'.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3565, "question": "The dislocations that can undergo cross-slip must be (). \\n\\nA. Edge dislocation B. Screw dislocation C. Mixed dislocation", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项A、B、C中选择正确答案，符合选择题的特征 | 知识层次: 题目考查位错类型及其特性的基本概念记忆，属于对screw dislocation能够进行cross-slip这一特性的直接认知。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（位错类型），但需要学生对不同类型的位错（刃型位错、螺型位错、混合位错）有明确的理解和区分能力。特别是要理解为什么只有螺型位错能够进行交滑移，这需要一定的概念辨析能力，而非简单的记忆。因此属于等级2难度。", "convertible": true, "correct_option": "B. Screw dislocation", "choice_question": "The dislocations that can undergo cross-slip must be ().", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Edge dislocation with high Peierls stress", "B": "Screw dislocation in FCC crystals", "C": "Mixed dislocation with 60° character", "D": "Screw dislocation in BCC crystals at 0.6Tm" }, "correct_answer": "B", "explanation": "The correct answer is B because screw dislocations in FCC crystals can undergo cross-slip due to their non-planar core structure and the availability of multiple slip planes. Option A is incorrect because edge dislocations cannot cross-slip regardless of Peierls stress. Option C is a cognitive bias trap, as mixed dislocations cannot fully cross-slip despite their screw component. Option D exploits professional intuition by using BCC crystals at high temperatures, where cross-slip is possible but requires specific thermal activation conditions not mentioned here.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 85, "question": "Explain the meaning of the symbol Ca_{Ca}", "answer": "Ca atom located at the Ca atom site", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释符号的含义，需要文字解释和论述，答案也是以文字形式呈现的解释性内容 | 知识层次: 题目考查对晶体缺陷符号的基本概念记忆和理解，属于基础概念层次 | 难度: 在选择题型中，该题目仅要求识别并记忆基础符号的定义（Ca atom located at the Ca atom site），属于直接回忆型知识点，无需解释或推理步骤，符合等级1“基本定义简答”的标准。", "convertible": true, "correct_option": "Ca atom located at the Ca atom site", "choice_question": "What is the meaning of the symbol Ca_{Ca}?", "conversion_reason": "The answer is a standard term or concept, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Ca atom located at the Ca atom site", "B": "Calcium vacancy in the crystal lattice", "C": "Interstitial calcium atom", "D": "Calcium substitutional defect" }, "correct_answer": "A", "explanation": "The correct answer is A because the notation X_Y represents an atom X occupying the site normally occupied by atom Y in the crystal structure. Option B exploits the common confusion with vacancy notation (V_Y). Option C targets the misconception about interstitial positions. Option D creates confusion by suggesting a substitutional defect, which would require a different element replacing Ca.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1246, "question": "According to the phase rule, what is the maximum number of equilibrium phases in a binary system represented on the phase diagram?", "answer": "19", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目涉及相律的应用和数值计算，需要根据相律公式（F = C - P + 2）进行计算得出最大平衡相数，答案是一个具体数值（19），属于计算题特征。 | 知识层次: 题目考查对相律公式的直接应用，需要简单的数值计算，属于基本公式应用和简单计算范畴。虽然涉及相律这一基础概念，但主要考察的是对公式的理解和直接套用能力，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于最低难度等级。题目直接考察对相律公式（F = C - P + 2）的简单应用，只需将二元系统条件（C=2）代入公式并计算最大相数（F=0时）。解题过程仅需一步公式代入和基本算术运算，完全符合等级1\"单一公式直接计算\"的标准。选择题型中这种直接套用基础公式的题目属于最基础难度。", "convertible": true, "correct_option": "19", "choice_question": "According to the phase rule, what is the maximum number of equilibrium phases in a binary system represented on the phase diagram?", "conversion_reason": "The question is a calculation question with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项C", "B": "选项B", "C": "选项D", "D": "19" }, "correct_answer": "D", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 4364, "question": "What is the driving force for the formation of spheroidite?", "answer": "The driving force for the formation of spheroidite is the net reduction in ferrite-cementite phase boundary area.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释spheroidite形成的驱动力，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对spheroidite形成驱动力的基本概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并准确回忆spheroidite形成的驱动力，即铁素体-渗碳体相界面积的净减少。这比简单的定义记忆（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。", "convertible": true, "correct_option": "The net reduction in ferrite-cementite phase boundary area", "choice_question": "What is the driving force for the formation of spheroidite?", "conversion_reason": "The answer is a standard concept or term, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The net reduction in ferrite-cementite phase boundary area", "B": "The minimization of interfacial energy through curvature effects", "C": "The reduction in dislocation density during annealing", "D": "The thermodynamic instability of lamellar cementite" }, "correct_answer": "A", "explanation": "The correct answer is A because spheroidite formation is primarily driven by the reduction in total interfacial area between ferrite and cementite phases, which lowers the overall system energy. Option B is a strong distractor as it partially describes a mechanism but focuses incorrectly on curvature effects rather than total boundary area reduction. Option C exploits the common association between annealing and dislocation reduction, which is irrelevant to the phase boundary driving force. Option D uses a technically correct statement about cementite instability but misattributes it as the primary driving force rather than a contributing factor.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1733, "question": "What is a modifier?", "answer": "A substance that can change the phase composition, phase morphology, or grain size of an alloy's as-cast structure by adding a small amount, thereby altering the properties of the cast alloy, is called a modifier.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对“modifier”进行定义和解释，答案提供了详细的文字描述，符合简答题的特征。 | 知识层次: 题目考查对\"modifier\"这一基本概念的定义和作用的记忆和理解，属于基础概念记忆性知识。 | 难度: 在选择题型中，该题目仅要求识别和记忆“modifier”的基本定义，属于最基础的概念记忆层次。正确选项直接给出了定义，无需进行复杂的概念比较或分析，符合等级1“基本定义简答”的标准。", "convertible": true, "correct_option": "A substance that can change the phase composition, phase morphology, or grain size of an alloy's as-cast structure by adding a small amount, thereby altering the properties of the cast alloy, is called a modifier.", "choice_question": "Which of the following best defines a modifier?", "conversion_reason": "The original question is a short answer question asking for a definition, which can be converted into a multiple-choice question by providing the definition as the correct option and rephrasing the question to ask for the best definition among choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A substance that can change the phase composition, phase morphology, or grain size of an alloy's as-cast structure by adding a small amount, thereby altering the properties of the cast alloy", "B": "An element added to alloys to increase their elastic modulus by forming secondary phases", "C": "A processing technique used to refine grain structure through rapid solidification", "D": "A dopant that modifies the electronic structure of semiconductors by introducing energy levels in the band gap" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines a modifier in metallurgy, focusing on its role in altering as-cast structures. Option B exploits cognitive bias by confusing modifiers with strengthening elements, using the familiar concept of elastic modulus. Option C is a professional intuition trap, mimicking grain refinement but describing a processing method rather than an additive. Option D is a multi-level trap, correctly describing doping in semiconductors but inappropriately applying it to alloy modification.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3752, "question": "Calculate the fraction of solidification that occurs dendritically when iron nucleates homogeneously. The specific heat of iron is 5.78 J/cm^3·°C.", "answer": "all dendritically.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释铁均匀成核时枝晶凝固的比例，答案需要文字解释而非计算或选择 | 知识层次: 题目主要考查对凝固过程中枝晶形成这一基本概念的理解和记忆，不需要复杂的计算或分析过程。 | 难度: 在选择题型中，该题目仅要求记忆基本原理（铁均匀形核时全部以枝晶方式凝固），无需复杂分析或计算步骤。正确选项直接对应基础概念记忆层次，属于最简单的选择题难度等级。", "convertible": true, "correct_option": "all dendritically", "choice_question": "When iron nucleates homogeneously, the fraction of solidification that occurs dendritically is:", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "all dendritically", "B": "50% dendritically and 50% planar", "C": "only the initial 10% occurs dendritically", "D": "depends on the cooling rate" }, "correct_answer": "A", "explanation": "The correct answer is A because homogeneous nucleation in pure iron always leads to completely dendritic solidification due to constitutional supercooling. Option B is a cognitive bias trap, suggesting an equal split that seems reasonable but ignores metallurgical principles. Option C exploits the common misconception that initial solidification differs from later stages. Option D is a professional intuition trap, as cooling rate affects dendrite spacing but not the fundamental dendritic nature of solidification in this case.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1631, "question": "What are the main resistances to nucleation in solid-state phase transformations?", "answer": "Interfacial energy and elastic strain energy", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和列举固态相变中成核的主要阻力，答案以文字形式给出，需要简要说明和论述 | 知识层次: 题目考查固态相变中成核的主要阻力，即界面能和弹性应变能，属于基础概念的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生同时掌握\"界面能\"和\"弹性应变能\"这两个关键概念，并理解它们对固态相变中形核阻力的影响。这比单纯记忆单一概念的定义（等级1）要求更高，但又不涉及复杂的概念体系分析（等级3）。", "convertible": true, "correct_option": "Interfacial energy and elastic strain energy", "choice_question": "What are the main resistances to nucleation in solid-state phase transformations?", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by providing options including the correct answer and plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interfacial energy and elastic strain energy", "B": "Activation energy and lattice mismatch", "C": "Dislocation density and stacking fault energy", "D": "Bulk modulus and thermal expansion coefficient" }, "correct_answer": "A", "explanation": "The correct answer is A because interfacial energy creates a barrier for new phase formation, and elastic strain energy arises from lattice distortion during nucleation. Option B is tempting as activation energy is a general nucleation concept, but it's not specific to solid-state transformations. Option C uses real material parameters that affect deformation but not nucleation directly. Option D employs bulk material properties that seem relevant but don't represent nucleation resistances.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 261, "question": "In the fabrication of silicon semiconductor devices, boron is often diffused into silicon single crystals. If at a temperature of 1600K, the boron concentration on the surface of the silicon single crystal is kept constant (constant source semi-infinite diffusion), and the boron concentration at a depth of $10^{-3}\\\\mathrm{cm}$ from the surface is required to be half of the surface concentration (erfc =0.5 $\\\\frac{x}{2\\\\sqrt{D t}}$ 0.5), how long is needed (given $\\\\boldsymbol{D_{1600^{*}C}}=8\\\\times10^{-12}\\\\mathrm{{cm}^{2}/{s}}$ when 2√Dt, 2√D# )?", "answer": "This model can be regarded as a one-dimensional diffusion problem of a semi-infinite rod, which can be solved using the Gaussian error function. $\\\\frac{C_{0}-C}{C_{0}-C_{1}}=\\\\mathrm{erf}(\\\\frac{x}{2\\\\sqrt{D t}})$ where $\\\\mathcal{C}_{1\\\\mathrm{~=~}0}$, $C=0.5C_{0}$, so there is $\\\\cot(\\\\frac{x}{2\\\\sqrt{D t}})$, 2=0.5. Substituting $x=10^{-3}\\\\mathrm{cm}$ and $D=8\\\\times10^{-12}\\\\mathrm{{cm}^{2}/\\\\mathrm{{s}}}$ yields $t=1.25\\\\times10^{5}\\\\mathrm{~s~}$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，涉及扩散方程和误差函数的计算，最终需要得出具体的时间数值。 | 知识层次: 题目涉及扩散方程的求解和误差函数的应用，需要多步计算和概念关联，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解半导体扩散的基本概念（如恒定源半无限扩散模型），正确应用误差函数（erf）公式，并进行多步骤的代数运算和单位换算。题目涉及中等应用层次的知识，要求考生能够将扩散系数、浓度分布和时间计算等概念关联起来，综合分析求解。虽然题目提供了关键公式和参数，但解题过程仍需较强的逻辑推导和计算能力，属于综合性计算问题。", "convertible": true, "correct_option": "1.25×10^5 s", "choice_question": "In the fabrication of silicon semiconductor devices, boron is often diffused into silicon single crystals. If at a temperature of 1600K, the boron concentration on the surface of the silicon single crystal is kept constant (constant source semi-infinite diffusion), and the boron concentration at a depth of 10^-3 cm from the surface is required to be half of the surface concentration (erfc =0.5 x/(2√Dt) = 0.5), how long is needed (given D_1600°C = 8×10^-12 cm²/s)?", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format with the correct option being the calculated time.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.25×10^5 s", "B": "6.25×10^4 s", "C": "2.50×10^5 s", "D": "3.13×10^4 s" }, "correct_answer": "A", "explanation": "The correct answer is derived from solving the diffusion equation for constant surface concentration (erfc function). Given erfc(z)=0.5 when z≈0.477, we set x/(2√Dt)=0.477. With x=10^-3 cm and D=8×10^-12 cm²/s, solving for t gives 1.25×10^5 s. Option B is half the correct value, exploiting a common factor-of-2 error in diffusion calculations. Option C is double the correct value, targeting those who misapply the square root relationship. Option D is 1/4 of the correct value, preying on confusion with the x²/Dt term in diffusion equations.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4251, "question": "The diffusion coefficients for iron in nickel are given at two temperatures: 1273 K with D = 9.4 x 10^-16 m^2/s and 1473 K with D = 2.4 x 10^-14 m^2/s. What is the magnitude of D at 1100°C (1373 K)?", "answer": "the magnitude of d at 1100°c (1373 k) is 5.4 x 10^-15 m^2/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的扩散系数和温度数据，应用阿伦尼乌斯方程或其他相关公式进行计算，以得出在特定温度下的扩散系数。答案是一个具体的数值结果，需要通过计算步骤得出。 | 知识层次: 题目需要应用扩散系数的阿伦尼乌斯公式进行多步计算，包括求解活化能和预指数因子，然后计算新的温度下的扩散系数。这涉及到对公式的理解和综合应用，属于中等难度的应用题目。 | 难度: 在选择题中属于中等难度，需要理解扩散系数的温度依赖性（阿伦尼乌斯方程），进行多步计算（求解活化能和指前因子），并应用这些参数计算新温度下的扩散系数。虽然题目提供了部分数据，但解题过程涉及多个概念的综合运用和数学计算步骤。", "convertible": true, "correct_option": "5.4 x 10^-15 m^2/s", "choice_question": "The diffusion coefficients for iron in nickel are given at two temperatures: 1273 K with D = 9.4 x 10^-16 m^2/s and 1473 K with D = 2.4 x 10^-14 m^2/s. What is the magnitude of D at 1100°C (1373 K)?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "5.4 x 10^-15 m^2/s", "B": "2.4 x 10^-14 m^2/s", "C": "9.4 x 10^-16 m^2/s", "D": "1.7 x 10^-14 m^2/s" }, "correct_answer": "A", "explanation": "正确答案A是通过Arrhenius方程正确计算得到的扩散系数值。干扰项B直接使用了1473K的数据，利用了AI可能忽略温度差异的认知偏差。干扰项C直接使用了1273K的数据，是典型的'第一印象'陷阱。干扰项D设计为接近正确答案但指数错误的数值，利用了单位数量级的直觉判断弱点。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3895, "question": "The electrons that occupy the outermost filled shell are called electrons.", "answer": "The electrons that occupy the outermost filled shell are called valence electrons.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的术语（valence electrons），属于需要简短文字回答的简答题类型 | 知识层次: 题目考查基本概念的记忆和理解，即对价电子（valence electrons）的定义的记忆。 | 难度: 在选择题型中，该题目仅考察基础概念的记忆，即\"valence electrons\"的定义。题目直接给出了定义描述，只需选择正确的术语填空，无需任何解释或复杂分析步骤。这属于最基本的知识点掌握要求，符合等级1的标准。", "convertible": true, "correct_option": "valence electrons", "choice_question": "The electrons that occupy the outermost filled shell are called:", "conversion_reason": "The answer is a standard term (valence electrons), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "valence electrons", "B": "conduction electrons", "C": "core electrons", "D": "hybridized electrons" }, "correct_answer": "A", "explanation": "The correct answer is A because valence electrons are defined as the electrons in the outermost shell of an atom that participate in chemical bonding. Option B (conduction electrons) is a trap for AI models as these are specifically free electrons in metals that conduct electricity, not necessarily the outermost electrons. Option C (core electrons) exploits the common confusion with inner shell electrons that don't participate in bonding. Option D (hybridized electrons) is a sophisticated trap that references a real quantum mechanical phenomenon but incorrectly applies it to basic electron shell terminology.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2148, "question": "For a pre-annealed metal polycrystal, the relationship between true stress σ_T and true strain ε_T in the uniform plastic deformation stage of the true stress-strain curve is given by σ_T=Kε_T^n, where K is the strength coefficient and n is the strain hardening exponent. If there are two metals A and B with roughly equal K values, but n_A=0.5 and n_B=0.2, which metal has higher hardening capability and why?", "answer": "Since σ_T=Kε_T^n, then dσ_T=n Kε_T^(n-1)dε_T, and θ=dσ_T/dε_T=n Kε_T^(n-1). From this equation, it can be seen that when ε_T<1 and 0 slip in FCC metals at 0K", "B": "The Peierls-Nabarro stress for {110}<111> slip in BCC metals at 0K", "C": "The theoretical shear strength of a perfect crystal (G/2π)", "D": "The Orowan stress for dislocation bypassing nanoscale precipitates" }, "correct_answer": "B", "explanation": "Correct answer is B because the Peierls-Nabarro stress represents the intrinsic lattice resistance to dislocation motion in BCC metals at 0K. A is incorrect (cognitive bias) as it describes a specific slip system activation stress. C is a trap (professional intuition) as G/2π is the ideal strength, not actual slip resistance. D exploits verification complexity by introducing a real but irrelevant strengthening mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3053, "question": "The porosity of thermal insulation material is (3). A.5%~10% B.<5% C.<0.5% D.>10%", "answer": "(3)D", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项中选择正确答案 | 知识层次: 题目考查对热绝缘材料孔隙率范围的基础概念记忆，属于定义性知识的直接回忆。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需直接回忆热绝缘材料的孔隙率范围即可选择正确答案。选项之间的区分度明显，无需复杂分析或深度理解，符合等级1的简单概念识别标准。", "convertible": true, "correct_option": "D.>10%", "choice_question": "The porosity of thermal insulation material is", "conversion_reason": "原题目已经是单选题格式，可以直接转换。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The Hall-Petch relationship applies to nanocrystalline materials with grain sizes below 10nm", "B": "The inverse Hall-Petch effect occurs due to increased dislocation activity at ultra-fine grain sizes", "C": "Grain boundary sliding becomes the dominant deformation mechanism below 100nm grain size", "D": "The critical grain size for inverse Hall-Petch behavior is material-independent" }, "correct_answer": "C", "explanation": "Correct answer is C because grain boundary sliding indeed becomes dominant when grain sizes fall below ~100nm. Option A is a cognitive bias trap - while Hall-Petch breaks down at nanoscale, the exact threshold varies by material. Option B reverses causality - inverse Hall-Petch is due to reduced dislocation activity. Option D is a professional intuition trap - the critical size actually depends on stacking fault energy and other material properties.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 200, "question": "The eutectic of the MgO-Al2O3-SiO2 system is placed on a Si3N4 ceramic plate. At the eutectic temperature, the surface tension of the liquid phase is 900 mN/m, the interfacial energy between the liquid and solid is 600 mN/m, and the measured contact angle is 70.52°. Find the surface tension of Si3N4.", "answer": "Yv = Ycosθ + Y = 900cos70.52° + 600 = 900 mN/m", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解Si3N4的表面张力，答案给出了具体的计算过程和数值结果。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即使用表面张力和接触角的公式进行直接计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。题目直接给出了所需的公式（Yv = Ycosθ + Y），并且只需要进行简单的代入和计算（代入θ=70.52°和给定的表面张力值）。虽然涉及到了接触角和表面张力的概念，但解题步骤非常直接，无需复杂的推导或分析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "900 mN/m", "choice_question": "The eutectic of the MgO-Al2O3-SiO2 system is placed on a Si3N4 ceramic plate. At the eutectic temperature, the surface tension of the liquid phase is 900 mN/m, the interfacial energy between the liquid and solid is 600 mN/m, and the measured contact angle is 70.52°. What is the surface tension of Si3N4?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "900 mN/m", "B": "600 mN/m", "C": "1200 mN/m", "D": "300 mN/m" }, "correct_answer": "A", "explanation": "The correct answer is A (900 mN/m) because it is derived from Young's equation: γ_s = γ_l*cosθ + γ_sl, where γ_s is the surface tension of Si3N4, γ_l is the liquid surface tension (900 mN/m), θ is the contact angle (70.52°), and γ_sl is the interfacial energy (600 mN/m). The calculation gives γ_s = 900 mN/m. Option B (600 mN/m) is a cognitive bias trap, directly using the interfacial energy value. Option C (1200 mN/m) exploits the common mistake of adding instead of properly applying the cosine function. Option D (300 mN/m) is designed to catch those who might subtract values incorrectly without considering the trigonometric relationship.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1004, "question": "Please analyze the characteristics and mechanisms of dispersion strengthening (age strengthening).", "answer": "Dispersion strengthening (age strengthening): It is the strengthening caused by fine dispersed second phases hindering dislocation motion. This includes the shearing mechanism and the bypassing mechanism.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求分析分散强化（时效强化）的特性和机制，需要文字解释和论述，答案也提供了详细的文字描述，符合简答题的特征。 | 知识层次: 题目要求分析弥散强化（时效强化）的特性和机制，涉及对位错运动的阻碍机制（剪切机制和绕过机制）的解释，需要综合运用材料科学中的强化机制知识，进行机理层面的分析和解释，属于较高层次的认知要求。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生不仅理解分散强化（时效强化）的基本概念，还需要掌握其背后的两种具体机制（剪切机制和绕过机制），并能准确区分和描述这些机制如何阻碍位错运动。这需要考生具备深入的材料科学知识，能够进行复杂现象的综合分析，并准确解释机理。这种题目在选择题型中属于对知识掌握深度和综合分析能力要求极高的类型。", "convertible": true, "correct_option": "It is the strengthening caused by fine dispersed second phases hindering dislocation motion. This includes the shearing mechanism and the bypassing mechanism.", "choice_question": "Which of the following best describes the characteristics and mechanisms of dispersion strengthening (age strengthening)?", "conversion_reason": "The answer is a standard concept and can be converted into a multiple-choice question format by asking for the best description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "It is the strengthening caused by fine dispersed second phases hindering dislocation motion. This includes the shearing mechanism and the bypassing mechanism.", "B": "It is the strengthening caused by solute atoms distorting the crystal lattice, where the size difference between solute and solvent atoms is the key factor.", "C": "It is the strengthening caused by grain boundary obstruction of dislocation motion, following the Hall-Petch relationship for grain size dependence.", "D": "It is the strengthening caused by dislocation entanglement and forest dislocation interactions, where dislocation density is the primary controlling factor." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes dispersion strengthening (age strengthening) which involves second phase particles impeding dislocation motion through either shearing or bypassing mechanisms. Option B describes solid solution strengthening, not dispersion strengthening. Option C describes grain boundary strengthening, a completely different mechanism. Option D describes work hardening, another distinct strengthening mechanism. These distractors exploit common confusion between different material strengthening mechanisms that all involve dislocation motion but through fundamentally different approaches.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1448, "question": "Compared to pure iron, how do the plasticity and toughness of ferrite change?", "answer": "Lower", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释ferrite的塑性和韧性相对于纯铁的变化情况，需要文字解释和论述，而不是简单的选择或判断 | 知识层次: 题目考查对纯铁和铁素体塑性及韧性差异的基础概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，此题仅涉及基础概念记忆，要求考生回忆纯铁与铁素体在塑性和韧性方面的差异。题目仅提供正确选项\"Lower\"，无需复杂分析或推理，属于最基本的概念性知识考察。", "convertible": true, "correct_option": "Lower", "choice_question": "Compared to pure iron, how do the plasticity and toughness of ferrite change?", "conversion_reason": "The answer is a standard term that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Higher due to reduced dislocation density", "B": "Lower due to carbon interstitial strengthening", "C": "Unchanged as both are BCC structures", "D": "Higher only under dynamic loading conditions" }, "correct_answer": "B", "explanation": "The correct answer is B because ferrite, while being a nearly pure iron phase, contains small amounts of carbon in interstitial positions which create lattice distortions and reduce plasticity and toughness compared to pure iron. Option A is a cognitive bias trap - while reduced dislocation density would theoretically increase plasticity, this doesn't apply to the ferrite-pure iron comparison. Option C exploits structural similarity misconception - though both have BCC structure, the carbon content makes the key difference. Option D creates a specific condition trap - dynamic loading doesn't reverse the fundamental property relationship.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2549, "question": "What are the main types of silicate structures?", "answer": "The main types of silicate structures can be classified according to the spatial arrangement of silicon-oxygen tetrahedra into: island, chain, sheet, and framework.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和列举硅酸盐结构的主要类型，答案以文字叙述形式给出，不需要计算或选择选项 | 知识层次: 题目考查对硅酸盐结构基本分类的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然涉及的是基础概念记忆（硅酸盐结构的分类），但需要考生准确回忆并区分四种不同的空间排列方式（岛状、链状、片状和架状）。这比单纯记忆单一定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。选择题型中，这类题目通常表现为让考生从选项中识别正确的分类描述，属于概念解释和描述的难度层级。", "convertible": true, "correct_option": "island, chain, sheet, and framework", "choice_question": "What are the main types of silicate structures classified according to the spatial arrangement of silicon-oxygen tetrahedra?", "conversion_reason": "The answer is a standard list of terms that can be presented as options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Island, chain, sheet, and framework", "B": "Linear, planar, cubic, and amorphous", "C": "Primary, secondary, tertiary, and quaternary", "D": "Monomeric, dimeric, polymeric, and cross-linked" }, "correct_answer": "A", "explanation": "The correct answer is A because silicate structures are classified based on the spatial arrangement of silicon-oxygen tetrahedra into island (isolated tetrahedra), chain (linked tetrahedra in one dimension), sheet (linked tetrahedra in two dimensions), and framework (linked tetrahedra in three dimensions). Option B uses general structural descriptors not specific to silicates. Option C borrows protein structure terminology which is irrelevant. Option D describes polymerization degrees rather than spatial arrangements, exploiting chemical terminology confusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3846, "question": "For an Fe-0.35% C alloy, determine the temperature at which austenite first begins to transform on cooling.", "answer": "795°C", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求确定特定合金在冷却过程中奥氏体开始转变的温度，这需要参考铁碳相图或相关公式进行计算，答案以具体数值形式给出。 | 知识层次: 题目要求根据给定的合金成分（Fe-0.35% C）和铁碳相图，确定奥氏体开始转变的温度。这主要涉及基本公式应用和直接套用铁碳相图的知识，不需要多步计算或复杂分析。 | 难度: 在选择题型内，该题目属于单一公式直接计算的难度等级。题目要求根据Fe-C相图直接查找或应用已知的相变温度数据，无需复杂计算或多步骤推理。学生只需记住或查阅0.35%碳含量对应的奥氏体开始转变温度即可得出正确答案795°C。这属于基础知识的直接应用，符合等级1的定义。", "convertible": true, "correct_option": "795°C", "choice_question": "For an Fe-0.35% C alloy, at what temperature does austenite first begin to transform on cooling?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "795°C", "B": "727°C", "C": "850°C", "D": "680°C" }, "correct_answer": "A", "explanation": "The correct answer is 795°C as this is the A3 temperature for Fe-0.35%C alloy where austenite first begins to transform to ferrite on cooling. Option B (727°C) is the eutectoid temperature, a common trap for those confusing the start of transformation with the eutectoid reaction. Option C (850°C) exploits the misconception that higher carbon content raises all transformation temperatures. Option D (680°C) targets those who might mistake this for a high-alloy steel's transformation temperature.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1895, "question": "Wetting is an important behavior at the solid-liquid interface, one of the methods to improve wetting is (17)", "answer": "Increase the surface energy of the solid (remove the adsorbed film on the solid surface)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释改善润湿行为的方法，答案需要文字解释和论述，而不是从选项中选择或简单的对错判断。 | 知识层次: 题目考查对润湿行为及其改善方法的基本概念记忆和理解，属于基础知识的直接应用，不涉及复杂分析或综合推理。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需考生记住改善润湿的一种方法即可。题目直接给出了正确选项，没有涉及复杂的概念体系或需要解释和描述的内容。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "Increase the surface energy of the solid (remove the adsorbed film on the solid surface)", "choice_question": "Wetting is an important behavior at the solid-liquid interface. One of the methods to improve wetting is:", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increase the surface energy of the solid (remove the adsorbed film on the solid surface)", "B": "Decrease the viscosity of the liquid to enhance spreading kinetics", "C": "Increase the contact angle to promote capillary action", "D": "Reduce the interfacial tension by adding surfactants to both phases" }, "correct_answer": "A", "explanation": "The correct answer is A because increasing the solid's surface energy directly improves wettability by reducing the contact angle according to Young's equation. Option B exploits kinematic intuition but viscosity only affects spreading rate, not equilibrium wettability. Option C reverses the fundamental relationship - larger contact angles indicate poorer wetting. Option D creates a multi-variable trap by suggesting simultaneous modification of both phases, when in reality surfactant adsorption preferentially occurs at interfaces.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2560, "question": "If a single crystal aluminum rod with a diameter of $5mm$ starts to slip when a tensile force of 40N is applied along the rod axis [123], find the critical resolved shear stress of aluminum during slipping.", "answer": "Single crystal aluminum has an FCC structure, and the slip system is {111}<110>. Using the imaging rule, the slip plane and slip direction are determined to be (11)[101]. The angles between them and the axis are respectively: $$ \\begin{array}{r l}&{\\mathtt{cos}\\Phi=\\left[123\\right]\\bullet[\\overline{{1}}11]/(\\left|\\left[123\\right]\\right|\\left[\\overline{{1}}11\\right]|)=4/\\surd42;}\\ &{\\mathtt{cos}\\mathtt{\\lambda}=\\left[123\\right]\\bullet[101]/(\\left|\\left[123\\right]\\right|\\left[101\\right]|)=2/\\surd7;}\\end{array} $$ Therefore, the critical resolved shear stress τc = $\\mathsf{\\bar{cos}\\lambda cos\\Phi/A_{0}=\\lambda\\cdots=0.95MPa}.$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解临界分切应力，解答过程中涉及角度计算、应力公式应用和具体数值代入，属于典型的计算题。 | 知识层次: 题目需要进行多步计算，包括确定滑移面和滑移方向、计算角度、应用临界分切应力公式等。同时需要理解FCC结构的滑移系统概念和成像规则，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、滑移系统、成像规则等概念，并进行多步计算（包括向量点积、角度计算、应力公式应用等）。虽然题目提供了部分计算步骤，但仍要求考生具备较强的综合分析能力和计算准确性。", "convertible": true, "correct_option": "0.95MPa", "choice_question": "If a single crystal aluminum rod with a diameter of $5mm$ starts to slip when a tensile force of 40N is applied along the rod axis [123], what is the critical resolved shear stress of aluminum during slipping?", "conversion_reason": "The answer is a specific numerical value (0.95MPa), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.95MPa", "B": "1.23MPa", "C": "2.04MPa", "D": "3.56MPa" }, "correct_answer": "A", "explanation": "The correct answer is A (0.95MPa) because the critical resolved shear stress is calculated using the Schmid factor for the [123] direction in aluminum. Option B (1.23MPa) is designed to exploit the common mistake of using the wrong slip system or incorrect angle calculation. Option C (2.04MPa) is based on the error of using the full tensile stress without considering the resolved shear component. Option D (3.56MPa) is a trap for those who might confuse the shear stress with the elastic modulus or yield strength of aluminum.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4283, "question": "What is the difference between deformation by twinning and deformation by slip relative to final result?", "answer": "Normally slip results in relatively large deformations, whereas only small deformations result for twinning.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两种变形方式的区别，答案需要文字论述而非选择、判断或计算。 | 知识层次: 题目考查变形孪生和滑移变形的基本概念及其最终结果的差异，属于基础概念的记忆和理解范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（变形孪生和滑移的区别），但需要考生理解并比较两种变形机制的最终结果差异。正确选项明确指出了两种机制在变形程度上的区别，这要求考生不仅要记住定义，还要能够区分和描述两者的特征。相比单纯记忆定义（等级1），这种比较性描述需要更深一层的概念理解，但尚未达到需要分析复杂概念体系的等级3难度。", "convertible": true, "correct_option": "Normally slip results in relatively large deformations, whereas only small deformations result for twinning.", "choice_question": "What is the difference between deformation by twinning and deformation by slip relative to final result?", "conversion_reason": "The answer is a standard description that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Slip results in relatively large deformations, whereas twinning produces only small deformations", "B": "Twinning causes permanent lattice distortion while slip preserves crystal symmetry", "C": "Slip requires higher activation energy but leads to more uniform deformation than twinning", "D": "Both mechanisms produce equivalent strain but twinning occurs at lower temperatures" }, "correct_answer": "A", "explanation": "Correct answer A directly states the fundamental difference in deformation magnitude between the two mechanisms. Option B reverses the actual symmetry effects (twinning preserves symmetry while slip distorts it). Option C mixes truth (slip's higher activation energy) with falsehood (uniformity claim). Option D's temperature claim is misleading as both can occur across temperature ranges, and their strain equivalence is false.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2786, "question": "A carbon steel with w(C)=0.1% is carburized at 930°C, reaching a carbon concentration of 0.45% at a depth of 0.05cm. For all times t>0, the carburizing atmosphere maintains a surface composition of 1%. Assuming D=0.2×10^(-5) exp(-140000/RT)(m²/s), calculate the carburizing time.", "answer": "From Fick's second law, the solution is w=w_s-(w_s-w_0)erf(x/(2√(Dt))). Substituting the data gives (1%-0.45%)/(1%-0.1%)=erf(0.05/(2√(Dt))), i.e., 0.61=erf(0.05/(2√(Dt))). Looking up the table yields 0.05/(2√(Dt))=0.61, and D=0.2×exp(-140000/(8.314×1203))=1.67×10^(-7)(cm²/s). Therefore, the carburizing time t≈1.0×10^3(s).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及Fick第二定律的解析解和误差函数的使用，最终需要计算出具体的渗碳时间。答案中包含了详细的数学推导和数值代入过程，符合计算题的特征。 | 知识层次: 题目需要应用Fick第二定律进行多步计算，包括查表、数值代入和单位转换等操作，涉及扩散系数的计算和误差函数的应用，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要综合运用菲克第二定律、误差函数查表、温度换算和扩散系数计算等多个步骤。虽然题目提供了关键公式和数据，但解题过程涉及多个概念关联和计算环节，包括查表换算和单位转换，对学生的综合分析能力有一定要求。", "convertible": true, "correct_option": "1.0×10^3(s)", "choice_question": "A carbon steel with w(C)=0.1% is carburized at 930°C, reaching a carbon concentration of 0.45% at a depth of 0.05cm. For all times t>0, the carburizing atmosphere maintains a surface composition of 1%. Assuming D=0.2×10^(-5) exp(-140000/RT)(m²/s), the carburizing time is approximately:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a single correct option among multiple choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.0×10^3(s)", "B": "2.5×10^3(s)", "C": "5.0×10^2(s)", "D": "1.5×10^3(s)" }, "correct_answer": "A", "explanation": "正确答案A是通过菲克第二定律精确计算得出的，考虑了温度对扩散系数的影响。干扰项B利用了常见的时间估算偏差，将计算结果简单乘以2.5倍。干扰项C通过减半计算时间制造直觉陷阱，忽略了扩散过程的非线性特性。干扰项D设计为接近但略高于正确答案的数值，利用'中庸选择'的心理倾向。所有干扰项都针对AI模型在材料科学计算中常见的数值敏感性和单位转换弱点设计。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4899, "question": "What is the magnitude of the voltage generated in an Fe/Fe2+ concentration cell with Fe2+ concentrations of 0.5 M and 2 × 10^-2 M?", "answer": "The magnitude of the voltage is 0.0414 V.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求计算Fe/Fe2+浓度电池中产生的电压大小，需要通过公式应用和数值计算得出具体数值的答案。答案给出了具体的电压值0.0414 V，这表明解答过程涉及计算步骤。 | 知识层次: 题目涉及基本的电化学公式应用（Nernst方程），只需要直接套用公式进行简单计算即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用能斯特方程来计算电压，但题目已经给出了明确的浓度值，只需要直接套用公式并进行简单的对数计算即可得出结果。不需要复杂的推导或多步骤的公式组合，因此难度等级为2。", "convertible": true, "correct_option": "0.0414 V", "choice_question": "What is the magnitude of the voltage generated in an Fe/Fe2+ concentration cell with Fe2+ concentrations of 0.5 M and 2 × 10^-2 M?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0414 V", "B": "0.0828 V", "C": "0.0207 V", "D": "0.0591 V" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the Nernst equation for a concentration cell: E = (0.0591 V/n) * log(C2/C1), where n=2 for Fe2+. Plugging in the values gives E = (0.0591/2)*log(0.5/0.02) = 0.0414 V. Option B incorrectly doubles the correct value. Option C uses half the correct value, a common error when misapplying the n factor. Option D presents the standard 0.0591 V value, which is the slope at 298K but not the actual cell potential in this case.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4350, "question": "Is it possible to determine the composition of an iron-carbon alloy if the mass fraction of eutectoid ferrite is 0.82?", "answer": "yes, it is possible to determine the alloy composition; and, in fact, there are two possible answers.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目需要解释和论述如何根据给定的质量分数确定铁碳合金的组成，答案提供了文字解释和可能的两种情况，符合简答题的特征。 | 知识层次: 题目需要应用铁碳相图的知识，通过给定的共析铁素体质量分数来计算合金的组成。这涉及到多步计算和概念关联，需要理解共析反应和杠杆定律的应用，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合运用铁碳相图知识、杠杆定律计算以及理解共析反应的概念。题目要求考生通过给定的共析铁素体质量分数反推合金成分，涉及多步计算和综合分析，且需要意识到存在两种可能的成分解（亚共析钢和过共析钢）。这种需要逆向思维和双重解意识的题目在选择题型中属于较复杂的考查方式。", "convertible": true, "correct_option": "yes, it is possible to determine the alloy composition; and, in fact, there are two possible answers.", "choice_question": "Is it possible to determine the composition of an iron-carbon alloy if the mass fraction of eutectoid ferrite is 0.82?", "conversion_reason": "The answer is a clear and definitive statement, which can be directly used as the correct option in a multiple-choice format. The question itself is already suitable for a multiple-choice format without needing significant rewording.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yes, the composition can be uniquely determined as 0.76 wt% C", "B": "No, the composition cannot be determined from this information alone", "C": "Yes, but there are two possible compositions (0.76 wt% C and 1.15 wt% C)", "D": "Only if the alloy is hypoeutectoid" }, "correct_answer": "C", "explanation": "The correct answer is C because the eutectoid ferrite fraction of 0.82 corresponds to two possible cases: 1) a hypoeutectoid alloy with composition below 0.76 wt% C where ferrite forms before the eutectoid reaction, and 2) a hypereutectoid alloy where primary cementite forms before the eutectoid reaction. Option A is incorrect because it assumes a unique solution. Option B is incorrect because the composition can be determined, just not uniquely. Option D is incorrect because the condition applies to both hypo- and hyper-eutectoid alloys.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 801, "question": "What are the characteristics of various alloy strengthening methods?", "answer": "Grain refinement strengthening, solid solution strengthening, multiphase strengthening, dispersion strengthening (age hardening), and work hardening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释各种合金强化方法的特征，答案提供了详细的文字描述和论述，符合简答题的特点。 | 知识层次: 题目考查对合金强化方法的基本概念和分类的记忆，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个合金强化方法的概念，但正确选项已经明确列出了五种主要的强化方法（晶粒细化强化、固溶强化、多相强化、弥散强化（时效硬化）和加工硬化），考生只需识别和记忆这些基本分类即可。不需要进行复杂的比较分析或深入的概念阐述，因此难度等级为2。", "convertible": true, "correct_option": "Grain refinement strengthening, solid solution strengthening, multiphase strengthening, dispersion strengthening (age hardening), and work hardening", "choice_question": "Which of the following are the characteristics of various alloy strengthening methods?", "conversion_reason": "The answer is a standard list of terms or concepts, which can be converted into a multiple-choice question format by presenting these terms as options and asking the examinee to select the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Grain refinement strengthening, solid solution strengthening, multiphase strengthening, dispersion strengthening (age hardening), and work hardening", "B": "Grain boundary sliding, solid solution softening, precipitation hardening, and strain hardening", "C": "Twin boundary strengthening, vacancy hardening, order hardening, and recrystallization strengthening", "D": "Dislocation pinning, phase transformation hardening, texture strengthening, and annealing softening" }, "correct_answer": "A", "explanation": "The correct answer is A because it comprehensively lists the five fundamental alloy strengthening mechanisms recognized in materials science. Option B mixes valid mechanisms (precipitation hardening, strain hardening) with incorrect concepts (grain boundary sliding is a deformation mechanism, not strengthening; solid solution softening is the opposite effect). Option C combines real but less common mechanisms (twin boundary, order hardening) with incorrect terms (vacancy hardening is negligible; recrystallization actually softens materials). Option D blends correct concepts (dislocation pinning, phase transformation) with inappropriate terms (texture strengthening is situational; annealing causes softening). The distractors exploit common confusions between strengthening/softening mechanisms and deformation/processing effects.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4756, "question": "A three-point bending test was performed on an aluminum oxide specimen having a circular cross section of radius 5.0 mm(0.20 in.); the specimen fractured at a load of 3000N (675 lb f) when the distance between the support points was 40mm (1.6 in.). Another test is to be performed on a specimen of this same material, but one that has a square cross section of 15mm (0.6 in.) length on each edge. At what load would you expect this specimen to fracture if the support point separation is maintained at 40mm (1.6 in.)?", "answer": "the specimen with a square cross section would be expected to fracture at a load of 17,200 n (3870 lb f).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解另一个试样的断裂载荷，答案是一个具体的数值结果，解答过程需要应用材料力学中的三点弯曲测试公式进行计算。 | 知识层次: 题目需要进行多步计算，涉及三点弯曲测试的公式应用和不同截面形状的转换计算，需要综合分析材料的力学行为和几何参数的影响。 | 难度: 在选择题中属于中等难度，需要理解三点弯曲测试的基本原理，掌握圆形和方形截面的惯性矩计算，并能正确应用断裂载荷公式进行多步计算。题目涉及材料力学和几何转换的综合应用，但选择题型提供了正确选项，降低了部分难度。", "convertible": true, "correct_option": "17,200 N (3870 lb f)", "choice_question": "A three-point bending test was performed on an aluminum oxide specimen with a circular cross section of radius 5.0 mm (0.20 in.), which fractured at a load of 3000 N (675 lb f) when the distance between the support points was 40 mm (1.6 in.). Another test is to be performed on a specimen of the same material with a square cross section of 15 mm (0.6 in.) length on each edge. If the support point separation is maintained at 40 mm (1.6 in.), at what load would you expect this specimen to fracture?", "conversion_reason": "The question involves a calculation with a specific numerical answer, making it suitable for conversion to a multiple-choice format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "17,200 N (3870 lb f)", "B": "9,550 N (2150 lb f)", "C": "4,320 N (970 lb f)", "D": "22,500 N (5060 lb f)" }, "correct_answer": "A", "explanation": "正确答案A基于三点弯曲测试中最大弯曲应力公式σ=FL/(πR³)和σ=3FL/(2bd²)的正确转换计算。干扰项B错误地假设了圆形和方形截面的应力集中系数相同。干扰项C错误地使用了弹性模量而非断裂强度进行计算。干扰项D错误地将载荷与截面面积成简单正比关系计算。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 497, "question": "What are the intracrystalline substructures of martensitic transformation products in steel?", "answer": "(3) Intracrystalline substructure: Lath martensite mainly consists of high-density dislocations (1 point); acicular martensite has high-density twins with some dislocations at the edges. (1 point)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释马氏体转变产物的晶内亚结构，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查马氏体转变产物的晶内亚结构的基本概念和分类，主要涉及记忆和理解高密度位错和孪晶等基本特征，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确区分和描述两种不同类型的马氏体（板条马氏体和针状马氏体）的亚结构特征。这要求考生不仅记住定义，还需要理解并能够描述这些亚结构的具体组成（如高密度位错和孪晶）。因此，该题目在选择题型中属于概念解释和描述的难度等级。", "convertible": true, "correct_option": "Lath martensite mainly consists of high-density dislocations; acicular martensite has high-density twins with some dislocations at the edges.", "choice_question": "Which of the following correctly describes the intracrystalline substructures of martensitic transformation products in steel?", "conversion_reason": "The answer is a standard description of the intracrystalline substructures, which can be converted into a multiple-choice question format by presenting it as the correct option among others.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Lath martensite mainly consists of high-density dislocations; acicular martensite has high-density twins with some dislocations at the edges", "B": "Both lath and acicular martensite contain equal proportions of dislocations and twins throughout their substructures", "C": "Acicular martensite is dominated by stacking faults while lath martensite contains primarily deformation twins", "D": "The substructures are identical in both types, consisting of alternating layers of dislocations and twins" }, "correct_answer": "A", "explanation": "The correct answer A precisely describes the distinct substructures: lath martensite's dislocation-dominated structure versus acicular martensite's twin-dominated structure with edge dislocations. Option B exploits the cognitive bias of assuming symmetry between similar materials. Option C uses a professional intuition trap by substituting stacking faults (common in FCC metals) which don't occur in martensite. Option D creates a multi-level verification trap by suggesting identical structures while both types do contain dislocations and twins, just in different configurations.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1455, "question": "For a mixed dislocation line, what is the relationship between the direction of its slip motion and the dislocation line?", "answer": "Perpendicular", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释混合位错线的滑移方向与位错线之间的关系，需要文字解释和论述，而不是从选项中选择或简单判断对错。 | 知识层次: 题目考查对混合位错线滑移方向与位错线方向关系的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目仅考察对混合位错线滑移方向与位错线关系的基本定义记忆，属于最基础的概念性知识，无需解释或复杂分析。", "convertible": true, "correct_option": "Perpendicular", "choice_question": "For a mixed dislocation line, what is the relationship between the direction of its slip motion and the dislocation line?", "conversion_reason": "The answer is a standard term (Perpendicular), which can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Parallel to both Burgers vector and dislocation line", "B": "Perpendicular to the dislocation line", "C": "At 45° to both edge and screw components", "D": "Coincides with the direction of maximum resolved shear stress" }, "correct_answer": "B", "explanation": "The correct answer is B because for mixed dislocations, slip occurs perpendicular to the dislocation line direction. Option A is a trap for those confusing pure screw dislocations (where motion is parallel) with mixed dislocations. Option C exploits the 45° angle between edge/screw components but misapplies it to slip direction. Option D uses a correct materials concept (resolved shear stress) but in the wrong context, as it describes driving force direction rather than actual slip motion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1718, "question": "What is the effect of dislocations on the nucleation of the second phase?", "answer": "Dislocations are preferential sites for the nucleation of the second phase, and typically the second phase can nucleate and grow preferentially at dislocations.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释位错对第二相形核的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及位错对第二相形核的影响机制，需要理解位错作为形核位点的原理，并能够解释第二相在位错处优先形核和生长的原因。这需要对位错和第二相形核的相互作用进行综合分析，属于机理层面的解释，思维深度较高。 | 难度: 在选择题型中，该题目属于较高难度等级。题目要求考生不仅理解位错的基本概念，还需要掌握位错对第二相形核的影响机制。正确选项涉及位错作为第二相形核的择优位置，并解释了第二相在位错处优先形核和生长的机理。这需要考生具备综合运用知识、推理分析和机理解释的能力，属于复杂分析层次。因此，在选择题型内，该题目属于等级4的难度。", "convertible": true, "correct_option": "Dislocations are preferential sites for the nucleation of the second phase, and typically the second phase can nucleate and grow preferentially at dislocations.", "choice_question": "What is the effect of dislocations on the nucleation of the second phase?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dislocations act as preferential nucleation sites by providing strain energy relief and atomic-scale irregularities for heterogeneous nucleation", "B": "Dislocations inhibit second phase nucleation by creating local compressive stress fields that raise the activation energy barrier", "C": "Dislocations have no significant effect on nucleation as their strain fields are negligible compared to thermal fluctuations at typical processing temperatures", "D": "Dislocations only affect nucleation in ionic crystals where their charged nature creates electrostatic interactions with precipitates" }, "correct_answer": "A", "explanation": "Correct answer A describes the well-established role of dislocations in reducing nucleation energy barriers through strain relief and providing structural irregularities. Option B exploits a common misconception about compressive stress fields, which actually assist nucleation by compensating for volume changes. Option C targets the thermal fluctuation fallacy, ignoring that dislocation strain fields persist even at high temperatures. Option D creates a false specialization by suggesting this phenomenon only applies to ionic crystals, when it's actually universal across material systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4728, "question": "Determine the ASTM grain size number if 25 grains per square inch are measured at a magnification of 75 ×.", "answer": "the astm grain size number is 4.8.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定ASTM晶粒度数值，答案是一个具体的数值结果（4.8），这表明解答过程涉及计算步骤。 | 知识层次: 题目需要应用ASTM晶粒度计算公式进行简单计算，属于基本公式的直接套用，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，需要基本公式应用和简单计算。虽然需要套用ASTM grain size number的计算公式，但步骤较为直接，仅涉及单一公式的代入和简单数学运算，无需多个公式组合或复杂分析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "4.8", "choice_question": "Determine the ASTM grain size number if 25 grains per square inch are measured at a magnification of 75 ×.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "4.8", "B": "5.2", "C": "3.6", "D": "6.0" }, "correct_answer": "A", "explanation": "The correct answer is A (4.8) as calculated using the ASTM grain size formula: G = [6.6439 * log10(N*(M^2))] - 3.288, where N=25 grains/in² and M=75. Option B (5.2) exploits the cognitive bias of overestimating the logarithmic relationship. Option C (3.6) is designed to trap those who forget to square the magnification factor. Option D (6.0) preys on the intuition that higher magnification should directly correlate with higher grain size numbers.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 334, "question": "What is the main difference between recrystallization and crystallization?", "answer": "Recrystallization is only a microstructural change without structural transformation, driven by deformation stored energy; crystallization is the process of forming crystals from amorphous liquid, gas, or solid states.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释两个概念之间的主要区别，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对recrystallization和crystallization这两个基本概念的定义和区别的记忆和理解，不涉及复杂的应用或分析。 | 难度: 在选择题中属于中等难度，题目要求区分两个相关但不同的概念（再结晶和结晶），需要理解各自的基本定义和驱动机制。虽然不涉及复杂的概念体系阐述，但需要准确记忆和比较两个过程的本质区别，属于概念解释和描述的层次。", "convertible": true, "correct_option": "Recrystallization is only a microstructural change without structural transformation, driven by deformation stored energy; crystallization is the process of forming crystals from amorphous liquid, gas, or solid states.", "choice_question": "What is the main difference between recrystallization and crystallization?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recrystallization requires pre-existing crystal defects while crystallization can occur in defect-free systems", "B": "Crystallization always occurs below melting temperature while recrystallization requires superheating", "C": "Recrystallization changes crystal symmetry but crystallization preserves atomic arrangement", "D": "Crystallization is exothermic while recrystallization is endothermic" }, "correct_answer": "A", "explanation": "Correct answer A highlights the fundamental difference that recrystallization relies on stored deformation energy from defects, while crystallization is a phase transformation process. Distractors: B exploits temperature intuition but incorrectly assigns superheating requirement; C reverses the actual symmetry behavior; D misleads by suggesting thermodynamic differences that don't fundamentally distinguish the processes.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1313, "question": "Dynamic recovery and dynamic recrystallization refer to the simultaneous occurrence of (15) during deformation.", "answer": "(15) softening and strain hardening.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写一个特定的术语或短语来完成句子，而不是从多个选项中选择或进行判断。答案需要简要的文字描述，符合简答题的特征。 | 知识层次: 题目考查动态回复和动态再结晶的基本概念，属于定义和基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆，但需要考生同时理解动态恢复和动态再结晶的定义，并能够将这两个概念与软化及应变硬化联系起来。这比单纯记忆单个定义（等级1）要求更高，但尚未达到需要阐述复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "softening and strain hardening", "choice_question": "Dynamic recovery and dynamic recrystallization refer to the simultaneous occurrence of which of the following during deformation?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion into a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "softening and strain hardening", "B": "dislocation generation and annihilation", "C": "grain growth and texture development", "D": "phase transformation and twinning" }, "correct_answer": "A", "explanation": "Dynamic recovery and recrystallization involve the competition between strain hardening (dislocation accumulation) and softening (dislocation annihilation/rearrangement). Option B is a partial truth but misses the key softening aspect. Option C describes post-deformation phenomena. Option D involves fundamentally different mechanisms. The subtle balance between simultaneous hardening/softening makes this challenging even for advanced AI models.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1218, "question": "Why is carburization performed in γ-Fe around 930‰, where the diffusion coefficient increases with temperature at high temperatures?", "answer": "At high temperatures, the diffusion coefficient increases with temperature, so high temperatures are chosen. However, excessively high temperatures can cause significant grain growth in austenite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释为什么在特定温度下进行渗碳处理，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目涉及扩散系数与温度关系的机理解释，以及晶粒生长的综合分析，需要结合多个知识点进行推理和分析，思维深度较高。 | 难度: 在选择题型内，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "At high temperatures, the diffusion coefficient increases with temperature, so high temperatures are chosen. However, excessively high temperatures can cause significant grain growth in austenite.", "choice_question": "Why is carburization performed in γ-Fe around 930‰, where the diffusion coefficient increases with temperature at high temperatures?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To maximize carbon solubility while avoiding excessive grain growth in austenite", "B": "Because the diffusion coefficient reaches its maximum value at this temperature", "C": "To prevent the formation of cementite which would block carbon diffusion", "D": "Because γ-Fe transforms to δ-Fe above this temperature, reducing carbon solubility" }, "correct_answer": "A", "explanation": "Correct answer A balances the need for high diffusion rates with microstructural control. Option B is a cognitive bias trap - while diffusion increases with temperature, it doesn't peak at 930°C. Option C exploits a common misconception about cementite formation kinetics. Option D uses a factual error about phase transformation temperatures (δ-Fe forms above 1394°C).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1293, "question": "What does secondary recrystallization conceptually refer to?", "answer": "Secondary recrystallization refers to the phenomenon where, after recrystallization annealing, a metal subjected to higher temperatures or prolonged holding times experiences a few grains rapidly consuming other grains and growing, resulting in the entire metal being composed of a small number of exceptionally large grains that are tens to hundreds of times larger than the post-recrystallization grains.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"secondary recrystallization\"这一概念进行解释和论述，答案是一段详细的文字说明，符合简答题的特征。 | 知识层次: 题目考查对二次再结晶这一基础概念的定义和现象描述，属于记忆和理解层次的知识点，不涉及复杂应用或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生对二次再结晶的定义和现象有较为深入的理解，能够描述其过程和结果。相比于简单的定义简答（等级1），该题目要求考生能够解释和描述一个具体的材料科学现象，属于概念解释和描述的层次（等级2）。", "convertible": true, "correct_option": "Secondary recrystallization refers to the phenomenon where, after recrystallization annealing, a metal subjected to higher temperatures or prolonged holding times experiences a few grains rapidly consuming other grains and growing, resulting in the entire metal being composed of a small number of exceptionally large grains that are tens to hundreds of times larger than the post-recrystallization grains.", "choice_question": "Which of the following best describes secondary recrystallization?", "conversion_reason": "The answer is a standard definition or concept, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A process where abnormal grain growth occurs after primary recrystallization, driven by surface energy minimization in thin films", "B": "The formation of new strain-free grains through nucleation and growth after cold working, replacing deformed grains", "C": "A phenomenon where certain crystallographic orientations grow preferentially due to anisotropic grain boundary energies", "D": "The coarsening of precipitates during aging treatment through Ostwald ripening mechanism" }, "correct_answer": "C", "explanation": "Correct answer C captures the essence of secondary recrystallization where specific orientations dominate due to anisotropic boundary energies. Option A is a surface-energy driven process specific to thin films. Option B describes primary recrystallization, a common confusion point. Option D is about precipitate coarsening, unrelated to grain growth. The trap in A exploits thin film knowledge, B uses primary recrystallization confusion, and D diverts to precipitation hardening concepts.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4649, "question": "What type(s) of bonding would be expected for tungsten?", "answer": "For tungsten, the bonding is metallic since it is a metallic element from the periodic table.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释钨的键合类型，需要文字解释和论述，而不是从选项中选择或判断对错，也不涉及数值计算。 | 知识层次: 题目考查对金属元素钨的键合类型的基本概念记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别钨是金属元素并回忆其键合类型为金属键。题目不涉及复杂概念或分析步骤，属于最基础的定义简答级别。", "convertible": true, "correct_option": "metallic", "choice_question": "What type of bonding would be expected for tungsten?", "conversion_reason": "The answer is a standard term (metallic) that can be presented as a single correct option among other plausible bonding types.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metallic", "B": "Covalent with partial ionic character", "C": "Van der Waals with metallic resonance", "D": "Hybrid metallic-covalent with d-orbital overlap" }, "correct_answer": "A", "explanation": "The correct answer is A because tungsten is a classic transition metal exhibiting pure metallic bonding due to its delocalized electrons. Option B exploits the cognitive bias of expecting complex bonding in transition metals, while Option C creates a false but plausible-sounding hybrid concept. Option D is a professional intuition trap, playing on tungsten's d-electron configuration which might suggest covalent character to an AI without proper context.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3937, "question": "Which of these elements would you expect to form an interstitial solid solution with copper? The elements are: C, Pd, Pt, H, Cr, O, Zn, Ag, Al, Co, Fe, Ni. The criteria for interstitial solid solutions are: these elements have atomic radii that are significantly smaller than the atomic radius of Cu.", "answer": "C, H, and O form interstitial solid solutions. These elements have atomic radii that are significantly smaller than the atomic radius of Cu.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的元素列表中选择符合特定条件（原子半径显著小于铜）的元素，这符合选择题的特征，即从多个选项中选择正确答案。 | 知识层次: 题目考查对间隙固溶体形成条件的记忆和理解，即哪些元素的原子半径显著小于铜的原子半径。这属于基础概念的记忆性知识，不需要复杂的分析或计算。 | 难度: 在选择题型中，该题目需要考生理解间隙固溶体的定义和形成条件，即溶质原子半径必须显著小于溶剂原子半径。虽然题目给出了多个选项，但正确选项（C, H, O）可以通过记忆或简单比较原子半径得出。因此，该题目属于概念理解和简单辨析的难度等级。", "convertible": true, "correct_option": "C, H, and O", "choice_question": "Which of these elements would you expect to form an interstitial solid solution with copper? The criteria for interstitial solid solutions are: these elements have atomic radii that are significantly smaller than the atomic radius of Cu.", "conversion_reason": "The original question is already in a multiple-choice format, and the answer is a specific subset of the given elements. It can be converted to a single-choice question by selecting the correct combination of elements as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "C, H, and O", "B": "H, O, and N", "C": "C, N, and B", "D": "N, B, and Be" }, "correct_answer": "A", "explanation": "The correct answer is A because C, H, and O have atomic radii significantly smaller than Cu (C: 0.77 Å, H: 0.53 Å, O: 0.73 Å vs Cu: 1.28 Å), meeting the criteria for interstitial solid solutions. Option B includes N which is borderline (0.75 Å) and might confuse models relying on periodic trends. Option C uses B (0.87 Å) which is too large, exploiting confusion about borderline cases. Option D includes Be (1.13 Å) which is close to Cu's radius, targeting models that may not precisely compare atomic sizes. The question exploits AI's potential difficulty in precisely evaluating atomic radii thresholds and distinguishing between clearly interstitial vs. borderline elements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3900, "question": "Materials whose constituent particles are bound by which type of bond are generally expected to have the lowest melting temperatures?(a) Covalent(b) Metallic(c) Ionic(d) Van der Waals(e) Hydrogen", "answer": "(d) Van der Waals", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且答案形式为选项中的一个 | 知识层次: 题目考查对不同类型化学键及其性质的基本概念的记忆和理解，特别是范德华力与其他化学键在熔点方面的差异。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需识别不同化学键类型及其一般性质（如熔点）。Van der Waals键是最弱的分子间作用力，其熔点最低是直接记忆性知识，无需复杂分析或概念辨析。", "convertible": true, "correct_option": "Van der Waals", "choice_question": "Materials whose constituent particles are bound by which type of bond are generally expected to have the lowest melting temperatures?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Covalent", "B": "Metallic", "C": "Ionic", "D": "Van der Waals" }, "correct_answer": "D", "explanation": "Van der Waals bonds are the weakest type of intermolecular forces, resulting in the lowest melting temperatures. Covalent (A) and ionic (C) bonds are much stronger, typically leading to high melting points. Metallic bonds (B) also generally result in higher melting temperatures due to the sea of delocalized electrons. The difficulty lies in the fact that AI models might overgeneralize from common examples like diamond (covalent) or metals, failing to recognize the subtle but critical distinction in bond strength hierarchy.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 3, "correct_answers": 3, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2924, "question": "In polyethylene polymer materials, the C一H chemical bond belongs to (A) metallic bond (B) ionic bond (C) covalent bond (D) hydrogen bond", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从选项（A、B、C、D）中选择正确答案，符合选择题的特征 | 知识层次: 题目考查对聚乙烯材料中C一H化学键类型的基本概念记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需识别C一H化学键的类型为共价键，无需复杂辨析或深度理解，属于简单概念识别。", "convertible": true, "correct_option": "covalent bond", "choice_question": "In polyethylene polymer materials, the C一H chemical bond belongs to", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The bond length is shorter than in diamond due to sp2 hybridization", "B": "The bond energy is higher than C一C bonds due to hydrogen's electronegativity", "C": "The bond exhibits partial ionic character (15%) according to Pauling's scale", "D": "The bond angle deviates from 109.5° due to polymer chain constraints" }, "correct_answer": "B", "explanation": "The correct answer is B because C一H bonds in polyethylene are purely covalent and indeed have higher bond energy (413 kJ/mol) than C一C bonds (348 kJ/mol) due to hydrogen's higher electronegativity difference. Option A is misleading by suggesting sp2 hybridization (polyethylene uses sp3). Option C exploits the common misconception about Pauling's scale applying to all bonds. Option D creates confusion by mixing bond angle concepts from different contexts.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1636, "question": "If 6kg of austenite with a carbon content of w_c=0.45% is slowly cooled below 727%, what is the proeutectoid phase?", "answer": "If 6kg of austenite with a carbon content of w_c=0.45% is slowly cooled below 727%, the proeutectoid phase is proeutectoid ferrite.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释在特定条件下（缓慢冷却至727℃以下）的相变产物，答案需要文字描述（proeutectoid ferrite），属于概念性简答而非计算/选择/判断。 | 知识层次: 题目考查对铁碳相图中奥氏体冷却过程中析出相的基础概念记忆，仅需知道0.45%碳含量低于共析点(0.77%)时会析出先共析铁素体这一基本原理，无需复杂分析或计算。 | 难度: 在选择题型中，该题目仅考察对基础概念的记忆，即碳含量为0.45%的奥氏体在缓慢冷却至727℃以下时形成的先共析相是什么。不需要复杂的分析或推理，只需记住基本的铁碳相图知识即可作答。", "convertible": true, "correct_option": "proeutectoid ferrite", "choice_question": "If 6kg of austenite with a carbon content of w_c=0.45% is slowly cooled below 727%, what is the proeutectoid phase?", "conversion_reason": "The answer is a standard term in metallurgy, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "proeutectoid ferrite", "B": "proeutectoid cementite", "C": "pearlite", "D": "ledeburite" }, "correct_answer": "A", "explanation": "The correct answer is proeutectoid ferrite because at 0.45% carbon content (hypoeutectoid composition), the first phase to form upon slow cooling below 727°C is ferrite. Option B is a cognitive bias trap - cementite forms in hypereutectoid steels. Option C exploits the common pearlite misconception - pearlite forms at the eutectoid reaction, not before. Option D is a professional intuition trap - ledeburite forms in cast irons, not steels.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1757, "question": "In the thermodynamic relation of diffusion coefficient, $\\\\left(1+\\\\frac{\\\\partial\\\\mathrm{ln}\\\\gamma_{i}}{\\\\partial\\\\mathrm{ln}N_{\\\\mathrm{i}}}\\\\right)$ is called the thermodynamic factor of diffusion coefficient. In a non-ideal mixing system: when the thermodynamic factor of diffusion coefficient > 0, the diffusion result causes the solute to ____; when the thermodynamic factor of diffusion coefficient < 0, the diffusion result causes the solute to ____. a. segregate b. concentration remains unchanged c. concentration tends to be uniform", "answer": "c a", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从给定的选项（a. segregate b. concentration remains unchanged c. concentration tends to be uniform）中选择正确的填空答案，符合选择题的特征。 | 知识层次: 题目涉及非理想混合系统中扩散系数的热力学因子及其对溶质扩散结果的影响，需要理解热力学因子的概念及其与扩散行为的关系，属于中等应用层次。需要将热力学因子与扩散结果联系起来进行分析，但不需要复杂的推理或综合运用。 | 难度: 在选择题型中，该题目属于复杂分析过程的判断难度等级。题目要求考生不仅要理解扩散系数的热力学因子概念，还需要掌握非理想混合系统中热力学因子与扩散结果之间的关联。解题步骤涉及对热力学因子正负值的含义进行判断，并将其与溶质的扩散行为（偏聚或均匀化）联系起来。这种综合分析过程超出了简单概念记忆或单一知识点应用的范围，属于需要多步推理和概念关联的中等应用层次题目。", "convertible": true, "correct_option": "c a", "choice_question": "In the thermodynamic relation of diffusion coefficient, $\\left(1+\\frac{\\partial\\mathrm{ln}\\gamma_{i}}{\\partial\\mathrm{ln}N_{\\mathrm{i}}}\\right)$ is called the thermodynamic factor of diffusion coefficient. In a non-ideal mixing system: when the thermodynamic factor of diffusion coefficient > 0, the diffusion result causes the solute to ____; when the thermodynamic factor of diffusion coefficient < 0, the diffusion result causes the solute to ____.", "conversion_reason": "The original question is already in a multiple-choice format, and the answer is provided as a combination of options. It can be converted to a single-choice question by keeping the question as is and using the provided answer as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "c a", "B": "选项C", "C": "选项B", "D": "选项D" }, "correct_answer": "A", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 1081, "question": "Write all the crystal planes included in the {111} crystal plane family in the cubic crystal system.", "answer": "(111), (1̄11), (11̄1), (111̄).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求写出立方晶系中{111}晶面族包含的所有晶面，答案需要列举具体的晶面指数，属于需要文字解释和列举的简答题类型。 | 知识层次: 题目考查对立方晶系中{111}晶面族包含的所有晶面的记忆和理解，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需要回忆立方晶系中{111}晶面族包含的具体晶面。正确选项直接给出了所有可能的晶面组合，无需额外计算或推理步骤。因此，在选择题型内属于最简单的难度等级。", "convertible": true, "correct_option": "(111), (1̄11), (11̄1), (111̄)", "choice_question": "下列哪些晶面属于立方晶系中的{111}晶面族？", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(111), (1̄11), (11̄1), (111̄)", "B": "(111), (1̄1̄1), (11̄1̄), (1̄11̄)", "C": "(111), (110), (101), (011)", "D": "(111), (1̄11), (11̄1), (111̄), (1̄1̄1̄)" }, "correct_answer": "A", "explanation": "正确答案A包含了立方晶系{111}晶面族的全部四个等效晶面。干扰项B错误地包含了(1̄1̄1)等非等效晶面，利用了负指数对称性的认知偏差。干扰项C混入了{110}晶面族的常见晶面，制造了晶面族分类的直觉陷阱。干扰项D额外包含了(1̄1̄1̄)晶面，该晶面实际上与(111)是平行关系而非等效关系，设置了多层次验证陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3700, "question": "A 0.02% C steel is to be carburized at 1200^{\\circ} C in 4h, with a point 0.6mm beneath the surface reaching 0.45% C. Calculate the carbon content required at the surface of the steel.", "answer": "the carbon content required at the surface of the steel is 0.53% C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，以确定钢表面的碳含量。答案是一个具体的数值结果（0.53% C），这符合计算题的特征。 | 知识层次: 题目需要进行多步计算，涉及碳扩散公式的应用和边界条件的设定，需要理解碳浓度分布的概念，并能够将实际问题转化为数学模型进行计算。虽然不涉及复杂的机理分析或创新设计，但需要一定的综合分析能力和概念关联。 | 难度: 在选择题中属于中等偏上难度，需要综合运用扩散定律和边界条件进行计算。题目涉及多步骤计算过程（包括扩散系数计算、误差函数应用等），并要求将多个材料科学概念（如碳浓度梯度、稳态扩散条件）关联起来进行综合分析。虽然选择题型提供了正确选项降低了部分难度，但仍需较强的概念理解和计算能力才能正确解答。", "convertible": true, "correct_option": "0.53% C", "choice_question": "A 0.02% C steel is to be carburized at 1200°C in 4h, with a point 0.6mm beneath the surface reaching 0.45% C. The carbon content required at the surface of the steel is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.53% C", "B": "0.48% C", "C": "0.60% C", "D": "0.40% C" }, "correct_answer": "A", "explanation": "正确答案A是通过Fick第二定律精确计算得出的表面碳浓度。干扰项B利用了常见的线性近似误差，忽略了实际浓度梯度的非线性特性。干扰项C利用了高温下扩散系数快速增加的直觉，但错误地放大了时间因素的影响。干扰项D则基于表面浓度应接近目标浓度的错误直觉，忽略了扩散过程的边界条件要求。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2221, "question": "A low-carbon steel part has developed banded structure, how to eliminate or improve the banded structure through heat treatment methods?", "answer": "For materials that have developed banded structure, heating in the single-phase region and normalizing treatment can eliminate or improve it.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求通过文字解释和论述来回答如何通过热处理方法消除或改善带状组织，答案提供了具体的处理方法和解释，符合简答题的特征。 | 知识层次: 题目要求对带状组织的消除或改善提出热处理方案，需要理解带状组织的形成原因以及不同热处理工艺（如单相区加热和正火处理）对其影响。这涉及多个概念的关联和综合分析，但不需要复杂的机理解释或创新设计。 | 难度: 在选择题中属于中等难度，需要理解低碳钢带状组织的形成机制以及热处理工艺（如单相区加热和正火处理）对其影响。题目要求考生将材料科学基础知识和热处理工艺相结合，进行综合分析，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "Heating in the single-phase region and normalizing treatment", "choice_question": "How can the banded structure in a low-carbon steel part be eliminated or improved through heat treatment methods?", "conversion_reason": "The answer is a standard heat treatment method, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Heating in the single-phase region and normalizing treatment", "B": "Rapid quenching to form martensite followed by tempering", "C": "Prolonged annealing below the eutectoid temperature", "D": "Cyclic heat treatment between A1 and A3 temperatures" }, "correct_answer": "A", "explanation": "The correct answer is A because heating in the single-phase region (austenite) followed by normalizing helps homogenize the microstructure and eliminate banding. B is incorrect as martensite formation would preserve the banded structure. C is wrong because sub-eutectoid annealing cannot eliminate the compositional banding. D is a distractor using a plausible-sounding but ineffective method for this purpose.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2990, "question": "In polymer materials, what is the atomic bonding between molecules (primary valence force)?", "answer": "Covalent bond", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答一个具体的概念（原子键合类型），答案是一个术语（Covalent bond），不需要选择、判断或计算，符合简答题的特征。 | 知识层次: 题目考查聚合物材料中分子间原子键合的基本概念记忆，属于基础概念层次 | 难度: 在选择题型中，该题目仅考察对聚合物材料中分子间原子键合类型（共价键）的基础定义记忆，属于最基本的概念性知识，无需解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Covalent bond", "choice_question": "In polymer materials, what is the atomic bonding between molecules (primary valence force)?", "conversion_reason": "The answer is a standard term (Covalent bond), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Covalent bond", "B": "Hydrogen bond", "C": "Van der Waals force", "D": "Ionic bond" }, "correct_answer": "A", "explanation": "The correct answer is A because in polymer materials, the primary valence force between molecules is the covalent bond, which forms the polymer backbone. Option B is a strong cognitive bias trap as hydrogen bonds are important in secondary interactions but not primary bonds. Option C exploits the common misconception about intermolecular forces in polymers. Option D is a professional intuition trap since ionic bonds do exist in some materials but are not the primary valence force in typical polymers.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 350, "question": "(Taking the face-centered cubic unit cell as an example) What are the common parameters used to describe the characteristics of a crystal structure (unit cell)? What is the stacking sequence of an FCC unit cell?", "answer": "The stacking sequence is ABCABC.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求文字解释和论述晶体结构（晶胞）的常见参数以及面心立方晶胞的堆垛顺序，答案以文字形式给出，没有涉及计算或选择。 | 知识层次: 题目考查晶体结构的基本参数和面心立方(FCC)晶体的堆垛顺序，这些都是材料科学中基础概念的记忆和理解，不涉及复杂的计算或分析。 | 难度: 在选择题型中，该题目仅要求记忆并选择FCC晶体的堆垛顺序（ABCABC），属于基础概念记忆层次。题目不涉及复杂的概念解释或分析，仅需直接回忆定义性知识，因此难度等级为1。", "convertible": true, "correct_option": "ABCABC", "choice_question": "What is the stacking sequence of an FCC unit cell?", "conversion_reason": "The answer to the question is a standard term (stacking sequence) which can be presented as a single correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "ABCABC", "B": "ABABAB", "C": "ABACAB", "D": "AABBCC" }, "correct_answer": "A", "explanation": "The correct stacking sequence for FCC is ABCABC, representing the repeating pattern of atomic layers. Option B (ABABAB) is the HCP stacking sequence, exploiting confusion between two common close-packed structures. Option C (ABACAB) mimics the correct pattern but introduces an irregularity that seems plausible at first glance. Option D (AABBCC) creates a false symmetry that appeals to intuitive pattern recognition but doesn't correspond to any real crystal structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 706, "question": "Polymorphism", "answer": "Substances with the same chemical composition can form crystals with different structures under different thermodynamic conditions", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对\"Polymorphism\"进行解释说明，答案是以文字形式给出的概念性描述，符合简答题的特征 | 知识层次: 题目考查对多晶型（Polymorphism）这一基础概念的记忆和理解，要求解释不同热力学条件下相同化学组成的物质可以形成不同晶体结构的现象。这属于材料科学中的基本原理和定义性知识，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等偏下难度。题目考察的是对\"多晶型\"这一基础概念的理解和描述，需要考生能够准确识别并解释不同热力学条件下相同化学成分物质可以形成不同晶体结构的现象。虽然涉及一定的概念理解，但不需要复杂的分析或比较，属于概念解释和描述层次的难度。", "convertible": true, "correct_option": "Substances with the same chemical composition can form crystals with different structures under different thermodynamic conditions", "choice_question": "Which of the following best describes polymorphism?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Substances with the same chemical composition can form crystals with different structures under different thermodynamic conditions", "B": "Materials exhibiting different mechanical properties when loaded along different crystallographic directions", "C": "The ability of a material to exist in both crystalline and amorphous states depending on processing conditions", "D": "Phase transformations that occur at constant chemical composition but varying temperature and pressure" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines polymorphism as the phenomenon where the same chemical substance can crystallize into different structures under varying thermodynamic conditions. Option B describes anisotropy, not polymorphism. Option C confuses polymorphism with the crystalline/amorphous duality, which is a different concept. Option D describes phase transformations in general, not specifically polymorphism which requires different crystal structures of the same composition.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3890, "question": "The nucleus of an atom contains protons?", "answer": "Yes, the nucleus of an atom contains protons.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（\"The nucleus of an atom contains protons\"），答案直接给出了判断结果（\"Yes\"），符合判断题的特征。 | 知识层次: 题目考查原子核基本组成的记忆性知识，仅需基础概念认知能力 | 难度: 在选择题型中，该题目仅涉及基础概念的正误判断，即原子核是否包含质子这一基本事实。题目不需要任何复杂推理或概念间的比较分析，仅需记忆性知识即可正确回答。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Yes, the nucleus of an atom contains protons.", "choice_question": "The nucleus of an atom contains protons?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit perfect ionic bonding with no covalent character.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics have predominantly ionic bonding, most exhibit some degree of covalent character. The statement uses 'all' and 'perfect' which are absolute terms that don't account for the complex bonding nature in ceramics like silicon carbide (SiC) which has significant covalent bonding.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4200, "question": "What type(s) of bonding would be expected for rubber?", "answer": "For rubber, the bonding is covalent with some van der Waals. (Rubber is composed primarily of carbon and hydrogen atoms.)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释橡胶的键合类型，答案提供了详细的文字解释和论述，而不是从选项中选择或简单的对错判断。 | 知识层次: 题目考查对橡胶材料中化学键类型的基本概念记忆和理解，属于基础知识的直接应用，不需要复杂的分析或综合。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目考察的是基础概念记忆（橡胶的键合类型），但需要学生同时掌握共价键和范德华力两种键合方式的概念，并能将其正确组合应用于特定材料。这比单纯记忆单一键合类型（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。", "convertible": true, "correct_option": "covalent with some van der Waals", "choice_question": "What type(s) of bonding would be expected for rubber?", "conversion_reason": "The answer is a standard term describing the bonding in rubber, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "covalent with some van der Waals", "B": "ionic with hydrogen bonding", "C": "metallic with covalent", "D": "pure van der Waals" }, "correct_answer": "A", "explanation": "Rubber primarily consists of long polymer chains with covalent bonds within the chains and weaker van der Waals forces between chains. Option B exploits the common confusion between polymer structures and biological materials. Option C targets the misconception that elasticity implies metallic bonding. Option D is a half-truth that ignores the essential covalent backbone structure.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4699, "question": "Under conditions where cupric oxide (CuO) is exposed to reducing atmospheres at elevated temperatures, some of the Cu2+ ions will become Cu+. How would you express the chemical formula for this nonstoichiometric material?", "answer": "The chemical formula for this nonstoichiometric material is Cu1+ O or CuO1-x, where x is some small fraction.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求用文字解释和论述非化学计量材料的化学式表达方式，答案需要提供具体的化学式并解释变量含义，属于需要文字表述的简答题类型。 | 知识层次: 题目要求理解非化学计量材料的化学式表达，需要将氧化还原反应的概念与材料化学式表达相结合，属于中等应用层次。虽然不涉及复杂计算，但需要对材料在特定条件下的变化有较深入的理解，并能正确表达非化学计量比。 | 难度: 在选择题中属于较高难度，需要理解非化学计量比材料的概念，并能够将Cu2+还原为Cu+的化学变化与化学式表达联系起来。此外，题目要求考生能够正确表达非化学计量比材料的化学式，这需要一定的综合分析能力和对化学概念的理解深度。", "convertible": true, "correct_option": "Cu1+ O or CuO1-x, where x is some small fraction", "choice_question": "Under conditions where cupric oxide (CuO) is exposed to reducing atmospheres at elevated temperatures, some of the Cu2+ ions will become Cu+. Which of the following correctly expresses the chemical formula for this nonstoichiometric material?", "conversion_reason": "The answer is a standard chemical formula, which can be presented as a correct option among others in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "CuO0.8", "B": "Cu2O", "C": "CuO with oxygen vacancies", "D": "Cu1.2O" }, "correct_answer": "A", "explanation": "The correct answer is A because nonstoichiometric CuO under reducing conditions loses some oxygen, leading to a formula CuO1-x where x is a small fraction (here represented as 0.8). B is incorrect as it represents stoichiometric cuprous oxide, not nonstoichiometric CuO. C is a partially correct description but not a valid chemical formula. D is incorrect as it suggests excess copper rather than oxygen deficiency.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3715, "question": "A force of 20,000 N will cause a 1 cm × 1 cm bar of magnesium to stretch from 10 cm to 10.045 cm. Calculate the modulus of elasticity in psi.", "answer": "the modulus of elasticity is 6.44 × 10^6 psi.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解镁棒的弹性模量，答案是一个具体的数值结果。 | 知识层次: 题目需要应用基本的弹性模量计算公式，进行简单的数值计算和单位转换，属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要理解弹性模量的概念并应用公式E = (F/A)/(ΔL/L)，但计算步骤相对直接，且题目提供了所有必要的数据。不需要多个公式组合或复杂的转换，因此难度等级为2。", "convertible": true, "correct_option": "6.44 × 10^6 psi", "choice_question": "A force of 20,000 N will cause a 1 cm × 1 cm bar of magnesium to stretch from 10 cm to 10.045 cm. The modulus of elasticity is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.44 × 10^6 psi", "B": "44.4 GPa", "C": "3.22 × 10^6 psi (shear modulus)", "D": "6.44 × 10^4 MPa" }, "correct_answer": "A", "explanation": "正确答案A是通过应力(20,000N/0.0001m²=200MPa)除以应变(0.045cm/10cm=0.0045)得到弹性模量44.4GPa，再转换为psi的正确结果。干扰项B是SI单位的正确数值但题目要求psi单位；C利用镁合金的剪切模量(约17GPa)进行混淆；D将正确数值错误放大了1000倍并使用了MPa单位，利用单位换算和数量级直觉制造陷阱。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2010, "question": "Analyze the type of solid solution formed by N in α-Fe and γ-Fe, their locations, and the solubility (mole fraction). The atomic radii of the elements are as follows: N: 0.071 nm, α-Fe: 0.124 nm, γ-Fe: 0.126 nm", "answer": "N forms an interstitial solid solution in α-Fe, with a maximum solubility (mole fraction) of about 0.1×10^-2 at 590°C, decreasing to 0.001×10^-2 at room temperature. In α-Fe, N is mostly located at the octahedral interstitial sites. In γ-Fe, N forms an interstitial solid solution, located at the octahedral interstitial sites, with a maximum solubility (mass fraction) of about 2.8×10^-2.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求分析N在α-Fe和γ-Fe中形成的固溶体类型、位置以及溶解度，需要详细的文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求分析N在α-Fe和γ-Fe中形成的固溶体类型、位置以及溶解度，涉及多个概念的综合应用，包括固溶体类型、原子半径比较、溶解度变化等。需要理解并关联多个知识点，进行一定的分析和解释，但不需要复杂的推理或创新设计。 | 难度: 在选择题型中，该题目属于较高难度。题目要求考生不仅理解间隙固溶体的基本概念，还需要掌握N在α-Fe和γ-Fe中的具体位置（八面体间隙）以及在不同温度下的溶解度变化。此外，题目还涉及原子半径的比较和不同晶体结构（α-Fe和γ-Fe）对固溶度的影响，需要考生进行多角度分析和综合判断。这些要求超出了简单的概念记忆，需要较深的理解和应用能力。", "convertible": true, "correct_option": "N forms an interstitial solid solution in α-Fe, with a maximum solubility (mole fraction) of about 0.1×10^-2 at 590°C, decreasing to 0.001×10^-2 at room temperature. In α-Fe, N is mostly located at the octahedral interstitial sites. In γ-Fe, N forms an interstitial solid solution, located at the octahedral interstitial sites, with a maximum solubility (mass fraction) of about 2.8×10^-2.", "choice_question": "Analyze the type of solid solution formed by N in α-Fe and γ-Fe, their locations, and the solubility (mole fraction). The atomic radii of the elements are as follows: N: 0.071 nm, α-Fe: 0.124 nm, γ-Fe: 0.126 nm. Which of the following statements is correct?", "conversion_reason": "The answer is a standard description of the solid solution formed by N in α-Fe and γ-Fe, which can be presented as a correct option in a multiple-choice question format. The question can be rephrased to ask for the correct statement among given options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "N forms an interstitial solid solution in α-Fe, with a maximum solubility (mole fraction) of about 0.1×10^-2 at 590°C, decreasing to 0.001×10^-2 at room temperature. In α-Fe, N is mostly located at the octahedral interstitial sites. In γ-Fe, N forms an interstitial solid solution, located at the octahedral interstitial sites, with a maximum solubility (mass fraction) of about 2.8×10^-2.", "B": "N forms a substitutional solid solution in both α-Fe and γ-Fe due to its small atomic radius, with higher solubility in γ-Fe (mole fraction ~0.05) than in α-Fe (mole fraction ~0.01) at high temperatures.", "C": "N forms an interstitial solid solution in α-Fe but a substitutional solid solution in γ-Fe, with maximum solubilities of 0.5×10^-2 (mole fraction) in α-Fe and 1.2×10^-2 (mole fraction) in γ-Fe at their respective eutectoid temperatures.", "D": "N forms interstitial solid solutions in both α-Fe and γ-Fe, but preferentially occupies tetrahedral sites in α-Fe and octahedral sites in γ-Fe, with nearly equal maximum solubilities of ~1×10^-2 (mole fraction) in both phases." }, "correct_answer": "A", "explanation": "The correct answer is A because: 1) N's small radius (0.071nm) compared to Fe (0.124-0.126nm) makes it form interstitial solutions, 2) α-Fe's BCC structure favors octahedral sites for N, 3) solubility data matches experimental measurements. Option B incorrectly suggests substitutional solution. Option C wrongly claims substitutional solution in γ-Fe. Option D incorrectly states tetrahedral site preference in α-Fe and equal solubilities, while in reality octahedral sites are preferred and solubilities differ significantly between phases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3230, "question": "Describe the similarities between twinning and slip", "answer": "The similarities between slip and twinning are that both are fundamental modes of crystal plastic deformation, both occur as shear under shear stress along certain crystallographic planes and directions, and the crystal structure type remains unchanged before and after deformation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求描述两种晶体塑性变形方式的相似之处，需要文字解释和论述，答案也以文字形式呈现，符合简答题的特征 | 知识层次: 题目考查对晶体塑性变形基本模式（滑移和孪生）的相似性的记忆和理解，属于基础概念的对比和描述，不涉及复杂分析或综合应用。 | 难度: 在选择题中属于中等难度，需要理解并比较两个基本概念（滑移和孪生）的相似之处，涉及对晶体塑性变形基本原理的记忆和描述，但不需要复杂的分析或推理。", "convertible": true, "correct_option": "Both are fundamental modes of crystal plastic deformation, both occur as shear under shear stress along certain crystallographic planes and directions, and the crystal structure type remains unchanged before and after deformation.", "choice_question": "What are the similarities between twinning and slip?", "conversion_reason": "The answer is a standard description of the similarities between twinning and slip, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Both involve shear deformation but twinning preserves crystal orientation while slip changes it", "B": "Both require thermal activation energy and occur preferentially at grain boundaries", "C": "Both produce permanent deformation through dislocation motion along close-packed directions", "D": "Both are reversible processes that maintain the original crystal structure after unloading" }, "correct_answer": "A", "explanation": "Correct answer A captures the key similarity (shear deformation) while highlighting the critical difference in orientation preservation. Option B is wrong because slip doesn't require thermal activation and twinning often occurs within grains. Option C is partially correct but twinning involves coordinated atom movement rather than dislocation motion. Option D is completely wrong as both processes are irreversible. The traps exploit common misconceptions about activation energy requirements (B), deformation mechanisms (C), and reversibility (D).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1431, "question": "The commonly used method to refine grains in casting processes is (19)", "answer": "(19) Increasing the cooling rate", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个简短的具体答案（\"Increasing the cooling rate\"），而不是从多个选项中选择或判断对错，也不需要计算或详细论述。 | 知识层次: 题目考查的是铸造过程中细化晶粒的常用方法，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于基础概念记忆类型，仅需考生回忆并识别铸造过程中细化晶粒的常用方法。题目仅涉及单一知识点（冷却速率与晶粒尺寸的关系），无需复杂分析或概念比较，属于最基础的难度等级。", "convertible": true, "correct_option": "Increasing the cooling rate", "choice_question": "The commonly used method to refine grains in casting processes is:", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increasing the cooling rate", "B": "Decreasing the pouring temperature", "C": "Adding grain refiners (e.g., TiB2)", "D": "Applying ultrasonic vibration during solidification" }, "correct_answer": "A", "explanation": "The correct answer is A because faster cooling rates promote higher nucleation rates, leading to finer grain structures. Option B is a strong distractor as decreasing pouring temperature seems logical but primarily affects superheat rather than grain size. Option C is a classic 'textbook trap' - while grain refiners are effective, they're not the most 'commonly used' method in general casting. Option D exploits cutting-edge research knowledge that's not yet widely adopted in industrial practice.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1591, "question": "The microscopic mechanisms of diffusion in crystalline solids include (14)", "answer": "(14) exchange mechanism", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释扩散的微观机制，需要文字描述而非选择或判断，答案形式为简短的文字回答而非计算 | 知识层次: 题目考查晶体固体中扩散的微观机制，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察对扩散微观机制中最基础的定义性知识（交换机制）的记忆，属于最基础的概念记忆层次。题目仅要求识别正确选项，无需解释或分析，解题步骤极为简单，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "exchange mechanism", "choice_question": "The microscopic mechanisms of diffusion in crystalline solids include:", "conversion_reason": "The answer is a standard term, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Exchange mechanism", "B": "Dislocation climb-controlled diffusion", "C": "Grain boundary sliding", "D": "Nabarro-Herring creep" }, "correct_answer": "A", "explanation": "The exchange mechanism is the fundamental atomic-scale process for diffusion in crystalline solids, involving direct swapping of atoms. Dislocation climb (B) is a macroscopic deformation mechanism, not an atomic diffusion process. Grain boundary sliding (C) is a high-temperature deformation mechanism unrelated to atomic diffusion. Nabarro-Herring creep (D) is a bulk diffusion phenomenon, not a microscopic mechanism. Options B-D exploit common material science concept confusions by presenting real but irrelevant mechanisms that sound plausible for diffusion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4152, "question": "Match the type of light transmission with its description: Transmits light diffusely.", "answer": "A translucent material transmits light diffusely.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求将光的传输类型与其描述进行匹配，属于从多个选项中选择正确答案的类型 | 知识层次: 题目考查对材料光学性质基本概念的记忆和理解，即透明材料和半透明材料在光传输特性上的区别。这属于基础概念记忆层次的知识点。 | 难度: 在选择题型中，该题目仅要求识别并匹配基础概念的定义（translucent material与diffuse light transmission的关系），属于直接记忆性知识，无需复杂理解或辨析步骤。", "convertible": true, "correct_option": "A translucent material transmits light diffusely.", "choice_question": "Which type of material transmits light diffusely?", "conversion_reason": "The original question is a matching question that can be rephrased as a multiple-choice question by asking which material corresponds to the given description of light transmission.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Translucent material", "B": "Transparent material with surface roughness", "C": "Single crystal with lattice defects", "D": "Amorphous metal with nanoscale heterogeneity" }, "correct_answer": "A", "explanation": "Translucent materials by definition transmit light diffusely due to internal scattering centers. Option B exploits the common misconception that surface roughness alone causes diffuse transmission, while in reality it primarily causes diffuse reflection. Option C targets the intuition that lattice defects scatter light, but single crystals still transmit light directionally. Option D uses the technically correct fact that amorphous metals have heterogeneity, but this primarily affects mechanical properties rather than optical transmission.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 458, "question": "What effect does a rough interface have on the crystal growth morphology?", "answer": "For a rough interface, under a positive temperature gradient, planar growth occurs. Under a negative temperature gradient, dendritic growth occurs.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释粗糙界面对晶体生长形态的影响，答案提供了文字解释和论述，符合简答题的特征。 | 知识层次: 题目需要理解粗糙界面对晶体生长形态的影响，并能够根据温度梯度的正负条件分析不同的生长模式（平面生长或枝晶生长）。这涉及多个概念的关联和综合分析，但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解粗糙界面对晶体生长形态的影响，并能够关联正负温度梯度下的不同生长模式（平面生长和枝晶生长）。这涉及多步概念关联和综合分析，但不需要进行多角度或深度关联性分析。", "convertible": true, "correct_option": "For a rough interface, under a positive temperature gradient, planar growth occurs. Under a negative temperature gradient, dendritic growth occurs.", "choice_question": "What effect does a rough interface have on the crystal growth morphology?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Planar growth under positive temperature gradient, dendritic growth under negative gradient", "B": "Dendritic growth regardless of temperature gradient direction", "C": "Spiral growth due to screw dislocations at the interface", "D": "Isotropic spherical growth morphology" }, "correct_answer": "A", "explanation": "The correct answer A reflects the fundamental relationship between interface roughness and growth morphology. Option B exploits the common misconception that roughness always leads to dendritic growth. Option C uses a valid crystal growth mechanism (spiral growth) but in the wrong context (requires specific dislocation types). Option D appeals to the intuitive but incorrect assumption that roughness would cause isotropic growth.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 341, "question": "Briefly describe the effect of deformation amount on metal properties under uniaxial compression?", "answer": "As the deformation amount increases, strength and hardness improve, while plasticity decreases.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述变形量对金属性能的影响，需要用文字解释和论述，答案也是以文字形式给出解释，符合简答题的特征。 | 知识层次: 题目考查金属在单轴压缩下变形量对性能影响的基本概念记忆和理解，属于基础概念层次。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解并描述变形量对金属性能的影响，包括强度、硬度和塑性的变化趋势。这比单纯记忆定义（等级1）要求更高，但不需要复杂的分析或概念体系阐述（等级3）。", "convertible": true, "correct_option": "As the deformation amount increases, strength and hardness improve, while plasticity decreases.", "choice_question": "What is the effect of deformation amount on metal properties under uniaxial compression?", "conversion_reason": "The answer is a standard description that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Yield strength increases while fracture toughness remains constant", "B": "Both hardness and ductility increase proportionally with deformation", "C": "Dislocation density decreases leading to improved electrical conductivity", "D": "Strain hardening occurs but the effect saturates at 5% deformation" }, "correct_answer": "A", "explanation": "Correct answer A reflects the actual relationship where yield strength increases due to strain hardening while fracture toughness (a material property) remains largely unaffected by deformation. Option B exploits the common misconception that ductility would increase with deformation. Option C reverses the actual dislocation dynamics and falsely associates it with conductivity. Option D uses a plausible saturation concept but with an unrealistically low threshold value.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3456, "question": "Why is it still necessary to develop ledeburitic steel?", "answer": "Because it has high hardness, high wear resistance, and red hardness, this steel is developed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么需要开发莱氏体钢，答案需要提供文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释莱氏体钢的发展必要性，涉及对其性能特点（高硬度、高耐磨性、红硬性）的理解和应用，需要将材料性能与实际应用需求关联起来进行综合分析，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解ledeburitic steel的多个性能特点（高硬度、高耐磨性、红硬性）并进行综合分析，但不需要多角度或深度关联性分析。", "convertible": true, "correct_option": "Because it has high hardness, high wear resistance, and red hardness, this steel is developed.", "choice_question": "Why is it still necessary to develop ledeburitic steel?", "conversion_reason": "The answer is a standard explanation that can be directly used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To achieve ultra-high hardness (>65 HRC) while maintaining sufficient toughness for cutting tool applications", "B": "Because its eutectic microstructure provides better corrosion resistance than martensitic steels", "C": "To combine the formability of austenitic steels with the strength of pearlitic steels", "D": "For applications requiring exceptional creep resistance at temperatures above 1000°C" }, "correct_answer": "A", "explanation": "Correct answer A highlights the key properties (hardness and toughness) that make ledeburitic steel valuable for cutting tools. Option B is wrong because corrosion resistance is not a primary characteristic of ledeburitic steel (cognitive bias trap). Option C is incorrect as it confuses ledeburitic steel's properties with other steel types (intuition trap). Option D is misleading by suggesting high-temperature creep resistance, which is not a feature of ledeburitic steels (multi-level verification trap).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 219, "question": "Using Na2CO3 and Na2SiO3 to dilute the same type of clay slurry (mainly composed of kaolinite mineral), compare the differences in thixotropy of the two slurries when the same amount of electrolyte is added.", "answer": "Adding Na2CO3 basically has no effect on the thixotropy of the clay, while adding Na2SiO3 reduces the thixotropy of the slurry.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种电解质对粘土浆体触变性的影响，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求比较两种电解质对黏土浆体触变性的影响，涉及对电解质作用机理的理解和应用，需要综合分析不同电解质与黏土矿物之间的相互作用，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生掌握Na2CO3和Na2SiO3对粘土浆体触变性的影响，并能够区分两者之间的差异。虽然题目提供了正确选项，但考生仍需具备一定的材料科学知识，特别是关于电解质对粘土浆体性质的影响，以及触变性的概念。此外，题目还要求考生能够综合分析不同电解质的作用效果，这增加了题目的复杂性。", "convertible": true, "correct_option": "Adding Na2CO3 basically has no effect on the thixotropy of the clay, while adding Na2SiO3 reduces the thixotropy of the slurry.", "choice_question": "Using Na2CO3 and Na2SiO3 to dilute the same type of clay slurry (mainly composed of kaolinite mineral), compare the differences in thixotropy of the two slurries when the same amount of electrolyte is added.", "conversion_reason": "The answer is a standard statement that can be directly used as a correct option in a multiple-choice question. The question can be reformulated to fit a multiple-choice format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Adding Na2CO3 increases thixotropy while Na2SiO3 decreases it due to different ion hydration effects", "B": "Both electrolytes reduce thixotropy equally by breaking clay particle networks", "C": "Na2CO3 has no effect on thixotropy while Na2SiO3 reduces it due to silicate ion adsorption", "D": "Both electrolytes increase thixotropy by promoting edge-to-face particle interactions" }, "correct_answer": "C", "explanation": "Correct answer is C because Na2CO3 dissociates into Na+ and CO3^2- ions that don't significantly affect kaolinite's surface charge, while Na2SiO3's silicate ions adsorb on clay surfaces reducing particle interactions. Option A is a hydration effect misconception. Option B is wrong because it ignores Na2CO3's ineffectiveness. Option D reverses the actual effects by suggesting incorrect particle interaction mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2320, "question": "Nickel is alloyed with Th having ${\\\\boldsymbol{w}}_{\\\\mathrm{Th}}$ of 0.01 to form an alloy, which is then made into powder, pressed into the desired shape, and sintered into the final product, during which Th is completely oxidized. Calculate the volume fraction of $\\\\mathrm{ThO}_{2}$ produced in this Th-Ni material. Given the density of $\\\\mathrm{ThO}_{2}$ is $9.86~\\\\mathrm{g/cm^{3}}$, Ni is $8.98~\\\\mathrm{g/cm}^{3}$, and Th is $11.72~\\\\mathrm{g/cm}^{3}$.", "answer": "The volume fraction of $\\\\mathrm{ThO}_{2}$ is $0.0084 (0.84\\\\%)$.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，以确定体积分数，且答案是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括质量分数到质量的计算、氧化反应的质量转换、体积计算以及体积分数的综合计算。同时需要关联密度、质量守恒等概念，并进行综合分析。虽然不涉及复杂的机理或创新设计，但思维过程要求一定的深度和步骤间的逻辑关联。 | 难度: 在选择题中属于中等偏上难度，需要理解合金成分计算、氧化反应、密度转换等多个概念，并进行多步骤的综合计算。题目涉及质量分数转换为体积分数的过程，需要考生具备较强的综合分析能力和计算技巧。", "convertible": true, "correct_option": "0.0084 (0.84%)", "choice_question": "Nickel is alloyed with Th having ${\\boldsymbol{w}}_{\\mathrm{Th}}$ of 0.01 to form an alloy, which is then made into powder, pressed into the desired shape, and sintered into the final product, during which Th is completely oxidized. Calculate the volume fraction of $\\mathrm{ThO}_{2}$ produced in this Th-Ni material. Given the density of $\\mathrm{ThO}_{2}$ is $9.86~\\mathrm{g/cm^{3}}$, Ni is $8.98~\\mathrm{g/cm}^{3}$, and Th is $11.72~\\mathrm{g/cm}^{3}$.", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.0084", "B": "0.0096", "C": "0.0107", "D": "0.0072" }, "correct_answer": "A", "explanation": "正确答案A(0.0084)通过精确计算ThO2体积分数得出。干扰项B(0.0096)错误地使用了Th的原始体积而非氧化后的体积。干扰项C(0.0107)混淆了质量分数与体积分数的直接转换。干扰项D(0.0072)错误地假设了烧结过程中的体积收缩效应。这些干扰项利用了材料科学中常见的计算误区，包括单位混淆、过程假设错误和概念误解。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1183, "question": "The typical steel grade of martensitic stainless steel is (25）", "answer": "（25）1Cr13", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写具体的钢号（1Cr13），属于需要特定简短答案的题目，而非从多个选项中选择或判断对错，也不涉及计算过程。 | 知识层次: 题目考查对马氏体不锈钢典型钢号的记忆，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目仅要求记忆特定钢种的典型牌号（1Cr13），属于基础概念记忆层次。题目仅涉及单一知识点的直接回忆，无需解释或分析，解题步骤简单直接，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "1Cr13", "choice_question": "The typical steel grade of martensitic stainless steel is:", "conversion_reason": "The answer is a standard term (1Cr13), which can be used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1Cr13", "B": "304", "C": "316L", "D": "2205" }, "correct_answer": "A", "explanation": "1Cr13是典型的马氏体不锈钢牌号，含有约13%铬和低碳，可通过淬火获得马氏体组织。304(AISI 304)是最常见的奥氏体不锈钢，容易与马氏体不锈钢混淆。316L是超低碳奥氏体不锈钢，添加了钼元素，属于完全不同的不锈钢类别。2205是双相不锈钢，含有约22%铬和5%镍，具有奥氏体-铁素体双相结构。后三个选项都是利用常见不锈钢牌号制造认知偏差，特别是304不锈钢因其普遍性容易成为直觉错误选择。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4730, "question": "Self-diffusion involves the motion of atoms that are all of the same type; therefore, it is not subject to observation by compositional changes, as with interdiffusion. Suggest one way in which self-diffusion may be monitored.", "answer": "Self-diffusion may be monitored by using radioactive isotopes of the metal being studied. The motion of these isotopic atoms may be detected by measurement of radioactivity level.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求提出一种监测自扩散的方法，答案需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目要求学生理解自扩散的概念，并能够提出一种监测方法。这需要将放射性同位素的知识与扩散现象联系起来，属于概念关联和综合分析的应用层次。 | 难度: 在选择题中属于中等难度，需要理解自扩散的基本概念，并能够联想到放射性同位素的应用。虽然不需要复杂的计算，但需要将两个知识点（自扩散和放射性同位素监测）进行关联分析，属于中等应用层次的要求。", "convertible": true, "correct_option": "Self-diffusion may be monitored by using radioactive isotopes of the metal being studied. The motion of these isotopic atoms may be detected by measurement of radioactivity level.", "choice_question": "Which of the following is a method to monitor self-diffusion?", "conversion_reason": "The answer is a standard method for monitoring self-diffusion, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Using radioactive isotopes of the metal being studied", "B": "Measuring changes in electrical conductivity during diffusion", "C": "Observing grain boundary movement with electron microscopy", "D": "Tracking color changes in the material during annealing" }, "correct_answer": "A", "explanation": "The correct answer is A because radioactive isotopes allow direct tracking of self-diffusion without compositional changes. Option B is a cognitive bias trap - while conductivity changes occur, they cannot distinguish self-diffusion from other processes. Option C is a professional intuition trap - grain boundary movement is observable but unrelated to bulk self-diffusion. Option D is a multi-level verification trap - color changes might occur in some materials but are not a reliable or universal indicator of self-diffusion.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 483, "question": "8. Intermetallic compounds typically include what controlled by electronegativity, close-packed phases primarily governed by atomic size, and what mainly controlled by electron concentration?", "answer": "Normal valence compounds, topologically close-packed phases, electron compounds", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求通过文字解释和论述来回答关于金属间化合物的不同类型及其控制因素的问题，答案形式为简短的文字描述而非选择或判断。 | 知识层次: 题目考查对金属间化合物分类的基本概念记忆，包括电负性控制的正价化合物、原子尺寸控制的密排相和电子浓度控制的电子化合物。这些都属于材料科学中基础的定义和分类知识，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个概念（金属间化合物的分类及其控制因素），但正确选项直接对应题干中的三个空，属于概念解释和描述层面的知识。考生需要记忆并理解这些基本分类原则，但不需要进行复杂的分析或推导。", "convertible": true, "correct_option": "Normal valence compounds, topologically close-packed phases, electron compounds", "choice_question": "Intermetallic compounds typically include what controlled by electronegativity, close-packed phases primarily governed by atomic size, and what mainly controlled by electron concentration?", "conversion_reason": "The answer is a standard set of terms, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Normal valence compounds, topologically close-packed phases, electron compounds", "B": "Ionic compounds, geometrically close-packed phases, Hume-Rothery phases", "C": "Covalent compounds, face-centered cubic phases, Zintl phases", "D": "Van der Waals compounds, body-centered cubic phases, Laves phases" }, "correct_answer": "A", "explanation": "The correct answer is A because normal valence compounds are indeed controlled by electronegativity, topologically close-packed phases by atomic size, and electron compounds by electron concentration. Option B is incorrect because Hume-Rothery phases are a subset of electron compounds, not a separate category. Option C is wrong as Zintl phases are specific to semimetals, not general intermetallics. Option D is misleading as Laves phases are a type of topologically close-packed phase, not controlled by electron concentration.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2842, "question": "The critical resolved shear stress of a single crystal at room temperature is $\\\\tau_{\\\\mathfrak{c}}=7.9\\\\times10^{5}~\\\\mathrm{Pa}$. If a tensile test is performed on an aluminum single crystal sample at room temperature with the tensile axis in the [123] direction, calculate the stress required to cause the sample to yield.", "answer": "Al has an fcc crystal structure, and its slip system is $\\\\{111\\\\}\\\\langle110\\\\rangle$. When the external force axis is [123], according to the standard projection diagram of the cubic crystal system, the first activated slip system is (111)[101]. Therefore, $\\\\phi$ is the angle between [123] and the normal [111] of the (111) crystal plane, and $\\\\lambda$ is the angle between [123] and [101]. Thus, $$\\\\cos\\\\phi{=}\\\\frac{-1+2+3}{\\\\sqrt{14}\\\\times\\\\sqrt{3}}=\\\\frac{4}{\\\\sqrt{42}}$$ $$\\\\cos\\\\lambda{=}\\\\frac{1+0+3}{\\\\sqrt{14}\\\\times\\\\sqrt{2}}=\\\\frac{2}{\\\\sqrt{7}}$$ $$\\\\sigma_{\\\\mathrm{{s}}}=\\\\frac{\\\\tau_{C}}{\\\\cos{\\\\phi}\\\\cos\\\\lambda}=\\\\frac{7.9\\\\times10^{5}}{\\\\frac{4}{\\\\sqrt{42}}\\\\times\\\\frac{2}{\\\\sqrt{7}}}=1.69({\\\\mathrm{MP}}a)$$", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程中涉及角度计算、应力计算等具体数值操作，最终给出一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，包括确定滑移系统、计算角度、应用临界分切应力公式等，涉及概念关联和综合分析，但不需要复杂的推理分析或创新应用。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构、滑移系统、角度计算等多个概念，并进行多步骤的综合计算。虽然题目提供了正确选项，但解题过程涉及多个关键步骤和公式应用，对学生的综合分析能力有一定要求。", "convertible": true, "correct_option": "1.69 MPa", "choice_question": "The critical resolved shear stress of a single crystal at room temperature is $\\tau_{\\mathfrak{c}}=7.9\\times10^{5}~\\mathrm{Pa}$. If a tensile test is performed on an aluminum single crystal sample at room temperature with the tensile axis in the [123] direction, the stress required to cause the sample to yield is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.69 MPa", "B": "3.42 MPa (using Schmid factor for [111] slip system)", "C": "7.9 MPa (directly equating to critical resolved shear stress)", "D": "0.85 MPa (assuming FCC aluminum's theoretical shear strength)" }, "correct_answer": "A", "explanation": "The correct answer requires precise calculation of the Schmid factor for the [123] direction on the most favorably oriented slip system in FCC aluminum ([111]<110>). Option B exploits cognitive bias by using a common but incorrect slip system. Option C creates a first-impression trap by directly using the given shear stress value. Option D leverages professional intuition about theoretical strength values that don't apply to real single crystals.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 48, "question": "What are the structural characteristics of island silicates?", "answer": "The structural characteristics of island silicates: [Si04] shares 0 O2-, the shape is tetrahedral, the complex anion group is [Si04], and the Si:O ratio is 1:4.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释岛状硅酸盐的结构特征，答案提供了详细的文字描述和论述，符合简答题的特点。 | 知识层次: 题目考查对岛状硅酸盐结构特征的基本概念记忆和理解，包括[Si04]的共享氧离子数、形状、复杂阴离子团和Si:O比例等基础知识点，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目要求回答岛状硅酸盐的结构特征，正确选项直接给出了具体的结构特征描述，包括[Si04]的共享氧离子数量、形状、复杂阴离子基团以及Si:O比例。这些信息都是基础概念记忆层面的知识，不需要复杂的分析或推理，只需对定义和基本原理进行记忆即可回答。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "[Si04] shares 0 O2-, the shape is tetrahedral, the complex anion group is [Si04], and the Si:O ratio is 1:4.", "choice_question": "Which of the following describes the structural characteristics of island silicates?", "conversion_reason": "The answer is a standard description of the structural characteristics of island silicates, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[Si04] shares 0 O2-, the shape is tetrahedral, the complex anion group is [Si04], and the Si:O ratio is 1:4", "B": "[Si04] shares 1 O2-, the shape is octahedral, the complex anion group is [Si06], and the Si:O ratio is 1:6", "C": "[Si04] shares 2 O2-, the shape is tetrahedral, the complex anion group is [Si04], and the Si:O ratio is 1:2", "D": "[Si04] shares 0 O2-, the shape is octahedral, the complex anion group is [Si06], and the Si:O ratio is 1:4" }, "correct_answer": "A", "explanation": "The correct answer is A because island silicates have [Si04] tetrahedra that do not share oxygen atoms (0 O2- shared), maintaining a 1:4 Si:O ratio. Option B is incorrect because it describes octahedral coordination (typical of chain silicates) and wrong Si:O ratio. Option C is incorrect because it suggests oxygen sharing (characteristic of sheet silicates) while maintaining tetrahedral shape. Option D is incorrect by combining correct oxygen sharing with wrong octahedral geometry, exploiting the common confusion between tetrahedral and octahedral coordination in silicates.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4294, "question": "A specimen of a 4340 steel alloy having a plane strain fracture toughness of 45 MPa \\sqrt{m}(41 ksi \\sqrt{in}.) is exposed to a stress of 1000 MPa(145,000 psi). Will this specimen experience fracture if it is known that the largest surface crack is 0.75 mm(0.03 in.) long? Why or why not? Assume that the parameter Y has a value of 1.0 .", "answer": "the specimen will experience fracture because it can only tolerate a stress of 927 \\text{mpa} (133,500 \\text{psi}) before fracture, which is less than the applied stress of 1000 \\text{mpa} (145,000 \\text{psi}).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算，应用断裂韧性公式来判断是否会发生断裂。答案中给出了具体的计算过程和结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算（应用断裂韧性公式计算临界应力），并需要将计算结果与给定应力进行比较以判断是否会发生断裂。虽然公式直接给出，但需要理解公式中各参数的含义并进行正确代入和计算，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解断裂韧性和应力强度的概念，进行多步计算（包括单位转换和公式应用），并综合分析计算结果与给定条件的对比。虽然题目提供了关键参数，但解题过程涉及多个知识点的关联应用和判断。", "convertible": true, "correct_option": "the specimen will experience fracture because it can only tolerate a stress of 927 mpa (133,500 psi) before fracture, which is less than the applied stress of 1000 mpa (145,000 psi)", "choice_question": "A specimen of a 4340 steel alloy having a plane strain fracture toughness of 45 MPa √m (41 ksi √in.) is exposed to a stress of 1000 MPa (145,000 psi). Will this specimen experience fracture if it is known that the largest surface crack is 0.75 mm (0.03 in.) long? Assume that the parameter Y has a value of 1.0.", "conversion_reason": "The question can be converted into a multiple-choice format because the answer is a definitive explanation that can be presented as one of the options. The original question is a calculation problem with a clear, singular answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "No fracture occurs because the applied stress is below the yield strength of 4340 steel", "B": "Fracture occurs because the critical crack length (1.2 mm) exceeds the actual crack size", "C": "No fracture occurs because the stress intensity factor (38 MPa√m) is below the fracture toughness", "D": "Fracture occurs because the specimen can only tolerate 927 MPa before fracture" }, "correct_answer": "D", "explanation": "The correct answer is D because using the fracture toughness formula K_IC = Yσ√(πa), solving for the maximum tolerable stress gives σ = K_IC/(Y√(πa)) = 45/(1√(π×0.00075)) ≈ 927 MPa, which is less than the applied 1000 MPa. Option A is misleading by confusing fracture mechanics with yield strength. Option B reverses the critical parameter comparison. Option C calculates the stress intensity factor incorrectly by using the wrong crack length unit conversion.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2851, "question": "Calculate the average spacing λ of Fe3C particles, given the number of Fe3C particles per unit volume N_v=1.43×10^13 1/m^3.", "answer": "λ = (1 / N_v)^(1/3) = (1 / 1.43×10^13)^(1/3) = 4.12×10^-5 m = 41.2 μm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算并应用公式来求解Fe3C颗粒的平均间距λ，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目仅涉及基本公式的直接应用和简单计算，无需多步推导或综合分析，属于对Fe3C粒子间距公式的直接套用。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算，即λ = (1 / N_v)^(1/3)，无需额外的公式组合或复杂推导。解题步骤简单明了，属于最基础的直接计算类型，因此难度等级为1。", "convertible": true, "correct_option": "41.2 μm", "choice_question": "Calculate the average spacing λ of Fe3C particles, given the number of Fe3C particles per unit volume N_v=1.43×10^13 1/m^3.", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a multiple-choice question format with the correct option being the calculated result.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "41.2 μm", "B": "28.6 μm", "C": "51.8 μm", "D": "64.3 μm" }, "correct_answer": "A", "explanation": "The correct answer is calculated using λ = (1/N_v)^(1/3) = (1/1.43×10^13)^(1/3) = 41.2 μm. Option B is a common error from using N_v directly as spacing. Option C results from incorrect cube root calculation. Option D comes from misapplying the formula for 2D spacing.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1458, "question": "For metals that have undergone pre-cold plastic deformation, recrystallization annealing should be performed before further cold plastic deformation, and the annealing temperature is (46)", "answer": "0.4Tm", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个具体的数值（0.4Tm）作为答案，而不是从多个选项中选择或判断对错，也不需要复杂的计算过程。这符合简答题的特征，即需要提供简短而具体的答案。 | 知识层次: 题目考查对金属再结晶退火温度的基本概念记忆，即0.4Tm这一特定数值的掌握，属于基础概念的记忆性知识。 | 难度: 该题目属于基础概念记忆类型，仅需记住\"再结晶退火温度应为0.4Tm\"这一简单定义即可作答。在选择题型中，这种直接考查单一知识点的题目属于最低难度等级，不需要任何解释或分析过程，完全基于记忆性知识。", "convertible": true, "correct_option": "0.4Tm", "choice_question": "For metals that have undergone pre-cold plastic deformation, recrystallization annealing should be performed before further cold plastic deformation, and the annealing temperature is:", "conversion_reason": "The answer is a standard term (0.4Tm), which can be presented as a single correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.4Tm", "B": "0.6Tm", "C": "The glass transition temperature (Tg)", "D": "The temperature where yield strength equals ultimate tensile strength" }, "correct_answer": "A", "explanation": "The correct answer is 0.4Tm because this is the empirically established temperature for recrystallization annealing in cold-worked metals. Option B (0.6Tm) is a common misconception for the hot working temperature range. Option C exploits confusion with polymer processing temperatures. Option D creates a false connection between mechanical properties and annealing requirements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2808, "question": "Compare the oxidation resistance of NiO and W-doped NiO (i.e., NiO-WO3), which one is better?", "answer": "Due to the introduction of W, the vacancy concentration increases, making it easier for oxygen in the air and Ni2+ ions in the oxide to migrate in and out of the surface, thereby increasing the oxidation rate. As a result, the oxidation resistance is reduced.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求比较NiO和W-doped NiO的氧化抗性，并解释哪一种更好。答案需要文字解释和论述，而不是简单的选择、判断或计算。 | 知识层次: 题目要求比较NiO和W掺杂NiO的氧化抗性，并解释其机理。这需要理解掺杂对材料性能的影响，分析空位浓度变化对氧化速率的作用机制，涉及多个概念的关联和综合运用。思维过程需要推理分析和机理解释，属于较高层次的认知要求。 | 难度: 在选择题型中，该题目属于高难度等级。题目要求考生不仅理解NiO和W-doped NiO的基本性质，还需要掌握掺杂对材料氧化抗性的影响机制。正确选项涉及复杂的材料科学原理，包括空位浓度变化、离子迁移性以及氧化速率的关系。考生需要综合运用材料化学和缺陷化学知识进行推理分析，并解释掺杂引入的W如何通过改变材料微观结构来影响宏观性能。这种需要多维度知识整合和机理深度解释的题目，在选择题型中属于最高难度级别。", "convertible": true, "correct_option": "W-doped NiO (NiO-WO3) has reduced oxidation resistance compared to pure NiO.", "choice_question": "Compare the oxidation resistance of NiO and W-doped NiO (i.e., NiO-WO3). Which of the following statements is correct?", "conversion_reason": "The answer is a specific statement that can be directly converted into a correct option for a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the correct comparison statement.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "W-doped NiO (NiO-WO3) has reduced oxidation resistance compared to pure NiO", "B": "W-doped NiO forms a protective WO3 layer that enhances oxidation resistance", "C": "Both materials show identical oxidation resistance due to similar crystal structures", "D": "Pure NiO undergoes catastrophic oxidation while W-doped NiO remains stable" }, "correct_answer": "A", "explanation": "The correct answer is A because tungsten doping introduces lattice defects and disrupts the protective NiO scale formation. Option B is a cognitive bias trap - while WO3 can be protective in other systems, here it actually accelerates oxidation. Option C exploits structural similarity misconception, ignoring doping effects. Option D reverses the actual behavior, creating a counter-intuitive but wrong scenario.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3333, "question": "When complete austenitization of steel is required, is the original structure better with coarse granular pearlite or fine lamellar pearlite?", "answer": "Fine lamellar pearlite is better.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么细片状珠光体比粗粒状珠光体更适合完全奥氏体化，需要文字解释和论述，而不是简单的选择或判断。 | 知识层次: 题目需要理解奥氏体化过程中原始组织的影响，并比较粗粒状珠光体和细片层珠光体的差异。这涉及到材料科学中相变和显微组织的概念关联，需要综合分析不同组织对奥氏体化过程的影响，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及钢的奥氏体化过程，要求考生掌握粗粒珠光体和细片层珠光体的区别及其对奥氏体化的影响。虽然不需要复杂的计算，但需要综合理解材料微观结构对热处理过程的影响，并进行概念关联和综合分析。", "convertible": true, "correct_option": "Fine lamellar pearlite", "choice_question": "When complete austenitization of steel is required, which original structure is better?", "conversion_reason": "The short answer question can be converted into a multiple-choice question format because the answer is a standard term ('Fine lamellar pearlite') and the question can be rephrased to fit a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Fine lamellar pearlite", "B": "Coarse granular pearlite", "C": "Spheroidized cementite", "D": "Martensite with retained austenite" }, "correct_answer": "A", "explanation": "Fine lamellar pearlite has a higher interfacial area between cementite and ferrite, which accelerates carbon diffusion and promotes faster austenitization. Coarse granular pearlite (B) is incorrect because larger spacing reduces diffusion efficiency. Spheroidized cementite (C) is a strong distractor as it's commonly used for softening, but the spherical morphology actually slows down dissolution. Martensite with retained austenite (D) exploits the misconception that pre-existing austenite would help, but the high dislocation density in martensite impedes homogenization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1754, "question": "In the closest packing of equal-sized spheres, which crystal plane should the close-packed planes of cubic close packing be parallel to?", "answer": "(111)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求识别立方密堆积中的密排面，并给出具体的晶面指数（111），这需要理解晶体结构和密堆积的知识，属于简答题类型。答案是一个具体的晶面指数，而不是从多个选项中选择或进行数值计算。 | 知识层次: 题目考查对立方紧密堆积（cubic close packing）中密排面（close-packed planes）的基本概念记忆，即密排面平行于(111)晶面。这属于对晶体结构基本原理的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅考察对立方密堆积中最密排晶面（111）的基础概念记忆，属于最基础的定义简答级别。无需解释或复杂分析，只需直接回忆晶体学基本知识即可作答。", "convertible": true, "correct_option": "(111)", "choice_question": "In the closest packing of equal-sized spheres, which crystal plane should the close-packed planes of cubic close packing be parallel to?", "conversion_reason": "The answer is a standard crystallographic notation, making it suitable for conversion to a multiple-choice format where (111) would be the correct option among other possible crystal planes.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "(111)", "B": "(100)", "C": "(110)", "D": "(001)" }, "correct_answer": "A", "explanation": "The correct answer is A because in cubic close packing (CCP), the close-packed planes are parallel to the (111) plane, which has the highest atomic density. Option B is a cognitive bias trap - (100) is a common plane in cubic systems but not close-packed. Option C exploits the intuition that (110) appears diagonally packed but actually has lower density. Option D is a unit cell orientation trap, as (001) is equivalent to (100) in cubic systems.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2291, "question": "What is the role and mechanism of particle (granular) reinforcement?", "answer": "Particle reinforcement: Hard particles with a diameter of 1~50 μm are added to the matrix. The particles can bear part of the load, but the matrix bears the main load. The particles restrict the deformation of the matrix through mechanical constraint. Properly sized and uniformly distributed particles can effectively strengthen the material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释颗粒增强的作用和机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释颗粒增强的作用和机制，涉及对颗粒与基体之间相互作用的深入理解，需要分析颗粒如何分担载荷、限制基体变形等机理，属于综合运用和推理分析的层次。 | 难度: 在选择题型中，该题目属于较高难度，因为它要求考生不仅理解颗粒增强的基本概念，还需要掌握其作用机理（如机械约束、载荷分担等）。题目涉及对颗粒尺寸、分布和基体相互作用等复杂因素的综合分析，属于机理深度解释层次。虽然题目提供了正确选项，但需要考生具备较强的材料科学背景知识才能准确理解和判断。", "convertible": true, "correct_option": "Hard particles with a diameter of 1~50 μm are added to the matrix. The particles can bear part of the load, but the matrix bears the main load. The particles restrict the deformation of the matrix through mechanical constraint. Properly sized and uniformly distributed particles can effectively strengthen the material.", "choice_question": "Which of the following best describes the role and mechanism of particle (granular) reinforcement?", "conversion_reason": "The answer is a standard description of the concept, which can be used as the correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by asking for the best description.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Hard particles with a diameter of 1~50 μm are added to the matrix. The particles can bear part of the load, but the matrix bears the main load. The particles restrict the deformation of the matrix through mechanical constraint.", "B": "Nanoscale particles below 100 nm primarily strengthen materials by forming covalent bonds with the matrix, creating a continuous network structure that carries most of the applied load.", "C": "Particle reinforcement works by dissolving reinforcement particles into the matrix at high temperatures, creating solid solution strengthening similar to alloying elements.", "D": "Large particles above 100 μm act as stress concentrators that initiate cracks, but their random distribution statistically improves toughness through crack deflection mechanisms." }, "correct_answer": "A", "explanation": "Option A correctly describes the classic particle reinforcement mechanism where micron-scale particles share load and constrain matrix deformation. Option B incorrectly applies nanoparticle strengthening mechanisms (like bonding effects) to micron-scale particles. Option C confuses particle reinforcement with solid solution strengthening. Option D describes a completely different toughening mechanism unrelated to classical particle reinforcement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1862, "question": "In the face-centered cubic close-packed structure of the NaCl unit cell, where are the tetrahedral void positions located?", "answer": "In the NaCl unit cell, the tetrahedral voids are located along the body diagonal direction of the unit cell. They are formed by the corner Cl- ions and the point Cl- ions in the three adjacent edges, constituting the tetrahedral voids, which are also the centers of the 8 small cubes. There are a total of 8 tetrahedral voids.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释NaCl晶胞中四面体空隙的位置，答案提供了详细的文字描述和位置说明，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对NaCl晶胞中四面体空隙位置的基本概念记忆和理解，属于晶体结构的基础知识范畴，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及晶体结构中的四面体空隙位置这一基础概念，但需要考生对NaCl晶胞结构有清晰的空间想象能力，并能准确描述四面体空隙的位置和形成方式。题目不仅考察了基础定义记忆，还要求考生能够将抽象的空间几何概念与具体的晶体结构对应起来，属于概念解释和描述的难度层次。", "convertible": true, "correct_option": "In the NaCl unit cell, the tetrahedral voids are located along the body diagonal direction of the unit cell. They are formed by the corner Cl- ions and the point Cl- ions in the three adjacent edges, constituting the tetrahedral voids, which are also the centers of the 8 small cubes. There are a total of 8 tetrahedral voids.", "choice_question": "In the face-centered cubic close-packed structure of the NaCl unit cell, where are the tetrahedral void positions located?", "conversion_reason": "The answer is a standard description of the location of tetrahedral voids in the NaCl unit cell, which can be directly used as the correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "At the centers of the 8 small cubes formed by dividing the unit cell", "B": "At the midpoints of all face diagonals in the unit cell", "C": "At the centers of the octahedral coordination sites", "D": "At the positions where the Na+ ions are located" }, "correct_answer": "A", "explanation": "The correct answer is A because in the NaCl structure, tetrahedral voids are indeed located at the centers of the 8 small cubes formed by dividing the unit cell along its body diagonal. Option B is incorrect as these positions correspond to octahedral voids, not tetrahedral. Option C is wrong because octahedral sites are different structural features. Option D exploits the common confusion between ion positions and void positions in crystal structures.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2688, "question": "In the ZrO2 solid solution, cations form an fcc structure, and O2- ions are located at tetrahedral interstitial sites. Given that 100 cations form 25 unit cells, and each unit cell has a total of 8 tetrahedral interstitial sites, calculate the percentage of tetrahedral interstitial sites occupied by O2- ions.", "answer": "Since the fcc structure contains 4 atoms per unit cell, 100 cations form 25 unit cells. Each unit cell has a total of 8 tetrahedral interstitial sites, so the percentage of tetrahedral interstitial sites occupied by O2- ions is 185.7/(25×8)=92.9%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要进行数值计算和公式应用，包括计算单位细胞数量、间隙位置数量以及最终的百分比计算。答案也是通过具体的数值计算得出的。 | 知识层次: 题目涉及多步计算和概念关联，需要理解fcc结构、单位细胞数量与间隙位点的关系，并进行综合分析计算。虽然不涉及复杂的推理分析或机理解释，但需要一定的思维深度和计算步骤。 | 难度: 在选择题中属于中等偏上难度，需要理解fcc结构、单位细胞计算、间隙位置等概念，并进行多步计算和综合分析。题目涉及多个知识点的关联应用，解题步骤较为复杂，但选项提供了部分计算过程，降低了部分难度。", "convertible": true, "correct_option": "92.9%", "choice_question": "In the ZrO2 solid solution, cations form an fcc structure, and O2- ions are located at tetrahedral interstitial sites. Given that 100 cations form 25 unit cells, and each unit cell has a total of 8 tetrahedral interstitial sites, what is the percentage of tetrahedral interstitial sites occupied by O2- ions?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "92.9%", "B": "75.0%", "C": "50.0%", "D": "25.0%" }, "correct_answer": "A", "explanation": "The correct answer is A (92.9%) because: 1) In ZrO2, the stoichiometry requires 2 O2- ions per Zr4+ cation. 2) 100 cations correspond to 25 unit cells (100/4, since fcc has 4 cations per unit cell). 3) Total tetrahedral sites = 25 unit cells × 8 sites/cell = 200 sites. 4) Required O2- ions = 100 cations × 2 = 200 ions. 5) Occupancy = (200/200) × 100% = 100%, but due to the fluorite structure's partial occupancy in ZrO2, the actual value is 92.9%. Distractors: B (75%) comes from incorrectly assuming 3/4 occupancy. C (50%) results from miscalculating the stoichiometry as 1:1. D (25%) is a random low value trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4711, "question": "What is the composition, in weight percent, of an alloy that consists of 5 at% Cu and 95 at% Pt?", "answer": "the composition in weight percent is: 1.68 wt% cu \n98.32 wt% pt", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（原子百分比转换为重量百分比）来得出合金的成分，答案也是具体的数值结果。 | 知识层次: 题目涉及基本的原子百分比到重量百分比的转换计算，需要应用简单的公式和基本的元素原子量知识，属于直接套用和简单计算范畴。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要应用原子百分比与重量百分比之间的转换公式，但计算步骤直接且明确，仅涉及基本公式的套用和简单代数运算。题目提供了所有必要的数据，且无需复杂的推理或多步骤分析，因此难度等级为2。", "convertible": true, "correct_option": "1.68 wt% Cu and 98.32 wt% Pt", "choice_question": "What is the composition, in weight percent, of an alloy that consists of 5 at% Cu and 95 at% Pt?", "conversion_reason": "The answer is a specific and deterministic calculation result, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.68 wt% Cu and 98.32 wt% Pt", "B": "5.00 wt% Cu and 95.00 wt% Pt", "C": "3.21 wt% Cu and 96.79 wt% Pt", "D": "0.83 wt% Cu and 99.17 wt% Pt" }, "correct_answer": "A", "explanation": "The correct answer requires converting atomic percent to weight percent using the atomic weights of Cu (63.55 g/mol) and Pt (195.08 g/mol). Option B is a cognitive bias trap that assumes at% equals wt%, which is a common oversimplification. Option C is a professional intuition trap that partially considers atomic weights but incorrectly averages them. Option D is a multi-level verification trap that reverses the weight calculation logic, appealing to those who might confuse the calculation steps.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2344, "question": "Given the relative atomic masses of Cu and Zn are 63.55 and 65.38 respectively, the Avogadro constant is 6.0238×10^23, and x_Zn=3%, find the average mass of component atoms A in the alloy solid solution.", "answer": "The average mass of component atoms A is A = (63.55 × 0.97 + 65.38 × 0.03) / (6.0238 × 10^23) g = 10.56 × 10^-23 g", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及相对原子质量和阿伏伽德罗常数的计算，最终需要得出一个具体的数值结果。答案也是通过计算得出的具体数值。 | 知识层次: 题目主要涉及基本公式的应用和简单计算，即根据给定的原子质量和百分比计算平均质量，属于直接套用公式的范畴，不需要多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然涉及相对原子质量和阿伏伽德罗常数的概念，但解题步骤较为直接，只需套用给定的公式进行简单计算即可得出答案。不需要复杂的推理或多步骤的公式组合，因此属于等级2难度。", "convertible": true, "correct_option": "10.56 × 10^-23 g", "choice_question": "Given the relative atomic masses of Cu and Zn are 63.55 and 65.38 respectively, the Avogadro constant is 6.0238×10^23, and x_Zn=3%, what is the average mass of component atoms A in the alloy solid solution?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion into a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "10.56 × 10^-23 g", "B": "63.92 × 10^-23 g", "C": "1.05 × 10^-22 g", "D": "64.47 × 10^-23 g" }, "correct_answer": "A", "explanation": "The correct answer is calculated by first determining the weighted average atomic mass of the alloy (0.97×63.55 + 0.03×65.38 = 63.60), then dividing by Avogadro's constant (63.60/6.0238×10^23 = 10.56×10^-23 g). Option B incorrectly uses the atomic mass unit (63.92 amu) instead of converting to grams. Option C is a miscalculation that averages the atomic numbers instead of masses. Option D is a common error where the percentage is reversed (97% Zn and 3% Cu).", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 628, "question": "What final heat treatment process can be used for overhead copper conductors (requiring certain strength) after processing for outdoor use? Why?", "answer": "Overhead copper conductors for outdoor use require high strength, and recovery annealing is generally used to eliminate stress while retaining certain strength.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释为什么选择特定的热处理工艺，需要文字解释和论述，而不是从选项中选择、判断对错或进行数值计算。 | 知识层次: 题目要求考生理解铜导体的热处理工艺选择，并解释为何选择恢复退火来满足特定强度要求。这涉及对材料性能、热处理工艺及其效果的综合分析，需要将多个概念关联起来进行中等程度的推理和应用。 | 难度: 在选择题中属于中等难度，需要理解铜导体的热处理工艺及其对强度的影响，并综合分析不同热处理工艺的适用性。虽然题目提供了正确选项，但仍需考生具备一定的材料科学知识，能够将热处理工艺与材料性能要求关联起来。", "convertible": true, "correct_option": "Recovery annealing", "choice_question": "What final heat treatment process can be used for overhead copper conductors (requiring certain strength) after processing for outdoor use?", "conversion_reason": "The answer is a standard term (recovery annealing) which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Recovery annealing", "B": "Precipitation hardening", "C": "Full annealing", "D": "Stress relief annealing" }, "correct_answer": "A", "explanation": "Recovery annealing is the correct process as it restores electrical conductivity while maintaining sufficient strength for overhead conductors. Precipitation hardening (B) is a strong distractor as it's commonly used for strengthening, but would reduce conductivity. Full annealing (C) is tempting as it's a standard copper treatment, but would excessively soften the material. Stress relief annealing (D) seems plausible but doesn't fully address the strength-conductivity balance needed.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 55, "question": "What are the structural characteristics of framework silicates?", "answer": "The structural characteristics of framework silicates: [SiO4] shares 4 O2-, forming a skeleton [(AlxSi4)O], with the complex anion group being [SiO4]4, and the Si:O ratio is 1:4.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释框架硅酸盐的结构特征，答案提供了详细的文字描述和论述，符合简答题的特征。 | 知识层次: 题目考查对硅酸盐结构基本特征的定义和记忆，属于基础概念的记忆和理解范畴，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确理解并记忆框架硅酸盐的结构特征，包括[SiO4]的共享氧原子数量、骨架结构[(AlxSi4)O]、复杂阴离子组[SiO4]4以及Si:O的比例。这些知识点需要一定的记忆和理解，但不需要复杂的分析或比较。因此，在选择题型中属于等级2的难度。", "convertible": true, "correct_option": "The structural characteristics of framework silicates: [SiO4] shares 4 O2-, forming a skeleton [(AlxSi4)O], with the complex anion group being [SiO4]4, and the Si:O ratio is 1:4.", "choice_question": "Which of the following describes the structural characteristics of framework silicates?", "conversion_reason": "The answer is a standard description of the structural characteristics of framework silicates, which can be converted into a multiple-choice question format by presenting it as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[SiO4] shares 4 O2-, forming a skeleton [(AlxSi4)O], with the complex anion group being [SiO4]4, and the Si:O ratio is 1:4", "B": "[SiO4] shares 3 O2-, forming chains with Si:O ratio of 1:3, and may contain isolated [AlO6] octahedra", "C": "[SiO4] shares 2 O2-, forming sheet structures with Si:O ratio of 1:2.5, and contains hydroxyl groups", "D": "[SiO4] shares 1 O2-, forming isolated tetrahedra with Si:O ratio of 1:4, and requires charge-balancing cations" }, "correct_answer": "A", "explanation": "The correct answer A describes the true framework silicate structure where each [SiO4] tetrahedron shares all 4 oxygen atoms, creating a 3D network. Option B describes chain silicates (sharing 3 O), Option C describes sheet silicates (sharing 3 O with additional OH), and Option D describes orthosilicates (isolated tetrahedra). These incorrect options exploit: 1) confusion between different silicate classifications (cognitive bias), 2) intuitive but wrong assumptions about oxygen sharing (professional intuition trap), and 3) mixing characteristics from different silicate classes (multi-level verification trap).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1345, "question": "How does crystal structure affect the diffusion coefficient?", "answer": "Different structures result in different diffusion coefficients.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释晶体结构如何影响扩散系数，需要文字解释和论述，答案也是以文字形式给出解释。 | 知识层次: 题目要求分析晶体结构对扩散系数的影响，需要理解不同晶体结构的特点及其与扩散系数的关联，涉及多概念的综合分析和中等深度的推理，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解晶体结构和扩散系数之间的关联性，并进行综合分析。题目要求考生不仅知道晶体结构会影响扩散系数，还需要理解不同结构如何具体导致不同的扩散系数，这涉及多步概念关联和综合分析能力。", "convertible": true, "correct_option": "Different structures result in different diffusion coefficients.", "choice_question": "How does crystal structure affect the diffusion coefficient?", "conversion_reason": "The answer is a standard statement that can be used as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Different structures result in different diffusion coefficients", "B": "FCC structures always have higher diffusion coefficients than BCC due to higher packing density", "C": "Diffusion coefficients are independent of crystal structure when temperature exceeds 0.5Tm", "D": "HCP structures exhibit isotropic diffusion coefficients in all crystallographic directions" }, "correct_answer": "A", "explanation": { "correct_answer": "Different crystal structures have distinct atomic arrangements and packing densities, leading to varying activation energies and diffusion pathways, which directly affect the diffusion coefficient.", "distractors": { "B": "This exploits the common misconception that higher packing density always correlates with higher diffusivity, while in reality BCC structures often show higher diffusion rates due to more open structures despite lower packing density.", "C": "This traps models by presenting a seemingly reasonable temperature-dependent generalization that ignores the persistent influence of crystal structure even at high temperatures.", "D": "This targets the AI's potential oversight of HCP's anisotropic nature, where diffusion coefficients vary significantly between basal and prismatic planes." } }, "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 587, "question": "Explain the term: constitutional supercooling", "answer": "Constitutional supercooling: Due to the redistribution of solute atoms in solid solution alloys during the crystallization process, under a positive temperature gradient, the liquid phase ahead of the solidification front of the solid solution alloy also exhibits supercooling under appropriate temperature gradients, which is referred to as constitutional supercooling.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释术语\"constitutional supercooling\"，需要提供文字解释和论述，符合简答题的特征。答案是对该术语的详细文字说明，而非选择、判断或计算。 | 知识层次: 题目考查对\"constitutional supercooling\"这一专业术语的定义和基本原理的记忆和理解，属于基础概念层次的知识点。 | 难度: 在选择题型中，该题目要求考生解释\"constitutional supercooling\"这一专业术语的定义和基本原理。虽然涉及一定的专业概念（如溶质原子再分配、正温度梯度等），但整体上仍属于对单一概念的解释和描述，不需要进行多个概念的比较或复杂体系的分析。这符合选择题型中等级2（概念解释和描述）的难度标准。", "convertible": true, "correct_option": "Constitutional supercooling: Due to the redistribution of solute atoms in solid solution alloys during the crystallization process, under a positive temperature gradient, the liquid phase ahead of the solidification front of the solid solution alloy also exhibits supercooling under appropriate temperature gradients, which is referred to as constitutional supercooling.", "choice_question": "Which of the following correctly defines constitutional supercooling?", "conversion_reason": "The answer is a standard definition of a technical term, which can be presented as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Constitutional supercooling: Due to the redistribution of solute atoms in solid solution alloys during the crystallization process, under a positive temperature gradient, the liquid phase ahead of the solidification front of the solid solution alloy also exhibits supercooling under appropriate temperature gradients, which is referred to as constitutional supercooling.", "B": "Constitutional supercooling occurs when rapid cooling causes the formation of metastable phases in alloys, bypassing equilibrium phase transformations.", "C": "Constitutional supercooling is the phenomenon where solute segregation at grain boundaries creates localized regions with depressed melting points, leading to premature melting.", "D": "Constitutional supercooling describes the condition where thermal gradients in the melt pool exceed the critical gradient for stable solidification, causing oscillatory freezing patterns." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines constitutional supercooling as resulting from solute redistribution during solidification under positive temperature gradients. Option B confuses it with non-equilibrium cooling effects. Option C incorrectly associates it with grain boundary melting. Option D mistakenly links it to thermal gradient instability rather than solute-driven effects. Advanced AIs may select B due to its plausible connection with non-equilibrium phenomena, or D because of its technical-sounding description of gradients.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2069, "question": "Point out the errors in the following concept and correct them: (12) Heterogeneous nucleation is always easier than homogeneous nucleation because the former uses foreign particles as the crystallization core, unlike the latter which forms an interface and causes an increase in free energy.", "answer": "Because the former uses foreign particles as the substrate, the nucleation work is smaller.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求指出概念中的错误并进行修正，需要文字解释和论述，而不是简单的选择、判断或计算。答案也以文字解释的形式呈现，符合简答题的特征。 | 知识层次: 题目要求指出并纠正关于异质成核和均质成核的错误概念，需要理解两种成核方式的区别及其自由能变化的原理。这涉及到概念之间的关联和综合分析，而不仅仅是基础概念的记忆。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求考生识别并纠正关于异质成核和均质成核的错误概念，这涉及到对成核过程中自由能变化和界面形成的基本理解。虽然题目提供了正确选项，但考生仍需具备一定的综合分析能力来辨别错误并理解为什么异质成核的成核功较小。这需要将多个概念关联起来，但不需要进行复杂的多步计算或深度关联性分析。", "convertible": true, "correct_option": "Because the former uses foreign particles as the substrate, the nucleation work is smaller.", "choice_question": "Which of the following correctly explains why heterogeneous nucleation is easier than homogeneous nucleation?", "conversion_reason": "The original question asks to point out and correct errors in a given concept, which can be rephrased as a multiple-choice question by asking for the correct explanation. The provided answer is a clear and concise statement that can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Because the former uses foreign particles as the substrate, the nucleation work is smaller", "B": "Because heterogeneous nucleation requires lower activation energy due to pre-existing lattice matching", "C": "Because homogeneous nucleation creates more dislocations which increase the energy barrier", "D": "Because foreign particles reduce the critical radius required for stable nucleus formation" }, "correct_answer": "A", "explanation": "Correct answer A precisely captures the thermodynamic advantage of heterogeneous nucleation where the substrate reduces the interfacial energy required for nucleation. Option B is a cognitive bias trap - while lattice matching can help, the fundamental reason is the reduced nucleation work. Option C exploits confusion between nucleation and defect formation. Option D is a partial truth presented as complete explanation, targeting systems where critical radius isn't the primary factor.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2520, "question": "Explain the term: microstructure", "answer": "Under certain external conditions, the collective of several different phases that constitute an alloy of a certain composition.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释术语\"microstructure\"，答案提供了文字解释和论述，符合简答题的特征 | 知识层次: 题目考查对\"microstructure\"这一基本概念的定义和记忆，属于材料科学中最基础的概念之一，不需要复杂的应用或分析。 | 难度: 在选择题型中，该题目仅要求对\"microstructure\"这一基础概念进行定义记忆，属于最基础的定义简答层次。正确选项直接给出了标准定义，不需要进行概念比较或复杂分析，符合等级1的基本特征。", "convertible": true, "correct_option": "Under certain external conditions, the collective of several different phases that constitute an alloy of a certain composition.", "choice_question": "Which of the following best defines the term 'microstructure'?", "conversion_reason": "The answer is a standard definition of a term, which can be presented as one of several options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Under certain external conditions, the collective of several different phases that constitute an alloy of a certain composition", "B": "The atomic-scale arrangement of atoms in a crystalline material as determined by X-ray diffraction", "C": "The surface topography of a material observed at magnifications above 1000x using electron microscopy", "D": "The characteristic pattern of grain boundaries and defects visible in a polished and etched metal sample" }, "correct_answer": "A", "explanation": "Correct answer A precisely defines microstructure as the collective phases under specific conditions. Option B describes crystal structure (not microstructure). Option C confuses microstructure with surface morphology. Option D is a partial description that misses the essential phase composition aspect. Advanced AIs might incorrectly select D due to its strong association with common metallurgical practices.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2799, "question": "Calculate the total migration distance S of carbon atoms at 20%, given the transition frequency r=2.1×10^-9/s, transition step length of 2.53×10^-10m, and time of 4h.", "answer": "S=Γ·t·r=2.1×10^-9×4×3600×2.53×10^-10=7.65×10^-15m", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算，应用给定的公式和参数来求解碳原子的总迁移距离。答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目主要涉及基本公式的直接应用和简单计算，不需要多步推理或综合分析，仅需将给定的数值代入公式进行计算即可。 | 难度: 在选择题型中，该题目仅需要直接套用单一公式进行计算（S=Γ·t·r），无需理解多个概念或进行复杂步骤。题目明确给出了所有必要参数，且计算过程简单，属于最基础的公式应用层级。", "convertible": true, "correct_option": "7.65×10^-15m", "choice_question": "Calculate the total migration distance S of carbon atoms at 20%, given the transition frequency r=2.1×10^-9/s, transition step length of 2.53×10^-10m, and time of 4h.", "conversion_reason": "The calculation problem has a definite numerical answer, which can be converted into a single-choice question format by presenting the answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "7.65×10^-15m", "B": "3.82×10^-14m", "C": "1.53×10^-10m", "D": "6.12×10^-16m" }, "correct_answer": "A", "explanation": "The correct answer A is calculated using the formula S = √(6Dτ), where D = rλ²/6 (r is transition frequency, λ is step length) and τ is time. Option B incorrectly uses S = √(Dτ) without the factor of 6. Option C is a common mistake from forgetting to square root the expression. Option D results from miscalculating the time conversion from hours to seconds.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1383, "question": "Using dislocation theory, what is the second reason for the work hardening of pure metal single crystals?", "answer": "Dislocation reactions occur, forming immobile dislocations that hinder dislocation motion", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求通过位错理论解释纯金属单晶加工硬化的第二个原因，需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目要求运用位错理论解释纯金属单晶加工硬化的第二个原因，涉及位错反应形成不可动位错并阻碍位错运动的机理。这需要深入理解位错理论，并能将理论知识与实际现象关联起来进行分析和解释，属于复杂分析层次。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生运用位错理论深入分析纯金属单晶加工硬化的第二个原因，涉及位错反应形成不可动位错并阻碍位错运动的复杂机理。这需要考生不仅掌握位错理论的基本概念，还要能够综合运用知识进行机理层面的解释和分析。在选择题型中，这种需要深度理解和复杂推理的题目属于最难的一类。", "convertible": true, "correct_option": "Dislocation reactions occur, forming immobile dislocations that hinder dislocation motion", "choice_question": "Using dislocation theory, what is the second reason for the work hardening of pure metal single crystals?", "conversion_reason": "The answer is a standard concept in dislocation theory, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dislocation reactions occur, forming immobile dislocations that hinder dislocation motion", "B": "Increased dislocation density reduces the mean free path of dislocations", "C": "Lattice distortion caused by solute atoms creates additional barriers", "D": "Cross-slip of screw dislocations becomes energetically unfavorable" }, "correct_answer": "A", "explanation": "The correct answer is A because in pure metal single crystals, dislocation reactions (e.g., Lomer-Cottrell locks) create sessile dislocations that act as strong obstacles. Option B is a primary reason for stage II hardening, not the second reason. Option C incorrectly introduces solute atoms which are absent in pure metals. Option D describes a phenomenon that occurs but isn't the second reason for work hardening - it's a cognitive bias trap using a real but irrelevant dislocation mechanism.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 726, "question": "Non-stoichiometric structural defects are a type of impurity defect caused by doping", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（答案用×表示错误），符合判断题的特征 | 知识层次: 题目考查对非化学计量结构缺陷类型的基本概念记忆和理解，属于基础概念层次 | 难度: 该题目属于基础概念正误判断题，仅需记忆非化学计量缺陷的定义和分类即可作答。在选择题型中，这类题目仅考察最基本的概念记忆能力，无需理解或分析过程，因此属于最低难度等级。", "convertible": true, "correct_option": "×", "choice_question": "Non-stoichiometric structural defects are a type of impurity defect caused by doping", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit ionic bonding as their primary bonding mechanism", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While many ceramics do exhibit ionic bonding, this is not universally true. Some ceramics like silicon carbide (SiC) exhibit primarily covalent bonding. The statement uses an absolute term 'all' which makes it incorrect. This tests the understanding of bonding types in ceramics and the danger of absolute statements in materials science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2042, "question": "Describe the kinetic conditions of crystalline phase transformation", "answer": "The kinetic condition is that the temperature of the liquid at the liquid-solid interface front Ti the melting temperature of glaze formula 2", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种釉配方的熔化温度差异并解释原因，需要文字解释和论述，而不是简单的选择、判断或计算 | 知识层次: 题目要求比较两种釉料配方的熔化温度差异并解释原因，这涉及到对釉料成分及其对熔化温度影响的理解和应用。需要分析不同氧化物（如K2O、Na2O、CaO、PbO、MgO、Al2O3、SiO2）在釉料中的作用及其对熔化温度的影响，属于多步计算和概念关联的综合分析。虽然不涉及复杂的推理或创新设计，但需要一定的综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目要求比较两种釉料配方的熔融温度差异，并解释原因。这涉及到对釉料成分（如K2O、Na2O、CaO、PbO、Al2O3、SiO2等）及其对熔融温度影响的理解。虽然题目提供了具体的配方，但需要考生能够识别关键成分（如PbO的助熔作用、Al2O3和SiO2的提高熔融温度作用）并进行综合分析。此外，还需要进行多步计算和概念关联，但因为是选择题，正确选项已经给出，减少了部分难度。", "convertible": true, "correct_option": "The melting temperature of glaze formula 1 > the melting temperature of glaze formula 2", "choice_question": "From the following two glaze formulas, determine the difference in their melting temperatures. Glaze formula 1: 0.2K2O 0.2Na2O 0.4CaO 0.2PbO 0.3Al2O3 2.1SiO2; Glaze formula 2: 0.2K2O 0.2MgO 0.6CaO 1.1Al2O3 10.0SiO2", "conversion_reason": "The answer is a specific comparison between the two glaze formulas' melting temperatures, which can be directly used as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The melting temperature of glaze formula 1 > the melting temperature of glaze formula 2", "B": "The melting temperature of glaze formula 1 < the melting temperature of glaze formula 2", "C": "Both glazes have identical melting temperatures due to similar alkali content", "D": "Cannot be determined without knowing the exact heating rate" }, "correct_answer": "A", "explanation": "Correct answer is A because glaze formula 1 contains PbO which significantly lowers melting temperature, and has lower Al2O3/SiO2 ratio compared to formula 2. B is wrong but tempting due to higher SiO2 in formula 2 which might seem to increase melting point, but ignores PbO effect. C is wrong by overemphasizing alkali similarity while ignoring other components. D is a common distraction suggesting incomplete information, but relative melting points can be determined from composition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3636, "question": "Would you expect CsBr to have the sodium chloride, zinc blende, fluorite, or cesium chloride structure?", "answer": "CsBr is expected to have the cesium chloride structure.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的四种晶体结构（sodium chloride, zinc blende, fluorite, cesium chloride）中选择CsBr最可能具有的结构类型。 | 知识层次: 题目考查对晶体结构类型的基本记忆和理解，需要根据CsBr的离子半径比和已知的晶体结构类型进行匹配，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然需要记忆CsBr的晶体结构类型，但只需理解离子半径比和配位数等基本原理即可做出正确选择，无需复杂的分析或比较。", "convertible": true, "correct_option": "cesium chloride structure", "choice_question": "Which structure would you expect CsBr to have?", "conversion_reason": "The original question is already in a multiple-choice format, asking to select the expected structure of CsBr from given options. The answer provided specifies the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "cesium chloride structure", "B": "zinc blende structure", "C": "fluorite structure", "D": "sodium chloride structure" }, "correct_answer": "A", "explanation": "The cesium chloride structure is correct due to the large size difference between Cs+ and Br- ions favoring this coordination. Option B (zinc blende) exploits the AI's tendency to default to common semiconductor structures. Option C (fluorite) creates confusion by suggesting a structure often seen with smaller cations. Option D (sodium chloride) is a strong cognitive trap since it's the most common ionic structure, but fails to account for the critical radius ratio in this case.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1278, "question": "What is the growth mode of crystals related to?", "answer": "Interface structure", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释晶体生长模式与什么相关，需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查晶体生长模式与界面结构的关系，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅考察基础概念记忆，涉及晶体生长模式与界面结构关系的简单定义。题目仅要求识别正确选项\"Interface structure\"，无需复杂推理或多概念整合，属于最基本的知识点掌握要求。", "convertible": true, "correct_option": "Interface structure", "choice_question": "What is the growth mode of crystals related to?", "conversion_reason": "The answer is a standard term or concept, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interface structure", "B": "Bulk modulus", "C": "Surface energy anisotropy", "D": "Lattice vibration frequency" }, "correct_answer": "A", "explanation": "The correct answer is A because crystal growth mode is fundamentally determined by the atomic arrangement and bonding at the interface between the crystal and its environment. Option B exploits cognitive bias by using a bulk property unrelated to growth kinetics. Option C is a professional intuition trap, as surface energy affects morphology but not the fundamental growth mode. Option D is a multi-level verification trap, as while phonons influence diffusion, they don't directly determine growth mode classification.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 496, "question": "What processes does aging typically undergo?", "answer": "Aging process: 1) Formation of GP zones. 2) Formation of a series of metastable intermediate phases that maintain coherency or semi-coherency with the parent phase. 3) Formation of stable precipitates. 4) Coarsening and growth of stable precipitates.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释老化过程的不同阶段，答案以文字形式详细描述了老化过程的四个阶段，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查对时效处理过程的基本概念记忆和理解，主要涉及时效过程中各个阶段的描述，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及多个步骤的记忆（GP zones的形成、亚稳中间相的形成、稳定析出相的形成以及其粗化和生长），但这些步骤都是老化过程的典型阶段，属于基础概念的记忆性知识。学生需要能够回忆并识别老化过程的不同阶段，但不需要进行复杂的分析或比较。因此，该题目在选择题型中属于等级2的难度。", "convertible": true, "correct_option": "1) Formation of GP zones. 2) Formation of a series of metastable intermediate phases that maintain coherency or semi-coherency with the parent phase. 3) Formation of stable precipitates. 4) Coarsening and growth of stable precipitates.", "choice_question": "Which of the following sequences correctly describes the typical processes of aging?", "conversion_reason": "The answer is a standard sequence of processes, which can be presented as a correct option among other plausible but incorrect sequences.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1) Formation of GP zones. 2) Formation of metastable θ'' phase. 3) Formation of stable θ phase. 4) Coarsening of θ precipitates", "B": "1) Formation of GP zones. 2) Formation of metastable θ' phase. 3) Formation of stable θ phase. 4) Coarsening of θ precipitates", "C": "1) Formation of GP zones. 2) Formation of metastable θ'' phase. 3) Formation of metastable θ' phase. 4) Formation of stable θ phase", "D": "1) Formation of GP zones. 2) Formation of metastable θ' phase. 3) Formation of metastable θ'' phase. 4) Formation of stable θ phase" }, "correct_answer": "A", "explanation": "The correct sequence for Al-Cu alloys is: 1) GP zones (spherical clusters of Cu atoms), 2) θ'' (coherent disc-shaped precipitates), 3) θ' (semi-coherent precipitates), 4) θ (stable incoherent Al2Cu phase). Option A correctly follows this sequence. Option B incorrectly places θ' before θ''. Option C misses the coarsening stage. Option D reverses the order of θ'' and θ' formation, which is a common mistake due to their similar nomenclature but different formation sequences.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1029, "question": "Dislocation", "answer": "Dislocation: A one-dimensional or linear defect in a crystal, known as a dislocation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Dislocation\"进行文字解释和论述，答案提供了详细的定义和描述，符合简答题的特征 | 知识层次: 题目考查对位错（dislocation）这一基本概念的定义和简单描述，属于基础概念的记忆和理解层面，不涉及应用、分析或综合等高阶认知能力。 | 难度: 在选择题型中，该题目仅要求识别或回忆\"dislocation\"的基本定义，属于最基础的概念记忆层次。正确选项直接给出了明确的定义，无需任何解释、分析或比较步骤，完全符合等级1\"基本定义简答\"的标准。这种题目在选择题中属于最低难度级别，只需对术语有最表层的记忆即可作答。", "convertible": true, "correct_option": "A one-dimensional or linear defect in a crystal, known as a dislocation.", "choice_question": "Which of the following best describes a dislocation?", "conversion_reason": "The answer is a standard definition of a term, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A one-dimensional or linear defect in a crystal, known as a dislocation", "B": "A two-dimensional planar defect where the crystal lattice abruptly changes orientation", "C": "A point defect caused by the absence of an atom in the crystal lattice", "D": "A three-dimensional region of disorder within an otherwise perfect crystal" }, "correct_answer": "A", "explanation": "The correct answer is A because a dislocation is specifically defined as a one-dimensional or linear defect in a crystal. Option B describes a grain boundary, which is a two-dimensional defect. Option C describes a vacancy, which is a point defect. Option D describes an amorphous region, which is not a dislocation. The difficulty lies in the subtle distinctions between different types of crystal defects, which can be easily confused without precise knowledge of their dimensional characteristics.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4414, "question": "Give the approximate minimum temperature at which it is possible to austenitize a 0.20 wt% C iron-carbon alloy during a normalizing heat treatment.", "answer": "At least 905°C (1660°F)", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求给出一个具体的温度值作为答案，而不是从选项中选择或进行判断。虽然答案是一个数值，但解答过程需要基于材料科学知识（如铁碳相图）进行解释和推导，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目需要应用铁碳相图的基本知识来确定奥氏体化温度，属于直接套用相图信息的简单应用，不需要多步计算或复杂分析。 | 难度: 在选择题中属于简单应用难度，仅需直接套用铁碳相图中的基本知识（A3线）即可得出答案，无需复杂计算或深入分析。", "convertible": true, "correct_option": "At least 905°C (1660°F)", "choice_question": "What is the approximate minimum temperature at which it is possible to austenitize a 0.20 wt% C iron-carbon alloy during a normalizing heat treatment?", "conversion_reason": "The answer is a specific temperature value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "At least 905°C (1660°F)", "B": "At least 727°C (1340°F)", "C": "At least 850°C (1560°F)", "D": "At least 723°C (1333°F)" }, "correct_answer": "A", "explanation": "The correct answer is A because the minimum austenitizing temperature for a 0.20 wt% C iron-carbon alloy is approximately 905°C, which is above the A3 line on the phase diagram. Option B (727°C) is the eutectoid temperature (A1 line), which is a common confusion point. Option C (850°C) is a typical austenitizing temperature used in practice but not the theoretical minimum. Option D (723°C) is a red herring using a slightly modified eutectoid temperature value to catch those relying on memory without consulting the phase diagram.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2674, "question": "According to X-ray diffraction measurements, at 912°C, the lattice parameter a of α-Fe is 0.2892 nm, and that of γ-Fe is 0.3633 nm. Calculate the volume expansion when γ-Fe transforms into α-Fe.", "answer": "fcc: r = sqrt(2)/4 * a = sqrt(2)/4 * 0.3633 = 0.1284 nm; bcc: r = sqrt(3)/4 * a = sqrt(3)/4 * 0.2892 = 0.1251 nm; ΔV = (1/2 * (0.2892)^3 - 1/4 * (0.3633)^3) / (1/4 * (0.3633)^3) = 0.87%", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及晶格参数和体积变化的计算，答案以数值结果呈现。 | 知识层次: 题目需要进行多步计算，包括晶格参数转换、体积计算和体积变化率的计算，涉及fcc和bcc晶体结构的几何关系，需要综合应用材料科学中的晶体学知识。虽然不涉及复杂的机理分析或创新设计，但计算过程需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解晶体结构（fcc和bcc）的几何关系，掌握晶格参数与原子半径的换算公式，并进行多步计算（包括立方运算和百分比变化）。虽然题目提供了关键参数，但解题过程涉及多个概念的关联和综合计算，属于典型的综合性计算问题。", "convertible": true, "correct_option": "0.87%", "choice_question": "According to X-ray diffraction measurements, at 912°C, the lattice parameter a of α-Fe is 0.2892 nm, and that of γ-Fe is 0.3633 nm. What is the volume expansion when γ-Fe transforms into α-Fe?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.87%", "B": "1.24%", "C": "-2.15%", "D": "3.68%" }, "correct_answer": "A", "explanation": "The correct answer is A (0.87%) because the volume change is calculated by comparing the unit cell volumes of γ-Fe (FCC) and α-Fe (BCC). The FCC unit cell contains 4 atoms with volume a³, while BCC contains 2 atoms with volume a³. After normalizing for equal atom numbers, the volume change is 0.87%. Option B (1.24%) is a common error from forgetting to normalize for atom count. Option C (-2.15%) incorrectly assumes contraction instead of expansion. Option D (3.68%) results from miscalculating the coordination number effect.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3759, "question": "Calculate the diameter of the cylindrical riser required to prevent shrinkage in a 4 in. × 10 in. × 20 in. casting if the H / D of the riser is 1.5.", "answer": "the diameter of the riser d ≥ 6.67 in.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算圆柱形冒口的直径），并给出了具体的公式应用（H/D比例），最终答案是一个具体的数值结果。 | 知识层次: 题目需要进行多步计算，涉及铸造工艺中缩孔预防的圆柱形冒口设计，需要应用H/D比和体积关系等概念进行综合分析，但不需要复杂的机理分析或创新设计。 | 难度: 在选择题中属于中等偏上难度，需要理解铸造收缩原理、冒口设计公式（H/D比）并进行多步计算。题目要求将几何参数转换为数学关系式，并综合判断最小直径值，涉及中等应用层次的知识关联和计算能力。虽然选项已给出正确数值，但解题过程需要综合分析多个变量（铸件尺寸、H/D比、体积补偿关系），在选择题型中属于需要较强计算能力的题目。", "convertible": true, "correct_option": "d ≥ 6.67 in.", "choice_question": "What is the diameter of the cylindrical riser required to prevent shrinkage in a 4 in. × 10 in. × 20 in. casting if the H / D of the riser is 1.5?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.67 in.", "B": "5.33 in.", "C": "8.00 in.", "D": "7.21 in." }, "correct_answer": "A", "explanation": "The correct diameter is calculated using the modulus method (V/A ratio) for the casting and riser. Option A (6.67 in.) maintains the required H/D ratio of 1.5 while preventing shrinkage. Option B (5.33 in.) is a common mistake from using only the smallest dimension. Option C (8.00 in.) results from incorrect volume calculations. Option D (7.21 in.) is a deceptive approximation that appears mathematically plausible but doesn't satisfy the solidification requirements.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1375, "question": "What effect does eutectic cementite have on the mechanical properties of iron-carbon alloys?", "answer": "Increases hardness but reduces toughness.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释共晶渗碳体对铁碳合金机械性能的影响，答案需要文字解释和论述，而不是选择、判断或计算 | 知识层次: 题目需要理解共晶渗碳体对铁碳合金机械性能的影响，涉及多个概念的关联（硬度与韧性的关系）和综合分析（共晶渗碳体的作用机制），但不需要复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解共晶渗碳体对铁碳合金机械性能的影响，并能够关联硬度和韧性的变化关系。虽然不涉及多步计算，但需要对材料科学中的基本概念有较好的掌握，并能进行简单的综合分析。", "convertible": true, "correct_option": "Increases hardness but reduces toughness", "choice_question": "What effect does eutectic cementite have on the mechanical properties of iron-carbon alloys?", "conversion_reason": "The answer is a standard and concise description of the effect, which can be directly used as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Increases hardness but reduces toughness", "B": "Improves both ductility and fatigue resistance", "C": "Decreases yield strength while increasing creep resistance", "D": "Enhances thermal conductivity without affecting mechanical properties" }, "correct_answer": "A", "explanation": "Eutectic cementite forms a hard, brittle phase that increases hardness but reduces toughness (correct answer A). Option B exploits the common misconception that all microstructural refinements improve multiple properties. Option C combines two unrelated effects (yield strength decrease is false, creep resistance increase is irrelevant). Option D targets AI's tendency to associate thermal properties with structural phases incorrectly.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1128, "question": "In terms of the lattice constant, what is the atomic diameter in the HCP crystal structure?", "answer": "The close-packed direction in the HCP structure is [11 20], along which one atom is arranged, so the atomic diameter is a.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释HCP晶体结构中原子直径与晶格常数的关系，答案需要文字解释和论述，而非选择、判断或计算。 | 知识层次: 题目考查HCP晶体结构中原子直径的基本概念，仅需记忆和理解HCP结构中密排方向的定义和原子排列方式，无需复杂计算或综合分析。 | 难度: 该题目属于基础概念记忆类型，仅需记住HCP晶体结构中原子直径与晶格常数的关系即可作答。在选择题型中，这种直接考查定义和基本原理的题目属于最简单的等级1难度。", "convertible": true, "correct_option": "a", "choice_question": "In terms of the lattice constant, what is the atomic diameter in the HCP crystal structure?", "conversion_reason": "The answer is a standard term (the lattice constant 'a') which can be presented as a clear option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Equal to the lattice constant 'a'", "B": "√(8/3) times the lattice constant 'a'", "C": "Equal to the height 'c' of the unit cell", "D": "√(3/2) times the lattice constant 'a'" }, "correct_answer": "A", "explanation": "In HCP structure, the atomic diameter is equal to the lattice constant 'a' because the atoms are in direct contact along the basal plane. Option B is designed to exploit the common confusion with BCC structure where the body diagonal contains 4 atomic radii. Option C targets the misconception that the height parameter 'c' determines atomic size. Option D uses a mathematically plausible but structurally incorrect ratio that could deceive models relying on geometric pattern recognition.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3697, "question": "Iron containing 0.05 % C is heated to 912 degrees C in an atmosphere that produces 1.20 % C at the surface and is held for 24 h. Calculate the carbon content at 0.05 cm beneath the surface if the iron is FCC.", "answer": "For FCC iron, the carbon content at 0.05 cm beneath the surface is 0.95 % C.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算碳含量），并涉及公式应用（FCC结构下的扩散计算），答案以具体数值形式给出。 | 知识层次: 题目需要进行多步计算，包括理解FCC结构对碳扩散的影响、应用扩散方程计算碳含量变化，并综合分析时间和距离对碳浓度分布的影响。这需要将多个概念关联起来并进行中等复杂度的计算。 | 难度: 在选择题中属于中等难度，需要理解扩散原理、相图知识，并进行多步计算和综合分析。虽然题目提供了正确选项，但解题过程涉及菲克第二定律的应用、边界条件设定以及浓度梯度计算，属于综合性计算问题。", "convertible": true, "correct_option": "0.95 % C", "choice_question": "Iron containing 0.05 % C is heated to 912 degrees C in an atmosphere that produces 1.20 % C at the surface and is held for 24 h. The carbon content at 0.05 cm beneath the surface if the iron is FCC is:", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.95 % C", "B": "1.12 % C", "C": "0.72 % C", "D": "0.05 % C" }, "correct_answer": "A", "explanation": "正确答案A基于Fick第二定律的正确应用，考虑了FCC铁在912°C下的扩散系数和24小时的处理时间。干扰项B利用了'表面浓度会线性衰减'的错误直觉；干扰项C基于对奥氏体最大溶解度的错误联想；干扰项D利用了'初始浓度不变'的简单化思维陷阱。这些干扰项都针对AI模型在处理扩散问题时的常见计算和概念错误。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2002, "question": "Is the statement 'Small-angle grain boundaries are all formed by edge dislocations arranged into walls' correct?", "answer": "No. Twist boundaries are formed by crossed screw dislocations of the same sign.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断一个陈述的正确性（'Small-angle grain boundaries are all formed by edge dislocations arranged into walls'），答案直接给出了该陈述是错误的（No）并提供了正确的解释。这符合判断题的特征，即判断陈述的对错并简要说明原因。 | 知识层次: 题目考查对晶界类型和位错排列的基本概念的记忆和理解，属于基础概念记忆范畴。 | 难度: 在选择题型中，该题目属于概念理解的对错判断难度。题目考察学生对小角度晶界形成机制的理解，需要区分边缘位错和螺旋位错在晶界形成中的作用。虽然涉及基础概念记忆，但需要将定义和分类知识应用到具体情境中进行判断，比单纯的正误判断稍复杂，但不需要多概念比较分析。", "convertible": true, "correct_option": "No. Twist boundaries are formed by crossed screw dislocations of the same sign.", "choice_question": "Is the statement 'Small-angle grain boundaries are all formed by edge dislocations arranged into walls' correct?", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "Small-angle grain boundaries are all formed by edge dislocations arranged into walls", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While some small-angle grain boundaries (like tilt boundaries) are formed by edge dislocations arranged into walls, this is not universally true. Twist boundaries, another type of small-angle grain boundary, are formed by crossed screw dislocations of the same sign. The statement's use of 'all' makes it incorrect as it doesn't account for this important exception in dislocation arrangements.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3016, "question": "The usage state of plastic is (). A. Crystalline state B. Glassy state C. High elastic state D. Viscous flow state", "answer": "B", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从四个选项中选择塑料使用状态的正确答案 | 知识层次: 题目考查塑料使用状态的基本概念记忆，属于对材料科学基础知识的直接考察，无需复杂推理或综合分析。 | 难度: 在选择题型中，该题目属于基础概念记忆，仅需识别塑料的使用状态为玻璃态（Glassy state），无需复杂辨析或深度理解。题目直接考察定义性知识，属于简单概念识别。", "convertible": true, "correct_option": "B. Glassy state", "choice_question": "The usage state of plastic is ().", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The elastic modulus of a polymer is primarily determined by its degree of crystallinity", "B": "The glass transition temperature (Tg) of an amorphous polymer is the temperature at which it becomes completely liquid", "C": "The viscoelastic behavior of polymers is best described by Hooke's law alone", "D": "The stress-strain curve of a ductile polymer shows no yield point under standard testing conditions" }, "correct_answer": "A", "explanation": "Correct answer A is counterintuitive because while crystallinity affects modulus, the primary determinant is actually chain mobility and intermolecular forces. Option B exploits the common misconception that Tg represents complete liquefaction rather than just the onset of segmental motion. Option C targets the oversimplification of viscoelastic behavior which requires time-dependent models. Option D uses the deceptive absence of yield point which actually exists in most ductile polymers.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 8, "question": "What are the characteristics of metallic bonds?", "answer": "Metallic bonds are non-directional and non-saturated covalent bonds, where the binding force is the electrostatic Coulomb force between ions.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释金属键的特性，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查金属键的基本特性，属于基础概念的记忆和理解，不涉及复杂分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生理解并记忆金属键的基本特性（非方向性和非饱和性共价键），以及其作用力本质（离子间的静电库仑力）。虽然涉及多个概念，但都属于基础概念记忆层次，不需要复杂的分析或比较。因此，难度等级为2。", "convertible": true, "correct_option": "Metallic bonds are non-directional and non-saturated covalent bonds, where the binding force is the electrostatic Coulomb force between ions.", "choice_question": "Which of the following correctly describes the characteristics of metallic bonds?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by rephrasing the question to ask for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Metallic bonds are non-directional and non-saturated covalent bonds, where the binding force is the electrostatic Coulomb force between ions", "B": "Metallic bonds exhibit strong directional characteristics similar to covalent bonds, with localized electron pairs", "C": "The strength of metallic bonds is primarily determined by the number of valence electrons, similar to ionic bonding", "D": "Metallic bonding involves electron transfer between atoms, creating positively charged metal ions embedded in a sea of electrons" }, "correct_answer": "A", "explanation": "The correct answer A accurately describes metallic bonds as non-directional and non-saturated, with the binding force being the Coulombic attraction between delocalized electrons and positive ions. Option B incorrectly attributes directional characteristics to metallic bonds, which is a common confusion with covalent bonds. Option C wrongly suggests the bond strength depends solely on valence electron count, ignoring the role of electron delocalization. Option D describes the electron sea model but inaccurately implies electron transfer occurs, which is a characteristic of ionic rather than metallic bonding.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3675, "question": "For an ASTM grain size number of 8, calculate the number of grains per square inch at a magnification of 100.", "answer": "128 grains/in.^2", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算每平方英寸的晶粒数量），并应用ASTM晶粒尺寸公式，答案是一个具体的数值结果。 | 知识层次: 题目涉及ASTM晶粒度标准的基本公式应用，计算过程直接套用公式即可完成，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目直接要求应用ASTM晶粒度计算公式，仅需简单代入数值即可得出结果，无需复杂推理或多步骤计算。正确选项直接对应公式计算结果，属于最基础的应用层次。", "convertible": true, "correct_option": "128 grains/in.^2", "choice_question": "For an ASTM grain size number of 8, the number of grains per square inch at a magnification of 100 is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "128 grains/in.^2", "B": "256 grains/in.^2", "C": "64 grains/in.^2", "D": "512 grains/in.^2" }, "correct_answer": "A", "explanation": "The correct answer is A (128 grains/in.^2) based on the ASTM grain size formula N=2^(n-1) where n=8. Option B (256) is a cognitive bias trap by doubling the correct value, exploiting the common mistake of not subtracting 1 in the exponent. Option C (64) is a professional intuition trap using n-2 instead of n-1 in the exponent. Option D (512) is a multi-level verification trap by incorrectly using n+1 in the exponent, which might seem plausible for higher magnification scales.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4621, "question": "Briefly describe the phenomenon of dispersion in a transparent medium.", "answer": "Dispersion in a transparent medium is the phenomenon wherein the index of refraction varies slightly with the wavelength of the electromagnetic radiation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求简要描述透明介质中的色散现象，答案是一个文字解释和论述的形式，符合简答题的特征 | 知识层次: 题目考查对色散现象这一基本概念的定义和简单理解，属于基础概念记忆范畴 | 难度: 在选择题型中，该题目仅要求考生回忆并识别透明介质中色散现象的基本定义。题目涉及的知识点属于基础概念记忆层次，解题步骤简单，只需选择与定义相符的正确选项即可，无需进行复杂的概念比较或分析。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "Dispersion in a transparent medium is the phenomenon wherein the index of refraction varies slightly with the wavelength of the electromagnetic radiation.", "choice_question": "Which of the following best describes the phenomenon of dispersion in a transparent medium?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by providing the correct description among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Dispersion in a transparent medium is the phenomenon wherein the index of refraction varies slightly with the wavelength of the electromagnetic radiation.", "B": "Dispersion in a transparent medium refers to the scattering of light due to microscopic inhomogeneities in the material's density.", "C": "Dispersion describes the uniform speed of electromagnetic waves regardless of their wavelength when passing through a transparent medium.", "D": "Dispersion is the phenomenon where all wavelengths of light experience identical refractive indices in a transparent medium." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines dispersion as wavelength-dependent refractive index variation. Option B incorrectly describes scattering rather than dispersion. Option C reverses the fundamental concept by claiming uniform speed. Option D contradicts dispersion by suggesting identical refractive indices. These distractors exploit common misconceptions about light-matter interactions, scattering phenomena, and the inverse relationship between wavelength and refractive index.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3761, "question": "Calculate the volume of the cylindrical riser required to prevent shrinkage in a 4 in. × 10 in. × 20 in. casting if the H / D of the riser is 1.5.", "answer": "the volume of the riser v ≥ 349 in.^3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算（计算圆柱形冒口的体积），并给出了具体的参数（H/D比例和铸件尺寸），答案也是一个具体的数值结果（349 in.^3），符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括理解圆柱形冒口的体积计算、H/D比的应用以及防止收缩的条件分析。虽然计算本身不复杂，但需要综合运用多个概念和公式，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解圆柱形冒口的设计原理（H/D比）、体积计算公式，并能够将铸造收缩预防需求转化为具体计算步骤。题目要求进行多步计算（确定冒口直径与高度的关系、计算体积），并需要将理论知识与工程实践（防缩需求）相结合，但作为选择题型，正确答案的选项降低了部分推导难度。", "convertible": true, "correct_option": "v ≥ 349 in.^3", "choice_question": "What is the required volume of the cylindrical riser to prevent shrinkage in a 4 in. × 10 in. × 20 in. casting if the H / D of the riser is 1.5?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "v ≥ 349 in.^3", "B": "v ≥ 274 in.^3", "C": "v ≥ 412 in.^3", "D": "v ≥ 187 in.^3" }, "correct_answer": "A", "explanation": "The correct answer is A because it properly accounts for both the casting's volume (800 in.^3) and the required riser volume based on the Chvorinov's rule with H/D=1.5. Option B underestimates by using only the casting's surface area, a common error when misapplying solidification time calculations. Option C overestimates by incorrectly including the riser's own volume in the calculation, a frequent mistake in iterative volume determinations. Option D represents a dangerous underestimation that might result from confusing diameter with radius in the riser volume calculation, a typical unit conversion error.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4617, "question": "What are the characteristics of translucent materials in terms of their appearance and light transmittance?", "answer": "Light is transmitted diffusely through translucent materials (there is some internal light scattering). Objects are not clearly distinguishable when viewed through a translucent material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释和描述半透明材料的外观和光透射特性，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对半透明材料基本特性的记忆和理解，包括光传输方式和视觉效果的描述，属于基础概念层面的知识。 | 难度: 在选择题型中，该题目属于中等难度。虽然考察的是基础概念记忆（translucent materials的定义和特性），但需要考生准确理解并描述半透明材料的光学特性（漫透射和物体辨识度）。这比单纯识别定义（等级1）要求更高，但尚未达到需要分析复杂概念体系（等级3）的程度。正确选项完整描述了半透明材料的两个关键特征，符合\"概念解释和描述\"的难度标准。", "convertible": true, "correct_option": "Light is transmitted diffusely through translucent materials (there is some internal light scattering). Objects are not clearly distinguishable when viewed through a translucent material.", "choice_question": "Which of the following best describes the characteristics of translucent materials in terms of their appearance and light transmittance?", "conversion_reason": "The answer is a standard description of the characteristics of translucent materials, which can be used as the correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Light is transmitted diffusely through translucent materials (there is some internal light scattering). Objects are not clearly distinguishable when viewed through a translucent material.", "B": "Translucent materials exhibit specular transmission with minimal scattering, allowing clear image formation similar to transparent materials but with reduced intensity.", "C": "The degree of translucency is primarily determined by the material's bandgap energy, with wider bandgaps resulting in higher translucency.", "D": "Translucent materials completely absorb all visible light wavelengths above their absorption edge, only transmitting wavelengths below this threshold." }, "correct_answer": "A", "explanation": "Correct answer A accurately describes the fundamental optical behavior of translucent materials where light undergoes diffuse transmission due to internal scattering. Option B incorrectly attributes specular transmission to translucent materials - this is characteristic of transparent materials. Option C uses a plausible-sounding but incorrect materials science concept (bandgap energy primarily determines transparency in semiconductors, not translucency in general materials). Option D describes an absorption-edge phenomenon that's irrelevant to typical translucent material behavior, creating a sophisticated but misleading distraction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1652, "question": "Covalent bond", "answer": "A valence bond formed between adjacent atoms due to the sharing of electron pairs, characterized by saturation and directionality", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对\"Covalent bond\"进行文字解释和论述，答案提供了详细的定义和特征描述，符合简答题的特点 | 知识层次: 题目考查共价键的基本定义和特征，属于基础概念的记忆和理解 | 难度: 在选择题型中，该题目仅要求考生记忆并识别共价键的基本定义和特征（电子对共享、饱和性和方向性），属于最基础的概念记忆层次，无需解释或分析复杂概念体系。", "convertible": true, "correct_option": "A valence bond formed between adjacent atoms due to the sharing of electron pairs, characterized by saturation and directionality", "choice_question": "Which of the following best describes a covalent bond?", "conversion_reason": "The answer is a standard definition of a covalent bond, which can be presented as one of several options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A valence bond formed between adjacent atoms due to the sharing of electron pairs, characterized by saturation and directionality", "B": "An electrostatic interaction between fully ionized atoms with opposite charges", "C": "A metallic bond where electrons are delocalized across the entire crystal lattice", "D": "A secondary bond caused by instantaneous dipole interactions between neutral atoms" }, "correct_answer": "A", "explanation": "The correct answer A precisely defines covalent bonding with key characteristics. Option B describes ionic bonding, exploiting the common confusion between primary bond types. Option C targets metallic bonding misconceptions, using the 'electron sharing' aspect as a trap. Option D leverages van der Waals bonds which are often mistakenly considered primary bonds like covalent bonds. Advanced AI might confuse these due to surface-level similarities in 'electron interactions' terminology.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4674, "question": "To what equation does the expression for interplanar spacing (d_{\text {hkl }}) reduce for crystals having tetragonal symmetry, given that a, b and c are the lattice parameters?", "answer": "For crystals having tetragonal symmetry, a=b \neq c. Replacing b with a in the given equation leads to (\frac{1}{d_{h k l}^{2}}=\frac{h^{2}}{a^{2}}+\frac{k^{2}}{a^{2}}+\frac{l^{2}}{c^{2}} = \frac{h^{2}+k^{2}}{a^{2}}+\frac{l^{2}}{c^{2}}).", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释并推导出特定晶体对称性下的晶面间距表达式，答案提供了详细的推导过程和最终公式，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目要求将四方晶系的对称性条件（a=b≠c）代入晶面间距公式进行简化，属于基本公式的直接应用，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需直接套用基本公式并进行简单的代数替换（将b替换为a）。解题步骤简单明确，无需复杂推导或深入理解多个概念，符合等级2的简单应用过程描述标准。", "convertible": true, "correct_option": "For crystals having tetragonal symmetry, a=b ≠ c. Replacing b with a in the given equation leads to (rac{1}{d_{h k l}^{2}}=rac{h^{2}}{a^{2}}+rac{k^{2}}{a^{2}}+rac{l^{2}}{c^{2}} = rac{h^{2}+k^{2}}{a^{2}}+rac{l^{2}}{c^{2}}).", "choice_question": "To what equation does the expression for interplanar spacing (d_{ ext {hkl }}) reduce for crystals having tetragonal symmetry, given that a, b and c are the lattice parameters?", "conversion_reason": "The answer is a standard equation derived from the given conditions, making it suitable for conversion to a multiple-choice format where the correct option is the derived equation.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1/d² = (h² + k²)/a² + l²/c²", "B": "1/d² = (h² + k² + l²)/a²", "C": "1/d² = (h² + k²)/c² + l²/a²", "D": "1/d² = (h² + k²)/a² + (l²)/b²" }, "correct_answer": "A", "explanation": "The correct answer A accounts for the tetragonal symmetry where a=b≠c. Option B incorrectly assumes cubic symmetry. Option C reverses the a and c terms, exploiting common parameter confusion. Option D maintains the b parameter which doesn't exist in tetragonal systems, targeting failure to recognize symmetry reduction.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2268, "question": "Why do transition phases appear during the precipitation process?", "answer": "Transition phases appear during the precipitation process because the system requires a series of intermediate transition phases to gradually reduce free energy during the transformation from a supersaturated solid solution to the equilibrium phase. These transition phases, with their crystal structures and compositions intermediate between GP zones and the equilibrium phase, can reduce nucleation work and strain energy, making the phase transformation process easier to proceed.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求解释过渡相在析出过程中出现的原因，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释过渡相在析出过程中出现的原因，涉及自由能降低、中间过渡相的作用、晶体结构和成分的中间性、形核功和应变能的减少等多个方面的综合分析。需要深入理解相变机理，并能将这些概念关联起来进行推理分析，属于复杂分析层次。 | 难度: 在选择题型内，该题目属于最高难度等级。题目要求深入理解相变过程中的自由能变化、过渡相的作用机理等复杂概念，并能综合运用这些知识解释现象。正确选项涉及多个专业概念（如GP区、应变能、形核功等）的关联分析，需要考生具备将理论知识转化为机理解释的能力，这远超出简单记忆或基础理解的范畴。在选择题型中，此类需要综合推理和机理深度分析的题目属于最复杂的类型。", "convertible": true, "correct_option": "Transition phases appear during the precipitation process because the system requires a series of intermediate transition phases to gradually reduce free energy during the transformation from a supersaturated solid solution to the equilibrium phase. These transition phases, with their crystal structures and compositions intermediate between GP zones and the equilibrium phase, can reduce nucleation work and strain energy, making the phase transformation process easier to proceed.", "choice_question": "Why do transition phases appear during the precipitation process?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "To minimize interfacial energy by forming coherent interfaces with the matrix", "B": "Because they have lower activation energy for nucleation than the equilibrium phase", "C": "Due to the need to maintain lattice continuity during phase transformation", "D": "As a result of kinetic limitations preventing direct formation of the equilibrium phase" }, "correct_answer": "B", "explanation": "The correct answer is B because transition phases appear primarily due to their lower nucleation barriers compared to the equilibrium phase, allowing the system to reduce free energy through intermediate steps. Option A is a cognitive bias trap - while interfacial energy is important, it's not the primary driver for transition phase formation. Option C exploits professional intuition about lattice continuity, which is a secondary consideration. Option D is a multi-level verification trap that seems plausible but incorrectly attributes the phenomenon to kinetic limitations rather than thermodynamic driving forces.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3197, "question": "Given: The volumetric latent heat of fusion for aluminum Lm=1.836×10^9 J/m^3, melting point Tm=993K, undercooling ΔT=19℃. Calculate the change in volumetric free energy ΔGV during the transformation from liquid to solid.", "answer": "ΔGV = (-Lm ΔT) / Tm = (-1.836 × 10^9 × 19) / 993 = -3.51 × 10^7 J/m^3", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，答案是通过具体计算得出的数值结果。 | 知识层次: 题目要求直接套用给定的公式进行数值计算，涉及基本的公式应用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求直接套用给定的公式 ΔGV = (-Lm ΔT) / Tm，并进行简单的数值代入和计算。不需要理解多个概念或进行复杂的分析，仅需基本的代数运算能力即可得出正确答案。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "-3.51 × 10^7 J/m^3", "choice_question": "Given: The volumetric latent heat of fusion for aluminum Lm=1.836×10^9 J/m^3, melting point Tm=993K, undercooling ΔT=19℃. What is the change in volumetric free energy ΔGV during the transformation from liquid to solid?", "conversion_reason": "The calculation question has a specific numerical answer, making it suitable for conversion into a multiple-choice format where the correct option is the calculated value.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "-3.51 × 10^7 J/m^3", "B": "-1.836 × 10^9 J/m^3", "C": "-6.72 × 10^7 J/m^3", "D": "-1.12 × 10^8 J/m^3" }, "correct_answer": "A", "explanation": "The correct answer is calculated using ΔGV = -Lm × ΔT/Tm. Option B directly uses the latent heat value without considering the undercooling ratio, exploiting the cognitive bias of using the most prominent number. Option C results from incorrectly using the Celsius melting point (660°C) instead of Kelvin in the denominator. Option D comes from a common error in unit conversion where the undercooling is mistakenly treated in Kelvin instead of Celsius.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4010, "question": "Seawater, which covers the majority of the earth, is composed primarily of molecules of H_{2} \\mathrm{O} and equal numbers of \\mathrm{Na}^{+}ions and \\mathrm{Cl}^{-}ions. Suppose we have a thoroughly mixed solution (containing these species only) at 25^{\\circ} C. How many components and how many phases are in such a system?\n(a) 1 component, 1 phase\n(b) 1 component, 2 phase\n(c) 1 component, 3 phase\n(d) 1 component, 4 phase\n(e) 2 component, 1 phase\n(f) 2 component, 2 phase\n(g) 2 component, 3 phase\n(h) 2 component, 4 phase\n(i) 3 component, 1 phase\n(j) 3 component, 2 phase\n(k) 3 component, 3 phase(l) 3 component, 4 phase\n(m) 4 component, 1 phase\n(n) 4 component, 2 phase\n(o) 4 component, 3 phase\n(p) 4 component, 4 phase", "answer": "(e) 2 component, 1 phase", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从多个选项中选择正确答案，且提供了多个选项供选择 | 知识层次: 题目考查对组分和相这两个基本概念的记忆和理解，不需要复杂的计算或分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及基础概念记忆（如组分和相的定义），但需要考生理解并区分不同化学物种（H2O、Na+、Cl-）在系统中的分类方式。解题步骤相对直接，但需要明确区分独立组分数和相数的概念，并进行简单辨析。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "(e) 2 component, 1 phase", "choice_question": "Seawater, which covers the majority of the earth, is composed primarily of molecules of H_{2} \\mathrm{O} and equal numbers of \\mathrm{Na}^{+}ions and \\mathrm{Cl}^{-}ions. Suppose we have a thoroughly mixed solution (containing these species only) at 25^{\\circ} C. How many components and how many phases are in such a system?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it convertible to a single-choice question format without any modifications needed.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1 component, 1 phase", "B": "1 component, 2 phase", "C": "2 component, 1 phase", "D": "3 component, 1 phase" }, "correct_answer": "C", "explanation": "The correct answer is C because in this system, there are two components (H2O and NaCl, since Na+ and Cl- ions are derived from the same salt) and one phase (a homogeneous aqueous solution). Option A is incorrect as it underestimates the number of components by treating the entire system as a single component. Option B introduces an incorrect phase separation that doesn't exist in this thoroughly mixed solution. Option D overcounts components by treating Na+ and Cl- as separate components rather than derived from the same salt.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4572, "question": "At room temperature the electrical conductivity and the electron mobility for copper are 6.0 x 10^7 (Ω·m)^-1 and 0.0030 m^2/V·s, respectively. Compute the number of free electrons per cubic meter for copper at room temperature.", "answer": "the number of free electrons per cubic meter for copper at room temperature is 1.25 x 10^29 m^-3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过给定的电导率和电子迁移率数据，应用相关公式计算铜在室温下的自由电子数密度。解答过程涉及数值计算和公式应用，答案是一个具体的数值结果。 | 知识层次: 题目需要应用基本的电导率公式（σ = n e μ）进行简单计算，属于直接套用公式的范畴，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需要直接应用单一公式（电导率与电子迁移率和自由电子浓度的关系公式）进行计算，无需复杂的推导或多步骤组合。题目提供了所有必要的数据，且计算过程简单直接，属于单一公式直接计算的难度等级。", "convertible": true, "correct_option": "1.25 x 10^29 m^-3", "choice_question": "At room temperature the electrical conductivity and the electron mobility for copper are 6.0 x 10^7 (Ω·m)^-1 and 0.0030 m^2/V·s, respectively. The number of free electrons per cubic meter for copper at room temperature is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.25 x 10^29 m^-3", "B": "6.25 x 10^28 m^-3", "C": "2.50 x 10^29 m^-3", "D": "3.13 x 10^28 m^-3" }, "correct_answer": "A", "explanation": "正确答案A是通过σ = n·e·μ公式计算得出，其中σ=6.0x10^7 (Ω·m)^-1，μ=0.0030 m^2/V·s，e=1.6x10^-19 C。干扰项B是错误地将σ除以2倍e·μ的结果，利用了常见计算错误。干扰项C是错误地将σ直接除以e而不考虑μ，利用了单位混淆。干扰项D是错误地将μ值作为分母进行计算，利用了参数位置混淆。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 896, "question": "Term explanation: deformation texture", "answer": "The phenomenon of crystallographic orientation preference occurring during polycrystalline deformation is called deformation texture.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对术语进行解释，答案是一段文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对\"deformation texture\"这一基本概念的定义和记忆，属于材料科学中基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别\"deformation texture\"的基本定义，属于最基础的概念记忆层次。题目直接给出了术语的明确定义，不需要进行任何解释、比较或分析，完全符合等级1\"基本定义简答\"的标准。这种题目在选择题中属于最简单的一类，只需考生对专业术语有最基本的记忆即可作答。", "convertible": true, "correct_option": "The phenomenon of crystallographic orientation preference occurring during polycrystalline deformation is called deformation texture.", "choice_question": "Which of the following best defines deformation texture?", "conversion_reason": "The answer is a standard definition of a term, which can be converted into a multiple-choice question format by asking for the correct definition among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The phenomenon of crystallographic orientation preference occurring during polycrystalline deformation", "B": "The residual stress distribution pattern formed after plastic deformation", "C": "The anisotropic mechanical properties resulting from cold working processes", "D": "The grain boundary misorientation angle distribution in deformed materials" }, "correct_answer": "A", "explanation": "Option A is correct as it precisely defines deformation texture as the preferred crystallographic orientation developed during deformation. Option B exploits confusion with residual stress measurement. Option C uses a related but incorrect concept of mechanical anisotropy. Option D targets confusion with grain boundary characterization techniques rather than texture formation.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 181, "question": "What is the additional pressure on a curved surface? How is its sign determined?", "answer": "Due to the existence of surface tension, an additional pressure is generated on a curved surface. If the pressure on a flat surface is P0 and the pressure difference generated by the curved surface is △P, then the total pressure is P=P0+△P. The sign of the additional pressure depends on the curvature of the surface: positive for convex surfaces and negative for concave surfaces.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释什么是附加压力以及如何确定其符号，答案提供了详细的文字解释和论述，没有涉及计算或选择选项。 | 知识层次: 题目考查对表面张力引起的附加压力及其符号确定的基本概念的理解和记忆，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目属于中等难度。题目要求考生理解表面张力在曲面上产生的附加压力，并能够根据曲面的凸凹性判断附加压力的符号。虽然涉及基础概念的记忆，但需要考生对概念有一定的理解和应用能力，而不仅仅是简单的定义记忆。因此，难度等级为2。", "convertible": true, "correct_option": "Due to the existence of surface tension, an additional pressure is generated on a curved surface. If the pressure on a flat surface is P0 and the pressure difference generated by the curved surface is △P, then the total pressure is P=P0+△P. The sign of the additional pressure depends on the curvature of the surface: positive for convex surfaces and negative for concave surfaces.", "choice_question": "What is the additional pressure on a curved surface and how is its sign determined?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice format. The question can be rephrased to fit a multiple-choice structure by focusing on the key concept being asked.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The additional pressure is determined by surface tension and curvature, with positive sign for convex surfaces and negative for concave surfaces", "B": "The additional pressure is proportional to the elastic modulus of the material, with sign determined by the Poisson's ratio", "C": "The additional pressure follows the Young-Laplace equation but with inverted sign convention for concave/convex surfaces", "D": "The additional pressure depends solely on the contact angle of the liquid, with positive sign for θ<90° and negative for θ>90°" }, "correct_answer": "A", "explanation": "The correct answer is A because the additional pressure on a curved surface is indeed governed by surface tension and curvature, with the sign convention correctly reflecting the surface geometry. Option B introduces a cognitive bias by confusing surface tension effects with bulk material properties. Option C creates a professional intuition trap by presenting a mathematically plausible but physically incorrect sign convention. Option D exploits a common misconception in wetting phenomena by incorrectly attributing the pressure sign to contact angle alone.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1758, "question": "When n spheres form a cubic close packing, what is the number of octahedral voids?", "answer": "n", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求计算立方密堆积中八面体空隙的数量，需要应用材料科学中的晶体结构知识进行数值计算，答案是一个具体的数值(n)。 | 知识层次: 题目需要应用立方密堆积中八面体空隙数量的基本公式，属于直接套用已知知识进行简单计算的情况，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于最低难度等级。题目直接考察立方密堆积中八面体空隙数量的基本公式应用（n个球体对应n个八面体空隙），无需任何计算或推导过程，仅需记忆或识别这一基本知识点即可作答。", "convertible": true, "correct_option": "n", "choice_question": "When n spheres form a cubic close packing, what is the number of octahedral voids?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项B", "B": "选项D", "C": "选项C", "D": "n" }, "correct_answer": "D", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 2079, "question": "Point out the errors in the following concepts and correct them: (20) From a macroscopic perspective, if the liquid-solid interface is straight, it is called a smooth interface structure; if it is zigzag like metal, it is called a rough interface structure.", "answer": "The straight one is called a rough interface structure; the zigzag one is called a smooth interface structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求指出概念错误并进行修正，需要文字解释和论述，而不是简单的选择或判断 | 知识层次: 题目考查的是对液体-固体界面结构的基本概念的记忆和理解，即区分平滑界面结构和粗糙界面结构的定义。虽然需要纠正错误概念，但整体上仍属于基础概念的记忆和简单应用范畴。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生对\"平滑界面结构\"和\"粗糙界面结构\"的定义有准确的理解，并能识别出题目中给出的错误描述。这比单纯记忆定义（等级1）要求更高，需要考生能够辨别概念的正误并进行修正，但不需要进行复杂的体系阐述（等级3）。", "convertible": true, "correct_option": "The straight one is called a rough interface structure; the zigzag one is called a smooth interface structure.", "choice_question": "From a macroscopic perspective, which of the following correctly describes the interface structures?", "conversion_reason": "The original question asks to identify and correct errors in given concepts, which can be rephrased as a multiple-choice question by presenting the correct description among possible options. The answer is a standard concept that can be directly used as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The straight interface is thermodynamically stable due to minimized surface energy", "B": "Zigzag interfaces indicate higher atomic mobility at the solidification front", "C": "The straight one is called a rough interface structure; the zigzag one is called a smooth interface structure", "D": "Interface morphology is primarily determined by the cooling rate rather than atomic attachment kinetics" }, "correct_answer": "C", "explanation": "The correct answer reverses the conventional naming scheme where straight interfaces are typically called smooth and zigzag are called rough. Option A exploits thermodynamic intuition but ignores the kinetic control of interface morphology. Option B uses a plausible-sounding atomic mobility argument that's actually irrelevant to interface classification. Option D strategically confuses processing parameters with fundamental growth mechanisms, a common mistake in rapid solidification scenarios.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 619, "question": "Crystal zone and zone axis", "answer": "Crystal zone and zone axis: The collective term for various sets of crystal planes parallel to the same crystal direction is called a crystal zone, and the crystal direction parallel to these sets of crystal planes is called the zone axis.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对“Crystal zone and zone axis”进行定义和解释，答案以文字形式给出，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目考查晶体学中晶带和晶带轴的基本定义和概念记忆，属于基础概念的理解和表述 | 难度: 在选择题型中，该题目属于概念解释和描述难度等级。题目要求考生理解和记忆晶体带和带轴的定义，虽然涉及两个相关概念，但都属于基础概念记忆范畴，不需要复杂的分析或比较。选择题型中，考生只需识别正确选项，无需进行多步骤推理或复杂概念体系的阐述。", "convertible": true, "correct_option": "The collective term for various sets of crystal planes parallel to the same crystal direction is called a crystal zone, and the crystal direction parallel to these sets of crystal planes is called the zone axis.", "choice_question": "Which of the following correctly describes crystal zone and zone axis?", "conversion_reason": "The answer is a standard definition or concept, which can be converted into a multiple-choice question format by asking for the correct description among options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The collective term for various sets of crystal planes parallel to the same crystal direction is called a crystal zone, and the crystal direction parallel to these sets of crystal planes is called the zone axis.", "B": "A crystal zone refers to a specific crystallographic plane, while the zone axis is the normal vector to that plane.", "C": "Crystal zone describes the periodic arrangement of atoms in a crystal, and zone axis indicates the direction of maximum atomic density.", "D": "A crystal zone is defined by two non-parallel crystal planes, and the zone axis is the line of intersection between these planes." }, "correct_answer": "A", "explanation": "The correct answer A precisely defines crystal zone as sets of planes parallel to a direction, and zone axis as that direction. Option B swaps the relationship between planes and their normal vectors. Option C confuses zone concepts with general crystal structure descriptors. Option D inaccurately limits the definition to only two intersecting planes, missing the broader concept of parallel plane sets.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3561, "question": "When a pure metal undergoes allotropic transformation during cooling from high temperature to room temperature with volume expansion, the atomic coordination number of the low-temperature phase is () compared to that of the high-temperature phase.", "answer": "A", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项中选择正确答案，且提供了选项A作为答案 | 知识层次: 题目考查对同素异构转变过程中原子配位数变化的基础概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 在选择题型中，该题目属于中等偏下难度。虽然涉及同素异构转变和原子配位数的概念，但题目给出了明确的体积膨胀条件，可以直接关联到配位数变化的规律（通常体积膨胀伴随配位数降低）。这需要考生对基本概念有一定理解，但不需要复杂的分析推理过程。", "convertible": true, "correct_option": "A", "choice_question": "When a pure metal undergoes allotropic transformation during cooling from high temperature to room temperature with volume expansion, the atomic coordination number of the low-temperature phase is () compared to that of the high-temperature phase.", "conversion_reason": "The original question is already in a multiple-choice format, which can be directly converted to a single-choice question format without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Lower, due to decreased atomic packing efficiency", "B": "Higher, because volume expansion allows more coordination space", "C": "Identical, as coordination number is independent of phase transformations", "D": "Unpredictable, depending on the specific crystal structure change" }, "correct_answer": "A", "explanation": "The correct answer is A because allotropic transformation with volume expansion typically indicates a less densely packed crystal structure, leading to lower coordination number. Option B exploits the intuitive but incorrect assumption that more space allows higher coordination. Option C targets the common misconception that coordination number remains constant during phase changes. Option D creates uncertainty by suggesting structure-specific behavior when general principles apply.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3587, "question": "Determine the crystal structure for a metal with a0=4.9489 Å, r=1.75 Å and one atom per lattice point.", "answer": "fcc", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求确定金属的晶体结构，需要根据给定的晶格常数和原子半径进行计算和判断，最终给出晶体结构的类型（如fcc）。虽然答案是一个简短的单词，但解答过程需要理解和应用晶体结构的知识，属于简答题的范畴。 | 知识层次: 题目要求根据给定的晶格常数和原子半径确定晶体结构，这需要应用基本的晶体结构计算公式和概念（如原子堆积因子），属于直接套用公式和简单计算的范畴，不需要多步推理或综合分析。 | 难度: 在选择题中属于简单难度，仅需应用基本晶体结构公式（如fcc的原子半径与晶格常数关系r=a0√2/4）进行简单计算验证，无需复杂推理或多步骤分析。题目直接给出所有必要参数，属于\"直接套用公式\"的简单应用层次。", "convertible": true, "correct_option": "fcc", "choice_question": "Determine the crystal structure for a metal with a0=4.9489 Å, r=1.75 Å and one atom per lattice point. The correct crystal structure is:", "conversion_reason": "The answer is a standard term (fcc) which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "fcc", "B": "bcc", "C": "hcp", "D": "simple cubic" }, "correct_answer": "A", "explanation": "The correct answer is fcc because the given atomic radius (1.75 Å) and lattice parameter (4.9489 Å) satisfy the fcc relationship (a0 = 4r/√2). The bcc option is a cognitive bias trap, as the ratio appears close to bcc's √3 relationship but is incorrect. The hcp option exploits the common confusion between close-packed structures. The simple cubic option is a numerical trap, as the ratio superficially resembles a simple cubic structure but would require an impossible packing efficiency.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 730, "question": "A space lattice is formed by arranging in space with a regular repetition. (a) atoms (b) ions (c) geometric points (d) molecules", "answer": "c", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求从给定的选项（a、b、c、d）中选择一个正确答案，符合选择题的特征。 | 知识层次: 题目考查空间点阵的基本概念，即由几何点在空间中规则排列形成，属于基础概念的记忆和理解。 | 难度: 该题目属于基础概念记忆类型，仅需识别\"space lattice\"的定义即可直接选择正确答案。在选择题型中属于最简单的直接记忆类题目，无需理解或辨析其他选项。正确选项(c) geometric points是空间点阵的标准定义，属于材料科学中最基础的概念记忆层次。", "convertible": true, "correct_option": "c", "choice_question": "A space lattice is formed by arranging in space with a regular repetition.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical resolved shear stress for slip in FCC metals is primarily determined by the Peierls-Nabarro stress", "B": "Dislocation climb in BCC metals occurs at temperatures below 0.3Tm due to their high intrinsic point defect concentrations", "C": "The Hall-Petch relationship predicts decreasing yield strength with decreasing grain size in nanocrystalline materials", "D": "Twinning in HCP metals is the dominant deformation mechanism at all temperatures due to their limited slip systems" }, "correct_answer": "C", "explanation": "The correct answer is C because the Hall-Petch relationship breaks down for grain sizes below ~10nm due to the predominance of grain boundary-mediated deformation mechanisms. Option A is incorrect because the Peierls-Nabarro stress is more relevant for BCC metals, while FCC metals are primarily controlled by dislocation interactions. Option B is wrong because dislocation climb requires thermal activation and typically occurs above 0.3Tm. Option D is incorrect because while twinning is important in HCP metals, slip becomes dominant at elevated temperatures. These distractors exploit common misconceptions about deformation mechanisms across different crystal structures and temperature regimes.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4031, "question": "An intermetallic compound is found in the magnesium-gallium system that has a composition of 41.1 wt% Mg - 58.9 wt% Ga. Specify the formula for this compound.(a) MgGa (b) Mg_{2} \\mathrm{Ga} (c) \\mathrm{MgGa}_{2} (d) Mg_{3} \\mathrm{Ga}_{2}", "answer": "(b) Mg_{2}Ga", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从给定的选项中选择正确的化学式，符合选择题的特征 | 知识层次: 题目要求根据给定的重量百分比计算化合物的化学式，涉及基本的原子量计算和简单应用，不需要复杂的分析或综合能力。 | 难度: 在选择题型中，该题目属于简单应用层次，仅需基本公式应用和简单计算即可得出正确答案。题目直接给出了组成百分比，要求选择正确的化学式，解题步骤较为直接，无需复杂变形或多步骤推理。因此，在选择题型内属于较低难度等级。", "convertible": true, "correct_option": "Mg_{2}Ga", "choice_question": "An intermetallic compound is found in the magnesium-gallium system that has a composition of 41.1 wt% Mg - 58.9 wt% Ga. Specify the formula for this compound.", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "MgGa", "B": "Mg_{2}Ga", "C": "MgGa_{2}", "D": "Mg_{3}Ga_{2}" }, "correct_answer": "B", "explanation": "To determine the correct formula, we calculate the atomic ratio using the given weight percentages and atomic masses (Mg: 24.305 g/mol, Ga: 69.723 g/mol). The atomic ratio is approximately 2:1 (Mg:Ga), leading to Mg_{2}Ga. Option A (MgGa) is a simple 1:1 ratio that seems plausible but doesn't match the composition. Option C (MgGa_{2}) reverses the ratio, exploiting a common inversion error. Option D (Mg_{3}Ga_{2}) presents a more complex ratio that might seem correct if miscalculations occur during the atomic ratio determination.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4343, "question": "Compute the maximum mass fraction of proeutectoid cementite possible for a hypereutectoid ironcarbon alloy.", "answer": "the maximum mass fraction of proeutectoid cementite possible for a hypereutectoid iron-carbon alloy is 0.232.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求计算过共析铁碳合金中可能的最大先共析渗碳体质量分数，需要通过数值计算和公式应用来得出具体数值结果0.232。 | 知识层次: 题目需要应用铁碳相图的知识，进行多步计算来确定先共析渗碳体的最大质量分数。这涉及到理解相图中不同区域的组成和相变过程，以及如何应用杠杆定律进行计算。虽然不涉及复杂的机理分析或创新设计，但需要综合理解和应用多个概念。 | 难度: 在选择题中属于中等偏上难度，需要理解铁碳相图、共析反应和杠杆定律等多个概念，并进行多步骤计算。虽然题目给出了正确选项，但解题过程涉及确定合金成分范围、计算共析点前后的相比例等综合分析步骤，比单纯记忆性选择题更复杂。", "convertible": true, "correct_option": "0.232", "choice_question": "What is the maximum mass fraction of proeutectoid cementite possible for a hypereutectoid iron-carbon alloy?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.232", "B": "0.021", "C": "0.067", "D": "0.117" }, "correct_answer": "A", "explanation": "The correct answer is 0.232, calculated using the lever rule at the eutectoid composition (0.76 wt% C) and the maximum solubility of carbon in austenite (2.14 wt% C). Option B (0.021) is the maximum solubility of carbon in ferrite, a common confusion point. Option C (0.067) is the mass fraction of cementite in pearlite, designed to trap those who confuse proeutectoid and eutectoid phases. Option D (0.117) is the mass fraction of cementite at the eutectic point, exploiting confusion between eutectoid and eutectic reactions.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 371, "question": "Which locations may be preferred nucleation sites?", "answer": "Preferred nucleation sites include: original grain boundaries, newly formed high-angle grain boundaries during deformation or those gradually formed through subgrain growth, and the vicinity of second-phase particles.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求解释哪些位置可能是优选的成核位点，答案提供了详细的文字解释和论述，没有涉及选项选择、判断对错或数值计算。 | 知识层次: 题目考查对成核位点的基本概念的记忆和理解，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解和描述多个具体的成核位置（如原始晶界、变形过程中新形成的高角度晶界、亚晶生长逐渐形成的晶界以及第二相粒子附近）。这些知识点虽然属于记忆性内容，但需要考生对成核位置有较为全面的理解和分类能力，而不仅仅是简单的定义记忆。因此，该题目在选择题型中属于等级2难度。", "convertible": true, "correct_option": "original grain boundaries, newly formed high-angle grain boundaries during deformation or those gradually formed through subgrain growth, and the vicinity of second-phase particles", "choice_question": "Which of the following locations may be preferred nucleation sites?", "conversion_reason": "The answer is a standard terminology or concept that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "original grain boundaries, newly formed high-angle grain boundaries during deformation or those gradually formed through subgrain growth, and the vicinity of second-phase particles", "B": "regions with the highest elastic modulus and lowest dislocation density", "C": "areas exhibiting maximum Schmid factor values under applied stress", "D": "locations with perfect crystallographic symmetry and minimum lattice strain" }, "correct_answer": "A", "explanation": "Correct answer A identifies the actual preferred nucleation sites where energy barriers are lowest. Option B exploits cognitive bias by combining two plausible-but-incorrect factors (high modulus and low dislocation density). Option C uses professional intuition trap by referencing the valid Schmid factor concept but misapplying it to nucleation. Option D creates a multi-level verification trap by using perfect symmetry which is thermodynamically unfavorable for nucleation despite seeming intuitive.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4095, "question": "Once the fibers fail in a fibrous composite, catastrophic failure of the piece takes place.(a) True(b) False", "answer": "False. Once the fibers fail in a composite, catastrophic failure of the piece does not take place. Since the broken fibers are still embedded within the matrix, they are still capable of sustaining a diminished load.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求判断陈述的对错，答案明确给出了True或False的选择，并解释了原因。 | 知识层次: 题目考查对复合材料失效行为的基本概念的理解，属于基础知识的记忆和简单应用。 | 难度: 该题目属于概念理解的对错判断，需要考生理解复合材料中纤维失效后的行为，并判断题目陈述的正确性。虽然涉及基础概念，但需要一定的理解深度，而非简单的记忆性知识。", "convertible": true, "correct_option": "False. Once the fibers fail in a composite, catastrophic failure of the piece does not take place. Since the broken fibers are still embedded within the matrix, they are still capable of sustaining a diminished load.", "choice_question": "Once the fibers fail in a fibrous composite, catastrophic failure of the piece takes place.(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials exhibit brittle fracture behavior at room temperature under tensile loading.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature, certain advanced ceramic composites and nanostructured ceramics can exhibit limited plastic deformation. The absolute term 'all' makes this statement false. This tests understanding of exceptions in material behavior and the danger of absolute statements in materials science.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 3, "correct_answers": 2, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 3, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3614, "question": "Determine the minimum radius of an atom that will just fit into the octahedral interstitial site in BCC lithium.", "answer": "0.629 Å", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算确定原子半径的最小值，需要使用公式和已知参数进行计算，最终给出一个具体的数值答案（0.629 Å）。 | 知识层次: 题目需要多步计算和概念关联。首先需要理解BCC晶体结构中八面体间隙的位置和几何特征，然后应用几何关系计算间隙半径，最后结合锂的晶格常数进行计算。这涉及晶体结构知识和几何计算能力的综合应用，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要理解BCC晶体结构、八面体间隙位置的计算方法，并正确应用原子半径与间隙半径的关系公式。解题涉及多步计算和概念关联，但选项已给出正确答案，减少了部分复杂性。", "convertible": true, "correct_option": "0.629 Å", "choice_question": "What is the minimum radius of an atom that will just fit into the octahedral interstitial site in BCC lithium?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.629 Å", "B": "0.414 Å", "C": "0.732 Å", "D": "0.225 Å" }, "correct_answer": "A", "explanation": "The correct answer is A (0.629 Å) because for BCC lithium (r_Li = 1.52 Å), the octahedral interstitial site radius is calculated as r = (√2 - 1)a/2 where a is the lattice parameter. Option B (0.414 Å) is a trap for those who confuse FCC octahedral site geometry with BCC. Option C (0.732 Å) exploits the common mistake of using FCC tetrahedral site calculation. Option D (0.225 Å) targets those who incorrectly use the atomic radius instead of interstitial site calculation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2610, "question": "In the periodic table, what common characteristics do the atomic structures of elements in the same period have?", "answer": "Elements in the same period have the same number of electron shells outside the atomic nucleus.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释元素周期表中同一周期元素的共同特征，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目考查对元素周期表中同周期元素原子结构共同特征的基本概念记忆，仅需要回答电子层数相同这一基本原理，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目属于基本定义简答难度。题目仅要求记忆元素周期表中同一周期元素的共同特征（电子层数相同），不需要进行概念解释或复杂分析。正确选项直接对应基础概念记忆层次，解题步骤简单明了，属于选择题型中最基础的难度等级。", "convertible": true, "correct_option": "Elements in the same period have the same number of electron shells outside the atomic nucleus.", "choice_question": "In the periodic table, what common characteristics do the atomic structures of elements in the same period have?", "conversion_reason": "The answer is a standard concept in chemistry, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Elements in the same period have the same number of electron shells outside the atomic nucleus", "B": "Elements in the same period exhibit identical chemical reactivity due to similar valence electron configurations", "C": "Elements in the same period possess the same number of protons in their atomic nuclei", "D": "Elements in the same period show identical metallic character due to their spatial proximity in the periodic table" }, "correct_answer": "A", "explanation": "The correct answer is A because periodicity is defined by the number of electron shells. Option B is incorrect because chemical reactivity varies significantly within periods due to changing electronegativity. Option C is a proton-counting trap that confuses period with atomic number. Option D exploits the intuitive but incorrect assumption that physical proximity implies property similarity, ignoring the transition from metallic to nonmetallic character across periods.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 202, "question": "Many properties of clay are related to the types of adsorbed cations. Indicate the trend in potential changes of clay after adsorbing the following different cations (use arrows to show: small—large) H+ Al3+ Ba2+ Sr2+ Ca2+ Mg2+ NH4+ K+ Na+ Li+", "answer": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过箭头符号表示不同阳离子吸附后黏土电位变化的趋势，属于需要文字或符号解释的简答题类型。答案形式为一系列符号排列，而非选择、判断或计算。 | 知识层次: 题目要求对不同阳离子吸附后粘土电位变化的趋势进行排序，这需要理解阳离子电荷、离子半径等基本概念，并能够将这些概念综合应用到具体情境中。虽然不涉及复杂的计算或深度机理分析，但需要对多个因素进行综合考虑和比较，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要考生掌握黏土吸附阳离子的特性及其对电位变化的影响趋势。题目要求考生不仅理解不同阳离子的电荷和离子半径对吸附能力的影响，还需要将这些概念综合起来，进行多步比较和排序。正确选项涉及10种不同阳离子的排序，需要考生对离子特性有深入理解并能进行综合分析，这超出了简单记忆或单一概念应用的范畴。", "convertible": true, "correct_option": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "choice_question": "Which of the following correctly shows the trend in potential changes of clay after adsorbing the given cations (from small to large)?", "conversion_reason": "The answer is a specific ordered sequence, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "H+ < Al3+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "B": "Al3+ < H+ < Ba2+ < Sr2+ < Ca2+ < Mg2+ < NH4+ < K+ < Na+ < Li+", "C": "H+ < Al3+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < NH4+ < Li+ < Na+ < K+", "D": "Al3+ < H+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < NH4+ < Li+ < Na+ < K+" }, "correct_answer": "A", "explanation": "正确答案A反映了粘土吸附阳离子后电位变化的实际趋势，基于离子水化半径和电荷密度的综合影响。干扰项B错误地将Al3+置于H+之前，利用了高电荷离子优先吸附的直觉但忽略了H+的特殊性。干扰项C和D故意颠倒碱土金属离子的顺序，利用原子序数增加的直觉（Mg", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答具体的晶体学方向（<111>），需要专业知识解释和论述，而不是简单的选择或判断 | 知识层次: 题目考查对体心立方晶体中最密堆积方向的基本概念记忆，属于基础概念的记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，此题仅需记忆最基本的晶体学方向知识，属于基础概念的直接回忆。题目仅要求识别体心立方晶体中最密排方向，不需要任何解释或分析步骤，符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "<111>", "choice_question": "What is the closest packed direction in a body-centered cubic crystal?", "conversion_reason": "The answer is a standard term in crystallography, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "<111>", "B": "<110>", "C": "<100>", "D": "<112>" }, "correct_answer": "A", "explanation": "The <111> direction is the closest packed in BCC crystals because it aligns with the body diagonal where atoms are in direct contact. Option B (<110>) is a common mistake as it's the closest packed direction in FCC crystals. Option C (<100>) exploits the face diagonal misconception, while Option D (<112>) uses a less common direction that appears plausible but doesn't maximize atomic contact.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4165, "question": "Only pure materials luminesce.(a) True(b) False", "answer": "False. Luminescent materials contain impurities.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错，答案直接给出了True或False的判断结果 | 知识层次: 题目考查对发光材料基本概念的记忆和理解，即纯材料和掺杂材料在发光性质上的区别。 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆纯材料和发光材料的基本定义即可作答，无需深入理解或分析多个概念。", "convertible": true, "correct_option": "False. Luminescent materials contain impurities.", "choice_question": "Only pure materials luminesce.(a) True(b) False", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials exhibit isotropic properties under all conditions.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While amorphous materials generally show isotropic behavior due to their random atomic arrangement, external factors like mechanical stress or thermal gradients can induce anisotropy. The absolute term 'all' and condition 'under all conditions' make this statement false.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3788, "question": "Which of the following oxides is expected to have the largest solid solubility in \\mathrm{Al}_{2} \\mathrm{O}_{3} ?\n(a) \\mathrm{Y}_{2} \\mathrm{O}_{3} (b) \\mathrm{Cr}_{2} \\mathrm{O}_{3} (c) \\mathrm{Fe}_{2} \\mathrm{O}_{3}", "answer": "\\mathrm{cr}_{2} \\mathrm{o}_{3} is expected to have the largest solid solubility in \\mathrm{al}_{2} \\mathrm{o}_{3}; in fact, they are completely soluble in one another.", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求从多个选项中选择具有最大固溶度的氧化物，符合选择题的特征 | 知识层次: 题目需要理解氧化物在Al2O3中的固溶度原理，并分析不同氧化物的离子半径、电荷匹配等因素，属于中等应用层次。 | 难度: 在选择题中属于较高难度，需要综合考虑氧化物晶体结构、离子半径匹配性以及固溶度原理等多个材料科学概念。题目要求判断哪种氧化物在Al₂O₃中具有最大固溶度，这涉及对离子价态匹配（都是+3价氧化物）、离子半径相近性（Cr³⁰与Al³⁺半径最接近）以及晶体结构相容性的综合分析。虽然不涉及计算，但需要运用Hume-Rothery规则等固溶度理论进行多因素判断，比单纯记忆性选择题更具挑战性。", "convertible": true, "correct_option": "(b) \\mathrm{Cr}_{2} \\mathrm{O}_{3}", "choice_question": "Which of the following oxides is expected to have the largest solid solubility in \\mathrm{Al}_{2} \\mathrm{O}_{3}?", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The oxide with the closest ionic radius to Al³⁺", "B": "The oxide with the same crystal structure as Al₂O₃", "C": "The oxide forming the most stable ternary phase with Al₂O₃", "D": "The oxide with the highest melting point in the series" }, "correct_answer": "C", "explanation": "Correct answer is C because solid solubility is primarily determined by thermodynamic stability of the resulting solid solution. Option A exploits the common misconception about ionic radius being the dominant factor. Option B uses the intuitive but incorrect assumption about crystal structure matching. Option D creates a false correlation between melting point and solubility, which are not directly related.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4849, "question": "A metal alloy is known to have electrical conductivity and electron mobility values of 1.2 × 10^{7}(\\Omega·m)^{-1} and 0.0050{m}^{2} / V·s, respectively. A current of 40 \\mathrm{~A} is passed through a specimen of this alloy that is 35mm thick. What magnetic field would need to be imposed to yield a Hall voltage of -3.5 × 10^{-7}V ?", "answer": "the required magnetic field is 0.735, \\text{tesla}.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解所需的磁场强度，答案是一个具体的数值结果（0.735 tesla），符合计算题的特征。 | 知识层次: 题目涉及多步计算和概念关联，需要综合运用电导率、电子迁移率、电流密度和霍尔效应等知识，通过公式推导和数值计算得出结果。虽然不涉及复杂的推理分析或创新应用，但需要一定的综合分析能力。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及电导率、电子迁移率、电流、厚度和霍尔电压等多个物理量的综合计算，解题步骤较为复杂，需要运用霍尔效应的相关公式进行多步推导和计算。虽然题目提供了所有必要的信息，但需要考生具备较强的综合分析能力和计算技巧。", "convertible": true, "correct_option": "0.735 tesla", "choice_question": "A metal alloy is known to have electrical conductivity and electron mobility values of 1.2 × 10^{7}(Ω·m)^{-1} and 0.0050 m^{2}/V·s, respectively. A current of 40 A is passed through a specimen of this alloy that is 35 mm thick. What magnetic field would need to be imposed to yield a Hall voltage of -3.5 × 10^{-7} V?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.735 tesla", "B": "1.47 tesla", "C": "0.368 tesla", "D": "2.94 tesla" }, "correct_answer": "A", "explanation": "正确答案A是通过霍尔效应公式V_H = (IB)/(net)计算得出，其中n=σ/eμ。干扰项B是正确答案的两倍，利用了常见的倍数错误直觉；干扰项C是正确答案的一半，利用了忽略负号导致的符号错误；干扰项D是正确答案的四倍，利用了厚度单位转换错误（将35mm误认为3.5mm）的陷阱。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 596, "question": "The number of atoms in the unit cell of an FCC structure is", "answer": "4", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求回答FCC结构中单位晶胞的原子数，答案是一个具体的数值（4），不需要计算或选择，属于直接回答的简答题类型。 | 知识层次: 题目考查对FCC结构单元晶胞中原子数目的基本概念记忆，属于晶体结构的基础知识，不需要复杂的计算或分析。 | 难度: 在选择题型中，该题目仅考察对FCC结构基本定义的记忆，无需解释或分析，属于最基础的概念记忆题。", "convertible": true, "correct_option": "4", "choice_question": "The number of atoms in the unit cell of an FCC structure is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "选项B", "B": "4", "C": "选项C", "D": "选项D" }, "correct_answer": "B", "explanation": "基于规则生成的备用选项", "sampling_summary": { "result_type": "fallback", "difficulty_label": "unknown_fallback", "total_sampling_attempts": 0, "is_early_stop": false, "is_all_correct": false } }, "generation_status": "success" }, { "idx": 2404, "question": "The shear modulus of Ni is G=75 GPa, and the intrinsic stacking fault energy is γ=150 mJ/m². Calculate the equilibrium width of dislocation extension.", "answer": "Since the perfect dislocation before decomposition is an edge dislocation, the equilibrium width d₀ of the extended dislocation is d₀=Gb²/(8πγ)×(2+ν)/(1−ν)=75×10⁹×(0.147×10⁻⁹)²/(8π×150×10⁻³)×(2+1/3)/(1−1/3) m=1.505×10⁻⁹ m", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求通过给定的公式和参数进行数值计算，最终得出一个具体的数值结果（equilibrium width of dislocation extension）。答案中展示了详细的公式应用和计算过程，符合计算题的特征。 | 知识层次: 题目涉及多步计算和公式应用，需要理解剪切模量、堆垛层错能以及位错扩展平衡宽度的概念，并能够正确代入公式进行计算。虽然计算过程较为直接，但需要对相关物理概念和公式有一定的理解和应用能力。 | 难度: 在选择题中属于高难度，题目涉及多步骤计算和多个物理概念的关联应用（如剪切模量、堆垛层错能、位错扩展宽度公式），需要综合运用材料科学和力学知识进行复杂计算。此外，题目还要求对泊松比等参数有深入理解，并正确代入公式进行推导，这在选择题型中属于较高要求。", "convertible": true, "correct_option": "1.505×10⁻⁹ m", "choice_question": "The shear modulus of Ni is G=75 GPa, and the intrinsic stacking fault energy is γ=150 mJ/m². What is the equilibrium width of dislocation extension?", "conversion_reason": "The calculation question has a specific numerical answer, which can be converted into a multiple-choice format with the correct option being the calculated value.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.505×10⁻⁹ m", "B": "2.257×10⁻⁹ m", "C": "0.753×10⁻⁹ m", "D": "3.010×10⁻⁹ m" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the formula for equilibrium width of dislocation extension: w = G*b²/(4πγ), where b is the Burgers vector (≈2.5×10⁻¹⁰ m for Ni). The incorrect options exploit common errors: B comes from forgetting the 4π factor, C results from using elastic modulus instead of shear modulus, and D is obtained by incorrectly doubling the correct value.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1857, "question": "For an AB-type compound crystal with a face-centered cubic structure, the molecular weight of the AB compound is 26, and its measured density is 2.6g/cm3. Based on this, calculate the unit cell parameter of the AB crystal.", "answer": "The number of formula units per unit cell Z=4, the number of AB molecules in 1mol is 2.6/26×N0=6.02×1022; the number of unit cells=6.02/4×1022=1.5×1022; 1.5×1022V=1.5×1022a3=1021nm3, thus a=0.41nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解晶胞参数，答案中包含了具体的计算步骤和数值结果，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括分子量、密度、单位晶胞参数的计算，并需要理解面心立方结构的基本概念和公式应用。虽然不涉及复杂的推理分析或机理解释，但需要综合运用多个知识点进行计算。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及面心立方结构、分子量、密度和晶胞参数的计算，需要综合运用这些概念进行多步计算。虽然题目提供了正确选项，但解题过程需要理解并关联多个知识点，如公式单位数、摩尔质量、阿伏伽德罗常数等，并进行适当的单位转换和数学运算。这种复杂性在选择题中属于中等偏上的难度。", "convertible": true, "correct_option": "0.41nm", "choice_question": "For an AB-type compound crystal with a face-centered cubic structure, the molecular weight of the AB compound is 26, and its measured density is 2.6g/cm3. Based on this, the unit cell parameter of the AB crystal is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as a choice among other plausible options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.41nm", "B": "0.52nm", "C": "0.38nm", "D": "0.45nm" }, "correct_answer": "A", "explanation": "The correct answer is A (0.41nm) because for an FCC AB-type compound with 4 formula units per unit cell, the lattice parameter a can be calculated using the formula: a = (4M/ρN_A)^(1/3), where M is the molecular weight (26 g/mol), ρ is the density (2.6 g/cm3), and N_A is Avogadro's number. Option B (0.52nm) is a common error from incorrectly assuming a simple cubic structure. Option C (0.38nm) results from miscalculating the number of formula units per cell. Option D (0.45nm) comes from confusing the density with a similar but different compound.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4399, "question": "Cite advantages of cold working.", "answer": "The advantages of cold working are: (1) A high quality surface finish. (2) The mechanical properties may be varied. (3) Close dimensional tolerances.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求列举冷加工的优点，答案以文字解释和论述的形式呈现，没有涉及选择、判断或计算。 | 知识层次: 题目考查对冷加工优点的基本概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目要求考生回忆并列举冷加工的多个优点，涉及基础概念的记忆和简单描述。虽然需要掌握多个知识点，但不需要深入分析或复杂推理，属于概念解释和描述的难度层次。", "convertible": true, "correct_option": "A high quality surface finish, the mechanical properties may be varied, and close dimensional tolerances.", "choice_question": "Which of the following are advantages of cold working?", "conversion_reason": "The answer is a list of standard advantages, which can be converted into a multiple-choice question format by presenting these advantages as options and asking the examinee to select the correct combination.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "A high quality surface finish", "B": "Increased ductility due to dislocation annihilation", "C": "Improved corrosion resistance from oxide layer formation", "D": "Reduced yield strength from thermal relaxation effects" }, "correct_answer": "A", "explanation": "Correct answer is A because cold working produces smooth surfaces through plastic deformation. B is incorrect because cold working increases dislocation density, reducing ductility. C is a trap - while oxide layers may form, they're not inherent to cold working. D reverses the actual effect - cold working increases yield strength through strain hardening.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2952, "question": "When the crystal growth mechanism of Ge (germanium) follows the two-dimensional nucleation model, if the nuclei formed at the liquid-solid interface are cylindrical with each nucleus height h = 0.25 nm, calculate the critical nucleus diameter d*. (Given: melting point Tm = 1231 K, heat of fusion = 750000 kJ/m³, surface energy per unit area = 5.5×10⁻² J/m², undercooling during solidification ΔT = 0.01 Tm)", "answer": "ΔG = π(d/2)²hΔGv + πdhσ\\n\\n∂ΔG/∂d = 0 yields\\nπ(d/2)hΔGv + πhσ = 0\\nd* = -2σ/ΔGv\\nSince ΔGv = -LvΔT/Tm\\nThus, d* = 2σTm/(LvΔT)\\nSubstituting the values gives d* = 14.7 nm", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求进行数值计算和公式应用，解答过程中涉及多个步骤的推导和具体数值的代入计算，最终得出一个具体的数值结果（d* = 14.7 nm）。 | 知识层次: 题目需要进行多步计算，涉及临界核直径的推导和公式应用，需要理解二维成核模型的基本原理，并能够将给定的参数代入公式进行计算。虽然计算过程较为直接，但需要一定的概念关联和综合分析能力。 | 难度: 在选择题中属于中等偏上难度，需要理解二维成核模型、临界核尺寸计算、热力学参数关联等多个概念，并正确应用公式进行多步推导和数值计算。虽然题目提供了所有必要参数，但解题过程涉及公式变形、参数代换和单位换算，对学生的综合分析能力要求较高。", "convertible": true, "correct_option": "14.7 nm", "choice_question": "When the crystal growth mechanism of Ge (germanium) follows the two-dimensional nucleation model, if the nuclei formed at the liquid-solid interface are cylindrical with each nucleus height h = 0.25 nm, what is the critical nucleus diameter d*? (Given: melting point Tm = 1231 K, heat of fusion = 750000 kJ/m³, surface energy per unit area = 5.5×10⁻² J/m², undercooling during solidification ΔT = 0.01 Tm)", "conversion_reason": "The calculation yields a specific numerical answer (14.7 nm), which can be presented as one of the options in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "14.7 nm", "B": "7.35 nm", "C": "29.4 nm", "D": "3.68 nm" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the critical nucleus diameter formula for 2D nucleation: d* = 4γTm/(hΔHfΔT). Plugging in the given values (γ=5.5×10⁻² J/m², Tm=1231 K, h=0.25 nm, ΔHf=750000 kJ/m³, ΔT=12.31 K) yields 14.7 nm. Option B is half the correct value, exploiting the common error of forgetting to multiply by 4 in the formula. Option C is double the correct value, targeting those who might confuse diameter with radius. Option D is one-quarter the correct value, designed to trap those who might incorrectly square the height term.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4656, "question": "Titanium (Ti) has an HCP crystal structure and a density of 4.51 g/cm^3. What is the volume of its unit cell in cubic meters?", "answer": "the volume of the ti unit cell is 1.058 x 10^-28 m^3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解钛的HCP晶胞体积，答案是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目需要应用基本的密度公式和晶体结构知识进行单步计算，属于直接套用公式的简单应用类型。虽然涉及单位换算，但整体思维过程较为直接，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要应用密度公式和晶体结构的基本知识，但解题步骤相对直接，仅需套用密度公式（ρ = m/V）并结合钛的原子质量和HCP晶胞的原子数进行计算。不需要复杂的推导或多步骤转换，因此属于等级2难度。", "convertible": true, "correct_option": "1.058 x 10^-28 m^3", "choice_question": "Titanium (Ti) has an HCP crystal structure and a density of 4.51 g/cm^3. What is the volume of its unit cell in cubic meters?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.058 x 10^-28 m^3", "B": "3.62 x 10^-29 m^3", "C": "2.16 x 10^-28 m^3", "D": "5.29 x 10^-29 m^3" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算HCP结构的单位晶胞体积得出的。干扰项B利用了HCP结构中原子堆积因子(0.74)的倒数关系进行错误计算。干扰项C是基于FCC结构的错误类比计算。干扰项D是正确数值的一半，利用了HCP结构中2个原子的特性进行迷惑性设计。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2940, "question": "The fundamental reason for diffusion to occur in materials is (A) temperature change (B) concentration gradient (C) chemical potential gradient", "answer": "C", "question_type": "multiple_choice", "question_type_name": "选择题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求从选项（A、B、C）中选择正确答案 | 知识层次: 题目考查扩散现象的基本原因，属于材料科学中的基础概念记忆和理解，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生理解扩散现象的根本原因，并区分温度变化、浓度梯度和化学势梯度这三个选项之间的差异。正确选项（化学势梯度）不是最直观的选项，需要一定的概念理解和简单辨析能力。", "convertible": true, "correct_option": "C", "choice_question": "The fundamental reason for diffusion to occur in materials is", "conversion_reason": "The original question is already in a multiple-choice format with a single correct answer, making it directly convertible to a single-choice question without modification.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The driving force is always proportional to the square root of temperature", "B": "It occurs primarily due to vacancy concentration differences", "C": "The process is fundamentally governed by the second law of thermodynamics", "D": "Atomic vibrations create spontaneous directional movement" }, "correct_answer": "C", "explanation": "The correct answer is C because diffusion is fundamentally a thermodynamic process driven by entropy maximization (second law). Option A is a trap using the temperature dependence of diffusion coefficient but misrepresents the driving force. Option B exploits common confusion between mechanism (vacancies) and driving force. Option D creates a false intuition about atomic vibrations while ignoring their random nature.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3552, "question": "Someone said: 'A precipitation-hardening alloy can be softened by water quenching at an appropriate temperature.' Is this statement correct? Explain.", "answer": "A precipitation-hardening alloy cannot be softened by water quenching at an appropriate temperature. The reason is that when heated to a high temperature, it forms a single solid solution structure. Rapid cooling results in a single solid solution, which, although not very hard at this stage, will subsequently undergo precipitation hardening. Therefore, a precipitation-hardening alloy can only be softened through an aging process.", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求判断陈述的对错，并解释原因。答案中明确指出了陈述是错误的，并提供了详细的解释。 | 知识层次: 题目不仅需要理解沉淀硬化合金的基本概念，还需要分析水淬对其性能的影响，并解释为什么水淬不能软化合金，而是需要通过时效过程来实现。这涉及到多步概念关联和综合分析。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目要求判断一个关于沉淀硬化合金软化过程的陈述是否正确，这需要考生对沉淀硬化合金的热处理过程有深入的理解。其次，正确选项不仅需要判断陈述的正误，还需要解释原因，涉及多步概念关联和综合分析。具体来说，考生需要理解高温下形成单一固溶体结构、快速冷却后的状态以及后续沉淀硬化的过程，这些知识点需要较高的综合分析能力。因此，该题目在选择题型内属于等级4的难度。", "convertible": true, "correct_option": "A precipitation-hardening alloy cannot be softened by water quenching at an appropriate temperature. The reason is that when heated to a high temperature, it forms a single solid solution structure. Rapid cooling results in a single solid solution, which, although not very hard at this stage, will subsequently undergo precipitation hardening. Therefore, a precipitation-hardening alloy can only be softened through an aging process.", "choice_question": "Someone said: 'A precipitation-hardening alloy can be softened by water quenching at an appropriate temperature.' Is this statement correct? Explain.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All precipitation-hardening alloys can be softened by solution treatment followed by rapid quenching.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While solution treatment and rapid quenching can produce a supersaturated solid solution that appears 'soft', this is not true softening but rather an intermediate state before aging. True softening requires prolonged annealing to allow complete precipitate dissolution and grain growth. The statement is misleading because it conflates temporary solution softening with permanent softening mechanisms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3728, "question": "A Brinell hardness measurement, using a 10-mm-diameter indenter and a 500-kg load, produces an indentation of 4.5mm on an aluminum plate. Determine the Brinell hardness number (HB) of the metal.", "answer": " hb = 29.8 ", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（Brinell硬度计算公式）来求解硬度值，答案是一个具体的数值结果。 | 知识层次: 题目考查基本公式应用和简单计算，只需套用Brinell硬度计算公式即可得出结果，无需多步计算或综合分析。 | 难度: 在选择题型内，该题目属于单一公式直接计算的难度等级。题目要求计算布氏硬度数（HB），只需直接套用布氏硬度的基本公式进行计算，无需额外的概念理解或复杂的解题步骤。题目提供了所有必要的参数（压头直径、载荷、压痕直径），学生只需将这些数值代入公式即可得出正确答案。因此，在选择题型中，该题目属于最简单的难度等级。", "convertible": true, "correct_option": "29.8", "choice_question": "A Brinell hardness measurement, using a 10-mm-diameter indenter and a 500-kg load, produces an indentation of 4.5mm on an aluminum plate. What is the Brinell hardness number (HB) of the metal?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "29.8", "B": "59.6", "C": "14.9", "D": "119.2" }, "correct_answer": "A", "explanation": "The correct answer is A (29.8) calculated using the Brinell hardness formula HB = (2P)/(πD(D-√(D²-d²))). Option B (59.6) doubles the correct value, exploiting the common error of forgetting to halve the indentation diameter. Option C (14.9) is half the correct value, targeting those who mistakenly use radius instead of diameter. Option D (119.2) quadruples the correct value, preying on those who confuse load units or misapply the formula.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4365, "question": "Name the microstructural products of eutectoid iron-carbon alloy (0.76 wt% C) specimens that are first completely transformed to austenite, then cooled to room temperature at a rate of 200°C/s.", "answer": "At a rate of 200°C/s, only martensite forms.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求描述特定条件下的微观结构产物，答案需要文字解释而非选择、判断或计算。 | 知识层次: 题目要求考生理解并应用铁碳合金相变的基本原理，根据冷却速率判断微观结构产物。这需要将相变动力学知识与具体冷却条件（200°C/s）相结合进行分析，属于中等应用层次。虽然不涉及复杂计算，但需要理解连续冷却转变图（CCT图）的概念，并能够将冷却速率与相变产物对应起来。 | 难度: 在选择题中属于中等难度，需要理解多个概念并进行比较分析。题目涉及铁碳合金的微观结构转变，需要掌握奥氏体转变和马氏体形成的条件，以及冷却速率对微观结构的影响。虽然题目给出了具体的冷却速率，但需要考生能够将这一信息与马氏体形成的条件联系起来，进行综合分析。", "convertible": true, "correct_option": "Only martensite forms", "choice_question": "What are the microstructural products of eutectoid iron-carbon alloy (0.76 wt% C) specimens that are first completely transformed to austenite, then cooled to room temperature at a rate of 200°C/s?", "conversion_reason": "The answer is a standard term (martensite) and the question can be rephrased to fit a multiple-choice format by providing options such as different microstructural products.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Only martensite forms", "B": "Pearlite and bainite mixture", "C": "Austenite with retained martensite", "D": "Proeutectoid ferrite and pearlite" }, "correct_answer": "A", "explanation": "At a cooling rate of 200°C/s, the eutectoid composition steel will bypass both pearlite and bainite formation regions, resulting in complete martensitic transformation. Option B is incorrect because this cooling rate is too fast for pearlite or bainite formation. Option C is wrong because austenite cannot be retained at room temperature in plain carbon steels. Option D is a distractor based on slower cooling rates where proeutectoid phases would form first.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4853, "question": "Consider a parallel-plate capacitor having an area of 3225 mm2 (5 in.2), a plate separation of 1mm (0.04 in.), and a material having a dielectric constant of 3.5 positioned between the plates. Compute the electric field that must be applied for 2 × 10−8 C to be stored on each plate.", "answer": "the electric field that must be applied is 2.0 × 105 v/m.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算和公式应用，涉及电容器的面积、板间距、介电常数等参数，最终需要计算出电场强度。答案也是一个具体的数值结果，符合计算题的特征。 | 知识层次: 题目涉及基本的电容公式应用和简单计算，如电容公式C=εA/d和电场强度E=V/d的直接套用，无需多步计算或综合分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。题目要求计算平行板电容器中的电场强度，涉及的基本公式为电容的定义式C=Q/V和电容与电场的关系式E=V/d。虽然需要应用两个公式，但步骤直接且计算简单，属于基础知识的直接应用。因此，在选择题型内属于等级2难度。", "convertible": true, "correct_option": "2.0 × 10^5 v/m", "choice_question": "Consider a parallel-plate capacitor having an area of 3225 mm2 (5 in.2), a plate separation of 1mm (0.04 in.), and a material having a dielectric constant of 3.5 positioned between the plates. What is the electric field that must be applied for 2 × 10−8 C to be stored on each plate?", "conversion_reason": "The question is a calculation problem with a definite numerical answer, which can be converted into a multiple-choice question format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "2.0 × 10^5 V/m", "B": "1.8 × 10^5 V/m", "C": "2.2 × 10^5 V/m", "D": "7.0 × 10^5 V/m" }, "correct_answer": "A", "explanation": "The correct answer is A (2.0 × 10^5 V/m) calculated using E = Q/(ε₀κA) where κ is the dielectric constant. Option B (1.8 × 10^5 V/m) exploits the cognitive bias of rounding down the dielectric constant to 3.0. Option C (2.2 × 10^5 V/m) tempts with a plausible overestimation by neglecting the dielectric effect. Option D (7.0 × 10^5 V/m) is a professional intuition trap that incorrectly uses the dielectric constant directly as a multiplier for the field.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4515, "question": "For the following pair of polymers, do the following: (1) state whether or not it is possible to determine whether one polymer has a higher melting temperature than the other; (2) if it is possible, note which has the higher melting temperature and then cite reason(s) for your choice; and (3) if it is not possible to decide, then state why. Isotactic polystyrene that has a density of 1.12 g/cm3 and a weight-average molecular weight of 150,000 g/mol; syndiotactic polystyrene that has a density of 1.10 g/cm3 and a weight-average molecular weight of 125,000 g/mol", "answer": "Yes, it is possible to determine which of the two polystyrenes has the higher Tm. The isotactic polystyrene will have the higher melting temperature because it has a higher density (i.e., less branching) and also the greater weight-average molecular weight.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来回答问题，包括判断可能性、比较熔点高低并给出理由，或说明无法决定的原因。答案需要详细的文字说明而非简单选择或计算。 | 知识层次: 题目要求比较两种聚合物的熔点，并解释原因。这涉及到对聚合物结构（等规和间规）、密度和分子量对熔点影响的理解和应用。虽然不需要复杂的计算或深入机理分析，但需要综合多个因素进行判断和解释，属于中等应用层次。 | 难度: 在选择题中属于较高难度，题目要求考生不仅理解聚合物的立体规整性（等规与间规）对熔点的影响，还需要综合考虑密度（反映分子链堆积紧密程度）和分子量这两个因素对熔点的复合影响。需要考生进行多角度分析（立体构型+密度+分子量）并正确判断各因素的优先级（立体构型影响>密度影响>分子量影响），最后得出综合结论。这种需要同时处理多个变量并理解其相互作用关系的题目，在选择题型中属于较复杂的综合分析题。", "convertible": true, "correct_option": "The isotactic polystyrene will have the higher melting temperature because it has a higher density (i.e., less branching) and also the greater weight-average molecular weight.", "choice_question": "For the following pair of polymers, which one has a higher melting temperature and why? Isotactic polystyrene that has a density of 1.12 g/cm3 and a weight-average molecular weight of 150,000 g/mol; syndiotactic polystyrene that has a density of 1.10 g/cm3 and a weight-average molecular weight of 125,000 g/mol", "conversion_reason": "The original question is a short answer question that asks for a determination and explanation regarding the melting temperature of two polymers. The answer is specific and can be converted into a multiple-choice format by presenting the correct explanation as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": "None", "perplexity_level": "None", "perplexity_reason": "The question provides all necessary information for a materials science graduate student to compare the melting temperatures of isotactic and syndiotactic polystyrene based on their density and weight-average molecular weight. The question is designed to test the student's understanding of how polymer structure and properties influence melting temperature, and all required data is explicitly given.", "missing_info": "None" }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Syndiotactic polystyrene due to its higher degree of crystallinity from regular side group arrangement", "B": "Isotactic polystyrene because of its higher density and molecular weight", "C": "Cannot be determined without knowing the glass transition temperatures", "D": "Both have identical melting points as they are chemically identical" }, "correct_answer": "B", "explanation": "The correct answer is B because higher density indicates less branching and better chain packing, while higher molecular weight contributes to stronger intermolecular forces - both factors increase melting temperature. Option A is a cognitive bias trap exploiting the common misconception that syndiotactic always has higher crystallinity. Option C is a verification trap using an irrelevant parameter (Tg). Option D is a professional intuition trap suggesting chemical identity overrides structural differences.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1343, "question": "How does the concentration of a solid solution affect the diffusion coefficient?", "answer": "The higher the concentration, the easier the diffusion.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释固体溶液浓度对扩散系数的影响，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释固体溶液浓度对扩散系数的影响，需要理解扩散机制和浓度效应的关联，进行概念关联和综合分析，而不仅仅是记忆基础概念或简单应用。 | 难度: 在选择题中属于中等难度，需要理解固体溶液的浓度与扩散系数之间的关系，并能综合分析浓度变化对扩散过程的影响。虽然题目涉及的概念较为基础，但需要将多个知识点关联起来进行分析，因此难度适中。", "convertible": true, "correct_option": "The higher the concentration, the easier the diffusion.", "choice_question": "How does the concentration of a solid solution affect the diffusion coefficient?", "conversion_reason": "The answer is a standard statement that can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The higher the concentration, the easier the diffusion due to increased vacancy concentration", "B": "The lower the concentration, the easier the diffusion due to reduced lattice distortion", "C": "Diffusion coefficient is independent of concentration in solid solutions", "D": "The relationship follows an inverse square root dependence on concentration" }, "correct_answer": "A", "explanation": "Correct answer A leverages the vacancy-mediated diffusion mechanism where higher solute concentrations increase vacancy concentrations. Option B uses the common misconception about lattice distortion effects overriding vacancy effects. Option C exploits the AI's tendency to oversimplify complex relationships. Option D introduces a mathematically plausible but physically incorrect relationship to trap pattern-recognition algorithms.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1236, "question": "In polycrystals, grain boundaries are classified into large-angle and small-angle grain boundaries. What is the meaning of the angle?", "answer": "The misorientation between adjacent grains", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求对“angle”的含义进行文字解释和论述，答案是一个简短的文字描述，而非选择、判断或计算。 | 知识层次: 题目考查对晶界角度定义的基本概念记忆和理解，属于材料科学中的基础知识点。 | 难度: 在选择题型中，该题目仅考察对基本定义的记忆，即\"晶界角度\"的含义。正确选项直接给出了定义（相邻晶粒之间的取向差），无需任何解释或推理步骤。这属于最基础的概念记忆题，符合等级1的简单定义要求。", "convertible": true, "correct_option": "The misorientation between adjacent grains", "choice_question": "In polycrystals, grain boundaries are classified into large-angle and small-angle grain boundaries. What does the angle refer to?", "conversion_reason": "The answer is a standard terminology or concept, which can be converted into a multiple-choice question format by providing the correct option and distractor options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The misorientation between adjacent grains", "B": "The angle of dislocation arrays at the boundary", "C": "The contact angle between grain surfaces", "D": "The critical angle for total internal reflection at the boundary" }, "correct_answer": "A", "explanation": "The correct answer is A because the angle in grain boundary classification specifically refers to the misorientation between the crystallographic orientations of adjacent grains. Option B is a cognitive bias trap, as dislocation arrays are related to small-angle boundaries but not the defining feature. Option C exploits surface science intuition incorrectly. Option D is a physics concept that doesn't apply to grain boundary characterization.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 69, "question": "What is the effect of Al3+ replacing Si4+ on the composition of silicates?", "answer": "The replacement of Si4+ by Al3+ is a partial substitution. When Al3+ replaces Si4+, the structural units [AlSiO4][AlSiO5] lose electrical neutrality, resulting in excess negative charge. To maintain electrical neutrality, some larger cations with lower charges such as K+, Ca2+, and Ba2+ will enter the structure.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释Al3+替换Si4+对硅酸盐组成的影响，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目涉及硅酸盐中Al3+替代Si4+的效应，需要理解离子替代对结构电中性的影响，并关联到补偿阳离子的引入。这需要多步概念关联和综合分析，而不仅仅是基础概念的记忆或简单应用。 | 难度: 在选择题型中，该题目属于较高难度。题目不仅要求考生理解Al3+取代Si4+的基本概念，还需要综合分析这种取代对硅酸盐结构电中性的影响，以及后续引入补偿阳离子的机制。解题过程涉及多步逻辑推理和概念关联（如离子取代、电荷平衡、补偿阳离子选择等），超出了简单记忆或单一概念应用的范畴。在选择题型内，这种需要综合多个知识点并推导结论的题目属于较难水平。", "convertible": true, "correct_option": "The replacement of Si4+ by Al3+ is a partial substitution. When Al3+ replaces Si4+, the structural units [AlSiO4][AlSiO5] lose electrical neutrality, resulting in excess negative charge. To maintain electrical neutrality, some larger cations with lower charges such as K+, Ca2+, and Ba2+ will enter the structure.", "choice_question": "What is the effect of Al3+ replacing Si4+ on the composition of silicates?", "conversion_reason": "The answer is a standard explanation that can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The substitution creates excess positive charge, requiring incorporation of anions like F- for charge balance", "B": "The replacement is isovalent and requires no additional charge compensation", "C": "The structural units lose electrical neutrality, requiring larger cations like K+ to enter the structure", "D": "The Al3+ substitution increases the polymerization degree of silicate tetrahedra" }, "correct_answer": "C", "explanation": "The correct answer is C because Al3+ replacing Si4+ creates excess negative charge (not positive as in A), requiring larger cations for charge balance. Option B is wrong because the substitution is aliovalent (not isovalent). Option D is incorrect because Al substitution actually decreases polymerization degree. Option A uses a common misconception about charge sign reversal, while B exploits the isovalent substitution intuition from other systems.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 6, "correct_answers": 5, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 6, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3603, "question": "A typical paper clip weighs 0.59g and consists of BCC iron. Calculate the number of iron atoms in the paper clip.", "answer": "6.37 × 10^21 atoms", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算铁原子数量），需要应用公式（通过质量和晶体结构计算原子数），答案是一个具体的数值结果。 | 知识层次: 题目需要进行基本的数值计算和公式应用，涉及摩尔质量和阿伏伽德罗常数的直接套用，属于简单应用层次。虽然需要理解BCC结构的概念，但计算过程相对直接，不涉及多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算。虽然需要运用BCC铁的单位晶胞原子数和摩尔质量等基本概念，但解题步骤较为直接，只需套用摩尔质量和阿伏伽德罗常数进行简单计算即可得出答案。相比单一公式直接计算的题目，该题需要稍多的知识应用，但不需要多个公式组合或复杂分析，因此在选择题型中属于等级2难度。", "convertible": true, "correct_option": "6.37 × 10^21 atoms", "choice_question": "A typical paper clip weighs 0.59g and consists of BCC iron. The number of iron atoms in the paper clip is:", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "6.37 × 10^21 atoms", "B": "1.27 × 10^22 atoms", "C": "3.18 × 10^21 atoms", "D": "2.54 × 10^22 atoms" }, "correct_answer": "A", "explanation": "正确答案A是通过计算铁原子摩尔质量(55.85g/mol)和BCC结构每个晶胞含2个铁原子得出的。干扰项B是错误地将BCC结构视为FCC(每个晶胞4个原子)计算的结果，利用了晶体结构混淆策略。干扰项C是仅计算了质量而未考虑BCC结构特性的错误结果，属于认知偏差陷阱。干扰项D是同时犯了晶体结构错误和计算错误的双重陷阱，数值与正确答案呈整数倍关系以增加迷惑性。", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2887, "question": "If O:Si ≈ 2.5 is the criterion for glass-forming tendency, what is the maximum amount of Na2O that can form a glass?", "answer": "Let the maximum content of Na2O be x, and SiO2 = 1 - x. According to (x + 2(1 - x)) / (1 - x) ≤ 2.5, we get (2 - x) / (1 - x) ≤ 2.5. Further derivation yields 1 + 1 / (1 - x) ≤ 2.5; 1 / (1 - x) ≤ 1.5; 1 - x ≥ 1 / 1.5; x ≤ 1 / 3. Therefore, the maximum amount of Na2O that can form a glass is 1/3.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目需要通过数值计算和公式应用来求解最大Na2O含量，答案展示了具体的计算过程和推导步骤，符合计算题的特征。 | 知识层次: 题目需要进行多步计算和公式应用，涉及玻璃形成倾向的判定标准（O:Si ≈ 2.5）以及Na2O和SiO2的比例关系。虽然计算过程较为直接，但需要理解并应用相关概念和公式，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解玻璃形成倾向的O:Si比例标准，并进行多步数学推导和不等式求解。虽然题目给出了明确的解题路径，但仍需要较强的概念关联和综合分析能力。", "convertible": true, "correct_option": "1/3", "choice_question": "If O:Si ≈ 2.5 is the criterion for glass-forming tendency, what is the maximum amount of Na2O that can form a glass?", "conversion_reason": "The calculation leads to a specific numerical answer (1/3), which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1/3", "B": "1/2", "C": "2/5", "D": "1/4" }, "correct_answer": "A", "explanation": "The correct answer is A (1/3) because for each Na2O added, it provides 1 oxygen and consumes 1 Si (as SiO2). To maintain O:Si ≈ 2.5, the maximum Na2O fraction is 1/3. Option B (1/2) is a cognitive bias trap - it seems plausible for simple stoichiometry but violates the glass-forming criterion. Option C (2/5) exploits numerical proximity to 2.5 but misapplies the ratio logic. Option D (1/4) is a professional intuition trap - it seems conservative enough but actually underrepresents the maximum possible doping while maintaining glass formation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2246, "question": "If an alloy has β-phase precipitates with a spacing of 50 nm after heat treatment, calculate the total area of α/β interfaces per cubic meter (assuming the precipitates are cubes).", "answer": "The number of β precipitates is n_β=1/(50×10^-9)^3=8×10^21. The surface area of each β is S_β=6×(50×10^-9)^2=1.5×10^-14 m^2. The total interface area in 1 m^3 is S_A=8×10^21×1.5×10^-14=1.2×10^8 m^2.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过数值计算和公式应用来求解α/β界面的总面积，答案中包含了具体的计算步骤和数值结果。 | 知识层次: 题目需要进行多步计算，包括计算β相析出物的数量、每个β相的表面积以及总的界面面积。虽然计算过程相对直接，但需要理解析出物间距与数量的关系，以及立方体表面积的计算方法，涉及一定的概念关联和综合分析。 | 难度: 在选择题中属于中等偏上难度，需要理解合金相变、沉淀相间距计算、几何形状假设（立方体）、表面积计算等多个概念，并进行多步骤的综合计算。虽然题目提供了明确的解题路径，但涉及的知识点较多且需要准确串联各步骤，属于综合性计算问题。", "convertible": true, "correct_option": "1.2×10^8 m^2", "choice_question": "If an alloy has β-phase precipitates with a spacing of 50 nm after heat treatment, what is the total area of α/β interfaces per cubic meter (assuming the precipitates are cubes)?", "conversion_reason": "The answer is a specific numerical value, which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "1.2×10^8 m^2", "B": "6.0×10^7 m^2", "C": "2.4×10^8 m^2", "D": "3.0×10^7 m^2" }, "correct_answer": "A", "explanation": "The correct answer A (1.2×10^8 m^2) is calculated by considering the cubic precipitate arrangement with 50 nm spacing. Each cube has 6 faces, and the interface area per unit volume is 6/(50 nm)^2. Option B (6.0×10^7 m^2) is a common mistake from only counting 3 visible faces of the cubes. Option C (2.4×10^8 m^2) doubles the correct value by incorrectly assuming precipitates are touching. Option D (3.0×10^7 m^2) comes from miscalculating the spacing as 100 nm instead of 50 nm.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1459, "question": "For cold-formed components, (47) annealing should be performed promptly after forming to remove (48) and prevent the components from (49) or (50) during use.", "answer": "stress relief; residual internal stress; deformation; cracking", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求填写特定术语来完成句子，答案需要文字解释和论述，而不是从选项中选择或进行数值计算。 | 知识层次: 题目主要考查对冷成型组件后处理工艺（应力退火）及其目的（消除残余内应力、防止变形和开裂）的基础概念记忆，属于材料科学中热处理工艺的基本知识点，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目涉及的是基础概念记忆，但需要考生准确理解冷成型组件的后处理工艺及其目的，包括应力消除、残余内应力、变形和开裂等概念。题目要求考生在给定的选项中选出正确的术语填空，这需要一定的概念理解和记忆能力，但不需要复杂的分析或推理过程。因此，难度等级为2。", "convertible": true, "correct_option": "stress relief; residual internal stress; deformation; cracking", "choice_question": "For cold-formed components, which of the following should be performed promptly after forming to remove residual internal stress and prevent the components from deformation or cracking during use?", "conversion_reason": "The original short answer question has a specific and standard answer that can be converted into a multiple-choice format by rephrasing the question to ask for the correct combination of terms.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Stress relief annealing at 0.3-0.5Tm for 1 hour", "B": "Solution treatment at 0.8Tm followed by quenching", "C": "Recrystallization annealing at 0.6Tm with slow cooling", "D": "Normalizing at 0.9Tm with air cooling" }, "correct_answer": "A", "explanation": "Correct answer A uses the precise temperature range (0.3-0.5Tm) and duration specifically effective for stress relief without causing grain growth. Option B is a cognitive bias trap - solution treatment is for alloys not cold-worked metals. Option C exploits professional intuition - recrystallization is excessive for simple stress relief. Option D is a multi-level trap - normalizing creates new stresses while appearing to be a thermal treatment.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1792, "question": "Structurally compare the arrangement of silicon-oxygen frameworks in silicate crystals and silicate glasses", "answer": "In silicate crystals, the silicon-oxygen frameworks are arranged in an orderly manner according to certain symmetrical rules; in silicate glasses, the arrangement of silicon-oxygen frameworks is disordered.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求对硅酸盐晶体和硅酸盐玻璃中硅氧骨架的排列进行结构比较，答案需要文字解释和论述，没有提供选项或要求判断对错，也不涉及数值计算。 | 知识层次: 题目主要考查对硅酸盐晶体和玻璃中硅氧骨架排列方式的基本概念记忆和理解，属于基础概念层面的知识。 | 难度: 在选择题型中，该题目要求考生理解和比较硅酸盐晶体和硅酸盐玻璃中硅氧骨架的排列方式。虽然涉及两个概念的比较，但知识点较为基础，属于定义和基本原理的记忆性知识。解题步骤相对简单，只需识别和区分两种材料的结构特征，无需复杂的分析或推理过程。因此，在选择题型内属于中等难度（等级2）。", "convertible": true, "correct_option": "In silicate crystals, the silicon-oxygen frameworks are arranged in an orderly manner according to certain symmetrical rules; in silicate glasses, the arrangement of silicon-oxygen frameworks is disordered.", "choice_question": "Which of the following correctly compares the arrangement of silicon-oxygen frameworks in silicate crystals and silicate glasses?", "conversion_reason": "The answer is a clear, factual comparison that can be presented as a correct option among other plausible but incorrect alternatives.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "In silicate crystals, the silicon-oxygen frameworks are arranged in an orderly manner according to certain symmetrical rules; in silicate glasses, the arrangement of silicon-oxygen frameworks is disordered", "B": "Both silicate crystals and glasses exhibit long-range order in silicon-oxygen frameworks, but with different symmetry elements", "C": "Silicate glasses maintain short-range order similar to crystals, but with varying bond angles that disrupt medium-range order", "D": "The primary difference lies in the coordination number of silicon atoms: 4 in crystals and variable in glasses" }, "correct_answer": "A", "explanation": "The correct answer A precisely distinguishes the fundamental structural difference between crystalline and glassy silicates. Option B is incorrect because glasses lack long-range order. Option C contains a partial truth about short-range order but is misleading as a comparison. Option D exploits the common misconception about coordination number changes, while in reality Si maintains tetrahedral coordination in both phases.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 146, "question": "What are the kinetic factors affecting the glass formation process?", "answer": "The key factor affecting glass formation is the cooling rate of the melt. Whether the melt crystallizes or forms glass is related to the degree of supercooling, viscosity, nucleation rate, and crystal growth rate.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释影响玻璃形成过程的动力学因素，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释影响玻璃形成过程的动力学因素，涉及多个相关概念（冷却速率、过冷度、粘度、成核速率、晶体生长速率）的关联和综合分析，需要理解这些因素之间的相互作用及其对玻璃形成的影响，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解多个概念（冷却速率、过冷度、粘度、成核速率和晶体生长速率）并进行综合分析。虽然题目涉及多个因素，但在选择题型中只需识别关键因素，不需要进行多步计算或深度关联性分析。", "convertible": true, "correct_option": "The key factor affecting glass formation is the cooling rate of the melt. Whether the melt crystallizes or forms glass is related to the degree of supercooling, viscosity, nucleation rate, and crystal growth rate.", "choice_question": "Which of the following best describes the kinetic factors affecting the glass formation process?", "conversion_reason": "The answer provided is a standard and concise explanation of the kinetic factors affecting glass formation, making it suitable for conversion into a multiple-choice question format where the given answer can serve as the correct option.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The critical cooling rate is determined solely by the melting temperature of the material", "B": "Glass formation is primarily controlled by the equilibrium phase diagram boundaries", "C": "The key factor is the cooling rate of the melt, involving supercooling, viscosity, nucleation rate, and crystal growth rate", "D": "The most important kinetic factor is the thermal conductivity of the material at room temperature" }, "correct_answer": "C", "explanation": "The correct answer C captures the comprehensive kinetic factors including cooling rate, supercooling, viscosity, nucleation and growth rates. Option A is a cognitive bias trap using the intuitive but incorrect melting temperature focus. Option B exploits professional intuition by suggesting equilibrium phase diagrams control this non-equilibrium process. Option D uses a real material property (thermal conductivity) but in the wrong context (room temperature instead of melt conditions).", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 1, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4845, "question": "Predict whether Indium (In) will act as a donor or an acceptor when added to Cadmium Sulfide (CdS). Assume that the impurity elements are substitutional.", "answer": "Indium will act as a donor in CdS. Since In is from group IIIA of the periodic table, it will substitute for Cd; an In atom has one more valence electron than a Cd atom.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求预测铟在硫化镉中的行为并解释原因，需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求分析掺杂元素在半导体中的行为，需要理解元素周期表中族的概念、价电子数的差异以及掺杂对半导体导电类型的影响。这涉及多步概念关联和综合分析，但不需要复杂的机理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解元素周期表中元素的族属性和价电子数目的概念，并能够将这一知识应用到具体的半导体材料掺杂情境中。解题步骤涉及识别In和Cd的价电子差异，并推断出掺杂后的电子行为。虽然不需要复杂的计算，但需要综合分析和概念关联的能力。", "convertible": true, "correct_option": "Indium will act as a donor in CdS.", "choice_question": "Predict whether Indium (In) will act as a donor or an acceptor when added to Cadmium Sulfide (CdS). Assume that the impurity elements are substitutional.", "conversion_reason": "The answer is a standard and concise statement that can be directly used as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Donor (n-type)", "B": "Acceptor (p-type)", "C": "Amphoteric (both donor and acceptor)", "D": "Neutral impurity (no doping effect)" }, "correct_answer": "A", "explanation": "Indium (In) has a valence of +3 while Cadmium (Cd) is +2. When In substitutes for Cd in CdS, it donates one extra electron to the conduction band, acting as a donor. Option B exploits the common misconception that group III elements always act as acceptors. Option C creates confusion by suggesting amphoteric behavior which requires specific defect chemistry conditions. Option D plays on the rare cases where impurities don't affect carrier concentration.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1889, "question": "5．According to the thermodynamic theory of diffusion, the driving force of the diffusion process is", "answer": "chemical potential gradient", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释扩散过程的驱动力，需要文字回答，而不是选择、判断或计算 | 知识层次: 题目考查扩散过程驱动力的基本概念记忆，即化学势梯度，属于基础概念的记忆性知识。 | 难度: 在选择题型中，该题目仅考察对扩散过程驱动力的基础定义记忆，属于最基础的概念性知识。学生只需识别\"chemical potential gradient\"这一标准术语即可作答，无需进行概念解释或复杂分析，符合等级1\"基本定义简答\"的特征。", "convertible": true, "correct_option": "chemical potential gradient", "choice_question": "According to the thermodynamic theory of diffusion, the driving force of the diffusion process is:", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "chemical potential gradient", "B": "concentration gradient", "C": "temperature gradient", "D": "stress gradient" }, "correct_answer": "A", "explanation": "The correct answer is A because diffusion is fundamentally driven by the chemical potential gradient, which includes both concentration and other thermodynamic factors. Option B is a common misconception as concentration gradient is only one component of chemical potential. Option C exploits the intuition that temperature affects diffusion but is not the primary driving force. Option D uses a related but incorrect concept from stress-induced diffusion which is a special case.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3404, "question": "What are the commonly used elements in alloy steel?", "answer": "Alloy steel is mainly composed of elements such as Si, Mn, Cr, Ni, Mo, and V, in addition to Fe and C.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求列举合金钢中常用的元素，答案以文字解释和论述的形式给出，没有选项或计算要求。 | 知识层次: 题目考查对合金钢常用元素的基本概念记忆，仅需列举常见元素名称，不涉及复杂分析或应用。 | 难度: 在选择题型中，该题目属于基本定义简答的难度等级。题目仅要求记忆合金钢中常用的元素，正确选项直接列出了这些元素（Si, Mn, Cr, Ni, Mo, V, Fe, C），无需进行概念解释或复杂分析。这种类型的题目主要考察学生对基础概念的简单记忆能力，属于选择题型中最基础的难度层次。", "convertible": true, "correct_option": "Si, Mn, Cr, Ni, Mo, and V, in addition to Fe and C", "choice_question": "Which of the following are commonly used elements in alloy steel?", "conversion_reason": "The answer is a standard list of elements, which can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Si, Mn, Cr, Ni, Mo, and V, in addition to Fe and C", "B": "Al, Cu, Zn, and Pb, in addition to Fe and C", "C": "Ti, W, Co, and Nb, in addition to Fe and C", "D": "All of the above are commonly used in alloy steel" }, "correct_answer": "A", "explanation": "The correct answer is A because Si, Mn, Cr, Ni, Mo, and V are the most commonly used alloying elements in steel for their specific properties like strength, hardness, and corrosion resistance. Option B is incorrect as Al, Cu, Zn, and Pb are not typical alloying elements in steel (they are more common in non-ferrous alloys). Option C is a trap because while Ti, W, Co, and Nb are used in some specialty steels, they are not 'commonly' used like the elements in option A. Option D exploits the AI's tendency to overgeneralize by suggesting all options are correct when they clearly are not.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1510, "question": "A single crystal (BCC) rod is stretched along the rod axis [213] direction to undergo plastic deformation. Given that the slip plane of the single crystal is {110}, determine the final orientation of the test rod (assuming the rod does not fracture before reaching a stable orientation).", "answer": "Let the stable orientation be [u′0w′]. To satisfy n = [000], it is required that [u′0w′] × ([111] ± [1¯11]) = [000], which implies u′ = w′. Therefore, the final stable orientation is [101].", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求通过文字解释和论述来确定单晶棒的最终取向，答案给出了详细的推导过程和结论，属于需要文字解释和论述的简答题类型。 | 知识层次: 题目需要综合运用晶体学知识（BCC结构、滑移面、晶向指数）、塑性变形原理（稳定取向条件）和向量运算（叉积为零条件）进行多步骤推理分析。解题过程涉及对晶体取向变化机理的深入理解，并要求建立数学条件（[u′0w′] × ([111] ± [1¯11]) = [000]）来推导最终稳定取向，属于需要深度分析和综合运用的复杂问题。 | 难度: 在选择题型中，该题目属于最高难度等级。原因如下：", "convertible": true, "correct_option": "[101]", "choice_question": "A single crystal (BCC) rod is stretched along the rod axis [213] direction to undergo plastic deformation. Given that the slip plane of the single crystal is {110}, determine the final orientation of the test rod (assuming the rod does not fracture before reaching a stable orientation).", "conversion_reason": "The answer is a specific orientation [101], which can be presented as a clear option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "[101]", "B": "[111]", "C": "[112]", "D": "[123]" }, "correct_answer": "A", "explanation": "正确答案是A，因为在BCC结构中，拉伸方向最终会稳定在滑移面{110}和滑移方向<111>的对称位置，即[101]。干扰项B利用了常见的直觉错误，认为[111]是BCC的滑移方向；干扰项C设计为数值接近但实际不符合稳定取向；干扰项D保留了原始方向的数值特征但忽略了晶体学稳定条件。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 142, "question": "A borosilicate glass used for sealing lamps has an annealing point of 544°C and a softening point of 780°C. Calculate the activation energy for viscous flow of this glass.", "answer": "According to the formula: η=η0exp(ΔE/RT). At the annealing point of 544°C, η=1.0×10^12 Pa·s, T=544+273=817K; at the softening point of 780°C, η=4.5×10^6 Pa·s, T=780+273=1053K. Solving the simultaneous equations gives: η0=1.39×10^-12 Pa·s, ΔE=373.13 kJ/mol.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求通过给定的温度和粘度数据，应用公式计算玻璃的粘流活化能，解答过程涉及数值计算和公式应用。 | 知识层次: 题目需要应用粘性流动的Arrhenius方程进行多步计算，涉及两个温度点的数据联立求解，需要理解活化能的概念和公式转换，属于中等应用层次。 | 难度: 在选择题中属于中等偏上难度，需要理解粘性流动的激活能计算公式，并能够正确转换温度单位（摄氏到开尔文）。解题过程涉及解联立方程，需要一定的数学能力和对公式的理解。虽然题目提供了关键数据点，但计算步骤较多，容易在单位转换或方程求解中出现错误。", "convertible": true, "correct_option": "373.13 kJ/mol", "choice_question": "A borosilicate glass used for sealing lamps has an annealing point of 544°C and a softening point of 780°C. What is the activation energy for viscous flow of this glass?", "conversion_reason": "The question is a calculation problem with a specific numerical answer, which can be converted into a multiple-choice format by providing the correct answer as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "373.13 kJ/mol", "B": "544.00 kJ/mol", "C": "780.00 kJ/mol", "D": "298.15 kJ/mol" }, "correct_answer": "A", "explanation": "The correct answer is A (373.13 kJ/mol) as it is calculated using the Vogel-Fulcher-Tammann equation for viscous flow activation energy in borosilicate glasses. Option B (544.00 kJ/mol) is a cognitive bias trap using the annealing point temperature directly as the energy value. Option C (780.00 kJ/mol) similarly misuses the softening point temperature. Option D (298.15 kJ/mol) is a professional intuition trap using room temperature (25°C) in kJ/mol, which is a common reference point but irrelevant here.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 917, "question": "Briefly describe normal segregation in the macro-segregation of ingots", "answer": "Normal segregation: refers to the phenomenon where the initially solidified portion has lower solute content and the later solidified portion has higher solute content, according to the alloy's distribution coefficient (assuming k0<1). Due to the large size of the ingot, the composition varies from the surface to the center, resulting in non-uniformity, and the segregation occurs on a macroscopic scale, known as macro-segregation.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 2, "final_level": "Level_3", "reasoning": "题型: 题目要求简要描述正常偏析现象，答案以文字解释和论述的形式呈现，没有涉及选择、判断或计算。 | 知识层次: 题目考查对宏观偏析中正常偏析现象的基本定义和原理的记忆和理解，不涉及复杂计算或综合分析。 | 难度: 在选择题型中，该题目属于中等难度。虽然题目要求的是基础概念记忆，但需要考生理解并描述\"正常偏析\"的定义、形成原因及其在宏观尺度上的表现。这比单纯记忆定义（等级1）要求更高，但不需要进行复杂的概念体系阐述（等级3）。考生需要掌握合金分配系数与凝固顺序的关系，并能解释宏观偏析的形成机制，这属于概念解释和描述的难度层次。", "convertible": true, "correct_option": "Normal segregation: refers to the phenomenon where the initially solidified portion has lower solute content and the later solidified portion has higher solute content, according to the alloy's distribution coefficient (assuming k0<1). Due to the large size of the ingot, the composition varies from the surface to the center, resulting in non-uniformity, and the segregation occurs on a macroscopic scale, known as macro-segregation.", "choice_question": "下列关于正常偏析（normal segregation）在铸锭宏观偏析（macro-segregation）中的描述，正确的是：", "conversion_reason": "简答题的答案是标准术语或概念，可以转换为单选题格式。", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Normal segregation occurs when the initially solidified portion has lower solute content and the later solidified portion has higher solute content, following the alloy's distribution coefficient (k0<1), leading to macroscopic composition variations from surface to center.", "B": "Normal segregation is caused by rapid cooling rates that prevent solute diffusion, resulting in uniform solute distribution throughout the ingot cross-section.", "C": "Normal segregation refers to the preferential segregation of impurities to grain boundaries during solidification, creating microscopic composition variations.", "D": "Normal segregation occurs when the solute content is higher in the initially solidified portion due to inverse distribution coefficient (k0>1), creating a reversed composition gradient." }, "correct_answer": "A", "explanation": "The correct answer A accurately describes normal segregation as the macroscopic composition variation resulting from the alloy's distribution coefficient (k0<1). Option B is incorrect because it describes a scenario that would prevent segregation, not cause it. Option C is a trap that confuses macro-segregation with micro-segregation at grain boundaries. Option D exploits the intuition about inverse distribution coefficients (k0>1) which is irrelevant for normal segregation cases.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 2463, "question": "Estimate the number of clusters containing 10 atoms in 1cm³ of copper at its melting point temperature. The atomic volume of liquid copper is 1.6×10⁻²⁹m³, the surface energy is 0.177J/m², and the melting point is 1356K.", "answer": "According to nᵢ = n exp(-ΔG / k_B T), first calculate the energy ΔG₁₀ of a 10-atom cluster. The radius of the cluster r = (3×10×1.6×10⁻²⁹ / 4π)^(1/3), and the surface area A₁₀ = 4πr² = 4π(3×10×1.6×10⁻²⁹ / 4π)^(2/3). ΔG₁₀ = A₁₀γ = 4π(3×10×1.6×10⁻²⁹ / 4π)^(2/3)×0.177 = 2.52×10⁻¹⁹J. The number of atoms per cm³ n = 1 / (1.6×10⁻²³) = 6.25×10²² cm⁻³. n₁₀ = 6.25×10²² exp(-2.52×10⁻¹⁹ / (1.38×10⁻²³×1356)) = 8.85×10¹⁰ cm⁻³.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_4", "reasoning": "题型: 题目要求进行数值计算和公式应用，包括计算能量、半径、表面积等，并最终得出具体的数值结果。答案中展示了详细的计算步骤和公式应用，符合计算题的特征。 | 知识层次: 题目需要进行多步计算，包括原子团簇半径和表面积的计算、能量计算以及最终的数量估算。虽然涉及公式的直接应用，但需要理解各个参数之间的关系，并进行综合分析。题目还要求对材料科学中的表面能和原子体积等概念有一定的理解，但不需要进行复杂的机理分析或创新设计。 | 难度: 在选择题中属于高难度，题目涉及多步骤的复杂计算和多个物理概念的关联应用。解题过程需要计算原子团簇的半径和表面积，进而求解能量变化，最后应用玻尔兹曼分布公式计算团簇数量。每一步都需要精确的数学运算和对物理概念的深入理解，综合性强，计算复杂度高。", "convertible": true, "correct_option": "8.85×10¹⁰ cm⁻³", "choice_question": "Estimate the number of clusters containing 10 atoms in 1cm³ of copper at its melting point temperature. The atomic volume of liquid copper is 1.6×10⁻²⁹m³, the surface energy is 0.177J/m², and the melting point is 1356K. The number of clusters is:", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as a correct option in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "8.85×10¹⁰ cm⁻³", "B": "1.13×10¹⁴ cm⁻³", "C": "3.72×10⁸ cm⁻³", "D": "5.64×10¹² cm⁻³" }, "correct_answer": "A", "explanation": "正确答案A是通过精确计算表面能平衡和原子体积得出的真实值。干扰项B错误地假设了完全随机分布而忽略了表面能效应；干扰项C错误地使用了固态铜的原子间距；干扰项D混淆了不同温度条件下的原子振动幅度影响。这些干扰项分别利用了：B-忽略关键热力学参数；C-固态/液态概念混淆；D-温度条件错误套用等典型AI易犯错误模式。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 773, "question": "In the cubic crystal system, the possible types of space lattices are F, I, and C", "answer": "×", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目给出一个陈述（立方晶系中可能的空间格子类型是F、I和C），并要求判断其正确性（答案给出×表示错误）。这符合判断题的特征，即判断陈述的对错。 | 知识层次: 题目考查立方晶系中空间点阵类型的基本概念记忆，属于基础概念记忆性知识 | 难度: 在选择题型中，该题目属于基本概念正误判断，仅需记忆立方晶系中可能的空间格子类型即可做出正确判断，无需深入理解或复杂分析。", "convertible": true, "correct_option": "×", "choice_question": "In the cubic crystal system, the possible types of space lattices are F, I, and C", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All amorphous materials will eventually crystallize given sufficient time at temperatures below their glass transition temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "This statement is false because while many amorphous materials can crystallize over time (a process called devitrification), some materials are inherently resistant to crystallization due to their complex atomic structures or kinetic barriers. The use of 'all' makes this an absolute statement that doesn't account for exceptions. Additionally, crystallization typically occurs above (not below) the glass transition temperature where molecular mobility is sufficient for rearrangement.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3119, "question": "What is the main use of controlled expansion alloys?", "answer": "This type of material is used in the electric vacuum industry to seal with glass, ceramics, etc., requiring its expansion coefficient to match that of the sealed material.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释controlled expansion alloys的主要用途，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目考查对控制膨胀合金主要用途的基础概念记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别控制膨胀合金的主要用途，属于基础概念记忆层次。题目直接给出了明确的定义和用途，无需进行复杂的分析或推理，因此难度等级为1。", "convertible": true, "correct_option": "This type of material is used in the electric vacuum industry to seal with glass, ceramics, etc., requiring its expansion coefficient to match that of the sealed material.", "choice_question": "What is the main use of controlled expansion alloys?", "conversion_reason": "The answer is a standard description of the use of controlled expansion alloys, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Sealing in electric vacuum applications where thermal expansion matching is critical", "B": "High-temperature structural components requiring creep resistance", "C": "Biomedical implants needing corrosion resistance and biocompatibility", "D": "Magnetic shielding applications requiring specific permeability characteristics" }, "correct_answer": "A", "explanation": "Correct answer A directly addresses the primary use of controlled expansion alloys in vacuum sealing where thermal expansion matching is essential. Option B exploits the 'high-temperature' intuition but incorrectly focuses on creep resistance. Option C leverages the 'specialty alloy' misconception by suggesting biomedical uses. Option D creates confusion by referencing another specialized property (permeability) that is irrelevant to expansion control.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 6 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 6, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 1586, "question": "The microscopic mechanisms of diffusion in crystalline solids include (11)", "answer": "(11) interstitial mechanism", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求填写一个特定的微观机制名称作为答案，属于需要简短文字回答的类型，而不是从多个选项中选择或判断对错 | 知识层次: 题目考查晶体固体中扩散的微观机制，属于基础概念的记忆和理解，不需要复杂的分析或综合应用。 | 难度: 在选择题型中，该题目仅要求考生记忆并识别晶体固体中扩散的微观机制之一——间隙机制（interstitial mechanism）。这属于基础概念记忆层次，无需解释或分析，只需直接回忆定义或分类即可作答。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "interstitial mechanism", "choice_question": "The microscopic mechanisms of diffusion in crystalline solids include:", "conversion_reason": "The answer is a standard term or concept, which can be converted into a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Interstitial mechanism", "B": "Dislocation climb mechanism", "C": "Grain boundary sliding mechanism", "D": "Surface diffusion mechanism" }, "correct_answer": "A", "explanation": "The correct answer is A because interstitial mechanism is a fundamental microscopic diffusion process in crystalline solids where atoms move through the interstitial spaces. Option B exploits the cognitive bias of associating dislocations with atomic motion, but dislocation climb is not a primary diffusion mechanism. Option C is a high-temperature deformation mechanism, creating a professional intuition trap by confusing diffusion with mechanical behavior. Option D uses a real phenomenon (surface diffusion) but is irrelevant to bulk crystalline diffusion, representing a multi-level verification trap.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 3 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 3, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3773, "question": "A liquid cast iron has a density of 7.65 g/cm3. Immediately after solidification, the density of the solid cast iron is found to be 7.71 g/cm3. Determine the percent volume change that occurs during solidification.", "answer": "the percent volume change during solidification is 0.77%.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用来确定凝固过程中的体积变化百分比，答案是一个具体的数值结果。 | 知识层次: 题目需要进行简单的密度计算和百分比变化计算，属于基本公式的直接应用，不需要多步计算或复杂分析。 | 难度: 在选择题型中，该题目仅需要直接应用密度和体积变化的基本公式进行计算，属于单一公式直接计算的简单题目。解题步骤简单明了，只需套用公式并代入已知数值即可得出答案，无需复杂的分析或多步骤推理。", "convertible": true, "correct_option": "0.77%", "choice_question": "A liquid cast iron has a density of 7.65 g/cm3. Immediately after solidification, the density of the solid cast iron is found to be 7.71 g/cm3. What is the percent volume change that occurs during solidification?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format where the correct option can be clearly identified.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.77%", "B": "0.78%", "C": "-0.77%", "D": "0.83%" }, "correct_answer": "A", "explanation": "The correct answer is A (0.77%) calculated using the formula: % volume change = [(ρ_solid - ρ_liquid)/ρ_solid] × 100. Option B (0.78%) is a close numerical trap exploiting rounding errors. Option C (-0.77%) reverses the sign, exploiting a common calculation direction confusion. Option D (0.83%) mimics typical thermal contraction values, creating a plausible but incorrect material science intuition trap.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 5, "correct_answers": 4, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 5, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4076, "question": "[a] Nickel is majority component (by mass) in certain superalloys such as Waspaloy TM.", "answer": "T", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目是一个陈述句，要求判断其正确性（答案为T/F），符合判断题的特征。 | 知识层次: 题目考查对镍在特定超级合金中作为主要成分的基础知识记忆，属于定义和分类的基本概念层次。 | 难度: 该题目属于基础概念记忆层次，仅需判断关于镍在Waspaloy TM超合金中为主要成分这一事实陈述的正误。在选择题型中，这类直接考察定义或基本事实记忆的题目属于最低难度等级，不需要复杂的理解或分析过程。", "convertible": true, "correct_option": "T", "choice_question": "[a] Nickel is majority component (by mass) in certain superalloys such as Waspaloy TM.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All ceramic materials are inherently brittle at room temperature.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While most ceramics are brittle at room temperature due to their ionic/covalent bonding, certain advanced ceramics like partially stabilized zirconia can exhibit transformation toughening that reduces brittleness. The absolute term 'all' makes this statement false, as material scientists have developed ceramics with improved fracture toughness through microstructural engineering.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 4, "correct_answers": 3, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 4, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3515, "question": "Compare the tensile strength of HT150 and annealed 20 steel", "answer": "The tensile strength of 20 steel is much higher than that of HT150.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求比较两种材料的拉伸强度，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求比较两种材料的拉伸强度，需要理解HT150和20钢的基本性能特点，并能够分析退火处理对20钢性能的影响。这涉及到材料性能的综合分析和概念关联，属于中等应用层次。 | 难度: 在选择题中属于中等难度，需要理解HT150和20 steel的力学性能特点，并进行比较分析。虽然题目涉及多步计算和概念关联，但在选择题型中，正确选项已经提供了明确的结论，减少了推理的复杂性。", "convertible": true, "correct_option": "The tensile strength of 20 steel is much higher than that of HT150.", "choice_question": "Compare the tensile strength of HT150 and annealed 20 steel:", "conversion_reason": "The answer is a clear and definitive statement comparing the tensile strength of two materials, which can be presented as a correct option in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "HT150 has higher tensile strength due to its higher carbon content", "B": "Annealed 20 steel shows superior tensile strength because of its refined grain structure", "C": "Both materials exhibit similar tensile strength after heat treatment", "D": "HT150 demonstrates better tensile strength owing to its cast iron microstructure" }, "correct_answer": "B", "explanation": "Correct answer is B because annealed 20 steel (a low-carbon steel) achieves higher tensile strength through grain refinement during annealing, while HT150 (gray cast iron) has inherent graphite flakes that limit its strength. Option A exploits carbon content misconception (irrelevant for cast iron). Option C creates false equivalence between fundamentally different materials. Option D triggers microstructure bias without considering graphite's weakening effect.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 2, "correct_answers": 1, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 2, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3406, "question": "How is the range of high, medium, and low alloy steels usually divided?", "answer": "High alloy steel: wMe>10%, medium alloy steel: wMe=5%~10%, low alloy steel: wMe<5%.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求解释高、中、低合金钢的范围划分，答案以文字形式给出具体的百分比范围，属于需要简要回答的简答题类型。 | 知识层次: 题目考查对高、中、低合金钢分类标准的记忆和理解，属于基础概念的记忆性知识 | 难度: 在选择题型中，该题目仅涉及基础概念的记忆，即高、中、低合金钢的分类标准。正确选项直接给出了具体的百分比范围，无需复杂的推理或分析。学生只需记住这些数值范围即可正确作答，属于最基本的知识点掌握要求。", "convertible": true, "correct_option": "High alloy steel: wMe>10%, medium alloy steel: wMe=5%~10%, low alloy steel: wMe<5%", "choice_question": "How is the range of high, medium, and low alloy steels usually divided?", "conversion_reason": "The answer is a standard definition that can be presented as a correct option among other plausible but incorrect options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "High alloy steel: wMe>10%, medium alloy steel: wMe=5%~10%, low alloy steel: wMe<5%", "B": "High alloy steel: wMe>15%, medium alloy steel: wMe=8%~15%, low alloy steel: wMe<8%", "C": "High alloy steel: wMe>5%, medium alloy steel: wMe=2%~5%, low alloy steel: wMe<2%", "D": "High alloy steel: wMe>20%, medium alloy steel: wMe=10%~20%, low alloy steel: wMe<10%" }, "correct_answer": "A", "explanation": "The correct answer is A because it follows the standard classification in materials science where high alloy steels contain more than 10% alloying elements (wMe>10%), medium alloy steels have 5-10%, and low alloy steels have less than 5%. Option B uses higher thresholds which might confuse those familiar with stainless steel classifications. Option C reverses the typical ranges, exploiting the cognitive bias of assuming smaller percentages for 'high' classifications. Option D uses exaggerated values that might appeal to those thinking of specialized superalloys rather than standard steel classifications.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 4 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 4, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4287, "question": "Two previously undeformed specimens of the same metal are to be plastically deformed by reducing their cross-sectional areas. One has a circular cross section, and the other is rectangular; during deformation the circular cross section is to remain circular, and the rectangular is to remain as such. Their original and deformed dimensions are as follows:\n\\begin{tabular}{ccc}\n\\hline & Circular (diameter, \\mathbf{m m} ) & Rectangular (\\mathbf{m m}) \\\\\n\\hline Original dimensions & 15.2 & 125 × 175 \\\\\nDeformed dimensions & 11.4 & 75 × 200 \\\\\n\\hline\n\\end{tabular}\nWhich of these specimens will be the hardest after plastic deformation, and why?", "answer": "the hardest specimen will be the deformed circular one with a cold work percentage of 43.8%.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 4, "final_level": "Level_5", "reasoning": "题型: 题目要求解释哪个试样在塑性变形后会最硬，并说明原因。答案需要文字解释和论述，而不是简单的选择或计算。 | 知识层次: 题目需要计算冷加工百分比（多步计算），并理解冷加工对材料硬度的影响（概念关联），但不需要复杂的机理分析或创新设计。 | 难度: 在选择题型中，该题目属于较高难度。首先，题目涉及塑性变形和冷加工百分比的计算，需要学生掌握材料科学中的基本概念和公式。其次，题目要求对圆形和矩形两种不同形状的试样进行计算和比较，增加了复杂性。此外，正确选项需要学生通过多步计算（包括面积计算和冷加工百分比的计算）才能得出，并且需要理解冷加工百分比与材料硬度之间的关系。这种综合分析能力和多步计算的要求使得该题目在选择题型中属于较高难度。", "convertible": true, "correct_option": "the hardest specimen will be the deformed circular one with a cold work percentage of 43.8%", "choice_question": "Two previously undeformed specimens of the same metal are to be plastically deformed by reducing their cross-sectional areas. One has a circular cross section, and the other is rectangular; during deformation the circular cross section is to remain circular, and the rectangular is to remain as such. Their original and deformed dimensions are as follows:\n\n\\begin{tabular}{ccc}\n\\hline & Circular (diameter, \\mathbf{m m} ) & Rectangular (\\mathbf{m m}) \\\\\n\\hline Original dimensions & 15.2 & 125 × 175 \\\\\nDeformed dimensions & 11.4 & 75 × 200 \\\\\n\\hline\n\\end{tabular}\n\nWhich of these specimens will be the hardest after plastic deformation, and why?", "conversion_reason": "The answer is a specific statement that can be directly used as a correct option in a multiple-choice question. The question can be reformatted to present this statement as one of the choices.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "The circular specimen because it undergoes higher cold work (43.8%)", "B": "The rectangular specimen because it experiences greater dimensional change in one direction", "C": "Both will have equal hardness since they are the same material", "D": "The rectangular specimen because its cross-sectional area reduction is larger (48.6%)" }, "correct_answer": "A", "explanation": "The correct answer is A because hardness is directly related to the percentage of cold work, which is calculated based on cross-sectional area reduction. The circular specimen has 43.8% cold work (from 181.5mm² to 102.1mm²) while the rectangular specimen has 31.4% cold work (from 21875mm² to 15000mm²). Option B exploits the intuition that greater dimensional change implies more deformation, but ignores the actual cold work calculation. Option C is a common oversimplification trap. Option D incorrectly calculates area reduction percentage by comparing different dimensions rather than total area.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 4775, "question": "The critical resolved shear stress for copper (Cu) is 0.48 MPa(70 psi). Determine the maximum possible yield strength for a single crystal of Cu pulled in tension.", "answer": "the maximum possible yield strength for a single crystal of Cu pulled in tension is \\sigma_{y} = 0.96 MPa (140 psi).", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过数值计算和公式应用（临界分切应力与取向因子的关系）来确定单晶铜的最大可能屈服强度，答案给出了具体的数值计算结果。 | 知识层次: 题目需要应用临界分切应力的概念和公式进行简单计算，属于基本公式的直接套用和简单计算，不需要多步推理或综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目仅需要应用临界分切应力与屈服强度的基本关系公式（σ_y = 2τ_crss），并进行简单的数值代入和计算。无需复杂的分析或多步骤推理，属于最基础的难度级别。", "convertible": true, "correct_option": "0.96 MPa (140 psi)", "choice_question": "The critical resolved shear stress for copper (Cu) is 0.48 MPa(70 psi). What is the maximum possible yield strength for a single crystal of Cu pulled in tension?", "conversion_reason": "The answer is a specific numerical value, making it suitable for conversion to a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.96 MPa (140 psi)", "B": "0.48 MPa (70 psi)", "C": "1.44 MPa (210 psi)", "D": "0.69 MPa (100 psi)" }, "correct_answer": "A", "explanation": "The correct answer is A (0.96 MPa) because the maximum yield strength occurs when the slip system is oriented at 45° to the tensile axis, requiring twice the critical resolved shear stress. Option B (0.48 MPa) exploits the cognitive bias of directly using the given shear stress value without considering orientation factors. Option C (1.44 MPa) is designed to trap those who incorrectly multiply by 3 instead of 2. Option D (0.69 MPa) uses a plausible-looking intermediate value that resembles √2 times the shear stress, playing on common mathematical intuition errors.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 4570, "question": "Calculate the drift velocity of electrons in germanium at room temperature and when the magnitude of the electric field is 1000 V/m.", "answer": "the drift velocity of electrons in germanium is 380 m/s.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求进行数值计算（计算电子的漂移速度），并给出了具体的电场强度条件。答案是一个具体的数值结果（380 m/s），这表明解答过程需要应用相关公式和计算步骤。 | 知识层次: 题目要求计算电子在锗中的漂移速度，涉及基本公式应用（如漂移速度公式）和简单计算（给定电场强度下的数值计算），属于直接套用公式的简单应用层次。 | 难度: 在选择题型中，该题目仅需要直接应用基本公式计算电子的漂移速度，属于单一公式直接计算的简单应用层次。解题步骤简单，无需复杂的分析或组合多个公式，因此在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "380 m/s", "choice_question": "What is the drift velocity of electrons in germanium at room temperature when the magnitude of the electric field is 1000 V/m?", "conversion_reason": "The answer is a specific numerical value, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "380 m/s", "B": "1900 m/s", "C": "760 m/s", "D": "480 m/s" }, "correct_answer": "A", "explanation": "The correct answer is A (380 m/s) because it matches the known electron mobility in germanium (3800 cm²/V·s) multiplied by the electric field (1000 V/m) with proper unit conversion. Option B (1900 m/s) is a cognitive bias trap, using the hole mobility value instead of electron mobility. Option C (760 m/s) is a unit conversion trap, incorrectly doubling the correct value by failing to convert cm² to m² properly. Option D (480 m/s) is a professional intuition trap, using silicon's electron mobility instead of germanium's.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3470, "question": "Why does alloy steel have better mechanical properties than carbon steel?", "answer": "The addition of alloying elements and appropriate heat treatment can improve or enhance the mechanical properties of steel.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_4", "reasoning": "题型: 题目要求解释合金钢比碳钢具有更好机械性能的原因，答案需要文字解释和论述，而不是选择、判断或计算。 | 知识层次: 题目要求解释合金钢比碳钢具有更好机械性能的原因，涉及合金元素的作用和热处理的影响，需要将多个概念关联起来进行综合分析，但不需要过于复杂的推理或创新应用。 | 难度: 在选择题中属于中等难度，需要理解合金钢和碳钢的基本概念，并综合分析合金元素添加和热处理对机械性能的影响。虽然题目涉及多步概念关联，但在选择题型中通过正确选项可以直接判断，不需要进行深度关联性分析或多角度论述。", "convertible": true, "correct_option": "The addition of alloying elements and appropriate heat treatment can improve or enhance the mechanical properties of steel.", "choice_question": "Why does alloy steel have better mechanical properties than carbon steel?", "conversion_reason": "The answer is a standard explanation that can be used as a correct option in a multiple-choice question. The question can be rephrased to fit a multiple-choice format by providing the correct answer as one of the options and adding plausible distractors.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Alloying elements increase the density of dislocations, enhancing strength through strain hardening", "B": "Alloying elements lower the stacking fault energy, promoting twinning as the dominant deformation mechanism", "C": "Alloying elements reduce the critical resolved shear stress for slip systems", "D": "Alloying elements increase the Burgers vector magnitude of dislocations" }, "correct_answer": "A", "explanation": "Correct answer A is based on the fundamental strengthening mechanism where alloying elements impede dislocation motion. Option B is a cognitive bias trap - while SFE affects deformation mechanisms, it's not the primary reason for improved properties. Option C is a professional intuition trap - alloying actually increases CRSS. Option D is a multi-level verification trap - Burgers vector is an intrinsic property unaffected by alloying.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 2 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 2, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 269, "question": "For spherical Al2O3 particles with a diameter of 1μm surrounded by excess MgO particles, the formation of spinel is observed. At a constant temperature, 20% of the Al2O3 reacts in the first hour. Calculate the time required for complete reaction using the Jander equation.", "answer": "Calculation using the Jander equation: [1-(1-G)^(1/3)]^2 = kt ⇒ k = [1-(1-G)^(1/3)]^2 / t Substituting the reaction time of 1h and reaction progress of 20% given in the problem, we obtain k = [1-(1-0.2)^(1/3)]^2 / 1 = 5.138×10^-3 h^-1 Therefore, the time required for complete reaction (G=1) is t = 1/k = 1/(5.138×10^-3) = 194.62 h", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "medium_application", "knowledge_level_name": "中等应用", "difficulty": 3, "final_level": "Level_3", "reasoning": "题型: 题目要求使用Jander方程进行数值计算，并给出具体的计算步骤和结果，符合计算题的特征。 | 知识层次: 题目需要应用Jander方程进行多步计算，涉及反应动力学和固体反应的基本原理。虽然计算过程相对直接，但需要对公式进行适当变形和数值代入，属于中等难度的应用题目。 | 难度: 在选择题中属于中等偏上难度，需要理解Jander方程的应用并进行多步骤计算。题目要求考生不仅掌握反应动力学的基本概念，还需要能够正确代入数值并解方程。虽然计算过程较为直接，但涉及多个步骤和公式转换，属于综合性计算问题。", "convertible": true, "correct_option": "194.62 h", "choice_question": "For spherical Al2O3 particles with a diameter of 1μm surrounded by excess MgO particles, the formation of spinel is observed. At a constant temperature, 20% of the Al2O3 reacts in the first hour. Using the Jander equation, calculate the time required for complete reaction.", "conversion_reason": "The problem involves a calculation with a definitive numerical answer, making it suitable for conversion to a multiple-choice question format where the correct answer can be presented as one of the options.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "194.62 h", "B": "25.00 h", "C": "5.00 h", "D": "100.00 h" }, "correct_answer": "A", "explanation": "正确答案A基于Jander方程的正确应用：对于球形颗粒的固相反应，反应程度与时间的关系为[1-(1-α)^(1/3)]^2=kt，其中α为反应分数。已知20%反应需1小时，可求出k值，再计算100%反应时间。干扰项B利用线性外推的认知偏差(20%/h→100%/5h)，C是简单倒数计算(1/0.2=5)，D则利用常见时间单位的直觉陷阱。这些干扰项都忽略了固相反应动力学的非线性特征。", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 3816, "question": "Consider a Pb-70% Sn alloy. Determine the composition of the first solid to form during solidification.", "answer": "98% sn", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求通过计算确定Pb-70% Sn合金在凝固过程中首先形成的固体的成分，需要参考相图和相关公式进行计算，答案是一个具体的数值（98% Sn），属于计算题的特征。 | 知识层次: 题目要求根据给定的合金成分（Pb-70% Sn）确定凝固过程中首先形成的固相成分（98% Sn），这需要应用相图的基本知识和简单的相图读取技能。虽然涉及相图的理解，但主要是一个直接的应用过程，不需要多步计算或复杂的综合分析。 | 难度: 在选择题型中，该题目属于单一公式直接计算的难度等级。题目要求确定Pb-70% Sn合金在凝固过程中首先形成的固体的成分，正确选项直接给出了98% Sn。这只需要学生记住或应用相图中关于共晶合金凝固的基本知识，无需复杂计算或多步骤推理。因此，在选择题型内属于最低难度等级。", "convertible": true, "correct_option": "98% sn", "choice_question": "Consider a Pb-70% Sn alloy. What is the composition of the first solid to form during solidification?", "conversion_reason": "The answer is a specific value (98% sn), which can be presented as a correct option in a multiple-choice question format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "98% Sn", "B": "19% Sn", "C": "61.9% Sn", "D": "70% Sn" }, "correct_answer": "A", "explanation": "The correct answer is A (98% Sn) because during solidification of a Pb-70% Sn alloy, the first solid to form will have the composition corresponding to the maximum solubility limit of Sn in Pb at the eutectic temperature (about 98% Sn). Option B (19% Sn) exploits the cognitive bias of confusing the Pb-rich side of the phase diagram with the Sn-rich side. Option C (61.9% Sn) is designed as a professional intuition trap, using the lever rule calculation at room temperature instead of considering solidification behavior. Option D (70% Sn) creates a verification trap by suggesting the overall composition remains unchanged during phase transformation.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 2988, "question": "Using the carburization equation to calculate the value of erf(x/(2√(Dt))), given the surface carbon content ρs=1.2%, initial carbon content ρ0=0.1%, and target carbon content ρ(x,t)=0.45%.", "answer": "erf(x/(2√(Dt))) = (ρs - ρ(x,t))/(ρs - ρ0) = (1.2 - 0.45)/(1.2 - 0.1) = 0.682.", "question_type": "calculation", "question_type_name": "计算题", "knowledge_level": "simple_application", "knowledge_level_name": "简单应用", "difficulty": 2, "final_level": "Level_2", "reasoning": "题型: 题目要求使用给定的公式和数值进行具体计算，最终得出一个数值结果。解答过程涉及数值代入和公式应用，符合计算题的特征。 | 知识层次: 题目主要考查对carburization方程的基本应用，涉及简单的数值计算和公式套用，无需多步计算或复杂分析。 | 难度: 在选择题型中，该题目属于简单公式应用计算难度。虽然需要理解并应用carburization方程中的erf函数关系，但解题步骤较为直接，仅需代入给定的数值进行简单计算即可得出正确选项。不需要复杂的推导或多步骤分析，因此属于等级2难度。", "convertible": true, "correct_option": "0.682", "choice_question": "Using the carburization equation, calculate the value of erf(x/(2√(Dt))) given the surface carbon content ρs=1.2%, initial carbon content ρ0=0.1%, and target carbon content ρ(x,t)=0.45%.", "conversion_reason": "The calculation yields a specific numerical answer, which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "0.682", "B": "0.625", "C": "0.745", "D": "0.550" }, "correct_answer": "A", "explanation": "The correct answer is calculated using the carburization equation: erf(x/(2√(Dt))) = (ρ(x,t) - ρ0)/(ρs - ρ0) = (0.45 - 0.1)/(1.2 - 0.1) = 0.318. Then, erf^-1(0.318) ≈ 0.682. Option B is a common miscalculation error from misapplying the equation. Option C exploits the cognitive bias of overestimating diffusion effects. Option D is designed to trap those who confuse the initial and surface carbon contents.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1396, "question": "Determine whether the following statement is correct: After recovery annealing of cold-deformed metal, its mechanical properties can return to the state before deformation.", "answer": "Incorrect", "question_type": "true_false", "question_type_name": "判断题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_1", "reasoning": "题型: 题目要求判断陈述的对错，答案直接给出了\"Incorrect\"的判断结果，符合判断题的特征 | 知识层次: 题目考查对冷变形金属在恢复退火后机械性能变化的基础概念记忆和理解，属于基本原理的记忆性知识。 | 难度: 该题目属于基础概念正误判断题，仅需记忆金属材料冷变形和再结晶退火后的性能变化这一基本原理即可作答。在选择题型中，这类仅需识别定义或基本原理正确与否的题目属于最低难度等级。", "convertible": true, "correct_option": "Incorrect", "choice_question": "Determine whether the following statement is correct: After recovery annealing of cold-deformed metal, its mechanical properties can return to the state before deformation.", "conversion_reason": "判断题可以转换为正确/错误的单选题格式", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "true_false", "statement": "All cold-worked metals will completely regain their pre-deformation ductility after recrystallization annealing.", "options": [ "True", "False" ], "correct_answer": "False", "explanation": "While recrystallization annealing can significantly restore ductility in cold-worked metals, complete restoration to pre-deformation levels is not guaranteed for all metals. The degree of recovery depends on factors like the metal's purity, annealing conditions, and initial deformation level. Some grain growth or impurity effects may prevent full property restoration. This statement uses an absolute term 'all' which makes it incorrect.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" }, { "idx": 3039, "question": "What type of alloy is YT30?", "answer": "Tungsten-cobalt-titanium alloy", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "basic_concepts", "knowledge_level_name": "基础概念记忆", "difficulty": 1, "final_level": "Level_2", "reasoning": "题型: 题目要求提供具体的合金类型名称，需要文字解释和论述，而不是从选项中选择或判断对错 | 知识层次: 题目考查对YT30合金类型的基本概念记忆，属于基础概念记忆性知识，不需要复杂的分析或应用。 | 难度: 在选择题型中，该题目仅要求记忆YT30合金的基本分类（钨钴钛合金），属于最基础的定义性知识。不需要任何解释或分析步骤，完全符合等级1\"基本定义简答\"的标准。", "convertible": true, "correct_option": "Tungsten-cobalt-titanium alloy", "choice_question": "What type of alloy is YT30?", "conversion_reason": "The answer is a standard term (Tungsten-cobalt-titanium alloy), which can be presented as one of the options in a multiple-choice question.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Tungsten-cobalt-titanium alloy", "B": "Tungsten carbide-cobalt composite", "C": "Titanium carbide-nickel cermet", "D": "Yttria-titanium intermetallic compound" }, "correct_answer": "A", "explanation": "The correct answer is A because YT30 is a tungsten-cobalt-titanium alloy used in cutting tools. Option B is a common misconception due to the prevalence of WC-Co composites in similar applications. Option C exploits the titanium association but incorrectly assumes a cermet structure. Option D creates confusion by introducing yttrium (Y) which is not present in YT30, playing on the 'YT' prefix.", "performance_test": { "model_answered_correctly": false, "sampling_attempt": 1 }, "sampling_summary": { "result_type": "early_stop_incorrect", "total_sampling_attempts": 1, "correct_answers": 0, "incorrect_answers": 1, "is_early_stop": true, "is_all_correct": false, "selected_attempt": 1, "selected_was_correct": false, "difficulty_label": "hard_early_stop" } }, "generation_status": "success" }, { "idx": 1793, "question": "Briefly describe the mechanism of slurry peptization", "answer": "Due to the difference in electrical charges on the edge and face surfaces of plate-like clay particles, face-face, edge-face, or edge-edge associations occur, forming a certain structure in the slurry that increases flow resistance. The peptization process of the slurry involves breaking down this internal structure, transforming edge-face and edge-edge associations into face-face arrangements.", "question_type": "short_answer", "question_type_name": "简答题", "knowledge_level": "complex_analysis", "knowledge_level_name": "复杂分析", "difficulty": 5, "final_level": "Level_5", "reasoning": "题型: 题目要求简要描述泥浆胶溶的机制，答案提供了详细的文字解释和论述，符合简答题的特征。 | 知识层次: 题目要求解释浆体胶溶的机理，涉及对粘土颗粒表面电荷差异的理解，以及不同排列方式对浆体结构的影响。这需要综合运用材料科学知识，进行推理分析和机理解释，属于较高层次的认知能力。 | 难度: 在选择题型中，该题目属于最高难度等级。题目要求考生深入理解粘土颗粒表面电荷差异导致的微观结构变化，并能够解释浆体胶溶过程中结构转变的复杂机理。这需要考生具备综合运用材料科学、胶体化学知识的能力，以及对复杂现象进行全面分析的能力。正确选项涉及多个专业概念（如face-face/edge-face排列）和机理解释，远超选择题常见的简单识别或记忆层面，属于需要深度推理和综合分析的高阶题型。", "convertible": true, "correct_option": "Due to the difference in electrical charges on the edge and face surfaces of plate-like clay particles, face-face, edge-face, or edge-edge associations occur, forming a certain structure in the slurry that increases flow resistance. The peptization process of the slurry involves breaking down this internal structure, transforming edge-face and edge-edge associations into face-face arrangements.", "choice_question": "Which of the following best describes the mechanism of slurry peptization?", "conversion_reason": "The answer is a standard description of a scientific process, which can be presented as a correct option among other plausible but incorrect descriptions in a multiple-choice format.", "perplexity": { "has_perplexity": false, "perplexity_type": null, "perplexity_level": null, "perplexity_reason": null, "missing_info": null }, "generated_options": { "question_type": "multiple_choice", "options": { "A": "Due to the difference in electrical charges on the edge and face surfaces of plate-like clay particles, face-face, edge-face, or edge-edge associations occur, forming a certain structure in the slurry that increases flow resistance. The peptization process of the slurry involves breaking down this internal structure, transforming edge-face and edge-edge associations into face-face arrangements.", "B": "Peptization occurs when the zeta potential of colloidal particles reaches zero, causing complete particle dispersion through neutralization of surface charges by counterions in the solution.", "C": "The process involves mechanical breakdown of particle agglomerates through high shear mixing, where increased kinetic energy overcomes van der Waals forces between particles.", "D": "Peptization is achieved by increasing the slurry viscosity through polymer addition, which creates steric hindrance that prevents particle-particle contact and agglomeration." }, "correct_answer": "A", "explanation": "The correct answer A describes the actual charge-based mechanism of clay particle interactions and structural rearrangement during peptization. Option B is incorrect because zero zeta potential would cause flocculation, not peptization. Option C describes mechanical dispersion rather than the electrochemical peptization process. Option D describes steric stabilization, which is a different mechanism from charge-based peptization. These distractors exploit common misconceptions about colloidal stability mechanisms in material science.", "performance_test": { "model_answered_correctly": true, "sampling_attempt": 5 }, "sampling_summary": { "result_type": "all_samples_correct", "total_sampling_attempts": 6, "correct_answers": 6, "incorrect_answers": 0, "is_early_stop": false, "is_all_correct": true, "selected_attempt": 5, "selected_was_correct": true, "difficulty_label": "easy_all_correct" } }, "generation_status": "success" } ], "sampling_statistics": { "label_distribution": { "hard_early_stop": 1494, "easy_all_correct": 1807, "mixed": 0, "unknown_fallback": 42, "unknown_retry": 0 }, "early_stop_count": 1494, "all_correct_count": 1807, "early_stop_rate": 0.4469039784624589, "all_correct_rate": 0.540532455877954, "total_questions": 3343 }, "api_usage": { "total_generation_calls": 13850, "total_validation_calls": 13850, "total_api_calls": 27700, "average_calls_per_question": 8.285970685013462 }, "generation_metadata": { "generation_timestamp": "2025-06-01 21:47:40", "model_used": "deepseek-chat", "max_sampling_attempts": 6, "success_rate": 1.0 } }